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1
Siddeek, Fathima Zeena. "Water management for lowland rice irrigation." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/71183.
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A procedure was developed to estimate optimum irrigation requirements for lowland rice cultivation in Southeast Asia. The procedure uses a water balance equation of semi-stochastic nature to maintain minimum desired water depths in paddy fields at the end of each irrigation period. The procedure estimates weekly pan evaporation (EV) and rainfall (RF) at different probability levels, which is then used to determine weekly irrigation requirements at different probability levels.
To illustrate the use of the method, the Kalawewa irrigation scheme in Sri Lanka was selected for demonstration purposes. Different transformations were applied to Rf and EV data in an attempt to normalize these variates and to obtain a unique distribution to describe their variations. Statistical analysis of weekly EV arid RF showed that the power transformation was best able to transform the weekly RF and EV data to normality.
Comparison of the use of the model and current system practices showed that a significant amount of water could be saved even when the system was operated at high probability levels (90% reliability). The irrigation water required when the system was operated at the 72% probability level was about 21% less than the amount required when the system was operated at 90% probability level during some weeks.
The EXTRAN flow routing model was used to simulate water flow in the upper reaches of the main canal system for varying discharges at the head gate each day. The simulated water depths were used to determine the gate settings required at the turnout structures to divert the desired amount of irrigation water into the turnout areas.
The flow simulation for the demonstration area, showed that it was not possible to regulate irrigation water from the main reservoir to meet daily demands at all the turnouts. This was due to the large distances between the regulating reservoir and turnouts that caused appreciable time lag for the flow to reach the turnouts farthest from the regulating reservoir.Ph. D.
2
Fall, Thioro. "Soil Management for Improved Rice Production in Casamance, Senegal." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/81457.
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Rice is a staple crop for many countries around the world, and is one of the top three food sources globally. Many environments where rice is grown contain stressors likely to limit its growth and yield. In southern Senegal (Casamance region), rice is mainly cultivated in lowlands near estuaries where drought, salinity, acidity, poor soil fertility, and iron toxicity are the main limiting factors. In Casamance, average rice yield for local farmers is 1 to 2 tons per hectare (809 to 1618 pounds per acre), compared to worldwide average yield of more than 4 tons per hectare. The soil where our 2-year experiment (2014 and 2015) was conducted is highly saline-sodic and acidic, and the salt tolerant cultivar we grew yielded 3.4 tons per hectare in 2013. Our main objective was to increase rice yield. The water table height, salinity, and pH were measured weekly during the rice growing season, and the soil was described, sampled, and analyzed to better understand the water and soil resources. Two planting methods were tested: flat planting and planting on beds. Two soil amendments were compared with each planting method: biochar and crushed oyster shells, alone and in combination. An untreated control was included in the experiment. All plots were fertilized. Treatment effects on soil properties and yield were compared in a split-plot design. Plant tissue was sampled for elemental content. The water table was above the surface and was saline during half of the growing season in 2014, and decreased after rice grain head emerged. Planting methods and amendments did not have an effect on yield in 2014, but biochar amendment increased yield in 2015. In 2014, soil salinity and sodium decreased to below toxic levels late in the growing season in the flat plots but not in the bedded plots. Therefore, flat planting is more appropriate in these lowland rice production systems. Soil pH increased from 4.4 to 7.7 in flat planting where biochar+shell was applied. Soil available nutrients such as P, Mn, and Zn were significantly higher in flat planting compared to beds. Toxic levels of Na (> 2000 milligrams per kilogram) were measured in leaves sampled just before flowering. We recommend flat planting and amending soil with biochar in saline-sodic acid-sulfate paddy soils in Casamance to improve rice yield.Master of Science
3
Åberg, Amanda. "Rice yields under water-saving irrigation management : A meta-analysis." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-146786.
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Water scarcity combined with an increasing world population is creating pressure to develop new methods for producing food using less water. Rice is a staple crop with a very high water demand. This study examined the success in maintaining yields under water-saving irrigation management, including alternate wetting and drying (AWD). A meta-analysis was conducted examining yields under various types of water-saving irrigation compared to control plots kept under continuous flooding. The results indicated that yields can indeed be maintained under AWD as long as the field water level during the dry cycles is not allowed to drop below -15 cm, or the soil water potential is not allowed to drop below -10 kPa. Yields can likewise be maintained using irrigation intervals of 2 days, but the variability increases. Midseason drainage was not found to affect yield, though non-flooded conditions when maintained throughout most of the crop season appeared to be detrimental to yields. Increasingly negative effects on yields were found when increasing the severity of AWD or the length of the drainage periods. Potential benefits and drawbacks of water-saving irrigation management with regards to greenhouse gas emissions, soil quality and nutrient losses were discussed to highlight the complexity of the challenges of saving water in rice production.
4
Genua, Olmedo Ana. "Modelling sea level rise impacts and the management options for rice production: the Ebro Delta as an example." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/461596.
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Les àrees costaneres han de fer front als riscos creixents relacionats amb la PNM. El Delta de l'Ebre és un ecosistema representatiu de la vulnerabilitat de les zones costaneres a la PNM. La producció d’arròs és la principal activitat econòmica, ocupant un 65 % de la superfície total, és sensible a la PNM, i l'augment de la salinitat del sòl, el factor més limitat de la producció. Per tant, cal analitzar els impactes de la PNM, és a dir, la inundació i la salinització del sòl, i desenvolupar les mesures d'adaptació adequades. Vam construir models espacials (1 × 1 m) sobre les zones més vulnerables a la inundació, pèrdua de sediments, salinitat del sòl i pèrdua de producció d'arròs. Mitjançant l’acoblament de dades SIG amb GLMz, i posteriorment, els models es van executar en diferents escenaris previstos per l'IPCC (AR5) fins a l’any 2100. També vam avaluar la viabilitat d'una mesura d'adaptació innovadora basada en la natura, que consisteix a recuperar els sediments atrapats en els embassaments de la conca a la plana deltaica.
L'elevació (inversament) va ser la variable més important a l'hora d'explicar la variació en la salinitat del sòl, els models van predir una disminució de l'índex de producció d'arròs normalitzat (RPI) seguint el gradient d'elevació del delta. Depenent de l'escenari considerat, els models prediuen una reducció del RPI al 2010 del 62.1% al 54,6% per l’any 2100, en l'escenari més conservador (PNM = 0.53 m); i fins al 33.8% per al pitjor dels escenari considerat (PNM = 1.8 m), amb una disminució dels beneficis de fins a 300 € per hectàrea. Per als mateixos escenaris, la superfície d’arrossars inundada va ser del 36-90 %, i la pèrdua de sediment va ser de entre 122 i 418 milions de tones. La mesura d'adaptació proposada, basada en la natura, va tenir un efecte positiu en la producció d'arròs i es pot considerar una opció de gestió innovadora per mantenir els serveis ecosistèmics del Delta de l'Ebre, tot i la PNM. Els nostres models es poden aplicar a altres àrees deltaiques de tot el món, ajudant els agricultors i els ‘stakeholders’ a identificar àrees vulnerables als efectes de la PNM així com a desenvolupar plans de gestió.Las zonas costeras tienen que hacer frente a los crecientes riesgos relacionados con la subida del nivel del mar (SLR). El Delta del Ebro es un valioso ecosistema representativo de la vulnerabilidad de las zonas costeras al SLR. La producción de arroz, la principal actividad económica de la zona, ocupa ca. el 65% de la superficie total, y es sensible a la SLR, y al aumento de la salinidad del suelo el factor más limitante en el cultivo del arroz. Por tanto, es necesario analizar los impactos de la SLR, es decir, la inundaciones y la salinización del suelo, y desarrollar medidas de adaptación apropiadas. Hemos construido modelos espaciales (1 × 1 m) en áreas propensas a inundación, pérdida de sedimentos, salinización del suelo y pérdida de producción de arroz. Se acoplaron datos de GIS con GLMz y los modelos se realizaron bajo diferentes escenarios predichos por el IPCC (AR5) hasta 2100. También evaluamos la viabilidad de una medida innovadora de adaptación basada en la naturaleza que consiste en reintroducir sedimentos atrapados en embalses de bajo Ebro a la llanura deltaica. La elevación (inversamente relacionada a la salinidad del suelo) fue la variable más importante para explicar la salinidad del suelo, por lo que los modelos predijeron una disminución en el Índice de Producción de Arroz normalizado (RPI) siguiendo el gradiente de elevación del delta. Según el escenario considerado, los modelos predicen una reducción de RPI del 62.1 % en 2010 a 54.6 % en 2100 para el escenario más conservador (SLR = 0.53 m); Y al 33,8 % en el peor escenario considerado (SLR = 1,8 m), con una disminución de los beneficios de hasta 300 €/ha. Para los mismos escenarios, la superficie de los campos de arroz inundados osciló entre 36 y 90 %, y la pérdida de sedimentos de 122 a 418 millones de toneladas. La medida de adaptación propuesta tuvo un efecto positivo en la producción de arroz y puede considerarse como una opción de gestión innovadora para mantener los servicios ecosistémicos del Delta del Ebro a pesar del SLR. Nuestros modelos pueden aplicarse a otras áreas deltaicas en todo el mundo, ayudando a los agricultores y a las partes interesadas a identificar áreas vulnerables a los impactos del SLR y a desarrollar planes de manejo.
Coastal areas have to cope with increasing risks related to SLR. The Ebro Delta is a valuable ecosystem representative of the vulnerability of coastal areas to SLR. Rice production is the main economic activity, occupying ca. 65 % of the total surface is sensitive to SLR, and the increase in soil salinity, the most limiting factor. Thus, it is necessary to analyse the impacts of SLR, i.e. flooding and soil salinization, and to develop appropriate adaptation measures. We built spatial models (1 × 1 m) in areas prone to be flooded, sediment loss, soil salinity, and rice production loss. We coupled data from GIS with GLMz and models were run under different scenarios predicted by IPCC (AR5) up to 2100. We also evaluated the feasibility of an innovative nature-based adaptation measure consisting in reintroducing sediments trapped in basin reservoirs into the delta plain. Elevation (inversely related) was the most important variable in explaining soil salinity, thus, models predicted a decrease in normalized Rice Production Index following the delta elevation gradient. Subjected to the scenario considered, the models predict a RPI reduction from 62.1 % in 2010 to 54.6 % by 2100 in the most conservative scenario (SLR = 0.53 m); and to 33.8 % in the worst considered scenario (SLR = 1.8 m), with a decrease of profit up to 300 € per hectare. For the same scenarios, the flooded rice fields’ area ranged 36-90 %, and the sediment loss 122-418 million tonnes. The nature-based adaptation measure proposed had a positive effect on rice production, and it can be considered as an innovative management option for maintaining the Ebro Delta ecosystem services although SLR. Our models can be applied to other deltaic areas worldwide, helping farmers and stakeholders to identify vulnerable areas to SLR impacts and to develop management plans.
5
Joseph, K. D. S. Mervyn. "Physiological and agronomic aspects of rice varietal responses to low and high nitrogen management." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39827.
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Modern rice (Oryza sativa L.) varieties produce very high yields under high input and favorable environments. Limited work has been done to develop plant types suitable for less than optimal environments at moderate N management levels. The objectives of this study were: 1) to examine the relationship between the uptake of N and different leaf characteristics, sink size, and grain yield of three morphologically distinct rice varieties; 2) to examine the CO2 exchange rates (CER) of rice varieties in relation to light, N management, water use efficiencies (WUE), and N use efficiency (NUE): and 3) to determine characteristics of rice varieties that are associated with productive potentials under low N management levels. A greenhouse experiment was conducted in 1989 at Virginia Polytechnic Institute and State University, Blacksburg, VA and a field experiment was conducted in Sri Lanka at two locations in 1990. In the greenhouse experiment three varieties (a traditional, an intermediate, and a modem variety) were grown under four N management (rate and time) treatments: viz 1) a 0 N control, 2) 200 mg N kg⁻¹ of soil split into two applications, 3) 200 mg N kg⁻¹ of soil split into three applications, and 4) 400 mg N kg⁻¹> of soil split into three applications. Competitive use of fertilizer N for the development of either large leaf area or high leaf N content per unit leaf area (LNLA) varied with the rate and timing of N fertilizer application and rice variety. When N supply was limited and early N applications were restricted, the intermediate variety increased LNLA in the flag leaf with little increase in total leaf area of the plant. Specific leaf weight did not differ with N management except for the low value of the N control treatment. Increased N applications reduced stomatal density. Total stomatal number leaf⁻¹ varied little within cultivars indicating that N fertilization enables the leaf to increase leaf area and thereby disperses the fixed number of stomates. Carbon dioxide exchange rates were higher in the flag leaf than lower leaves and were directly correlated to LNLA.Ph. D.
6
Ku, Tsun-Yao. "Educational needs in farm management skills of Taiwan's core rice farmers /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3074418.
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Nguyen, Trung Thanh, Hong Nhat Nguyen, Thi Quynh Anh Nguyen, Phuoc Toan Phan, and Nhat Huy Nguyen. "Emission and management for rice husk ash in An Giang Province." Technische Universität Dresden, 2019. https://tud.qucosa.de/id/qucosa%3A70817.
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An Giang province is one of the largest rice producer regions in Vietnam with 600,000 hectares of paddy field and 4 million tons of rice production every year. The rice milling industry generates a huge amount of rice husk (~23% of paddy rice). The rice husk is currently used as fuel around the province generating rice husk ash (RHA) which causes environmental and health issues. This study focuses on surveying and analyzing the current situation for utilization, management, treatment, and awareness of enterprises and community about generated RHA via a household investigation method. The results showed that, in average, a factory generates 862.4 tons of RHA per year, whereas half of them are reused or are sold for re-utilization in other factories, 56.3% are disposed in the private landfill of the factory, and 1.6 to 6.3 % are directly disposed to nearby rivers or in soil. Most of the interviewed citizens reported that they were aware of the RHA impact on the environment nevertheless, only 2% knew that RHA can be re-utilized for other purposes. Therefore, it is necessary to raise public awareness about the reuse and utilization of RHA to reduce the environmental impact and contribute to the sustainable development of the rice production.Tỉnh An Giang là một trong những vựa lúa lớn nhất Việt Nam, với diện tích khoảng 600.000 ha và sản lượng gần 4 triệu tấn/năm. Cùng với lúa, lượng trấu phát sinh từ quá trình xay xát đang được tái sử dụng làm nhiên liệu đốt cho các quá trình sản xuất khác ở địa phương. Tuy nhiên lượng tro sau quá trình đốt nhiên liệu trấu cũng đang tạo nên một áp lực lên chất lượng môi trường. Do vậy, nghiên cứu này tập trung vào việc khảo sát và phân tích hiện trạng sử dụng, quản lý, xử lý và nhận thức của cơ sở sản xuất hay cộng đồng đối với vấn đề phát thải tro trấu thông qua phương pháp điều tra thực tế. Kết quả cho thấy trung bình mỗi cơ sở phát sinh 862,4 tấn tro trấu/năm với khoảng phân nửa trong số đó được tái sử dụng, 56,3% xử lý bằng cách chôn lấp; 1,6% đến 6,3% xử lý bằng cách đổ bỏ. Hầu hết những người được phỏng vấn biết việc phát thải tro trấu có ảnh hưởng đến chất lượng môi trường, tuy nhiên chỉ có 2% hộ nhận thức được tro trấu có thể tái sử dụng cho các mục đích khác. Điều này cho thấy cần có biện pháp nâng cao nhận thức của cộng đồng đối với việc tái sử dụng tro trấu, nhằm góp phần giảm áp lực của phát thải lên môi trường và đóng góp vào sự phát triển của ngành sản xuất lúa gạo theo định hướng bền vững.
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Smith, Sean P. "Risk Management in the Extractive Industries: Environmental Analysis and Mitigation." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/25490.
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Risk management has been used regularly in the mining industry over the last few decades. The majority of those instances have focused on health and safety issues. Health and safety has improved in the United States, Australia, and other major mining districts because of the successful use of risk management and mitigation practices. Risk management has been used to a lesser extent to reduce or avoid environmental issues as well. There are a number of factors that make utilization of risk management analysis more applicable to health and safety than to environmental issues.
This thesis explores the use of risk management in the context of environmental issues associated with mining. Specifically, two case studies are developed in two self-contained manuscripts: the first focuses on sequestering CO2 while the second focuses on wild rice in Minnesota with regards to the sulfate standard. Through the lens of risk management, an attempt is made to align project goals and efforts with mitigation potential to reduce the likelihood or result of particular risks.
The end result is a reduction in risks due to mitigation. The first manuscript shows how risks disappear over time because they have been categorized and addressed. The project goals are keep on track by eliminating or reducing these risks. The second manuscript can be used by stakeholders to review their potential risks and mitigate those risks if possible/necessary. In contrast to the first manuscript that contains risks that are known and measurable, the second manuscript examines different risks based on four potential outcomes.Master of Science
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Pheng, Sophea. "The potential for exploiting allelopathy to enhance weed management in Cambodian rice farming systems /." [St. Lucia, Qld], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18286.pdf.
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Diallo, Ndeye Helene. "Improved Management of Acid Sulfate Soils for Rice Production in Casamance, Senegal." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/81697.
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Casamance is a region in southern Senegal that traditionally produces rainfed rice, but Senegal produces only 1/3 of its rice consumption. Lowland areas, where rice is primarily produced, have acid sulfate soils with low pH and potential aluminum and iron toxicity. The goal of this work was to determine if soil amendments can alleviate soil acidity, counteract the negative biogeochemical effects that occur in flooded conditions, and increase rice yield. A two-year experiment was conducted to test the following soil treatments – agricultural lime, pulverized oyster shell, biochar, and control (no amendment) – in flat and raised beds. Plots amended with lime and shell materials had increased soil pH, base saturation, Ca, and cation exchange capacity. Meanwhile, biochar elevated particulate organic matter and C:N ratios. Exchangeable Fe and Al were negatively correlated with soil pH, while Geobacteraceae populations (Fe reducing bacteria) increased with pH. A greater proportion of the total Fe was strongly bound in fractions that were less bioavailable in plots amended with shell or lime, and overall rice yields were significantly higher following amendment with shell or lime. During the second growing year these effects diminished, suggesting that liming effects did not persist as expected. These results demonstrate the benefits of soil amendments that raise soil pH and suggest that this effect operates by influencing overall soil nutrient availability to rice plants, but further research is needed regarding the timing and sustainability of the beneficial liming effect.Master of Science
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Ryu, Chanseok. "Analysis of Field Information and Applying Remote Sensing Technology for Rice Management." Kyoto University, 2004. http://hdl.handle.net/2433/147741.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第10891号
農博第1397号
新制||農||889(附属図書館)
学位論文||H16||N3902(農学部図書室)
UT51-2004-G738
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 梅田 幹雄, 教授 笈田 昭, 教授 池田 善郎
学位規則第4条第1項該当
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Jackson, Sydni Blaine. "Adoption and Impacts of IPM for Cambodian Rice Farmers." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/80412.
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This study evaluates the adoption and impacts of Integrated Pest Management (IPM) adoption for rice in Cambodia. Extent of adoption and characteristics of adopters are discovered. Farmers are considered high adopters of IPM if they used two non-pesticide or minimal-pesticide practices to control rice insect, disease, weed, or rodent pests in the last twelve months; farmers are considered low adopters if they used one practice; farmers are considered non-adopters if they used zero practices. IPM practices include pest-resistant variety; stale seedbed (sequential harrowing or harrowing followed by a non-selective herbicide); apply Trichoderma on seeds or seedlings, no insecticide spray for the first 40 days; apply bio-pesticides such as neem, Bt, and metarhizium, and Beauvaria; Sarcocystis bait for rodents; hand weeding at recommended growth stage; and/or another practice specified by the farmer.
Out of 394 farmers surveyed, 40 (10.15%) were found to be high adopters, 228 (57.86%) were found to be low adopters, and 126 (31.97%) were found to be non-adopters of IPM. IPM practices currently include mostly hand-weeding and no spray for 40 days; few other practices were adopted. Our study reveals a need for broader education on rice IPM throughout Cambodia. The high frequency of pesticide applications among rice farmers, the finding that adoption of IPM was not found to have a meaningful influence on the number of pesticide applications, and the finding that less than one-quarter of farmers in our study have received training on IPM reveal the need for increased knowledge of IPM in Cambodia, and the need for future education on IPM to focus on reducing pesticide use.Master of Science
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Chowdhury, Md Tanvir Ahmed. "Arsenic in Bangladeshi soils related to physiographic regions, paddy management and geochemical cycling." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231266.
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It has been established that the impact of arsenic in irrigated agriculture has become a major environmental concern in Bangladesh. However, to date there is still a limited understanding of arsenic in Bangladeshi paddy soils at a landscape level. Besides, there is no data available for soil arsenic on its geographical distribution, geomorphic variations, and biogeochemical relationships across the landscape. In the present study, paddy (n = 1209) and adjacent nonpaddy (n = 235) soil samples across 10 different physiographic regions, comprising the Holocene floodplains and Pleistocene terraces, were collected, and analysed for arsenic and a suite of 16 other elements. The collected paddy soils were from fields irrigated with groundwater (n = 904) and surface waters (n = 281). Additionally, the soils could be categorised into 6 inundation land types. A set of 30 paddy soil samples from 6 physiographic regions were also studied using the diffusive gradients in thin-films (DGT) to assess the porewater dynamics of arsenic, and other geochemical elements in the soils. The paddy soils had generally 60 percent more arsenic than the matching non-paddy soils, perhaps due to the use of arsenic contaminated groundwater for paddy irrigation. Compared to the groundwater irrigated paddy soils, the surface water irrigated paddy soils had lower arsenic concentrations, but higher concentrations of most of the other elements. Within the topologically different inundation land types, the concentrations of arsenic and other elements, including the toxic metals, were found to be elevated in more deeply and prolonged flooded low-lying soils. The soils in the different physiographic regions had variability in arsenic concentrations as well as in their indigenous biogeochemical characteristics. The inherent concentrations and variability in arsenic and most other elements, including nutrients, were greater in the Holocene floodplain soils compared to the Pleistocene terrace soils. Paddy soils in Bangladesh have a high potential for arsenic resupply from soil solid phase to soil solution phase. In the physiographically different soils across the landscape, there is less difference in nutrient/ toxin bioavailability in the paddy soils than might be predicted based solely on the total concentrations in the soils. Therefore, distinctions of soils based just on total concentrations are perhaps misleading, particularly, when elements mobility under reducing paddy environment is concerned. While the bioavailable/ phytoavailable fractions of the elements in soils are of major concern with respect to the uptake by the growing plants, it is of utmost importance to consider the labile concentrations of elements in soil solution rather than the soil total concentrations. The present study substantiates that arsenic is simply associated with less well weathered/ leached soils and sediments, suggesting that it was either due to the geological newness of Holocene sediments or differences between the sources of sediments that gave rise to the arsenic problems in soils of Bangladesh. The inherent biogeochemical variability along with the complexity of the nature and properties of the soils at local and regional levels across the landscape of the dynamic sedimentary depositional environment in Bangladesh should be considered, in any future research on arsenic in the soil-water-crop systems in Bangladesh environment.
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Avila, Luis Antonio de. "Imazethapyr: red rice control and resistance, and environmental fate." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2511.
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Imazethapyr was recently approved for use in rice, but limited information is available
regarding its efficacy, environmental fate or potential red rice resistance. Therefore,
experiments were conducted to 1) determine the effect of flooding time, and stage of
imazethapyr application in red rice control, 2) assess the acetolactate synthase resistance
to imazethapyr on red rice ecotypes, 3) determine the relative photolysis of imazethapyr,
and 4) determine the effect of soil and moisture on imazethapyr adsorption and
availability.
When imazethapyr was applied in sequential application of PRE followed by a POST
application, to achieve >95% red rice control, flood needed to be established within 14
DAT when imazethapyr was applied EPOST, and 7 DAT when imazethapyr was applied
LPOST. Delaying the flood up to 21 DAT reduced rice grain yield for both EPOST and
LPOST application timings.
Based on enzymatic activity, the mean I50 values were 1.5, 1.1, 1.5, 1.6, 20.8, and
590.6 mM of imazethapyr, respectively, for LA 5, MS 5, TX 4, ??Cypress??, ??CL-121??, and
??CL-161??. CL-161 was 32 times more resistant than CL-121, and at least 420 times
more resistant than the average of the red rice ecotypes and ??Cypress??. Results from the
ALS assay showed that red rice ecotypes and Cypress had high susceptibility to
imazethapyr when compared with the tolerant CL-121 and the resistant CL-161.
Measurable enzymatic tolerance to ALS-inhibiting herbicides has not yet developed in
these red rice ecotypes. Imazethapyr quantum yield (fI ) was 0.023 ?? 0.002 while the hydroxyl radical rate
constant ( I
OH k?? ) was 2.8 ?? 0.44 x 1013 M-1 h-1. These results show that imazethapyr is
susceptible to both direct and indirect photolysis. The results also show that
imazethapyr photolysis in paddy water will be affected by turbidity due to its impact on
the availability of sunlight to drive direct and indirect photolysis reactions.
Imazethapyr was more available and more concentrated in sandy soil. With higher
amounts of water in soil there was greater amount of imazethapyr in soil solution and a
lower concentration of herbicide due to dilution. The double centrifuge method
provided a better estimate of plant available herbicide.
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Adams, Charles Andrew. "Impact of water management and agronomic practices on the performance of insecticide seed treatments against rice water weevil, Lissorhoptrus oryzophilus Kuschel, in Mississippi rice." Thesis, Mississippi State University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1536056.
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Two field trials were conducted to determine the impact of water management on the efficacy of insecticide seed treatments against rice water weevil, Lissorhoptrus oryzophilus Kuschel, in rice at the Delta Research and Extension Center during 2011 and 2012. The performance of thiamethoxam, chlorantraniliprole, and clothianidin was evaluated when the permanent flood was established at different timings (6 and 8 weeks after planting) and the effect of flush number (0, 1, or 2) on seed treatment performance was evaluated. Seed treatment efficacy was not impacted by delayed flooding, but 2 flushes reduced efficacy of some seed treatments.
Experiments were also conducted to determine the impact of reduced seeding rates found in hybrid rice production on the efficacy of insecticide seed treatments targeting rice water weevil. Efficacy was similar when comparing currently labeled rates of thiamethoxam, chlorantraniliprole, and clothianidin with higher rates of these products.
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Sam-Amoah, Livingstone Kobina. "Assessment of potential and actual performance of rice production systems in Ghana." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341773.
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Nanson, Weldon Duane. "Red rice (Oryza sativa L.) ecotype tolerance to herbicides and winter weed management practices." Thesis, [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1411.
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Halid, Hariyadi. "Interactions between stored products insects in relation to their management in Indonesian milled rice." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47097.
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Sutton, Claire L. "Impact of Management on Soil Fertility and Rice Yields in Smallholder Farms in Tanzania." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1431003210.
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Yu, Lesley (Lesley Tak Yan). "Waste to wealth : an economic analysis of applications for Rice Husk Ash in India." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/107587.
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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, Engineering and Management Program, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 87-[90]).
As the world's second largest rice grower, India can generate up to 5 million MT of ash from burning rice husk for fuel. The material that remains after combustion, known as Rice Husk Ash (RHA), is high in silica content, provides good insulation, and has a large surface areas for chemical reactions. These characteristics of RHA allow it to be used in a variety of applications such as insulation in steelmaking, substitute for raw material in the cement and brickmaking industry, water filtration, pest control, and the production of precipitated silica. While RHA is currently used in the steel industry in India, and to a smaller degree, in the cement industry, there are many waste-to-wealth opportunities to use RHA which are currently not being leveraged. This results in a loss of land for RHA disposal and more importantly, wasted opportunities to extract value from RHA. There has been a large amount of research conducted on using RHA. The publications around this research have typically been broad and qualitative, describing the potential applications of RHA on a high level, or focused on technical details pertaining to a specific set up using RHA. While the information currently available is extremely important, it is not easily leveraged by entrepreneurs who would be interested in increasing their use of RHA. There seems to be a lack of studies which compare the various applications for RHA qualitatively. The purpose of this thesis is to help current and potential RHA entrepreneurs to apply available research in making decisions about how to make use of RHA, by creating a framework to assess the applications of RHA economically. While this paper is focused on RHA, it is intended that the framework can be used in assessing opportunities to use other biomass ash material.
by Lesley Yu.
S.M. in Engineering and Management
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Atwill, Richard Lee II. "Evaluation of water and nitrogen management practices in southern US rice (Oryza sativa L.) production." Thesis, Mississippi State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1586943.
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Nitrogen (N) fertility and irrigation costs are the greatest input expenses required for rice production in Mississippi, therefore N management and irrigation should be conducted in efficiently. Field experiments were conducted at the Delta Research and Extension Center in Stoneville, MS, and the LSU AgCenter in Crowley, LA, to evaluate water and nitrogen management practices. Nitrogen use efficiency and yield were not different for alternate wetting and drying (AWD) systems compared to a traditional continuous flood. Additionally, experiments were conducted to test for differences comparing two experimental designs, randomized complete block (RCB) and split-plot (SP), for N-rate response trials in Mississippi. Rice grain yield response to N-rate was similar for RCB and SP designs, therefore either experimental design would be appropriate for N-response experiments in rice. Increasing efficiency of water and N management practices further improves environmental and economic benefits from rice production in Mississippi.
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Janz, Baldur [Verfasser], Ralf [Akademischer Betreuer] Kiese, and Heinz [Akademischer Betreuer] Rennenberg. "Greenhouse gas footprint of organic amendments and water management in rice cropping systems in Southeast Asia." Freiburg : Universität, 2019. http://d-nb.info/1209052229/34.
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Tariq, Azeem. "Development and adaptation of water management systems to mitigate greenhouse gas emissions from intensive rice production." Thesis, Montpellier, SupAgro, 2018. http://www.theses.fr/2018NSAM0021.
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Pour répondre à la demande de la population croissante, la production de riz doit être augmentée de 40% d’ici 2030. Cependant cette production émet des gaz à effet serre (GES), tel que le méthane (CH4), qui contribue au réchauffement climatique. Les stratégies de gestion, telles que le drainage des sols et la gestion durable des résidus, sont essentielles pour diminuer les émissions de GES des rizières, mais cela entrent souvent en conflit avec les pratiques de gestion des riziculteurs. L'objectif de ce projet était d'étudier le potentiel d'atténuation des GES par des pratiques de drainage et de gestion des résidus et par l’identification des opportunités et les contraintes auxquelles sont confrontés les petits exploitants dans la mise en œuvre des pratiques. Le projet a été élaboré en utilisant une approche interdisciplinaire incluant mésocosme en chambre climatique, des campagnes sur le terrain et une enquête après des agriculteurs au Vietnam. La première étude sur le mésocosme a été menée pour identifier l'impact du drainage en début et mi-saison sur les émissions de CH4 et de N2O par des sols amendés avec des résidus frais et compostés à différents niveaux de sol C (article I). La deuxième étude sur le mésocosme incluait des résidus de riz enrichis en 13C pour comprendre l'effet de la pré-plantation, d’un drainage précoce et à mi-saison sur la contribution des résidus C aux émissions de CH4 (article III). Des expériences de terrain ont été menées pendant deux saisons (printemps et été) pour documenter l'effet de la pré-plantation, du drainage en début et à mi-saison sur les émissions de CH4 et de N2O par des sols modifiés par l’apport de résidus dans deux systèmes de gestion d’eau: un système efficace de gestion de l'eau et un système de contrôle d'eau conventionnel (article II). Trente-cinq petits producteurs de riz ont été interviewés pour évaluer la diversité des pratiques de gestion des terres dans la région et comprendre leurs pratiques de culture, leurs défis et leurs contraintes à l'échelle de la rizière. Quatre ateliers ont été menés avec des agriculteurs, des conseillers agricoles locaux et régionaux pour concevoir et évaluer les pratiques de production de riz adaptées au climat, basées sur la gestion de l'eau et des résidus (article IV). Les études de laboratoire et de terrain ont montré que les pratiques de drainage (pré-plantation et drainage précoce) pouvaient atténuer les émissions de GES sans compromettre le rendement du riz. Au laboratoire, le drainage avant plantation a considérablement réduit les émissions de CH4 de 70 à 80%, alors que sur le terrain, le drainage se montre moins efficace dans la réduction des émissions de CH4 en raison des activités opérées par les agriculteurs avant transplantion. Dans l’étude de terrain, le drainage précoce et en mi-saison a diminué les émissions de CH4 de 67% et 43% dans les systèmes comprenant une gestion de l’eau efficaces et inefficaces. Au laboratoire, l’addition d’un drainage en début et mi-saison a réduit les émissions de CH4 de 75 à 90%. Sur le terrain, le système efficace de contrôle de l'eau associé avec une bonne aération des sols a considérablement augmenté le potentiel de diminution du CH4 des sols drainés et modifiés par les résidus. L'étude isotopique a indiqué que l'aération des sols au stade précoce (pré-plantation ou début de saison) réduit les émissions de CH4 dérivés des résidus de 57 à 87%. Cependant, les résultats ont mis en évidence que l’amélioration des pratiques de drainage impactaient très peu les émissions de N2O. Les résultats de l'étude participative ont souligné l'importance d'impliquer les agriculteurs et les acteurs locaux dans la conception des systèmes d'atténuation des GES. Ces résultats ont mis en évidence les contraintes et les opportunités possibles pour la mise en œuvre réussie des stratégies d'atténuation des GES dans les rizières des petits exploitantsRice production needs to increase by 40% to meet the demand of the world’s growing population by 2030, yet rice production contribute to global warming with elevated GHG emissions, particularly of methane (CH4). Management strategies, such as drainage of paddy soils & sustainable residue management are essential in order to mitigate GHG emission from rice systems, but they often conflict with the practical management preferences of rice farmers. The objective of this project was to investigate the GHG mitigation potential of drainage practices and residue management techniques, and to identify the constraints and opportunities faced by smallholders in the implementation of mitigation practices under local conditions. The project was formulated using an interdisciplinary approach that included two mesocosm studies in growth chamber, two field campaigns and a field survey of farmers in Vietnam. First mesocosm study was conducted to verify the impact of early season drainage and midseason drainage on CH4 and N2O emissions from fresh and composted residue-amended soils at different soil C levels (Paper I). Then second mesocosm study was conducted using 13C-enriched rice residue to understand the effect of pre-planting, early-season and midseason drainage on the residue carbon contribution to CH4 emissions (Paper III). Field experiments based on farmers’ field conditions were conducted for two seasons (spring and summer) to document the effect of pre-planting, early-season and midseason drainage on CH4 and N2O emissions from residue-amended soils under two field water management systems: an efficient field water control system and a conventional, inefficient field water control system (Paper II). Thirty-five smallholder rice farmers were interviewed to capture the diversity of different land management practices in the area and understand their cropping practices, challenges and constraints faced at field scale. Four workshops were conducted with farmers, local agricultural advisors and regional stakeholders to design and assess the climate-smart rice production practices, based on water and residue management (Paper IV). The lab and field studies showed that drainage practices (pre-planting and early season drainage) had the potential to mitigate GHG emissions without compromising rice yield. Pre-planting drainage greatly reduced CH4 emissions in the lab experiment by 70-80%, while in field condition pre-planting drainage had less effect on CH4 emission reduction due to constraints with farmers’ field operations before transplanting. Early season drainage reduced CH4 emissions in both lab and field experiments. In field study, early plus midseason drainage lowered the CH4 emissions by 67% and 43% in the efficient and inefficient field water management systems respectively. In lab, early plus midseason drainage lowered CH4 emissions by 75-90 %. The efficient field water control system and good soil aeration significantly increased the CH4 mitigation potential of the drainage regimes from residue-amended soils. The isotopic study in lab indicated that soil aeration in the early stage (pre-planting or early season) reduced the residue-derived CH4 emissions by 57-87%. The results highlighted that the effects of improved drainage practices on N2O emissions were very low when considering the total GHG effects of CH4 and N2O. The results of the participatory study highlighted the importance of involving farmers and local stakeholders in the process of designing the mitigating systems. The active involvement of farmers and local stakeholders in the process of designing, testing and assessing the water management systems highlighted the constraints and feasible options for successful implementation of GHG mitigation strategies in smallholders’ rice fields
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Kwesiga, Julius [Verfasser]. "Assessing and targeting management options for smallholder rice-based systems in Kilombero floodplain, Tanzania / Julius Kwesiga." Bonn : Universitäts- und Landesbibliothek Bonn, 2021. http://d-nb.info/1235525007/34.
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Subasubani, Joseph Kamwi. "An evaluation of the green scheme programme : a case of the Kalimbeza rice project." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95985.
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Thesis (MPA)--Stellenbosch University, 2014.ENGLISH ABSTRACT: Approximately three out of four people in developing countries such as Namibia live in rural areas. The majority of these rural poor’s livelihoods depend directly or indirectly on agriculture. Therefore, there is an urgent need to design agricultural programmes that focus on rural communities in order to reduce incidences of poverty. Although the Namibian Government invests in the agricultural sector, hunger for both humans and animals were evident in 2012. The starvation situation was worsened by high food prices, compounded with a high unemployment rate that meant the majority of the population could not afford to pay for food. Evidence shows that Namibia is a net food importer; meaning that less local food production is taking place. Therefore, the government is trying to reverse the situation of relying on imported food, by enhancing local production, and one of the ways of achieving this goal is through the Green Scheme Programme. The research problem of this study is defined as follows: “An evaluation of the Green Scheme Programme: A case of the Kalimbeza Rice Project”. The study commences by exploring the literature on the role of the state in improving the socioeconomic status of its citizens. Many developing countries have weak private sectors; therefore, governments remain with the responsibility to spearhead development. With unrestrained unemployment, poverty and inequality, state-led development is the solution in uplifting the socio-economic status of people, especially the rural poor. Since the rural poor depend on agriculture for their livelihoods, it is necessary for Government to devise Sustainable Livelihood programmes in the sector, which many people rely upon for survival. Reducing incidences of rural poverty calls for Sustainable Livelihood programmes that the Namibian Government came up with, such as the approximately N$ 1.2 billion per annum Green Scheme Programme. This is an irrigation programme that aims at increasing agricultural production, contribute to the Gross Domestic Product, promote food security, create jobs and promote skills development. The study sought to establish whether the Green Scheme Programme is effective in achieving its intended, and at times, unintended goals. The Kalimbeza Rice Project, under the Green Scheme Programme was chosen as a case study. Evidence from the study shows that employment creation took place, because many locals have secured temporary jobs at the farm, and the salaries earned have had a positive impacts on their lives. Food security has not been fully achieved, as only about 25 per cent of the total farm area is cultivated yearly. Finally, the study suggests that there is an urgent need for the Green Scheme Programme and all its projects to speed operations in order to achieve the country’s Vision 2030.
AFRIKAANSE OPSOMMING: Ongeveer drie uit elke vier mense in ʼn ontwikkelende land soos Namibië is woonagtig in landelike gebiede. Die meerderheid van landelike armes se inkomste is direk of indirek afhanklik van lanbou aktiwiteite. Dus, is daar ʼn dringende behoefte aan lanbou ontwikkelingsprogramme wat spesifiek fokus op landelike gemeenskappe om sodoende die voorkoms van armoede te verminder. Alhoewel die Namibiese regering belê in die lanbousektor, was lae vlakke van voedselsekuriteit vir beide mens en dier nogsteeds sigbaar in 2012. Die kroniese hongerte situasie in Namibië word grotendeels verger deur hoë voedselpryse. ʼn Hoë werkloosheidsyfer dra ook daartoe by dat die meerderheid armes nie voedsel kan bekostig nie. Navorsing toon dat Namibië ʼn netto invoerder is van kos. Dit beteken dat Namibië minder plaaslik voedsel produseer. Gevolglik, probeer die Namibiese regering die afhanklikheid op ingevoerde voedsel verminder deur die verbetering van plaaslike produksie vermoëns. Een van die maniere wat hulle gebruik om dit te bewerkstellig is deur die regering se Green Scheme Program. Die navorsingsprobleem van dié studie word as volg gedefinieer: ʼn Evaluering van die Green Scheme Program: Die Kalimbeza Rice Project as gevallestudie. Die vertrekpunt van dié studie begin deur die verkenning van literatuur wat spesifiek handel oor die rol van die staat in die verbetering van die sosio-ekonomiese status van sy burgers. Baie ontwikkelende lande het swak of klein privaat sektore, dus bly regerings verantwoordelik om ontwikkeling moontlik te maak. Ongebreidelde werkloosheid, armoede en ongelykheid noodsaak staat geleide ontwikkeling as die enigste oplossing vir die opheffing van die sosio-ekonomiese status van mense, veral landelike armes. Die feit dat landelike armes grotendeels afhanklik is van landbou vir inkomstes en oorlewing, is dit nodig vir die regering om ʼn Volhoubare Lewensbestaan Program te ontwikkel in die sektor, waarop baie mense aangewese is vir oorlewing. Die vermindering van voorvalle van landelike armoede kan toegeskryf word aan die Volhoubare Lewensbestaan Program wat deur die Namibiese regering geïmplementeer word, soos die ongeveer N$ 1.2 biljoen per jaar Green Scheme Program. Dit is ʼn besproeiingstelsel program wat verhoogde lanbouproduksie ten doel het, as ook bydra tot die Bruto Binnelandse Produk, bevordering van voedselsekuriteit, werkskepping en die bevordering van vaardigheidsontwikkeling. Dié studie sal poog om vas te stel of die Green Scheme Program effektief is in die bereiking van beoogde doelwitte, en by tye, die bereiking van onvoorsiene doelwitte. Die Kalimbeza Rice Project, as deel van die Green Scheme Program, sal dien as n gevallestudie. Getuienis van die studie toon dat werkskepping wel plaasgevind het, omdat baie plaaslike inwoners tydelik in diens geneem is op die plaas, en die salarisse ontvang het alreeds ʼn positiewe effek gehad op hul lewens. Voedsel sekuriteit is nog nie ten volle verwesenlik nie, omdat slegs 25% van die totale plaas oppervlakte onder verbouing is. Gevolglik, dui die studie daarop dat daar ʼn onmiddelike behoefte bestaan vir die Green Scheme Program en al sy onderskeie projekte om sodoende pogings te versnel in die bereiking van die land se Visie 2030.
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Schmidt, Anja [Verfasser], and Roland [Akademischer Betreuer] Brandl. "Decomposition driven by invertebrates in tropical rice ecosystems: impacts of management strategies / Anja Schmidt. Betreuer: Roland Brandl." Marburg : Philipps-Universität Marburg, 2015. http://d-nb.info/1079001514/34.
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Thinlay. "Rice blast, caused by Magnaporthe grisea, in Buthan and development of strategies for resistance breeding and management /." Zürich, 1998. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12777.
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Pandey, Surya Prasad. "Opportunities for soil organic matter and nutrient management in the rice-wheat system of the Nepal Terai." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275943.
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Ngo, Thi Thanh Truc, Vu Khanh Ho, Sy Nam Tran, Van Chin Duong, Van Cong Nguyen, and Van Hung Nguyen. "Quantification of direct and indirect greenhouse gas emissions from rice field cultivation with different rice straw management practices – A study in the autumn - winter season in An Giang Province, Vietnam." Technische Universität Dresden, 2018. https://tud.qucosa.de/id/qucosa%3A33320.
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This study resulted in a comparative analysis of greenhouse gas emissions (GHGE) for rice production with different infield rice straw management practices based on an experiment conducted in An Giang Province of Vietnam, during the autumn - winter season of 2016. Direct field GHGE was analyzed based on in-situ measurement and the total direct and indirect GHGE were estimated by applying the life cycle assessment using Ecoinvent3 database which is incorporated in SIMAPRO software. The experiment was conducted based on a completely random design with three treatments and three replications. The three treatments are [T1] Incorporation of straw and stubbles treated with Trichoderma; [T2] Incorporation of stubbles and removal of straw; and [T3] In-field burning straw. Closed chamber protocol and gas chromatography (SRI 8610C) was used to measure and analyse CH4 and N2O. CH4 emission rate was not significantly different (p>0.05) among the three treatments during sampling dates except on the days 17 and 24 after sowing (DAS). N2O emission rate was not significantly different (p>0.05) either. However, there were high variations of N2O emission after the dates of urea applied. Direct field emissions of CH4, N2O and CO2 equivalent (CO2eq) are not significantly different among the three treatments, but the amount of CO2eq per kg straw in T1 of incorporating rice straw treated with Trichoderma is significantly higher than in T3 of in-field burning straw. LCA based analysis resulted in total GHGE in the range of 1.93-2.46 kg CO2-eq kg-1 paddy produced consisting of 53-66% from direct soil emissions. Incorporationof straw treated with Trichoderma did not indicate the improvement of paddy yield. However, the organic matter, N-NH4+, and N-NO3- of this treatment was higher than those of the other researched treatments. This research was just conducted in one crop season, however, the results have initial implications for the other crop seasons.Nghiên cứu này phân tích phát thải khí nhà kính từ sản xuất lúa theo các biện pháp quản lý rơm rạ khác nhau dựa vào thí nghiệm được thực hiện ở vụ Thu Đông năm 2016 tại tỉnh An Giang, Việt Nam. Lượng phát thải khí nhà kính từ đất đã được phân tích dựa vào kết quả đo đạt tại ruộng và tổng lượng phát thải khí nhà kính trực tiếp và gián tiếp được ước tính bằng phương pháp vòng đời sử dụng cơ sở dữ liệu Ecoinvent3 gắn kết với phần mềm SIMAPRO. Thí nghiệm được bố trí hoàn toàn ngẫu nhiên gồm 3 nghiệm thức và 3 lần lặp lại. Các nghiệm thức gồm [T1] vùi rơm và rạ với Trichoderma, [T2] lấy rơm ra khỏi ruộng và vùi rạ và [T3] đốt rơm. Kỹ thuật buồng kín (closed chamber protocol) và máy sắc ký khí (SRI8610C) được sử dụng để đo đạt và phân tích khí CH4 và N2O. Tốc độ phát thải khí CH4 không khác biệt giữa ba nghiệm thức, ngoại trừ kết quả ở lần lấy mẫu 17 và 24 ngày sau sạ. Tốc độ phát thải N2O cũng không có sự khác biệt giữa các nghiệm thức. Tuy nhiên, tốc độ phát thải biến động rất lớn sau các ngày bón phân đạm. Lượng phát thải trực tiếp từ ruộng của CH4, N2O và CO2 tương đương (CO2-eq) không có sự khác biệt giữa ba nghiệm thức, nhưng lượng CO2-eq/kg rơm ở nghiệm thức vùi rơm và rạ với Trichoderma (T1) cao hơn nghiệm thức đốt rơm (T3). Kết quả phân tích LCA cho thấy lượng phát thải khí nhà kính dao động trong khoảng 1,93 – 2,46 kg CO2-eq/kg lúa với 53 – 66% lượng phát thải trực tiếp từ trong đất. Vùi rơm rạ với Trichoderma chưa cải thiện được năng suất lúa. Tuy nhiên, phần trăm chất hữu cơ và hàm lượng đạm hữu dụng trong đất của nghiệm thức này cao hơn so với hai nghiệm thức còn lại của thí nghiệm. Nghiên cứu này chỉ mới được thực hiện một vụ, nhưng đã mang lại nhiều kết quả có thể ứng dụng cho các vụ sau.
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Dang, Phuong M. "Optimal Management of Renewable Resources: A Dynamic Model of Surface Water Contamination From Pesticide Use in Rice Production in the Mekong Delta, Vietnam." Thesis, University of Hawaii at Manoa, 2002. http://proquest.umi.com/pqdweb?index=0&did=765044371&SrchMode=1&sid=2&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1209140340&clientId=23440.
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Nguyen, Trung Dung. "Review of postharvest rice straw use: change in use and the need for sustainable management policies in Vietnam." Technische Universität Dresden, 2019. https://tud.qucosa.de/id/qucosa%3A70831.
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Annually, about 40-60 million tons of postharvest straw are generated in Vietnam. Although considered as renewable resources and economic goods, straw is still burned in the field because there is no longer needed for cooking, roofing and fodder as before 1990s. The general economic development of the country and the rural area changed all the previous practices of using straw. This paper analyzes the socio-economic and technical causes of this phenomenon and summarizes the economic and environmentally friendly uses of rice straw in the future. In addition, it points out that policy failures in the management of straw currently exist and that policies for integrated straw management are needed to improve the value chain in the supply and consumption of straw products; to enhance the effectively use of this resource and minimize environmental pollution.Hàng năm phát sinh khoảng 40-60 triệu tấn rơm sau thu hoạch ở Việt Nam. Mặc dù được coi là tài nguyên tái tạo và hàng hóa kinh tế, song rơm vẫn bị đốt bỏ ở ngoài ruộng do không còn nhu cầu nhiều cho đun nấu, lợp mái nhà và chăn nuôi như trước những năm 1990. Tình hình phát triển kinh tế chung của đất nước và khu vực nông thôn đã làm thay đổi tất cả thói quen dùng rơm rạ trước đây. Bài báo này phân tích một cảnh tổng quan những nguyên nhân kinh tế - xã hội và kỹ thuật dẫn đến hiện tượng này, tổng hợp những khả năng sử dụng kinh tế và thân thiện môi trường của rơm rạ trong tương lai. Ngoài ra chỉ ra những thất bại về chính sách trong quản lý rơm rạ hiện nay và cần có các chính sách quản lý tổng hợp rơm rạ để nâng cao chuỗi giá trị trong cung ứng và tiêu thụ các sản phẩm rơm rạ, tăng cường việc sử dụng có hiệu quả tài nguyên này và giảm thiểu ô nhiễm môi trường.
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Fox, Karyn M. "Resilience in Action: Adaptive Governance for Subaks, Rice Terraces, and Water Temples in Bali, Indonesia." Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/242455.
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Although there is a growing literature on resilience and collaborative approaches to ecosystem management, there are relatively few empirical case studies on the process of adaptive governance. Moreover, previous research offers limited insights into the conditions that facilitate new ecosystem management trajectories. By analyzing the emergence of an adaptive co-management initiative in Bali, the UNESCO World Heritage Cultural Landscape of Bali Province, this dissertation seeks to contribute to recent research on institutional governance approaches to enhance ecosystem management and social well-being. To that end, it addresses two questions. First, it identifies and explores three primary characteristics that fostered a new multi-level adaptive governance approach to cultural landscape management in Bali: the widespread perception of environmental crisis on the island that triggered collective action and the political will for a new form of ecosystem management; the emergence of a shared ideology--articulated in the Balinese Hindu philosophy of tri hita karana, or "the three causes of prosperity"--that unified diverse actors and actor networks and established a common platform for ecological resource management; and context-specific governance strategies that built on existing institutions and local-level initiatives. The second question centers on an analysis of the emergence of the management plan for the World Heritage site in Bali. The management plan was developed to support the Balinese subak in its struggle to adapt to current and future pressures that threaten to undermine the island's unique social-ecological system. For centuries, the subak have maintained Bali's terraced rice paddy landscape as a network of semi-autonomous irrigation associations, mediated through water temples. The adaptive co-management plan draws on principles of adaptive governance to connect subaks with other actors and actor groups across multiple institutional levels and regional jurisdictions. Research findings support the likelihood that the World Heritage initiative can promote transformative change in cultural landscape management in Bali. As the initiative develops, it will provide a fertile site for future research on adaptive governance, to better understand interdependent social-ecological relationships and the evolution of adaptive co-management approaches.
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Laura, Liliana Abril Garcia. "Population Dynamics of the Brown Planthopper Nilaparvata lugens (Stål) in Rice Fields in Thailand and Its Potential Applications to Pest Management." Kyoto University, 2018. http://hdl.handle.net/2433/232366.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第21165号
農博第2291号
新制||農||1060(附属図書館)
学位論文||H30||N5139(農学部図書室)
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 縄田 栄治, 教授 舟川 晋也, 教授 松浦 健二
学位規則第4条第1項該当
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Harris, Leah M. "Modeling a Cost-Effective IPM Dissemination Strategy for Vegetables and Rice: An Example in South Asia." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/33404.
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Integrated Pest Management (IPM) technologies have proven to be effective at increasing agricultural productivity and have been credited for providing economic, health, and environmental benefits in many developing countries. In South Asia, population growth and the increasing demand for nutritious foods have put pressure on farmers to produce more food with a relatively inelastic supply of land. Productivity enhancing practices, like IPM, have helped some farmers to meet this demand; however, with over 50 million farmers in Bangladesh and Nepal it is difficult to reach them with information about new agricultural technologies. This study evaluates the current IPM dissemination strategy being implemented by the Bangladesh Department of Agricultural Extension (DAE) and uses a linear programming (LP) model to propose alternative strategies that may extend the total benefits from IPM technologies. Additionally, using data from a household survey, a bivariate probit model and a two-step endogenous participation model are used to identify factors that may influence both knowledge and adoption of IPM practices in three regions of Nepal. The results from the LP model suggest that more farmers could be effectively reached by reallocating funding that is currently used for interpersonal communications (i.e. extension agent visits and farmer field schools) to more widespread methods such as mass media and field days. The model also suggests that a dynamic dissemination strategy is necessary to encourage adoption of IPM technologies with differing characteristics and levels of complexity. The econometric analysis suggests that farmers with â network linkagesâ to agricultural information and inputs, such as membership in a farmer organization, are more likely to be aware of IPM and to adopt IPM practices. The survey data also suggest that farmers who are members of Marketing Planning Committees (MPC) may be more likely to adopt more IPM practices when compared to non-members. Overall, the study suggests that strategically disseminating IPM information is vital to promote the adoption of these technologies in South Asia.Master of Science
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Massawe, Boniface Hussein John. "Digital Soil Mapping and GIS-based Land Evaluation for Rice Suitability in Kilombero Valley, Tanzania." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1437397073.
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Stürz, Sabine [Verfasser], and Folkard [Akademischer Betreuer] Asch. "Effects of Water Management on Microclimate and Yield Physiology in Irrigated Rice in Semi-arid Environments / Sabine Stürz. Betreuer: Folkard Asch." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2014. http://d-nb.info/1055990267/34.
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Mortele, Diovane Freire. "Efluxo de metano em solo sob manejos de irrigação e cultivares de arroz irrrigado." Universidade Federal de Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/3329.
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Conselho Nacional de Desenvolvimento Científico e TecnológicoHuman activity has been pointed out as the main reason of global warming by effluxes of CO2, N2O and CH4. In the last years, harmful effects of greenhouse gases due to its increase in atmosphere have been arousing interests of scientists into propose mechanisms of mitigation. Flooding rice is responsible for about 12% of CH4 released to atmosphere and therefore, is considerate one of the most important source of this greenhouse gas. There are many factors that control CH4 efflux in irrigated rice fields, which difficult an accurate identification of the responsible mechanisms. However, is known that irrigation regime and selection of rice cultivars affect CH4 efflux and may be managed intending to mitigate it. The objectives of this thesis were: (a) verify the effect of continuous irrigation, intermittent irrigation and intermittent flooding into CH4 efflux of a hapludalf soil cultivated with flooding rice at central region of Rio Grande do Sul State; (b) evaluate CH4 efflux of rice cultivated in greenhouse under different irrigation managements and relate the efflux to agronomic parameters of rice plants; (c) evaluate the irrigation systems over the rice crop and how it affect the electrochemical of soil solution and plant development; (d) evaluate CH4 efflux through cultivars of rice from Rio Grande do Sul and Santa Catarina States and relate it to plant morphological attributes. Intermittent irrigation was efficient to mitigate CH4 efflux in rice cultivations, when the lack of rain did not establish water layers, without having decrease in rice productivity. intermittent flooding management by irrigations, even at saturated soil, decreased the CH4 efflux by 70%. The management of intermittent flooding by irrigations when soil was bellow the field capacity do not cause CH4 efflux, however, this management caused decrease of rice productivity. Irrigation management does affect electrochemical conditions of soil, which are determinant to the CH4 production in soils. The dynamic of efflux of CH4 is similar between cultivars; however, there are differences on potential of CH4 efflux from cultivars of flooding rice. The cultivars Arize 1003, Avaxi Cl, BRS Atalanta, BRS Querência, BRS Taim, Inov Cl, Irga 422 and Irga 424 have showed lower efflux and higher productivities. Morphological characteristics of plants have not explained completely the differences of CH4 effluxes between cultivars.
A atividade antrópica tem sido apontada como a principal causa do aquecimento global pelo efluxo de CO2, N2O e CH4. Nos últimos anos, os efeitos prejudiciais do aumento da concentração atmosférica desses gases têm despertado os cientistas a propor mecanismos de mitigação. A cultura do arroz irrigado por alagamento é responsável por cerca de 12% do efluxo total de CH4 para a atmosfera, sendo considerada uma das principais fontes emissoras desse gás de efeito estufa. Os fatores que controlam o efluxo de CH4 no arroz irrigado são muitos, dificultando identificar com precisão os mecanismos responsáveis pelo seu efluxo. O regime de irrigação e a seleção de cultivares de arroz são fatores que afetam o efluxo de CH4 e podem ser modificados visando mitigar os efluxos para a atmosfera. Os objetivos da tese foram: (a) verificar o efeito do regime de irrigação contínua, intermitente e a banhos no efluxo de CH4 em um Planossolo cultivado com arroz irrigado por alagamento na Depressão Central do Rio Grande do Sul; (b) avaliar o efluxo de CH4 no arroz cultivado em casa de vegetação submetido a diferentes manejos de irrigação e relacionar o efluxo com parâmetros agronômicos da planta de arroz; (c) avaliar os sistemas de manejo de irrigação na cultura do arroz e os efeitos nos atributos eletroquímicos da solução do solo e no desenvolvimento das plantas; (d) avaliar o efluxo de CH4 em cultivares de arroz do RS e SC e relacionar com atributos morfofisiológicos das cultivares; e (e) caracterizar morfologicamente a cultura do arroz e verificar a provável rota de difusão do CH4 do solo até a atmosfera. A prática da irrigação intermitente foi eficiente em mitigar o efluxo de CH4 no cultivo do arroz irrigado quando as condições climáticas permitiram a ausência da lâmina de água durante o cultivo, sem diminuir a produtividade do arroz. O manejo da irrigação intermitente com o realagamento do solo ainda saturado diminuiu a emissão de CH4 em 70%. O manejo intermitente da irrigação com o realagamento do solo abaixo da capacidade de campo não causa efluxo de CH4, porém os efeitos foram negativos sobre a produtividade do arroz. O manejo da irrigação afeta as condições eletroquímicas do solo e são determinantes para a produção de CH4 nos solos. A dinâmica de efluxo de CH4 é semelhante entre as cultivares, porém, existem diferenças no potencial de efluxo de CH4 em cultivares de arroz irrigado por alagamento. As cultivares Arize 1003, Avaxi Cl, BRS Atalanta, BRS Querência, BRS Taim, Inov Cl, Irga 422 e Irga 424 apresentaram menor efluxo de CH4 com a maior produtividade do arroz. As características morfofisiológicas das plantas não explicaram completamente as diferenças de efluxos de CH4 entre as cultivares.
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Kameda, Chika. "Factors Influencing the Changes of Swidden Agriculture and Its Development in Rural Livelihoods of Northern Laos." Kyoto University, 2015. http://hdl.handle.net/2433/202730.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第19325号
農博第2146号
新制||農||1036(附属図書館)
学位論文||H28||N4953(農学部図書室)
32327
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 縄田 栄治, 教授 舟川 晋也, 教授 神﨑 護
学位規則第4条第1項該当
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Durigon, Reges. "Aplicação de técnicas de manejo localizado na cultura do arroz irrigado (oryza sativa l.)." Universidade Federal de Santa Maria, 2007. http://repositorio.ufsm.br/handle/1/3570.
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While in the traditional agricultural management soil attributes variability used in the crop production has not been considered, the site-specific management aims
to identify this variability. The main objective of the present work was to compare the site-specific management to the traditional management in the flooded rice crop
describing the techniques and identifying economical and technicals factors that provide a viability analysis. For this reason, an experiment was carried out in a
commercial flooded rice field with application of site-specific management techniques. The methodology consisted in the elaboration of soil attributes, management and yield maps and the correlations among these maps were used to elaborate maps of fertilizers application variable rate. The results showed variability in the flooded rice yield. The higgest positive correlations between the rice yield and soil attributes were verified for calcium and magnesium and the higgest negative correlations were for exchangeable aluminum and aluminum saturation. The
application of lime at variable rate reduced the total amount lime used when compared to the application at the fixed rate and increased the profit margin yield,
providing profitability of 71% with the operation. The results showed the technical and economical viability of use site-specific management techniques in the flooded rice
crop.Enquanto que no gerenciamento agrícola tradicional a variabilidade de atributos de solo utilizados na produção vegetal não tem sido considerada, o manejo localizado visa identificar esta variabilidade. O presente trabalho objetivou comparar o manejo localizado com o manejo tradicional na cultura do arroz irrigado, descrevendo as técnicas e identificando fatores técnicos e econômicos que proporcionam uma análise de viabilidade. Por esta razão, foi conduzido um experimento em uma lavoura comercial de arroz irrigado com aplicação de técnicas de manejo localizado. A metodologia consistiu na elaboração de mapas de atributos de solo, manejo e produtividade da cultura e as correlações entre estes mapas foram utilizadas para elaborar mapas de aplicação de fertilizantes à taxa variável. Os resultados mostraram variabilidade na produtividade de arroz irrigado. As maiores correlações positivas entre produtividade de arroz e atributos de solo foram verificadas para cálcio e magnésio e as maiores correlações negativas para alumínio trocável e saturação por alumínio. A aplicação de calcário em taxa variável reduziu a quantidade de calcário necessária comparada à aplicação em taxa fixa e incrementou a margem líquida na produção, proporcionando uma lucratividade de 71% com a operação. Os resultados mostram viabilidade técnica e econômica para utilização das técnicas de manejo localizado na cultura do arroz irrigado.
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Green, Madeleine. "Water management for agriculture under a changing climate: case study of Nyagatare watershed in Rwanda." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-391355.
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Sub-Saharan Africa is today facing a big challenge regarding food deficiency and water scarcity due to climate change. One of these countries is Rwanda, a small landlocked country in the middle of Africa. Rwanda strongly depend on agriculture, both in the aspect of reducing poverty and hunger but also because their economy security depend on it. Because of increasingly fluctuating rainfalls their agriculture becomes more dependent on irrigation and the availability to water resources. To investigate how the climate change will affect the amount of water resources in the coming decades, this study is focusing on the watershed and marshland of Muvumba P8 in Nyagatare, Rwanda. A hydrological model was created, in a software called Soil and Water Assessment Tool (SWAT), with soil, land use and slope maps for the watershed. Calibrating the model was done with help of Climate Forecast System Reanalysis (CFSR) data and run for nine different climate model datasets. An uncertainty had to be taken into account regarding both the measured local data and the downloaded data. To be able to compare the amount of water resources and the irrigation requirements for the rice crop the farmers were growing on the marshland, the crop water requirements for rice was estimated with FAO’s program called CROPWAT. The irrigation system on the marshland allows a double cropping of rice every year and consist of a system depending on elevation differences to create natural fall. There was three reservoirs along the marshland but to limit the project, only the first reservoir was taken into account. This was complemented with existing data and field survey. Six out of nine climate models showed a decrease in median discharge over the coming 30 years compared to the CFSR historical median discharge. This means that less water in general will reach the outlet of the watershed in the years to come. At the same time all climate models indicate an increase in irrigation requirements for the rice crops. The seasons are probably going to change, a longer and drier season between June and August and a rainier season between September and November are projected.
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Nguyen, Thi Binh [Verfasser], Manfred [Akademischer Betreuer] Boltze, and Hanno [Akademischer Betreuer] Friedrich. "A Multi-Stage Impact Assessment Method for Freight Transport Management Measures – The Example of Vietnamese Rice Production and Logistics / Binh Nguyen Thi ; Manfred Boltze, Hanno Friedrich." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2017. http://d-nb.info/1137324023/34.
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Finger, Maria Isabel Fernandes. "Percepção e medidas de gestão de riscos por produtores de arroz irrigado na Fronteira-Oeste do Rio Grande do Sul." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/49362.
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A produção agrícola apresenta características particulares, se comparada a outras atividades da economia, sendo uma das mais marcantes a extensão dos riscos aos quais está exposta. O cultivo de arroz (Oryza sativa L.) irrigado, embora pareça menos suscetível a riscos do que as culturas de sequeiro, também está exposto aos riscos inerentes ao exercício da atividade agrícola. Maior produtor mundial de arroz fora da Ásia, o Brasil tem no estado do Rio Grande do Sul seu principal estado produtor, com 65% do total. O objetivo deste trabalho foi analisar como o orizicultor do Rio Grande do Sul percebe os riscos inerentes à sua atividade e quais medidas adota para gerir estes riscos. O método empregado envolveu a aplicação presencial de questionários semiestruturados em orizicultores, de acordo com uma amostra não probabilística definida. Os resultados indicaram que os orizicultores atribuem maior relevância aos riscos socioeconômicos do que aos de produção, na percepção atual. Quando comparada a percepção atual dos orizicultores em relação à de cinco anos atrás, observou-se um aumento da relevância dos riscos de mercado e institucionais. Evidencia-se, assim, a importância da gestão do negócio por parte dos orizicultores do Rio Grande do Sul, para que sua atividade produtiva esteja organizada de modo a ocorrer de forma integrada com os demais elos da cadeia produtiva do arroz. A menor relevância atribuída pelos orizicultores aos riscos de produção, na percepção atual, pode indicar que as técnicas produtivas já estejam consolidadas. Em se tratando de medidas de gestão de riscos, a busca de informação é adotada pela maioria dos orizicultores e foi considerada relevante; no entanto, há indicativos de que a aplicação desta informação ainda pode ser melhorada. Os orizicultores percebem a importância e a necessidade de reduzir custos sem, no entanto, formalizar a maneira de fazê-lo. A redução de custos pode ser uma alternativa para mitigação de riscos de mercado, apontados como os mais relevantes pelos orizicultores. A percepção dos orizicultores sobre as fontes de risco inerentes à sua atividade e sobre as medidas para mitigá-las pode representar o alicerce na formulação de estratégias de gestão de riscos.Agricultural production has many different influencing factors compared to other economic areas. One of the most striking is the extent of the risks to which it is exposed. Irrigated rice (Oryza sativa L.) cultivation, although seeming less susceptible to risk than non-irrigated crops, is also exposed to risks related to agricultural practices. World's largest producer of rice outside Asia, Brazil has the state of Rio Grande do Sul as its main producer, reaching 65% of the total amount. The aim of this study was to analyze how rice farmers in Rio Grande do Sul realize the risks of their activity and what measures they take to manage such risks. Methodology involved the administration of a semi-structured questionnaire with rice farmers, according to a non-probabilistic sample. The results indicated that rice farmers attach greater relevance to economic and social risks in their current perception, rather than to production related ones. Comparing rice growers’ current perception with that of five years ago, an increase on the relevance of market and institutional risks was observed. Thus, one realizes the importance of business management by rice farmers in Rio Grande do Sul, in order to organize their activity to take place in an integrated manner with others links of the rice production chain. The lowest relevance ascribed to production-related risks in the current perception may indicate that production techniques have already been consolidated. Regarding measures for risk management, information seeking is adopted for most rice farmers and was considered relevant; however, there is evidence that the applicability of this information can still be improved. Rice growers realize the importance and the need to reduce costs without, however, formalizing a way of doing it. Costs reduction may be an option to mitigate market risks, identified as the most relevant by the rice growers. Rice growers´ perception on the risk sources inherent to their activity and on measures to mitigate them may represent the foundation for formulating risk management strategies.
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Nguyen, Vo Chau Ngan, Thi Ngoc Luu Huynh, Hoang Viet Le, Ngoc Quynh Do, and Ngoc Em Nguyen. "Pollution minimizing at traditional craft village by micro-credit program - case study from Tan Phu Dong rice flour production village." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-99186.
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This paper introduces the results of a project initiated by Cantho University (CTU) on the introduction of micro-credits for addressing the environmental pollution in Vietnam’s craft villages. At Tan Phu Dong, a traditional rice powder production village in Sa Dec, Dong Thap, all wastes from domestic and production activities and animal husbandry were freely disposed into open water sources. This practice led to a negative impact on the local environment. With the financial support provided by the Bread for the World (BfdW), a micro-credit program was initiated in which farmers could borrow money to construct a biogas plant to treat animal husbandry and domestic wastes. In addition, the staff transferred biogas plant construction technology to the local masons and organized training courses on biogas plant operation and maintenance and biogas usage for the farmers and the local officials. 61 farmers borrowed money from the program to construct their biogas plants, followed by more than 250 farmers that constructed their biogas plants by their own finance after realizing the positive benefits of biogas plants. As result, the environmental pollution issue was solved step-by-step, thereby helping enhance the living conditions of the local communityBài báo này trình bày biện pháp sử dụng nguồn quỹ tín dụng nhỏ để các hộ dân cải thiện tình trạng ô nhiễm môi trường ở các làng nghề Việt Nam. Tại làng nghề làm bột Tân Phú Đông - Sa Đéc - Đồng Tháp, các loại chất thải sinh hoạt, chất thải sản xuất và chăn nuôi xả thải bừa bãi đã gây ô nhiễm môi trường nghiêm trọng. Với kinh phí tài trợ từ tổ chức Bánh mỳ cho thế giới (BfdW), các cán bộ trường Đại học Cần Thơ đã tổ chức cho người dân luân phiên vay vốn để xây dựng hầm ủ khí sinh học xử lý chất thải chăn nuôi và chất thải sinh hoạt. Bên cạnh đó còn tổ chức các lớp tập huấn chuyển giao công nghệ xây hầm ủ khí sinh học cho thợ xây địa phương, hướng dẫn vận hành và bảo dưỡng hầm ủ cho người dân và cán bộ địa phương. Thông qua nguồn vốn vay của dự án, có 61 hộ dân đã xây dựng hầm ủ khí sinh học và trên 250 hộ dân khác đã tự đầu tư xây dựng khi thấy được lợi ích của hầm ủ. Nhờ đó tình trạng ô nhiễm môi trường từng bước được giải quyết góp phần cải thiện điều kiện sống của người dân tại địa phương
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Dao, Trong Hung [Verfasser], Daniela [Akademischer Betreuer] Sauer, Daniela [Gutachter] Sauer, and Markus [Gutachter] Keck. "Management Options for Optimizing Nutrient Cycling and Reducing Greenhouse Gas Emissions from Smallholder Rice Farms in Vietnam / Hung Dao Trong ; Gutachter: Daniela Sauer, Markus Keck ; Betreuer: Daniela Sauer." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1200209222/34.
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Hung, Dao Trong [Verfasser], Daniela [Akademischer Betreuer] Sauer, Daniela [Gutachter] Sauer, and Markus [Gutachter] Keck. "Management Options for Optimizing Nutrient Cycling and Reducing Greenhouse Gas Emissions from Smallholder Rice Farms in Vietnam / Hung Dao Trong ; Gutachter: Daniela Sauer, Markus Keck ; Betreuer: Daniela Sauer." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1200209222/34.
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Cunha, Christhian Santana. "ANÁLISE DE CENÁRIOS COM REDUÇÃO DA DEMANDA DA ORIZCULTURA NA BACIA DO RIO SANTA MARIA COM APLICAÇÃO DO MODELO CRUZ." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/7859.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe demand for water in the various sectors of society is increasing due to factors such as population growth, expansion of agricultural land, depletion of water resources and water quality decreased. Among these uses these demands arise that there are two groups of water, consumptive and non-consumptive. Consumptive uses are characterized by causing a change in the quantity or quality of water, either through funding or evictions. Non-consumptive uses do not cause significant changes in the quantity and quality of water, but depend on these to be realized. The irrigation of rice is a consumptive use that is considered high pollution impact by demanding too much water in their production process. The Rio Grande do Sul is responsible for approximately 65% of rice production in Brazil. The watershed of the river Santa Maria, is characterized by having focused their economic bases for rice cultivation and livestock. In the past there have been conflicts over water use between sectors of users of the basin (water supply and irrigation). Thus, this paper proposes the creation of scenarios with the gradual reduction in a range of 1% to 15% in the demand of water for irrigation of rice in funding of water held in the rivers in BHRSM. With the aim of analyzing the results proposed to the management of water demand can assist and serve as input for the process of water resources management. Initially 5 scenarios, Scenario 0, which characterizes the present moment basin, Scenario 1, 2, 3 and 4 which have as a methodological proposal to reduce the demand for water for irrigation were built. The results obtained in this work allow us to analyze the management of water demand can help to increase water availability. The scenarios simulated for the months from November to February showed the highest percentage of attendance when compared to current demand. However, the month of January still has some hydrological drought in reference sections, being necessary to think about rationing or the use of available water in existing reservoirs in the basin. It is estimated that the results obtained with the simulation in demand management, can support the management of water resources of the basin.
A demanda por água nos diversos setores da sociedade vem aumentando devido a fatores como: crescimento populacional, expansão das áreas agrícolas, esgotamento dos recursos hídricos e diminuição da qualidade água. Entre estes usos que originam estas demandas de águas existem dois grupos, os consuntivos e não consuntivos. Os usos consuntivos caracterizam-se por causarem alguma alteração na quantidade ou qualidade da água, seja por meio de captações ou despejos. Os usos não consuntivos não causam alterações significativas na quantidade e qualidade da água, porém dependem destas para serem realizados. A irrigação de arroz é um uso consuntivo que é considerado de alto impacto poluidor por demandar muita água no seu processo produtivo. O Rio Grande do Sul é responsável por aproximadamente 65% da produção de arroz no Brasil. A Bacia Hidrográfica do rio Santa Maria, caracteriza-se por ter suas bases econômicas voltadas para orizicultura e pecuária de corte. No passado existiram conflitos pelo uso da água entre os setores de usuários da bacia (abastecimento e irrigação). Desta forma, este trabalho propõe a criação de cenários com a redução gradual, em uma escala de 1% a 15% na demanda de água destinada a irrigação do arroz, nas captações de águas realizadas nos rios na BHRSM. Com o objetivo de analisar se os resultados propostos com a gestão da demanda de água podem auxiliar e servir como subsídios para os processos de gestão de recursos hídricos. Foram construídos inicialmente 5 cenários, o Cenário 0, que caracteriza o momento atual da bacia, Cenário 1, 2, 3 e 4 que possuem como proposta metodológica a redução na demanda de água destinada a irrigação. Os resultados obtidos com neste trabalho permitem analisar que a gestão da demanda de água pode auxiliar no aumento da disponibilidade hídrica. Os cenários simulados para os meses de novembro a fevereiro apresentaram percentuais de atendimento da demanda maiores quando comparado ao atual. No entanto, o mês de janeiro ainda apresenta déficit hídrico em algumas seções hidrológicas de referência, sendo necessário pensar em racionamento ou a utilização das águas disponíveis em reservatórios já existentes na bacia. Estima-se que os resultados obtidos com a simulação na gestão da demanda, possam subsidiar o gerenciamento dos recursos hídricos da bacia.
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Rehberger, Bescos Irene. "Sustainable Livelihood Analysis of an Irrigation Project in Ta Haen, Cambodia." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4395.
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This study examines potential livelihood outcomes from a recently established irrigation project in Ta Haen, Cambodia, in a sustainable livelihoods framework. The aim of this SAUCE irrigation project is to provide water for drinking and irrigation purposes with the goal of enhancing food by producing an extra rice harvest, the staple, per year. Field research conducted in December 2011 provided qualitative data from questionnaires, key informant interviews, and participant and direct observation, in addition to quantitative data from water quality analysis focusing on arsenic (a potential risk), pH, EC and temperature. Most of the people in the village did not obtain an extra rice harvest in this first year of the project. However, they did plant other crops along the Ta Haen riverbanks. Average arsenic concentration was 32 ppb, above WHO guideline value (10 ppb). However, dose response data is uncertain at levels below 50 ppb, which makes river water use acceptable given that this is a major water source for the community. Preliminary results suggest that project sustainability and positive livelihood outcomes depend upon improving overall agricultural and water management practices by addressing quality issues, rationing water, and removing invasive water hyacinths that affect water quantity.
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Rodríguez, María del Carmen Herrera. "Utilização de extrato padronizado e óleo essencial de rosmarinus officinalis l. (Lamiaceae) no controle da brusone (Magnaporthe oryzae) do arroz (Oryza sativa L. - Poaceae)." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/8634.
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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Fungicides consumption was increased in recent years for control of rice blast, causing various problems, such as increased production costs, the development of resistance to the pathogen, the presence of residues in foods. This leads to the need to develop new methods and strategies of control of the disease and the application of plant extracts and essential oils. The objective of this study was to evaluate in vitro and in vivo antimicrobial activity of standardized extract in rosmarinic acid and essential oil of Rosmarinus officinalis on Magnaporthe oryzae. Were evaluated in vitro concentrations 50, 45, 40, 35, 30, 25, 20, 15, 10, 5 and 0 mg/mL of the concentrated extract 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.5 and 0 μL/mL, of essential oil and 1.05, 0.945, 0.81, 0.735, 0.63, 0.525, 0.42, 0.315, 0.21, 0.105 and 0 mg/mL of rosmarinic acid on the mycelial growth Inhibition of germination, apressorium formation and the effect on the plasmatic membrane were performed in concentrations 50, 40, 30, 20, 10, 5, 2.5 and 0 mg/mL of extract, 1.05, 0.84, 0.63, 0.42, 0.21, 0.105, 0.052 and 0 mg/mL of rosmarinic acid and 0.05, 0.04, 0.03, 0.02 and 0 μL/cm3 of essential oil. In vivo were tested concentrations 150, 100, 50 and 0 mg/mL of extract and 6.3, 4.2, 2.1 e 0 mg/mL of rosmarinic acid. The best concentrations that inhibited mycelial growth were 50, 45, 40 and 35 mg/mL and 5 4.5, 4 and 3.5 μL/mL of extract and essential oil, respectively, but rosmarinic acid had an inhibitory effect at the concentrations of 0.945 and 1.05 mg/mL. On the other hand, the concentrations of 40 and 50 mg/mL of the extract and the concentration of 0.21, 0.42, 0.63, 0.84 and 1.05 mg/mL rosmarinic acid and all the essential oil concentrations inhibited the germination and the formation of the apressorium 4, 6 and 24 hours without damaging the plasmatic membrane and cell wall of conidia of M. oryzae. In vivo, all treatments of extract reduced the severity of rice blast, with a optimal concentration of 150 mg/mL reducing above 90% of the disease, rosmarinic acid no showed inhibitory effect.
O consumo de fungicidas para o controle da brusone do arroz aumentou nos últimos anos, gerando vários inconvenientes, tais como aumento dos custos de produção, o desenvolvimento de resistência do patógeno e a presença de resíduos em alimentos. Isto leva à necessidade de desenvolver novos métodos e estratégias para o controle desta doença como o uso de extratos vegetais e óleos essenciais. O objetivo deste trabalho foi avaliar in vitro e in vivo a atividade antimicrobiana do extrato padronizado em ácido rosmarínico e do óleo essencial de Rosmarinus officinalis sobre Magnaporthe oryzae. O material vegetal foi caracterizado de acordo com a Farmacopeia Brasileira 5° edição. O óleo essencial foi obtido por hidrodestilação em aparelho de Clevenger e os constituintes foram identificados por Cromatografia gasosa acoplada a espectrometria de massas. A quantificação do ácido rosmarínico no extrato foi realizada por cromatografia líquida de alta eficiência (CLAE) e a metodologia analítica foi validada. Os testes de atividade antimicrobiana foram realizados in vitro e in vivo, a partir de um delineamento inteiramente casualizado. In vitro foram avaliadas as concentrações de 50, 45, 40, 35, 30, 25, 20, 15, 10, 5 e 0 mg/mL do extrato concentrado, 5; 4,5; 4; 3,5; 3; 2,5; 2; 1,5; 1; 0,5 e 0 μL/mL do óleo essencial e 1,05; 0,945; 0,81; 0,735; 0,63; 0,525; 0,42; 0,315; 0,21; 0,105 e 0 mg/mL do ácido rosmarínico sobre o crescimento micelial. A inibição da germinação, formação do apressório e o efeito sobre a membrana plasmática foram realizados nas concentrações de 50, 40, 30, 20, 10, 5, 2,5 e 0 mg/mL de extrato; 0,105; 0,84; 0,63; 0,42; 0,21; 0,105; 0,052 e 0 mg/mL do ácido rosmarínico e 0,05; 0,04; 0,03; 0,02 e 0 μL/cm3 de óleo essencial. In vivo foram testadas as concentrações de 150, 100, 50 e 0 mg/mL do extrato e 6,3; 4,2; 2,1 e 0 mg/mL do ácido rosmarínico. As melhores concentrações que inibiram o crescimento micelial foram 50, 45, 40 e 35 mg/mL e 5; 4,5; 4 e 3,5 μL/mL de extrato e de óleo essencial respectivamente, porém o ácido rosmarínico apresentou o efeito inibitório apenas nas concentrações de 0,945 e 1,05 mg/mL. Por outro lado, as concentrações de 40 e 50 mg/mL do extrato e as concentrações de 0,21; 0,42; 0,63; 0,84 e 1,05 mg/mL de ácido rosmarínico e todas as concentrações do óleo essencial inibiram a germinação e a formação do apressório as 4, 6 e 24 horas, sem contudo, causar dano a parede e membrana plasmática dos conídios de M. oryzae. In vivo, todos os tratamentos com extrato reduziram a severidade da brusone foliar, destacando-se 150 mg/mL, que reduziu em mais de 90% da área foliar afetada. O ácido rosmarínico não apresentou efeito inibitório da severidade da brusone foliar.
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Lundberg, Mats. "Kinh Settlers in Viet Nam’s Northern Highlands : Natural Resources Management in a Cultural Context." Doctoral thesis, Linköpings universitet, Tema vatten i natur och samhälle, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-4778.
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This study deals with the Kinh (or Viet) majority people who have migrated from the lowland Red River Delta to the mountainous areas of northern Viet Nam, and their adjustment to a new social and physical environment. Its aim is to analyse the social and cultural consequences for these migrants when settling in communities populated with people who belong to the national ethnic minorities (the Tày, the Giay and the Ngan peoples). Focus is on impacts in new interactive situations. The case is a special one in that it focuses on majority people's adaptation to minorities, and to a lesser extent vice versa. The Kinhs' view of how a "civilised" landscape ought to look like and how to utilise the natural resources therein demonstrated to be a central theme when discussing restructuring of the migrants' livelihood. This fact indicates the cultural dimension in the exploitation of the natural landscape and the reconstruction of the subsistence system. In the process of adaptation to a new social environment (as well as to a new physical one), social interactions between the Kinh and the ethnic minorities have proven to be important steps towards integration. One factor that turned out to be decisive in the integration process is the harmonising of life cycle ceremonies (especially weddings and funerals) between the Kinh and the minorities. New knowledge is accumulated locally, based on pooled experience. The study concerns how new knowledge on natural resources management is formed through a mixture of the migrants' knowledge from the Red River Delta and the minorities' knowledge of the local area. With a background in the delta area the Kinh brought the old knowledge of advanced wet rice production with them when migrating to the highlands. The facts show that the influence on the subsistence system has not been a one-way flow. That is, not only has the Kinh changed the minorities' agriculture system, but also the minorities' systems have had an impact on the Kinhs' system so that it now is more adapted to the conditions in the highlands.
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Andrade, Isabel Cristina Barreto. "Diagnóstico da rizicultura na foz do rio São Francisco sob a perspectiva de um modelo sustentável de gestão." Universidade Federal de Sergipe, 2016. https://ri.ufs.br/handle/riufs/4225.
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Fundação de Apoio a Pesquisa e à Inovação Tecnológica do Estado de Sergipe - FAPITEC/SEVarious fields of knowledge discuss the classical model of economic development and the impact on life on the planet. These settings cause multiple demands on enterprises and invoke a restructuring of the management models adopted by these. The environmental and economic responsibility has become a term discussed in the academic world, this event directed the society towards sustainability. In this thesis, using the approach: economic, social and environmental, we reached the conclusion that sustainable development implies a link between the natural social sciences. In this context, the main purpose of this thesis was to develop a sustainable management model (PSG) which has views to profitability; the proper management of natural resources, and improve the quality of life of the different actors involved in a project, this one is of any kind. taking as a basis for the understanding of this study, we investigated the perimeter of the irrigated lots of rice farmers - the lower San Francisco - the city of Flores Island / SE, 135 km from Aracaju / SE. Using management tools and indicators: environmental; social and economic allies to secondary data. Within this context, it was possible to specifically examine: the use and occupation of the basin; the physical medium - water; identify the perpetrators members from human activities; ascertain the feasibility of the proposed model; contribute to public policy. The method was based on a systemic approach. It was exploratory in nature; descriptive; field, experimental and documentary. Approach quantitative and qualitative. Data collection: semi-structured questionnaire and interviews - were analyzed according to the content of Bardin. Thus, it is expected to collaborate: with the academic community adding an interdisciplinary approach new contributions in environmental sciences; rationale and implementation of public policies. Therefore, it was demonstrated that, by inserting the sustainable PSG management is possible to manage quality and a production process liquid (either agricultural or not), particularly, minimizing environmental impact; generating wealth and, consequently, rising the quality of life of the actors involved in the process in question.
Varias áreas do conhecimento discutem o modelo clássico de desenvolvimento econômico e os impactos sobre a vida no planeta. Estas colocações provocam múltiplas demandas sobre os empreendimentos e invocam uma reestruturação dos modelos de gestão por estes adotados. A responsabilidade socioambiental e econômica se tornou um termo discutido no universo acadêmico, esta circunstância direcionou a sociedade no caminho da sustentabilidade. Nesta tese, utilizando-se da abordagem: econômica, social e ambiental, chegou-se a conclusão de que o desenvolvimento sustentável implica numa articulação entre as ciências sociais naturais. Nesse contexto, a finalidade principal desta Tese foi o de desenvolver um Plano sustentável de gestão (PSG) que tenha vistas para a lucratividade; o manejo adequado dos recursos naturais, e melhore a qualidade de vida dos diferentes atores envolvidos em um empreendimento, este, seja de qualquer natureza. Tomando-se como base para a compreensão deste estudo, foi pesquisado o perímetro dos lotes irrigados dos rizicultores – no baixo São Francisco – no município de Ilha das Flores/ SE, a 135 km de Aracaju/SE. Utilizando-se ferramentas de gestão e indicadores: ambientais; sociais e econômicos aliados a dados secundários. Dentro deste contexto, foi possível especificamente analisar: o uso e ocupação da bacia; o meio físico – água; identificar os elementos agressores oriundos de ações antrópicas; averiguar a viabilidade do modelo proposto; contribuir com as políticas públicas. O método foi baseado em um enfoque sistêmico. Foi de natureza exploratória; descritiva; de campo, experimental e documental. Abordagem quanti-qualitativa. A coleta dos dados: questionário semiestruturado e entrevistas – foram analisados de acordo com o conteúdo de Bardin. Assim, espera-se colaborar: com a comunidade acadêmica acrescentando de modo interdisciplinar novas contribuições nas ciências ambientais; fundamentação e a implementação de políticas públicas. Portanto, demonstrou-se que, através da inserção do PSG- plano sustentável de gestão é possível gerenciar com qualidade e liquidez um processo produtivo (seja agrícola ou não), principalmente, minimizando impactos ambientais; gerando riquezas, e consequentemente, elevando-se a qualidade de vida dos atores envolvidos com o processo em questão