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1

Wigley, Georgina M. "Constraints on soil conservation in the Pindars River and Two Meetings Watersheds, Jamaica." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=64098.

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2

Cluett, Jonathan Paul. "Soil and sediment-based cultural records and The Heart of Neolithic Orkney World Heritage Site buffer zones." Thesis, University of Stirling, 2007. http://hdl.handle.net/1893/357.

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The designation of World Heritage Sites (WHS) by UNESCO is the principal international and formally recognised strategy allowing the conservation of sites of outstanding cultural value throughout the world. This study demonstrates that soils and sediments influenced by cultural activities retain cultural records (soils and sediments-based cultural records, hereafter abbreviated to SSBCR) associated with WHS, and further the understanding and contribute to the cultural value of WHS. Considering The Heart of Neolithic Orkney WHS and its surrounding landscape as the study location, systematic fieldwork is combined with geoarchaeological analyses including soil organic matter content, pH, particle size distribution, phosphorus concentration, soil magnetism and thin section micromorphology to determine the nature of the SSBCR. Chronologies of the formation of SSBCR and of palaeo-environmental records were ascertained using radiocarbon analyses and optically stimulated luminescence analysis. Findings of particular importance to the interpretation of the WHS are the identification of a Late Neolithic SSBCR located between the WHS monuments. This SSBCR is a valuable cultural record of a specific Late Neolithic community and provides significant insight into the interaction between settlement and ritual aspects of the Orcadian Late Neolithic. An understanding of these interactions is of crucial importance to a fuller interpretation of the WHS and to the wider discussion of the Orcadian Neolithic. The implications of this research to other WHS designated for their cultural value are discussed, together with future conservation considerations for this specific WHS.
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3

Acott, Timothy G. "Soil micromorphology and image analysis : a study of Bronze Age to recently improved soils at Lairg, Sutherland, Scotland." Thesis, University of Stirling, 1993. http://hdl.handle.net/1893/1784.

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The applications of multispectral and morphometric image analysis to soil thin section descriptions is examined. It is shown that unsupervised classification and contrast stretching can be used to enhance and label features of interest. Morphometric measurements, allow the shape and abundance of features in thin sections to be compared and statistical relationships established. This method of analysis offers a precision beyond that which is possible using a qualitative approach. Using soil micromorphology as the main analytical technique a case study was carried out to evaluate the applicability of image analysis to an investigation of an archaeological site at Lairg in northern Scotland. The interactions of anthropogenic activity and pedogenesis since the Bronze Age is examined. The condition of the soils prior to the Bronze Age is not known because no buried soils predated this period. Evidence suggests that in freely draining situations complete podzols might have formed by this time. During the Bronze and Iron Age intensive cultivation of soils occurred with associated erosion. In areas of the site, where human activity is dated to the Post Medieval period, deepening of A horizons is apparent and the soils are maintained as Brown Podzols. In many areas where human activity stops stagnopodzols are the dominant soil type. The potential of image analysis to aid soil micromorphological descriptions is demonstrated. Contrast stretching aided a qualitative subdivision of thin section slides during the case study. Morphometric analysis confirmed a relationship between shape of voids and c/f ratios in an Iron Age buried A horizon, A PM buried A horizon and an undated deep topsoil. It is concluded that the full benefits of image analysis, when used as a routine tool to aid thin section descriptions, will only be realised when procedures become more interactive and processes can be speeded up.
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4

Lloyd, Davidson A. "The effect of forest to pasture conversion on soil biological diversity and function." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/711.

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Recent declines in returns from primary forest products in New Zealand and projected increases in world food prices have led to the land-use conversion from plantation forest to pastoral farming in many lowland areas. After decades of forest cover the soils are in many cases less than adequate for pastoral farming, as they are acidic, with toxic levels of exchangeable aluminum, and contain low levels of available nitrogen (N), very high carbon (C):N ratio, and are devoid of earthworms and structural integrity. Overcoming the major site limitations of low soil pH and available N was a major priority and a field experiment was established in April 2005 to determine the impact of various rates of lime and N in relation to pasture establishment and production. Concerns about the short and long-term effects of these inputs on biological soil quality gave rise to the present study. The effects of land-use change and establishment inputs were assessed by comparison of selected treatment plots with two adjacent reference sites (long-term pasture and a 60–year Pinus radiata forest) on the same soil type. The effects of lime and N on soil biological quality were investigated under field and controlled environment conditions by determination of: microbial community structure (phospholipid fatty acids - PLFA), microbial biomass (total PLFA), and microbial activity (dehydrogenase activity). Soil physical (percentage water-stable aggregates) and chemical (pH, and total C and N) properties were also determined. Similarly, the effects of earthworm addition on soil biological properties were explored in a short-term glasshouse pot experiment. The role of earthworms as indicators of soil biological quality in the field was assumed by nematodes and these were assessed in field trial plots and the reference sites mentioned above. Land-use change and applications of lime and N contributed to changing the microbial community structure determined by principal component analysis of transformed PLFA data. However, the effect of lime was more pronounced in the field, while N contributed most to changing microbial community structure in the glasshouse. Mean microbial activity in the field increased from 4 µg dwt/hr without lime to 16 and 21 µg dwt/hr where lime was applied at 5 and 10 tons/hectare (t/ha), respectively. Mean microbial activity in the field was markedly higher (7-fold) than in the glasshouse at similar rates of lime. Lime application also increased soil moisture retention in the field, mean gravimetric soil moisture increased from 0.33 in control plots to 0.38 and 0.39 in plots treated with 5 and 10 t/ha lime, respectively. Lime application was associated with greater soil aggregate stability. Soils from test plots treated with 5 and 10 tons/ha lime had 45-50% water-stable aggregates compared to 34% in treatments without lime. After 16 weeks in pots, earthworm treatments increased mean plant dry matter (DM)/pot by at least 19% above the control. The increase was attributed primarily to greater N mineralization in the presence of earthworms. For the duration of the trial the earthworm species tested (Apporectodea caliginosa and Lumbricus rubellus, individually or combined) did not affect any of the measured soil microbial properties. However, the survival rate of A. caliginosa was 83% compared to 25% for L. rubellus. The control not receiving any lime or N and plots treated with 10t/ha lime and 200 kgN/ha had similar nematodes species composition, comprising 40% each of bacterial and fungal feeding nematodes. They differed markedly from the reference sites as the forest soil was dominated by plant associated species (38%) and the long-term pasture had 44% plant parasitic nematodes. Accordingly, the soil food web condition inferred from nematode faunal analysis characterized all test plots as basal, stressed and depleted, while the forest soil was categorized as highly structured and fungal dominated. The findings of this thesis demonstrated that land-use change from forest to pasture can have significant impacts on soil biological properties, earthworms can contribute to pasture productivity even in the short term, and nematode faunal analysis is a robust and reliable indicator of soil biological quality.
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5

Samsoedin, Ismayadi. "Biodiversity and sustainability in the Bulungan Research Forest, East Kalimantan, Indonesia : the response of plant species to logging." Thesis, University of Stirling, 2007. http://hdl.handle.net/1893/224.

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This study reports forest structure, regeneration and the soil properties from unlogged and logged forest in the Bulungan Research Forest, Malinau District, East Kalimantan, Indonesia. Four sites were compared by using four 1-ha replicate plots in each of primary forest (PF), 5, 10 and 30-yr old logged forest (LF-5, LF-10, LF- 30). The tree species composition differ among forest types, as it was shown that the mean value of similarity indices for all pairs were 0.215 (for the Jaccard index) and 0.353 (for the Sorensen index). The low values for similarities among forest types were most probably caused by low numbers of species shared between each forest type. Both correlation values, r = 0.023 for Jaccard index and r = 0.031 for Sorensen index, showed no strong correlation between the similarity index (C) and the distance between forest types. This supports the use of a chronosequence approach. A total of 914 tree species with ³ 10 cm dbh were recorded from 223 genera and 65 families. There were no significant differences in mean species numbers (166 – 180/ha) among treatments. Mean density of species was lower in LF-5 and LF-10 (501/ha) than in PF or LF-30 (605/ha and 577/ha); similarly to mean basal area (LF-5, 28.5 m2/ha; LF-10, 32.6 m2/ha) vs. PF (45.8 m2/ha) and LF-30 (46.9 m2/ha). Dead wood on the forest floor was significantly higher in LF-10 (75 m3/ha) than in the other treatments. Seedlings (< 2 cm dbh) of 1,022 species were recorded from 408 genera and 111 families. The mean number of tree seedling species ranged between 170-206; the mean density of seedlings was about two-fold lower in LF-10 (2790/ha) than in the other treatments. Saplings (>2 – 9.9 cm dbh) of 802 species belonged to 241 genera and 65 families. There was a high variability in species richness across treatments (89 – 191/ha), but not in stem numbers. The Dipterocarpaceae family was dominant in all treatments, followed by the Euphorbiaceae. The soils were acidic, low in nutrients and had low to very low fertility. Both primary and logged forest areas are marginal or not suitable for sustained production of plantation crops. Logging caused soil compaction in LF-30. Although in terms of number of species and trees, amount of BA, number of saplings and seedlings LF-30 appeared to have satisfied prescriptions for a second harvest, ecologically the forest is far from mature. The Indonesian Selective Cutting and Replanting (TPTI) system may need to be revised to a 35 – 45 year cycle to ensure long-term forest productivity in terms of not only timber but other goods and ecosystem services, the value of which are never quantified in monetary terms, but can be higher than the timber revenue.
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6

Jacometti, Marco Alexander Azon. "Enhancing ecosystem services in vineyards to improve the management of Botrytis cinerea." Phd thesis, Lincoln University. Bio-Protection and Ecology Division, 2007. http://theses.lincoln.ac.nz/public/adt-NZLIU20070126.115223/.

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Organic mulches and cover crops mulched in situ were assessed for their effects on B. cinerea primary inoculum and disease levels in inflorescences at flowering and/or bunches at harvest. Organic mulches were used to enhance biological degradation of vine debris to reduce levels of B. cinerea primary inoculum the following season. Four mulch types (anaerobically and aerobically fermented marc (grape pressings), inter-row grass clippings and shredded office paper) were applied under ten-year-old Riesling vines in a ten-replicate randomized block design in New Zealand over two consecutive years. Plastic mesh bags, each containing naturally infected vine debris, were placed under vines on bare ground (control) and at the soil-mulch interface, in winter (July) 2003 and 2004. In each year, half the bags were recovered at flowering (December) and the remainder at leaf plucking (February), for assessment of B. cinerea sporulation from the vine debris and debris degradation rate. Bait lamina probes, which measure soil biological activity, were placed in the soil-mulch interface three weeks before each of the two bag-recovery dates in both years and were then removed and assessed at the same times as were the bags. All mulches led to a reduction in B. cinerea sporulation. This reduction was significantly correlated with elevated rates of vine debris decomposition and increased soil biological activity. Over both years, compared with the controls, all treatments gave a 3-20-fold reduction in B. cinerea sporulation, a 1.6-2.6-fold increase in vine debris degradation and in the two marc and the paper treatments, a 1.8-4-fold increase in activity of soil organisms. The mulches also altered vine characteristics and elevated their resistance to B. cinerea through changes to the soil environment. Functional soil biological activity, as measured by Biolog Ecoplates and bait lamina probes, was increased 2-4 times in the two marc and paper treatments, compared with the control, an effect relating to the elevated soil moisture and reduced temperature fluctuations under these mulches. Soil nutrient levels and the C:N ratios were also affected in these treatments. The mulched paper lowered vine canopy density by up to 1.4 times that of the other treatments, an effect which probably led to elevated light penetration into the canopy and consequent increased canopy temperature, photosynthesis and lowered canopy humidity. These changes to soil and vine characteristics increased grape skin strength by up to 10% in the paper treatment and sugar concentrations by 1.2-1.4 °Brix in the two marc and paper treatments. The severity of B. cinerea infections in the anaerobic marc, aerobic marc and paper treatments were reduced to 12%, 3% and 2.2% of the control, respectively, in field assessments averaged over two consecutive harvests. Cover crops mulched in situ had similar effects to those of the organic mulches, increasing soil biological activity and reducing B. cinerea primary inoculum and the severity of B. cinerea infection in grapes at harvest (2006). Inter-row phacelia and ryegrass were mulched in winter 2005 and compared with a bare ground control, under 10-year-old Chardonnay vines in a ten-replicate randomized block design. Functional soil biological activity increased by 1.5-4.5 times in the two cover crop treatments compared with the control, an effect possibly related to elevated soil moisture in these treatments. This increase in soil moisture and soil biological activity increased vine debris degradation, reduced B. cinerea primary inoculum on the debris and decreased B. cinerea severity at flowering (December 2005) and harvest (April 2006). These results show the potential of organic mulches and cover crops mulched in situ to enhance soil ecosystem services and improve the sustainability of viticultural practices.
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7

Shan, Jia-Ching, and 沈佳慶. "Hillside soil and water conservation action information management system established research." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/zg2gfq.

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碩士
中華大學
營建管理學系碩士班
101
The Soil and Water Conservation Law was legislated and announced on July 25, 1994. This is the final accomplishment for 20years from industry, government and academic teams. The formulating of this law can be regarded as the most important source of soil and water conservation for hillside project. The objectives of the legislation is to protect Taiwan's water conservation, water and land resources, and relief water and soil disaster. It is an important law to assure the safe living environment and enjoy life for Taiwan citizens. With the popularization of the smart phone and wireless network, the APP software was used world-wide. Variety of application software makes much convenit than old generation in human life. The smart phone does change user's habits. In the past, user needed to use the computer connected to the internet to obtain information such as weather forecasts, and traffic route planning. After the available of smart phones, it can be used to fetch life information and make a convinient life. ER Model, SQL Server, Super Pad and Smart Phone are used in this study to develop "Mobile Water and Soil Conservation Information System for Hill side". The system integrates Hillside data, Land Usage, Ownership division, Land Ownership, and Engineering Inspection Operations. Soil and water conservation staffs can use smart-phones in the outdoor survey through wireless network to update geology, soil, major road systems, land usage, engineering distribution, location, and hillside related data at the first time. This can significantly reduce human error, improve the timeliness and accuracy of the information, provide a powerful management tool for soil and water conservation projects.
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8

HSU, HUNG-TA, and 許宏達. "The Juristic Research of the Inspection Trust Systems in Soil and Water Conservation Plan." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/bx226k.

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9

Tsai, Jian-Tze, and 蔡建澤. "Complete face of soil and water conservation concrete surface state analysis and inspection standards research." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/41924717354487659740.

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碩士
逢甲大學
土木工程所
99
This research is based on the complete face of concrete surface executed by Soil and Water Conservation Bureau, Council of Agriculture, Executive Yuan in these years. Process the on-site investigation and check the construction quality by the common defects and causes of the sorted record classification. The defects evaluation data is the basis of complete face of concrete surface levels and which are separated into severe, medium and mild levels. Review the causes, analyze and compare the results of the complete face of concrete surface defect samplings with the “Regulations of Soil and Water Conservation Concrete Construction” to propose the effective process procedure in advance for controlling and to research the regulations of surface repairing. Review, analyze and compare the complete face of concrete surface defect samplings to check the engineering execution situation then figure out the optimal process procedure and the best beneficial results. Prevent the same defects occur in the following up execution engineering concrete complete surface. This research could be the reference of arrangement to the similar issue and could upgrade the concrete construction quality. Also, this research could be the check standard of engineering quality. Wish this research could assist and benefit the future engineering quality.
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10

Wu, Yan-Ling, and 吳延陵. "The Research on the Participation Motivation, Organizational Commitment, and Job Satisfaction of Soil and Water Conservation Volunteers." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/59002256599389574983.

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碩士
國立中興大學
水土保持學系所
105
To improve the understanding of knowledge of soil and water conservation, the Soil and Water Conservation Bureau established the first outdoor classroom as a site for promotion and propaganda in 1989. The volunteers were recruited to help the educational propaganda in 1991. The training programs were then held to make the transformation of volunteers because of the Volunteer Service Act promulgated in 2001. Therefore, the study selected the soil and water conservation volunteers as the research object. The objective of this study was to understand the difficulties and needs of soil and water conservation volunteers during the services. The participation motivation, organizational commitment and job satisfaction was investigated by the questionnaire survey. The results were expected to be used as a basis for volunteer training and management. The data of questionnaire were analyzed by IBM SPSS Statistics 21. The results showed that the backgrounds of soil and water conservation volunteers were in high homogeneity. There were not many difficulties encountered during the services. However, the demands in professional training programs were high. The main participated motivations were serving others and self-achievement. The organizational commitment and job satisfaction were shown to be satisfied. However, the volunteers with low monthly income and high seniority showed significant differences in the participated motivation, organizational commitment and job satisfaction. The Pearson product-moment correlation was used to estimate the correlation. The correlation coefficient between the participated motivation and organizational commitment was 0.749. The correlation coefficient between the participation motivation and job satisfaction was 0.734. The correlation coefficient between the organizational commitment and job satisfaction was 0.776. The participated motivation, organizational commitment and job satisfaction were high-positive correlated.
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11

Chiu, Ting-Hsiang, and 邱鼎翔. "The research of Cure within a prescribed time limit and Imposing punishment successively pursuant in Soil and Water Conservation Act." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/08992171679801696685.

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碩士
國立中正大學
法律所
98
For the administrative control measure in our country, cure within a prescribed time limit frequently exists in the administrative law to exclude the illegal state. In order not to punish the past illegal acts of the author, cure within a prescribed time limit and the administrative order to punish are not the same. Based on the legal principle of punishment, cure within a prescribed time limit does not need to be strictly stipulated by law or legal order. If cure within a prescribed time limit has affected the rights and obligations of the people, in view of the interference retention principle, the legal retention principle is supposed to be applied. Since cure within a prescribed time limit is just the concrete of the prescribed law or legal order, it is worth discussing whether the legal retention principle should be suitable. In addition, not fulfilling of cure within a prescribed time limit, which is the calculating basis of imposing punishment successively pursuant, is the element in Soil and Water Conservation Act. Hence, imposing punishment successively pursuant has the punitive nature of not fulfilling of cure within a prescribed time limit. Judging from the purpose of imposing punishment successively pursuant, it is to supervise the author to complete the matters to be cured. So the purpose of imposing punishment successively pursuant is different from the administrative order to punish, which is to punish the author’s past behavior of violating the administrative order, but it is the same with the administrative execution continuously to punish, which causes the author to produce the compelling force at heart, then forcing the author to complete the correction duties as soon as possible. Moreover, because duties of cure within a prescribed time limit remain unchanged, imposing punishment successively on the identical correction duty violates the double jeopardy principle. Therefore, this article attempts to explore the natures of cure within a prescribed time limit and imposing punishment successively pursuant and further analyzes the legal retention principle of cure within a prescribed time limit and the law application question of imposing punishment successively pursuant in the framework of Soil and Water Conservation Act.
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12

Chen, Chung-Chih, and 陳重志. "The research of the thematic curriculum design and the learning effectiveness on soil and water conservation in the elementary school." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/78469525211493393463.

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碩士
國立屏東科技大學
水土保持系所
96
Water, soil and all of the creatures in the nature are precious resources on the earth . The resources in such a small island Taiwan are originally finite , the frequent occurrence of natural disasters in the past years, constant overexploitation of soil resources cause the devastating damage to the silva in the mountains. Therefore, the severe catastrophes befall us whenever typhoons, heavy rain and earthquakes happen. However, with no alternatives and after the complaints ,in addition to decreasing damage to the lowest extent and enhancing detection ,the reinforcement of promoting the notions of soil and water conservation is most important for the time being. In other words, to educate residents from their childhood to be aware of cherishing trees , water , soil resources and this place where they live. Hence , the purpose of the researches is to probe the teaching activities of soil and water conservation proceeded by means of the media of soil and water conservation thematic curriculum and ends up with tendering the analysis results of these activities. These researches will lead students to learn the fundamental concepts of soil and water conservation with seven chapters :“How beautiful the school campus is!”, ”The lovely green ground! ”Donuts of drawing and writing” “ Traveling with the water drop” “ The little hero of water conservation “ The big fight for saving environment”. And attain the learning objectives of environmental and soil and water education through students’ learning activities and observation. The results of the researches are as follows: 1. The correct answer rates of paper assessment of those classes in which soil and water conservation thematic activities are implemented are 85, 79 and 84 respectively, and the correct answer rate of the class which did not implement water-soil conservation thematic activities is 95.The teaching activities designed by media of soil and water conservation thematic teaching activities can reach effectively the teaching objectives. The students can have the responsibility of cherishing and protecting the environment in the condition of soil and water conservation thematic teaching activities. 2. According to Paired-Samples t test, the correlation between paired samples is 97.2, which has reached statistically significant. The students can obtain the concerning notions of soil and water conservation under the circumstances of soil and water conservation thematic teaching activities. 3. Paper assessments are conducted before and after the implementation of soil and water conservation thematic activities. The mean score of the pretest is 76.12, and the mean score of the posttest is 95.64. The means of the achievements of pretest and posttest are significant different, and the posttest has better result. The soil and water conservation thematic teaching activities have remarkable elevation for the learning of students’ environmental education and connecting with living experience. Soil and water conservation thematic teaching activities have the functions of attracting students’ attention, helping construct the environmental concepts , expanding the living experience , bringing imagination to full play and cultivating the observation. Thus , the use of soil and water conservation thematic teaching activities to improve the sentiments of environmental education and promotion of soil and water conservation education is a feasible way .
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13

Li, Meng-hsun, and 李孟勳. "Research on Administration Penalty Act and Soil and Water Conservation Law-based on Article 18 and Article 21 of the Administration Penalty Act." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/33396571591421206772.

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14

Calvert, Darren Rhett. "An investigation of rainfall characteristics, erosivity and soil erosion on Round Island, Mauritius." Diss., 2017. http://hdl.handle.net/10500/23593.

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Round Island is a small (208 ha) islet of volcanic origin located 22.5 km north east of mainland Mauritius and has been classified as a nature reserve since 1957. Two sites were chosen for the installation of environmental monitoring equipment. A series of Gerlach troughs were installed to capture surface sediment transported by runoff, which were used to document sediment yields and determine the particle size distribution. Overall, rainfall and erosivity on Round Island is far less, when compared to mainland Mauritius. However, erosivity from Round Island (2,314.76 MJ.mm.ha-1.h-1.yr-1) is slightly above the global average of 2,190 MJ.mm.ha-1.h-1.yr-1. In terms of sediment transport, the annual sediment movement rates for Round Island were established during this study (0.1248 t.ha-1.yr-1) and were found to be considerably lower than Mauritius (10 t.ha-1.yr-1), as well as other tropical island such as Kauai (0.86 t.ha-1.yr-1) and O’ahu (0.6 t.ha-1.yr-1). Thus, although the estimated rates of soil erosion are very low for humid tropical regions, these rates only reflect the contemporary environmental conditions and cognisance of the landscape history should be incorporated into assessments of soil erosion
Geography
M. Sc. (Geography)
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15

Wall, Andrew James. "The effect of poplar stand density on hill country pastures : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy (PhD), Massey University, Palmerston North, New Zealand." 2006. http://hdl.handle.net/10179/1517.

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One-third of the North Island of New Zealand has been identified as requiring increased soil conservation if pastoral farming is to be sustainable. For over 50 years the planting of widely spaced poplar trees (Populus spp.) has been one of the main methods used to control soil erosion on hill pastures. Research has shown that these plantings have successfully decreased soil erosion but their impact on the productivity of pastoral farming has received little research attention. The research that has been undertaken has found poplars can suppress understorey pasture production by up to 40%, suggesting that farmers require more research information on the impact of planting conservation trees on the productivity of their farm if the use of conservation trees is to be more widely adopted on erosion prone land. The objective of this thesis was to provide comprehensive data on the relationship between the range of poplar densities used for soil conservation on the light and soil under poplars, and consequently the effect on understorey pastures. Three field sites on commercial sheep and beef hill farms, in regions with contrasting summer soil moisture availability, Manawatu (one site) and Central Hawke's Bay (two sites), were monitored for two years. Tree stocking rates ranged from 0 to 375 trees/ha. Measurements were based on units of four trees with most measurements either directly below the tree crowns or in the gaps between the trees, but more intensive transect measurements were also made. Photosynthetically active radiation (PAR) and the ratio of red to far red light (R:FR) were measured under the trees and in open pasture controls. Stand density indices used included all the commonly used measures of tree canopies, including digital photography, and stem diameter at breast height (DBH). PAR transmission was inversely related to all of the stand density indices with canopy closure based on digital photographs being the most robust of the indices used. PAR under the trees, relative to open pasture, was greater in the gaps than below tree crowns. Under a completely closed canopy, PAR transmission was reduced to 15-20% and 50-55% of the open pasture in summer and winter, respectively. The RFR under the trees, relative to open pasture, decreased markedly at high stand densities (allowing less than 40% PAR transmission) in summer, but was similar in winter. The change in PAR under the trees was shown to be a major factor limiting pasture growth, particularly directly below the tree crowns. For both summer and winter, canopy closure measured with a standard digital camera was strongly related to stand level PAR transmission (r2=0.88-0.97; P<0.0001) and was also a practical method of measuring canopy closure in the field. The soil measurements confirmed earlier research that soil pH increases under mature poplar trees. There was a 0.2 - 0.7 unit increase in soil pH in the upper 75 mm of soil over both contrasting regions. The soil fertility under the trees in terms of requirements for pasture growth was similar to that of the open pasture with calcium and potassium up to 2.2 and 9.0 quick test units higher in the soil under the trees than in the open pasture, respectively. The direct cause of the increased concentration of some cations under the trees was the annual tree leaf litter. Overall, the soil fertility under the trees had the potential to produce similar pasture production to that of the open pasture with the added advantage of less acid conditions. Averaged over all sites the respective annual net herbage accumulation (ANHA) under poplar canopy closures of 25, 50 and 75 % was estimated from the equations developed to be 77, 60 and 48% of the open pasture. The greatest decrease was directly below the tree crowns where at canopy closures greater than 20% the ANHA was a relatively constant 50% of open pasture. In the vertically projected gap between trees the ANHA decreased by 6.6% relative to open pasture for each 10% increase in canopy closure. At approximately 80% canopy closure there was no difference between the ANHA directly below the trees and in the gap. Pasture net herbage accumulation (NHA) under the trees relative to open pasture was at its lowest in summer and autumn (36% of open pasture under a closed canopy), and at its greatest in early spring before tree canopy leafed out (72% of open pasture under a closed canopy). The botanical composition and feed value of the pasture under the trees was broadly similar to that of the open pasture. The greatest impact of the poplars on the pasture was decreased NHA due to shading. The decrease in NHA directly below mature unpruned poplars is substantial and would decrease farm profitability if the poplar stand density were high over a large area of the farm. The use of poplars for soil conservation is essential but these results show the importance of managing trees through pruning and thinning so that canopy closure is minimised. ANHA under the trees can be maintained at 75% of the open pasture if canopy closure is prevented from exceeding 30-40%.
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16

Uys, Charmaine Janet. "Invertebrate diversity in afrotemperate forests : spatial and seasonal changes and implications for conservation." Thesis, 2006. http://hdl.handle.net/10413/3165.

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Forests in the Drakensberg Mountains, although generally small and fragmented, represent a wealth of globally significant biodiversity. This is especially true of the invertebrate fauna, which includes a range of localized endemic species. Ground dwelling, flightless invertebrates living in forests show relative immobility and poor dispersal abilities compared to birds, butterflies and other animal taxa. The naturally fragmented state of Afrotemperate forests also geographically isolates these taxa. No quantified, systematic surveys of flightless invertebrates have been conducted in Afrotemperate forests in the Drakensberg Mountains. This means that, to date, invertebrates have not been considered in the management of these habitats. However, invertebrates are vitally important in ecosystem functioning and maintenance and must be included in management plans. This study quantified flightless invertebrate diversity in Afrotemperate forest patches in the Drakensberg by investigating spatial patterns and seasonal changes in invertebrate diversity. The broad objectives were to: 1) Determine the appropriate spatial scale at which conservation of flightless invertebrates should be implemented; 2) Determine which season, taxa and sampling methods are most suitable for biodiversity assessment and monitoring in Afrotemperate forest; and 3) Investigate methods of prioritizing Afrotemperate forests for conservation of flightless invertebrate diversity. Seventeen forest patches in six valleys in four Drakensberg reserves (Rugged Glen Nature Reserve, Royal Natal National Park, Cathedral Peak and Injisuthi) were sampled in the summer of 2004/2005. In addition, three forests at Injisuthi were sampled in March, June, September and December 2004 to enable seasonal comparisons. Sampling methods included soil samples, leaf litter samples, pitfall traps, active search quadrats and tree beats. The study focused on terrestrial molluscs (Class Gastropoda), earthworms (Class Annelida), onychophorans (Class Onychophora), centipedes (Class Chilopoda), millipedes (Class Diplopoda) and ants (Class Insecta). Target taxa were sorted to morphospecies and then identified to species by taxonomic experts. Seventy-two species and a total of 5261 individual specimens from the six target taxa were collected. Species composition of sites varied along the north-south gradient, and species turnover (beta diversity) was related to the distance between sites. Flightless invertebrate species richness and community structure fluctuated seasonally. Therefore, I recommend that sampling should take place during the wet season (summer months). Molluscs were the most suitable taxon among those surveyed to represent flightless invertebrate diversity and leaf litter samples and active search quadrats are the most suitable sampling methods for flightless invertebrates in forest. This study compared approaches to prioritizing Afrotemperate forests in terms of their invertebrate diversity using ranked species richness with complementarity indices of species presence/absence, taxonomic distinctness (orders, families and genera) and endemicity. There was no consistent spatial trend in the priority ranking of forests based on species richness. Complementarity based on species richness only required eight out of 17 forests to represent all 62 species. Although complementarity based on taxonomic distinctness and endemicity required fewer sites, not all species were represented. The minimum set of sites identified using complementarity based on species richness and augmented with information on taxa of conservation importance (local endemic and threatened species) was the most rigorous approach to prioritizing Afrotemperate forest patches in the Drakensberg for flightless invertebrate conservation. Urgent conservation interventions are required because invertebrates play a critical role in ecosystem functioning. As many forest patches and invertebrate populations as possible should be protected to conserve the full complement of invertebrate species of the region. Special management attention should be paid to the eight forests identified as priority sites in the complementarity analyses. Forest patches cannot survive in isolation, so it is important to manage the grassland, riverine vegetation, forest ecotone and forests holistically. Provisional targets were set for the conservation of flightless invertebrates, based on estimates of the requirements for persistence of invertebrates in Afrotemperate forest, made within the constraints of available information and expert opinion.
Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
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17

Tyslová, Radka. "Protierozní opatření na orné půdě ve vnímání zemědělců." Master's thesis, 2018. http://www.nusl.cz/ntk/nusl-372906.

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(in english): Modern agriculture faces soil erosion as one of its problems in the Czech Republic. Soil conservation practices are implemented to prevent erosion. This thesis reports on perception of the soil conservation practices by farmers themselves. Hypothesis of the research is based on declaration of organic farming in the Czech Republic: to specifically protect natural sources. Main research question is: Is there a difference in perception of soil conservation practices between certified organic farmers and farmers using conventional methods? As a concept to examine perception, this thesis uses the theory of planned behavior developed by Icek Ajzen. Results show that farmers' attitudes towards soil conservation practices in general are negative. Their attitudes can be explained by intermingling beliefs about erosion, the agriculture subsidy system and own soil quality. Specific practices are evaluated by other than anti-erosion effects. The farmers do not perceive social pressure from their peers to adopt soil conservation practices and their perceived control over adoption of a practice is low. Evaluating the level of difficulty of specific practices, smaller farmers feel substantial difficulties regarding financial issues. The results do not indicate a difference in perception of soil...
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18

Prajapati, Prajaya. "Biological potential and diffusion limitation of methane oxidation in no-till soils." Thesis, 2014. http://hdl.handle.net/1805/4446.

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Indiana University-Purdue University Indianapolis (IUPUI)
Long term no-till (NT) farming can improve the CH4 oxidation capacity of agricultural lands through creation of a favorable soil environment for methanotrophs and diffusive gas transport. However, limited data is available to evaluate the merit of that contention. Although the potential for biological CH4 oxidation may exist in NT soils, restricted diffusion could limit expression of that potential in fine-textured soils. A study was conducted to assess the CH4 oxidation potential and gaseous diffusivity of soils under plow till (PT) and NT for > 50 years. Intact cores and composite soils samples (0-10 and 10-20 cm) were collected from NT and PT plots located at a well-drained site (Wooster silt loam) and at a poorly-drained (Crosby silt loam) site in Ohio. Adjacent deciduous forest soils were also sampled to determine maximum rate expected in undisturbed soils in the region. Regardless of study sites and soil depth, CH4 oxidation rate (measured at near ambient CH4) and oxidation potential (Vmax, measured at elevated CH4) were 3-4 and 1.5 times higher in NT than in PT soils, respectively. Activity in the NT soils approached (66-80 %) that in the forest soils. Half saturation constants (Km) and threshold for CH4 oxidation (Th) were lower in NT (Km: 100.5 µL CH4 L-1; Th: 0.5 µL CH4 L-1) than in PT soils (Km: 134 µL CH4 L-1; Th: 2.8 µL CH4 L-1) suggesting a greater affinity of long-term NT soils for CH4, and a possible shift in methanotrophic community composition. CH4 oxidation rates were lower in intact soil cores compared to sieved soils, suggesting that CH4 oxidation was limited by diffusion, a factor that could lead to lower field-measured CH4 uptake than suggested by biological oxidation capacity measured in the laboratory. Regardless of soil drainage characteristic, long-term NT resulted in significantly higher (2-3 times) CH4 diffusivity (mean: 2.5 x 10-3 cm2 s-1) than PT (1.5 x 10-3 cm2 s-1), probably due to improved soil aggregation and greater macro-pores volume in NT soils. Overall, these results confirm the positive impact of NT on the restoration of the biological (Vmax, Km and Th) and physical (diffusivity) soil attributes essential for CH4 uptake in croplands. Long-term implementation of NT farming can therefore contribute to the mitigation of CH4 emission from agriculture.
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19

Hussain, Zaker. "Environmental effects of densely planted willow and poplar in a silvopastoral system : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Ph. D.) in Agroforestry, Institute of Natural Resources, Massey University, Palmerston North, New Zealand." 2007. http://hdl.handle.net/10179/1405.

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New Zealand, having large areas of hilly landscapes, is subject to the risk of soil erosion, and summer and autumn droughts that limit pasture growth, which in turn affects the livestock-based economy. The nitrogen and phosphorus input in fertilisers coupled with livestock excreta and soil disturbance impose a serious threat to downstream water quality. The planting of trees is one option used to decrease soil erosion, increase the quantity of forage and manage runoff. To date, research has mainly focused on wide spaced poplar trees for feed quality and their effects on understorey pasture growth. However, there is increasing interest in the use of densely planted willow and poplar for fodder purpose. The effects of young (< 5 yrs old) willow and poplar planted at close spacing on runoff, soil erosion, growth of understory pasture and nutrient losses have never been studied in New Zealand. Three field trials (two at Crop and Research Unit, Moginie, Manawatu and one at Riverside Farm, Masterton) were conducted between October 2004 and November 2006 that incorporated comparative establishment and growth of densely planted willow and poplar and their effects on soil moisture, runoff, sediment load and nutrient losses from grazed and fertilised farmland. It was concluded that densely planted willow and poplar (3-4 yrs) reduced total nitrogen (TN) and dissolved reactive phosphorus (DRP) by 47 % each and sediment load by 52 %. Young trees reduced surface runoff and soil moisture more as they aged. However, due to their deciduous nature willow and poplar were not effective in reducing surface runoff in winter and early spring. Sheep preferred camping under trees, especially in late spring and summer, and this led to greater deposition of dung and urine under trees than open pasture. Sheep grazing, especially in winter, significantly increased sediment and nutrient loads in runoff water. The N and P fertiliser application increased nutrient load in runoff water well above the threshold level required to initiate algal growth to create eutrophication. Densely planted willow and poplar significantly reduced understorey pasture growth by 23 % and 9 %, respectively, in their second year at Moginie, mainly due to shade, but coupled with soil moisture deficit in summer. The pasture growth in a willow browse block was 52 % of that in open pasture as a result of shade and differences in pasture species composition. Sheep browsing reduced willow leaf area significantly. Willow and poplar survival rates were similar (P > 0.05) after two years of establishment (100 % vs 90.5 %, respectively). However, willow grew faster than poplar in height (1.90 vs 1.35 m), stem diameter (43.5 vs 32.6 mm), canopy diameter (69 vs 34 cm) and number of shoots (8.7 vs 2.3) at the age of two years, respectively. The research clearly demonstrated that densely planted young willow and poplar trees can reduce runoff, sediment load and nutrient losses from farmland to freshwater, but shade and soil moisture can limit pasture growth under trees. It is recommended that willow and poplar should be planted at wide spacing on the whole farm to minimise loss of pasture. Where blocks of trees are necessary, such as willow browse blocks, sheep browsing can be used as a tool to reduce shade to improve pasture growth. Livestock access to riparian strips should be minimal to avoid livestock camping that can have deleterious effects on water quality.
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