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Literatura académica sobre el tema "Nutrients spatial variability"

Autor: Grafiati

Publicado: 10 de marzo de 2023

Última modificación: 11 de marzo de 2023

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Artículos de revistas sobre el tema "Nutrients spatial variability"

1

Zhao, Gengxing, Chao Dong, Xiaona Chen, and Baowei Su. "Scale Characteristics and Effects on Spatial Variability of Soil Available Nutrients." Applied Engineering in Agriculture 35, no. 2 (2019): 221–30. http://dx.doi.org/10.13031/aea.12963.

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Abstract.The spatial variability of farmland soil nutrients on different scales is important for farming as it forms the basis for the efficient utilization of soil nutrients and precision fertilization. Survey points were distributed throughout the study area on three different scales (county, field, and block). Research on the scale effect of the spatial variability of available nitrogen (AN), available phosphorus (AP), and available potassium (AK) involved a combination of classical statistics, geostatistics, and Geographic Information System (GIS) techniques. Results indicated that the thr

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2

Qin, Zi Han. "Research on the Spatial Variability of Soil Nutrients Prediction Based on GIS." Advanced Materials Research 791-793 (September 2013): 1681–85. http://dx.doi.org/10.4028/www.scientific.net/amr.791-793.1681.

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Soil is a necessary nutrition library of crop growth, its nutrient spatial variability exists the whole crop growth period with the characteristics of long and complex, so the spatial variability of soil nutrient prediction is one of the hot research problems to be urgently solved in precision agriculture. This paper first introduces GIS and statistical analysis organic combination of research method and model, on the basis of this, based on GIS spatial data level of analysis and point-line-side buffer, we will accurate analysis of point-line-sides mutation interval through the variation Eucli

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Zhao, Yue Ling, Hai Yan Han, Li Ying Cao, and Gui Fen Chen. "The Nutrients Spatial Variability of Black Soil Based on GIS." Applied Mechanics and Materials 694 (November 2014): 580–83. http://dx.doi.org/10.4028/www.scientific.net/amm.694.580.

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The precision agriculture (PA) is the end product of the modern high tech's information technology and the agricultural production technology union. The soil nutrients are not only an important component of soil research, but also a critical determinant of its productivity. Some soil nutrients spatial distribution pictures were established based on important factors that affect crops production. The soil nutrient situation was understood by the paper in Jilin province black soil. The results can realized some information opening and sharing and helped some farmer and manager to understand some

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4

Long, Linli, Ying Liu, Xiaoyang Chen, et al. "Analysis of Spatial Variability and Influencing Factors of Soil Nutrients in Western China: A Case Study of the Daliuta Mining Area." Sustainability 14, no. 5 (2022): 2793. http://dx.doi.org/10.3390/su14052793.

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An understanding of the spatial variation and influence factors of soil nutrients in mining areas can provide a reference for land reclamation and ecological restoration. Daliuta was used as the study area. The spatial variability of soil nutrients was analyzed using traditional statistics and geostatistics. The effects of topography, mining history, and soil erosion were discussed. The results indicate that the soil pH of the Daliuta mining area is slightly acidic to slightly alkaline, and the soil organic matter, available nitrogen, available phosphorus, and available potassium belonged to t

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5

Carr, Geneviève M., Patricia A. Chambers, and Antoine Morin. "Periphyton, water quality, and land use at multiple spatial scales in Alberta rivers." Canadian Journal of Fisheries and Aquatic Sciences 62, no. 6 (2005): 1309–19. http://dx.doi.org/10.1139/f05-044.

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The ability of land use to replace water quality variables in predictive models of periphyton chlorophyll a was tested with a 21-year data set for Alberta rivers. Nutrients (total dissolved P and NO2 + NO3) explained 23%24% of the variability in seasonal chlorophyll a, whereas land use (human population density) explained 25%28% of the variability. The best models included the combination of total dissolved P and population density, explaining 32%34% of periphyton chlorophyll a variability. However, analysis of variance of chlorophyll a by ecoregions and ecozones explained about as much var

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Behera, S. K., K. Suresh, K. Ramachandrudu, K. Manorama, and B. N. Rao. "Mapping spatial variability of leaf nutrient status of oil palm (Elaeis guineensis Jacq.) plantations in India." Crop and Pasture Science 67, no. 1 (2016): 109. http://dx.doi.org/10.1071/cp15029.

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Spatial variability of leaf nutrients in oil palm (Elaeis guineensis Jacq.) plantations in Goa, Karnataka, Mizoram and Gujarat states of India were examined for implementation of site-specific fertilisation programs. Georeferenced leaf samples were collected randomly for the oil palm plantations. The leaf nutrient concentrations were assessed and analysed statistically and geostatistically. The concentrations of leaf nutrients such as nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S) and boron (B) in oil palm plantations varied widely at different locations.

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7

Kumar, Hemendra, Puneet Srivastava, Jasmeet Lamba, et al. "Within-Field Variability in Nutrients for Site-Specific Agricultural Management in Irrigated Cornfield." Journal of the ASABE 65, no. 4 (2022): 865–80. http://dx.doi.org/10.13031/ja.15042.

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HighlightsPhosphorus and nitrogen in soil and plants varied during the growing season across the cornfield.Spatial variability in nutrients caused spatial variability in plant growth and crop yield across the cornfield.Hydrological characteristics and soil hydraulic properties were responsible for spatial variability in nutrients.Need to consider spatial variability in nutrients in delineating management zones before adopting management practices.Abstract. The adoption of precision agricultural practices in Alabama has been increasing in recent years. Although challenging, understanding nutrie

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8

Siswanto, Eko, MD Latifur Rahman Sarker, and Benny N. Peter. "Spatial variability of nutrient sources determining phytoplankton Chlorophyll-a concentrations in the Bay of Bengal." APN Science Bulletin 2022, no. 1 (2022): 56–64. http://dx.doi.org/10.30852/sb.2022.1834.

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Primary production is a key marine ecosystem driver in the Bay of Bengal and is important for the societies and economies of the surrounding countries. Although the availability of inorganic nutrients is known to control primary production in this region, the specific nutrient sources that affect primary production in different parts of the bay have not been identified. In this study, we assess the importance of nutrients from different sources in determining chlorophyll-a concentration, an indicator of primary production, in the Bay of Bengal by conducting multiple linear regression of satell

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Neatrour, Matthew A., Robert H. Jones, and Stephen W. Golladay. "Correlations between soil nutrient availability and fine-root biomass at two spatial scales in forested wetlands with contrasting hydrological regimes." Canadian Journal of Forest Research 35, no. 12 (2005): 2934–41. http://dx.doi.org/10.1139/x05-217.

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We investigated the relationship between soil nutrients and fine-root biomass at broad (among ecosystem types) and fine (within a 20 m × 20 m plot) spatial scales in forested wetlands of the southeastern United States. We selected three replicates each of high-fertility floodplain swamps, low-fertility depressional swamps, and intermediate-fertility river swamp sloughs and measured soil nutrient availability (NO3-N, NH4-N, and PO4-P) and fine-root biomass. At one replicate of each wetland type, a dense network of sampling points was used to measure variability (variance and coefficient of vari

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10

Kambale, J. B., and H. V. Rudramurthy. "Application of Geographical Information System to Understand Spatial Variability of Soil Available Nutrients in Northern Karnataka, India." Current World Environment 12, no. 1 (2017): 169–73. http://dx.doi.org/10.12944/cwe.12.1.20.

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It is very important to distinguish the spatial variability in soil fertility for site specific nutrient application. To know the status, 25 soil samples were collected from Vandurga Village, Yadgir District, Karnataka, India. Samples were analysed for electrical conductivity (EC), power of hydrogen (pH), organic carbon (OC), Nitrogen (N), Phosphorous (P2O5) and Potassium (K2O). Further, SPSS (ver. 19) was used to execute conventional statistical analysis and ArcGIS to get the information about distribution and spatial variability of soil available nutrients. The analysis results showed that t

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Tesis sobre el tema "Nutrients spatial variability"

1

Dias, Jos? Eduardo. "Monitoramento do uso da terra e dos n?veis de nutrientes do solo no Sistema Integrado de Produ??o Agroecol?gica utilizando geoprocessamento." Universidade Federal Rural do Rio de Janeiro, 2007. https://tede.ufrrj.br/jspui/handle/tede/549.

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Made available in DSpace on 2016-04-28T14:58:59Z (GMT). No. of bitstreams: 1 2007- Jose Eduardo Dias.pdf: 7576584 bytes, checksum: f462c307c38711b0d35ca1237ce04396 (MD5) Previous issue date: 2007-05-18<br>Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico<br>Agroecological production systems are more complex than conventional ones, since a series of crops follow in sequence or are intercropped to achieve high diversity and maximize soil nutrient recycling. The full understanding of these systems require systemic analyses and therefore, adequate tools. To understand soil fertilit

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2

Smucker, Nathan J. "Using Diatoms and Biofilms to Assess Agricultural and Coal Mining Impacts on Streams, Spatio-Temporal Variability, and Successional Processes." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1276285170.

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Malecki, Lynette. "Temporal and spatial variability of nutrient fluxes from sediment in the lower St. Johns River." [Gainesville, Fla.]: University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000568.

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4

Oelsner, Gretchen Pauline. "Spatial and Temporal Hydrologic Variability as a Control on the Nutrient Dynamics of the Upper Rio Grande." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194215.

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Large rivers in semiarid regions provide valuable resources for municipalities, agriculture, and adjacent ecosystems, yet the limited nature of the resource requires a concerted effort to understand the controls on water quality. To address this issue I continued and adapted biannual geochemical synoptic sampling of the Rio Grande from Del Norte, CO to Elephant Butte Reservoir between August 2003 and 2006 which had started in 2001. During average to drought conditions, river discharge was derived primarily from snowmelt in the headwaters region, total dissolved solutes increased downstream,

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5

Fernández-Martínez, Marcos. "On the role of nutrients, climate and anthropogenic impacts in spatio-temporal variability of forest productivity." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/385914.

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Els boscos són dels ecosistemes terrestres més importants en termes de fotosíntesi i segrest de carboni, perquè n’acumulen i en segresten en grans quantitats, com a biomassa i com a matèria orgànica del sòl. A més, els boscos proporcionen polsos de recursos, a traves de la producció de fruits, que poden comportar efectes en cascada a través de la xarxa tròfica de l’ecosistema. L’objectiu d’aquesta tesi és caracteritzar l’estructura i el funcionament dels boscos i quantificar llurs productivitats ecosistèmiques. La nostra recerca s’ha centrat en entendre els controls del balanç de carboni i de

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6

Klasner, Laura M., and Laura M. Klasner. "The influence of spatial and temporal hydrologic variability on nutrient fluxes and transformations, San Pedro River, Arizona, USA." Thesis, The University of Arizona, 2006. http://hdl.handle.net/10150/626916.

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Pre-monsoon (June) and monsoon (August) sampling campaigns were conducted on a gaining and a losing reach in the San Pedro River in 2005 to quantify the effects of variability in hydrologic conditions on carbon and nitrogen cycling in an N-limited semi arid stream. Nutrient concentrations decrease along the gaining reach, while new groundwater inputs, rapid N03-N uptake and net production of organic DOC and DON occurs. In contrast, the losing reach experiences little spatial variability suggesting the presence of a large, well-mixed alluvial aquifer as a single source. However, so/

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7

Montiel, Luis Ramiro Samaniego. "Balanço e evolução temporal de teores de fósforo e potássio no solo em áreas manejadas com agricultura de precisão." Universidade Federal de Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/5540.

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The need for improving nutrient use efficiency and increase savings demand a better knowledge of soils and production systems. The objective of this study was to evaluate the soil P and K budget and its relationships with their temporal evolution on site-specific management areas. The experiments were carried out in four cropland areas from the Medium Plateau region of the Rio Grande do Sul state, located at the cities of Almirante Tamandaré do Sul, Tio Hugo, Não-Me-Toque and Vitor Graeff. Soil tests were used to verify the spatial variability, budget and temporal evolution of soil P and K lev

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8

Nogueira, Rafaella da Silva. "DistribuiÃÃo espacial de carbono, nutrientes e solo em Luvissolos sob sistemas agrÃcolas tradicionais e agroflorestais no municÃpio de Sobral-CE." Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=3335.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>O objetivo desse estudo foi avaliar os teores e estoques de carbono orgÃnico nas formas: total (COT), particulada (COP), associada (COA) e solÃvel em Ãgua (CSA), P disponÃvel, K e Na trocÃveis, assim como a possÃvel redistribuiÃÃo destes elementos e das partÃculas do solo pela erosÃo hÃdrica em sistemas agroflorestais, comparativamente ao sistema de cultivo tradicional e intensivo. O estudo foi desenvolvido em Ãrea experimental localizada na Fazenda Crioula, pertencente ao Centro Nacional de Pesquisa de Caprinos da EMBRAPA, no mu

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9

Causse, Jean. "Temporalité des transferts de nutriments dans les bassins versants à algues vertes." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1B012/document.

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En Bretagne, les « marées vertes » sont récurrentes depuis le début des années 70 et occupent une place importante dans le débat public en terme sanitaire, politique et économique. Lors de cette thèse, une large revue bibliographique a été réalisée sur l’export d’azote et une méthodologie innovante a été mise en place afin d’étudier la variabilité spatio-temporelle de l’export de nutriments dans 2 bassins versants à algues vertes à une échelle intra-annuelle et pendant des évènements extrêmes (évènements pluvieux, période touristique de basses eaux,…). Les bassins versants sélectionnés pour le

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10

Lee, Alyce R. "Response of Benthic Microalgal Community Composition at East Beach, Galveston Bay, Texas to Changes in Salinity and Nutrients." 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-625.

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Benthic microalgal community composition on an ephemerally submerged sandflat at East Beach, Galveston Island, Texas was studied to determine the spatial and temporal variability of total biomass and community composition and its responses to experimental manipulations of two environmental factors (salinity and nutrients). Four field studies were conducted between August 2004 and February 2005. The community consisted of two major algal groups, diatoms, and cyanobacteria with two less abundant groups, green algae, and phototrophic bacteria. Spatial variability showed that patch sizes of 12 - 2

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Libros sobre el tema "Nutrients spatial variability"

1

Rinella, Frank A. Seasonal and spatial variability of nutrients and pesticides in streams of the Willamette Basin, Oregon, 1993-95. U.S. Dept. of the Interior, U.S. Geological Survey, 1998.

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Rinella, Frank A. Seasonal and spatial variability of nutrients and pesticides in streams of the Willamette Basin, Oregon, 1993-95. U.S. Dept. of the Interior, U.S. Geological Survey, 1998.

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Rinella, Frank A. Seasonal and spatial variability of nutrients and pesticides in streams of the Willamette Basin, Oregon, 1993-95. U.S. Dept. of the Interior, U.S. Geological Survey, 1998.

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4

Maluk, Terry L. Spatial and seasonal variability of nutrients, pesticides, bacteria, and suspended sediment in the Santee River Basin and coastal drainages, North and South Carolina, 1995-97. U.S. Dept. of the Interior, U.S. Geological Survey, 2000.

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5

Debrewer, Linda M. Factors affecting spatial and temporal variability in nutrient and pesticide concentrations in the Surficial Aquifer and the Delmarva Peninsula. U.S. Dept. of the Interior, U.S. Geological Survey, 2007.

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Akana, Palani Robert. Patterns, mechanisms, and implications of spatial variability in the ecological processes regulating nutrient access by forest trees. [publisher not identified], 2022.

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Jacobsen, Dean, and Olivier Dangles. Living conditions in high altitude waters. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198736868.003.0003.

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Chapter 3 deals with the abiotic environment in high altitude lakes and streams worldwide. It searches for general patterns in relation to altitude, without overlooking the enormous variability, both temporally as well as at small and large spatial scales. Overall, environmental conditions in high altitude waters may be regarded as harsh. Indeed, certain features such as low temperature, low oxygen pressure, and high ultraviolet radiation (all a direct result of high altitude) as well as transparent and ion-poor waters with low nutrient concentrations are typical of high altitude aquatic syste

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Capítulos de libros sobre el tema "Nutrients spatial variability"

1

Zhao, Yueling, Haiyan Han, Liying Cao, and Guifen Chen. "Study on Soil Nutrients Spatial Variability in Yushu City." In Computer and Computing Technologies in Agriculture V. Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-27278-3_1.

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Cui, Bei, Wude Yang, Meichen Feng, Wenjiang Huang, and Xiaoyu Song. "Study on the Spatial – Temporal Variability of Soil Nutrients during Winter Wheat Growth Season." In Computer and Computing Technologies in Agriculture VI. Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-36137-1_29.

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Nolin, M. C., S. P. Guertin, and C. Wang. "Within-Field Spatial Variability of Soil Nutrients and Corn Yield in a Montreal Lowlands Clay Soil." In Proceedings of the Third International Conference on Precision Agriculture. American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, 2015. http://dx.doi.org/10.2134/1996.precisionagproc3.c26.

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Weber, L. H., and S. Z. El-Sayed. "Spatial Variability of Phytoplankton and the Distribution and Abundance of Krill in the Indian Sector of the Southern Ocean." In Antarctic Nutrient Cycles and Food Webs. Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-82275-9_41.

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Bannister, Jacob M., Ellen R. Herbert, and Christopher B. Craft. "Spatial Variability in Sedimentation, Carbon Sequestration, and Nutrient Accumulation in an Alluvial Floodplain Forest." In The Role of Natural and Constructed Wetlands in Nutrient Cycling and Retention on the Landscape. Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-08177-9_4.

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Honea, Jon M. "Challenges for Diadromous Fishes in a Dynamic Global Environment." In Challenges for Diadromous Fishes in a Dynamic Global Environment, edited by Robert J. Naiman, James M. Helfield, Krista K. Bartz, and Deanne C. Drake. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874080.ch26.

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<em>Abstract</em>.-We review the current understanding of major pathways, mechanisms, and consequences of salmon-borne marine-derived nutrients (MDN) in estuarine, freshwater, and riparian ecosystems. Semelparous Pacific salmon <em>Oncorhynchus </em>spp. acquire most of their body mass while at sea before returning to spawn and die in natal streams. The annual spawning migrations transport substantial quantities of MDN from the fertile North Pacific Ocean to relatively nutrient-poor coastal freshwater and terrestrial ecosystems. People have been long aware of the importance of salmon-borne MDN for the productivity of freshwater ecosystems in western North America, and the rapidly increasing knowledge base supports this notion. Nevertheless, many details associated with nutrient pathways, cycling processes, and the ecosystem-scale consequences of MDN transfer remain to be elucidated. The collective data suggest that freshwater portions of the salmon production system, as well as the dynamics of local terrestrial plant and animal communities, are intimately linked to MDN in complex ways. At the same time, the ecological importance of MDN, relative to other major nutrient sources, is temporally and spatially dependent and influenced by the life histories and abundances of salmonid stocks. Although interactions among climate cycles, salmon, riparian vegetation, predators, and MDN flowpaths and feedbacks are complex, they also form a wonderfully integrated ecological system with a high degree of resilience and productivity. Understanding this complex system and its inherent temporal and spatial variability requires a holistic scientific perspective that values important interactions among the salmonid life cycle, the physical setting, and the numerous linkages to other ecosystem components.

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Reynolds, James F., and Paul R. Kemp. "Modeling the Unique Attributes of Arid Ecosystems: Lessons from the Jornada Basin." In Structure and Function of a Chihuahuan Desert Ecosystem. Oxford University Press, 2006. http://dx.doi.org/10.1093/oso/9780195117769.003.0020.

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The Jornada Basin is typical of arid ecosystems of the Southwestern United States and many other regions of the globe: It is water-limited with low annual net primary production (ANPP) and low-standing crop (Szarek 1979; Ludwig 1987). Yet paradoxically, arid ecosystems are structurally and functionally quite complex, exhibiting a remarkable range of species compositions and system behaviors. This can be attributed in part to the presence of complex topography and landscape physiography (Mabbutt 1997; see also chapter 2) which, when combined with extreme variability in precipitation (Cavazos et al. 2002; Weltzin et al. 2003; see also chapter 3), produces striking spatial and temporal heterogeneity in the availability of essential limiting resources, such as water and mineral nutrients (MacMahon and Wagner 1985; see also chapters 5 and 6). In view of these complexities, one of the long-term objectives of the research in the Jornada Basin is to develop a synthetic understanding of the mechanisms and processes governing the complex patterns of arid land structure and functioning. It is clear that understanding and predicting potential cause–effect relationships will require considerable insights at multiple spatial and temporal scales (chapter 18). Models are expected to play an important role in this synthesis because most experiments and observations tend to take place at small spatial (e.g., 1–100 m2) and brief temporal scales (e.g., days, months, one to five years) (Levin 1992), whereas many ecosystem responses are the result of interacting factors and feedbacks operating over larger spatial and longer time periods (O’Neill et al. 1989; Levin 1992). In this chapter, we present a summary of some of the mechanistic models we developed as part of the Jornada Basin research program. Although our initial goal was largely focused on the relationship between precipitation and ecosystem functioning in the Jornada Basin, our work is sufficiently general that it should be applicable to other arid land regions of the world. Simulation modeling has a key role to play because it is difficult to experimentally examine even a partial spectrum of ecosystem-level responses that could result from abrupt perturbations, such as overgrazing and especially longer term external forcings, such as shifts in precipitation.

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Palis, Gary A., and Michael D. Rose. "Island Food Webs." In Island Biogeography in the Sea of Cortés II. Oxford University Press, 2002. http://dx.doi.org/10.1093/oso/9780195133462.003.0019.

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Most of this book focuses on the biogeography and ecology of plants and various animal taxa on islands in the Sea of Cortés. These chapters highlight the historical and biogeographical factors that contributed to the patterns of species distribution and co-occurrence among islands. However, these patterns also reflect the action of ecological processes because the species present interact, directly or indirectly, within the food web that occurs on any given island. Island food webs may also be unique from other communities in the degree to which their structure and dynamics are also strongly influenced by the surrounding ocean. We believe that a deeper appreciation of the trophic connections between the sea and the land, and the resulting effects on the structure and dynamics of island food webs, is key to understanding the biogeography of species on islands. Many factors that operate through the food web can enhance or depress populations in a way that affects their local distribution and persistence, and, as a consequence, affects patterns of diversity on a biogeographical scale. Of these, we recognize three as being particularly important: the availability and quality of resources, competition, and consumption (i.e., by herbivores, predators, parasites). Bottom-up factors (nutrients, primary productivity, and food availability to consumers) set limits on island productivity and hence on the potential abundance of a particular group. Within a given community, secondary productivity and population density are subsequently constrained by top-down (i.e., consumption) and competitive effects. One of our goals in this chapter is to show how processes that influence productivity of gulf islands determine patterns of abundance of organisms on islands and affect interactions among species and trophic levels in these systems. Our second goal is to demonstrate the importance of spatial and temporal variability in productivity in determining the structure and dynamics of island food webs. Using our long-term studies of plants and consumers on islands in the northern gulf, we show that productivity varies greatly, both among years and islands, as a result of both local conditions and global climatic factors. Such variable productivity markedly affects food web dynamics and ultimately the abundance of species on the islands in the Sea of Cortés.

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Changa, Taity, Jane Asiyo Okalebo, and Shaokun Wang. "Spatio-Temporal Dynamics of Soil Microbial Communities in a Pasture: A Case Study of Bromus inermis Pasture in Eastern Nebraska." In Agrometeorology [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.93548.

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Today’s intensified agricultural production is characterized by crop and pasture monocultures, which have a significant impact on soil microbial diversity and abundance. This chapter provides a case study in which the relative importance of brome grass (Bromus inermis) monoculture pasture versus intra-site microhabitat diversity is explored using fatty acid methyl ester (FAMEs) assay to delineate the presence and abundance of several classes of soil microbes instrumental in soil nutrient cycling, plant health, plant organic matter decomposition, and soil stabilization. The chapter explores spatio-temporal variability of bacteria, actinomycetes, saprophytes, mycorrhizae, and micro-eukaryotes over two durations (summer and fall) collected using two distinct sampling methods. One of the methods is commonly employed, namely, transect-based, while the other is informed by soil electroconductivity measurements conducted over the entire pasture site from a previous survey.

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Boose, Emery R. "Hurricane Impacts in New England and Puerto Rico." In Climate Variability and Ecosystem Response in Long-Term Ecological Research Sites. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195150599.003.0008.

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Hurricanes have a profound effect on many coastal ecosystems. Direct impacts often include wind damage to trees, scouring and flooding of river channels, and salt-water inundation along shorelines (Simpson and Riehl 1981; Diaz and Pulwarty 1997). In some areas, secondary impacts may include landslides triggered by heavy rains (Scatena and Larson 1991) or catastrophic dry-season fires resulting from heavy fuel loading (Whigham in press). This chapter will focus on the longterm impacts of hurricane wind damage at two LTER sites, the Harvard Forest (HFR) in central New England and the Luquillo Experimental Forest (LUQ) in northeastern Puerto Rico. These two sites, both located in the North Atlantic hurricane basin and occasionally subject to the same storms, provide interesting examples of tropical and temperate hurricane disturbance regimes. Wind damage from a single hurricane is often highly variable (Foster 1988). Damage to individual trees can range from loss of leaves and fine branches, which can significantly alter surface nutrient inputs (Lodge et al. 1991), to bole snapping or uprooting, which can significantly alter coarse woody debris and soil microtopography (Carlton and Bazzaz 1998a and b). At the stand level, damage can range from defoliation to individual tree gaps to extensive blowdowns, creating different pathways for regeneration (Lugo 2000). At landscape and regional levels, complex patterns of damage are created by the interaction of meteorological, topographic, and biological factors (Boose et al. 1994). Adding to this spatial complexity is the fact that successive hurricanes are not necessarily independent in terms of their effects. A single storm lasting several hours may have effects that persist for decades (Foster et al. 1998). And forest susceptibility to wind damage is strongly influenced by composition and structure, which in turn are strongly influenced by previous disturbance history (Foster and Boose 1992). Thus, the impacts of a single hurricane may depend in part on the impacts of earlier storms as well as on other previous disturbances and land use. Hurricanes, like other disturbances, both create and respond to spatial heterogeneity (Turner et al. 2003). To understand the long-term ecological role of hurricanes at a given site, we must consider these three sets of questions: (1) What is the hurricane disturbance regime?

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Actas de conferencias sobre el tema "Nutrients spatial variability"

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Wang, Zilong, Qiang Fu, and Qiuxiang Jiang. "Spatial Variability Analysis of Reclaimed Wetland Soil Nutrients in Sanjiang Plain, China." In 2008 4th International Conference on Wireless Communications, Networking and Mobile Computing (WiCOM). IEEE, 2008. http://dx.doi.org/10.1109/wicom.2008.2976.

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Singha, Chiranjit, and Kishore C. Swain. "Assessing The Spatial Variability of Soil Nutrients Prediction Using GIS-based Interpolation Techniques." In 2022 IEEE World Conference on Applied Intelligence and Computing (AIC). IEEE, 2022. http://dx.doi.org/10.1109/aic55036.2022.9848951.

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Tan, Qiujin, Fuping Zeng, Haisheng Chen, et al. "Spatial variability of soil nutrients in Juglans regia plantations in depressions between karst hills." In International Conference on Advances in Energy, Environment and Chemical Engineering. Atlantis Press, 2015. http://dx.doi.org/10.2991/aeece-15.2015.68.

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Yong He, HaiYan Song, ShuJuan Zhang, and Hui Fang. "Study on the Spatial Variability and the Sampling Scheme of Soil Nutrients in the Field Based on GPS and GIS." In 2005 IEEE Engineering in Medicine and Biology 27th Annual Conference. IEEE, 2005. http://dx.doi.org/10.1109/iembs.2005.1615844.

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Curcio, Christine A. "Aging and topography of human photoreceptors." In OSA Annual Meeting. Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.wc1.

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Age-related decrements in acuity and contrast sensitivity are only partially explained by the combined effects of pupillary constriction and lens opacification. The notion of a neural origin for these visual deficits remains controversial. Limited quantitative data on photoreceptors in aging suggest disorganization of both rod and cone outer segments, displacement of nuclei, and outright cell loss, particularly in the fovea. The relationship of these phenomena to nonpathological changes in retinal supporting tissues which may impair transport of nutrients across the outer blood–retinal barrier

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Zheng, Hongbo, Jianping Wu, and Shan Zhang. "Study on the Spatial Variability of Farmland Soil Nutrient Based on the Kriging Interpolation." In 2009 International Conference on Artificial Intelligence and Computational Intelligence. IEEE, 2009. http://dx.doi.org/10.1109/aici.2009.137.

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Shen, Guangrong, Zhenhua Qian, Jingjing Xu, and Apostolos Sarris. "Spatial Variability of Soil Nutrient in Chongming of Shanghai, China by Using GIS and Kriging Method." In 2009 WRI Global Congress on Intelligent Systems. IEEE, 2009. http://dx.doi.org/10.1109/gcis.2009.72.

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Informes sobre el tema "Nutrients spatial variability"

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Seasonal and spatial variability of nutrients and pesticides in streams of the Willamette Basin, Oregon, 1993-95. US Geological Survey, 1998. http://dx.doi.org/10.3133/wri974082c.

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Spatial and seasonal variability of nutrients, pesticides, bacteria, and suspended sediment in the Santee River basin and coastal drainages, North and South Carolina, 1995-97. US Geological Survey, 2000. http://dx.doi.org/10.3133/wri004076.

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