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Evaluation of best management practices under intensive irrigation using SWAT model

Journal Articles & Books
Dezembro, 2013
Espanha

Land management practices such as conservation tillage and optimum irrigation are routinely used to reduce non-point source pollution and improve water quality. The calibrated and validated SWAT-IRRIG model is the first modified SWAT version that reproduces well the irrigation return flows (IRF) when the irrigation source is outside of the watershed. The application of this SWAT version in intensive irrigated systems permits to better evaluate the best management practices (BMPs) in such systems.

Land management between crops affects soil inorganic nitrogen balance in a tropical rice system

Journal Articles & Books
Dezembro, 2014
Filipinas

Sustainable production of lowland rice (Oryza sativa L.) requires minimising undesirable soil nitrogen (N) losses via nitrate (NO₃⁻) leaching and denitrification. However, information is limited on the N transformations that occur between rice crops (fallow and land preparation), which control indigenous N availability for the subsequent crop. In order to redress this knowledge gap, changes in NO₃⁻isotopic composition (δ¹⁵N and δ¹⁸O) in soil and water were measured from harvest through fallow, land preparation, and crop establishment in a 7 year old field trial in the Philippines.

Comparative diet selection by cattle and sheep grazing two contrasting heathland communities

Journal Articles & Books
Dezembro, 2009

In the UK the funding mechanism for moorland restoration is being implemented primarily through agri-environment schemes, yet to date remarkably few comparative grazing studies with domesticated livestock have been conducted on this type of vegetation community. In this experiment the diet composition of four groups of animals grazing heathland swards with low (8%) and high (61%) percentages of cover of Calluna vulgaris was estimated from faeces profiles of n-alkanes and long-chain fatty alcohols.

Terrestrial carbon balance in tropical Asia: Contribution from cropland expansion and land management

Journal Articles & Books
Dezembro, 2013
Ásia
Ásia Meridional

Tropical Asia has experienced dramatic cropland expansion and agricultural intensification to meet the increasing food demand and is likely to undergo further rapid development in the near future. Much concern has been raised about how cropland expansion and associated management practices (nitrogen fertilizer use, irrigation, etc.) have affected the terrestrial carbon cycle in this region.

Ecological consequences of the expansion of N₂-fixing plants in cold biomes

Journal Articles & Books
Dezembro, 2014

Research in warm-climate biomes has shown that invasion by symbiotic dinitrogen (N₂)-fixing plants can transform ecosystems in ways analogous to the transformations observed as a consequence of anthropogenic, atmospheric nitrogen (N) deposition: declines in biodiversity, soil acidification, and alterations to carbon and nutrient cycling, including increased N losses through nitrate leaching and emissions of the powerful greenhouse gas nitrous oxide (N₂O).

Classification of Leafy Spurge With Earth Observing-1 Advanced Land Imager

Journal Articles & Books
Dezembro, 2006

Leafy spurge (Euphorbia esula L.) is an invasive exotic plant that can completely displace native plant communities. Automated techniques for monitoring the location and extent of leafy spurge, especially if available on a seasonal basis, could add greatly to the effectiveness of control measures. As part of a larger study including multiple sensors, this study examines the utility of mapping the location and extent of leafy spurge in Theodore Roosevelt National Park using Earth Observing-1 satellite Advanced Land Imager (ALI) scanner data.

Spatial controls on dissolved organic carbon in upland waters inferred from a simple statistical model

Journal Articles & Books
Dezembro, 2015

Dissolved organic carbon (DOC) concentrations in upland surface waters in many northern hemisphere industrialised regions are at their highest in living memory, provoking debate over their “naturalness”. Because of the implications for drinking water treatment and supply there is increasing interest in the potential for mitigation through local land management, and for forecasting the likely impact of environmental change. However, the dominant controls on DOC production remain unresolved, hindering the establishment of appropriate reference levels for specific locations.

contribution of carbon-based payments to wetland conservation compensation on agricultural landscapes

Journal Articles & Books
Dezembro, 2011

This paper evaluates the potential of payments for carbon sequestered through wetland and riparian conservation, to offset the costs of publicly funded wetland conservation programs. In particular, the research focuses on quantifying the value of carbon sequestered in wetland and riparian zones of the Prairie Pothole Region in the province of Saskatchewan.