نتایج جستجو برای: point nitrogen pollution and soil erosion

تعداد نتایج: 16946384  

2013
Jiwen Ge Guihua Ran Wenjie Miao Huafeng Cao Shuyuan Wu Lamei Cheng

To provide the reasonable basis for scientific management of water resources and certain directive significance for sustaining health of Gufu River and even maintaining the stability of water ecosystem of the ThreeGorge Reservoir of Yangtze River, central China, multiple statistical methods including Cluster Analysis (CA), Discriminant Analysis (DA) and Principal Component Analysis (PCA) were p...

Journal: :Journal of environmental management 2006
Shu-Kuang Ning Ni-Bin Chang Kai-Yu Jeng Yi-Hsing Tseng

Soil erosion associated with non-point source pollution is viewed as a process of land degradation in many terrestrial environments. Careful monitoring and assessment of land use variations with different temporal and spatial scales would reveal a fluctuating interface, punctuated by changes in rainfall and runoff, movement of people, perturbation from environmental disasters, and shifts in agr...

Journal: :Global change biology 2014
Tobias Ceulemans Carly J Stevens Luc Duchateau Hans Jacquemyn David J G Gowing Roel Merckx Hilary Wallace Nils van Rooijen Thomas Goethem Roland Bobbink Edu Dorland Cassandre Gaudnik Didier Alard Emmanuel Corcket Serge Muller Nancy B Dise Cecilia Dupré Martin Diekmann Olivier Honnay

Nutrient pollution presents a serious threat to biodiversity conservation. In terrestrial ecosystems, the deleterious effects of nitrogen pollution are increasingly understood and several mitigating environmental policies have been developed. Compared to nitrogen, the effects of increased phosphorus have received far less attention, although some studies have indicated that phosphorus pollution...

2010
Jinheng Zhang Junqiang Wang Yongliang Lv Jianting Liu Dapeng Li Zhenxuan Yao Xi Jiang Ying Liu

This research combined data from soil, terrain and meteorological surveys, with quantitative data from soil and water field studies to determine the leaching processes of nitrogen and phosphorus contaminants from field vegetation into the Dagu River. Using the Gray correlation analysis method, precipitation and irrigation were established as the major driving force behind leaching losses from c...

ژورنال: علوم آب و خاک 2018

To assess the effects of different levels of soil lead on mineralization of organic carbon and nitrogen, a factorial pot experiment was conducted using litter bag method. The factors examined were different levels of soil lead (0, 25, 50, 100, and 200 mg kg-1soil) and incubation periods (1, 2, 3 and 4 months) in three replications. At the end of incubation periods, the litter bags were pulled o...

2007
S. K. Papiernik

Soil movement by tillage redistributes soil within the profile and throughout the landscape, resulting in soil removal from convex slope positions and soil accumulation in concave slope positions. Previous investigations of the spatial variability in surface soil properties and crop yield in a glacial till landscape in west central Minnesota indicated that wheat (Triticum aestivum) yields were ...

ژورنال: آبخیزداری ایران 2021

The process of splash of soil particles by raindrops and their transport by splash or surface shallow flow is considered as interrill erosion, which can reduce soil fertility and cause pollution of surface water. This research was carried out to investigate the temporal variation of interrill erosion in different soils affected by surface slope. For this purpose, laboratory experiments were car...

2011
R. C. John A. Y. Itah J. P. Essien D. I. Ikpe

The effect of crude oil on the growth of legumes (Calopogonium muconoides and Centrosema pubescens) and fate of nitrogen-fixing bacteria in wetland ultisol was investigated using standard cultural techniques. The results revealed observable effects of oil on soil physico-chemistry, plant growth and nodulation as well as on densities of heterotrophic, hydrocarbonoclastic and nitrogen fixing bact...

Journal: :مرتع و آبخیزداری 0
کاظم نصرتی دانشیار دانشکدة علوم زمین دانشگاه شهید بهشتی فروزان احمدی دانشجوی دکتری ژئومورفولوژی - مدیریت محیطی، دانشگاه شهید بهشتی علی اکبر نظری سامانی دانشیار دانشکدة منابع طبیعی دانشگاه تهران محمد رضا ثروتی استاد دانشکدة علوم زمین دانشگاه شهید بهشتی

soil erosion is one of the most destructive phenomena which cause significant ecological changes in many areas. soil conservation and erosion control is essential because of the irreparable damage caused by soil erosion. soil conservation programs will not achieve until to find adequate methods of combating land degradation and ways to reduce the sediment. therefore, we need to have enough know...

2018
Maya Almaraz Edith Bai Chao Wang Justin Trousdell Stephen Conley Ian Faloona Benjamin Z Houlton

Nitrogen oxides (NO x = NO + NO2) are a primary component of air pollution-a leading cause of premature death in humans and biodiversity declines worldwide. Although regulatory policies in California have successfully limited transportation sources of NO x pollution, several of the United States' worst-air quality districts remain in rural regions of the state. Site-based findings suggest that ...

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