نتایج جستجو برای: n leaching loss

تعداد نتایج: 1393587  

Journal: :پژوهش علف های هرز 0
امید الستی دانشجوی دکتری دانشگاه علوم و کشاورزی و منابع طبیعی گرگان جاوید قرخلو دانشگاه علوم کشاورزی و منابع طبیعی گرگان

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2017
Rebecca E. Shelton Krista L. Jacobsen Rebecca L. McCulley

Agroecosystem nitrogen (N) loss produces greenhouse gases, induces eutrophication, and is costly for farmers; therefore, conservation agricultural management practices aimed at reducing N loss are increasingly adopted. However, the ecosystem consequences of these practices have not been well-studied. We quantified N loss via leaching, NH3 volatilization, N2O emissions, and N retention in plant ...

2017
Tao Huang Xiaotang Ju Hao Yang

Nitrate leaching is one of the most important pathways of nitrogen (N) loss which leads to groundwater contamination or surface water eutrophication. Clarifying the rates, controlling factors and characteristics of nitrate leaching is the pre-requisite for proposing effective mitigation strategies. We investigated the effects of interactions among chemical N fertilizer, straw and manure applica...

2001
S. G. Sommer

Nitrogen and carbon emissions and plant nutrient leaching during storage of solid deep litter from dairy cow houses was examined in this study. Included was an assessment of the potential for reducing emission and leaching losses by compaction, mixing and by covering the deep litter. During a composting period of 132 days from October 1998 to March 1999, emissions of NH3, N2O and CH4 and leachi...

2009
K. C. Cameron Z. He

Nitrate (NO3 ) can contribute to surface water eutrophication and is deemed harmful to human health if present at high concentrations in the drinking water. In grazed grassland, most of the NO3 -N leaching occurs from animal urine-N returns. The objective of this study was to determine the effectiveness of a nitrification inhibitor, dicyandiamide (DCD), in decreasing NO3 ) leaching in three dif...

Journal: :Environmental pollution 2012
Minghua Zhou Bo Zhu Klaus Butterbach-Bahl Tao Wang Jessica Bergmann Nicolas Brüggemann Zhenhua Wang Taikui Li Fuhong Kuang

This study provides a combined dataset on N loss pathways and fluxes from sloping cropland in the purple soil area, southwestern China. A lysimeter experiment was conducted to quantify nitrate leaching (May 2004-May 2010) and N(2)O emission (May 2009-May 2010) losses. Nitrate leaching was the dominant N loss pathway and annual leaching fluxes ranged from 19.2 to 53.4 kg N ha(-1), with significa...

Journal: :Ecology 2007
Feike A Dijkstra Jason B West Sarah E Hobbie Peter B Reich Jared Trost

In nitrogen (N)-limited systems, the potential to sequester carbon depends on the balance between N inputs and losses as well as on how efficiently N is used, yet little is known about responses of these processes to changes in plant species richness, atmospheric CO2 concentration ([CO2]), and N deposition. We examined how plant species richness (1 or 16 species), elevated [CO2] (ambient or 560...

2002
DI Hong

Over the past decade, there has been a rapid increase in dairy farming in New Zealand. Nitrate leaching from intensive agricultural systems, e.g. dairy farms, is suspected to cause increased nitrate concentrations in ground and surface waters. The objective of this research programme was to determine nitrate leaching losses on dairy pasture systems as affected by the application of dairy shed e...

Journal: :مدیریت خاک و تولید پایدار 0
امیر بهزاد بذرگر استادیار گروه زراعت، دانشگاه آزاد اسلامی، واحد نیشابور افشین سلطانی استاد گروه زراعت دانشگاه علوم کشاورزی و منابع طبیعی گرگان علیرضا کوچکی استاد گروه زراعت دانشکده کشاورزی دانشگاه مشهد ابراهیم زینلی استادیار گروه زراعت دانشگاه علوم کشاورزی و منابع طبیعی گرگان علیرضا قائمی استادیار بخش تحقیقات چغندرقند، مرکز تحقیقات کشاورزی و منابع طبیعی خراسان رضوی امیر حجارپور مدرس گروه علوم کشاورزی دانشگاه پیام نور ایران

nitrogen is one of the most important nutrients in crop production, but it's losses to the environment is harmful. the sundial model (simulation model of n dynamics in the soil) was used to quantify the cycle of n and it's losses in different production systems of sugar beet (beta vulgaris l.) in former khorasan province, east of iran. the data were collected from traditional, semi-me...

Journal: :Journal of environmental quality 2009
Chris van Kessel Tim Clough Jan Willem van Groenigen

Conventional wisdom postulates that leaching losses of N from agriculture systems are dominated by NO(3)(-). Although the export of dissolved organic nitrogen (DON) into the groundwater has been recognized for more than 100 yr, it is often ignored when total N budgets are constructed. Leaching of DON into stream and drinking water reservoirs leads to eutrophication and acidification, and can po...

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