Atmospheric Deposition Of Tibet's Main Crop Nitrogen Nutrition

Since the industrial revolution, especially in large-scale development of synthetic ammonia industry has been caused by human activities, atmospheric reactive nitrogen emissions increased dramatically through the atmospheric circulation around the region and the impact on air quality around the world and nitrogen deposition process, a more natural subsidence increased the number of nutrients from the environment and its impact on the affected farmland nutrient cycling has also attracted more and more attention. In this paper, the passive sampler and a small volume sampler and a 15N dilution technique based on a comprehensive set of nitrogen system (Integral Total Nitrogen Input, referred to as ITNI system), a preliminary study of atmospheric nitrogen dry and wet deposition, morphology and dynamic change, I zone main crops - barley, wheat, the impact of nutrition.Nyingtri areas in the two related trial of a preliminary study of atmospheric nitrogen dry and wet deposition, morphology and dynamic change; test two pairs of barley, wheat nitrogen fertility during the environment (mainly dry and wet deposition of nitrogen) of farmland input have been studied, and based on previous work to further explore different at different growth stages, 15N Nyingtri supply level of regional agro-ecosystem in the number of environmental nitrogen and its impact on the effectiveness of plants. The major findings of this paper are summarized as follows:2007 ~ 2008 year, the dry deposition amount of 2.9 kg hm-2, at the same time period (July 2007-May 2008) wet deposition of 2.64 kg hm-2, the total amount of nitrogen deposition 5.54 kg hm-2, dry and wet deposition than close to 52/48, in May 2006 ~ October 2008 the total amount of atmospheric nitrogen deposition is about 19.2 kg hm-2. Wet deposition, the organic nitrogen accounted for more than 70% of total nitrogen, atmospheric nitrogen wet deposition is the main component, inorganic nitrogen, ammonium nitrogen, nitrate-N is almost equally divided. Dry deposition, the deposition rate of ammonia nitrogen is slightly higher than the two years of the settlement were 2.4 kg hm-2, 0.5 kg hm-2, ammonia nitrogen concentration was 3.8 times the concentration of both the highest, lowest values appear in the summer, winter, summer, the concentration of ammonia to 0.62μg m-3, winter 1.30μg m-3, a difference of nearly 2-fold; summer concentration of nitrogen dioxide 0.48μg m-3, winter only to 0.01μg m-3, a difference of up to 48 times. Atmospheric nitrogen through dry and wet deposition comparative study found that dry deposition of atmospheric nitrogen is the main source of atmospheric deposition, dry deposition and wet deposition almost equal amount of both mixed settlement of wet deposition is about 2 times that of atmospheric dry deposition nitrogen deposition has a very important contribution.Normal levels for nitrogen, barley seedling to jointing stage input of atmospheric nitrogen deposition for 7.46 kg hm-2, throughout the growth period the total atmospheric input of nitrogen to 7.95 kg hm-2, the effectiveness of nitrogen deposition to plant 3.05 kg hm-2, accounting for 38.5% of total nitrogen input; normal levels for nitrogen, the jointing stage of wheat seedlings to atmospheric nitrogen deposition input of 7.29 kg hm-2, throughout the growth period the total atmospheric input of nitrogen to 9.49 kg hm-2, the effectiveness of plant nitrogen deposition for 1.63 kg hm-2, accounting for 17.2% of total nitrogen input. Different nitrogen levels for the environment will affect the agricultural nitrogen input, the input of atmospheric nitrogen deposition system accounts for the ratio of total nitrogen content with increasing nitrogen application rate lower. Environment, such as atmospheric nitrogen deposition of nitrogen is the main crop Nyingtri highland barley, wheat, an important growth nutrient input, nutrient resources in the management of the environment as a result of the contribution of nitrogen, cultivation of barley can be saved at least 3 kg hm-2 of nitrogen input, when the cultivation of wheat can save at least 1.6 kg hm-2 inputs of nitrogen fertilizer at the same time, the normal nitrogen level for both crops in favor of the use of the atmospheric environment to absorb nitrogen, but also to ensure crop nutrition, quality.