Responses Of Soil Nutrient To Simulated Nitrogen Deposition In A Typical Mixed Broadleaved-Korean Pine Forest

With the development of the society, the harm of nitrogen deposition has increasingly become the hot issues of global concern, especially impact on forest ecosystem. This study in a typical broadleaved-Korean pine (Pinus koraiensis) forest set up12of20m*20m samples, each sample has10m wide belt between parties, in case of causing interference between the groups. With diameter at breast height measurement sample all diameter at breast height is greater than or equal to2cm of woody plants, and recorded, diameter at breast height, tree height and coordinate, and hanging tree brand of aluminum. According to the domestic and foreign similar research and reference for the local amount of nitrogen deposition, applying nitrogen content is divided into four treatment groups, and to control (N0,0kg· hm-2a-1), low nitrogen (N1,30kg, hm-2, a-1), the nitrogen (N2,60kg, hm-2, a-1), high nitrogen (N3,120kg·m-1, a-2), three repeat each processing. In June2008to August2010,6-8month early in the form of solution spraying CO (NH2)2, soil nutrients, organic carbon content in the experimental process changes and their mutual relations.Different concentrations of nitrogen and tree with different concentration in different layer of soil nutrient content changes. Nitrogen deposition on soil total nitrogen content were not significantly influence overall, in terms of soil depth, N1level of20-40cm soil total nitrogen content increased but the difference was not significant,40～60cm in N1levels increased significantly; Significantly increased nitrogen deposition is hydrolysis nitrogen content in deep soil layer, and the influence on the hydrolysis of nitrogen content in the shallow soil was not significant; Nitrogen deposition significantly reduce soil available p content and available k content in0-20cm soil layer N3treatment significantly reduce,20～40,40～60cm soil layer N1, N2treatment significantly increased; Excess nitrogen deposition caused by excess nitrogen in the soil in the form of NO3-leaching from soil, and K+ions from the soil caused by leaching, and this study0-20cm rapidly-available potassium content reduced, other soil content may be due to the leaching of soil K+precipitation caused to migrate in the subsoil.In this study, nitrogen deposition on the whole, significantly increased the soil organic carbon content, and the0～20cm of soil organic carbon content had no significant effect, other content of the soil under the N1, N2, level increased significantly.The fitting degree of each element of organic carbon and soil size of nitrogen> total nitrogen> hydrolysis available p>phosphorus, potassium shows that the change of total nitrogen is more obvious than other nutrients to influence the content of soil organic carbon.