Study On Variation Features Of Nitrogen Of Karst Rocky Desertification Soil And Ecological And Environmental Effect In Guizhou

Study on Variation Features of Nitrogen of Karst Rocky Desertification Soil And Ecological And Environmental Effect in GuizhouAbstract: This study has discussed variation features of Nitrogen of KarstRocky Desertification soil at different degrees of Karst Rocky Desertification , in different areas, and under different ecological modes, as well as at different levels of soil profiles separately, then discuss ecological and environmental effect on this basis. The main conclusions are as follows:(1) The content of soil Ammonium Nitrogen and Nitre Nitrogen makes no variation regularity.(2) Compared with Karst no-Rocky Desertification soil, the content of soil Organic Matter and Nitrogen in various degrees of Karst Rocky Desertification shows a tendency to drop suddenly. The content of soil Organic Matter, Total N, Total Acid-hydrolysable N, amino acid N and Alkali-soluble N decreases with the degradation of degrees of Karst Rocky Desertification, but the content of other nitrogen does not display the same variation law.(3) Compared with Karst no-Rocky Desertification soil (forest soil), the content of desertification soil Organic Matter and Nitrogen (farming soil, meadow soil, and de-farming soil)under different ecological modes show a tendency to drop suddenly in the Karst Rocky Desertification area. But the variation laws of content of different shape nitrogen have nothing in common among them. The content of desertification soil Organic Matter and Nitrogen is as follows: forest soil > meadow soil in Karst no-Rocky Desertification t area (south in Gguizhou), but the disparity is relatively little compared with Karst Rocky desertification area.(4)The content of different nitrogen has different variation laws in different areas.(5)Except for soil Amino-sugar N under different ecological modes and Total Acid-hydrolysable N at different areas, the variation tendency of percentage of organic nitrogen taking up total nitrogen is consistent with their content at different degrees of Karst Rocky Desertification , in different areas, and under different ecological modes.(6) The content of Organic matter and Nitrogen mainly concentrates on top layer in soil profiles, and they and the percentage of organic nitrogen taking up total nitrogen reduce gradually with the depth of soil level increasing, but the proportion of acid-insoluble N accounting for total nitrogen increases progressively.(7) The content of sand grain of strongest rocky desertification soil is high, and the sandification is serious. Except for that , the proportion of sand grain, flour sand grain and glue grain in the top soil layer is more appropriate in Guizhou, and the content of glue grain decreases and increases respectively with the degree of rocky desertification and soil...