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With the development of agriculture, agricultural waste is increasing. Agricultural waste in the environment to some extent caused by the pollution. Agricultural waste, rich in organic matter and crop nutrient elements required, is an important organic fertilizer resources. Nitrogen fertilizers in improving crop yields has played a positive role, but the long-term single application of nitrogen fertilizer can cause soil compaction, soil fertility decline, affecting crop yield, stable yield. The soil enzyme can be used as one of the indicators of soil fertility evaluation. Field trials conducted in Mei County, Shaanxi Province, in June 2008 - March 2010, the analysis of the determination of soil invertase, urease, alkaline phosphatase activity and summer corn, winter wheat production and soil physical and chemical properties to study the functional diversity of soil microbial communities, to investigate nitrogen levels under different organic fertilizer conditions on the dynamic changes of soil hydrolase activity, crop yield and soil microbial communities, to provide a theoretical basis for better fertilize the soil. Study involving zero (M0, 0 kg/hm2), low (M1, 7500 kg/hm2), medium (M2, 22500 kg/hm2), (M3, 37500 kg/hm2) organic fertilizer conditions and zero (N0 , 0 kg/hm2), (N1, 60 kg/hm2), (N2, 120 kg/hm2), (N3, 180 kg/hm2) 4 Ge nitrogen levels. The results show that: 1. Corn - wheat growing period, soil hydrolase activity has the dynamic characteristics of the same dynamic characteristics of different nitrogen treatments organic fertilizer level activity similar but different enzyme activities showed different dynamic changes in the trend. Average invertase activity from corn - wheat growth period, the zero level of organic fertilizer, N1, N2 and N3 treatment were higher than N0 treatment the N2 handling the highest 25.37 mg glucose / (g.24h). The low level of organic fertilizer, N3 processing gt; the N0 processing gt; N1, N2 treatment. N1 treatment was the highest level of organic fertilizer, 11.51% higher than the N0 treatment. The high level of organic fertilizer, N1, N2 and N3 treatments were higher than N0 processing 17.87%, 19.37% and 31.61% respectively, and N0 difference was significant (P lt; 0.05). Zero nitrogen treatment, the M2 level gt; M1 level gt; M0, M3 level. In the rest of the nitrogen treatments, M2 levels gt; M0 level gt; M1, M3 level. Different organic fertilizer and nitrogen fertilizer treatment were compared M2N1 handle a maximum 31.11 mg glucose / (g.24h) than M0N0 processing 74.38% higher. 3 corn - wheat growing period average urease activity compared to zero organic fertilizer and the low level of organic fertilizer, N1 processing gt; the N0 processing gt; N2, N3 treatment. The highest level of organic fertilizer, N0 processing, 1.15 mg NH3-N / (g.24h). The high level of organic fertilizer, N3 processing gt; the N0 processing gt; N1, N2 treatment. Zero nitrogen fertilizer and low nitrogen treatments M2 level gt; M0 level gt; M1, M3 level. In nitrogen treatments, M2 levels than M0, M1 and M3 level higher than 29.31%, 37.04% and 23.33%, significantly (P lt; 0.05), and the M2 level with the rest of the level difference. In the processing of high-nitrogen fertilizer, M2, M3 level gt; M0 level gt; M1 level. From organic manure and nitrogen fertilizer with Shidui Ping urea activity, the highest M2N0 treatment 1.15 mg of NH3-N / (g.24h), 46.09% higher than M0N0 processing. Average alkaline phosphatase activity from corn - wheat growth period, zero organic fertilizer and organic fertilizer level, N1, N2 and N3 treatment were higher than N0 treatment, of which the highest N2 treatment. Low levels of organic fertilizer, N1 treatment was the highest, 2.30 mg phenol / (g.24h). High level of organic fertilizer, N1, N2 processing gt; the N0 processing gt; the N3 deal with. Zero nitrogen fertilizer and low nitrogen treatments M1 level gt; M0 level gt; levels of M2 and M3. Zero nitrogen fertilizer and high-nitrogen fertilizer processing, M0 level of the highest, each level of difference was not statistically significant (P gt; 0.05). Different organic fertilizer and nitrogen fertilizer processing the comparison, M2N0 handle the lowest, 1.85 mg phenol / (g.24h), no significant difference of the rest of processing, which M1N0 and M1N1 treatment. From the different levels of organic fertilizer nitrogen application on corn grain yield of view, the low level of organic fertilizer, N1, N2 and N3 treatment were higher than N0 processing N2 treatment highest level of the remaining organic fertilizer, N1 processing gt ; N2, N3 processing gt; N0 treatment. Zero nitrogen treatment, M1, M2 and M3 of water on average higher than the M0 level M2 highest levels of low-nitrogen fertilizer processing, M2, M3 level gt; M0 level gt; M1 level of nitrogen fertilizer processing, M1, M3 level gt ; M0 level gt; M2 level, high-nitrogen fertilizer processing, M0 the highest levels, and each level of the difference was not significant (P gt; 0.05). Comparison of different organic fertilizer and Nitrogen Fertilizer processing, M3N1 treatment was the highest, 1.41 times higher than M0N0 treatment. From the different levels of organic fertilizer nitrogen application on wheat grain yield, high levels of organic fertilizer, N1, N2 and N3 treatment than N0 treatment increased by 14.4% to 36.4%, the highest N3 treatment, the remaining level of organic fertilizer, N2 processing gt; N1, N3 treatment the gt; N0 processing. Zero nitrogen fertilizer and nitrogen treatments, the the M2 the highest level of 40.2% and 14.0%, respectively, higher than the M0 level differences reached a significant level (P lt; 0.05), low N treatment, M2 levels higher than the M0 level of 8.0% high nitrogen fertilizer processing, M3 level gt; M2 level gt; M1 level gt; M0 level. Comparison of different organic fertilizer and Nitrogen Fertilizer processing, M2N2 handling the highest, 97.0% higher than the M0N0 treatment. The correlation analysis showed that corn grain yield and soil available K was a significant positive correlation. Soil sucrase total potassium was significantly positively related to soil urease activity and total nitrogen content was significantly positively related to soil alkaline phosphatase activity and organic matter, available phosphorus was significantly positively related. Nitrogen levels on corn growth period functional diversity of soil microbial communities see, N1, N2 and N3 microbial community carbon source utilization (AWCD), the microbial communities Shannon index (H) and the microbial community richness index (S) were higher than N0 treatment, of which the highest N2 treatment. Principal component analysis showed obvious differences in microbial functional diversity of different nitrogen levels, the main carbon source of differentiation from the sugars and amino acids.
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