Studies On Nutrient Release And Related Research In Tobacco Planting Soil Of Organic Fertilizer

This article used organic mixed fertilizer for materials, did the research of degradation and nutrient mineralization rates in different temperature and water supply conditions. The degradation of soil enzyme activities and microbial activity characteristics were analyzed at the same time. The results are as follows:1. The total of every single nutrient mineralization of organic mixed fertilizer in different temperatures and the water supply conditions are different. Total mineralization of potassium is maximum at35℃, the water content70%～75%and minimum in10℃, alternating wet and dry treatments of30%to70%. Total mineralization of nitrogen is maximum at25℃, saturated water content processing and minimum in10℃alternating wet and dry30%to70%processing. Total mineralization of phosphorus is maximum at35℃, saturated water treatments and minimum in10℃, the water content of70%to75%. Total mineralization of organic carbon is maximum in35℃, saturated water treatments and minimum in10℃, alternating wet and dry30%to70%processing.Each nutrient mineralization rate is different in the incubation time. Overall, the nutrient mineralization rates in the order of K> P> N> C.35℃, the water content of70%to75%treated with the potassium,35℃, the water content of70%to75%treated with the potassium,35℃, saturated water treatments with the nitrogen and phosphorus is maximum of mineralization rate in first10days. The organic carbon mineralization rates in the35℃, saturated water content processing is maximum at40days after culturing. Potassium, nitrogen and phosphorus mineralization rate reach to peak in the first culture days and then decreased with increasing incubation time. Mineralization rate of organic carbon is first and then decreased in the first and middle culture days and decreased in the later culture days.2. CAT, URE, CEL activity are reduced in the low temperature. Three kinds of enzyme activity are in maximum in35℃, saturated water treatments. The peak of CAT activity appear in cultured10days; URE activity peak appear in the culture25days about; the first peak of CEL appear in cultured10days and the second in cultured40days. Three kinds of enzyme activity decreased in varying degrees in later cultured days.3. The total number of soil bacteria, fungi and actinomycetes increased gradually with increasing incubation time. The numbers of three fungi have reached the maximum in70days after culturing35℃, saturated water content of the largest processing of the total bacterial while25℃, saturated water content processing with fungus and35℃,70%water content treatments with actinomycetes. Microbial diversity index (H) and Evenness (E) also peaked about culturing70days.25℃, saturated water content processing and35℃. saturated water content processing is optimal treatment.