论文部分内容阅读
在整个果树生长期内，秸杆覆盖可明显增加各土层固氮菌的数量，２０ ｃｍ土层中，年平均固氮菌数量增加１２３．８０％；２０－ ４０ ｃｍ土层中增加５１．６１％；４０－ ６０ ｃｍ土层中增加１０３．８５％。在 ０－６０ｃｍ果树的耕作层内固氮菌数量年平均增加９５．４７％，不同土层固氮菌数年变化曲线，无论覆盖与对照，均呈单峰曲线变化，高峰出现在９月。
During the whole growing season of fruit trees, the straw cover could obviously increase the number of azotobacter in each soil layer. The number of annual nitrogen-fixing bacteria increased by 123.80% in 20 cm soil layer and 51.61% in 20-40 cm soil layer, While in the 40-60 cm soil layer, it increased by 103.85%. The number of nitrogen-fixing bacteria in cultivated layer of 0-60cm fruit trees increased by 95.47% on average, and the number-year curve of nitrogen-fixing bacteria in different soil layers showed a single-peak curve change in coverage and control. The peak appeared in September.