Abstract:

In order to know the response of soil microbial characteristics and grass growth on different improvement measures in saline-alkali soil in Ningxia, the effects of soil microflora, microbial community diversity and the correlation analysis among soil microbial diversity, microorganisms number, and alfalfa biomass were studied in a field experiment after applied with straw, organic fertilizer, flue gas desulfurization waste and saline-alkali soil amendment in saline-alkali soil in Ningxia. The results showed that: four improvement measures had a clear role in promoting the alfalfa plant height and yield, alfalfa plant height increased by 13.8% to 33.3%, alfalfa dry weight increased by 21.9% to 125.0%, the order followed by the performance of organic fertilizer > straw > improved agent desulfurization waste > control. The four improvement measures increased the soil microbial community carbon source utilization capacity, richness and diversity index, principal component analysis showed that, the greater impact carbon source on soil microbial were 2-hydroxy acid, alpha-cyclodextrinrefined, D-xylose, phenylethylamine, glycogen, etc. Desulfurization waste, conditioner and organic fertilizer treatments increased the proportion of bacteria in the soil microbial amount, reducing the proportion of actinomycetes and fungi. The positive significant correlation existed between soil microbial quantity, microbial diversity and the alfalfa plant height, yield of each treatment. That mean the saline-alkali soil bacteria amount, actinomycetes amount, microbial diversity can be used as biological indicators of the effects evaluation in saline-alkali soil improvement.