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土壤微生物在维持生态系统结构、功能和过程方面发挥着重要作用。为了解半干旱沙区生物结皮中微生物数量与土壤理化性质之间的关系,对毛乌素沙地南缘沙丘生物结皮及下层土壤(0—5和5—10 cm)微生物数量和理化性质进行了测定。结果表明:结皮层微生物数量大于结皮下层,结皮层微生物总数和细菌、放线菌、真菌数量随生物结皮的发育呈增加的趋势;结皮层细颗粒物含量高于结皮下层,结皮下层土壤中细颗粒物随生物结皮的发育呈增加的趋势;结皮层有机质、全氮和全磷含量大于结皮下层,结皮层有机质、全氮含量随生物结皮的发育呈先减少后增加的趋势,全磷含量随生物结皮的发育呈增加的趋势;微生物数量与土壤沙粒含量呈显著或极显著负相关关系,与粉粒、黏粒等细颗粒物和有机质、全氮、碱解氮等养分含量呈显著或极显著正相关关系,表明这些指标的变化能够敏感地指示微生物数量的变化。
Soil microorganisms play an important role in maintaining the structure, function and process of ecosystems. In order to understand the relationship between the number of microbes and the physico-chemical properties of soil in the semi-arid sandy littoral area, the microbial population and physicochemical properties of the biological crusts and the lower soil layers (0-5 and 5-10 cm) in the southern margin of the Mu Us Sandland The determination. The results showed that the number of microorganisms in the crusts was larger than that in the lower crusts, and the total number of microorganisms and the number of bacteria, actinomycetes and fungi in the crusts increased with the development of the biological crusts. The content of fine particles in the crusts was higher than that in the lower crusts and the lower crusts The fine particles in soil showed an increasing tendency with the development of biological crusts. The contents of organic matter, total nitrogen and total phosphorus in the crusts were greater than those in the lower crusts. The contents of organic matter and total nitrogen in the crusts decreased and then increased with the development of the biological crusts , Total phosphorus content increased with the development of biological crusts. There was a significant or extremely significant negative correlation between microbial quantity and soil sand content, with fine particulates such as silt and clay and organic matter, total nitrogen and alkaline hydrolysis nitrogen Nutrient content showed a significant or very significant positive correlation, indicating that changes in these indicators could sensitively indicate changes in the number of microorganisms.