不同土地利用类型土壤微生物群落特征及其影响因素

Microbial community characteristics and its influence under different land types

土壤微生物群落结构特征能够提前反映土壤环境质量的变化,是土壤质量评价的重要因子。为弄清不同土地利用类型土壤微生物群落特征及其影响因素,以内蒙古呼和浩特赛罕区为研究区,从绿地、园林地、耕地以及荒废地4种不同土地利用类型土壤进行采样研究。研究结果表明:4种不同土地利用类型土壤中主要菌种为细菌、真菌以及放线菌,放线菌比例最大,其次是细菌,真菌比例最小。采样深度、温度、土地利用类型及含水率均影响微生物群落特征。随着采样深度的增加,4种土地利用类型土壤中微生物数量不断减少,0~10 cm微生物总数最多。荒废地土壤微生物数量最多,因为荒废地土层中有机质含量高,为微生物的生长提供了营养物质。含水率过高或过低均不利于微生物生长,当处于最佳含水率时微生物数量最大。对于绿地和园林地而言,最佳含水率为10%~15%,耕地最佳含水率为15%~20%,荒废地最佳含水率为10%左右。

The characteristics of soil microbial community can reflect the changes of soil environmental quality in advance.Therefore it is a vital factor for evaluating soil quality.The characteristics of microbial communities and their influencing factors in different land types were researched in this study.Samples were collected from four types of land in Saihan District,Hohhot,Inner Mongolia,respectively,including green land,botanical garden,cultivated land and wasteland.The results showed that main types of microbe in the four different types land were bacteria,fungi and actinomyces.Among them,proportion of actinomycetes was the largest,followed by bacteria and fungi.Microbial community characteristics were affected by sampling depth,temperature,land types and moisture content.With the increase of sampling depth,the quantity of microorganism in soils of four-type land continuously decreased,and the total quantity of microorganism in 0-10 cm layer was the largest.Among four-type land,the amount of soil microorganism in wasteland was the largest.It was because the wasteland contained more organic matter,which provided nutrients for the growth of microorganism.Too high or too low moisture content was not conducive to the growth of microorganism.Only when the moisture content was optimum,the quantity of microorganism was the largest.For green land and botanical garden,the optimum moisture content was 10%-15%,the optimum moisture content of cultivated land was 15%-20%,and the optimum moisture content of wasteland was about 10%.