摘要
以分布于共和盆地沙区小叶锦鸡儿人工固沙植被下土壤为研究对象,采用尼龙网袋法模拟凋落物的自然分解,应用微生物传统培养方法研究其微生物组成和数量,并测定土壤组成及养分含量.结果表明:随植被恢复时间延长和凋落物的分解天数的增加,土壤微生物均以细菌为主,所有处理植被恢复区的土壤细菌、真菌、放线菌和微生物总数均高于流动沙地,且随植被恢复年限延长,土壤细菌、真菌、放线菌和微生物总量总体上均呈增加趋势,随着凋落物分解时间的延长,土壤细菌、真菌、放线菌和微生物总量均呈先增加后降低的趋势;土壤的粘粉粒含量逐渐增加,有机质、全氮、速效氮、速效磷、速效钾含量也逐渐增加;林龄和凋落物降解对微生物均有显著影响,其中林龄是影响土壤微生物数量最重要的因素,凋落物降解是影响微生物组成的最重要因素.研究区的治沙模式促进了土壤微生物数量的积累,有利于生态系统的植被恢复和可持续发展.
Abstract
This study focused on the soil beneath the artificially-fixed sand vegetation of Caragana mi-crophylla in the sandy area of Gonghe Basin.The nylon mesh bag method was employed to simulate the natural degradation of litter,and traditional microbial culture methods were used to investigate the microbial composi-tion and quantity.Additionally,soil composition and nutrient content were measured.The results revealed that with the prolongation of vegetation restoration time and the increase in litter decomposition days,bacteria re-mained the dominant microbial population in the soil.The total numbers of soil bacteria,fungi,actinomycetes,and microorganisms in all vegetation restoration areas were higher than those in the mobile sandy land.Overall,the total numbers of soil bacteria,fungi,actinomycetes,and microorganisms increased with the extension of vegetation restoration years.As the decomposition time of litter prolonged,the total numbers of soil bacteria,fungi,actinomycetes,and microorganisms initially increased and then decreased.Additionally,the content of soil clay and silt particles gradually increased,along with the contents of organic matter,total nitro-gen,available nitrogen,available phosphorus,and available potassium.Both forest age and litter degradation had significant impacts on microorganisms.Among them,forest age was the most important factor influencing the quantity of soil microorganisms,while litter degradation was the most significant factor affecting microbial composition.The sand control model in the study area facilitates the accumulation of soil microbial popula-tions,which is beneficial for vegetation restoration and sustainable development of the ecosystem.
基金项目
中央财政林业科技推广示范项目(青[2023]TG11)
NETL
NSTL
万方数据