毛乌素沙地4种固沙植物根际与非根际土壤生物学特性

Rhizosphere and Non-rhizosphere Soil Biological Properties of Four Kinds of Sand-Fixing Plants in the Mu Us Sandland

以毛乌素沙地柠条、沙柳、沙蒿、沙地柏4种固沙植物为研究对象,对其根际与非根际土壤微生物数量、酶活性进行研究,并分析其与土壤养分含量的相关性。结果表明:细菌在4种植物根际与非根际土壤微生物群落中均占绝对优势,土壤微生物数量与土壤酶活性均表现出根际聚集现象;4种植物根际与非根际土壤真菌、蔗糖酶、碱性磷酸酶、脲酶与土壤养分含量均呈显著正相关;根际土壤肥力水平综合得分总体上大于非根际土壤,4种固沙植物根际与非根际土壤肥力水平综合得分表现为:柠条﹥沙柳﹥沙蒿﹥沙地柏。从土壤生物学特性角度考虑,沙区应优先选择柠条作为固沙植物;土壤有机质、碱解氮、速效磷、速效钾在评价4种固沙植物根际与非根际土壤肥力中起重要作用,而真菌、碱性磷酸酶是首选的土壤微生物指标和土壤酶指标。

Taking four kinds of sand-fixing plants,eg. Caragana korshinskii,Salix psammophila,Artemisia desterorum and Sabina vulgaris as tested object in the Mu Us Sandland. The soil microorganism quantity,soil enzyme activities and their relationships in rhizosphere and non-rhizosphere soil of the four species were studied. The results showed that bacteria dominated in soil microbial community in the rhizosphere and non-rhizosphere soils of four kinds of plants,the number of soil microorganisms and enzyme activities presented obvious rhizosphere aggregation.The significant relationships appeared among fungi,soil sucrase,phosphatases,urease activities and nutrient factors. The comprehensive fertility level of the rhizosphere soil was higher than that of non-rhizosphere soil,and that of rhizosphere and non-rhizosphere soil was in the order of C. korshinskii > S. psammophila > A. desterorum >S. vulgaris. The most suitable cultivation species for the construction of sand-fixing plants in Mu Us sandland is C. korshinskii. Soil organic matter content,available N,available P,available K played important roles in fertility level evaluation of rhizosphere and non-rhizosphere soil of four kinds of sand-fixing plants,and soil fungi and phosphatases could be the preferred soil microorganism and soil enzyme indicator.