为了探讨围封与放牧措施下生物土壤结皮发育及其与微生境土壤养分的对应关系,本研究以黄土高原天然草地两类生物土壤结皮(藻类和藓类)为研究对象,调查了生物土壤结皮发育的形态指标,并就不同措施下生物土壤结皮层及其下层土壤养分特征进行了比较分析。结果表明,两类生物土壤结皮对围封与放牧干扰的响应一致,盖度均表现为围封显著高于放牧,而厚度和生物量无显著差异。然而,围封与放牧对生物土壤结皮层及其结皮下层养分含量的影响不尽相同,围封藻结皮层及其结皮下层SOC,TN和Zn含量显著高于放牧,而TP和Na则显著低于放牧。另外,生物土壤结皮层与结皮下层养分间的关系均存在差异,其藻结皮层土壤SOC与TN,TP,Na,K,Fe,Mn和Zn均呈正相关,与Ca呈负相关;藓结皮层SOC分别与Mn和Zn呈正相关,而与Ca和Fe呈负相关。
In order to explore the relationships between the development of biological soil crusts and soil nutrient characteristics of its microhabitat under fenced and grazed, this study selected two kinds of biological soil crusts in the natural grassland of the Loess Plateau as the research objects to investigate the morphological indexes of biological soil crusts. Meanwhile, the soil nutrients characteristics of different types biological soil crusts layer and the under crusts had been analyzed and compared. The results indicated that The response of the development of different soil crusts to fenced and grazed disturbance was consistent. It showed the coverage in fenced plot was significantly higher than that in the grazed, and the thickness and biomass had no significant difference. However, the SOC, TN and Zn contents of algae cortex soil and the subcutaneous layer in the fenced were significantly higher than that in the grazed, and the contents of TP and Na in the fenced were significantly lower than that in the grazed. In addition, fenced or grazed, there was a positive correlation relationships between the algae cortex SOC and TN, TP, Na, K, Fe, Mn and Zn, respectively; but negatively correlated with Ca; moss cortex Mn and Zn were positively correlated with SOC. but negatively related with Ca and Fe.