Zhang Pei-Pei, Zhao Yun-Ge, Wang Yuan, Yao Chun-Zhu
Ying Yong Sheng Tai Xue Bao. 2014 Mar;25(3):657-63.
By using water drop penetration time (WDPT) and molarity of ethanol droplet (MED) methods, the soil water repellence of undisturbed biological soil crusts (biocrusts) in five successional stages, from the hilly Loess Plateau region of China was tested. The five stages of biocrusts were light cyanobacterial crust, dark cyanobacterial crust, cyanobacterial with sparse moss crust, moss and tiny cyanobacteria patches crust and moss dominated crust. The results showed that 1) the soil water repellence was markedly increased both in the intensity and persistence since the formation of biocrusts. 2) The soil water repellence showed a decrease trend along with the successional stages of biocrusts. The soil water repellence of the biocrusts with the moss coverage above 20% was significantly lower than that of the cyanobacterial crusts. 3) The soil water repellence of the biocrusts was closely related to soil moisture and the dominant organism. The soil water repellence increased with the decrease of soil water content for the moss dominated biocrusts, while changed in a bimodal curve with the decrease of soil water content for the cyanobacterial biocrusts.
采用水滴穿透时间（WDPT）和乙醇液滴摩尔浓度（MED）方法，对中国黄土高原丘陵区五个演替阶段的原状生物土壤结皮（生物结皮）的土壤斥水性进行了测试。生物结皮的五个阶段分别为浅色蓝藻结皮、深色蓝藻结皮、蓝藻与稀疏苔藓结皮、苔藓与微小蓝藻斑块结皮以及苔藓主导结皮。结果表明：1）自生物结皮形成以来，土壤斥水性在强度和持久性方面均显著增加。2）土壤斥水性随生物结皮的演替阶段呈下降趋势。苔藓覆盖率高于20%的生物结皮的土壤斥水性显著低于蓝藻结皮。3）生物结皮的土壤斥水性与土壤湿度和优势生物密切相关。苔藓主导的生物结皮的土壤斥水性随土壤含水量的降低而增加，而蓝藻生物结皮的土壤斥水性随土壤含水量的降低呈双峰曲线变化。
