共和盆地不同灌木群落生物土壤结皮理化性质差异

Differences in the physical and chemical properties of biological soil crusts in different shrub communities in the Gonghe Basin

探究青海共和盆地不同灌木群落生物土壤结皮(Biological Soil Crusts,BSCs)理化性质差异,为加强生物土壤结皮资源的保护与合理利用提供理论参考。选取共和盆地沙蒿(Artemisia desertorum)、小叶锦鸡儿(Caragana microphylla)和乌柳(Salix cheilophila)群落中不同发育阶段的生物土壤结皮为研究对象,野外取样结合室内分析,研究其颗粒组成及养分特征。结果表明:三种灌木群落生物土壤结皮的颗粒组成均以沙粒为主(45%~90%),其中,小叶锦鸡儿沙粒含量>乌柳>沙蒿,且其含量均显著低于灌丛间裸沙。乌柳群落生物土壤结皮全氮、全碳、有机质、有效磷、速效钾、碱解氮、全磷含量均显著高于沙蒿、小叶锦鸡儿群落,且随生物土壤结皮发育,各含量在三种灌木群落中呈增加趋势。灌木群落对生物土壤结皮理化性质的影响程度最高,且灌木生物量与生物土壤结皮盖度、厚度、全氮、全碳、有机质、有效磷、速效钾、碱解氮、全磷呈显著正相关,与沙粒含量呈显著负相关(P<0.05)。灌木群落有效改良共和盆地沙地生物土壤结皮土壤结构,沙蒿群落更有利于土壤的细化,乌柳群落更有利于养分蓄积。

Exploring the differences in the physical and chemical properties of biological soil crusts(BSCs)in different shrub communities in the Gonghe Basin of Qinghai Province to provide theoretical reference for the protection and rational utilization of BSCs resources.The BSCs at different stages of Artemisia desertorum,Caragana microphylla,Salix cheilophila communities in the Gonghe Basin were investigated.Particle composition and nutrient characteristics were studied through field sampling and indoor analysis.The results showed that the particle composition of BSCs in the three shrub communities was dominated by sand(45%–90%).The sand content of Caragana microphylla>Salix cheilophila>Artemisia desertorum was significantly higher than that of bare sand between shrubs.The contents of total nitrogen,total carbon,organic matter,available phosphorus,available potassium,alkali-hydrolyzable nitrogen,total phosphorus in the BSCs of the Salix cheilophila community were significantly higher than other,and the contents increased with the development of BSCs in the three shrub communities.The shrub community mostly influenced the physical and chemical properties of BSCs,and the shrub biomass was significantly positively correlated with the coverage,thickness,total nitrogen,total carbon,organic matter,available phosphorus,available potassium,available nitrogen,and total phosphorus of BSCs,and significantly negatively correlated with sand content(P<0.05).The shrub community effectively improved the soil structure of BSCs in the sandy land of the Gonghe Basin.The Artemisia desertorum community was more conducive to soil refinement,and the Salix cheilophila community was more conducive to nutrient accumulation.