【摘要】 【目的】探究影响植被分布状况的土壤环境,揭示荒漠河岸植被盖度空间变化规律与土壤因子的相关关系.【方法】以石羊河下游荒漠植被河岸带为研究对象,结合野外调查与数理统计的方法,考察了距河岸500 m范围内的植被盖度变化规律,并分析了土壤含水率、土壤养分与灌木、草本及总盖度之间的关系.【结果】石羊河下游河岸带荒漠植被中,河岸间距与植被总盖度、草本植被盖度呈负指数相关,与灌木呈二次函数相关;由于植被根系作用,土壤含水率是影响植被总盖度和草本盖度的主要因子,且与40 cm深的土壤含水率变化规律显著相关;土壤有机质含量是影响灌木盖度和长势的主要因子,其含量随河岸间距的增大而减小,在250 m处达到最大;土壤综合状况是影响植被丰富度的主要因子,250～300 m处土壤综合状况最佳,植被种类最多、长势最好.【结论】草本、木本植被盖度空间变化规律对土壤因子的响应不同,可为石羊河下游河岸带植被的重建和河岸生态系统的修复提供科学的理论依据.更多还原

【Abstract】 【Objective】 In order to clarify the soil environment affecting the distribution of vegetation,and to reveal the relationship between spatial variation of vegetation cover and soil factors in desert riparian. 【Method】 The fields investigation and mathematical statistics were carried to study riparian desert vegetation in lower reaches of Shiyang River. The law of desert riparian vegetation spatial succession was revealed within the range of 500 m. The relationship between soil moisture,soil nutrient and the type,richness and coverage of vegetation were discussed. 【Result】 In the desert vegetation on the lower reaches of the Shiyang River,the riverbed spacing was negatively correlated with the total vegetation coverage and herb cover,which was related to the quadratic function of shrubs. Soil moisture content was the main factor affecting the total vegetation coverage and herbs coverage,in which the change law of soil moisture content at 40 cm depths was significantly correlated with the law of vegetation coverage and herbs coverage because of the function of root. Soil organic matter content was the main factor affecting shrub coverage and growth. The content of soil organic increased with the increase of distance with bank and the maximum showed at 250 m. Soil condition was the main factor affecting vegetation richness,in which the condition at the range of 250～300 m showed the best,so the vegetation species and the growth reached the maximum value. 【Conclusion】 The spatial variation of herbaceous and woody vegetation coverage has different responses to soil factors. The results of this study can provide a more scientific theoretical basis for the reconstruction of vegetation in the lower reaches of the Shiyang River and the restoration of riverside ecosystems.更多还原