通过对不同健康状况(健康、中度枯梢、重度枯梢或死亡)刺槐林的生态调查、林下土壤采样,分析了不同健康林地不同采样深度(0~260 cm)的土壤属性差异性及变化特征.研究结果表明:(1)土壤水分和盐分含量在不同健康状况刺槐林地间存在显著的差异,且随着刺槐林退化程度的加深,土壤水分、盐分、粘粒含量和容重显著地增加;(2)在相同健康状况林地的不同土层间,只有土壤颗粒含量存在显著性的差异;(3)随着采样深度的增加,土壤颗粒显著变粗,土壤水分则显著地减少(在健康林地)或增加(在重度枯梢林地),土壤盐分则具有明显的表聚性.采用典范对应分析方法进行分析,发现刺槐林的健康属性与土壤属性相关性大,且土壤水分和盐分是影响刺槐林健康状况的最重要的土壤属性因素;由地下水位抬升而导致的土壤含水量增加是刺槐林退化的最重要因素.%The soil properties of Robinia pseudoacacia forests with different health statuses (health,medium dieback,and severe dieback or death)in the Yellow River delta were studied through ecological survey and soil layer (0~260 cm)sampling based on canonical correspondence analysis (CCA). The results indicated that there were significant differences in soil moisture and salinity contents among R. pseudoacacia forests with different health statuses,and the soil moisture,salinity and clay particle contents,as well as the soil bulk density increased significantly with the continuous degradation of R. pseudoacacia forest. There was a significant difference only in soil particle content among different soil layers of R. pseudoacacia forest with the same health status. Along with the increase in soil layer depth,the soil particle size was significantly increased,while the soil moisture content was significantly reduced (in healthy forest land)or increased (in severe dieback forest land). The soil salinity was obviously ac-cumulated in the topsoil. The canonical correspondence analysis showed that the health status of R. pseudoacacia forest was well correlated with the soil properties,and soil moisture and soil salinity were the most important soil property factors affecting the health status of R. pseudoacacia forest. The increase in soil moisture content caused by the upraising of underground water level was the most important cause for the degradation of R. pseudoacacia forest.
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