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Heidi Wienert George Roy C. Sidle 《Journal of the American Water Resources Association》1995,31(6):1051-1062
ABSTRACT: Geomorphic processes may partly determine channel geometry. Soil particle uplift during freezing and thawing cycles and bank sloughing during wetting and drying periods were observed. Soil properties and channel dimension were measured to determine the dominant processes controlling channel geometry in eight small (mean area 0.096 km2) drainages in Logan Canyon, Utah. Soil cohesion was low (plasticity index > 15) for all but one of the drainages sampled. Basin scale geomorphic variables were examined to determine if they control channel dimension. Bankfull width was highly correlated to channel length and valley length with r2 values of 0.85 and 0.84, respectively. A strong canonical correlation (0.64) showed that distance from the watershed divide, bank liquid limit, and bank sand content were effective predictor variables of bankfull width and depth. The interrelations between geomorphic and pedogenic processes were the strongest determinants of ephemeral channel dimension in this study. 相似文献
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皆伐作业对林地土壤因子的影响 总被引:5,自引:0,他引:5
对福建省永安市元沙林业采育场杉阔混交人工林林地皆伐作业前后土壤理化性质变化进行试验研究.结果表明,皆伐作业使林地土壤许多理化性质发生改变.皆伐导致土壤容重增大0.13 g·cm-3,土壤结构体破坏率提高12.50%,最大持水量下降6.65%,总孔隙度减小3.88%; 同时土壤主要化学性质,如有机质、全N、水解性N、全P、速效P、全K、速效K等普遍降低,它们的含量分别下降8.14 g·kg-1、0.18 g·kg-1、7.20 mg·kg-1、0.38 g·kg-1、39.98 mg·kg-1、6.95 g·kg-1和12.31 mg·kg-1; 此外,对皆伐作业造成土壤理化性质变化的原因进行了分析,并从森林生态采运角度出发,提出减少皆伐作业对林地土壤破坏的技术措施. 相似文献
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