泥石流频发区土壤有机质空间变异特征

利用GPS定位技术在泥石流频发区——云南东川蒋家沟流域采集土样99个,研究土壤有机质空间变异特征.结果表明：1）流域土壤有机质的平均质量分数（2.21 g/kg）较低;2）土壤有机质在空间分布上有明显的各向异性,空间变异特征主要反映在东北-西南方位,空间展布呈条带状;3）土壤有机质的空间变异存在中等程度的空间相关性,是由结构性因素和随机性因素共同作用引起的,受土壤质地、坡度、高程、土地利用方式和人类生产活动等因素的影响;4）同一因素不同级别下,土壤有机质质量分数差异极显著.研究结果可以为泥石流流域碳储量的估算提供依据,为土壤侵蚀退化地的生态恢复与重建提供参考.

Spatial characteristics of soil organic content in a frequent debris flow area

Ninety-nine soil samples （GPS used for recording sample location） were collected in the Jiangjiagou Ravine,Yunnan Province,China,a frequent debris flow occurring area,in order to statistically investigate the spatial variation characteristics of soil organic matters.The results indicated that the average content of soil organic matters （2.21 g/kg） was at a low level.The soil organic matters in space presented an obvious anisotropy,and spatial variation characteristics mainly existed in the northeast-southwest direction with the strip shape.The spatial variability of soil organic matters was controlled by both its auto-spatial dependence and random factors,and the soil organic matters displayed medium degree of spatial correlation.Furthermore,the distribution of soil organic matters was influenced by soil texture,slope,elevation,land use types and human production activities.Under different levels of a certain factor,the soil organic content showed extremely significant difference.The results can provide a basis for carbon reserves estimation in debris flow ravine,and the reference for ecological restoration and reconstruction in the area with soil erosion degradation.