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结合全国第二次土壤普查的数据和野外试验,分析了嫩江流域近20a的土壤质量变化。研究结果表明,经过近20a的演化,土壤的质地发生变化,土壤中粉粒成分占近50%,基本没有变化,砂粒和黏粒的百分比发生变化,砂粒减少了22.95%,黏粒增加了50.09%。土壤质地主要以黏壤土和黏土为主,所占面积百分比分别为32.52%和66.51%。流域内壤土所占比例下降了17.54%,黏壤土和黏土分别增长了9.34%和8.20%。嫩江流域土壤中的有机质含量范围0.55%～12.26%,与普查数据比较呈下降趋势,下游开发地区的土壤中有机质含量下降趋势明显,上游有机质含量增加了27.14%,下游有机质含量减少了33.11%。嫩江流域未开发地区的土壤总体上未呈现严重的沙化趋势,但是嫩江下游的土壤沙化程度较上游严重,有机质的变化在流域空间分布上表现出明显的不同。
Combined with the data of the second national soil survey and field experiments, the soil quality changes of the Nenjiang River Basin in recent 20 years were analyzed. The results showed that after nearly 20 years of evolution, the texture of soil changed, the content of powder and granule accounted for nearly 50% in the soil, the percentage of sand and clay changed, the amount of sand reduced by 22.95% and the amount of clay increased by 50.09 %. Soil texture is dominated by clay loam and clay, accounting for 32.52% and 66.51% of the total area, respectively. The proportion of loam in the basin decreased by 17.54% and that of clay loam and clay increased by 9.34% and 8.20% respectively. The content of organic matter in the soil of Nenjiang River Basin ranged from 0.55% to 12.26%, showing a decreasing trend compared with the census data. The content of organic matter in the soil in the downstream development area decreased obviously. The content of organic matter in the upper reaches increased by 27.14% and the content of organic matter in the lower reaches decreased by 33.11%. The soil in the undeveloped areas of Nenjiang River Basin did not show a serious trend of desertification in general, but the degree of soil desertification in the lower reaches of Nenjiang River was more serious than that in the upper reaches of the Nenjiang River. The change of organic matter showed obvious differences in the spatial distribution of the watershed.