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在2002年开展的川中丘陵区武家沟小流域泥沙来源的调查中, 137Cs和210Pb双同位素示踪法得到了应用, 流域内陡坡林地、缓坡农台地和裸坡地表层土壤的137Cs和210Pb平均含量分别为(7.15±0.40)和(162.01±3.86) Bq·kg-1; (4.01±0.31)和(70.96±2.65) Bq·kg-1; 0和(15.12±1.22) Bq·kg-1. 近期水库淤积泥沙的137Cs和210Pb含量分别为(3.06±0.23)和(72.66±1.61) Bq·kg-1. 运用混合模型求得林地、农地和裸坡地(含沟岸)的相对来沙量分别为18%, 46%和36%. 农台地和裸坡地(含沟岸)是流域内最重要和次重要的泥沙来源. 根据1956年以来水库的泥沙淤积量, 流域输沙模数为642 t·(km2·a)-1, 占流域面积约2/3的林地和1/3的农地的侵蚀模数分别为173和886 t·(km2·a)-1.
In the survey of sediment source of Wujiagou small watershed in central Sichuan hilly region in 2002, 137Cs and 210Pb double isotope tracing methods were applied. The average content of 137Cs and 210Pb in steep slope woodland, gentle slope farmland and bare slope surface soil in the basin, (7.15 ± 0.40) and (162.01 ± 3.86) Bq · kg-1, (4.01 ± 0.31) and (70.96 ± 2.65) Bq · kg-1 and 0 and (15.12 ± 1.22) Bq · kg- The 137Cs and 210Pb contents of sediment in reservoirs were (3.06 ± 0.23) and (72.66 ± 1.61) Bq · kg-1, respectively, and the relative sediment concentrations of woodland, agricultural land and bare slope land Respectively, 18%, 46% and 36% .Narit platform and bare slope (including ditches) are the most important and important sediment sources in the basin.According to the amount of sediment in the reservoir since 1956, (Km2 · a) -1 and 642 t · (km2 · a) -1 respectively, and the erosion modulus of forestland and 1/3 of farmland, accounting for about two thirds of the drainage area, were 173 and 886 t · (km2 · a) -1, respectively.