关键词: 土壤侵蚀, 137Cs, 经济林营造, 相关性分析

Abstract: Soil erosion has always been a hot topic. In order to explore the correlation between soil erosion and various soil physical and chemical properties, this paper used 137Cs nuclear tracer technology to sample and analyze 4 kinds of forests, including coniferous and broad-leaved mixed forest (CBF), hawthorn forest (HF), apple forest (AF) and chestnut forest(CF), transformed from coniferous and broad-leaved mixed forest in Ganyu District, and conducted quantitative evaluation on the soil erosion characteristics in this area. The results showed that: ① The soil 137Cs content of CBF was 546.92 Bq/m2, and building of economic forest had reduced the soil 137Cs content. The thickness of annual soil loss in CBF was 0.79 mm. The average annual soil loss thickness of AF, HF and CF were 2.92 times, 2.33 times and 1.10 times of that of CBF. ② There was extreme significant positive correlation between soil 137Cs in research area and soil total nitrogen and soil organic carbon (P<0.01), and also significant positive correlation with soil carbon and nitrogen ratio (P<0.05). While, there was no significant correlation with the other soil physical and chemical properties. Soil 137Cs showed an extremely significant positive correlation with the organic carbon content of aggregates with grain size <0.25 mm, 0.25~0.5 mm and 0.5~1 mm (P<0.01), and a significant positive correlation with the organic carbon content of aggregates with grain size >1 mm (P<0.05). The building of economic forest had enabled the changes in land utilization type, affected soil erosion, and at the same time also affected soil nutrient index and aggregate organic carbon in different land utilization types.

Key words: soil erosion, 137Cs, economic forest construction, correlation analysis