【摘要】 PAM(聚丙烯酰胺 )作为一种土壤结构改良剂施用于地表 ,能显著的减小径流和土壤侵蚀量。本研究设计了一系列人工降雨模拟试验 ,定量研究了坡度、坡长、PAM覆盖度、雨强对陡坡耕地土壤侵蚀产沙的影响。试验采用三种雨强 :5 0mmh- 1 、10 0mmh- 1 、15 0mmh- 1 ,四种坡度 :5°、10°、2 0°、2 5° (8 74%、17 63 %、3 6 4%、46 63 % ) ,四种当量坡长 :8m、16m、2 4m、40m ,五种地表处理 :对照、麦草覆盖、三种PAM覆盖度A、B、C(A <B <C)。通过侵蚀产沙试验结果 ,鉴别了不同坡度、PAM覆盖度、雨强条件下陡坡耕地无土壤侵蚀的临界坡长。结果表明 ,PAM能显著地减少土壤侵蚀产沙量 ,延长陡坡耕地的临界坡长更多还原

【Abstract】 Polyacrylamide (PAM), as a new effective soil amendment, applied on to soil surf ace, can signifi cantly reduce runoff and erosion. With a series of rainfall simulation tests, ef f ects of slope degree, slope length, PAM coverage and rain intensity on soil sedi ment loss of steep cultivated slope land are approached. The experiment is desi g ned to have 3 levels of rain intensity: 50 mm h -1 , 100 mm h -1 and 1 50 mm h -1 ; 4 slope degree: 5°, 10°, 20°and 25° (8.74%, 17.63%, 36.4% a nd 46.63%); 4 equivalent slope length: 8 m, 16 m, 24 m and 40 m; and 5 treat ments: control, straw coverage, 3 PAM coverage-A, B and C(A<B<C). Based on the experiment resul ts, the critical slope length for soil erosion on steep cultivated slope land is de termined. The results show that PAM can significantly reduce the amount of sedi m ent loss, and lengthen the critical slope length on steep cultivated slope land .更多还原