【摘要】 为了比较桉树纯林和桉-珍混交林的水土流失规律,在广西南宁市郊的马尾松林采伐迹地同一坡面上,分别营造桉树纯林(EP)和桉-珍混交林(EM)两种人工林模式,各建造径流场3个,进行水土及其养分流失量的监测研究。结果表明:EP、EM年平均地表径流量分别为181.7、182.6 m3/hm2;年平均泥沙流失量分别为995、1 004 kg/hm2;年平均侵蚀模数分别为99.5、100.4 t/km2;年平均养分(N、P、K)流失量分别为0.109、0.110 kg/hm2。EP、EM水土及养分流失量的季节变化较一致,为夏季(77.2%~80.0%)>秋季(18.8%~19.6%)>春季(1.2%~3.2%)>冬季(0.0%)。1~3年生桉树纯林和桉-珍混交林两种人工林模式各项水土流失特征量比较接近,两者的水土及养分流失量比较小,而且无显著差异(t<0.05)。更多还原

【Abstract】 To compare the regularities of soil and water erosion of Eucalyptus gradis pure stand( EP)and Eucalyptus gradis-precious hardwood mixed stand( EM),we constructed these two plantations in the same slope direction of the Pinus massoniana cutting blank in the south of Nanning,Guangxi. Basing on the 3 runoff plots of each plantation,we monitored the soil erosion and nutrient loss of these two plantations. The results showed that there was 181. 7 m3/hm2 and 182. 6 m3/hm2 of average annual surface runoff,995 kg/hm2 and 1 004 kg/hm2 of average annual soil loss,99. 5 t/km2 and 100. 4 t/km2 of annual erosion modulus,0. 109 kg/hm2 and 0. 110 kg/hm2 of average annual N,P,and K nutrients loss in EP and EM,respectively. The amount of soil erosion and nutrient loss had a similar change in seasons both in EP and EM,the amount of soil erosion and nutrient loss follows the order of summer( 77. 2% ~80. 0%) > autumn( 18. 8% ~ 19. 6%) > spring( 1. 2% ~ 3. 2%) > winter( 0. 0%). The charac-teristics of soil and water conservation from 1 to 3 years old Eucalyptus gradis pure stand were closed to Eucalyptus gradis-precious hardwood mixed stand,the amount of soil erosion and nutrient loss was small and there was no significant difference( t < 0. 05).更多还原