摘要
采取时空互代法,以黄土丘陵区不同林龄的人工刺槐林为研究对象,选取坡耕地为对照,分析土壤抗蚀性的变化过程,并在此基础上提出土壤抗蚀指数。结果表明,黄土丘陵区坡耕地种植刺槐林后:>0.25 mm土壤水稳性团聚体、>0.5 mm土壤水稳性团聚体、平均质量直径、有机碳含量较坡耕地显著增加,并随林龄增加逐渐升高;土壤团聚状况、团聚度显著高于坡耕地并随林龄增加先降低后升高;土壤结构破坏率、分散系数和分散率呈波动式降低;小粒径的微团聚体和机械组成逐步向大粒径转变。相关性分析表明:>0.25 mm土壤水稳性团聚体、>0.5 mm土壤水稳性团聚体、平均质量直径、有机碳与全氮、碱解氮、速效钾、全磷呈显著正相关(P<0.05),与土壤密度呈显著负相关;结构破坏率、分散系数和分散率则与全氮、碱解氮、全磷呈显著负相关;团聚状况、团聚度与全氮、全磷呈显著正相关。土壤抗蚀指数随人工刺槐林林龄的增加而显著升高,可以全面、客观地反映土壤抗蚀性能的演变过程。侵蚀环境下的坡耕地由于受到人为活动的干扰,土壤抗蚀性较差,种植刺槐林后,土壤抗蚀性显著增强。
In order to reveal the effects of plantation on soil anti-erodibility, Robinia pseudoacacia plantation at different ages in Hilly-gully region of Loess Plateau was chosen to analyze the changes of soil anti-erodibility, and the slope cropland was used as contrasts. The results indicate that the contents of 〉0.25 mm soil water-stable aggregates, 〉 0. 5 mm soil water-stable aggregates, mean weight diameter and organic C increase significantly compared with slope cropland and increase with ages. Aggregate state and aggregate degree are improved markedly compared with slope cropland and declined firstly then raised with increasing of ages. Ratio of soil structure deterioration, dispersive rate and disporsive coefficient take on wavelike drop. Small microaggregates and mechanical composition transform into ones with much bigger diameter. Results of correlation analysis shows that the 〉 0.25 mm soil water-stable aggregates, 〉 0.5 mm soil water-stable aggregates, mean weight diameter and organic C positively correlated with N, available N, available K and total P（P 〈 0.05） , but negative with soil density. High negative correlation is observed between ratio of structure deteriorative, dispersive rate, dispersive coefficient and total N, available N, total P. Soil anti-erodibility index（1）rise with increase of ages and can generally reflect the change of soil anti-erodibility. It can be concluded that the poor soil anti-erodibility of slope cropland under erosive environment owing to human cultivation activities is improved greatly by plantation.
出处
《中国水土保持科学》
CSCD
2010年第2期1-7,共7页
Science of Soil and Water Conservation
基金
国家重点基础研究发展规划项目“水土流失环境效应评论理论与指标体系”(2007CB407205)
中国科学院西部行动计划项目“黄土高原水土保持与可持续生态建设试验示范研究”(KZCX2-XB2-05)
国家自然科学基金“黄土丘陵区自然植被演替过程根际微生物响应及其效应分析”(40801094)
关键词
人工刺槐林
土壤抗蚀性
土壤抗蚀指数
黄土丘陵区
Robinia pseudoacacia L. plantation
soil anti-erodibility
soil anti-erodibility index
Hillygully region of Loess Plateau
