干旱区研究 ›› 2014, Vol. 31 ›› Issue (4): 702-708.

• 土壤生态 • 上一篇    下一篇

土壤侵蚀对土壤理化性质及土壤微生物的影响

  

  1. (1.河南省科学院地理研究所,河南 郑州 450052; 2.中国科学院生态环境研究中心,城市与区域生态国家重点实验室,北京 100085; 3.中国科学院地理科学与资源研究所,生态系统网络观测与模拟重点实验室,北京 100101)
  • 收稿日期:2013-02-01 修回日期:2013-04-15 出版日期:2014-07-15 发布日期:2014-08-11
  • 作者简介:胡婵娟(1981-),女,博士,助理研究员,主要从事土壤微生物和植被恢复方面的研究.E-mail: huchanjuan1981@126.com
  • 基金资助:

    国家自然科学基金项目(41371123)

Effects of Soil Erosion on Soil Physicochemical Properties and Soil Microorganisms

  • Received:2013-02-01 Revised:2013-04-15 Online:2014-07-15 Published:2014-08-11

摘要: 通过对黄土丘陵沟壑区侵蚀环境下4种典型坡面上坡顶、坡肩、坡背、坡脚和坡趾5个不同地形部位137Cs的含量、土壤理化性质及土壤微生物指标的测定和分析。结果表明:用来表征土壤侵蚀程度的137Cs含量与土壤有机碳、全氮、土壤容重、电导率、土壤微生物功能多样性及细菌菌群之间均存在显著的回归关系,土壤有机碳、全氮及土壤容重随着137Cs含量的增加呈增加趋势,土壤电导率、土壤微生物功能多样性呈下降趋势,而土壤细菌呈先下降后增加的趋势。土壤侵蚀过程能够直接影响土壤养分在坡面上的空间分布及土壤结构,通过影响土壤性质,改变土壤微生物群落的生长环境和营养物质的含量,从而影响土壤微生物的生长。

Abstract: Soil erosion is a serious problem in the Loess Plateau. It reduces soil productivity, causes irreversible soil and soil nutrient loss. Although many studies about the effects of soil erosion on soil nutrients, sediments and runoff have been done, the quantificational research on the relationship between soil erosion and soil nutrients, especially with soil microorganisms, was limited. In this study, the 137Cs tracer method was used to research the relationship between soil erosion with soil physicochemical properties and soil microorganisms in erosion environment in the hilly area of the Loess Plateau. The experiment was conducted in the Yangjuangou Valley located near Ya[JP8]n’[JP]an City in north Shaanxi Province, China. Four typical hill slopes including F (artificial forest), G (grass), GFG (grass on upper and lower slopes and artificial forest on middle slope) and FGF (artificial forest on upper and lower slopes and grass on middle slope) were chosen. On each of the four slopes, soil sampling sites were distributed on the summit, shoulder, backslope, footslope and toeslope along the hillslopes. Soil samples were collected in August 2007 for analyzing of the concentration of 137Cs which could indicate soil erosion degree, soil physicochemical properties including the soil organic carbon content, total soil nitrogen content, soil bulk density, electrical conductivity, pH value, soil water content and soil microbial properties including soil microbial carbon, soil microbial functional diversity and soil microbial community structure. The results showed that the concentration of 137Cs varied significantly between different slope positions, and the distribution of 137Cs along hillslope was different under four vegetation patterns. There was a significant regression relationship among soil organic carbon content, total soil nitrogen content, soil bulk density, electrical conductivity and 137Cs concentration.Soil organic carbon content, total soil nitrogen content and bulk density were increased with the increase of 137Cs concentration but the decrease of electrical conductivity. There was no significant correlation between the soil water content and pH value and the concentration of 137Cs. There was no direct impact of soil erosion on soil microbial biomass and neither the significant relationship between 137Cs concentration and soil microbial biomass. However, the regression analysis indicated that soil erosion could affect significantly soil microbial diversity and soil microbial community. Soil microbial functional diversity was decreased, and soil bacterial biomass was decreased at first and then increased with the increase of 137Cs concentration. In conclusion, soil erosion could directly impact the distribution of soil nutrients and soil structure on slope.