摘要
在陕西神木县与内蒙古东胜市交界的饮马泉小流域,选择有代表性的坡面进行地形剖面和土壤层垂直方向的系统采样。每个样品进行了粒级、土壤质量含水量、土壤有机质测试。经数据的分析模拟,得以下结论:①土壤粒级构成和物理性粘粒含量特征,可以指示研究区土壤的沙化程度和演化趋向,其具有向西北更干旱粗化方向过渡的倾向。②土壤水分随地貌部位的变化规律比较明显,在峁坡顶部和上部,垂向上具有自上而下增加的趋势,而在峁坡下部和坡脚却正好相反。不论何种地貌部位都存在一个相近的土壤蒸发、渗漏、持水能力相对的平衡深度。③土壤的物理性粘粒含量与土壤的水肥关系密切,物理性粘粒含量相对高的土壤剖面,土壤的水肥组合效果较好。④土壤水肥质地的组合效果,丘陵顶部的最差,依次过渡到坡脚的组合效果最好。其进一步表明,地貌因素在土壤形成后的一系列熟化、退化、被侵蚀和沙化的演化过程中,地貌仍起着至关重要的作用。
The study aimed at the impacts of the different landforms on the soil physical composition,soil moisture content and soil fertility of the slope loess field under sand cover.The series of samples were collected at section planes and vertical soil layers,in Yinmaquan watershed located on the boundary between Shenmu County and Dongsheng City,where the slope field had the representations.The soil texture,gravimetric soil moisture content and organic matter content of the samples were measured.Based on the analysis of the data,conclusions were obtained: 1) The soil texture and physical clay granule content were indices to indicate the desertification degree and evolvement trend.The study area demonstrated a drier and coarser trend towards northwest.2) There were different evolution laws of soil moisture content with different landform positions.It increased vertically from the top to upside of hilly slope,but decreased from the downside to foot.Whatever position the landform had,there was a similar balanced depth existed for the soil to evaporate,infiltrate,leak and hold water.3) The physical clay granule content had closely relationship with the soil fertility and moisture content.The section planes with higher physical clay granule contents had richer soil fertility and more moisture content.4) Effects of the combination of water,fertilizer and organic matter became more effective from the top to the foot of slope field,indicating that landform always had significant impacts on the series of evolution processes such as soil mellowing processes,soil degradation,soil erosion and soil desertification.Furthermore,the results also highlighted the evolution of soil texture with the landforms and the vertical soil layers,and could indicate the process of soil desertification and materials sources.
出处
《地理科学》
CSCD
北大核心
2011年第2期178-183,共6页
Scientia Geographica Sinica
基金
中国科学院水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室基金项目(10501-230)资助
关键词
沙盖黄土丘陵
物理性粘粒
土壤含水量
有机质
坡地剖面
slope loess field under sand cover
physical clay granule
soil moisture content
organic matter
section plane in slope field