半干旱区流域土壤养分分布特征及其与地形、植被的关系  

Soil nutrients distribution and its relation to landform and vegetation at small watershed in semiarid area

作　　者：郭胜利[1] 刘文兆[1] 史竹叶[1] 侯喜禄[1] 李凤民[2] 

机构地区：[1]中国科学院水利部水土保持研究所 [2]兰州大学生命科学学院,甘肃兰州730000

出　　处：《干旱地区农业研究》2003年第4期40-43,共4页Agricultural Research in the Arid Areas

基　　金：973"预研究项目"半干旱黄土区植被景观覆盖与农业生态系统功能调控";国家自然科学基金项目(90202011)资助

摘　　要：以小流域为单元,以典型横断面为代表,初步分析了黄土高原半干旱区中连川小流域坡顶、坡面和坡脚不同部位土壤养分分布特征及其与地形和植被的关系。结果表明,中连川流域土壤养分全量和速效态都匮乏。在开垦利用条件下,0～20cm土层土壤有机碳、氮、磷、Olsen-P、硝态氮含量在不同坡位的高低顺序:坡面<坡顶<坡脚,显示了土壤养分坡脚富集、坡面和坡顶流失的特征。恢复地表植被后,土壤有机碳、氮的含量较相邻的农田显著提高。草本植被群落对土壤养分(0～20cm)的积累促进作用高于灌木。The study was conducted to investigate soil nutrients distribution and its relation to landform and vegetation along summit to toeslope transection at the small watershed of Zhonglianchuan in the semiarid hilly region of Loess Plateau. The results showed that both soil nutrients and available fractions were significantly low across the watershed. Under the condition of cultivation, soil organic carbon (SOC), total soil nitrogen (TSN), total soil phosphorus (TSP), OlsenP, and nitrate N in the 0~20 cm depth were low at slopeback and summit, and enriched at toeslope due to soil losses. The distribution of soil nutrients could be put in order as: slopeback < summit < toeslope. SOC and TSN in the 0~20 cm depth were increased significantly when the cropland was converted into grassland. Herbaceous plants caused more accumulation of soil nutrients than shrubby plants.

关 键 词：黄土高原半干旱区 流域 土壤养分 分布特征 地形 植被 

分 类 号：S158.3[农业科学—土壤学]