黄土丘陵区坡改梯田土壤碳库组分演变特征  

Evolution of Soil Carbon Fraction after Slope CropLand Changed into Terrace in Loess Hilly Region

作　　者：张超[1] 刘国彬[1,2] 薛萐[1] 余娜[2] 

机构地区：[1]西北农林科技大学林学院,陕西杨陵712100 [2]中国科学院水利部水土保持研究所,陕西杨陵712100

出　　处：《水土保持研究》2010年第1期20-23,30,共5页Research of Soil and Water Conservation

基　　金：国家重点基础研究发展规划项目(2007CB407205);中国科学院西部行动计划项目(KZCX2-XB2-05);国家自然科学基金(40801094)

摘　　要：采取时空互代法,以黄土丘陵区不同年限坡耕地改造梯田为研究对象,选取坡耕地为对照,分析了土壤碳库组分的变化过程。结果表明:坡耕地改造梯田后,土壤碳库组分变化显著,并随改造年限呈线性增加,30年后,土壤有机碳(TOC)、重铬酸钾易氧化态碳(EOC1)、高锰酸钾易氧化态碳(EOC2)、水溶性有机碳(DOC)、热水浸提有机碳(HWOC)、K2SO4浸提有机碳(CK2SO4)、碳水化合物(CHO)以及微生物量碳(MBC)较坡耕地增幅分别达146%、213%、196%、97%、246%、240%、234%和134%。相关性分析表明:TOC、EOC1、EOC2、DOC、HWOC、CHO和MBC与土壤主要肥力因子相关性显著,可以作为坡耕地改造梯田中土壤质量的评价指标。研究表明,侵蚀环境下的坡耕地由于受到人为活动的干扰,土壤碳库含量较低,而坡耕地改造成梯田可以提高土壤碳库各组分含量,改善土壤质量。Terraces at different years in loess hilly region was chosen as subject to reveal changes in soil carbon fraction after slope cropland changed into terraces and the slope cropland was used as reference.The results showed that after slope cropland changed into terraces,the content of soil carbon fraction increased linearly and 30 years later,TOC,EOC1,EOC2,DOC,HWOC,CK2SO4,CHO and MBC,respectively,increased by 146%,213%,196%,97%,246%,240%,234% and 134% compared to slope cropland.Moreover,correlation analysis showed that TOC,EOC1,EOC2,DOC,HWOC,CHO and MBC significantly correlated with soil main fertility factors,they can be used as indicators to assess soil quality during slope cropland changed into terraces.It can be concluded that slope cropland changed into terrace can improve content of soil carbon fraction and soil quality which was poor in slope cropland under erosive environment owing to human cultivation activities.

关 键 词：碳库组分 坡耕地 梯田 黄土丘陵区 

分 类 号：S157.31[农业科学—土壤学] S153.61[农业科学—农业基础科学]