放牧强度对小针茅草原枯落物分解的影响  

Influence of grazing intensities on litter decomposition of Stipa klemenzii desert steppe

作　　者：姚国征[1] 杨婷婷[2] 高永[1] 丁勇[2] 郭利彪[2] 孙世贤[2] 

机构地区：[1]内蒙古农业大学生态环境学院,呼和浩特010018 [2]中国农业科学院草原研究所,呼和浩特010010

出　　处：《干旱区资源与环境》2017年第7期167-171,共5页Journal of Arid Land Resources and Environment

基　　金：国家重点基础研究发展计划(973计划)项目(2014CB138805);内蒙古自然科学基金(2014BS0331);国家科技支撑计划课题(2012BAD13B07)资助

摘　　要：文中依托内蒙古苏尼特右旗中国农业科学院荒漠草原试验示范基地的放牧控制试验平台,研究了不同放牧强度下小针茅草原枯落物的残留率、分解速率和质量损失率的动态变化,并探讨了分解速率与水热因子的关系。研究结果表明:1)经过一个生长季的分解,放牧不同程度地加速了枯落物的分解。中度放牧小区群落枯落物的分解速率最高,为1.225×10^(-3)g·d^(-1),比对照区高35.28%。2)随着分解时间的延长,不同放牧强度下小针茅群落枯落物的质量累积损失率呈增加的趋势。3)枯落物分解的质量损失量在不同的季节其增加的快慢有差异,在分解的5~7月,枯落物月质量损失量迅速增加,8月份以后枯落物月质量损失量开始降低。不同放牧强度下枯落物质量损失量大小依次为:MG>EG>HG>LG>CK。说明适度放牧有利于枯落物的分解。4)7月份枯落物的分解速率最快,其次为8月份,7、8月份水热条件较好,有利于土壤微生物的生长和繁殖,对枯落物的分解具有促进作用。In Desert Steppe Trial Dases of Sonid Youqi in Inner Mongolia, 5 different treatments which are CK, light grazing, moderate grazing, heavy grazing and extremely heavy grazing were set up. Dynamics of Litter re- maining mass, decomposition rate, the quality loss rate were measured from May to September in 2014. The effects of temperature and precipitation on litter decomposition were analyzed. The results showed that： （ 1 ） after the decomposition in a growing season, grazing accelerats the litter decomposition in different degrees. The litter decomposition rate in MG is the highest, which is 1. 225 ×10^-3g·d^-1, 35.28% higher than that in CK. （2） With the increasing of decomposition time, the litter quality loss rate under different grazing intensities in- creased. （3） In different seasons, the increasing speed of the litter quality loss mass is different, from May to July, the monthly litter quality loss mass increases, after August, it decreases. The litter quality loss mass under different grazing intensity is as follows ： MG 〉 EG 〉 HG 〉 LG 〉 CK, it suggests that moderate grazing is advanta- geous to the litter decomposition. （4） Litter decomposition rate is the highest in July, followed by August. Hy- drothermal condition is good in July and August, which promots the growth and reproduction of soil microorgan- isms, and has promoting effect on litter decomposition.

关 键 词：小针茅草原 枯落物 分解速率 不同放牧强度 

分 类 号：S812[农业科学—草业科学]