干热河谷冲沟侵蚀劣地不同坡位草被生长和土壤水分关系研究  

The correlation between soil moisture and grass growth in different slope positions of gully badlands in Dry-hot Valley

作　　者：张宝军[1,2,3] 熊东红[1,2] 郭敏[1,2,3] 董一帆[1,2] 苏正安[1,2] 杨丹[1,2,3] 史亮涛[4] 

机构地区：[1]中国科学院山地灾害与地表过程重点实验室,四川成都610041 [2]中国科学院水利部成都山地灾害与环境研究所,四川成都610041 [3]中国科学院大学,北京100049 [4]云南省农业科学院热区生态农业研究所,云南元谋651300

出　　处：《草业科学》2015年第5期686-693,共8页Pratacultural Science

基　　金：国家重点基础研究发展计划项目(2015CB452704);中国科学院"西部之光"人才培养计划重点项目(Y4R2060060);四川省应用基础研究计划项目(2014JY0067);中国科学院水利部成都山地灾害与环境研究所"青年百人团队"项目(SDSQB-2011-01)

摘　　要：金沙江干热河谷区冲沟侵蚀极为发育,形成大量侵蚀劣地,对该区域侵蚀劣地不同坡位草被生长特征和土壤水分状况进行了调查分析。结果表明,1)侵蚀劣地不同坡位草被生长差异较大,草被盖度和地上生物量大小均表现为:坡上部<坡中部<坡下部,且坡下部与坡上部和坡中部之间草被生长状况存在极显著差异(P<0.01);2)同等降雨状况下,不同坡位土壤水分含量随时间延长均呈现指数递减趋势,但其衰减速率不同,导致土壤水分含量存在差异,衰减速率表现为:坡上部>坡中部>坡下部,土壤水分含量表现为相反顺序;3)监测时段内土壤水分(土壤平均含水量和末次土壤含水量)与草被覆盖度和生物量之间均呈现极显著正相关关系(P<0.01),说明侵蚀劣地不同坡位下土壤水分差异是决定草被生长差异的关键因素。Badlands are extremely developed due to gully erosion in Yuanmou dry-hot valley of Jinsha River.Grass growth characteristics and soil moisture conditions in different slope positions of gully badlands were surveyed and analyzed.The results showed that there were significant differences(P<0.05)for grass performance in different slope positions of gully badlands,especially,there were highly significant differences(P<0.01)between the upper position and the middle or lower positions in the same slope.Both the grass coverage and aboveground biomass increased in the order of Upper < Middle < Lower.Under the same precipitation conditions,soil moisture in different slope positions declined in exponential trend with different rates over time which resulted in different soil water contents.The declined rates of soil moisture decreased in the order of Upper< Middle< Lower which brought different soil water contents in the reverse order in the same monitoring period.There were significant correlations between soil water content including average(P<0.05)and final(P<0.01)and grass coverage and aboveground biomass during the monitoring periods which indicated that the different soil water content under different slope positions were key factors to determine the grass growth in gully badlands.

关 键 词：坡位 草被生长 土壤水分 侵蚀劣地 冲沟 

分 类 号：S812.2[农业科学—草业科学]