科尔沁沙地沙丘生境单元凋落物运移特征  

Characteristics of Litter Migration in Habitat Units of Dunes in the Horqin Sandy Land

作　　者：王新源[1,2] 赵学勇[1] 李玉霖[1] 陈翔舜 王小军 云建英[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所,甘肃兰州730000 [2]甘肃省生态环境监测监督管理局,甘肃兰州730020

出　　处：《中国沙漠》2016年第1期167-173,共7页Journal of Desert Research

基　　金：中国科学院战略性先导科技专项(XDA05050406-4);国家自然科学基金项目(31270501;41171414)

摘　　要：通过测定科尔沁沙地沙丘生境单元凋落物的运移量,分析了沙丘类型和生境变化对凋落物运移的影响,并探讨了是否可以通过凋落物运移量的变化来判断营养物质的迁移。结果表明：科尔沁沙地沙丘凋落物的运移过程主要发生在非生长季,呈明显的单峰型季节波动。凋落物运移量在不同沙丘的丘间地、迎风坡、丘顶和背风坡均表现出明显的空间差异性,丘顶的凋落物运移量最大,迎风坡次之,丘间地和背风坡相对较小。凋落物运移量有随距地表高度增加而下降的趋势,距地表高度为0~25cm时,凋落物运移量最大,显著高于25~50、50~75、75~100cm3个高度区间。凋落物运移量与风速在流动沙丘、半固定沙丘和固定沙丘均呈显著的二次曲线正相关,显示风速是影响凋落物运移量动态变化的重要因素。Through the observation of litter migration flux among windward slope,top,leeward slope and inter-dune in different sand dunes,we analyzed the responses of litter migration to different habitats and sand dunes,and tried to explore the changes of litter migration for identifying the dynamics and allocation patterns of nutrients.The results showed that the process of litter migration was mainly observed during the non-growing seasons,coinciding with high litter production and strong wind.Litter migration flux varied markedly among the 4 habitat units in different sand dunes,being much higher at dune top and windward slope while much lower in the leeward slop and inter-dune.Additionally,there is a decreasing trend of the litter migration flux along the increase of height from the ground,and litter migration flux were significantly greater at height of 0-25 cm than at height of 25-50 cm,50-75 cm and 75-100 cm.Whether in mobile dune,semi-fixed dune and fixed dune,there was a significant positive quadratic correlation between wind velocity and litter migration flux.In summary,the dynamic changes of litter migration flux were generally directly related to wind velocity.

关 键 词：科尔沁沙地 生境单元 风速 凋落物运移量 

分 类 号：Q948.11[生物学—植物学]