摘要
以青土湖干涸湖底为研究对象,选择9种立地类型,利用积沙仪开展风沙流结构的观测,分析不同立地0~30 cm高度风沙流输沙率、粒径组成、粒度参数的变化特征。结果表明:0~30 cm高度范围内,7种立地类型输沙率和输沙通量与高度呈负幂数函数关系;湖底不同立地输沙通量主要集中在近地表0~20 cm,除固定沙丘白刺灌丛,其他类型输沙通量均占0~30 cm高度输沙总量的80%以上,其中湖底滩地、湖底盐爪爪群落、流动白刺灌丛0~30 cm高度范围内风沙流输沙率均较大;输沙率较大的3种立地风沙流颗粒物主要为细砂,次之为粗砂,粉粒含量较低,随着高度增加,3种立地输沙通量中粗砂粒含量均为先轻度增加后递减的趋势,而细砂粒含量则呈先轻度下降后增加的趋势,粉粒含量随高度的增加呈小幅递增趋势;3种立地0~30 cm高度风沙流输沙颗粒的粒径分选属较好-中等,偏度值随着高度增加表现为从近对称趋于正偏,峰度值属于中等峰态分布。
We monitored the structure of wind-sand flow in nine types of sites in the dry bottom of Qingtu Lake by sand accumulation instrument and analyzed the variations of sediment transport rate,grain size composition and grain size parameters of wind-sand flow at the height of 0-30 cm in different sites.The results showed that the sediment transport rates and fluxes of seven site types had negative power function relationship with height of 0-30 cm.The sediment transport fluxes of different sites were mainly concentrated in the near-surface area of 0-20 cm height.Except for fixed-dune Nitraria tangutorum shrub,the sediment transport fluxes of other types accounted for more than 80%of the total sediment transport fluxes at the 0-30 cm height.The sand transport rates of wind-sand flow were high in the height range of 0-30 cm among lake shoal,Kalidium foliatum community in lakebed,and moving-dune Nitraria tangutorum shrub.The grain content of wind-sand flow in the three types of sites with higher sand transport rate was mainly composed of fine sand,followed by coarse sand and silt.With increasing height,the content of coarse sand in the three types of sites increased slightly at first and then decreased,while the content of fine sand decreased slightly at first and then increased,and the content of silt increased slightly.The grain size classification of the three types of sites was under the levels of good-moderate.The skewness value shifted from near symmetry to positive deviation with the increasing height,while the kurtosis value belonged to medium kurtosis distribution.
作者
郭树江
杨自辉
王强强
王多泽
王飞
安富博
张逸君
李易珺
王明国
GUO Shu-jiang;YANG Zi-hui;WANG Qiang-qiang;WANG Duo-ze;WANG fei;AN Fu-bo;ZHANG Yi-jun;LI Yi-jun;WANG Ming-guo(Gansu Desert Control Research Institute,Lanzhou 730070,China;Gansu Minqin National Studies Station for Desert Steppe Ecosystem,Minqin 733300,Gansu,China;State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating,Wuwei 733000,Gansu,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2021年第4期1166-1176,共11页
Chinese Journal of Ecology
基金
国家自然科学基金项目(31760238、31960334、32060371和32060378)
甘肃省自然基金项目(20JR5RA095)资助。
关键词
青土湖
风沙流
输沙率
结构
粒度参数
Qingtu Lake
wind-sand flow
sediment transport rate
structure
grain size parameter
