摘要
地面重力变化是研究重力场时空变化的重要方面,而土壤水变化的对重力的影响范围和程度分析还存在不足。利用美国国家海洋和大气管理局气象预报中心提供的全球气候预测模型提取了‘2010年1月至2015年6月长江中上游流域的月平均土壤水含量数据,将土壤水等效水高格网进行规格化球谐展开,通过负荷理论,计算出长江中上游流域土壤水变化对该区域地面重力的影响。通过对结果的对比分析,研究发现:①土壤水含量增加,引起的地面重力增大,在三峡大坝上游导致的地面重力变化较小,三峡大坝下游的江汉平原附近引起的地面重力减小幅度较大;②长江中上游流域土壤水含量年变化幅度约为0.5m,其变化引起的地面重力变化年变化幅度约为8.12“Gal。将进一步加深土壤水含量变化对地面重力的影响的认识,丰富了长江中上游流域重力场变化影响因素的研究,为长江中上游流域水动力环境研究提供了一定的参考。
The study of ground gravity change is an important aspect of temporal and spatial variation of the gravitational field,but the extent analysis of soil moisture changes on the gravity and its influence are still insufficient.In this paper, first,we extract the average monthly water soil water con- tent data from the gloha[climate prediction model provided by NOAA and CPC from January 2010to June 2015of the upper and middle reaches of the Yangtze River.Second,we expand the normalized spherical harmonic of the soil water e- quivaIent high water grids by Load Theory to calculate the change of the soil water in the upper and middle reaches of the Yangtze River o5the ground gravity effect on the region. By comparative analysis of the results,we find that 1)the rise of soil water increases the gravity on the ground.The change of ground gravity caused by the upper reaches of the Three Gorges Dam is small,the decrease of ground gravity caused by the Jianghan Plain near the Three Gorges Dam is large;2)The annual change ofsoil water content is about 0. 5m,and the annual change of ground gravity caused by the change is about 8.12μGal.This paper deepens the under- standing of the impact of changes in soil water content on ground gravity,enriches the study of changes in the gravita- tional field influencing factors in the upper and middle rea- ches of the Yangtze River,and provides reference for the study of hydrodynamic environment in the Upper and middle reaches of the Yangtze River.
作者
杨阳
高永泉
王伟
杨国林
李兴桥
尹财
YANG Yang;GAO Yongquan;WANG Wei;YANG Guolin;LI Xingqiao;YIN Cai(College of Surveying and Geomatics,Lanzhou .liaotong University,Lanzhou 730070,China;Chinese Academy of Surveying and Mapping,Beijing 100830,China;Gansu Province Geographical Situation Monitoring Engineering Laboratory,Lanzhou 730070,China;College of Urban and Rural Construction,Hebei Agricultural University,Baoding 071001,China;School of Surveying and Mapping,Shandong University of Science ancl Technology,Qingdao 266590,China)
出处
《测绘地理信息》
2018年第6期66-69,共4页
Journal of Geomatics
基金
国家自然科学基金资助项目(41304009,41374081)
甘肃省自然科学基金资助项目(148RJZA039)
关键词
长江中上游流域
土壤水
地面重力
负荷理论
upper and middle reaches of the Yangtze River
soil
ground gravity
Load theory
