摘要
甘肃黑方台地区由于长期大水漫灌引起台塬沉陷、塬边滑坡等自然灾害。为研究沉陷区域的空间分布特征和成因,以2017年9月—2020年11月的Sentinel-1A影像为数据源,利用永久散射体(PS)与短基线集(SBAS)技术提取研究区地表沉陷信息;选取新源村与党川村滑坡高相干点D1、D2,结合灌溉、降雨、温度数据对两种结果进行交叉验证与分析。结果表明:(1)两种技术识别的沉陷区域主要分布于新源村、方台村、朱王村、陈家村以及台塬周边,利用PS与SBAS技术在新源村和党川村解算得到的最大年均沉降速率分别为31.75 mm、28.65 mm和32.6 mm、28.4 mm,两种技术在空间分布和解算结果上一致性较高,SBAS技术提取的沉降点数量多于PS技术;(2)由于2—3月温差较大,随着温度升高引起冻土融化,新源村与党川村滑坡均出现沉陷趋势,6—8月灌溉量和降雨量增多,导致黄土台塬沉陷,滑坡频发,8月后灌溉量与降雨量减少,新源村沉陷速率趋于平缓,而党川村滑坡在10月后产生冻结滞水效应,沉陷有加剧的趋势。两种技术可为黑方台地区健康发展与灾害防治提供科学依据与参考。
The plateau subsidence and tableland edge landslide were caused by long-term flood irrigation in Heifangtai of Yongjing,Gansu Province.In order to study the spatial distribution characteristics and causes of subsidence area,taking the Sentinel-1A images from September 2017to November 2020 as data sources,we used PS and SBAS technologies to extract the surface subsidence information in the study area.Then,combining with irrigation,rainfall and temperature data,we selected the high coherence points D1and D2located in Xinyuan Village and Dangchuan Village,and cross-verified and analyzed the two sets of results.The results show that(1)the subsidence areas identified by the two technologies are distributed equally in Xinyuan Village,Fangtai Village,Zhuwang Village,Chenjia Village and the surrounding area of tableland edge.The maximum annual average subsidence rates calculated by PS and SBAS in Xinyuan Village are 31.75 mm and 28.65 mm,respectively,and in Dangchuan Village are 32.6 mm and 28.4 mm,respectively.The spatial distribution and calculation results of two techniques are consistent.(2)Due to the great temperature difference between Xinyuan Village and Dangchuan Village from February to March,both areas show a tendency of subsidence with the increase of temperature.From June to August,large-scale irrigation and increased rainfall lead to the subsidence of loess tableland edge and frequent landslides.After August,irrigation and rainfall decrease,the subsidence rate of Xinyuan Village tends to be flat,and the subsidence of Dangchuan Village has a tendency to intensify,which is closely related to the occurrence of landslide disaster in January 2021.These two technologies can provide scientific basis and reference for the healthy development and disaster prevention in Heifangtai.
作者
张辉
党星海
李旺平
赵健赟
贾丽奇
张秀霞
郝君明
周兆叶
樊新成
ZHANG Hui;DANG Xinghai;LI Wangping;ZHAO Jianyun;JIA Liqi;ZHANG Xiuxia;HAO Junming;ZHOU Zhaoye;FAN Xincheng(School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Architectural Survey and Design Institute,Lanzhou University of Technology,Lanzhou 730050,China;Department of Geologic Engineering,Qinghai University,Xining 810016,China;School of Design Arts,Lanzhou University of Technology,Lanzhou 730050,China)
出处
《地理空间信息》
2023年第3期52-58,共7页
Geospatial Information
基金
国家自然科学基金资助项目(51968042)。
