摘要
选取红碱淖湖泊1957-2015年近60 a合计15期DRG、DLG、DOM、遥感影像、纸质地图等基础数据和遥感影像数据,辅以野外调绘资料及相关属性数据,综合利用RS、GIS、GPS等技术,采用空间数据处理、信息提取解译、海量数据建库、集成管理分析等方法,分析了研究区近60 a水域面积时空变化特征及趋势,同时结合同时期气候变化和人类活动因素,探讨了引起湖泊水域面积时空变化的主要原因。结果表明:近60 a研究区水域面积发生了显著变化:1)1957-1976年,水域面积持续增长并达到近60 a极大值,由1957年的37.6 km^2增至1976年的55.53 km^2,增幅高达47.69%,以湖泊北侧、南右侧区域增幅速度相对较快,其他区域次之;2)1977-1999年,水域面积整体状况稳定,维持在50 km^2左右;3)2000-2015年,水域面积呈逐年萎缩趋势,由1999年的50.27 km^2减少至2015年的31.05 km^2,减幅达38.23%,除七卜素河附近水域在2005年出现逆转面积略有增加外,其他区域均呈现规律性萎缩趋势;总体来看,近60 a间红碱淖湖泊水域面积演变过程依据水域面积年间变化率可以划分为扩张期(1957-1976)、稳定期(1977-1999)、萎缩期(2000-2015)3个阶段,总体呈现萎缩趋势;气候暖干化趋势是影响扩张期和稳定期湖泊水域面积变化的主要因素,气候暖干化叠加人类活动(上游水利工程修建、煤矿开采、环湖路面建设、灌溉耗水等)是造成萎缩期湖泊水域面积变化的关键因素。
The changes of lake water resources record the impacts of climate changes and human activities on the regional hydrological processes in the changing environment.Especially for inland areas with less precipitation,timely and accurate information on changes in lake water resources are recorded.Environmental evolution has an important reference value.With China's largest desert freshwater lake-Hongjiannao Lake as an example,based on the 3 S(RS,GIS,and GPS,which are remote sensing,global position system,geographic information system) technology,lake water surface area change was analyzed,which provided important scientific guidance for the restoration,protection and utilization of ecological and economic functions of Hongjiannao Lake.However,due to the different sources of data,the uneven technology,the discontinuous time series and the generally short time series,as well as the different monitoring phases,the result analysis on the change of water area of Hongjiannao Lake is quite different and systematic study and overall analysis of long time series of the entire river basin are lacking.Fifteen periods of both basic and RS data collected for Hongjiannao Lake,such as DRG,DLG,DOM,remote sensing images,and paper maps,were selected for analysis over a recent 60-year period(from 1957 to 2015),together with field annotation data and relevant attributes.All the data and images above have passed the geometric correction of digital elevation model data from Shaanxi Surveying and Mapping Archives and Geological Information Bureau of State Bureau of Surveying and Mapping,which have good quality.Different data can meet the high-precision registration requirements of water body information extraction in the study area.Among them,NDWI(normalized difference water index) with better extraction effect was used to extract water body information,which could restrain the vegetation soil while enhance the water body information.To analyze characteristics in spatio-temporal variations and identify trends of the change in lake water area over the period,we comprehensively utilized RS and GIS techniques and adopted spatial data processes,extracted and interpreted information,constructed a massive database,and conducted integrated management and analysis.We also explored major causes that triggered spatio-temporal variations of lake water area by combining climate change and anthropogenic factors from the same period.Results indicated that in a recent 60-year period,the area covered by water significantly changed in the study area.During 1957-1976,the water area continuously increased from 37.6 to 55.53 km2,and reached the maximum value over the entire record of study with increased amplitude of 47.69%.The growth rates in northern and southeastern areas of the lake were relatively fast,followed by other regions.During 1977-1999,the overall water area was stable,approximately 50 km2.During 2000-2015,water area showed a decreasing trend year by year,from 50.27 to 31.05 km2 with decreased amplitude of 38.23%,and all regions showed this shrinking trend except waters near Qibusu River in 2005,in which the reverse occurred and the water area slightly increased.In general,over the last 60 years,the revolution process of the water area of Hongjiannao Lake could be divided into 3 phases corresponding to the annual variability of water area:expanding period(1957-1976),stabilizing period(1977-1999),and shrinking period(2000-2015),showing an overall shrinking trend.The area of lakes and waters has experienced a dynamic trend of expansion-stabilization-atrophy in the recent 60 years,and has shown a significant atrophy situation since 1999 and a strong signal of ecological and hydrological deterioration,deserving attention.Trends in both warming and drying climate may be the major factors,which affect lake water area variation in both expanding and stabilizing periods,and the superimposition of these trends with anthropogenic effects(i.e.a water conservation project construction in the upper streams,coal mining,pavement construction around the lake,and water consumption for irrigation) may be the essential factor leading to water area variations during the shrinking period.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2018年第2期265-271,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
地震科技星火计划青年项目(XH16056Y)
国家自然科学基金项目(51409226
51769036)
关键词
遥感
监测
气候变化
红碱淖湖泊
时空变化
人类活动
remote sensing
monitoring
climate changes
Hongjiannao Lake
spatio-temporal changes
human activity