Jeihouni Mehrdad, Toomanian Ara, Alavipanah Seyed Kazem, Hamzeh Saeid
Department of Remote Sensing and GIS, Faculty of Geography, University of Tehran, Azin Alley. 50, Vesal Str., Tehran, Iran.
Environ Monit Assess. 2017 Oct 18;189(11):572. doi: 10.1007/s10661-017-6308-5.
Preserving aquatic ecosystems and water resources management is crucial in arid and semi-arid regions for anthropogenic reasons and climate change. In recent decades, the water level of the largest lake in Iran, Urmia Lake, has decreased sharply, which has become a major environmental concern in Iran and the region. The efforts to revive the lake concerns the amount of water required for restoration. This study monitored and assessed Urmia Lake status over a period of 30 years (1984 to 2014) using remotely sensed data. A novel method is proposed that generates a lakebed digital elevation model (LBDEM) for Urmia Lake based on time series images from Landsat satellites, water level field measurements, remote sensing techniques, GIS, and 3D modeling. The volume of water required to restore the Lake water level to that of previous years and the ecological water level was calculated based on LBDEM. The results indicate a marked change in the area and volume of the lake from its maximum water level in 1998 to its minimum level in 2014. During this period, 86% of the lake became a salt desert and the volume of the lake water in 2013 was just 0.83% of the 1998 volume. The volume of water required to restore Urmia Lake from benchmark status (in 2014) to ecological water level (1274.10 m) is 12.546 Bm, excluding evaporation. The results and the proposed method can be used by national and international environmental organizations to monitor and assess the status of Urmia Lake and support them in decision-making.
出于人为因素和气候变化的考虑，在干旱和半干旱地区保护水生生态系统和进行水资源管理至关重要。近几十年来，伊朗最大的湖泊乌尔米耶湖的水位急剧下降，这已成为伊朗及该地区的一个主要环境问题。恢复该湖的努力涉及到恢复所需的水量。本研究利用遥感数据对乌尔米耶湖30年（1984年至2014年）的状况进行了监测和评估。提出了一种新方法，该方法基于陆地卫星的时间序列图像、水位实地测量、遥感技术、地理信息系统和三维建模，生成了乌尔米耶湖的湖床数字高程模型（LBDEM）。根据LBDEM计算了将湖泊水位恢复到往年水平和生态水位所需的水量。结果表明，从1998年的最高水位到2014年的最低水位，湖泊的面积和水量发生了显著变化。在此期间，86%的湖泊变成了盐漠，2013年的湖水水量仅为1998年水量的0.83%。将乌尔米耶湖从基准状态（2014年）恢复到生态水位（1274.10米）所需的水量（不包括蒸发量）为125.46亿立方米。研究结果和所提出的方法可供国家和国际环境组织用于监测和评估乌尔米耶湖的状况，并为其决策提供支持。
