Optimal lake‐marsh pattern determination in lake‐marsh systems based on the eco‐hydrological processes management

• Published in: Hydrological processes 2020-12, Vol.34 (26), p.5260-5277
• Main Authors: Bi, Wuxia, Weng, Baisha, Yan, Denghua, Li, Meng, Yu, Zhilei, Wang, Lin, Wang, Hao
• Format: Article
• Language: English
• Subjects: Alternations; area proportion; Climate and land use; Climate change; ecological services values; Ecology; Evapotranspiration; Groundwater; Hydrologic processes; Hydrology; Lakes; lake‐marsh systems; Land use; Marshes; Mathematical analysis; optimal pattern; protection objects; Socioeconomic factors; Socioeconomics; Surface area; Surface water; Surface-groundwater relations; Vegetation; Volume transport; Water demand; Water depth; water level; Water levels; water shortage amount; Water shortages; Water supply; Water use; Wetland management; Wetlands; Wolonghu Wetlands
• ISSN: 0885-6087; 1099-1085
• DOI: 10.1002/hyp.13941

The major hydrological factors in lake‐marsh systems are water level (depth), water surface area, and water volume. The key index for determining the lake‐marsh pattern is water level, which leads to the variation of lake‐marsh patterns under natural hydrological alternations. In addition, the vegetation structure also affects the lake‐marsh pattern. With socioeconomic development and climate change, the ‘land use’ and ‘water use’ competitions appear more seriously between a lake‐marsh system and its surrounding socioeconomic system, also inside the lake‐marsh system. The possible optimal lake‐marsh pattern could solve the contradictions mentioned above. As few studies focus on this issue, this study proposed an optimal lake‐marsh pattern determination method with eco‐hydrological management on relieving the land use and water use competitions. The optimal lake‐marsh pattern determination method considers the protection objects (water depth demands), water supply (precipitation, surface water, and groundwater), and water demand (especially evapotranspiration) in the system at annual and monthly scales. Calculation and analysis were performed for the optimal pattern of the Wolonghu Wetlands as an example. The results mainly showed that the lake‐marsh pattern of the Wolonghu Wetlands cannot be achieved on meeting both the maximum ecological services values and minimum water shortage amount under present natural condition. With artificial regulation measures, the possible optimal annual lake‐marsh patterns can be obtained based on both ecological and hydrological objectives, with the area ratio of lake and marsh in the range of 0.650:0.350 and 0.726:0.274, the corresponding water level of lake body was of 86.85 to 87.0 m. This study could provide references for the Wolonghu Wetlands management, also for similar lake‐marsh systems and other ecological systems. Optimal lake‐marsh pattern determination in the Wolonghu Wetlands based on the eco‐hydrological processes management.