POSTER SESSION 3
15:30–17:30, Wednesday, September 16
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
ABSTRACT 1153 | POSTER 255
CONTRASTING DRIVERS OF WATER CLARITY: A MULTI-DECADAL SATELLITE ANALYSIS OF TWO TYPES OF LAKES
Lakes are critical ecosystems that support water resources, biodiversity conservation, and ecosystem services. However, water clarity (Secchi disk depth, Zsd), is increasingly affected by climatic and anthropogenic disturbances. In this study, Landsat data were used to investigate the spatiotemporal dynamics of Zsd in four Chinese lakes since 1984: two river-flow lakes, Dongting Lake (DTL) and Poyang Lake (PYL), and two non-river-flow lakes, Baiyangdian (BYD) and Hengshui Lake (HSL). Climatic factors, land use, landscape metrics, and major human interventions were integrated to identify dominant drivers and response mechanisms of Zsd variations. The results showed that river-flow lakes exhibited stronger temporal fluctuations and spatial heterogeneity in Zsd than non-river-flow lakes, mainly due to stronger hydrological connectivity, higher precipitation variability, and more frequent water exchange. Distinct interannual trajectories were observed among the four lakes, with Zsd increasing to peak values before declining during different periods. Distributed lag analysis revealed that climatic and landscape drivers exerted delayed effects on Zsd, and the magnitude and one-year lag response differed among lake types. In DTL and PYL, the operation of the Three Gorges Dam may have altered sediment transport and hydrological regimes, influencing Zsd through delayed hydrological responses. In BYD, ecological restoration following the establishment of Xiong’an New Area may have mitigated agricultural impacts and improved clarity. In HSL, water replenishment modified water volume and nutrient inputs, producing complex lagged responses. This study supports long-term monitoring and adaptive management of lake water clarity under coupled climatic and anthropogenic influences.
Yelong Zhao, Northeast Institute of Geography and Agroecology Chinese Academy of Sciences, [email protected]
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
