Study on the effects of agricultural reclamation on the optical water quality parameters of lakes

As an important water source for human activities and economic development, the protection of lake water quality is crucial, and the mechanisms by which different types of agricultural activities affect lake water quality is urgently needed further in-depth study. With the continuous expansion of agricultural reclamation activities, processes such as farmland fertilization, pesticide use, and changes in land cover have significantly altered the patterns of material input and energy transfer in lakes, necessitating an in-depth study of their quantitative relationship with lake water quality parameters. Although existing studies have focused on the impact of agricultural activities on lake water quality, the mechanisms by which different types of cultivation, spatial patterns, and climatic conditions affect lake optical water quality parameters are still not well understood. Lake optical water quality parameters (such as chlorophyll-a (Chl-a), total suspended particulate matter (TSM), and colored dissolved organic matter (CDOM)) not only reflect the nutrient status and biological productivity of the water body, but also serve as important inputs and validation indicators for remote sensing-based water quality models. Based on recent domestic and international research results, this paper uses a combination method of bibliometrics and case analysis to review the current research status of inversion models for lake optical water quality parameters, including inversion techniques and progress of key optical water quality parameters such as chlorophyll a, inorganic suspended solids, and colored soluble organic matter. It also systematically reviews the latest research results on the impact of agricultural reclamation on optical water quality parameters of lakes, revealing the mechanisms by which agricultural activities affect lake water quality through pathways such as nutrient input, particulate matter input, and organic matter accumulation. Furthermore, through typical lake case studies (e.g., lakes in different climate zones, land use structures, and reclamation history backgrounds), the specific impacts of heterogeneity in agricultural reclamation structures on lake optical water quality parameters is explored, providing a scientific reference for lake ecological protection and sustainable agricultural development.