Publications

Zhang, L; Xin, ZH; Feng, L; Hu, CM; Zhou, HC; Wang, Y; Song, CC; Zhang, C (2022). Turbidity dynamics of large lakes and reservoirs in northeastern China in response to natural factors and human activities. JOURNAL OF CLEANER PRODUCTION, 368, 133148.

Abstract
The water environment has experienced prominent changes worldwide in recent decades, especially in inland waters. As an important lake region in China, the water turbidity of lakes/reservoirs in the Northeast Plain -Mountainous Region (NPLR) remains less understood, especially the influencing mechanisms of regional cli-matic conditions and human activities. To enhance the knowledge of turbidity dynamics and explanatory var-iables of NPLR water bodies, long-term turbidity estimates of lakes/reservoirs were derived from Moderate Resolution Imaging Spectroradiometer (MODIS)-Aqua observations between 2003 and 2019. The results show that most lakes/reservoirs became less turbid in NPLR during the study period, as indicated by a decreasing turbidity trend of 0.05-2.4 nephelometric turbidity units (NTU)/year. Overall, the decreased turbidity was mainly attributed to the decreased wind speed (from 2003 to 2012, r = 0.85, p < 0.01), but also to the increased normalized difference vegetation index (NDVI) of the forest region (r =-0.80, p < 0.01), with the latter being a result of the forest protection efforts of the Chinese government. The increased snowmelt depth also contributed to a substantial turbidity decline in April. In addition, distinct seasonal patterns of turbidity were observed in the NPLR, with less turbid water in the wet season (i.e., from June to August) and turbid water in the dry season (i.e., October, November, and April in the next year). This result is attributed to the rapid seasonal dynamics of precipitation and runoff. This study provided a comprehensive analysis on the influencing mechanisms of turbidity dynamics in NPLR lakes; in particular, for the first time, revealed the impacts of the national policy -mandated forest development and the snowmelt depth on lake turbidity. These findings will provide vital in-formation for government decision-making in water environment protection in NPLR and other similar areas with densely distributed lakes.

DOI:
10.1016/j.jclepro.2022.133148

ISSN:
1879-1786