Artigo

Resumo: Under ihe joint effects of climate change and human activities, lake ecosystem and its services have changed. It is crucial to study on the dynamics and impact factors of aquatic ecosystem services of lakes for maintaining ecosystem health and achieving sustainable utilization of their functions. Qinghai Lake, located in a climate-sensitive and ecologically vulnerable area, was selected as the study area. Based on the characteristics and current conservation status of aquatic ecosystem of Qinghai Lake, an index system for evaluating gross aquatic ecosystem product was established, including eight assessment indicators, which belonged to two categories including regulation services and cultural services. Gross aquatic ecosystem product of Qinghai Lake from 2010 to 2020 were calculated, and the change trend and major influencing factors were also analyzed. From 2010 to 2020, the gross aquatic ecosystem product of Qinghai Lake ranged from 690.347 billion RMB to 784.855 billion RMB, showing an overall fluctuating upward trend. Regulation service was the major type of aquatic ecosystem services of Qinghai Lake, the value of which accounted for 91%. Over the decade, except for climate regulation and water purification, the value of other ecosystem services increased. The value of water conservation increased the most, by 76.070 billion RMB, while the value of climate regulation decreased the most, by 65.859 billion RMB. Partial least squares regression analysis showed that water temperature and water level were the major effect factors for gross aquatic ecosystem product of Qinghai Lake. Under the effect of climate change, the increase in water temperature raised primary productivity and fish population. Meanwhile, the salinity of Qinghai Lake decreased in recent years, contributing to the growth of aquatic organisms, increasing the value of carbon sequestration and oxygen release, and biodiversity conservation. The increase in water level and surface area increased the value of water conservation, flood regulation and storage. The decline in the value of climate regulation was due to the decrease in evaporation in Qinghai Lake Basin. Under the effect of human rational utilization and conservation, the value of biodiversity conservation, leisure tourism, and scientific research and education were significantly improved. This study quantitatively assessed the contribution of Qinghai Lake aquatic ecosystem to human, and provided a scientific basis of the quantitative evaluation of the restoration of degraded aquatic ecosystem and the effect of ecological conservation measures under the changing environment. We suggested to calculate the gross aquatic ecosystem product of Qinghai Lake regularly and conduct follow-up evaluation of the changes in the aquatic ecosystem of Qinghai Lake, which plays an essential role in maintaining the ecological security of the northeast Qinghai-Tibet Plateau. © 2024 by Journal of Lake Sciences.