Chinese Policies and Practices regarding Payments for Ecological Services in Watersheds

Watersheds provide a variety of ecological services including soil and water conservation, carbon sequestration and biodiversity protection. However, activities in a fast-growing economy significantly impact the supply and demand of these watershed services. To mitigate these impacts, the concept of payment for environmental and ecosystem services from water-sheds has emerged in global academic and policy circles. The governments and academic communities in China have increas-ingly described payments for ecological services from watersheds with the concept of watershed eco-compensation as it is urgent to protect watershed ecosystems. Watershed eco-compensation has proved to be one of the most economically effective means of solving environmental problems of watersheds to be adopted by the Chinese government. This paper presents an objective analysis of the Chinese market for watershed ecosystem services, including supply and demand for the services. It also summarizes Chinese policies on watershed eco-compensation, including relevant laws and regulations and fiscal policies. In addition, it presents a re-view of Chinese practices in watershed eco-compensation, in-cluding the analysis of an ecological construction project in West-ern China, inter-provincial watershed eco-compensation practices and plans, and payment for ecological services at the provincial and small watershed levels. Finally, it summarizes the key com-ponents of the process of payment in Chinese watershed eco-compensation. This discussion forms the basis of concluding suggestions for ecosystem services compensation and ecological protection in the large scale river basin.

Effects of different water levels on phytoplankton in the Harbin section of the Songhua River

The functional diversity index of a phytoplankton body has gradually become a new mean of measuring and research.To explore the response of phytoplankton taxonomy and the functional diversity index to interannual environmental changes,a survey on the structure of the phytoplankton community and water physicochemical characteristics of the water was carried out at 28 sampling points in the Harbin section of the Songhua River for three consecutive years in every May from 2021 to 2023.The taxonomy diversity index and the functional diversity index were calculated.Firstly,The relationship between the structure of the characteristics of the community and environmental factors was explored;secondly,we reveal the responses of taxonomic and functional diversity indices to different habitats between years;finally,we explore the main environmental factors that control the taxonomic and functional diversity indices of phytoplankton.Results show that,initially,environmental factors in water changes caused by different water levels between years affected the composition of phytoplankton communities.Subsequently,by comparing the taxonomic diversity index and the functional diversity index on a time scale,we found that the taxonomic diversity index was more responsive to environmental changes.Ultimately,the main environmental factors on the phytoplankton taxonomic diversity index were dissolved oxygen,Taxonomic diversity index,and specific conductivity,and the main environmental factors that affected the functional diversity index were dissolved oxygen,turbidity,and water temperature.This study reveals the important role of the taxonomic diversity index in river water quality evaluation,obtained new information on the relative precision of the taxonomic diversity index and the functional diversity index in the evaluation of ecological health of the water,and provided a reliable tool for monitoring river water quality based on aquatic organisms.

Urbanization reduces resource use efficiency of phytoplankton community by altering the environment and decreasing biodiversity

Urbanization often exerts multiple effects on aquatic and terrestrial organisms,including changes in biodiversity,species composition and ecosystem functions.However,the impacts of urbanization on river phytoplankton in subtropical urbanizing watersheds remain largely unknown.Here,we explored the effects of urbanization on phytoplankton community structure(i.e.,biomass,community composition and diversity)and function(i.e.,resource use efficiency)in a subtropical river at watershed scale in southeast China over 6 years.A total of 318 phytoplankton species belonging into 120 genera and 7 phyla were identified from 108 samples.Bacillariophyta biomass showed an increasing trend with increasing urbanization level.The phytoplankton community shifted from Chlorophyta dominance in rural upstream waters to Bacillariophyta dominance in urbanized downstream waters.Furthermore,phytoplankton diversity and resource use efficiency(RUE=phytoplankton biomass/total phosphorus)were significantly decreased with increasing urbanization level from upstream to downstream.Phytoplankton RUE exhibited a significant positive correlation with species richness,but a negative correlation with phytoplankton evenness.The variation in environmental factors(turbidity,total nitrogen,NH_(4)^(+)-N,total phosphorus,PO_(4)^(3-)-P and percentage urbanized area)was significantly correlated with phytoplankton diversity and RUE.Overall,our results revealed the influence of urbanization on phytoplankton community structure and ecosystem function was due to its altering the environmental conditions.Therefore,human-driven urbanization may play crucial roles in shaping the structure and function of phytoplankton communities in subtropical rivers,and the mechanism of this process can provide important information for freshwater sustainable uses,watershed management and conservation.