Impact of climate change and human activities on economic values produced by ecosystem service functions of rivers in water shortage area of Northwest China

The dynamic evolution of collaborative networks in sustainable development: Untying impact of environmental policy in China using network-based text analysis approach

As one of the key subjects of multi-center governance of environmental concerns, public perception is crucial in forming and implementing environmental policy. Based on data science research theory and the original theory of public perception, this study proposes a research framework to analyze environmental policy through network text analysis. The primary contents are bidirectional encoder representation from transformers-convolution neural network (BERT-CNN) sentiment tendency analysis, word frequency characteristic analysis, and semantic network analysis. The realism of the suggested framework is demonstrated by using the waste classification policy as an example. The findings indicate a substantial relationship between perceived subject participation and policy pilot areas and that perceived subject participation is repeating. On this premise, specific recommendations are made to encourage policy implementation.

Optimal Water Resources Allocation in the Yinma River Basin in Jilin Province, China, Using Fuzzy Programming

Being one of the most important sources of water in the Jilin Province in China, the Yinma River Basin (YRB) is facing problems of water scarcity in low economic areas and low utilization in richer areas mainly caused by the irrational allocation of water, excessive pursuit of economic benefits, and neglect of environmental problems. Restricting watershed development involves potential decision-making risks. Some scholars have used the interval two-stage stochastic planning method to adjust water resource allocation in the Drinking Horse River Basin, but the method uses historical statistics for projection and does not take into account the ambiguity and uncertainty in real planning situations. Therefore, this study addresses the problems prevalent in the allocation of water resources in the YRB through optimization using stochastic programming methods, interval and two-stage, and introduces the fuzzy mathematical programming method, with the aim of coordinating the water balance of various water-consuming sectors in the YRB, so as to reconfigure the water allocation. The goal is to solve the existing problems of irrational water allocation, reduce system risks posed by excessive economic development, mitigate water shortages in the water-consuming sectors, and alleviate potential decision-making risks and vague uncertainties associated with the allocation of water resources. Additionally, optimization of the pollution-holding capacity improvement project was carried out. The interval fuzzy two-stage model simulation developed in this study shows that the distribution of water across the different administrative regions can be reduced by up to 30% compared with the original model, effectively reducing the problem of water wastage. Post-optimization, the impact of water shortage in the water resources allocation scheme is alleviated to a significant degree, and there is no water shortage in some areas. At the same time, the eco-environmental sector has gradually taken the leading role in the distribution of water reuse among the different water-consuming sectors. The pollution-holding capacity has been enhanced, and the discharge and river entry chemical oxygen demand (COD) and ammonia nitrogen, two typical pollutants, have been reduced. The membership interval in the interval fuzzy two-stage model reflects the relationship between the possible level of the target value and the risk level. This study provides a guideline for decision makers for balancing the relationship between benefits and risks and proposes a planning scheme that is more conducive to the development of the river basin.

Spatial–Temporal Variations of Water Ecosystem Services Value and Its Influencing Factors: A Case in Typical Regions of the Central Loess Plateau

Water resources provide indispensable ecosystem services, which are related to human well-being and sustainable social development. Accurately measuring the water ecosystem services value (WESV), and then grasping its changing characteristics, is particularly important for solving water problems. In this study, the typical area of the central Loess Plateau location is taken as the research area. Based on remote sensing images and statistical data, the direct market method combined with the equivalent factor method was used to calculate the WESV including groundwater and surface water, which is of greatest originality. The temporal and spatial variation characteristics in 2010, 2015 and 2020 were analyzed. Then, four WESV driving factors including per capita GDP, population density, proportion of water areas, and water consumption were selected, and the geographically weighted regression (GWR) model was used to analyze the spatial distribution pattern and temporal variation of WESV’s response to the influencing factors. The results showed that WESV experienced a process of first decreasing and then increasing, which was mainly caused by Yulin. For the composition of WESV, the proportion of provisioning services value has increased, which caused the proportion of regulating services value to decrease. The correlations between four factors and WESV were different. The distribution pattern of the influences was spatially heterogeneous, which showed regular variations over time. These results indicate the necessity of WESV’s independent research and provide a realistic basis for ecological compensation in the Yellow River Basin.

The Influence of Organic Matter Origin on the Chlorine Bulk Decay Coefficient in Reclaimed Water

Using reclaimed water has been increasing to manage water shortages arising due to climate change. Research has been conducted on reclaimed water production, but few studies have investigated the pipe network and supply of reclaimed water. Reclaimed water contains greater amounts of organic matter, nutrients, and ionic substances compared to tap water. Therefore, it is highly likely to cause problems, such as water pollution due to microbial propagation in pipes, and leakage due to pipe corrosion, which interfere with water supply system operations. This study investigated the residual chlorine decay characteristics of chlorine disinfectants applied to a control biofilm in reclaimed water pipe networks. The bulk decay coefficient was compared between reclaimed water and a humic acid solution, and the origin of organic matter was analyzed using fluorescence excitation-emission matrices. The experimental results show that residual chlorine was consumed because protein and amino acid-based organic matter reacted more rapidly with chlorine than natural organic matter, such as humic acid. Moreover, chlorine bulk decay occurred rapidly in reclaimed water when total organic carbon was 3 mg/L or higher. These results confirm that removing organic matter during reclaimed water treatment may affect the management of the pipe network system.

Impacts of land use change on ecosystem service value in Lijiang River Basin, China

It is of great significance for the coordinated development of the environment and the economy to study the impact of the human driving factors of land use change (LUC) on ecosystem service value (ESV). In this study, we combined the biomass and remote sensing data of the Lijiang River Basin (LRB), which is a typical karst basin with a fragile ecological environment, to establish an ESV model to calculate the ESV. We also introduced the Lorenz curve and Gini coefficient to further analyze the impacts of the human driving factors of LUC on ESV. The results show that (1) the ESV in the LRB from 1995 to 2015 decreased from 8640.03 million yuan to 8595.38 million yuan, with a total decrease of 44.65 million yuan, indicating that the overall ESV in the region has a decreasing trend; (2) the obvious changes in land use caused a significant loss in ESV and changes in the structure of ecosystem services; and (3) the human driving factors of the total population, GDP, and urbanization rate are inversely related to the ESV in the LRB.

How diatom-, invertebrate- and fish-based diagnostic tools can support the ecological assessment of rivers in a multi-pressure context: Temporal trends over the past two decades in France

The degradation of aquatic ecosystems, induced by worldwide intensification in the use of both land and aquatic resources, has highlighted the critical need for innovative methods allowing an objective quantification and ranking of anthropogenic pressure effects on aquatic organisms. Such diagnostic tools have a great potential for defining robust management responses to anthropogenic pressures. Our objective was to explore how the outputs of three diagnostic tools (based on benthic diatoms, macroinvertebrates and fishes) could be combined to (i) disentangle the temporal effects of multiple pressures over two decades and (ii) provide policy-relevant information for stream managers and decision makers. The diagnostic tools estimated, using taxonomy- and trait-based metrics, the impairment probabilities of biotic assemblages over time by different pressure categories, describing the alteration of water quality, hydromorphology and land use related to anthropogenic activities, in French streams (number of sites = 312). The main result shows that a large proportion of the time series exhibited no significant temporal patterns over the two decades (61.5% to 87.8%, depending on the used tests). Among time series exhibiting significant change, positive trends in impairment probabilities (i.e., degradation) were less frequent than negative ones, indicating a modest improvement in water quality at national scale over the study period. However, trends can be substantially different according to hydroecoregion and pressure category. The three biological compartments displayed convergent temporal responses according to the pressure category and regional context (e.g., lowland plains vs. mountains, pristine vs. agricultural regions). Altogether, this study proposes a unifying approach to integrate a vast amount of information in a single ecological diagnosis using an unparalleled database on natural and anthropized environments. Strengthening the synthesis of biological information provided by various biological compartments should be a priority before implementing evidence-based sustainable conservation and restoration actions.