Examining the U-shaped relationship between non-agricultural sources water pollution and the urban-rural income gap.

Determining how the economy and society interact with the environment of water quality is essential to determining the financial impact of green development. Based on China's provincial panel data from 2010 to 2021, this research considers non-agricultural sources of water pollution (NASWP) as a negative factor of production, investigates its influence on the urban-rural divide, and explains the mechanism of action. The empirical results show that there is a significant correlation between NASWP and the urban-rural gap, with a "U-shaped" relationship between the two. Water pollution first reduces and then increases the urban-rural income gap, and the results are robust after considering endogeneity. Mechanistic research demonstrates that NASWP cause a loss in food output, which in combination with changes in food prices and food subsidy programs impacts the incomes of rural dwellers, thereby having an influence on the urban-rural income gap. Using the threshold effect model, it is discovered that under the combined influence of agricultural mechanization and food subsidy policy, the relationship between NASWP and urban-rural income divide exhibits an U-shape in areas with high agricultural mechanization and an "inverted U" shape in areas with low agricultural mechanization.

Research on the cooperative mechanism of government and enterprise for basin ecological compensation based on differential game.

Ecological compensation is an important means of basin pollution control, the existing researches mainly focus on the government level ignoring the important role of enterprises. Therefore, this paper introduces enterprises into the process of ecological compensation. Firstly, suppose the ecological compensation system composed of government and enterprises, the government is in the dominant position. The ecological compensation input of the government and enterprise will produce social reputation, and the ecological compensation of enterprise will also produce advertising effect. Consumer demand will be affected by social reputation and advertising effect. Then, the compensation strategies of the government and enterprise are analyzed by constructing the differential game model. The research shows that under certain conditions, the cost-sharing mechanism can realize the Pareto improvement of the benefits of government, enterprise and the whole system. Under the cooperative mechanism, the benefit of the government, enterprise and the whole system is optimal. Finally, the validity of the conclusion is verified by case analysis, and the sensitivity analysis of the relevant parameters is carried out. The conclusion can provide reference for government to establish sustainable watershed ecological compensation mechanism.

Study on the quantification of ecological compensation in a river basin considering different industries based on water pollution loss value.

The study on the quantification of ecological compensation (eco-compensation) in a river basin can help to make environmental protection more compatible with ecological construction. In this paper, the upstream and downstream of the river basin were treated as the subjects and objects of eco-compensation, and the mechanism of eco-compensation was clarified. The emergy analysis theory (EMA) was used to calculate the values of water resources in sub-industries (agriculture, industry, life, and recreation). The pollution loss rate theory (PLR) was adopted to calculate the water pollution loss rate in sub-industries. According to the value of water resources and pollution loss rate in sub-industries, combined with the water consumption of sub-industries in the river basin, the Ecological Compensation Quantification Model of Sub-industries (ECQ-Is Model) was constructed. Under the guidance of the aforementioned theory and model, a comprehensive research was conducted on the Xiaohong River. The results showed that the eco-compensation values of the upstream area, industry, and agriculture in the river basin were higher. Therefore, it is essential that the water resources in the Xiaohong River basin be well conserved and managed. In addition, the research results point out the direction for water pollution control, which includes promoting the coordinated development of the upstream and downstream, and maximizing the ecological benefits of the river basin.

Socioeconomic, agricultural, and individual factors influencing farmers' perceptions and willingness of compost production and use: an evidence from Wadi al-Far'a Watershed-Palestine.

In Palestine, open dumping and/or burning the waste, including agricultural waste, are prevalent practices resulting in emitting leachate and acidifying greenhouse gases. Composting the agricultural waste can reduce emissions and provide 'compost' as an organic fertilizer and soil amendment; yet, it has not been implemented at the national level. To develop a local marketing strategy for compost, this study views a need to identify farmers' perceptions and willingness of compost production and use in agriculture and examine various socioeconomic, agricultural, and individual factors shaping them. The case of Wadi al-Far'a watershed (WFW) is investigated, where farmers practice inappropriate waste disposal and overuse of agrochemicals. A semi-structured questionnaire is administered to 409 farmers through face-to-face interviews. Descriptive statistics, bivariate analyses, Chi-square test, and binary logistic regression are used for data analysis. High acceptance level (84%) is disclosed among farmers in WFW for the hypothetical idea of producing and using compost. Farmers also have high, yet lower, willingness level (63.6%) of the more salient option of producing compost themselves and using it in agriculture. Tenure systems, large cultivated areas, rainfed irrigation, and lack of access to training sessions inhibit farmers' acceptance of the idea of compost production (overall p value = 0.000). Large cultivated areas and rainfed irrigation is also associated with farmers' unwillingness to produce compost, besides high household monthly income, animal or mixed animal-plant farming, experience in compost production, and use of pesticides (overall p value = 0.000).

Effluent trading planning and its application in water quality management: A factor-interaction perspective.

In this study, a Bayesian risk-induced interval stochastic modeling framework (BRISF) is proposed for planning effluent trading program among point and nonpoint sources as well as identifying interactions of important trading factors under system risk. BRISF incorporates nutrient fate modeling with soil and water assessment tool (SWAT), Bayesian inference with random walk Metropolis algorithm (RWM), and constraint-violation risk-based two-stage stochastic programming (CRTSP) within a general framework. Bayesian inference is employed for uncertainty analysis of SWAT model parameters and uncertain prediction of nutrient loadings; this process provides the random inputs for optimization process. CRTSP is capable of dealing with multiple uncertainties in modeling effluent trading program as well as system risk of environmental allowance violation. BRISF is applied to a real case of Xiangxihe watershed in China for water quality management. Solutions for optimal trading scheme corresponding to different risk levels are generated. Thousands of scenarios are examined to analyze the individual and interactive effects of trading ratios and treatment rates on trading system. Comparison between cross-industry and intra-industry effluent trading scheme is also conducted. It is proved that cross-industry trading would bring about higher benefit with reduced pollution loading; cross-industry effluent trading scheme would be recommended to achieve optimal water quality management and system benefit.

Category-bounded emotional enhancement: spillover effects in the valuation of public goods.

We examined whether enhancing (vs. not enhancing) the emotionality of a referent public good influences the subsequent valuation of a target public good. We predicted that it would and that the directionality of its impact would depend on a fundamental cognitive process - categorisation. If the target and referent goods belong to the same domain, we expected that the effect on the target would be in the same direction as the emotional enhancement of the referent (assimilation effect). However, if the target and referent goods belong to different domains, we expected that the effect on the target would be either negligible or in the opposite direction to that of the emotional enhancement of the referent (null or contrast effect). In Experiment 1 we examined the impact of emotionally enhancing a referent public good on feelings towards a target public good, whereas in Experiment 2 on the willingness to contribute towards a target public good. The results support the predicted interaction, which was driven by an assimilation effect for same-domain goods and a null effect for different-domain goods. In doing so, the present findings highlight the interplay between cognition and emotion in the valuation of public goods. We discuss theoretical and practical implications.

Study of ecological compensation in complex river networks based on a mathematical model.

Transboundary water pollution has resulted in increasing conflicts between upstream and downstream administrative districts. Ecological compensation is an efficient means of restricting pollutant discharge and achieving sustainable utilization of water resources. The tri-provincial region of Taihu Basin is a typical river networks area. Pollutant flux across provincial boundaries in the Taihu Basin is hard to determine due to complex hydrologic and hydrodynamic conditions. In this study, ecological compensation estimation for the tri-provincial area based on a mathematical model is investigated for better environmental management. River discharge and water quality are predicted with the one-dimensional mathematical model and validated with field measurements. Different ecological compensation criteria are identified considering the notable regional discrepancy in sewage treatment costs. Finally, the total compensation payment is estimated. Our study indicates that Shanghai should be the receiver of payment from both Jiangsu and Zhenjiang in 2013, with 305 million and 300 million CNY, respectively. Zhejiang also contributes more pollutants to Jiangsu, and the compensation to Jiangsu is estimated as 9.3 million CNY. The proposed ecological compensation method provides an efficient way for solving the transboundary conflicts in a complex river networks area and is instructive for future policy-making.

Relationship between urbanisation and pollutant emissions in transboundary river basins under the strategy of the Belt and Road Initiative.

Urbanisation has increased the discharge of pollutants, altered water flow regimes, and modified the morphology of transboundary river basins. All these actions have resulted in multiple pressures on aquatic ecosystems of transboundary river basins, undermining the healthy development of their aquatic ecosystems as well as impairing the sustainable economic and social development associated therewith. Quantifying the relationship between socio-economic factors, and water environment systems, and understanding the multiple pressures in their combined impact on environmental fairness of transboundary river basins is challenging, and it is crucial to the strategic planning of the Belt and Road strategy. Here, the Songhua River basin, which is the largest branch of the China-Russia boundary river is taken as the study area. The Environmental Kuznets Curve (EKC) model, which is coupled with the integrated model (pollutant emissions intensity, pollutant discharge efficiency, and pollutant emissions per capita), are used to reveal the spatio-temporal variations in regional pollutant emissions in the SRB. The results show that the features of the EKC are present in the pollutant emissions during economic development of the SRB. It also demonstrates that the turning point value of the EKC appeared when the GDP per capita is around ¥40,000 (CNY) in the SRB, which means that the pollutant emissions show an increasing trend, when the GDP per capita is less than ¥40,000. Our findings could contribute to a better understanding of the coupling relationship between pollutant emissions in transboundary river basins and urbanisation process in water stress to help address water allocation problems.

Evaluating the Hydrologic Performance of Low Impact Development Scenarios in a Micro Urban Catchment.

As urbanization progresses, increasingly impervious surfaces have changed the hydrological processes in cities and resulted in a major challenge for urban stormwater control. This study uses the urban stormwater model to evaluate the performance and costs of low impact development (LID) scenarios in a micro urban catchment. Rainfall-runoff data of three rainfall events were used for model calibration and validation. The pre-developed (PreDev) scenario, post-developed (PostDev) scenario, and three LID scenarios were used to evaluate the hydrologic performance of LID measures. Using reduction in annual runoff as the goal, the best solutions for each LID scenario were selected using cost-effectiveness curves. The simulation results indicated that the three designed LID scenarios could effectively reduce annual runoff volumes and pollutant loads compared with the PostDev scenario. The most effective scenario (MaxPerf) reduced annual runoff by 53.4%, followed by the sponge city (SpoPerf, 51.5%) and economy scenarios (EcoPerf, 43.1%). The runoff control efficiency of the MaxPerf and SpoPerf scenarios increased by 23.9% and 19.5%, respectively, when compared with the EcoPerf scenario; however, the costs increased by 104% and 83.6%. The reduction rates of four pollutants (TSS, TN, TP, and COD) under the MaxPerf scenario were 59.8-61.1%, followed by SpoPerf (53.9-58.3%) and EcoPerf (42.3-45.4%), and the costs of the three scenarios were 3.74, 3.47, and 1.83 million yuan, respectively. These results can provide guidance to urban stormwater managers in future urban planning to improve urban water security.

Simple rules can guide whether land- or ocean-based conservation will best benefit marine ecosystems.

Coastal marine ecosystems can be managed by actions undertaken both on the land and in the ocean. Quantifying and comparing the costs and benefits of actions in both realms is therefore necessary for efficient management. Here, we quantify the link between terrestrial sediment runoff and a downstream coastal marine ecosystem and contrast the cost-effectiveness of marine- and land-based conservation actions. We use a dynamic land- and sea-scape model to determine whether limited funds should be directed to 1 of 4 alternative conservation actions-protection on land, protection in the ocean, restoration on land, or restoration in the ocean-to maximise the extent of light-dependent marine benthic habitats across decadal timescales. We apply the model to a case study for a seagrass meadow in Australia. We find that marine restoration is the most cost-effective action over decadal timescales in this system, based on a conservative estimate of the rate at which seagrass can expand into a new habitat. The optimal decision will vary in different social-ecological contexts, but some basic information can guide optimal investments to counteract land- and ocean-based stressors: (1) marine restoration should be prioritised if the rates of marine ecosystem decline and expansion are similar and low; (2) marine protection should take precedence if the rate of marine ecosystem decline is high or if the adjacent catchment is relatively intact and has a low rate of vegetation decline; (3) land-based actions are optimal when the ratio of marine ecosystem expansion to decline is greater than 1:1.4, with terrestrial restoration typically the most cost-effective action; and (4) land protection should be prioritised if the catchment is relatively intact but the rate of vegetation decline is high. These rules of thumb illustrate how cost-effective conservation outcomes for connected land-ocean systems can proceed without complex modelling.

Discharge permit market and farm management nexus: an approach for eutrophication control in small basins with low-income farmers.

The economic concerns of low-income farmers are barriers to nutrient abatement policies for eutrophication control in surface waters. This study brings up a perspective that focuses on integrating multiple-pollutant discharge permit markets with farm management practices. This aims to identify a more economically motivated waste load allocation (WLA) for non-point sources (NPS). For this purpose, we chose the small basin of Zrebar Lake in western Iran and used the soil and water assessment tool (SWAT) for modeling. The export coefficients (ECs), effectiveness of best management practices (BMPs), and crop yields were calculated by using this software. These variables show that low-income farmers can hardly afford to invest in BMPs in a typical WLA. Conversely, a discharge permit market presents a more cost-effective solution. This method saves 64% in total abatement costs and motivates farmers by offering economic benefits. A market analysis revealed that nitrogen permits mostly cover the trades with the optimal price ranging from $6 to $30 per kilogram. However, phosphorous permits are limited for trading, and their price exceeds $60 per kilogram. This approach also emphasizes the establishment of a regional institution for market monitoring, dynamic pricing, fair fund reallocation, giving information to participants, and ensuring their income. By these sets of strategies, a WLA on the brink of failure can turn into a cost-effective and sustainable policy for eutrophication control in small basins.

Seafood prices reveal impacts of a major ecological disturbance.

Coastal hypoxia (dissolved oxygen ≤ 2 mg/L) is a growing problem worldwide that threatens marine ecosystem services, but little is known about economic effects on fisheries. Here, we provide evidence that hypoxia causes economic impacts on a major fishery. Ecological studies of hypoxia and marine fauna suggest multiple mechanisms through which hypoxia can skew a population's size distribution toward smaller individuals. These mechanisms produce sharp predictions about changes in seafood markets. Hypoxia is hypothesized to decrease the quantity of large shrimp relative to small shrimp and increase the price of large shrimp relative to small shrimp. We test these hypotheses using time series of size-based prices. Naive quantity-based models using treatment/control comparisons in hypoxic and nonhypoxic areas produce null results, but we find strong evidence of the hypothesized effects in the relative prices: Hypoxia increases the relative price of large shrimp compared with small shrimp. The effects of fuel prices provide supporting evidence. Empirical models of fishing effort and bioeconomic simulations explain why quantifying effects of hypoxia on fisheries using quantity data has been inconclusive. Specifically, spatial-dynamic feedbacks across the natural system (the fish stock) and human system (the mobile fishing fleet) confound "treated" and "control" areas. Consequently, analyses of price data, which rely on a market counterfactual, are able to reveal effects of the ecological disturbance that are obscured in quantity data. Our results are an important step toward quantifying the economic value of reduced upstream nutrient loading in the Mississippi Basin and are broadly applicable to other coupled human-natural systems.

Management of unregulated agricultural nonpoint sources through water quality trading market.

Water quality trading (WQT) could be an innovative policy to incentivize farmers to implement best management practices (BMPs) for their activities. This study focused on assessment of involving unregulated agricultural nonpoint sources (NPS) into the WQT market in Gharesoo watershed in the west of Iran. It also proposes a methodology to determine location-based trading ratios as well as environmental penalty cost to achieve a more well-designed market structure. Trading activities in different scenarios were described by trading volume (TV), participation rate (PR), total exchanged value (TEV), and other market parameters in order to achieve a better comparison of market performance. Results showed that, by applying NPS to the Gharesoo watershed, total phosphorous (TP) trading market could increase TV, PR, and TEV up to 11, 1.7 and 7.5 times, respectively, depending on which level of BMPs are implemented by them. Additionally, it could save 29% of the total cost of implementing a TP total maximum daily load in this watershed compared to the 'command and control' approach. Furthermore, the agricultural sector could profit by $5.49 million (or $75/ha) by choosing solutions such as terrace systems and filter strips to register into the market. This profit can be allocated to the development of new agricultural technologies.

Joint pollution control in the Lake Tai Basin and the stabilities of the cost allocation schemes.

This paper provides insights into the allocation of benefits derived from joint wastewater treatment in the Lake Tai Basin of China and the acceptability and stability of different cost allocation schemes in a trans-jurisdictional water system context. First, the wastewater treatment cost function is estimated and coalition costs are compared to the cost of stand-alone wastewater treatment in each province. Second, two standard and five game theoretical cost allocation schemes are applied to the grand coalition. Results suggest that a cost savings of US $46.46 million can be obtained by forming a grand coalition. All allocation schemes were found to be acceptable. Results also suggest that both Shanghai and Jiangsu Province would prefer a proportional allocation scheme based on pollutant discharge, because it would offer them the largest cost savings. But this allocation scheme is the least stable one. Based on the criterion of stability, the Nash-Harsanyi scheme emerges as providing the optimal allocation. Finally, calculation of power and stability indexes suggests Jiangsu Province as an agent is critical to the success of grand coalition formation.

Towards tradable permits for filamentous green algae pollution.

Water pollution permit systems are challenging to design and implement. Operational systems that has maintained functionality remains few and far between, particularly in developing countries. We present current progress towards developing such a system for nutrient enrichment based water pollution, mainly from commercial agriculture. We applied a production function approach to first estimate the monetary value of the impact of the pollution, which is then used as reference point for establishing a reserve price for pollution permits. The subsequent market making process is explained according to five steps including permit design, terms, conditions and transactional protocol, the monitoring system, piloting and implementation. The monetary value of the impact of pollution was estimated at R1887 per hectare per year, which not only provide a "management budget" for filamentous green algae mitigation strategies in the study area, but also enabled the calculation of a reserve price for filamentous green algae pollution permits, which was estimated between R2.25 and R111 per gram filamentous algae and R8.99 per gram at the preferred state.

Pollution control costs of a transboundary river basin: Empirical tests of the fairness and stability of cost allocation mechanisms using game theory.

With rapid economic growth, transboundary river basin pollution in China has become a very serious problem. Based on practical experience in other countries, cooperation among regions is an economic way to control the emission of pollutants. This study develops a game theoretic simulation model to analyze the cost effectiveness of reducing water pollutant emissions in four regions of the Jialu River basin while considering the stability and fairness of four cost allocation schemes. Different schemes (the nucleolus, the weak nucleolus, the Shapley value and the Separable Cost Remaining Benefit (SCRB) principle) are used to allocate regionally agreed-upon water pollutant abatement costs. The main results show that the fully cooperative coalition yielded the highest incremental gain for regions willing to cooperate if each region agreed to negotiate by transferring part of the incremental gain obtained from the cooperation to cover the losses of other regions. In addition, these allocation schemes produce different outcomes in terms of their fairness to the players and in terms of their derived stability, as measured by the Shapley-Shubik Power Index and the Propensity to Disrupt. Although the Shapley value and the SCRB principle exhibit superior fairness and stabilization to the other methods, only the SCRB principle may maintains full cooperation among regions over the long term. The results provide clear empirical evidence that regional gain allocation may affect the sustainability of cooperation. Therefore, it is implied that not only the cost-effectiveness but also the long-term sustainability should be considered while formulating and implementing environmental policies.

Waste load equilibrium allocation: a soft path for coping with deteriorating water systems.

Waste load allocation is always regarded as another efficient approach comparing with the technology-based approach to improve the water quality. This paper proposes a bi-level multi-objective optimization model for optimally allocating the waste load of a river basin incorporating some concerns (i) the allocation equity from the regional authority, (ii) maximal benefits from the subareas along the river, and (iii) the Stackelberg-Nash-Cournot equilibrium strategy between the upper and lower decision makers. Especially, a novel Gini coefficient for measuring the load allocation equity is defined by considering the economic level and waste water quantity. The applicability and effectiveness of the proposed model is demonstrated through a practical case based on the Tuojiang River, which is a typical basin with diversified industrial waste discharges in western China. Some operational suggestions are developed to assist the decision makers' cope with deteriorating water systems.