Narrow Results

Efficiency analyses of public services, such as water resource management, is in vogue owing to investments financed by taxpayers. However, in regulated sectors, i.e., without competition, data envelopment analysis (DEA) results for decision-making are questionable. Indeed, DEA is sensitive to the data, inputs, and outputs chosen by the researcher and can be highly influenced by outliers. There is no space for specialization: a decision-making unit (DMU) may be inefficient generally but efficient in one particular activity (output). Previous studies on DEA of water efficiency use second-stage analysis with exogenous factors, i.e., not controlled by management, making empirical applications unfeasible. In addition, models do not reflect changes in the specialization of DMUs through time caused by financial crises or lack of infrastructure. DEA visualization combines the standard DEA analysis with multivariate statistical methods. In this chapter, water supply and quality in 31 provinces of China are benchmarked for 2020. The results show nine efficient provinces for the traditional DEA model (all the variables). Other provinces become efficient when considering infrastructure for water supply versus water quality (few pollutants). Two provinces are efficient due to a surplus of natural water resources (overcapacity) in relation to their population, allowing for high-quality water provision, which may be transferred to regions with high water scarcity.

Although agricultural production contributed about 10% of all greenhouse gas emissions in the United States in 2019, existing agricultural practices are capable of making the sector carbon neutral. Whether American agriculture will ultimately achieve carbon neutrality is ultimately a question of political will, not a scientific one. Given the right policy environment, farms and ranches will be able to cut their emissions and use their land to sequester carbon, while becoming more climate resilient, productive, and profitable…

This paper investigates the hydrochemical setting of Lake Luoma to detect temporal and spatial trends. Physical, organic and nutritional parameters were the main variables to be evaluated. It was found that pH and BOD were almost the same in Suqian and Xuzhou. DO gradually declines in Suqian but increases in Xuzhou. The cluster analysis showed that it could be divided into 3 classes: April and October, January and February, and all other months. This is mainly related to the flood period including mean-flow period, lowflow period and high-flow period. The extensive investigation found that the core water quality parameters of COD_Mn, BOD₅, Se, Cr⁶⁺, VP, S and FE were significantly different between the two monitoring stations.

Stormwater is water that originates from precipitation events such as rainfall, snowmelt, and activities such as watering lawns, washing cars, and draining pools. The main goal of stormwater management is to maintain health of environment as well as provide opportunities for human uses by extenuating the effect of urban development. This chapter divided into three main topics: introduction of stormwater (history, stormwater pollution, and stormwater management), important of stormwater management, and stormwater design.

In the last few years, there has been a significant increase in population growth all over the world. This has been accompanied by intensive urbanization, an increase in industrial activities and a greater exploitation of cultivable land. These transformations have provoked a huge increase both in the quantity of discharge and the range of pollutants that could reach the aquatic ecosystems and deteriorating water quality. This review covers the aspects of water quality and impact assessment of aquatic pollution.

Our planet is characterized by large volumes ofwater that cover nearly three-quarter of the earth's surface. The immense part of this water is salty, and most of the freshwater is stored as groundwater or frozen in glaciers. Environment is constantly changing and anthropogenic activities are responsible for many of the environmental problems facing currently. This chapter addresses many of the present-day water quality problems from an international perspective, covering critical issues such as river and lake contamination, quality assessments, and some remedial measures to minimize pollution.

From the beginning of the reform and open door policy period, in 1978, to the present moment, China has consistently subordinated the importance of environmental protection to the pursuit of rapid economic growth in the name of constructing a socialist modernized state. Remarkable achievements in economic development have been made in the last three decades, and people's living standards, in material terms, have been vastly improved, but China has paid a very heavy price, in environmental terms, for such gains. Confronted with a widening spectrum of problems manifesting rapid environmental deterioration, major initiatives and measures have been repeatedly undertaken by the Central government to improve the efficacy of the country's environment protection apparatus. This chapter reviews the challenges encountered, and progress made, in the field of environmental protection, tracing the impacts of rapid industrial and urban growth on the country's environmental contours and ecological landscape. We argue that, despite of the pro-environment actions undertaken by the Central government, the prospect for a quick reversal of the current trends of environmental degradation remains slim because such efforts have always been resisted or even negated by local governments bent on pursuing economic growth at the cost of environmental protection. Unless China's political culture is reformed to allow a greater degree of transparency in local governance matters and that the implementation of environmental policies and programs is effectively and vastly strengthened, the country will be hard pressed to achieve even its modest environmental targets in the foreseeable future.

In this study, a microcosm experiment is set up to investigate the die-off response of Enterococci to the range of environmental conditions in Hong Kong. Four local strains of Enterococcus faecium and Enterococcus faecalis were selected from wastewater samples from three representative sewage treatment plants in Hong Kong. Their die-off rates under different combinations of light intensity, salinity, nutrient and temperature were determined from the rate of change of Enterococci concentration. The relative influence and interaction of the four factors were studied with 3D response surface analysis. It is observed that 1) Light intensity is the primary factor governing the elimination of Enterococci; 2) Enterococci has high tolerant to salinity at low light intensity, but its tolerance reduces significantly with the increase of light intensity; 3) Nutrient does not enhance the survival of Enterococci cells under light condition; 4) The die-off response of Enterococci to temperature follows a sag curve. Based on the results, a die-off equation is constructed for Enterococci, which will be useful for future water quality management.

BP neural network can achieve arbitrary nonlinear mapping of the input to the output, so it is extensively adopted in intelligent control, image recognition, hydrological predicting and water-resource quantity evaluation, etc., has stronger features of mapping, classification, functional fitting. This paper chooses the water quality of Lanzhou section of Yellow river as example by use of BP model to forecast the water quality. It is well verified that BP network model can reach the purposes of early warning and predicting.

In this study, a novel aquatic eutrophication model was presented by coupling the Environmental Fluid Dynamics Code (EFDC) and three-dimensional eutrophication models (CE-QUAL-ICM). The meteorological factors (wind speed, evaporation and radiation) and emergent plant factors (spatial distribution, density, height and diameter) were substantially accounted for in the model to reflect the effects of adsorption and degradation of pollutants by emergent plant and the changes of bottom stress and flow field. The proposed model was used to simulate the inter-annual and seasonal changes of water quality in Wuliangsuhai Lake which is a shallow eutrophication lake surrounded by the emergent plant in Inner Mongolia, China during 2004–2009. The simulated concentrations of total nitrogen, total phosphorus, chlorophyll-a and chemical oxygen demand with consideration of the presence of emergent plants were satisfactorily agreement with the measured ones. The simulation results indicate that it is very important to reduce the pollutant load into the lake, which can directly change the concentration of the water quality in the lake area. The information of water quality in shallow and dense emergent plants covered aquatic area where in-site observation is unavailable could be obtained from the model. Therefore, it appears that the developed model is an effective approach to simulate water quality of shallow grass-algae lakes, and can be used as a useful water environmental planning and management tool in these regions.