Point Pollution Research Articles

Simulation of Non-Point Pollutants Evolution in Coastal Plain Island-A Case Study of Chongming Island

The coastal plain region usually shows the agricultural dominated industry mode, so more and more attention is paid to non-point pollutants discharge. In this study, the method for assessing the influence of non-point pollutants discharge on river water quality is probed which is concluded as follows: (1) Considering the costal plain island is characterized as nearly even elevation, the conventional gravitational runoff confluence method based on eight-point gravitational flowing directions (D8) is unable to compute the runoff confluence received by the surrounding rivers, so a new method of triangular confluence based on three-points of grid center and the river segments is presented. Further the equations of non-point pollutants loads estimation and non-point pollutants confluence on rivers are presented. (2) The integration mode of non-point pollutants model and river water quality model is presented so as to further assess the non-point pollutants contribution to river water quality. (3) With the Chongming Island, the third largest island in China, as an example, the above-mentioned equations are specified. For this island, the non-point pollutants loads are estimated and linked to the developed water quality model of the river network in the island, and further the non-point pollution evolution in river network is simulated. In this scenario, the non-point pollution contribution to river water quality over the whole island is clearly displayed, and the area where the river water quality is seriously influenced by non-point pollutants discharge is distinctly depicted. This scenario also shows the water quality contribution ratio of non-point pollution to point pollution can be in the range of 55.5% to 44.5% which proves the importance of non-point pollution control in costal plain islands.

Role of rural solid waste management in non-point source pollution control of Dianchi Lake catchments, China

In recent years, with control of the main municipal and industrial point pollution sources and implementation of cleaning for some inner pollution sources in the water body, the discharge of point source pollution decreased gradually, while non-point source pollution has become increasingly distressing in Dianchi Lake catchments. As one of the major targets in non-point source pollution control, an integrated solid waste controlling strategy combined with a technological solution and management system was proposed and implemented based on the waste disposal situation and characteristics of rural solid waste in the demonstration area. As the key technology in rural solid waste treatment, both centralized plant-scale composting and a dispersed farmer-operated waste treating system showed promise in rendering timely benefits in efficiency, large handling capacity, high quality of the end product, as well as good economic return. Problems encountered during multi-substrates co-composting such as pathogens, high moisture content, asynchronism in the decomposition of different substrates, and low quality of the end product can all be tackled. 92.5% of solid waste was collected in the demonstration area, while the treating and recycling ratio reached 87.9%, which prevented 32.2 t nitrogen and 3.9 t phosphorus per year from entering the water body of Dianchi Lake after implementation of the project.

Groundwater Pollution of the Quaternary Aquifer in Northern United Arab Emirates

Natural conditions and human activities have caused serious quality degradation of the Quaternary aquifer in the north of the United Arab Emirates (UAE). The aquifer within Ajman City is unconfined, receiving limited recharge (12 542 m3/day) from the east and large pollutants flux (4,800 m3/day) from land surface. Field survey and laboratory analyses revealed anomalies in groundwater salinity (TDS), total hardness (TH), dissolved oxygen (DO), cations (Ca2+, Mg2+, Na+ and K+), anions (\({\text{HCO}}_3^ - \), \({\text{SO}}_4^{2 - } \), Cl− and \({\text{NO}}_3^ - \)) and trace elements (Fe, Pb, Cd and Cr), which can be correlated to point and non-point pollution sources. Concentrations of trace elements are more responsive to anthropogenic sources than natural ones. High Fe and Pb levels were measured close to the untreated sewage disposal site, while high Cd and Cr contents were observed near hospitals and clinics. Iso-concentration maps of salinity and major ions, in addition to hydrochemical profiles were used to define the seawater–groundwater interface in Ajman City. The potentiometric surface map of the Quaternary aquifer within the study area shows that groundwater flows from the east towards the Arabian Gulf in the west. The proposed landfill site is suitable because it lies within a topographic low, receiving groundwater flow from all directions.

Changes in species richness of vascular plants under the impact of air pollution: a global perspective

ABSTRACTAim To investigate the general pattern of changes in species richness and diversity of vascular plants due to environmental contamination and associated habitat changes imposed by point polluters, and identify the sources of variation in the response of plant communities to industrial pollution.Location Global.Methods We collected species richness and diversity data from 86 studies that were conducted around 60 atmospheric point polluters worldwide and reported in 95 papers (published in 1953–2007). We used meta‐analysis to search for a general effect and to compare between polluter types and plant groups, and linear regression to describe the latitudinal gradient and to quantify relationships between pollution and effect size.Results Although the species richness of vascular plants generally decreased with pollution, the effects were not uniform across the studies. Polluters that cause soil acidification imposed a stronger detrimental effect on plant diversity than industries whose emissions increased soil pH. An overall adverse effect was primarily due to the contribution of non‐ferrous smelters and aluminium plants; the effects of other SO2‐emitting industries were less detrimental, albeit negative, and the effects of chemical plants, fertilizer factories and cement industries did not differ from zero. Longevity of the pollution impact only made a slight contribution to the detected variation, while adverse effects increased with increase in pollution load.Main conclusions This study is the first demonstration of geographical variation in the responses of plant communities to aerial emissions: adverse effects increased from high to low latitudes, and this pattern was explained primarily by increases in both the diversity of original (undisturbed) communities and mean summer temperatures. The latter result suggests that under a future warmer climate the existing pollution loads may become more harmful. Model calculations indicate that a detectable depauperation of plant communities is unlikely if the polluter emits < 1500 t of SO2 annually.

From a water resource to a point pollution source: the daily journey of a coastal urban stream

The aim of this study was to understand how a stream ecosystem that flows from its fountainhead to its mouth inside a city, changes from a water resource to a point pollution source. A multidisciplinary descriptive approach was adopted, including the short-term temporal and spatial determination of physical, chemical, biological and ecotoxicological variables. Results showed that water quality rapidly decreases with increasing urbanization, leading the system to acquire raw sewage attributes even in the first hundred meters after the fountainheads. Despite the tidal circulation near the stream mouth being restricted by shallowness, some improvement of the water quality was detected in this area. The multidisciplinary evaluation showed to be useful for obtaining a more realistic understanding of the stream degradation process, and to forecast restoration and mitigation measures.

Remote Sensing Techniques to Detect Surface Water Quality Constituents in Coastal and Inland Water Bodies from Point or Non Point Pollution Sources

Remote Sensing Techniques to Detect Surface Water Quality Constituents in Coastal and Inland Water Bodies from Point or Non Point Pollution Sources

Does Impact of Point Polluters Affect Growth and Reproduction of Herbaceous Plants?

Investigation of nine herbaceous species collected around five polluters in northwestern Russia (nickel–copper smelters at Monchegorsk and Nikel, ore-roasting factory at Zapolyarnyy, aluminium smelter in Kandalaksha, and iron pellet plant at Kostomuksha) demonstrated that effects of pollution on plant growth were rarely significant in individual analyses. However, meta-analysis revealed decrease in plant size, in terms of height and leaf length; simultaneous increase in the number of leaves and flowers/inflorescences may compensate for this decline, thus the biomass of aboveground plant parts did not change. This result contrasts numerous experimental studies that generally demonstrate adverse effects of various pollutants on growth and reproduction of herbaceous plants, hinting that the effects detected in short-term experiments are of limited value for predicting performance of plant individuals surviving in polluted ecosystems. Changes in growth and reproduction of plants persisting under chronic pollution are minor presumably due to development of pollution tolerance and adaptation to altered environmental conditions.

Bioaccessibility of metals in urban playground soils

Children ingest soil. The amount ingested varies with the child's behaviour, and daily ingestion rates have been calculated to be between 39 and 270 mg day− 1. During play, children ingest soil both involuntarily and deliberately, and it can be assumed that the latter may result in ingestion of a larger soil particle size fraction and a larger soil mass than the former. Measurements of soil metal contents commonly display the total metal content, where soil sieved to < 2 mm has been digested with strong acids. This procedure does not consider differences in metal contents between size fractions or ingested soil masses. Moreover, it does not consider the difference between bioaccessible and total metal content, possibly resulting in an incorrect evaluation of the potential health risks from soil intake. Intervention and guideline values are commonly calculated via tolerable daily intake values, in turn derived from toxicological studies where the contaminant is administered to a test animal in feed or water. It is then assumed that the bioavailability of a contaminant in soil equals the bioavailability in the matrix used in the toxicology study. However, the complexity and heterogeneity of soil often results in a lower bioavailability than from food or water. The current study investigated the bioaccessibility of soil As, Cd, Cr, Ni and Pb from two different particle size fractions representing deliberate (< 4 mm) and involuntary (< 50 μ m) ingestion, as well as from two different soil masses representing deliberate soil intake; 2 g for a child with pica behaviour and 0.6 g for a non-pica child. The bioaccessibility was investigated using an in vitro digestion model and urban playground soils collected away from any point pollution sources. The bioaccessibility (%) of the different metals increased in the order Ni = Cr = Pb < < As < Cd for the involuntary ingestion (< 50 μ m, 0.6 g) and pica behaviour (< 4 mm, 2 g) scenarios, while the deliberate non-pica scenario (< 4 mm, 0.6 g) displayed increasing bioaccessibility in the order Ni = Cr < Pb < As = Cd. The difference in bioaccessibility between elements was concluded to be due to differences in origin, sorption behaviour and pH dependence. The study also found that the bioaccessible amount of metal in ingested soil is not always related to particle size or to soil mass in soils with low contaminant levels. Factors such as pH dependence of the metal and the soil's clay content are also significant in determining bioaccessibility.

Diffuse pollution abatement – a key component in the integrated effort towards sustainable urban basins

Water bodies are highly stressed by overdrafts of water for many purposes upstream and in the cities, and effluent domination and excessive point and diffuse pollution downstream. Pollution is also caused by the urban landscape which prefers impervious rather than porous surfaces; fast-conveyance infrastructure rather than "softer" approaches like ponds and vegetation; and stream channelization instead of natural stream courses, buffers and floodplains, and development in the floodplains. In future, the comprehensive and complex problems of urban pollution must be solved within the framework of the total hydrological cycle concept. This provides a new impetus to diffuse pollution management in urban areas. The best management practices that have been developed in the past could become key components of the new urban total hydrological cycle paradigm for solving the water shortage and pollution problems in an integrated manner, and making the urban systems hydrologically and ecologically sustainable. The paradigm will include landscape changes (less imperviousness, more green space used as buffers and groundwater recharge) as well application of the best management practices that provide water conservation, storage and reuse.

Atmospheric deposition and isotope biogeochemistry of zinc in ombrotrophic peat

Zinc isotope ratios were measured in the top sections of dated ombrotrophic peat cores in Finland to investigate their potential as proxies for atmospheric sources and to constrain post depositional processes affecting the geochemical record. The peat deposits were located in Hietajärvi, a background site well away from any point pollution source and representing ‘background’ conditions, in Outokumpu, next to a mining site, and in Harjavalta, next to a smelter. Measured total concentrations, calculated excess concentrations and mass balance considerations suggest that zinc is subjected to important biogeochemical cycling within the peat. Significant isotopic variability was found in all three peat bogs, with heavier zinc in the deeper and lighter zinc in the upper sections. Isotope ratios and concentrations correlated in the two peats located next to dominant point sources, i.e. the smelting and mining site, suggesting that zinc isotopes trace pollution sources. Concentration and isotope peaks were offset from the period of mining and smelting activity, supporting migration of zinc down the profile. The δ 66Zn JMC (where δ 66Zn = [( 66Zn/ 64Zn) sample/( 66Zn/ 64Zn) JMC-standard − 1] × 10 3) of the top section sample at the remote Hietajärvi site was 0.9‰ and we suggest this represents the regional background isotope signature of atmospheric zinc. The deeper sections of the peat cores show isotopically heavier zinc than any potential atmospheric source, indicating that post depositional processes affected the isotopic records. The large variations encountered (up to 1.05‰ for δ 66Zn) and Rayleigh modelling imply that multiple fractionation of zinc during diagenetic alterations occurs and nutrient recycling alone cannot explain the fractionation pattern. We propose that zinc isotopes are amenable to identify different atmospheric zinc sources, including zinc derived from anthropogenic activities such as mining and smelting, but multiple biogeochemical processes seriously affect the record and they need to be evaluated and assessed carefully if zinc isotopes are used in terrestrial paleorecords.

Assessing of biotic integrity of the fish community in a heavily impacted segment of a tropical river in Brazil

A index of biotic integrity (IBI) was applied to assess the ecological health at seven sites of ca. 338 km extension of the Paraíba do Sul river, in bracketing a large urban-industrial complex. The aim was to evaluate the index response to changes in environmental quality during two seasons (winter/dry versus. summer/wet). Eight metrics were selected to IBI in three categories: 1) species richness and habitat composition; 2) indicator species; and 3) trophic structure. The IBI, based on the least impacted regional condition, showed the highest value at the most upstream site (Queluz=km 0) - Acceptable, then decreasing downstream and reaching the lowest record at Volta Redonda (km 125) - Impacted; afterwards there was an increasing quality toward the most downstream sites until reaching better scores at Além Paraíba (km 338) - Moderate Impacted/ Acceptable. During the winter/dry seasons a clearer spatial trend was detected when compared with oscillations in summer/wet. The IBI proved to be a suitable tool to evaluate environmental quality in this tropical and very altered large river, since it was sensitive to non-source point pollution changes, which occurred all over the studied area.

Surface and groundwater quality in the northeastern region of Buenos Aires Province, Argentina

This work studies the water quality of the Pergamino–Arrecifes River zone in the Rolling Pampa, northeast Buenos Aires Province, Argentina. Temperature, pH, specific conductivity, Na, K, Mg, Ca, SO 4 2 - , Cl −, HCO 3 - , NO 3 - , Si, Ag, Al, As, B, Ba, Be, Br, Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Mo, Ni, P, Pb, Se, Tl, U, V, Zn, and the environmental stable δ 18O and δ 2H isotope ratios were determined in 18 sampling stations. Natural and anthropogenic features influence surface and groundwater quality. Point pollution sources (septic wells and other domestic and farming effluents) increase the nitrate concentration. The values of pH, NO 3 - , Al, As, B, Fe, and Mn exceed the respective Argentine reference thresholds in different sampling stations for human drinking water; B, Mo, U, and V for irrigation; and V and Zn for cattle consumption.

Assessment of point and non-point pollution associated with the power generation sector in South Africa

Access to water and water availability remains a key factor in ensuring the sustainability of development in Southern Africa. The need for guidelines to improve management of this valuable resource, and to regulate pollutant discharge, is therefore of national interest. A new and growing threat to our natural water resources is non-point source (NPS) pollution. The important distinction between point pollution and NPS pollution is that the latter is difficult to identify and the entry point of contamination to resources is diffuse and not limited to a single location. NPS pollution associated with power generation includes, but is not limited to, atmospheric deposition resulting from emissions (air and water), leachate from coal storage piles and runoff from impervious areas which are covered with dust fallout from coal and ash handling operations. Emissions of primary concern are sulfur, nitrogen and mercury.

Identification of anthropogenic influences on water quality of rivers in Taihu watershed

Surface water bodies are progressively subjected to stress as a result of anthropogenic activities. This study assessed and examined the impact of human activities on spatial variation in the water quality of 19 rivers in the Taihu watershed. Concentrations of physico-chemical parameters of surface water quality were determined at the mouth of each river during the period of 2000–2004. Multivariate statistical techniques were applied to identify characteristics of the water quality in the studied rivers. The results showed that rivers strongly influenced by household wastewater have the highest concentrations of nutrients (TN and TP). Moreover rivers in the vicinity of a metropolis presented low dissolved oxygen (DO) levels. However organic-chemical pollution (petroleum and volatile phenolics) was identified with high localization. Two rivers influenced by sewage from industry and ships were distinguished from other rivers with high values of petroleum. The Taige channel a river located in Changzhou City that is strongly influenced by wastewater from industry was characterized with an extraordinarily high value of volatile phenolics. Rivers passing through countries especially through hilly countries were characterized with high DO contents and low nutrient and organic-chemical pollution suggesting that agriculture puts less pressure on water quality in adjacent rivers. Therefore more effort should be made in controlling point pollution to restore water quality in rivers adjacent to cities.

Budburst phenology of white birch in industrially polluted areas

Effects of environmental contamination on plant seasonal development have only rarely been properly documented. Monitoring of leaf growth in mountain birch, Betula pubescens subsp. czerepanovii, around a nickel–copper smelter at Monchegorsk hinted advanced budburst phenology in most polluted sites. However, under laboratory conditions budburst of birch twigs cut in late winter from trees naturally growing around three point polluters (nickel–copper smelter at Monchegorsk, aluminium factory at Kandalaksha, and iron pellet plant at Kostomuksha) showed no relationship with distance from the emission source. In a greenhouse experiment, budburst phenology of mountain birch seedlings grown in unpolluted soil did not depend on seedling origin (from heavily polluted vs. clean sites), whereas seedlings in metal-contaminated soil demonstrated delayed budburst. These results allow to attribute advanced budburst phenology of white birch in severely polluted sites to modified microclimate, rather than to pollution impact on plant physiology or genetics.

Mercury transformations in marine coastal sediments as derived from mercury concentration and speciation changes along source/sink transport pathway (Southern Baltic)

In this study the distribution of mercury in coastal marine sediments was investigated. Samples of surface sediments were collected from three areas in the southern Baltic. The Gdansk Basin was selected due to proximity to point sources, while the Arkona and the Bornholm Deeps – because they are distant from point sources. Both total concentration and solid speciation of mercury were measured. Sources, transport routes, and transformation of mercury in bottom sediments were assessed. Total concentrations varied in the range from 20 to 430 ng/g sediment d.w. The dominant forms of mercury were mercury sulphide (50% ± 10%), and mercury bound to both humins and mineral matrix (30% ± 20%). The Odra River seems to be the main source of mercury in the Arkona Deep, whereas diffuse sources contribute to the mercury in the sediments of the Bornholm Deep. In the Gdansk Basin, diversified sources seem to control the distribution of mercury. They include point pollution sources in the western part of the bay; the Vistula River – the main source of mercury in the central Gdansk Bay, its influence extending to the Gdansk Deep area. Sediments of the Gdansk Deep western slope receive mercury from the suspended matter of both the Vistula River and the currents from other coastal regions as well as aerial long-range transport. Mercury species undergo transformation in the course of transport to depositional basins – which leads to partial remobilization of mercury from the sediments.

Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995:_2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu, occupied TN 53% and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 30% and 16%, and sewerage in both forms of point source and non-point source are TN 31% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

Evaluation of uncertainty propagation into river water quality predictions to guide future monitoring campaigns

To evaluate the future state of river water in view of actual pollution loading or different management options, water quality models are a useful tool. However, the uncertainty on the model predictions is sometimes too high to draw proper conclusions. Because of the complexity of process based river water quality models, it is best to investigate this problem according to the origin of the uncertainty. If the uncertainty stems from input data or parameter uncertainty, more reliable results are obtained by performing specific measurement campaigns. The aim of the research reported in this paper is to guide these measurement campaigns based on an uncertainty analysis. The practical case study is the river Dender in Flanders, Belgium. First an overview of different techniques that give valuable information for the reduction of input and parameter uncertainty is given. A global sensitivity analysis shows the importance of the different uncertainty sources. Further an analysis of the uncertainty bands is performed to find differences in uncertainty between certain periods or locations. This shows that the link between periods with high uncertainty and specific circumstances (climatological, eco-regional, etc.) can help in gathering data for the calibration of submodels (e.g. diffuse pollution vs. point pollution).

Mercury in the topsoil and dust of Beijing City

Research on mercury concentration in the dust and topsoil of Beijing City reveals the following conclusions: mercury concentration in Beijing topsoil and dust is middle compared to other mercury concentration studies and varies greatly in different sampling spots. Mercury concentration in the topsoil is between 0.019mg·kg−1 and 0.966mg·kg−1, it is about 2.11 times and 12.08 times of mercury concentration background in Beijing soil respectively. Mercury concentration in Beijing dust has a range of 0.053 to 1.378mg·kg−1; the maximum mercury concentration in the Beijing dust in 2003 is about 2.2 times of that in 1992. These results show that mercury pollution in Beijing topsoil and dust are serious, and mercury tends to enrich in the dust compared to the adjacent topsoil. Mercury in topsoil and dust of Beijing City has obvious regional differentiation characteristics, which is highest in the center of Beijing City and lower away from the center to the suburbs. In detail, mercury concentration in the topsoil samples and dust samples are highest in Dongsi area and lowest in the blank spot. Mercury in Beijing's topsoil belonging to point pollution is mainly from local area; mercury in the dust belongs to non-point source pollution because the source of mercury in the dust is very complex. Natural factors and anthropological factors have certain effect on mercury concentration in the topsoil and dust, and anthropological factors have more effect. The results are very important to protect and enhance our environmental quality.

China’s Environmental and Developmental Issues in Transition

Wang Yi China’s Environmental and Developmental Issues in Transition CHINA HAS SEEN RAPID ECONOMIC DEVELOPMENT AS WELL AS SEVERE environmental degradation over the past two decades. Although the Chinese government has made a great effort to provide environmen­ tal protection, it has been stymied by China’s economic development pattern, which follows the traditional industrialization mode of low efficiency in resource use and considerable pollutant discharge. In other words, China achieved its rapid economic growth at the cost of deplet­ ing natural resources and environmental quality. Should comprehen­ sive and effective actions not be undertaken in the next 15 years, the pollution pressures will exceed China’s environmental carrying capac­ ity and lead to an irreversible environmental crisis. Should this occur, environmental issues would become not only the greatest obstacle to China’s achievement of a xiao kang society and undermine China’s international image,1 but would also have a severe effect on the global environment. THE ENVIRONMENTAL COSTS OF SOCIAL AND ECONOMIC DEVELOPMENT China’s environmental concerns are complex, regional, and chronic. China rapid economic development period began in the 1980s and the country has quickly passed through the development stages that have taken the developed countries a century. A fragile environment social research Vol 73 : No 1 : Spring 2006 277 and unbalanced regional development accompanied by an excessive population increase, a traditional development model, and a question­ able policy orientation have resulted in severe environmental damage. Environmental issues that should have been seen at different develop­ ment stages appeared simultaneously. The current environmental issues are significantly different from those in 1980s in terms of their type, scale, structure, and nature. The severity of the issues stems not only from the volume of pollutant discharge and the scale of the ecosystem degradation, but also from their complexity, and the threat and risk they pose. Their impacts on the ecosystem, human beings, economic devel­ opment, social stability, and national security are chronic. They have become major constrains on sustainable development and the peace­ ful rise of China in the world. The complexity of the environmental issues confronting China was not seen in the industrialization process that the developed countries underwent. A holistic and comprehensive approach is urgently needed to address these issues in China. A Fragile Natural Environment and Expanded Ecosystem Degradation Arid and semi-arid areas and mountainous land account for 52 percent and 65 percent, respectively, of China’s land area (the Qinghai-Tibetan Plateau, the Loess Plateau, and the Karst areas comprise, in order, 2 million, 640,000, and 900,000 square kilometers). The fragile environ­ ment finds it hard to support population and development pressures. Some human activities have led to decreased functionality of ecosys­ tems as well as severe and enlarged ecological degradation. As a result, the area suffering water and soil erosion totals 3.56 million square kilometers or 37 percent ofnational land. Desertification affects some 1 million square kilometers (SEPA, 2004). In the 1970s, around 1,560 square kilometers of land was desertified annually and in the 1990s it increased to 3,436 square kilometers. The forest cover­ age in China is lower than that of the world average. The age struc­ ture of forest coverage is unhealthy, with primeval forest making up less than 10 percent. The quality and ecological functionality of forests 278 social research are decreasing. The area available for harvest is also being reduced. A few other remarkable facts: 62 percent of grassland was degraded at the end of 1990s; groundwater was overextracted by 90 billion cubic meters in the Haihe River plain by 2002 and the subsidence area was around 20,000 square kilometers; biodiversity is decreasing and the intrusion of exotic species threatens ecological safety, causing major economic loss. Trends in Regional and Basin-based Hybrid Pollution China’s environmental issues are significantly different when compared with those that were discussed two decades ago. In fact, the issues are in “transition.” This is evidenced by the expansion of pollu­ tion from land to offshore areas and from surface water to ground­ water, and the overlaying of point pollution and nonpoint pollution, and distinction between domestic and industrial sewage. The pollut­ ant composition includes both toxic...