Heavy metal content in oysters (Crassostrea gigas) cultured in the Ebro Delta in Catalonia, Spain

The aim of this study was to determine heavy metal content (As, Cd, Cu, Hg, Cd, Pb, and Zn) in oysters transplanted in Ebro Delta bays (Alfacs and Fangar) where oysters are traditionally cultured for human consumption. Metal body burdens were monitored weekly during the period of maximal agriculture activity from May to June in 2008 and 2009. Results indicate that regardless of the high levels of metals reported in biota living in Ebro River, metal levels in oysters from both bays were similar to those found in unpolluted areas and far below the maximum limits of tolerance recommended by the European Commission. Nevertheless, metal accumulation patterns in oysters differentiate two sources of pollution: one coming from agriculture activities within the Ebro’s delta for As, Cd, Cu, and Zn and other coming from Ebro River probably related to industrial activities upstream (Hg, Pb) or to lead shot pellets form hunting activities (Pb). Reported results, thus, are in concern with previous studies and indicate that metallic pollutants do not affect oysters cultures in Ebro Delta associated bays.     

Effectiveness of wastewater management in rural areas of developing countries: a case of Al-Chouf Caza in Lebanon

Ghaggar, one of the major rivers of northern India originating in outer Himalayas and flowing through the state of Punjab, Haryana, and Rajasthan, is put to multiple uses. Along its course of 464 km, it receives discharge from various cities and runoff from agricultural lands. Punjab and Haryana are two predominantly agricultural states of India using substantial amounts of agrochemicals, yet there are no reports available in literature on the level of pesticides in the stretch of river Ghaggar through Punjab and Haryana. This is the first report on pesticide pollution of the river Ghaggar in Haryana. Water samples along the 230-km stretch of the river in Haryana were analyzed for the presence of organochlorine insecticide residues. While aldrin and dieldrin were below detection limits, both hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) were traceable in all the water samples. High concentration of β-HCH among ΣHCH indicates old pollution source whereas predominance of p,p^′ -DDT among ΣDDT reflects its recent use in the catchment area of the river. The concentrations of HCH and DDT in all the samples were above the permissible limits prescribed by the European Commission Directive for drinking purposes.     

Water Quality Assessment of Osun River: Studies on Inorganic Nutrients

The present investigation provides data of some ions, namely Na⁺, Ca²⁺, NH₄ ⁺,Cl^-, NO₃ ^-,CN^- and PO₄ ^3- on water samples of river Osun,selected rivers in the region and groundwaters. The pH,temperature, electrical conductivity (EC), total dissolvedsolids (TDS), total hardness (TH) and total carbon (IV) oxide(TCO₂) have also been determined to asses the chemicalstatus and pollution levels of these water sources. The highervalues of certain parameters with respect to the acceptablestandard limits for drinking water indicate the pollution inboth groundwater and river water samples of the study area, and make the waters unsuitable for various applications. Thehigh pollution river water source showed higher levels ofphosphate, nitrate and ammonium ions (P < 0.05). There is nosignificant difference (P < 0.05) between the meanconcentrations of other inorganic nutrients in the high and lowpollution water source types. The correlation coefficientbetween quality parameter pairs of river water and groundwatersamples are determined and the significance of these parametersin both types of water sources are discussed.     

长江三角洲地区低层大气污染物O3、NOx、SO2的数值模拟

通过对比分析发现,2007年客观源清单比2001年初始源清单能够更好地反映当前长江三角洲地区的大气污染物源排放情况.基于客观源清单,利用第三代空气质量模式(Models-3/CMAQ)较好地模拟出长三角地区近地层大气浓度的日变化和空间分布,模拟结果表明,NOx与O3在空间分布上并不一致,两者之间存在非线性关系,NO2与...     

Impact evaluation of agrotechnologies in watersheds

The special project RAISA (Advanced Researches for Innovation in Agricultural Systems) of the National Research Council of Italy concerns the development of new methodologies for the study and evaluation of the impact of agrotechnologies on the environment. In the project, several trans-disciplinary Units have worked together since 1990. The aim of the project is to define systems, using tools such as remote sensing and Geographical Information Systems, for decision making support in land planning and land use management, with particular attention to groudwater table pollution. The fundamental steps for evaluation of the impact of agrotechnologies on the Po river watershed, 75,000 km² in northern Italy, and Tevere (Tiber) river watershed, 17.169 km² in Central Italy are described here. The study concerns particular areas located in the western part of the Po River plain, where flooded rice is the main crop, and in the central plain of the Tevere basin where the risk of water pollution is considerable, due to small and medium sized swine breeding farms. The aspects considered were water pollution due to mineral nitrogen used to fertilize the rice crop and the nitrogen contained in the waste water from pig farms. For the Po river basin the methodology developed was based on the integration of satellite remote sensing images, and the available cartography, such as topographic and thematic maps, together with the hydrological and the toxicological data of the chemical fertilizers employed, summarized in maps of the groundwater table pollution hazard. A simpler evaluation was obtained in the Tevere river basin: the thematic layers were crossed in bi-directional matrices and the result merged with the map of the territorial distributionof the swine. In both cases the selected information was integrated and processed in Integrated sub-basin scale. The GISs led to the development of a user-friendly system for formalizing our knowledge of the degree of pollution hazard in simple and readable maps.Research supported by National Research Council of Italy, Special Project RAISA, sub-project N. 1 Paper N.     

A study of the heavy metal concentrations of the Singapore River

The concentrations of lead, cadmium, copper, zinc, iron, and mercury in the water, sediment and biota of the Singapore River were determined. The concentration of the various metals in water showed significant variation at different sampling times and there was enrichment of lead content. The spatial patterns of metal distribution in the sediment could be due to the different pollution sources such as exhaust emission from boats and other environmental variables such as clay content of sediment or tide level. In the biota, higher amounts of metals were found in species inhabiting the river bed while organisms of higher trophic level such as free-swimming fishes and crabs accumulated lower amounts. In general, the flesh of fishes and crabs had the least content of metals compared to other tissues. The Concentration of various metals in bivalve, Mytilopsis sallei, which were found extensively in the river did not reflect the pollution distribution.     

The Netherlands' environmental policy for the North Sea and Wadden Sea

The water quality management of The Netherlands' part of the North Sea (57 000 km² continental shelf of which 7600 km² is territorial sea to 12 miles) and the Wadden Sea (a wetland area behind the northern coastal islands), is described on the basis of recent scientific studies and governmental policy documents. The links with international conventions and treaties are mentioned. The overall water quality in these areas has significantly deteriorated over the last century, notably since the post-war industrial revival, due to a great number of emissions of heavy metals and organochlorine substances. A dramatic decline of seals and porpoises has occurred. However, over the last few years some emissions have been reduced. A national ecological research programme for the North Sea is developing. Monitoring is concentrated on levels of pollutants as well as on effects upon biota. Baseline standards are now being developed as references for further action against pollution. If the recent trend towards improvement is to continue, it requires that the increased economic activities (notably the mining of oil and gas, petrochemical production, and incineration and dumping of chemical wastes) be kept sufficiently under control. A need is felt for a continued rational harmonization and planning of all activities on the North Sea. An even more stringent planning is required for the Wadden Sea which is now an international nature reserve under the Wetland Convention and is eligible for designation as a Biosphere Reserve under the UNESCO-MAB-programme. The river Rhine as greatest polluter of the North Sea and Wadden Sea urgently needs a clean-up.     

Irrigation Efficiency and Quality of Irrigation Return Flows in the Ebro River Basin: An Overview

The review analysis of twenty two irrigation efficiency (IE) studies carried out in the Ebro River Basin shows that IE is low (average IE)_avg(= 53%) in surface-irrigated areas with high-permeable and shallow soils inadequate for this irrigation system, high (IE)_avg(= 79%) in surface-irrigated areas with appropriate soils for this system, and very high (IE)_avg(= 94%) in modern, automated and well managed sprinkler-irrigated areas. The unitary salt (total dissolved solids) and nitrate loads exported in the irrigation return flows (IRF) of seven districts vary, depending on soil salinity and on irrigation and N fertilization management, between 3–16 Mg salt/ha⋅ year and 23–195 kg NO)₃ ⁻-N/ha⋅ year, respectively. The lower nitrate loads exported from high IE districts show that a proper irrigation design and management is a key factor to reduce off-site nitrogen pollution. Although high IE’s also reduce off-site salt pollution, the presence of salts in the soil or subsoil may induce relatively high salt loads (≥14 Mg/ha⋅ year) even in high IE districts. Two important constrains identified in our revision were the short duration of most surveys and the lack of standards for conducting irrigation efficiency and mass balance studies at the irrigation district level. These limitations {emphasize the need for the establishment of a permanent and standardized network of drainage monitoring stations for the appropriate off-site pollution diagnosis and control of irrigated agriculture.     

Human health risk assessment of environmental and dietary exposure to natural radionuclides in the Catalan stretch of the Ebro River, Spain

This study was aimed at assessing the levels of ²¹⁰Pb and ²¹⁰Po concentrations as well as gross alpha and beta activities in environmental monitors from the Catalan stretch of the Ebro River (Spain), potentially influenced by the presence of sediments with high concentrations of ²³⁸U and its decay chain daughters in the Flix reservoir. The chronic daily intake of ²¹⁰Pb and ²¹⁰Po through ingestion and inhalation of soils was evaluated, and the derived non-carcinogenic and carcinogenic risks were characterized. The low concentration of radioisotopes in soils resulted in a negligible annual effective dose. The levels of ²¹⁰Pb and ²¹⁰Po were determined in various groups of highly consumed food (fish and seafood, vegetables, fruits, and rice), and their dietary intake was calculated. The annual effective dose for the adult people from food intake was estimated in 3.3 × 10^???2 mSv, mostly due to ²¹⁰Po. Overall, the current radioactivity levels in the Catalan stretch of the Ebro River should not mean any additional health risk for the population living nearby. However, an integral assessment of the risks derived from exposure to other pollutants (e.g., metals and organochlorine compounds) jointly with radionuclides could be of great interest.     

Spatial and seasonal distribution of 17 endocrine disruptor compounds in an urban estuary (Mondego River,Portugal): evaluation of the estrogenic load of the area

The Mondego River estuary demonstrates signs of pollution, but the levels of endocrine disrupting compounds (EDCs), such as the natural (17β-estradiol and estrone) and pharmaceutical (17α-ethynylestradiol) estrogens, xenoestrogenic industrial pollutants (4-octylphenol, 4-nonylphenol, and their mono- and diethoxylates and bisphenol A), phytoestrogens (formononetin, biochanin A, daidzein, and genistein), and sitosterol were either poorly or never measured in this area. Thus, to conclude about the influx of EDCs in this estuary, water samples were taken every 2 months, during 1 year (2010) in low tide, at eight sites distributed along the estuary. Water samples (1 L) were preconcentrated in the Oasis HLB cartridges and cleaned in silica cartridges before their analysis by GC-MS. In summer, potentially hazardous amounts of estrogens (≈26 ng L^?1), alkylphenols (≈11.5 μg L^?1), alkylphenolethoxylates (≈13 μg L^?1), and phytoestrogens (≈5.6 μg L^?1) were measured. These data suggest that changes in the hydrodynamics of the estuary coupled with the increase of water temperatures interfere with the amount of EDCs in the water. Complementary physicochemical parameters also point to high levels of anthropogenic pollution in this area. Globally, the estrogenic load, expressed in ethynylestradiol equivalents, attained 71.8 ng L^?1 demonstrating that, all together, the measured EDCs pose important health risks for both biota and humans.     

黄河流域甘肃段面源污染估算与空间分析

采用遥感分布式面源污染评估模型（DPeRS）,对2018年黄河流域(甘肃段)面源污染空间分布特征进行分析,具体包括多类型污染量产排特征解析和流域优先管控单元识别。结果表明,污染量上,2018年黄河流域（甘肃段）总氮(TN)、总磷(TP)、氨氮(NH₃^-N)、化学需氧量(COD_Cr)的面源污染排放负荷分别为65.6,11.8,19.1和77.2 kg/km²,入河量分别为836.7,33.3,220.2和1 353.3 t;空间分布上,氮型(TN和NH₃^-N)排放负荷高值区主要分布在流域中部和东部局部地区,流域大部分地区TP排放负荷均较高,COD_Cr面源污染排放负荷高值区分布较为零散。与排放负荷相比,黄河流域（甘肃段）面源污染入河负荷并不突出,这与该地区水资源量少有密切关系。筛选出黄河流域（甘肃段）面源污染优先控制单元15个,面积占比为85.2%,I类优控单元主要分布在庆阳市、天水市、兰州市和白银市等地区,II类优控单元主要分布在甘南藏族自治州,且TN、TP、NH₃^-N和COD_Cr面源污染优控单元识别结果的平均精度达到80%。     

Ecological principles of World Ocean monitoring

Anthropogenic effect on the World Ocean in the course of exploiting its resources has led to a significant contamination of some ocean areas in the latest decades and to diminution of the natural capacity of marine ecosystems to reproduction and self-regulation. Thus, the most urgent problem of today has become evident: the problem of the World Ocean pollution and its negative ecological effects. Local pollutions and their ecological effects on the World Ocean go on acquiring large-scale regional and even global character since the elements of ocean ecosystems and the ocean properties are interrelated and interconditioned. Looking into pollutant transfer and transformation in the marine environment we can distinguish four subsystems: ocean-land, ocean-atmosphere, and water-bottom sediments interfaces as well as ocean water mass. Ocean-atmosphere and water-floor subsystems require special consideration since their coefficients of pollutant accumulation are much greater than that of the water mass. Besides water exchange, the processes of pollutant transfer in the water mass effect the interference between the solute and suspended matter on the one hand, and water mass-biota interaction on the other. Atmospheric transport and deposition of chemical toxicants are considerable sources of the World Ocean pollution; their share in the total balance of the anthropogenic pollution influx into marine environment is commensurable with the river runoff. The most dangerous, among various pollutants entering the World Ocean, are oil, hydrocarbon chlorides (pesticides, polychloride bifenyls), toxic metals (mercury, cadmium, lead), i.e. globally occurring chemical compounds continuously entering the marine environment and effecting marine organisms and their populations. Still new and new pollutants are being discovered now in the oceans: chloride and polychloride terpenes, nitrosamines, chlordane, etc. The problems of eutrophication and microbiological contamination of the inland seas and ocean coastal zones are becoming still more urgent. Accumulation of aromatic polycyclic carcinogenous hydrocarbons. BaP in particular, is pregnant with unexpected ecological effects. The highest PAH concentrations have been observed in the sea coast areas and in the zones of intensive navigation. Rather high coefficients (10²–10⁴) of BaP accumulation in the sea biota and bottom sediments are marked. Ecological and biological effects of changes in the chemical composition of the ocean make up the chain of interrelated reactions; transformation of natural biogeocenoses, disturbance of the cycle of carbon, nitrogen, sulphur and other elements, reduction of biological productivity and cell genome affection present the most essential effects of these reactions. Stresses in the abiotic component of the ecosystem are expressed through disturbances in the chemical balance, changes in the evaporation from the sea surface, oil aggregate formation (floatable biocenoses), disturbances in reducing reactions of biogenous elements, salinity and temperature variation, and so on. Population-biocenotic effects of the man-made impact, actually important for the level of ecosystem stability, include the following processes of the structural and functional character:

1. alteration of the mean biomass of plankton and benthos populations, in particular in semi-enclosed seas and off-shore ocean areas;
2. alteration of the number of higher taxons-genera or families of the sea organisms, in particular replacement of the dominant populations of mass species, and emergence of hydrobionts new for the marine environment;
3. alteration of the relations between the numbers of some taxonomic groups of hydrobionts and abundant development of indicator species of the sea biota, e.g. BaP and PCB oxidizing microorganisms;
4. disturbances in production/destruction processes of organic substances;
5. energy flux changes in the marine ecosystem.

Analysis of the current knowledge on the ocean environment pollution and its negative effects has enabled to formulate the main directions of the World Ocean ecological monitoring. Investigations of the biogeochemical cycles of pollutants and elements in the marine environment, identification of the effect of pollutants abundant in the ocean on the Earth's climate and hydrochemical regime as well as major geophysical processes in the ocean and atmosphere make up integral parts of the ocean monitoring together with the studies of pollutant impact on the ocean biota which leads to biological regime alterations and affection of the sea organisms genofond.     

Anthropogenic nexus on organochlorine pesticide pollution: a case study with Tamiraparani river basin,South India

The levels of 17 organochlorine pesticides residues (OCPs) in surface water and sediments from Tamiraparani river basin, South India were investigated to evaluate their potential pollution and risk impacts. A total of 96 surface water and sediment samples at 12 sampling stations were collected along the river in four seasons during 2008–2009. The ΣOCP concentrations in surface water and sediments were in the range of 0.1 to 79.9 ng l⁻¹ and 0.12 to 3,938.7 ng g⁻¹ dry weight (dw), respectively. Among the OCPs, the levels of dichlorodiphenyltrichloroethanes (DDTs), aldrin, dieldrin, cis-chlordane, trans-chlordane, and mirex were dominant in the sediments. The dominant OCPs in water samples are heptachlor, o,p′-DDE, dieldrin, o,p′-DDD, and mirex, which show different source of contamination pattern among sampling seasons. The distribution pattern of DDTs, hexachlorocyclohexane, and other OCPs in the present study shows heterogenic nature of nonpoint source of pollution. Notable contamination of water and sediment sample that was observed in upstream (S2) 58 ng l⁻¹ and downstream (S11) 1,693 ng g⁻¹ dw explains agricultural and municipal outfalls, whereas frequent damming effect reduces the concentration level in the midstream. The overall spatial–temporal distribution pattern of ΣOCP residues are illustrated by GIS package.     

浑太河流域水质达标控制方法研究

结合浑太河流域水资源网络节点图,根据污染物来源、种类及其产生机理,针对计算单元水资源供需平衡预测数据、降雨径流值,分点源、非点源进行规划水平年污染物入河量的预测。根据浑太河流域地形特征、入河污染物降解特性,以水功能区水体纳污能力为计算单元污染物排放总量控制条件,给出基于规划水平年入河污染物变动特性的水质达标控制方法。运用该方法进行浑太河流域水质达标控制:2030年,流域总需水7.4亿立方米,缺水深度在1%以下,COD、NH3-N、TP、TN的入河量分别为28.5×104、2.8×104、3.1×104、4.6×104t,对应的入河控制量分别为9.3×104、0.6×104、0.8×104、0.9×104t,经控制后水功能区目标水质达标率100%。证实了该水质达标控制方法有效、可行。     

Assessment of multiple anthropogenic contaminants and their potential genotoxicity in the aquatic environment of Plitvice Lakes National Park,Croatia

In this study, the influence of anthropogenic pollution on the aquatic environment of Plitvice Lakes National Park (PLNP) was investigated during 2011–2012 using a combination of chemical and cytogenetic analyses. Four groups of major contaminants [(volatile organic compounds: benzene, toluene, ethylbenzene, and xylenes (BTEX); persistent organochlorine pollutants: organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs); major and trace elements; anthropogenic radionuclides (⁹⁰Sr, ¹³⁴Cs, and ¹³⁷Cs)] were determined in three aquatic compartments (water, sediment, fish). Mass fractions of inorganic constituents in different compartments reflected the geological background of the area, indicating their origin from predominantly natural sources. Levels of volatile and persistent organic compounds in water and fish, respectively, were very low, at levels typical for remote pristine areas. Analysis of anthropogenic radionuclides in water and sediment revealed elevated activity concentrations of ¹³⁷Cs in water, and measurable ¹³⁴Cs in the upper sediment layers from April 2011, possibly as a consequence of the Fukushima nuclear accident in March 2011. The potential genotoxicity of river and lake water and lake sediment was assessed under laboratory conditions using the alkaline comet assay on human peripheral blood lymphocytes, and measured levels of primary DNA damage were within acceptable boundaries. The results showed that despite the protected status of the park, anthropogenic impact exists in both its terrestrial and aquatic components. Although contaminant levels were low, further monitoring is recommended to make sure that they will not rise and cause potentially hazardous anthropogenic impacts.     

Risk Assessment of Organic Pesticides Pollution in Surface Water of Hangzhou

Advances in research on pollution of organic pesticides (OPs) in surface water, pollution survey and risk assessments of organochlorine pesticides (OCPs) and organophosphorus pesticides (OPPs) of surface water in Hangzhou are conducted. Total concentrations of dichloro-diphenyl-trichloroethane (DDT) and hexachloride-benzene (HCH) in surface water were observed to be 0–0.270 μg/L and 0–0.00625 μg/L respectively. DDE, as a metabolite of DDT and many species of OPP_S were determined in some samples of surface water. Parathion, the main pollutant among OPPs in surface water of Hangzhou, was observed to be 0–0.445 μg/L. Based on these experimental results, health risk assessments on the organic pollution are developed. It is observed that the total risk “R ^T” at present time of surface water in Hangzhou is mainly contributed by organophosphorus pesticides, especially Parathion; HCH and DDT are not the main contaminants; on the contrary, organophosphorous pesticides, especially Parathion, must be of concern at the present time.     

南通平原河网地区典型农田系统地下水硝态氮污染调查

针对平原河网地区典型农田系统灌溉施肥带来的地下水环境污染问题,采集南通地区蔬菜地、水稻-小麦轮作地、水稻-油菜轮作地和桑地地下水样品,分析了不同农田种植体系下的地下水污染程度。结果表明,蔬菜、桑地、水稻-油菜轮作、水稻-小麦轮作地地下水的硝态氮(N)平均值分别为12.2,9.53,7.95和6.12 mg/L,与氮肥用量呈显著的正相关关系;研究区域地下水硝态氮超Ⅲ类标准率(20 mg/L)的为4.8%,表明地下水已部分受到硝态氮污染。     

Atmospheric depositional fluxes and sources apportionment of organochlorine pesticides in the Pearl River Delta region, South China

Organochlorine pesticides (OCPs) have variously been phased out in agricultural activities, but they are still widely detected in air, water, and soil systems due to their recalcitrant nature in the environment. The purposes of this study were to assess potential OCP pollution via dry and wet deposition over the fast developing Pearl River Delta area with 41,700 km², where the main effort has been focused on emerging pollutants such as petroleum hydrocarbons and PM2.5. We quantified both the dry and wet deposition fluxes of 19 OCPs including dichlorodiphenyltrichloroethanes (DDTs), endosulfans (Endos), and hexachlorocyclohexanes (HCHs). The results showed that each year about 67.4, 42.0, 15.0, and 8.07 kg of total OCPs, DDTs, Endos, and HCHs were returned to the ground, among which 11.7, 10.4, 0.84, and 0.16 kg were in the dry deposition forms. The large spatial variations in OCP deposition fluxes indicated that OCP pollution in the air is mainly influenced on local scales because evaporation from local soil is likely the major source of the phased out OCPs. Source analysis indicated that DDTs may be still in use as antifouling agent and/or dicofol, but Endos and HCHs were mainly derived from the residual of historical usage. The study suggests that the historical OCP pollutants are persistent at high levels in this area and should not be overlooked, while we tackle emerging pollutants.     

Using Satellite and Other Data to Estimate the Annual Water Demand of an Irrigation District

Locating and forecasting water needs can assist the location of water in dry regions, and improve the management of reservoirs and the canal network. Satellite, ground data, and agrometeorological data were combined to forecast the volume of irrigation water needed during 1993 and 1994 in an irrigation district of 327 km2 located in the Ebro basin, Spain. The main crops were rice, alfalfa plus forage, winter cereals (barley and wheat), sunflower and maize. Their extent was estimated every year by frame area sampling and a regression estimator with satellite data. Initial crop area statistics were obtained by expansion of the sample areas to the entire study area and then a regression estimator with the multitemporal supervised classification of two Landsat-5 TM images was applied. This procedure improved the precision of the estimates by expansion. Net water requiremets (m3 ha-1) of the above mentioned crops were computed from reference evapotranspiration estimates, crop coefficients and effective precipitation. These computations were performed for an average year, i.e. by using long-term averaged meteorological data. Crop hectarage and net crop water requirements were multiplied to obtain, for the entire study area, the volume (hm3 106 m3) of the net crop water requirements. After subtraction of water taken directly from the rivers and non-productive sunflower, the irrigation water volumes were estimated. The comparison of these forecasts with the volumes of water invoiced by the Ebro Basin Water Authority confirmed the feasibility of forecasting the volume of water applied to an individual irrigation district. This is an objective and practical method for estimating the irrigation water volume applied in an irrigated area.