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1.
明确了建设用地土壤污染状况调查监管的对象,分析了我国现阶段调查监管存在的监管力量不足、从业门槛不明确、实时监管措施缺乏等问题。结合国内外调查工作监管经验和近年苏州工业园区调查监管的探索实践,提出了鼓励引导相关利益方参与调查监管、建立健全从业人员和机构监管制度、引入监理机制、推进信息化过程管理等对策建议。  相似文献   
2.
The High Plains aquifer (HPA) is the primary water source for agricultural irrigation in the US Great Plains. The water levels in many locations of the aquifer have declined steadily over the past several decades because the rate of water withdrawals exceeds recharge, which has been a serious concern to the water resources management in the region. We evaluated temporal trends and variations in agricultural water use and hydroclimatic variables including precipitation, air temperature, reference evapotranspiration, runoff, groundwater level, and terrestrial water storage across the HPA region for different periods from 1985 to 2020 at the grid, county, or region scale. The results showed that water withdrawals decreased from 21.3 km3/year in 1985 to 18.2 km3/year in 2015, while irrigated croplands increased from 71,928 km2 in 1985 to 78,464 km2 in 2015 in the entire HPA. The hydroclimatic time-series showed wetting trends in most of the northern HPA, but drying and warming trends in the southern region from 1985 to 2020. The groundwater level time-series indicated flat trends in the north, but significant declining in the central and southern HPA. Trends in irrigation water withdrawals and irrigation area across the HPA were controlled by the advancement of irrigation systems and technologies and the management of sustainable water use, but also were affected by dynamical changes in the hydroclimatic conditions.  相似文献   
3.
Fish may bioaccumulate contaminants from the aquatic environment and extend them to the food chain provoking risks to human health. This study evaluated the microbiological parameters of the pond´s water and trace elements concentrations in samples of water, sediment, feed and muscle of farmed Nile tilapia used for human consumption in southern Brazil. A total of 240 fish were collected from 12 tilapia farms. Sediment, tank water and dry ration used in the animals' diet were collected for analysis. Analysis were performed by Energy Dispersion X-ray Fluorescence (EDXRF), Inductively Coupled Plasma Mass Spectrometer (ICP-MS), Induced Coupled Plasma Optical Emission Spectrometer (ICP-OES), and Atomic Absorption Spectrometer (AAS-VGA). In addition, the microbiological analysis of the water was carried out. The concentrations of Se, I, Fe, Cu and Zn in fish muscle were higher than the recommended by the Brazilian legislation, considering the advised daily intake for adults. The arsenic element had concentrations above the limit stipulated by the present Brazilian legislation, observed in all samples of muscle, sediment and tank water highlighting a possible environmental and fish contamination by the toxic element. Moreover, the arsenic concentration in the water presented a positive correlation (ρ?=?0.33) with arsenic in the muscle, suggesting that tilapia is a good environmental bioindicator, once they properly reflect the levels of arsenic in the water. It is suggested to perform an arsenic speciation for quantification of the inorganic form and accurate assessment of the degree of toxicity in the muscle samples and risks it can bring to human health. Regarding the other potentially toxic elements (Hg, Pb and Cd), and microbiological analysis of water it was verified that the consumption of the fish in question does not raise risks, since the values are within a quality benchmark established by law. The concentration of total and fecal coliforms in pond´s water in the facilities was in agreement with the microbiological indexes required by the legislation of CONAMA class II. Western region presented the lowest concentrations of fecal coliforms when compared to the other regions. There was no significant difference in the microbiological counts of total heterotrophic bacteria, Vibrio spp. and Pseudomonas spp. among the regions.  相似文献   
4.
全(多)氟烷基化合物(per(poly)fluoroalkyl substances,PFASs)在环境各个介质及人体样品中广泛被检出,近年,在室内空气和灰尘中也普遍发现PFASs.研究表明,室内空气中PFASs的含量普遍高于室外空气,室内空气和灰尘中的PFASs可能是室外空气的污染来源及人体暴露源,因此室内环境中PFASs成为环境领域的又一个研究热点.但目前为止,我国还没有开展室内空气中PFASs的相关研究,室内灰尘中PFASs的研究也相对较少.本文就室内空气和灰尘中PFASs的采样与分析方法、污染现状、来源分析及人体暴露等4个方面进行了综合阐述,以期为我国室内环境中PFASs的研究提供参考.  相似文献   
5.
地下水砷污染是全球化环境问题.本文基于阿克苏地区平原区2017年75个地下水砷实测含量进行分析.结果表明,研究区地下水砷含量变化范围为ND—98.70μg·L-1,平均值为9.42μg·L-1,超标率达26.7%.水平方向上,高砷地下水主要集中在研究区的中部偏南一带;垂直方向上,山麓斜坡冲洪积砾质平原潜水区地下水砷含量平均值表现为深层潜水>浅层潜水,中下游河流冲积平原区承压水区地下水砷含量平均值表现为深层承压水>浅层承压水>潜水.采用绘制Piper三线图、Gibbs图、离子比例图等方法对研究区地下水砷的富集因素进行研究.结果表明,研究区地下水砷主要为自然来源;封闭的地质构造和造山带与河流等沉积环境相结合的水文地质条件有利于研究区地下水砷的富集;研究区高砷地下水水化学类型主要为HCO3·SO4-Na,还原性-弱碱性环境利于地下水砷富集;研究区地下水砷受强烈的蒸发浓缩作用进一步浓缩,同时地下水阴离子浓度增大加剧了地下水中阴离子与砷酸根、亚砷酸根之间的竞争吸附,利于地下水砷的富集.  相似文献   
6.
通过调研对国内外文丘里洗涤过滤型FCVS性能评价进展进行了阐述与比较,指出国内开展文丘里洗涤过滤型FCVS出厂性能评价不全面,需进一步开展相关性能评价技术研究;FCVS在现场的安装质量如何,随着时间的推移性能变化如何,并未开展试验验证,结合法规要求等,建议开展FCVS现场试验评价技术的研究。  相似文献   
7.
现阶段,工业的生产任务越来越繁重,因此在其进行生产的时候,制造的污染物也会越来越多。在这个对于环保极度关注的时代,本文对于被污染的土壤还有地下水实施修复展开讨论。  相似文献   
8.
Water quality index (WQI) models are generally used in hydrochemical studies to simplify complex data into single values to reflect the overall quality. In this study, deep groundwater quality in the Chittur and Palakkad Taluks of the Bharathapuzha river basin of Kerala, India, was assessed by employing the WQI method developed by the Canadian Council of Ministers of the Environment (CCME). The assessment of overall water quality is indispensable due to the specific characteristics of the study area, such as geography, climate, over-drafting, and prevalent agricultural practices. Forty representative samples were collected from the study area for monsoon (MON) and pre-monsoon (PRM) seasons. The results showed a general increase of contents from MON to PRM. The major cations were spread in the order Ca2+>Na+>Mg2+>K+ and the anions HCO3>Cl>CO32− based on their relative abundance. Among various parameters analysed, alkalinity and bicarbonate levels during MON were comparatively high, which is indicative of carbonate weathering, and 90% of the samples failed to meet the World Health Organization (WHO, 2017)/Bureau of Indian Standards (BIS, 2012) drinking water guidelines. The CCME WQI analysis revealed that nearly 50% of the samples during each season represented good and excellent categories. The samples in the poor category comprised 10% in MON and 15% in PRM. The overall WQI exhibited 15% of poor category samples as well. The spatial depiction of CCME WQI classes helped to expose zones of degraded quality in the centre to eastward parts. The spatial and temporal variations of CCME WQI classes and different physicochemical attributes indicated the influence of common factors attributing to the deep groundwater quality. The study also revealed inland salinity at Kolluparamba and Peruvamba stations, where agricultural activities were rampant with poor surface water irrigation.  相似文献   
9.
基于DRASTIC的丽水市地下水防污性能评价   总被引:5,自引:1,他引:4  
地下水防污性能反映地下水系统遭受污染的可能性,可以为土地利用规划、地下水资源保护规划、地下水水质监测等提供科学依据。此论文结合丽水市的水文地质条件,对DRASTIC评价模型进行了改善,建立了符合丽水市的DRAMTIC评价模型。该模型由大气降雨入渗补给量、地下水埋深、包气带介质、水力传导系数、含水层厚度、地下水开采强度、地形坡度等7个因子组成,以乡镇单元等为界线划分不规则评价单元,评分体系由单因子区域分布规律确定,采用主成分—因子分析法分析各因子的权重体系;利用差分法对各因子加权叠加的综合指数进行等级划分,应用GIS技术得到丽水市地下水防污性能评价图。该模型的评价结果客观科学,能有效的为规划部门及地下水资源管理部门服务。  相似文献   
10.
四川红层浅层风化带裂隙水水化学特征的聚类分析   总被引:1,自引:0,他引:1  
四川红层盆地浅层风化带裂隙水是区内分布最为广泛和目前开采最多的浅层地下水类型,本文通过对大量控制性水样分析结果进行聚类分析,探讨了该地区浅层风化带裂隙水的水化学成分特征及其分布规律,结果表明区内91%以上的浅层风化带裂隙水为HCO3-型淡水,主要分布在中部方山丘陵小区、南部台状低山丘陵小区和东部侵蚀构造平行岭谷低山丘陵小区。该研究可为开发利用浅层地下水提供地学依据。  相似文献   
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