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1.
当前滇池水污染的治理措施主要关注农业面源污染和城市生活污水,忽视了城市化过程中不透水表面带来的城市面源污染问题。采用基于遥感、GIS的生态环境影响评估模型,分析了滇池流域不透水表面的水环境效应。结果表明:不透水表面面积增加可导致流域地表径流量增加以及水质下降,进而导致流域水环境问题日益严重;当子流域不透水表面覆盖率(ISC)控制在0%~8%时,流域水环境状况良好;当ISC增长到8%~23%时,流域水环境受到影响;超过23%时,将形成不可逆转的水体污染,流域水环境严重退化。根据滇池17个子流域的不透水表面覆盖率大小,提出了滇池流域的子流域分类规划与治理思路,详细列出了分类治理的具体措施。  相似文献   

2.
流域综合水管理是发达国家普遍采用的管理模式,主要手段之一是制定流域水环境保护总体规划.流域水环境保护总体规划是流域各相关利益方就流域社会经济发展与水环境保护达成的决策,是其他所有规划制定的基础和依据,核心内容是规划目标的确定.流域水环境保护总体规划是流域综合管理的决策平台和信息共享平台,是环境保护的刚性约束,为流域水资源开发利用划定红线.流域水环境保护总体规划是目标导向型的,通过指标体系指导省级行政区负责制定的小流域水环境保护规划,协调流域内省级行政区国民经济和社会发展规划、土地利用总体规划、城市总体规划等其他部门规划.中国目前缺乏流域水环境保护总体规划,基于此提出了国家级流域水环境保护总体规划的一般模式,包括基本内容、规划文本和规划实施3个部分.流域水环境保护总体规划实施的主要手段是审批小流域水环境保护规划.  相似文献   

3.
按照重要性、迫切性、可行性等原则制订了15项连云港市海洋生态环境建设优先项目,内容涵盖了污染治理渔业资源的保护及恢复、生态环境保护能力建设等领域,优先项目投资的生态效益显著。  相似文献   

4.
中国流域水环境保护规划体系设计   总被引:1,自引:0,他引:1  
现行与流域水环境保护相关的规划很多,但是由于各地区、各部门协调不足,规划间没有明确的关系,缺乏接口和控制,规划内容不统一,致使流域水环境保护规划没有形成体系。基于流域水环境保护相关规划存在的问题和当前的政府管理体制,提出了由国家流域水环境保护总体规划、小流域水环境保护规划、城市水环境保护规划和大点源水污染物减排规划构成的流域水环境保护规划体系。明确了该体系内,上级规划通过审批和评估实现对下级规划的指导与控制,规划之间的衔接关系体现为指标的联结。同时,提出了制定流域水环境保护规划法规、制定规划编制规范和指南、建立信息共享平台等建议。  相似文献   

5.
杭州西湖水生高等植物的恢复与水生生态修复   总被引:4,自引:3,他引:4  
在过去的50年,西湖一直被富营养化问题所困扰。迄今为止,采用了各种工程措施进行治理,耗资数亿,但收效不明显。为了进一步解决西湖富营养化问题,提出需要用生态方法去解决生态问题,通过生态学手段,恢复、重建高等水生植物带落,增加水生生物多样性,改善西湖水生生态系统的结构和功能,控制藻类来修复西湖水生生态系统。科学地选择先锋种类组合、消除草食性鱼类的影响、合理地控制水位是西湖水生植被恢复过程中的三个重要措施。  相似文献   

6.
淮河流域水生态环境现状评价与分析   总被引:7,自引:0,他引:7  
为了全面评价淮河闸坝与污染对淮河水生态的影响,必须首先对水生态现状有一个全局的认识。从淮河流域全局出发,通过对淮河典型河段的水生态和水环境进行现场调查与室内分析,对流域内水生态环境现状进行了综合评价。采用生物学指数与水生物指示环境结合的方法评价水体污染程度、生态系统稳定性与河流/水库的健康程度。评价结果表明:(1)颍河中下游地区与沭河中下游地区水生态系统脆弱,河流多处于病态;(2)涡河付桥闸、东孙营闸到蒙城闸段水生态系统不稳定,河流不健康,但下游河段水生态有自恢复迹象;(3)洪汝河河流多处于亚健康状态,水生态环境自修复能力较强;(4)淮干水生态环境质量的突变点在临淮岗,上游较好;(5)西部、南部山区水库水生态环境质量最好;(6)整个流域水生态质量西高东低,南高北低;优劣顺序为:西部、南部山区>洪汝河水系>涡河中下游地区>颍河、沭河中下游地区。建议枯水期加大淮干以南及上游山区水库的下泻流量,保持河道畅通和一定流速,提高水体自净能力,同时控制颍河、涡河上游污染物的排放,联合调度水量与水质,淮河水生态得以修复。  相似文献   

7.
重庆市重污染次级河流伏牛溪水污染控制与水质改善   总被引:1,自引:0,他引:1  
雷沛  王超  张洪  周健 《环境工程学报》2019,13(1):95-108
针对重庆市部分次级河流耗氧污染物负荷高、水动力学弱化、河流生态系统退化等问题,选取重庆市典型次级河流伏牛溪为研究对象,以水质目标管理为指导思想,开展重污染河流水污染控制与水质改善研究。以V类水为水质目标,通过划分治理单元,开展河流水环境容量核算,分别提出基于现状条件、规划用地及上游补水2种情景下的污染负荷削减计算;根据削减负荷分配的结果,提出各个治理单元的污染负荷削减目标与治理措施,并开展目标可达性分析。治理工程实施后,重庆市伏牛溪水体中主要污染物的平均浓度及年达标率满足考核要求,该方案为我国山地城市重污染河流的水环境治理提供很好的参考。  相似文献   

8.
根据东太糊形成的历史和演变情况,分析了该湖泊功能的变化。近十年来,该湖生态环境出现了一些令人担忧的情况,主要是水产养殖面积成倍增长,水生生物大幅度减少,水环境质量明显下降,湖泊淤积日趋严重。为了保护东太湖生态环境,恢复湖泊自然生态平衡,作者从生态的保护、水资源的合理利用、污染治理的工程和管理措施等方面探讨了东太湖水污染控制的途径。  相似文献   

9.
针对淮河流域河南段部分河流出现的水资源过度开发利用、水质恶化和生物多样性下降等生态退化问题,根据淮河流域河南段主要河流退化特点,以改善淮河流域河南段退化现状为目标,在河流生态修复技术研究和工程实践的基础上,按照修复技术的功能,筛选出水量调整、水质净化和生物多样性提高等3类共13种适合淮河流域河南段河流生态系统修复技术。为使流域水生态修复更具针对性,根据流域内主要河流断流频率和洪/枯比计算,将流域内的河流分为常年有水型和间歇性断流型,然后以修复模式为修复范式研究的基本单元,分别针对流域内常年有水型河流生态系统的退化特点构建了3种修复模式,针对流域内间歇性断流型河流生态系统的退化特点构建了5种修复模式,以期为流域内退化河流生态系统的修复提供指导。  相似文献   

10.
流域水环境模型是水环境保护和流域管理工作的重要支撑工具。总结了国外流域水环境模型管理体系、技术支撑方法、标准化建设实践和法规化应用的实际经验,通过梳理中国流域水环境模型的发展历程和应用现状,对比分析了影响中国流域水环境模型标准化和法规化的主要障碍和问题,提出了中国流域水环境模型法规化建设的发展建议。  相似文献   

11.
Staples CA  Gulledge W 《Chemosphere》2006,65(4):691-698
Ethylene oxide (EO) is mainly used as a chemical intermediate and as a fumigant and sterilizing agent. Through its manufacturing and intended uses, EO may be released into the environment. Therefore, an assessment of the environmental significance of those potential emissions was conducted. Data were collected describing pertinent physical properties, degradation and other loss mechanisms that control the fate of EO in the environment. Available aquatic and terrestrial ecotoxicity data were assembled and used as the basis of calculating critical toxicity values to characterize hazard. Environmental compartment concentrations of EO were calculated using Level III fugacity-based modeling. Six scenarios were developed to account for different climatic conditions in various portions of the US. Finally, potential regional-scale risks to aquatic and terrestrial wildlife were determined. In the conceptual model that was developed in this assessment, EO diffuses into air, partitions between environmental compartments, is transported out of the different compartments via advection, and undergoes abiotic and biological degradation within each compartment. All known emissions within the continental USA were assumed to enter a modeled region roughly the size of the State of Ohio. Organisms (receptors) were assumed to dwell in both terrestrial and aquatic compartments. Receptors were assumed to include small mammals, soil invertebrates, water column (pelagic) organisms, and sediment benthos. The goal of this assessment was to characterize any potential adverse risks to terrestrial and aquatic wildlife populations. Hazard Quotients (HQ) were calculated by dividing predicted concentrations of EO in air, water, sediment, and soil by their critical toxicity values. Maximum calculated HQ values in air were 1.52x10(-7), in water were 1.17x10(-5), in sediment were 2.25x10(-4), and in soil were 1.37x10(-5). The results of this assessment suggest that EO as currently manufactured and used does not pose adverse risks to aquatic or terrestrial wildlife. In all cases, the HQ values were much less than the maximum desired HQ value of 1.0 (4,400-6,600,000 times), indicating that the potential for diffuse emissions of EO to pose adverse environmental risks is quite low.  相似文献   

12.
生态农业的发展,是经济、社会和环境保护协调发展的产物。作者提出生态农业的给排水循环系统作为现有模式的延伸和补充,让生态农业在经济、社会、环境的协调发展中发挥更大的作用,最大限度地消除农业污染,为农业可持续发展提供技术支持和可靠保证。  相似文献   

13.
华北山区位于华北平原与陕甘黄土高原以及内蒙古高原之间,是我国经济欠发达地区之一。它又是我国华北平原、京津唐等大城市工农业和生活用水的主要源地,生态环境类型复杂多样,但由于人类活动频繁,自然植被破坏严重,生态系统结构紊乱,功能脆弱,自身恢复能力较弱。积极开展华北山区的环境综合整治与生态建设不仅对解决当地人民的生活和生存问题具有重要的意义,而且对于我国华北地区经济的发展也具有重要的战略意义。本文详细分析了华北山区的生态系统特点和存在的问题,并在此基础上提出在该区环境综合整治与生态建设的具体措施和途径。  相似文献   

14.
The fate, effects, and potential environmental risks of ethylene glycol (EG) in the environment were examined. EG undergoes rapid biodegradation in aerobic and anaerobic environments (approximately 100% removal of EG within 24 h to 28 days). In air, EG reacts with photo-chemically produced hydroxyl radicals with a resulting atmospheric half-life of 2 days. Acute toxicity values (LC(50)s and EC(50)s) were generally >10,000 mg/l for fish and aquatic invertebrates. The data collectively show that EG is not persistent in air, surface water, soil, or groundwater, is practically non-toxic to aquatic organisms, and does not bioaccumulate in aquatic organisms. Potential long-term, quasi-steady state regional concentrations of EG estimated with a multi-media model for air, water, soil, and sediment were all less than predicted no effect concentrations (PNECs).  相似文献   

15.
Propylene glycol ethers (PGEs) are comprised of mono-, di- and tri-PGEs and several of their acetate esters. The nature of the range of applications that use PGEs suggests that there is a potential for both intentional and unintentional entry of the materials into the environment. Selected physical/chemical properties, fate characteristics, aquatic toxicity data and calculated environmental concentrations were used to assess potential risks from the manufacture, handling, use, and disposal of PGEs. In general, the PGEs are low to moderately volatile, have high aqueous solubilities, low octanol-water partition coefficients (Kow), and bioconcentration factor values of <10, which indicate they are unlikely to accumulate in aquatic food chains. Both abiotic and biological degradation processes reduce environmental concentrations of PGEs. In air, vapor-phase PGEs react with photo-chemically produced hydroxyl radicals and have half-lives ranging from 5.5 to 34.4 h. A variety of ready and inherent biodegradation test methods, as well as tests that simulate biodegradation in wastewater treatment plants, surface water and soil have been conducted on PGEs. Significant aerobic biodegradation was generally observed, with a range of biodegradation half-lives on the order of 5-25 d. Acute aquatic toxicity studies with PGEs resulted in LC50 values ranging from approximately >100 to >20,000 mg/l for freshwater fish, the pelagic invertebrate Daphnia magna, green algae Selenastrum capricornutum (now called Pseudokirchneriella capricornutum) and bacteria. Level 3 multi-media modeling (EQC model of Mackay) was used to simulate regional-scale concentrations of PGEs in air, soil, water, and sediment. Toxicity thresholds were then compared with regional-scale water, soil and sediment concentrations to determine hazard quotients. Based upon this analysis, concentrations of PGEs are unlikely to pose adverse risks to the environment.  相似文献   

16.
在作者多年研究工作和查阅大量文献资料的基础上,本文综述了环境数学模型国内外的研究现状、发展历史及未来趋势。重点介绍了这方面研究的最新进展。该文还介绍了本领域所涉及的理论和实际应用问题,提出了今后值得进行研究的若干前沿课题,给出了60余篇关于水环境数学模型研究的主要参考文献目录。  相似文献   

17.
The objectives of this work were estimate the reaction rates of hydrolysis of carbosulfan to carbofuran and subsequent degradation of this last compound in irrigated rice fields, and the respective half life, in aquatic environment and soil solution, by mean of numerical solution of differential ordinary linear equations system that describes the kinetics of insecticide concentrations. The results indicated that the carbosulfan and carbofuran have low persistence in water and medium persistence in soil solution of tropical irrigated rice fields. However, both compounds can be found in laminar water and soil solution in concentration above environmental and human safety limits.  相似文献   

18.
Ecotoxicity evaluation of selected sulfonamides   总被引:6,自引:0,他引:6  
Sulfonamides (SAs) are a group of antibiotic drugs widely used in veterinary medicine. The contamination of the environment by these pharmaceuticals has raised concern in recent years. However, knowledge of their (eco)toxicity is still very basic and is restricted to just a few of these substances. Even though their toxicological analysis has been thoroughly performed and ecotoxicological data are available in the literature, a systematic analysis of their ecotoxicological potential has yet to be carried out. To fill this gap, 12 different SAs were chosen for detailed analysis with the focus on different bacteria as well as non-target organisms (algae and plants). A flexible (eco)toxicological test battery was used, including enzymes (acetylcholinesterase and glutathione reductase), luminescent marine bacteria (Vibrio fischeri), soil bacteria (Arthrobacter globiformis), limnic unicellular green algae (Scenedesmus vacuolatus) and duckweed (Lemna minor), in order to take into account both the aquatic and terrestrial compartments of the environment, as well as different trophic levels. It was found that SAs are not only toxic towards green algae (EC50 = 1.54-32.25 mg L−1) but have even stronger adverse effect on duckweed (EC50 = 0.02-4.89 mg L−1) than atrazine - herbicide (EC50 = 2.59 mg L−1).  相似文献   

19.
Electron capture or negative ion chemical ionisation gas chromatography-mass spectrometry was employed to measure concentrations of short and medium chain length polychlorinated n-alkanes extracted from samples of water, river sediment, benthos, fish, soil, digested sewage and earthworms. Analysis of samples from 20 aquatic and eight agricultural sites indicated that short and medium chain length polychlorinated alkanes were present in the following concentration ranges: sediment < 0.2-65.1 mg/kg dry weight, water < 0.1-1.7 micrograms/l, fish < 0.1-5.2 mg/kg wet weight, benthos < 0.05-0.8 mg/kg wet weight, digested sewage 1.8-93.1 mg/kg dry weight, soil < 0.1 mg/kg dry weight, and earthworms < 0.1-1.7 mg/kg wet weight. It is clear from this study that these compounds are widely distributed in the UK environment, although it is not yet possible to fully assess the risks posed to either wildlife or humans by their continued use. Further study of these compounds is indicated.  相似文献   

20.
The chemical and ecotoxicological characteristics of fresh and stabilized industrial organic sludge leachates were compared to obtain information regarding how the stabilization process can influence the ecotoxic potential of this industrial waste, which could be used for the amendment of degraded soil. Physicochemical analysis of the sludge leachates, as well as a battery of eco(geno)toxicity tests on bacteria, algae, daphnids, and higher plants (including Vicia faba genotoxicity test) and the determination of hydrolytic enzyme activity, was performed according to standard methods. The chemical comparison of the two types of leachate showed that the samples obtained from stabilized sludge had a lower organic content and higher metal content than leachates of the fresh sludge. The eco(geno)toxicological results obtained with aquatic organisms showed that the stabilized sludge leachate was more toxic than the fresh sludge leachate, both originating from the same industrial organic sludge sample. Nevertheless, phytotoxicity tests carried out with a reference peat soil irrigated with stabilized sludge leachate showed the same toxicity as the fresh sludge leachate. In the case of the industrial solid organic sludge studied, stabilization through a biodegradation process promoted a higher metal mobility/bioavailability/eco(geno)toxicity in the stabilized sludge leachate compared to the fresh sludge leachate.  相似文献   

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