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1.
中国作为世界上最大的发展中国家,正经历着越发严重的农业污染问题;对农业污染防控的制度性约束因素进行深入分析,是实现有效污染防控的前提,具有积极的理论和现实意义。对中国农业污染防控的制度约束分析研究表明:农业污染及其防控涉及的利益主体关系及相关制度设计,对各利益主体形成了污染防控负激励,加重了农业污染;城乡"二元"结构及其衍生的一系列体制问题,导致"三农"在农业环境治理、农村公共物品提供等方面被严重边缘化,进而直接制约了农业污染防控;此外,高度分散的小规模农户经营模式也不利于农业污染防控。最后,针对中国农业污染防控的制度性约束因素,提出了有针对性的农业污染防控政策建议。  相似文献   

2.
This paper reports the use of LIDAR technique, vertical wind profiler (VWP) and the coupled MM5-CMAQ air quality modeling system to investigate a high PM10 concentration episode occurred in Beijing, China during January 8–9, 2004. Through the regression analysis between the observed PM10 concentrations and the observed extinction coefficients, the converting formulas from the LIDAR records to the PM10 mass concentrations in Beijing have been found. Further, a 2-level-nested grid domain with spatial resolutions of 36 and 12 km have been designed and employed for this study, and the coupled MM5-CMAQ modeling system has then been evaluated using both the ground-level PM10 observations and the vertical profiles of PM10 deduced from the measured LIDAR extinction coefficients. Based on the verified modeling system, two emission scenarios were designed to quantitatively assess the trans-boundary PM10 contributions from the surrounding provinces of Beijing. The results illustrated that the particulate matter buildup over the Beijing region was due to a number of factors, including pollutants brought in from its surrounding provinces by the southwest winds and the emission from local sources within Beijing. It indicates that while Beijing needs to take positive steps to reduce its own pollution emissions, much effort should also be placed on demanding more pollution reduction and better environmental performance from its surrounding provinces.  相似文献   

3.
中美城市土壤污染控制与管理体系的比较研究   总被引:11,自引:0,他引:11       下载免费PDF全文
赵沁娜  杨凯  徐启新 《土壤》2006,38(1):6-10
城市土壤污染对城市生态环境的可持续性以及人体健康带来了相当大的风险,其控制与管理已经成为我国环境管理中的一个新问题。本文对中美两国城市土壤污染控制与管理体系进行了比较研究,认为我国现有城市土壤污染控制与管理体系滞后于城市大气、水环境污染控制与管理,没有形成专门的土壤污染防治法规体系,土壤环境影响评价尚无推荐的行业导则,缺乏土壤污染评估标准,土壤污染状况信息不透明,公众和社区参与意识不强烈以及如何准确地识别污染土壤的程度和数量、判定污染者所承担的责任、筹措土壤污染处置基金等问题都是土壤污染控制与管理过程中的薄弱环节等。另外,从管理机构、政策法规、技术工作手段以及经济责任的认定等方面提出了改进措施。  相似文献   

4.
5.
Water, Air, & Soil Pollution -  相似文献   

6.
The acute effects of air pollution on human health and the environment are well understood and the arguments for measures to prevent local, gross pollution are strong. Governments and the public will accept the need for controls where effects are obvious. At the broader scale where effects may be more subtle, and where the costs of abatement are high, a convincing case is necessary before acceptable solutions are adopted. An education process is needed to provide the relevant facts in an understandable form. For major air pollutants, where international agreement for control of emissions is required, effect-based instruments have proved successful in Europe. These are designed to be cost effective by offering protection to the more sensitive areas by targeting the cheapest emission controls on the sources responsible for effects. This level of complexity has demanded improved education and communication for all those involved in the decision-making process. The principles and approaches that have provided success are discussed. Attention to these is needed in the future if more stringent and costlier measures are to be agreed.  相似文献   

7.
农业污染国内外研究进展及防控对策建议   总被引:1,自引:0,他引:1  
农业污染具有原因复杂、影响滞后、发生随机、途径广泛等特征,已成为农产品质量下降以及食品源头污染的主要影响因素,国外发达国家在农业污染研究与控制方面已经积累了很多经验。通过对我国农业污染现状分析,依据我国农业污染研究成果和技术发展水平,借鉴国外经验,提出了有针对性的农业污染防控对策建议。  相似文献   

8.
通过野外调查取样与实验测定相结合的方法,对兰州市农业生态系统土壤-蔬菜体系49个样点进行研究,分析探讨了研究区蔬菜与土壤的铅污染水平以及蔬菜铅富集效应特性。结果表明:①蔬菜种植地土壤铅平均含量为26.30 mg.kg-1,合格率为93.62%,在不同县区存在显著差异,其大小顺序为红古区〉榆中县〉永登县;②蔬菜铅平均含量为0.59 mg.kg-1,合格率为60.78%,在不同县区存在显著差异,其大小顺序为永登县〉榆中县〉红古区;③蔬菜铅富集系数为(1.69±2.99)%,永登县蔬菜的铅富集能力显著高于榆中县和红古区,不同种类蔬菜铅富集能力在不同县区具有差异性;④土壤全钾除与白菜和甘蓝有正相关性以外,与其他蔬菜均为负相关性,其中与白菜、番茄、土豆显著相关,与胡萝卜为极显著相关;⑤土壤速效钾与各种蔬菜的铅富集能力均为正相关性,其中与胡萝卜、甜菜、甘蓝为显著正相关,与番茄、土豆、菜花为极显著正相关;⑥土壤pH值与胡萝卜、甜菜铅富集系数呈显著负相关,与菜花呈极显著负相关。研究表明,兰州市不同蔬菜产区的各类蔬菜对土壤铅的富集具有明显的差异性,同时不同形态的钾元素及土壤pH值对蔬菜铅富集能力具有显著的影响。  相似文献   

9.
Chongqing City in China has suffered from serious air pollution and acid rain caused by low graded raw coal (sulfur=ca. 3≈5%, ash=ca. 30%) combustion. In this paper, the situation of atmospheric pollution and acid rain in Chongqing are discussed, the reduction efficiency for sulfur dioxide (SO2) with the bio-briquetting of the raw coal that is one of countermeasures for emission control of air pollutants due to domestic consumes was determined. The research indicated that the frequency of acid rain was high, more than 50% at urban area, and its pH was low, about 4.5. Under our experimental conditions, the reducing efficiency of sulfur SO2 emission from high sulfur coal-biomass briquette amounted to 87%. The field investigation indicated that SO2 indoor concentrations in case of using bio-briquette dropped to 1/2≈1/3 of the raw coal.  相似文献   

10.
A number of positive changes have taken place since Estonia regained its independence in 1991. Air pollution from stationary sources has decreased over 2.5 times during 1990–1999, emissions of solid particles and SO2 have declined 74% and 60%, respectively. The content of heavy metals in Estonian mosses has decreased in comparison with the early 1990s. Last five years occurrence of different kind of damages on decidious trees has not been frequent. Those facts indicate that air pollution with heavy metals and other pollutants has diminished during the last few years. As the pH of precipitation fluctuates in different parts of Estonia, it is very important to study the effect of precipitation on ecosystems on the basis of critical loads. Results indicate that, as for eutrophicating nitrogen, the actual nitrogen deposition in North-East Estonia and West-Estonian islands roughly coincides with the limits for pollution endurance. This pattern also applies to the total deposition of sulphur and nitrogen in South, North and North-East Estonia, although in some Northern and North-Eastern areas pollution endurance limits have been exceeded.  相似文献   

11.
Typical mid-winter anthropogenic air pollution episodes are caused when pollutants are trapped in the lower atmospheric boundary layer due to the generation of surface inversion favored by synoptic conditions. We analyzed the optical properties of atmospheric aerosol particles obtained during one such episode using a sun/sky radiometer at two measurement sites: one located in the densely populated and industrialized central part of Israel, and the other in a reference site, about 150 km away. Aerosol optical thickness and volume size distributions showed an increased burden of fine aerosol particles in the central part of Israel. In order to verify the local origin and anthropogenic nature of the effect, the analysis was accompanied by examinations of the synoptic conditions, air mass backward trajectories, and conventional in situ air pollution measurements made by a ground-based sampling station. This case study shows the ability of optical measurements to track urban and industrial atmospheric air pollution expressed by high concentration of fine aerosol particles. In addition, it emphasizes the role of local Israeli air pollution sources and may explain the difference in the properties of long-term aerosol optical observations between the two sites. The advantages of the optical method presented are speed (almost instantaneous), automated measurement, and sensitivity to aerosol particle concentration as well as aerosol size fraction. The drawback is that the optical measurements discussed deal only with aerosol particles and cannot distinguish between different types of pollutant gases.  相似文献   

12.
流域农业非点源污染的控制对策研究   总被引:3,自引:0,他引:3  
农业非点源污染是一种分布广泛的非点源污染类型,以下河套小流域为例,从宏观管理的角度出发,提出了控制农业非点源污染的对策及建议,包括强调流域生态系统的整体功能,加强流域范围内的水,大气,土壤和其它生态资源的综合管理,根据流域生态环境的特点,包括受污染和破坏和程度,编制流域保护规划;实现以生态工程为核心的流域生态环境建设。  相似文献   

13.
以不同种植区生长的1~3年生兰州百合为供试材料,采用生长分析方法对不同生长时期地下鳞茎的营养物质进行检测,记录种植区气温变化数据。结果显示,10月9日永靖关山乡、渭源田家河乡、临洮玉井镇3个种植区1~3年生兰州百合鳞茎粗淀粉含量相比较,差异均达极显著水平(P < 1%)。粗淀粉含量从高到低均为临洮玉井镇、永靖关山乡、渭源田家河乡。不同种植区的气温对1~3 年生兰州百合生长后期鳞茎粗淀粉含量影响不同。3年生兰州百合生长后期,渭源田家河乡百合鳞茎粗淀粉含量与平均最高气温、平均最低气温和平均温差显著正相关;临洮玉井镇百合鳞茎粗淀粉含量与平均最高气温极显著负相关,与平均温差显著负相关。其余种植区与各气温因子相关性不显著。不同种植区的兰州百合生长后期鳞茎膨大生长速度和粗淀粉累积不同,品质差异明显。  相似文献   

14.
Water, Air, &; Soil Pollution -  相似文献   

15.
高超  陈财  罗纲 《水土保持学报》2021,35(3):359-368
基于1961—2019年淮河流域140个气象站点的日尺度降水数据和2000—2016年的月尺度的地表温度(LST)、归一化植被指数(NDVI)数据,利用表征气象干旱的标准化降水指数(SPI)挑选确定冬小麦不同生长期的典型干旱年份;利用表征农业干旱温度植被干旱指数(TVDI),借助Landsat-8数据提取淮河流域冬小麦...  相似文献   

16.
Bull  K.R.  Achermann  B.  Bashkin  V.  Chrast  R.  Fenech  G.  Forsius  M.  Gregor  H.-D.  Guardans  R.  Haubmann  T.  Hayes  F.  Hettelingh  J.-P.  Johannessen  T.  Krzyzanowski  M.  Kucera  V.  Kvaeven  B.  Lorenz  M.  Lundin  L.  Mills  G.  Posch  M.  Skjelkvåle  B. L.  Ulstein  M. J. 《Water, air, and soil pollution》2001,130(1-4):119-130
For 20 years the Convention on Long-range Transboundary Air Pollution has worked to control air pollutant emissions in Europe and North America. Its Working Group on Effects (WGE) has been responsible for much of the underpinning science. The WGE's six International Cooperative Programmes (ICPs) on Waters, Natural Vegetation and Crops, Forests, Materials and Cultural Heritage, Integrated Monitoring, and Modelling and Mapping, together with a Joint Task Force on Human Health with WHO, quantify air pollution effects on the environment through monitoring, modelling and scientific review. Early work found evidence to support the need for decreases in emissions of sulphur and nitrogen pollutants. More recently, monitoring results and models have provided the scientific basis, e.g. critical loads and levels, for effects-based Protocols and for evaluating their effectiveness. ICP studies on trends show recovery from acidification effects in keeping with the fall in sulphur emissions. Steady-state models provide an indication of long-term improvements. Recent increased emphasis on developing dynamic models will enable better links between recovery rates and abatement strategies. The scientific network of the ICPs and the monitoring and modelling results have been key to the development of the Convention and are an essential component for its success in the future.  相似文献   

17.
我国集约化农业中氮污染问题及防治对策   总被引:8,自引:0,他引:8  
概述了我国部分地区因过量施用化肥氮而导致对地面水、地下水及蔬菜造成硝酸盐污染的现状 ;提出了制定《农田施肥污染防治管理规定》等防止农业生态环境氮污染的对策意见  相似文献   

18.
南方塑料大棚冬春季温湿度的神经网络模拟   总被引:8,自引:0,他引:8  
利用浙江省慈溪市草莓塑料大棚和南京信息工程大学农业气象试验站番茄塑料大棚的小气候观测数据及气象站资料,建立3个以棚外辐射、温度、相对湿度和风速为输入变量,棚内温度和相对湿度为输出变量的BP神经网络预测模型。结果表明,3个模型气温训练值与实测值的均方根误差(RMSE)都在2℃以内,相对误差都在4%左右;相对湿度训练值的RMSE都在7个百分点以内,相对误差不超过7%。利用此模型得到的气温预测值与实测值的RMSE都在2℃左右,冬季气温的相对误差较大,春季通风和不通风模型气温的相对误差不超过6%;相对湿度预测值的RMSE都在7个百分点以内,相对误差不超过9%。说明所建BP神经网络模型对于不同季节、不同通风条件、不同作物的大棚温湿度模拟都有较高的精度,能够满足棚内温湿度的预测要求,且对温度的模拟精度高于对相对湿度的模拟。  相似文献   

19.
中国农田土壤重金属污染防治挑战与对策   总被引:48,自引:5,他引:48  
我国农田土壤重金属污染格局多样,区域污染风险突出。发达国家对污染土壤的修复经验对我国具有借鉴意义。我国农田土壤重金属污染防治面临土壤重金属空间异质性强、土壤类型及农作物品种对重金属累积差异大、土壤酸化严重、土壤元素失衡、不科学的发展方式、土壤重金属累积趋势难以逆转、土壤—农作物重金属累积线性关系不显著,修复技术不完善、修复措施长期风险调控机制缺失等主要挑战。根据我国农田土壤污染防治现状及课题组工作基础,我们提出以预防为主、保护优先和风险管控为基本思路,建立土壤污染防治体系,通过"土壤环境质量调查、土壤污染源头管控、分类管理和土壤环境质量基准推导"等4个步骤推进农田土壤重金属污染防治工作。  相似文献   

20.
水体硝态氮污染是水污染研究的焦点之一。通过对兰州市7个县区农村98个生活饮用水水样的测定分析,结合国家相关标准(GB5749—2006),对兰州市农村生活饮用水硝态氮含量进行评价,并通过回归分析推断了不同水源类型水体硝酸根与电导率的相关性。结果显示:①兰州农村生活饮用水水体硝态氮平均含量为(5.42±6.63)mg·L-1,合格率为86.73%;②皋兰县、西固区和安宁区农村生活饮用水硝态氮含量无超标现象,榆中县、七里河区、永登县、红古区农村生活饮用水硝态氮含量较高,有不同程度超标现象,合格率分别为77.27%、77.78%、80.00%和83.33%;③不同水源类型水体硝态氮含量存在显著差异:自来水、河水和水库水合格率均为100%;窖水、深井水(〉30m)和泉水硝态氮含量较高,合格率分别为92.00%、91.66%和55.56%;浅井水(〈30m)硝态氮平均含量最高,为(22.27±10.54)mg·L-1,合格率仅为25.00%;④除水库水和浅井水,其他类型水体硝酸根与电导率呈显著或极显著的正相关性;⑤浅井水中水体硝态氮含量与pH呈显著负相关;⑥浅井水和泉水水体硝态氮含量与农田氮投入量存在显著正相关性。  相似文献   

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