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1.
四种不同方法在土壤重金属污染评价中的应用比较   总被引:8,自引:0,他引:8  
Four assessment methods (two pollution indexes and two fuzzy mathematical models) were employed to investigate the environmental quality of four soils around a ferroalloy plant in Nanjing City. Environmental quality was assessed as class Ⅳ (moderately polluted) for each soil with single-factor index method, and was identified to be classes Ⅳ, Ⅲ (slightly polluted), Ⅲ, and Ⅲ for soils A, B, C, and D, respectively, with the comprehensive index model. In comparison with the single-factor index method, the comprehensive index model concerned both dominant parameter and average contribution of all factors to the integrated environmental quality. Using the two fuzzy mathematical methods (single-factor deciding and weighted average models), the environmental risks were determined to be classes Ⅳ, Ⅲ, Ⅱ (clean), and Ⅱ for soils A, B, C, and D, respectively. However, divergence of the membership degree to each pollution class still occurred between the two methods. In fuzzy mathematical methods, membership functions were used to describe the limits between different pollution degrees, and different weights were allocated for the factors according to pollution contribution. Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of environmental risk assessment.  相似文献   

2.
一种基于模糊的修复后土壤环境风险综合评价方法   总被引:3,自引:0,他引:3  
Environmental risks pertaining to contaminated soils have been well studied, while little attention has been paid to the risks of the soils after remediation. In this study, a concept model developed based on fuzzy set theory was applied to evaluate the uncertainties of three risk indicators, namely, plant growth, groundwater safety and human health, of a restored site that had been previously polluted by heavy metals. The concept model classified the grade and importance of risk factors by an 11-level ranking system and was able to yield a comprehensive risk result rather than multi-risk results for complex risk indicators. Modeling results showed that the risks to the three indicators were effectively reduced after the remediation. Moreover, great sensitivity of the risks was found related to the weight distribution among the three risk indicators. In general, the risks of both polluted and restored soils to the environment were in the order of groundwater safety 〉 plant growth 〉 human health. The model was proved to solve the problems of multi-risk results due to complex risk indicators that previously encountered by other researchers, which made it helpful in decision-making and management of restored soils.  相似文献   

3.
猪舍环境适宜性模糊综合评价   总被引:6,自引:3,他引:3  
猪舍环境是影响猪健康水平、生长和繁殖的重要因素,对养猪生产起着决定性作用,受到广泛的关注。然而,猪舍环境是由多个环境因子相互耦合而形成的复杂的非线性时变系统。对各环境因素适宜性的描述并不是一个确定的数值,而是在一定范围内的模糊概念。目前,针对猪舍环境优劣评价大多仅限于单一环境因素,缺少基于多个环境因素的猪舍环境适宜性综合评价研究。因此,该文构建了评价指标体系和权重,根据猪舍养殖环境标准建立各环境因子的隶属度函数,提出了基于模糊集理论的猪舍多环境因子适宜性综合评价方法。以美国普渡大学 SERB 猪舍环境监测的24组数据为例对该文提出的方法进行了验证,结果表明,该文建立的猪舍环境适宜性模糊综合评价方法比单一环境因素的评价更加全面,能科学合理地反映出猪舍环境质量状况,可以很好地为猪舍环境调控提供数据参考。  相似文献   

4.
The Health Council of the Netherlands organised an international workshop on the fate of pesticides in the atmosphere and possible approaches for their regulatory environmental risk assessment. Approximately forty experts discussed what is currently known about the atmospheric fate of pesticides and major gaps in our understanding were identified. They favoured a tiered approach for assessing the environmental risks of atmospheric dispersion of these chemicals. In the first tier a pesticide's potential for emission during application, as well as its volatilisation potential should be assessed. Estimates of the former should be based on the application method and the formulation, estimates of the latter on a compound's solubility in water, saturated vapour pressure and octanol/water partition coefficient. Where a pesticide's potential for becoming airborne exceeds critical values, it should be subjected to a more rigorous second tier evaluation which considers its toxicity to organisms in non-target areas. This evaluation can be achieved by calculating and comparing a predicted environmental concentration (PEC) and a predicted no-effect concentration (PNEC). By applying an extra uncertainty factor the PNEC can be provisionally derived from standard toxicity data that is already required for the registration of pesticides. Depending on the distance between the source and the reception area, the PEC can be estimated for remote areas using simple dispersion, trajectory type models and for nearby areas using common dispersion models and standard scenarios of pesticide use. A pesticide's atmospheric transport potential is based on factors such as its reaction rate with OH radicals. It should be used to discriminate between those compounds for which only the risks to nearby ecosystems have to be assessed, and those for which the risks to remote ecosystems also have to be determined. The participants were of the opinion that this approach is, in principle, scientifically feasible, although the remaining uncertainties are substantial. Further field and laboratory research is necessary to gain more reliable estimates of the physico-chemical properties of pesticides, to validate and improve environmental fate models and to validate the applicability of standard toxicity data. This will increase both the accuracy of and our confidence in the outcome of the risk assessment.  相似文献   

5.
Background, aim, and scope  Ecotoxicological risk assessment of sediments is usually based on a multitude of data obtained from tests with different endpoints. In the present study, a fuzzy logic-based model was developed in order to reduce the complexity of these data sets and to classify sediments on the basis of results from a battery of in vitro biotests. Materials and methods  The membership functions were adapted to fit the specific sensitivity and variability of each biotest. For this end, data sets were categorized into three toxicity levels using the box plot and empirical methods. The variability of each biotest was determined to calculate the range of the gradual membership. In addition, the biotests selected were ranked according to the biological organisation level in order to consider the ecological relevance of the endpoints measured by selected over- or underestimation of the toxicity levels. In the next step of the fuzzy logic model, a rule-base was implemented using if...and...then decisions to arrive at a system of five quality classes. Results  The results of the classification of sediments from the Rhine and Danube Rivers showed the highest correlation between the biotest results and the fuzzy logic alternative based on the empirical method (i.e. the classification of the data sets into toxicity levels). Discussion  Many different classification systems based on biological test systems are depending on respective data sets; therefore, they are difficult to compare with other locations. Furthermore, they don‘t consider the inherent variability of biotests and the ecological relevance of these test systems as well. In order to create a comprehensive risk assessment for sediments, mathematical models should be used which take uncertainties of biotest systems into account, since they are of particular importance for a reliable assessment. In the present investigation, the variability and ecological relevance of biotests were incorporated into a classification system based on fuzzy logic. Furthermore, since data from different sites and investigations were used to create membership functions of the fuzzy logic, this classification system has the potential to be independent of locations. Conclusions  In conclusion, the present fuzzy logic classification model provides an opportunity to integrate expert knowledge as well as acute and mechanism-specific effects for the classification of sediments for an ecotoxicological risk assessment. Recommendations and perspectives  In order to achieve a more comprehensive classification, further investigation is needed to incorporate results of chemical analyses and in situ parameters. Furthermore, more discussions are necessary with respect to the relative weight attributed to different ecological and chemical parameters in order to obtain a more precise assessment of sediments.  相似文献   

6.
As a waste-derived soil amendment with a long history, biochar has received extensive attention for its capability to improve soil fertility/health; remove or immobilize contaminants in soil, water and air; and mitigate climate change. With the aim of producing engineered biochars with excellent performances, new trends in biochar pyrolytic production and modification strategies have emerged. This review critically summarizes novel pyrolysis methods (e.g., microwave-assisted pyrolysis, co-pyrolysis and wet pyrolysis) and modification approaches (e.g., mineral modification, photocatalytic modification, electrochemical modification) with a focus on (a) the mechanisms involved in environmental remediation processes including soil immobilization, contaminant adsorption and catalytic oxidation; (b) effects of feedstock and pyrolysis conditions on physicochemical properties; (c) sustainability considerations in novel modification and pyrolysis strategies; and (d) the feasibility of extrapolating the results from wastewater treatment to soil remediation. It is argued that in order to achieve the maximum net environmental benefits, ‘greener’ modification methods are warranted, and the risks associated with pyrolysis of contaminated feedstock in soil amendment and contaminant sorption can be minimized through various novel approaches (e.g., co-pyrolysis). Furthermore, novel pyrolysis methods can be combined with emerging modification strategies to synthesize more ‘effective’ biochars. Considering the similar aims of modification (e.g., increase surface area, introduce oxygen-containing functional groups, increase aromaticity), the applicability of several novel approaches could in future can be expanded from contaminant adsorption/degradation in aqueous media to soil remediation/fertility improvement.  相似文献   

7.
工业遗留场地复合型污染分层健康风险评估研究   总被引:2,自引:0,他引:2  
许伟  施维林  沈桢  张建荣  郑家传 《土壤》2016,48(2):322-330
以某典型有机物-重金属复合型污染场地为研究对象,根据该场地水文地质特征将土层划分为回填土(0~4.1 m)、粉质黏土(4.1~6.5 m)、粉土(6.5~8.5 m)和粉砂(8.5~13.8 m)等4层,运用HERA软件分别进行健康风险评估,推算了土壤和地下水的风险值及修复目标值,并以此划分修复范围和确定修复技术。结果表明,土壤中存在严重的有机污染(苯和甲苯)和重金属(Cr(Ⅵ))污染,苯的最大致癌风险为0.000 155,甲苯的最大非致癌危害商为2.14;Cr(Ⅵ)在下层土壤中不存在暴露途径危害人体健康,而仅在表层回填土中存在致癌和非致癌危害商(0.014 2和97.6);地下水中关注污染物健康风险在可接受范围内;苯、甲苯在各土层中的修复目标值分别为:回填土层0.434、708 mg/kg;粉质黏土层0.807、2 460 mg/kg;粉土层1.42、4 440 mg/kg;粉砂层2.51、8 140 mg/kg;Cr(Ⅵ)仅在回填土层计算出修复目标值为0.251 mg/kg。苯、甲苯等挥发性有机物分层修复目标值随土层深度增加而变大,Cr(Ⅵ)等重金属修复目标值不遵循这个规律,因此,分层健康风险评估更适用于挥发性有机物健康风险评价。  相似文献   

8.
针对目前土地利用规划环境影响评价系统的不确定性,在理解集对分析(SPA)原理的基础上,利用原创联系度的可展性对其进行改进,将其扩展到四级评判,并结合信息熵法,以山西省晋城市为例,建立了基于改进SPA法的土地利用规划环境影响评价模型,并利用该模型在构建以水环境、土壤环境、大气环境与生态环境为子系统的区域自然环境质量评价指标体系的基础上,对晋城市土地利用规划影响自然环境质量的10项指标进行了综合评价。此外,为了验证改进SPA法对土地利用规划环境影响评价的合理性与可行性,将其评价结果与模糊综合评价结果以及多指标综合评价结果进行了比较。结果表明:自第3轮土地利用规划执行以来,晋城市从2007年的自然环境质量Ⅱ级到2009年的Ⅲ级,2011年的Ⅱ级,2013年的Ⅰ级,总体上晋城市自然环境质量呈现出由Ⅲ级向Ⅰ级转化的正向发展趋势;改进SPA法综合评价结果与模糊综合评价结果以及多指标综合评价结果基本一致。研究认为利用改进的集对势进行土地利用规划环境影响跟踪评价具有一定的可行性,评价结果较接近实际情况,为土地利用规划环境影响跟踪评价提供了一种科学合理且简单实用的评价方法。  相似文献   

9.
土地利用变化直接影响生态过程,不同土地利用类型对区域生态风险的影响存在差异。采用三峡库区2007、2010年两期遥感数据、社会数据、经济数据以及环境监测数据,基于PSR模型构建评价指标体系,利用综合模糊评价法建立评价模型,对三峡库区屏障带重庆段土地利用生态风险进行评价。结果表明:三峡库区屏障带重庆段土地利用生态风险总体以中度风险为主,2007—2010年有恶化的趋势,其中长寿、奉节、江津、巫溪、云阳的风险等级在升高;仅有石柱以及巫山两个评价单元的生态风险等级降低。三峡库区屏障带重庆段土地利用生态风险空间由东北向西南逐渐降低。2007—2010年,高风险与较高风险区域扩大,低风险区域消失。研究结果可为三峡库区生态保护提供参考。  相似文献   

10.
南方典型设施蔬菜生产系统镉和汞累积的健康风险   总被引:3,自引:0,他引:3  
胡文友  黄标  陈永  董騄睿 《土壤学报》2014,51(5):1045-1055
选取南京市典型设施蔬菜生产系统为研究对象,研究了设施土壤-蔬菜系统中镉和汞的累积特征,评价了不同类型蔬菜中镉和汞的暴露风险,提出了基于健康风险的设施菜地土壤镉和汞的环境质量基准。结果表明:(1)设施菜地表层土壤中镉和汞产生了明显累积,且土壤汞的平均含量超过了温室蔬菜产地环境质量评价标准;(2)叶菜类蔬菜对镉和汞的富集能力最强,部分叶菜中的镉和汞含量超过了食品中污染物限量标准;(3)研究区有约21.2%的蔬菜具有镉的潜在人体摄入风险,蔬菜中汞的风险概率约为1%,不同蔬菜镉和汞的人体摄入风险排序为叶菜根茎茄果;(4)不同蔬菜类型土壤镉和汞的环境质量基准值差异较大,因此在今后的标准修订时可考虑针对不同蔬菜类型分别制定设施菜地土壤重金属环境质量基准。  相似文献   

11.
针对滑坡发生的复杂性,该文把可变模糊集理论模型应用到滑坡稳定性评价中。选取4个层次17个因素建立了滑坡稳定性的多层次多指标评价单元系统。采用三级权重和二元比较模糊量化相结合的方法确定各影响因素权重。利用可变模糊识别模型对丹巴滑坡、老金山滑坡、印江岩口滑坡进行综合评价,评价结果与实际情况相吻合;并得到丹巴滑坡从20世纪80年代到2007年的稳定性先减弱后增强,在2004年3月到2005年3月处于最不稳定状态。可变模糊评价法与模糊综合评价法分别对丹巴滑坡a时期(20世纪80年代至1998年)、d时期(2005年3月到2007年)进行评价结果都为III级,验证了滑坡可变模糊识别评价模型的可行性。可变模糊模型利用动态可变的相对隶属度和级别特征值对丹巴滑坡a时期、d时期的特征值评价结果分别为3.27和3.44,评价出丹巴d时期稳定性比a时期稳定性差,进一步说明了可变模糊识别模型的优越性。滑坡稳定性评价可为滑坡灾害的防治和预警提供可靠的科学依据。  相似文献   

12.
固化/稳定化修复后土壤重金属稳定性及再活化研究进展   总被引:4,自引:1,他引:3  
常春英  曹浩轩  陶亮  吕贻忠  董敏刚 《土壤》2021,53(4):682-691
固化/稳定化技术是一种经济、有效、快捷的重金属污染主流修复技术,随着我国以风险管控为主导策略的土壤污染防治工作的推进,该技术正发挥着极其重要的作用。固化/稳定化技术处置后土壤中的重金属并未移除,存在再活化的风险。本文对固化/稳定化技术特点、修复效果评估方法、评价标准等进行了系统总结,概述了修复后重金属赋存形态、生物有效性、微观形态等特征,着重阐述了冻融、水环境和酸雨淋溶3类环境胁迫下重金属的再活化行为和影响因素。在此基础上,讨论了当前固化/稳定化修复后土壤和场地环境监管体系构建的现状、不足和发展需求,提出需注重修复后重金属环境行为、再活化定量化等研究方向。  相似文献   

13.
烟叶品质是反映和体现烟叶必要性状均衡情况的综合性模糊概念,其好坏不仅直接影响烟草产品的质量和效益,而且对烟草经济发展起着举足轻重的作用。研究基于模糊数学理论,应用模糊综合--加权平均模型,从烟叶香味、化学成分、燃烧性及农药残留等方面选取11项指标构建评价体系,对2003年重庆市烟叶品质进行了评价。结果表明:烟叶样本武隆2和酉阳1的隶属度远大于其它样本的隶属度,分别为0.695和0.630,说明两样本烟叶的品质最好;巫山2等多数烟叶样本的隶属度在0.1~0.2之间,样本烟叶品质次之;巫山1等烟叶样本的隶属度在0~0.1之间,样本烟叶品质相对较差。应用F分布法确定k次抛物线分布函数作为烟叶品质模糊综合评价的隶属函数,充分体现了烟叶品质评价本身的特点,而通过构建模糊综合一加权平均模型,可充分获取信息,对多样本进行比较排序,计算方法简便,评价结果可靠、合理。  相似文献   

14.

Purpose

In order to improve and support decision-making for the selection of remedial techniques for contaminated sites, a multi-criteria assessment (MCA) method has been developed. The MCA framework is structured in a decision process actively involving stakeholders, and compares the sustainability of remediation alternatives by integrating environmental, societal, and economic criteria in the assessment.

Materials and methods

The MCA includes five main decision criteria: remedial effect, remediation cost, remediation time, environmental impacts, and societal impacts. The main criteria are divided into a number of sub-criteria. The environmental impacts consider secondary impacts to the environment caused by remedial activities and are assessed by life-cycle assessment (LCA). The societal impacts mainly consider local impacts and are assessed in a more qualitative manner on a scale from 1 to 5. The performance on each main criterion is normalized to a score between 0 and 1, with 1 being the worst score. An overall score is obtained by calculating a weighted sum with criteria weights determined by stakeholders. The MCA method was applied to assess remediation alternatives for the Groyne 42 site, one of the largest contaminated sites in Denmark.

Results and discussion

The compared remediation alternatives for the site were: (1) excavation of the site followed by soil treatment; (2) in situ alkaline hydrolysis; (3) in situ thermal remediation; and (4) continued encapsulation of the site by sheet piling. Criteria weights were derived by a stakeholder panel. The stakeholders gave the highest weighting to the remedial effect of the methods and to the societal impacts. For the Groyne 42 case study, the excavation option obtained the lowest overall score in the MCA, and was therefore found to be the most sustainable option. This was especially due to the fact that this option obtained a high score in the main categories Effect and Social impacts, which were weighted highest by the stakeholders.

Conclusions

The developed MCA method is structured with five main criteria. Effect and time are included in addition to the three pillars of sustainability (environment, society, and economy). The remedial effect of remediation is therefore assessed and weighted separately from the main criteria environment. This structure makes interpretation of criteria scores more transparent and emphasizes the importance of effect and time as decision parameters. This also facilitated an easier weighting procedure for the stakeholders in the case study, who expressed a wish to weigh the remedial effect independently from the secondary environmental impacts.
  相似文献   

15.
快速城市化进程与工业发展,使得土壤污染日益严重。污染物进入土壤后,经水、气、生物等介质传输,通过饮水、呼吸、饮食、皮肤吸收等途径引起人体暴露,带来健康风险。污染土壤健康风险评估是制定土壤环境质量标准的基础,是一项新的环境管理技术与手段。我国污染土壤的健康风险评估还非常欠缺,为了推动其发展,本文讨论了其研究进展、方法、存在问题与发展趋势。当前,还缺乏准确定量的风险表征方法,评估过程中还具有较大不确定性。污染土壤的健康风险评估正在向多介质、多途径以及多种污染物暴露的方向发展,模型模拟的方法将会得到更多的应用。为了建立准确定量风险评估方法,在未来研究中需要加强对风险评估相关机理研究。这包括污染物的迁移传输规律、污染物的剂量一效应关系和人群生活方式等。  相似文献   

16.
基于可变模糊集理论的洪水灾害风险分析   总被引:4,自引:4,他引:4  
依据灾害系统理论,综合考虑洪水灾害系统的自然和社会属性,构建了洪水灾害风险综合评价指标体系,制定了相应指标的评价标准;在此基础上,以乡镇行政单元为基本评价单元,基于可变模糊集理论,采用可变模糊评价模型确定评价单元指标对各级指标标准区间的相对差异函数和相对隶属度,并通过变换组合参数进行综合评价,计算得到各评价单元的危险等级和易损等级,并结合风险等级分区矩阵,将研究区域划分为极高风险、高风险、中等风险、较低风险和低风险5个等级。最后,以荆江分洪区为典型研究区域,实例研究表明,该方法计算简便,评价结果可信度高,与实际调研情况一致,为洪水灾害风险评价提供了新思路,可推广到其他自然灾害的风险分析中。  相似文献   

17.

Purpose

Acid rain can accelerate the acidification of the chromium-contaminated soils, resulting in chromium releasing into soil solution and causing ecological risk. The current study aims to investigate the release of chromium in the remedied soils by Pannonibacter phragmitetus BB under the simulated acid rain leaching and to assess its risk to groundwater.

Materials and methods

P. phragmitetus BB was utilized to remedy the Cr(VI)-contaminated soils at two levels (80 and 1,276 mg kg?1) by the column leaching experiment, and the chemical remediation with ferrous sulfate was used as a control. The remedied soils by P. phragmitetus BB and ferrous sulfate were leached under the simulated acid rain to evaluate the release of chromium. Furthermore, the risk of chromium release from the remedied soils to the groundwater was assessed by a fuzzy comprehensive evaluation method.

Results and discussion

The average concentrations of water-soluble Cr(VI) in the remedied soils by P. phragmitetus BB were reduced to less than 5.0 mg kg?1. Under leaching situation with the simulated acid rain, the release of total chromium and Cr(VI) from the remedied soils by P. phragmitetus BB and ferrous sulfate declined rapidly with the extended leaching time. However, the release amounts of total chromium and Cr(VI) from the remedied soil by P. phragmitetus BB more efficiently deceased as compared with that by ferrous sulfate remediation. Carbonate-bounded, exchangeable, and organics-bonded chromium were the major chromium-releasing sources under the simulated rain leaching. After microbial remediation with P. phragmitetus BB and chemical remediation with ferrous sulfate, the risk grades of the remedied soils to groundwater declined from classes 11 to 5 and 6, respectively.

Conclusions

The risks of the remedied soils by both microbial remediation with P. phragmitetus BB and chemical remediation with ferrous sulfate to groundwater effectively decreased and microbial remediation more significantly declined the chromium risk to groundwater than chemical remediation.  相似文献   

18.

Purpose

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous and persistent contaminants in aquatic bed sediments. A better understanding of their in-bed fate and transport is therefore key in minimising the risk to the environment over time through various remediation and monitoring strategies. Since ecological effects and risks are related to contaminant concentrations, this study developed CoReTranS, a predictive model that simulates one-dimensional organic contaminant reaction and transport in bed sediments.

Materials and methods

CoReTranS was benchmarked against analytical solutions of simplified reactive transport models and validated using a published study of marsh sediments contaminated with petroleum-derived hydrocarbons from Wild Harbour, West Falmouth, MA, USA.

Results and discussion

The CoReTranS model effectively predicted the vertical distribution of PAHs in the Wild Harbour sediments as confirmed by the modelling results from the published study. The CoReTranS model was also used to interpret results from a published study of PAH-contaminated fjord sediments from Kitimat Arm in British Columbia, Canada. Specific insights into the post-depositional fate and transport of selected PAHs in the Kitimat fjord sediments were obtained by comparing the measured concentration-depth profiles with the numerical results from the CoReTranS model. Key parameters such as effective diffusivity of contaminants and burial velocities of sediment particles were shown to possibly account for the predicted concentrations-depth profiles in the Kitimat fjord sediments.

Conclusions

As demonstrated, CoReTranS can simulate reactive transport models in order to predict PAH concentration profiles in porewater under site-specific conditions. The information derived from the use of the CoReTranS model highlighted practical application of such information by engineers to site-specific risk assessment and remediation.  相似文献   

19.
An increase in energy demand leads to further exploration, transportation, and utilization of petroleum, which creates severe soil contamination because of recurrent accidents and oil spills. Remediation of these contaminated soils is challenging. Among many treatment methods practiced for remediation of petroleum-contaminated soils, surfactant-enhanced soil washing has been widely practiced as a preferred treatment option, as it is a fast and environmentally accepted method. In this paper, we review research undertaken on various anionic, nonionic, cationic, biological, and mixed surfactants for the remediation of petroleum hydrocarbon-contaminated soils. Upcoming surfactants like gemini and switchable surfactants are summarized. We assess the challenges and opportunities of in-situ and ex-situ soil washing, the mechanisms of surfactant-enhanced soil washing, and the criteria to follow for surfactant selection. Furthermore, we briefly discuss the operational and environmental factors affecting soil washing efficiency and soil and surfactant properties affecting surfactant adsorption. We also describe the advantages of coupling soil washing with effluent treatment and surfactant reuse challenges and opportunities. Moreover, challenges and possible new directions for future research on surfactant-enhanced soil washing are proposed.  相似文献   

20.
可变模糊集理论在旱涝灾害评价中的应用研究   总被引:1,自引:1,他引:0  
旱涝灾害是制约农业经济发展的最主要的自然灾害,旱涝灾害评价在农业防汛抗旱减灾决策中起着至关重要的作用.该文根据旱涝灾害的模糊不确定性,基于可变模糊集理论,确定样本指标对各级标准区间的相对隶属度,以山东省全年旱涝灾害为例,将可变模糊集理论应用于旱涝等级评价中,采用多种参数组合,可变模型(1个线性,3个非线性)进行评价,确定出样本的评价等级,并将其评价结果与模糊综合评价结果进行比较.应用实例表明,该模型计算简便,评价结果可信度高,为旱涝灾害的评价提供了参考.  相似文献   

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