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201.
介绍了国内外MOFs材料吸附去除废水中各种污染物的研究进展,主要针对重金属离子(Hg2+、U6+、Cr6+、Cd2+、Pb2+、Co2+、Sb5+、Sr2+)及类金属离子(As3+、As5+)、有机污染物(染料分子、芳香化合物)等的去除,分析了MOFs及改性MOFs材料对废水中污染物的吸附性能;展望了MOFs材料在废水污染物吸附治理中的应用前景,提出高稳定性及具有催化性质的MOFs材料是用于废水中污染物吸附治理的理想材料。  相似文献   
202.
统一用途管制是自然资源管理的宏观核心目标。目前自然资源用途管制中仍存在事权划分不清、管制指标维度不一、管制空间重叠、监督评价不足等问题,需从管制逻辑框架和系统构成的层面进行综合研究。逻辑框架法是一种从问题出发,将宏观目标转换为具体目标和措施的有效方法。借助逻辑框架法思路,在分析自然资源用途管制基本内涵的基础上,建立自然资源用途管制的“宏观目标—具体目标—问题提出—管制措施—评价监管”的逻辑框架关系,同时在自然资源用途管制具体措施和评价监督等方面提出相关建议。  相似文献   
203.
水—能源—粮食纽带关系若干问题解析   总被引:1,自引:0,他引:1  
水、能源、粮食均为战略性、基础性资源,三者之间相互关联,彼此制约,深刻影响着人类的生产、生活和生态环境。通过梳理水—能源—粮食纽带关系领域的研究内容、研究方法、研究尺度等,进一步明确了变化环境影响下水—能源—粮食纽带关系概念框架及其风险关系的传递与表达,指出当前对水—能源—粮食纽带关系理解尚未统一,广泛采用的有“联系论”和“方法论”。现有研究对水—能源—粮食纽带关系进行了现状评估,资源间相互消耗关系的量化与不同情景下的仿真模拟。研究中存在数据缺失、不一致,评估因素单一,缺少动态反馈机制,难以真正应用到政策调控中等问题。因此,数据整合、模型集成、风险评估与动态调节、提高韧性、城市尺度研究和智慧管理,均是水—能源—粮食纽带关系发展关注的重点领域。  相似文献   
204.
An agent-based model was used to evaluate the response of a two-species fish community to fishing boat exploration strategies, namely: boats following high-yield boats (Cartesian); boats fishing at random sites (stochast-random); and boats fishing at least exploited sites (stochast-pressure). At low fishing pressure, the stochast-random mode yielded a high average catch per boat while sustaining fish biomass. At high fishing pressure, the Cartesian mode was more effective. For the Cartesian strategy, fish biomass exhibited four distinct behaviors with increasing number of boats. In the first phase, the fish biomass dropped with increasing number of boats due to a corresponding rise in biomass extraction. Rapid exploitation occurred in the second phase, when two or more boats occupied the same initial area, that led to the faster abandonment of those sites which then underwent biomass recovery. In the third phase, adding more boats resulted in a fluctuating stock biomass, where the combined effects of initial spatial distribution of boats and rapid localization led to either full stock recovery when boats were eventually confined to a single location due to spillovers, or stock extirpation when the entire area became fully occupied. Beyond the third phase, stock extirpation was assured. In order to break the pattern of localization (bandwagon effect), we introduced stochast-random intruders in a Cartesian-dominated fishery. Adding a single intruder changed the patchy-structured stock biomass pattern of a purely Cartesian fishery to a uniformly explored stock biomass pattern because of the additional spatial information provided by the intruder. Consequently, the average catch per boat increased but at the expense of a disproportionate decline in equilibrium biomass.  相似文献   
205.
We study how society's preferences affect the resilience of economies that depend on more than one type of natural resource. In particular, we analyze whether the degree of complementarity of natural resources in consumer preferences may give rise to multiple steady states and path dependence even when resources are managed optimally. We find that, for a given social discount rate, society tends to be less willing to buffer exogenous shocks if resource good are complements in consumption than if they are substitutes. The stronger the complementarity between the various types of natural resources, the less resilient the economy is, and even more so the higher is the social discount rate.  相似文献   
206.
In Switzerland, communities are encouraged to define and to report on local Agenda 21. This paper presents an analysis framework to help local communities set sustainable development priorities and to follow through with appropriate actions. Four Swiss communities, from the French-speaking part of Switzerland, actively follow the project: Lausanne (114 304 citizens), Vevey (15 364 citizens), Mannens-Grandsivaz (505 citizens) and Essertines/Yverdon (666 citizens). The analysis framework developed is constituted of four interdependent fields: the societal characteristics, the individual or collective behaviours, the end objectives or sustainability impacts and the inhabitant's perception of these three fields. The link between society and behaviour can be studied through sociological analyses. The link between behaviour and environmental impact can be established thanks to Life Cycle analysis and Input/Output analyses. At each level, sustainable development indicators can be defined. As an application of the framework, the citizen energy consumption has been studied and expressed in energy slaves (= 3150 MJ/Year). A Swiss citizen needs altogether 69 slaves, 20 for his private consumption of goods and services, 19 for housing, 11 for transport, I1 for food and 8 for his consumption of public goods. If one fifth of the inhabitants of Lausanne, wanting to live closer to nature, actually moved out of town, the region would need 10 436 more slaves for 3500 persons happily living in the countryside.  相似文献   
207.
Multimedia environmental modeling is extremely complex due to the intricacy of the systems with the consideration of many related factors. Traditional environmental multimedia models (EMMs) are usually based on one-dimensional and first-order assumptions, which may cause numerical errors in the simulation results. In this study, a new user-friendly fuzzy-set enhanced environmental multimedia modeling system (FEEMMS) is developed, and includes four key modules: an air dispersion module, a polluting source module, an unsaturated zone module, and a groundwater module. Many improvements over previous EMMs have been achieved through dynamically quantifying the intermedia mass flux; incorporating fuzzy-set approach into environmental multimedia modeling system (EMMS); and designing a user-friendly graphic user interface (GUI). The developed FEEMMS can be a useful tool in estimating the time-varying and spatial-varying chemical concentrations in air, soil, and groundwater; characterizing the potential risk to human health presented by contaminants released from a contaminated site; and quantifying the uncertainties associated with modeling systems and subsequently providing robustness and flexibility for the remediation-related decision making.  相似文献   
208.
为了厘清主要经济地理要素与城市群工业污染物排放量的关系,引入新经济地理学3D——density(密度)、distance(距离)、division(分工/分割)框架,并采用该框架系统分析主要经济地理要素与长三角城市群污染物排放量之间的关系. 结果表明:①地均GDP对长三角城市群工业污染物排放量均存在显著影响,与工业SO2、废水和烟粉尘排放量的弹性系数分别为0.027、2.080和1.014. ②综合交通距离对工业废水和烟粉尘排放量存在显著影响,弹性系数分别为-1.638和-0.625,而心理距离对污染物排放量未产生显著影响. ③分工/分割要素对城市群工业污染物排放量的影响各不相同. 外商直接投资对工业SO2、废水、烟粉尘排放量存在显著影响,制造业专业化指数仅对工业SO2和烟粉尘排放量有显著影响,而进出口总额占GDP比重与工业废水和烟粉尘排放量存在显著影响. ④长三角城市群工业污染物排放量与地均GDP、外商直接投资呈正相关,与综合交通距离、制造业专业化指数和进出口总额占GDP比重呈负相关,缓解长三角城市群工业污染物排放困境,不仅要适度控制经济发展速度和提高外资进入的环境标准,还应进一步优化长三角城市群在国内外市场上的分工和协作地位.   相似文献   
209.
Due to rapid socioeconomic development in recent years, the influence of human activities on the urban ecosystem and environment is becoming more pronounced, causing increases in accumulated pollutants, resource consumption, and built-up land area. At this time, cities are facing complex ecological threats. We designed a platform to classify and assess the various types of ecological risks that cities and urban agglomerations may encounter. We used PHP to develop a web-based application, with nginx as the platform server, and MySQL to manage the background database. The platform provides users with a clearly structured, visual platform to manage ecological risk. By using this platform, users can quickly identify regional risk sources, find and describe risk factors, and predict possible consequences caused by these risks based on simulation modeling. The forecasting model and database can be synchronously updated and adjusted according to the actual situation. The visual web management platform and user security login system employ the MD5 encryption algorithm. The platform is designed to provide convenient, accurate, and scientific decision-making services for urban planning, construction, environmental protection, and other related areas.  相似文献   
210.
根据水污染流动"源头-转化-汇入"过程,综合衡量工业、农业、生活源污染排放对成都市主要河流的环境影响,提出"驱动力D (人口、社会经济发展)-承载源C (工业、农业、生活源污染排放)-承载状态S (污染程度)-管理M (治理污染投资)"4个子系统的DCSM模型,构建包含3层结构26个指标的成都市河流水环境承载力综合评价指标体系.采用投影寻踪模型得到各指标的影响程度,进一步建立区域水环境承载力各评价指标权重,根据最佳投影方向确定成都市主要河流2014—2018年的水环境承载力综合评价特征值,并得到相应评价等级.研究结果表明:影响程度最大的3项指标依次为:工业源COD排放强度、国考断面地表水TP平均浓度、环保投资占GDP的比重;通过对各个指标的权重分析,表明承载状态子系统和承载源子系统对综合评价结果所起作用最为显著,其次是管理子系统,驱动力子系统作用最小;通过评价等级分析,结果表明:2014—2018年成都市河流水环境承载力综合评价指数逐渐增加,评价等级从Ⅲ级(一般,2014—2016年)转变为Ⅱ级(较强,2017—2018年),说明5年来成都市河流水环境承载力逐步增加.研究表明了基于DCSM模型的成都市河流水环境承载力综合评价结果具有实用性和可行性,可以为城市河流水环境承载力综合评价提供新的研究思路,为水环境规划与管理的科学决策提供依据.  相似文献   
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