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1.
讨论了自然遗产的概念,通过对自然遗产概念的讨论进一步分析了自然遗产的特征并对自然遗产进行了分类,最后对自然遗产与文化遗产、自然遗产与地质遗迹进行了辨析  相似文献   

2.
农药对鸟类的毒性及其安全性评价   总被引:2,自引:0,他引:2  
阐述了农药对鸟类的急性毒性 ,探讨了农药对不同鸟类的毒性以及不同农药品种、不同农药剂型对鸟类的危害影响 ,并就农药对鸟类的安全性进行了评价  相似文献   

3.
微纳米塑料(MNPs)在水环境中的污染问题已成为全球关注的热点。MNPs因其数量多、粒径小,极易被鱼类误食对鱼体造成危害。本文综述了MNPs对鱼类毒性效应及作用机制,首先阐述了鱼类对MNPs的摄食、富集和转运规律,分析了不同粒径的MNPs对鱼类造成的不同危害,其次重点评述了MNPs对鱼类毒性效应及作用机制,并介绍了MNPs和其他污染物对鱼类的毒性效应,最后展望了MNPs对鱼类的研究趋势。研究MNPs对鱼类毒性效应及作用机制有利于增进对MNPs的生态毒性的认识,为经济鱼类的安全生产和生态稳定提供科学依据。  相似文献   

4.
基质对于人工湿地净化磷素潜能的探讨   总被引:18,自引:0,他引:18  
晏再生  王世和 《生态环境》2007,16(2):661-666
综述了不同基质对于人工湿地净化磷素的潜能的研究结果。总结了不同基质对磷素的理论最大吸附量以及基质在人工湿地运行中对磷素净化能力,探讨了影响基质对磷素吸附性能的几个主要因素,并对今后在人工湿地基质类型的选择方面提出了展望。  相似文献   

5.
考察了雪硅钙石对水中的重金属Hg2+离子的吸附性能,通过单因素实验及正交实验,研究了试水的pH值、初始浓度、吸附时间、吸附温度等因素对雪硅钙石吸附Hg2+反应的影响,确定了优化吸附条件.测定了雪硅钙石对Hg2+的吸附等温线,并用Langmuir吸附等温式进行了拟合,计算了吸附热力学参数,并对其吸附动力学过程进行了分析计算.  相似文献   

6.
对广东省平远县稀土矿开采对土地资源的影响进行了初步的调查和分析。同时在已进行的植被恢复措施的基础上,对其效应作了初步的分析,评价了恢复措施对水土流失和土壤理化性质的影响,并据此提出了比较适合的植被恢复措施。  相似文献   

7.
随着纳米材料生物安全性及纳米毒理学相关研究的深入,纳米尺度物质对心血管系统的潜在危害受到极大关注.论文综述了纳米尺度物质对心血管系统影响的流行病研究和实验研究的最新进展,探讨了纳米尺度物质对心血管系统影响的分子机制,提出了心血管系统是纳米尺度物质所致毒性效应的主要靶点之一的观点,在此基础上对纳米尺度物质对心血管系统影响研究的发展方向进行了展望.  相似文献   

8.
国内外乡村聚落生态研究   总被引:3,自引:0,他引:3  
为深入开展对乡村聚落生态学的研究,对我国传统的聚落生态思想进行了回顾,并对国内外有关乡村聚落生态的研究进行了述评。  相似文献   

9.
根据对河西走廊中部荒漠植被的调查,对荒漠植被进行了分类及生态学描述,重点讨论了荒漠植被对改善河西走廊中部农村生态环境的作用,提出了保护和利用荒漠植被的措施及改善生态环境的途径。  相似文献   

10.
我国大气环境毒理学研究新进展   总被引:2,自引:0,他引:2  
对大气环境中重要污染物的毒理学作用及其机制方面的文献进行综述。首先,总结了细颗粒物(PM2.5)和纳米颗粒物对呼吸系统和心血管系统毒理学作用及其机理方面的研究;然后,评述了二氧化硫(SO2)对基因表达的影响及内源性SO2生理作用方面的研究,提出SO2既是一种全身性毒物,又是一种新型信号分子的新观点;对大气环境致癌物,特别是有关苯并芘致癌作用分子机制的研究进行讨论;对大气中臭氧和光化学烟雾对健康影响的研究作了评述;最后,对室内空气污染物尤其是甲醛的毒性作用及其机理方面的最新研究进行了评论。  相似文献   

11.
1999年3月衡阳市动物园饲养的1只13岁云豹,出现严重的脱毛症状,经寄生虫学检查、饲料营养成分检测以及诊断性治疗等综合分析诊断为缺乏微量元素和维生素引起的脱毛症.在饲料中添加微生素和富含矿物质的添加剂,通过3个月的治疗该云豹完全康复.  相似文献   

12.
Recovery of depleted populations is fundamentally important for conservation biology and sustainable resource harvesting. At low abundance, population growth rate, a primary determinant of population recovery, is generally assumed to be relatively fast because competition is low (i.e., negative density dependence). But population growth can be limited in small populations by an Allee effect. This is particularly relevant for collapsed populations or species that have not recovered despite large reductions in, or elimination of, threats. We investigated how an Allee effect can influence the dynamics of recovery. We used Atlantic cod (Gadus morhua) as the study organism and an empirically quantified Allee effect for the species to parameterize our simulations. We simulated recovery through an individual‐based mechanistic simulation model and then compared recovery among scenarios incorporating an Allee effect, negative density dependence, and an intermediate scenario. Although an Allee effect significantly slowed recovery, such that population increase could be negligible even after 100 years or more, it also made the time required for biomass rebuilding much less predictable. Our finding that an Allee effect greatly increased the uncertainty in recovery time frames provides an empirically based explanation for why the removal of threat does not always result in the recovery of depleted populations or species. El Efecto Allee y la Incertidumbre de la Recuperación de Poblaciones  相似文献   

13.
The search for a balance between nature conservation and tourism development within protected areas is becoming an increasingly multifaceted problem worldwide, as outlined by an increasing number of authors and highlighted at several international events. Since it is unlikely that all management objectives will reach their optimum values simultaneously, an optimization approach is required to meet multiple, conflicting goals and to obtain an overall trade-off in terms of the conceived objectives.  相似文献   

14.
The construction of an ecocity is gradually gaining attention as an indicator of sustainable development. Genuine saving rate (GSR), which takes account of various impacts of economic activities including depletion of natural resources, costs of environmental pollution and long-term environmental damage, can be used as an integrated indicator to measure the status quo and potential of sustainability for an ecocity. This paper discusses the concept of an ecocity; and analyses the time-series of GSR in Suzhou between 1991–2001 as a case study used to develop a standard method of measuring sustainability. The status quo and trends in urban sustainability in six case study cities in China are then evaluated and compared. The results show the current status: Suzhou (23.6%), Guangzhou(18.9%), Ningbo (14.7%), Yantai (13.1%), Yangzhou (11.7%) and Sanming (7.9%). The study demonstrates that GSR provides not only a linkage by which local governmental departments for resources management, environmental protection, finance and planning can be connected directly, but also an effective analytical tool for the planning and construction of an ecocity as well as decision-making support for local governments.  相似文献   

15.
河流作为自然界的一部分,是人类文明的摇篮,也是人类活动的重要区域.河岸带是河流生态系统的重要组成部分,在维系生态平衡中发挥着巨大作用.本文以南渡江河岸带生态修复为例,提出了河岸带的3种生态修复策略和5种生态修复模式,并对未来河流生态修复重点提出了相关建议,以期为国内河流生态修复与综合管理提供参考与借鉴.  相似文献   

16.
姜加虎  黄群  孙占东 《生态环境》2004,13(4):694-697
保护具有重要生态功能地区的生态环境,是我国实施可持续发展战略的重要措施。洞庭湖是长江流域极重要的调蓄滞洪区,在维系长江江湖水系和水域生态平衡等方面,发挥着巨大的作用,是国家进行生态功能保护区建设的重点地区之一。文章对洞庭湖生态功能保护的必要性和效益进行了分析和评估。  相似文献   

17.
When consumers exhibit present bias, the standard solution to market failures caused by externalities—Pigouvian pricing—is suboptimal. I investigate policies aimed at externalities for present-biased consumers. Optimal policy includes an instrument to correct the externality and an instrument to correct the present bias. Either instrument can be an incentive-based policy (e.g. a tax on fuel economy) or a command-and-control policy (e.g. a fuel economy mandate). Under consumer heterogeneity, a command-and-control policy may dominate an incentive-based policy. Calibrated to the US automobile market, simulation results suggest that the second-best gasoline tax is 3–30% higher than marginal external damages. The optimal price policy includes a gasoline tax set about equal to marginal external damages and a fuel economy tax that increases the price of an average non-hybrid car by about $550–$2200 relative to the price of an average hybrid car.  相似文献   

18.
Water reuse and wastewater minimization are becoming increasingly important strategies for industrial parks. However, integrated industrial water management systems at an industrial park level have not yet been adequately investigated to determine synergies. This paper employs a case study of the Tianjin Economic Development Area (TEDA) to examine the importance of developing an integrated water resources management framework at the industrial park level. The paper presents a framework for effective and efficient management of water resources within an industrial park by taking a systems approach to conventional water management practices, designed to minimize industrial water use and maximize wastewater reuse among different tenants of an industrial park. The framework is composed of four elements: a management information system, policies and regulations, economic instruments and capacity building. The paper then considers how to implement such an integrated approach.  相似文献   

19.
Summary. 22-Acetyl-20-hydroxyecdysone was identified as a major component in the secretion of elytral and pronotal glands of Chrysolina carnifex, at an estimated concentration of 1.5 x 10-1 M. This unexpected high concentration of an ecdysteroid in an exocrine secretion of an insect is discussed in terms of its potential defensive function, and in the light of steroid production in similar glands of closely related leaf beetles.  相似文献   

20.
废水处理新技术中的超临界水氧化法   总被引:20,自引:1,他引:19  
超临界水氧化法是一种有效处理有机废水的方法,本文在总结超临界水的特点和优点的基础上,着重介绍了超临界水氧化的基本原理,工艺流程及应用状况,探讨该项技术的前景与发展趋势。、  相似文献   

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