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1.
林地外部效应评估研究势在必行   总被引:1,自引:0,他引:1  
单胜道 《资源开发与市场》2000,16(5):303-304,313
目前,国内外对林地外部效应评估的研究十分缺乏。此项研究不但有利于建立森林环境资源产业,完善国民经济核算体系,而且为合理确定林地资源效益补偿标准提供依据,并促进广义的森林环境资源市场体系的建立和林地资源的最佳配置。  相似文献   

2.
我国集体林权制度改革之后,林地细碎化程度不断加剧,农户的林地经营难度有所增加。林地细碎化、林地流转对林地资源配置效率的作用方式如何?基于福建省235户农户的调查数据,从林地细碎化、林地流转的角度分析了对林地资源配置效率的影响。结果表明:林地细碎化、林地流转对林地资源配置效率具有正向影响,户主年龄、户主身份、投资营林风险大小、林业劳动力占比、家庭总收入、林业收入占比、林地质量、申请采伐限额指标难易程度对林地资源配置效率具有显著的影响。  相似文献   

3.
农户对林地的生计依赖性同时受到农户家庭因素与外部社会环境的共同影响,由此构建了农户对林地生计的依赖性测算模型,并考察了农户对林地生计的依赖性与农户对林地流转意愿的关联性。利用福建省的农户调查数据,得到农户对林地生计的依赖度,并基于此对农户对林地生计的依赖性与他们对林地流转意愿的关联性进行了实证探讨。结果表明:农户对林地生计的依赖度在不同区间内的分布较不均衡,且农户对林地生计的依赖性较弱的农户数量所占的比重较高。同时,农户的林地流转意愿与他们对林地生计的依赖性表现出了较强的相关关系。这一研究结果证实了文中的两个基本假设:农户对林地的生计依赖性越强,农户的林地流入意愿越强,流出意愿越弱;农户对林地生计的依赖性越弱,农户对林地流出意愿越强,流入意愿越弱。  相似文献   

4.
厦门市污水林地生态处理工程   总被引:2,自引:0,他引:2  
文章介绍了厦门市狐尾山原生生活污水林地生态处理工程依循“污水-土壤-植物”资源再生机制,提出了“截流井+氧化塘(调节池)+污水动力输送、管网投配+林地+城市景观林地”的基本模式。  相似文献   

5.
集体林地使用权市场制度的建立与完善   总被引:6,自引:0,他引:6  
集体林地使用权市场将是我国南方集体林区土地市场发展的主要内容,它的健康发展需要一套制度来保障.在介绍集体林地使用权市场类型的基础上,分析了我国集体林地使用权市场制度的建设状况,并提出了今后急待建立和完善的林地使用权市场制度的主要内容.  相似文献   

6.
与农地相比,林地具有经营投入成本大、周期长,收益慢等特点,导致林地经营权抵押难以变现,严重影响了林地经营权抵押贷款的发展。现阶段国内外对农地抵押贷款的研究较成熟,而在林地方面还未形成完整的体系。通过梳理国内当前主要的农地经营权抵押贷款模式理论框架,对比分析三种主要模式,结合林地的特点,提出适合林地的经营权抵押贷款模式构建框架。该模式由贷款申请、资金补给、抵押品处置三个系统构成,克服了抵押品处置难、农信社贷款意愿低、资金来源渠道少等难题,提出了构建该模式的相关建议。  相似文献   

7.
通过分析当前森林生态补偿机制的各层面立法现状以及实践中形成的公益林登记模式与补偿资金专户管理模式,总结出在林地征占用中健全生态补偿机制的共有逻辑,并由此提出补充林地征地法律规范、规范相关程序、落实林地补偿分配机制等符合林地征占用补偿需求的生态补偿机制的应然路径。  相似文献   

8.
林地产权政策是决定资源配置效率的基础条件。对临安示范林地区研究基点河桥乡的林地产权政策、林地流转的基本情况及农户对林地产权的意愿进行了介绍,找出了现行政策存在的问题,并提出了一套科学合理的适合当地水平的林地产权政策方案。  相似文献   

9.
以晋西北黄土丘陵区岚县不同人工林地土壤水分为研究对象,分析了杨树、杏树、核桃3种不同树种的土壤水含量在垂直剖面的变化特征。研究表明,在0~600 cm深度的土壤中,随着土壤深度的增加,3种林地土壤水分含量呈现迅速减少然后缓慢增加再减少的波动趋势,土壤水分含量总体具有核桃林地杏树林地杨树林地;杨树林地土壤水分缺失度较大,核桃林地水分缺失度相对最小;干层发育严重程度表现为杨树林地杏树林地核桃林地。从3种植被对土壤水分的利用和破坏方面来看,核桃树更适宜作为该区商品林地的种植树种。  相似文献   

10.
学术界从不同角度对十八届三中全会以来的"三权分置"改革展开了讨论、研究,然而对"三权分置"的界定仍众说纷纭、缺乏共识,其背后潜在的问题与风险亦值得关注。林地是土地的重要组成部分,应坚持集体林地所有权,保护林地,保障林农的利益。但林地使用权"价值饱和"存在权属不清、流转不规范、主体单一等问题。通过"三权分置"制度的改革,对经营主体进行规制,明晰相关的权利属性,规范程序、完善司法救济,可最终实现林地使用权"价值饱和"。  相似文献   

11.
The characterization of total and leachable metals in foundry molding sands   总被引:1,自引:0,他引:1  
Waste molding sands from the foundry industry have been successfully used as a component in manufactured soils, but concern over metal contamination must be addressed before many states will consider this beneficial use. Since there is little data available on this topic, the purpose of this study was to characterize total and leachable metals from waste molding sands. A total elemental analysis for Ag, Al, As, B, Ba, Be, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, V, and Zn was conducted on 36 clay-bonded and seven chemically bonded molding sands. Total metal concentrations in the molding sands were similar to those found in agricultural soils. The leaching of metals (i.e. Ag, As, Ba, Be, Cd, Cr, Cu, Ni, Pb, Sb, and Zn) was assessed via the toxicity characteristic leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP), and ASTM water leach test. Based on the TCLP data, none of the 43 molding sands would meet the Resource Conservation and Recovery Act (RCRA) characteristic for toxicity due to high Ag, As, Ba, Cd, Cr, and Pb. Compared to the TCLP results, the metal concentrations were generally lower in the SPLP and ASTM extracts, which is likely related to the buffering capacity of the extraction fluids.  相似文献   

12.
海外石油项目的环境合规性管理意义重大,环境合规性管理的关键问题是识别合适的规范体系。从法学理论分析,资源国法律及其批准的国际公约、投资开发协议所要求的法律法规、金融机构的融资担保合同中所要求的法律法规、投资母国的法律规范构成了对海外石油项目的硬法约束;国际组织通过约束跨国公司行为的协定指南、企业加入的自愿性承诺、国际行业标准以及被视为最佳实践和惯例的标准导则构成了软法约束。本文结合主要国际石油公司的环境合规性实践分析,认为在实际管理中,可以根据规范来源与效力、企业追求目标等因素将上述规范区分为核心规范和其他规范,其中核心规范进一步区分为必选规范和可选规范。  相似文献   

13.
ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.  相似文献   

14.
Urban ecological systems: scientific foundations and a decade of progress   总被引:9,自引:0,他引:9  
Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.  相似文献   

15.
本电子设备安全性设计的目的就是通过识别、分析、评价系统中存在的危险性,预计事故对人员、设备和环境的破坏的可能性和严重性,根据其结果调整工艺、设备、操作、管理、生产周期和投资等因素,提出消除、减少、控制危险及危险事件的措施,以便使事故在发生之前得到控制,降低系统运行的风险。  相似文献   

16.
After a century of major technicaladvance, essentially achieved by and for theindustrialized countries, the evolution of thefood sector in southern countries should nolonger be thought of in terms of a ``headlongpursuit.'' In the present context of demographicgrowth, urbanization, poverty and disparities,environmental degradation, and globalization oftrade, new priorities have emerged, and newethical questions have been raised, mainlyrelated to sustainability and equity. Thispaper analyses these ethical concerns in thefollowing terms: can the model of food sectordevelopment initiated by the industrializedcountries be applied to the entire world on asustainable and equitable basis, given theeffects of this development with regard to theenergy consumed, the changes in dietarybehavior and related nutritional problems, thenew demands in terms of food safety, thequestions of biodiversity, ownership ofknowledge, cultural identities, gender issues,and Man's relationship to food and Nature?  相似文献   

17.
The microbiological and physico-chemical characteristics of the drinking water supplied by the Central Borehole at the University of Benin, Ugbowo Campus were investigated. The investigation entailed assessment of the pH, turbidity, total suspended solids, total dissolved solids, dissolved oxygen, temperature, salinity, conductivity, nitrate, nitrite, phosphate, sulphate, chloride, N-nitroso compounds, cadmium, chromium, nickel, lead, zinc, manganese, iron, coliform count, BOD5 and COD of the water at the Central Borehole and at ten residential quarters. The assessment indicated that the water was fit for drinking and other domestic applications. Results were also compared with WHO, EU and Nigeria FEPA standards. The results showed that the pH values of the water (5.01–5.86) and total coliform count (1–2/100 ml) expressed as MPN were outside the limits set by the WHO, EU and FEPA. The data also showed that the other water quality parameters assessed were within WHO, EU and FEPA permissible limits. The results of ANOVA showed that significant changes occurred during distribution.  相似文献   

18.
Capoterra Pond in southern Sardinia is described and analyzed with respect to its morphological, meteorological, physical and chemical characteristics, and its zoobenthic, zooplankton, and phytoplankton biocenoses. The birdlife, flora, and riparian associations of vegetation are studied in order to draw international attention to the importance of this lagoon, the precariousness of its ecosystem, the seriousness of current attempts to destabilize it, and the need to encourage the Sardinian authorities to initiate conservation measures, especially as rare birds have found their niches there.  相似文献   

19.
Future technological developmentsconcerning food, agriculture, and theenvironment face a gulf of social legitimationfrom a skeptical public and media, in the wakeof the crises of BSE, GM food, and foot andmouth disease in the UK (House of Lords, 2000). Keyethical issues were ignored by the bioindustry,regulators, and the Government, leaving alegacy of distrust. The paper examinesagricultural biotechnology in terms of a socialcontract, whose conditions would have to be fulfilled togain acceptance of novel applications. Variouscurrent and future GM applications areevaluated against these conditions. Successwould depend critically on how far a sharedvision can be found with the public. Tore-establish trust, significant changes areidentified in the planning and pursuit ofbiotechnology.  相似文献   

20.
随着绕城高速公路的建设,国内大城市高速走廊效应日益显著.以山东济南市东绕城高速公路为例,利用SWOT分析方法阐述了绕城高速公路走廊发展的基础条件,明确了产业发展的思路和定位.最后,在总结分析结构提升、重点突破、组团布局、集群发展、品牌联动五大战略的基础上,提出了产业走廊发展所需的人才、科技、投资、资源、基础设施等六大支撑体系.  相似文献   

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