生态足迹研究现状及基于净初级生产力的计算方法初探

生态足迹是一种有效的再生资源更新能力的定量测度方法,其主要用于评估给定年,给定技术条件下生物圈的再生能力能否满足人类消费需求。本研究对国内外生态足迹模型的理论假设、生态足迹、生物承载力、生态盈余、生态赤字进行了简要介绍;在对国际组织发布的生态足迹报告以及生态足迹文献发表情况进行统计的基础上,回顾了国内外的生态足迹计算方法——基于净初级生产力的计算方法,并与现有的基于全球农业生态区的计算方法进行了比较,探讨了两种方法的优缺点;最后对生态足迹今后的研究重点提出了一些看法和展望。     

Introduction: Natural Capital, Poverty and Development

Can development occur without running down natural resources in an unsustainable way? The concept of natural capital offers a way for those with divergent views (ecologists and economists for example) to discuss this difficult question. Four aspects are examined in detail. First, the role of institutions in facilitating sustainable development is discussed, with examples from forestry. Then examples from (eco)tourism illustrate the potential – and limits – of applicability of the concept. Measurement issues for natural capital are then considered in detail. Finally, the concept is applied to agricultural strategy in fragile lands, where the tradeoff between the environment and development is likely to be most severe. Some implications for future research and policy are developed.     

征收碳税对中国经济影响的实证

近年来,中国CO2排放置显著增加,已引起社会各界的广泛关注.碳税作为最有效的经济手段之一,适时开征,不仅是我国应对气候变化、节能减排的要求,也是中国承担相应的国际责任的要求.本文根据中国各省(市、自治区)能源消费量及相关系数对相关能源产品使用产生的CO2排放量进行了核算,并依据国际实践经验拟定了三种不同情景的碳税税率.利用1999 - 2007年间的省际面板数据,通过面板数据模型定量分析了征收碳税对中国经济的影响,特别是对经济增长、能源消耗影响.研究表明:①征收碳税会降低社会总产出,对经济增长具有消极影响,从长期看,随着碳税体制完善,税率逐步提高,这种消极影响将逐渐减弱;②征收碳税可以提高能源的产出效率,降低能源要素的使用,减少CO2的排放;③碳税税率提高会减小劳动和资本要素之间的收入分配差距.因此,碳税开征具有明显的节能减排效果,且能有效地调整要素间收入分配.但是受中国现阶段经济发展水平的制约,碳税对中国经济冲击较大,短期内暂不适合开征.     

Radionuclide transfer to fruits: a critical review. Introduction

This paper provides a brief introduction to fruit, their definition, classification and geographical distribution. In the following review, the term "fruit" refers not to a well-defined botanical plant part but, in the horticultural sense, to a component of the human diet generally consumed as a dessert item. Plants that bear fruits cover a vast range of morphological and physiological traits. A generic classification of fruit-bearing plants is proposed for use in studies on radionuclide transfer to fruit.     

Introduction of geomechanical restoration method and its implications for reservoir assessment of unconventional oil-gas resource in China

New technologies are in urgent need of unconventional hydrocarbon exploration and development in China.This paper provides a brief introduction and analysis of a new three-dimensional(3D)geomechanical restoration method developed in recent years.After an in-depth discussion on the technical principle and specific characteristics of the fields,we designed a feasible workflow for two oil-gas fields with great unconventional oil-gas resource potentials in China(Weiyuan and Jiulongshan oil-gas fields of Sichuan).After discussing the major challenges and limitations of the new technology,we also suggest its research efforts and future application prospect It is shown that the new technology will be an effective method to facilitate the exploration and development of unconventional oil and gas resources in China.     

Introduction to and experimental conditions during the first year of the GMR chronic inhalation studies of diesel exhaust

A chronic exposure study was initiated to determine the effects of diesel exhaust on the health of experimental animals. For this purpose, test atmospheres of clean air (control) or freshly diluted diesel exhaust at concentrations of 250, 750, and 1500 μg/m³ were supplied to four 12.6 m³ inhalation chambers which housed rats and guinea pigs. Diesel aerosol size and concentration, as well as chamber temperature and relative humidity, were continually monitored and controlled to maintain the exposure dose levels and an environment of 22±2°C and 50%±20% relative humidity. The concentrations of CO and NO_x were found to be 5.8±1.0 mg/m³ and 7.9±1.0 mg/m³ above ambient in the chamber containing 1500 μg/m³ of particulate. Animals were supplied from the chambers, on a random basis, for both intramural and extramural studies throughout the exposure period. The experiment ran uninterrupted for over twelve months with mean diesel particle mass concentrations within 2% of the target values.     

Effect of Climatic Factors on the Growth of Representatives of the Genus Pinus (Pinaceae) under Conditions of Introduction

Four introduced and one aboriginal species of the genus Pinus L. have been studied in the middle taiga subzone of southern Karelia. Significant interspecific differences in the dates of onset, cessation, and peak of the growth of shoots and needles have been revealed. It has been shown that their annual increment depends on the rate of growth, rather than on its duration. The dynamics of shoot and needle growth in introduced and aboriginal species, though largely similar, differ in some respects. These differences reflect species-specific responses to hydrothermal conditions in a certain growing season.     

Introduction of a recycling system for sustainable municipal solid waste management: a case study on the greater Banjul area of the Gambia

This research proposes for the introduction of a recycling system in the Gambia to enhance sustainable municipal solid waste management. Poor infrastructures, coupled with inadequate resources and lack of funding, work against the optimization of a MSW disposal service. In the authors’ view, authorities in charge of waste management need to change not only behaviors, but modernize their processes. Recycling technology is a key part of the solution. A model has been developed which suggest the involvement of stakeholders to achieve meaningful sustainable MSWM. This can be achieved by recognizing the role of the informal sector through community-based organizations, Non-Governmental Organizations (NGOs), and the private sector. The open dump approach is leading to severe environmental consequences as the groundwater and soil within the dump is been contaminated. In this study, an integrated municipal solid waste management approach was developed with a model to help achieve sustainable municipal solid waste management. Resource recovery, not waste disposal, must be the ultimate goal with clearly defined end user markets so that the recovery loop is complete. Mandatory sorting of waste at household level would help greatly in making recycling activity successful.     

Natural outdoor environments and mental and physical health: Relationships and mechanisms

BackgroundEvidence is growing for the beneficial impacts of natural outdoor environments on health. However, most of the evidence has focused on green spaces and little evidence is available on health benefits of blue spaces and about possible mediators and modifiers of such impacts. We investigated the association between natural outdoor environments (separately for green and blue spaces) and health (general and mental) and its possible mediators and modifiers.MethodsCross-sectional data from adults interviewed in Catalonia (Spain) between 2010 and 2012 as part of the Catalonia Health Survey were used. The collected data included sociodemographic characteristics, self-perceived general health, mental health, physical activity and social support. Indicators of surrounding greenness and access to natural outdoor environments within 300 m of the residence and degree of urbanization were derived for residential addresses. Associations were estimated using logistic regression and negative binominal models.ResultsGreen spaces were associated with better self-perceived general health and better mental health, independent of degree of urbanization. The associations were more consistent for surrounding greenness than for access to green spaces. The results were consistent for different buffers, and when stratifying for socioeconomic status. Slightly stronger associations were found for women and residents of non-densely populated areas. No association was found between green spaces and social contacts and physical activity. The results for blue spaces were not conclusive.ConclusionGreen spaces are associated with better general and mental health across strata of urbanization, socioeconomic status, and genders. Mechanisms other than physical activity or social support may explain these associations.