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61.
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.  相似文献   
62.
New institutional economists have argued that there are many categories of institutions, including market and non-market institutions, which may prove economically efficient, specifically for public goods and common pool goods. The Government of India introduced a non-market community-based institution, known as Joint Forest Management (JFM), for forest management and protection in 1990. JFM is a sharing mechanism for forest planning and management based on sharing of rights and duties, control and decision-making authority over forestlands, between forest departments and local user groups. By 2001, 42 000 Village Forest Committees established under JFM were managing over 11.5 million ha forestland. These institutions have proved very useful, and have contributed to forest management as well as four aspects of sustainable human development (SHD) – ecological output, income generation, village infrastructure development, and community empowerment. In the long-term, community-based institutions will prove to be a foundation of SHD and participatory democracy.  相似文献   
63.
The incapacity to finance sustainable development through philanthropic official assistance turned the Johannesburg Summit to business world and the financial industry. Pioneering financial institutions – including development banks and private banks – have developed a wide range of innovations that can support sustainable development. This article highlights a few innovative products and markets and focuses on the progress made by financial players on the level of standards, metrics and guidelines to improve sustainability management systems, reporting and accounting practices and the multi-stakeholder dynamic. The role of the socially responsible investing (SRI) community has been underexposed by the Summit. Through its voice and market success, SRI has moved from a green market niche to the mainstream, however not becoming mainstream. The invaluable levering effect of SRI has just been discovered by authorities and market regulators and is becoming instrumental. In order to show the business case of Corporate Social Responsibility and to prove the financial viability of the People, Planet, Prosperity investing approach, the SRI community should critically reflect on its own quality assurance systems, sound disclosure and verification practices.  相似文献   
64.
ABSTRACT: The cries of pending water crises are usually cast in terms of water availability and/or water quality. Unfortunately, the real factors underlying a perceived crisis are often overlooked and the solutions prescribed are fax from optimal when measured in either economic or social terms. Today's technology outstrips its implementation, yesterday's solutions are imposed on a new breed of problems, and a static game is being played in a dynamic world. There is a need for the application of innovative and revolutionary tactics, for modernizing institutions, and for educating technologists and decision makers alike in the art of communicating their views and skills. This is the challenge. If it is met, some predicted crises will not materialize, and many others will be diminished in scale. An exciting opportunity exists to extend the boundaries of a new era in water management.  相似文献   
65.
In line with the resource curse literature, this paper examines the effect of oil dependency on the disparities in access to electricity between urban and rural areas in Africa, conditional on the quality of political institutions. Based on data from 36 African countries over the period 2000–2017, our investigation suggests that oil rents (% of GDP) increase urban–rural disparities in access to electricity. However, the quality of institutions shapes the effect of oil dependency on these disparities. Specifically, a 10% increase in the institutional quality score reduces the adverse effects of oil rent on electricity access disparity by around 19%, and the negative impact of oil dependency on urban–rural disparities is reversed when institutional quality reaches a score of 52% on a scale from 0 to 100. The robustness tests support these results and call for strengthening the quality of institutions to overcome the resource curse in Africa.  相似文献   
66.
在实验室恒流--修复微生态系统中,通过健康水体来对武汉东湖污染程度不同的水体进行持续替换,以模拟受不同程度污染胁迫的自然水体恢复过程,其间定期测定微型生物群落的中结构和功能参数,通过其变动机制和规律,再现修复过程中微型生物群落的演替过程,并从生态学角度提出了东湖5个受到不同程度污染水体得到修复的换水库。  相似文献   
67.
High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality.This is especially true for highly urbanized region with complex terrain and land-use.This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka,Japan.The 1-km and 3-km grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region.High-resolution Grid Point Value-Mesoscale Model μgPV-MSM) data were used after suitable validation.The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone.Daily maxima of ozone were found better simulated by the 1-km grid domain than the coarser 9-km and 3-km domains,with the maximum improvement in the mean absolute gross error about 3 ppbv.In addition,1-km grid results fared better than other grids at most of the observation stations that showed noticeable differences in gross error as well as correlation.These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region,such as the Osaka region,which has complex terrain and land-use.  相似文献   
68.
High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with complex terrain and land-use. This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka, Japan. The 1-km and 3-km grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region. High-resolution Grid Point Value-Mesoscale Model (GPV-MSM) data were used after suitable validation. The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone. Daily maxima of ozone were found better simulated by the 1-km grid domain than the coarser 9-km and 3-km domains, with the maximum improvement in the mean absolute gross error about 3 ppbv. In addition, 1-km grid results fared better than other grids at most of the observation stations that showed noticeable di erences in gross error as well as correlation. These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region, such as the Osaka region, which has complex terrain and land-use.  相似文献   
69.
70.
本文对受河南平顶山姚孟热电厂温排水影响的白龟山水库的浮游植物群落的情况进行了野外调查,并在室内对浮游植物的群落结构及其生态学特征进行了模拟增温试验。试验结果表明:水体增温对水库浮游植物的种群组成、优势种的优势度、藻类密度和生物量均有影响。影响的程度与环境固有的水温及增温强度有关。室内增温模拟试验还表明:连续的增温对藻类的光合色素含量和光合作用强度均有影响。   相似文献   
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