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21.
Whereas past research has treated co-management of common pool resources as if villagers and project implementing authorities
were the only relevant actors, numerous external factors beyond the control of these two partners create barriers to successful
co-management. This paper draws on discussions with Forest Department officials to examine the influence of these forces on
the outcomes of Joint Forest Management (JFM) in Tamil Nadu, India. An empirical inquiry into the operational aspects of JFM
indicates the important roles of political parties, powerful people, and other state institutions and functionaries as well
as the flow of foreign funding. Further, the strong demand by local people for socio-economic development interventions as
opposed to improvement of degraded forests belittles the role of the Forest Department relative to other departments. Numerous
other conditioning factors and relationships are explored. The authors call for reforms in public governance to allow better
participation of all the actors involved for this participatory management approach to succeed and sustain. 相似文献
22.
Although stewardship has been widely defined and used in environmental management and planning, there is a dearth of studies
that describe how the lay public perceives this concept. A national sample of residents in 14 states who live near DOE nuclear
facilities were interviewed to delineate public understanding and awareness of the stewardship program of the U.S. Department
of Energy (DOE). This study discusses the findings of the survey and discusses how institutional trust influences public participation
and resident’s choices of potential stewards. Almost 40% of the respondents could not define stewardship; those who did, believed
that ‘responsibility,’ ‘management,’ and ‘accountability’ are key elements of stewardship. In addition, about a third of the
respondents identified Federal groups and the DOE as potential stewards.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue 相似文献
23.
Hiroshi Yamamoto Yudai Nakamura Yuki Nakamura Chise Kitani Tetsuya Imari Jun Sekizawa Yuji Takao Naoyuki Yamashita Narisato Hirai Shigeto Oda Norihisa Tatarazako 《Environmental sciences》2007,14(4):177-193
Eight pharmaceuticals were selected on the basis of their domestic consumption in Japan, the excretion ratio of the parent compound and the frequency of detection in the aquatic environment or wastewater treatment plant effluent. Toxicity tests on these pharmaceuticals were conducted using Japanese medaka (Oryzias latipes), daphnia (Daphnia magna), and green algae (Psuedokirchneriella subcapitata). Predicted no effect concentration (PNEC) was calculated using lethal or effect concentration 50 (LC50 or EC50) values and no effect concentration (NOEC) obtained in the toxicity tests for these compounds. Predicted environmental concentration (PEC) was also calculated from annual consumption, the excretion rate of the parent compound, and removal rate in the preliminary batch activated sludge treatment performed in this study. Maximum concentrations found in the aquatic environment or sewage effluent in Japan or foreign countries were also used for another calculation of PEC. Initial risk assessment on the selected pharmaceuticals was performed using the PEC/PNEC ratio. The results of initial risk assessment on the eight selected pharmaceuticals suggest neither urgent nor severe concern for the ecological risk of these compounds, but further study needs to be conducted using chronic toxicity tests, including reproduction inhibition and endocrine disruption assessments. 相似文献
24.
Environmental factors have long been shown to influence species distributions, with range limits often resulting from environmental
stressors exceeding organism tolerances. However, these abiotic factors may differentially affect species with multiple life-history
stages. Between September 2004 and January 2006, the roles of temperature and nutrient availability in explaining the southern
distributions of two understory kelps, Pterygophora californica and Eisenia arborea (Phaeophyceae, Laminariales), were investigated along the coast of California, USA and the Baja California Peninsula, Mexico,
by limiting either: (a) tissue nitrogen uptake and storage by adult sporophytes during periods of elevated temperature, and/or
(b) production of embryonic sporophytes by microscopic gametophytes. Results suggest that while adult sporophytes of both
species are tolerant of high temperatures and low nutrients, reproduction by their microscopic stages is not. Specifically,
while E. arborea produced embryonic sporophytes at both 12 and 18°C, temperatures commonly observed throughout the southern portion of its
range, P. californica produced sporophytes at 12 but not at 18°C. As a result, it appears that the southern distribution of P. californica, which ends in northern Baja California, Mexico, may be limited by temperature acting on its microscopic stages. In contrast,
the ability of E. arborea’s microscopic and adult stages to tolerate elevated temperatures allows it to persist in the warmer southern waters of Baja
California, as well as to the north along the California coast where both species co-occur. 相似文献
25.
Tone River supplies most of the water requirements of the Tokyo Metropolitan Area (TMA). Lowering of Tone flow and yearly
fluctuation, however, is causing water shortage along TMA nowadays. This study investigated the future water availability
scenarios under climatic changes. A state-of-the-art approach to utilize the output of several GCM has been demonstrated to
investigate the future water availability scenarios for TMA from the Tone River. An integrated modeling approach for water
balance considering several hydrological risk indices was adopted to quantify the future changes in this case. It is observed
that the future summer precipitation along the Tone basin is going to be increased considerably, while an almost constant
or decreasing trend is observed for winter season. Natural flow availability for winter or spring seasons thus can be crucial
under future scenarios. After reservoir routing, the hydrological risk indices estimated, however, were not found to be changed
significantly due to the presence of a robust reservoir system at the upstream. 相似文献
26.
根据环境意识结构.设计了旅游管理部门环境意识调查问卷。其主要的指标体系包括:旅游环境知识水平、旅游环境态度、旅游环境评价和旅游环境行为四个方面。对指标体系各部分之间以及每一指标部分的每一题目之间的相对重要性进行权重的确定.而且对各部分的每道题目的各个选项予以赋分。基于权重和赋分.结合调查问卷的实际情况,设计了指标体系各部分评价模型和环境意识总体评价模型。以此来计算草原旅游发展中旅游管理部门环境意识水平的综合得分。经过分析得知,旅游管理部门环境意识模式是“环境知识制约型”模式。 相似文献
27.
Ricardo Braun 《Environment, Development and Sustainability》2007,9(4):387-411
The implementation of sustainable development may seem a simple concept when written on paper. However to carry-out long term
actions put forward by the Agenda 21 (AG21) at the local level represents one of the main challenges as municipal governments
in general do not have the capacity to effectively implement the process.
Regional environmental assessment (REA) has shown to be effective in supporting decision-making not only to correct environmental
problems due to past unsustainable social-economic developments but also help local governments to implement sustainable actions.
However this requires long-term investments of AG21 plans and projects. The allocation of regular and consistent financial
resources is one of the main ingredients for the sustainable development process. But traditional plans and projects financed
by national and/or international funds may not be sustainable in the long-term because they become dependent on external funding.
Research demonstrate that innovative economic instruments such as ecotaxes represent a feasible alternative to sponsor local
sustainability because taxes are collected permanently by the government and could be invested in continuous actions. Ecotaxes
experiences have provided important reference to structure a municipal incentive model (MIM) to sponsor AG21’s environmental
plans and projects on a long-term (permanent) basis.
However sustainable development cannot be solely through economic investments. A comprehensive municipal environmental management
scheme (MEMS) has been established to support the incentive model. The scheme seeks not only to improve local institutional
framework but also incentive continuous participation of local stakeholders at all levels of society. Participatory events
and the provision of incentives (educational and financial) are key to motivate society to protect the environment and support
actively the sustainable development process as emphasised in the RIO-92 Conference. 相似文献
28.
Lei Jun & Zhang Xiaolei Xinjiang Institute of Ecology Geography Chinese Academy of Sciences Urumqi China Institute of Geography Science Natural Resources Research Chinese Academy of Sciences Beijing .China 《中国人口.资源与环境(英文版)》2005,3(3)
As a special basic economic region in China, Xinjiang is situated in the arid area in the Northwest China. Oasis agriculture is the basis of the national economy. The development of oasis agriculture helps to accelerate the development of economy, social and environment. After 50 years of practice, from 1949 to 2002, oasis agriculture in Xinjiang enhanced rapidly the scale of agricultural industry and had great changes in its structure. The amount of cultivated area rose from 120.97*102 ha t… 相似文献
29.
关中地区飑线天气的预测及灾害对策探讨 总被引:1,自引:0,他引:1
对1961~1990年发生在陕西省关中地区的飑线天气及其灾害进行了统计分析,并从天气形势背景方面对飑线的发生发展进行了研究和分析,同时就飑线的预测和防灾对策进行了探讨。 相似文献
30.
Zhang Yuqing Zhan Chengcheng Wang Hui Gao Ya 《Environment, Development and Sustainability》2022,24(8):9777-9808
Environment, Development and Sustainability - This study analyzes the evolution of the land use structure, demographic reconstruction, and social reconstruction of Dachangshan Island, Changhai... 相似文献