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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.
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
24.
John F. Potter 《The Environmentalist》2006,26(4):329-329
25.
26.
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
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.
In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of prenatal diagnosis. Each bibliography is divided into 17 sections: 1 Books, Reviews & Symposia; 2 General Interest; 3 Normal Fetal Development; 4 Gametogenesis and Pre-implantation Diagnosis; 5 First Trimester Diagnosis; 6 Second Trimester Diagnosis; 7 Fetal Diagnosis by Ultrasound and Other Imaging; 8 Maternal Screening; 9 Screening for Carriers of Genetic Abnormality; 10 Technological Developments; 11 Confined Placental Mosaicism and Uniparental Disomy; 12 Molecular Cytogenetics; 13 Fetal Cells in Maternal Circulation; 14 Fetal Therapy; 15 Psychosocial Aspects; 16 Epidemiology and Environmental Factors; 17 Developmental Pathology. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted 相似文献
29.
Summary
Ips duplicatus withI. typographus co-inhabiting Norway spruce (Picea abies (L.) Karst.) would benefit from a pheromone blend distinct from that of the larger competitorI. typographus. GC-MS analysis showed thatI. duplicatus males feeding in the host produced ipsdienol (Id),cis-verbenol (cV),trans-verbenol (tV), myrtenol (Mt), andE-myrcenol (EM) and traces of 2-methyl-3-buten-2-ol (MB).I. duplicatus produced Id in approximately racemic form (48.9-54.5% (+)-(S)-isomer). The amounts of Id and EM released over a 9 day period had a maximum of 250 and 5 ng/h/male, respectively, on day 2. Exposure ofI. duplicatus males to myrcene and -pinene resulted in the production of small amounts of Id, cV, tV, Mt, andtrans-pinocarveol, but not of EM. In laboratory bioassays with walking beetles, the pheromone component Id alone was weakly attractive while EM was inactive, but in binary combination with Id strongly synergized attraction. A combination of EM and Id at a release rate equivalent to 100–200 males was more attractive in the field than 70 unmated males in a spruce log. The addition of myrcene ( a suggested pheromone precursor of Id) to Id did not enhance trap caches, while addition of EM increased catches > 10-fold. Subtracting EM from a blend of Id, EM, cV and MB drastically reduced trap catches while subtraction of cV or MB or both had no significant effect. Addition of EM over a wide concentration range to the synthetic pheromone ofI. typographus did not reduce the attraction of females of this species in the laboratory. A two-species pheromone interaction field test releasingI. typographus pheromone components (MB + cV) at 10–1000 male equivalents (ME) andI. duplicatus pheromone (Id + EM) at 0, 10–1000 ME in all possible combinations showed both positive intraspecific dose-response effects and an interspecific inhibition. Higher release rates of EM appeared to inhibitI. typographus, especially males. In a tree colonization model, the response of the two competing species to their respective pheromones show a good separation during the mass-attack with a small initial cross-attraction. It remains to be shown whether either of the two pheromone systems have in fact evolved in the present sympatry, or if they are an incidental effect of ancestry of these phylogenetically distantIps. 相似文献
30.
Chris J. Matthews David B. Newton Roger D. Braddock Bofu Yu 《Environmental Modeling and Assessment》2007,12(1):27-41
Recently, the New Morris Method has been presented as an effective sensitivity analysis tool for mathematical models. The
New Morris Method estimates the sensitivity of an output parameter to a given set of input parameters (first-order effects)
and the extent these parameters interact with each other (second-order effects). This method requires the specification of
two parameters (runs and resolution) that control the sampling of the output parameter to determine its sensitivity to various
inputs. The criteria for these parameters have been set on the analysis of a well-behaved analytical function (see Cropp and
Braddock, Reliab. Eng. Syst. Saf. 78:77–83, 2002), which may not be applicable to other physical models that describe complex
processes. This paper will investigate the appropriateness of the criteria from (Cropp and Braddock, 2002) and hence the effectiveness
of the New Morris Method to determine the sensitivity behaviour of two hydrologic models: the Soil Erosion and Deposition
System and Griffith University Representation of Urban Hydrology. In the first case, this paper will separately analyse the
sensitivity of an output parameter on a set of input parameters (first- and second-order effects) for each model and discuss
the physical meaning of these sensitivities. This will be followed by an investigation into the sampling criteria by exploring
the convergence of the sensitivity behaviour for each model as the sampling of the parameter space is increased. By comparing
these trends to the convergence behaviour from Cropp and Braddock (2002), we will determine how well the New Morris Method
estimates the sensitivity for each model and whether the sampling criteria are appropriate for these models. It will be shown
that the New Morris Method can provide additional insight into the functioning of these models, and that, under a different
metric, the sensitivity behaviour of these models does converge confirming the sampling criteria set by Cropp and Braddock. 相似文献