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991.
Rafa Barquin 《国际发展与全球生态学杂志》2013,20(6):513-524
The aim of this paper is to check the hypothesis for the environmental Kuznets curve for sulfur dioxide. This involved analysis of: 1. the theoretical basis of the model; 2. the technical problem of SO2 generation; 3 the kind of information used in the estimations; 4. changes in the structure of electric energy production; 5. improvements in energy efficiency; and 6. the recent introduction of cleaning mechanisms in a favourable political context. The conclusion is that, if it is possible to prove the existence of environmental Kuznets curve models, their utility as instruments of economic policy is debatable. 相似文献
992.
Indicators for Transboundary River Management 总被引:2,自引:0,他引:2
993.
Bruce M. Pavlik 《Environmental management》2001,28(2):243-253
Measurements of xylem water potential, leaf conductance, and leaf pressure–volume characteristics on the geothermal endemic
Dichanthelium lanuginosum var. thermale (DILA) were used to delineate operational ranges during wet and dry years and among several microsites at Little Geysers,
Sonoma County, California, USA. Plants seldom experienced water potentials more negative that −1.5 MPa. Other nongeothermal,
widespread species experienced the lower water potentials typical of chaparral and woodland plants. DILA was able to effectively
utilize geothermal water while the widespread species could not and was able to keep stomata open during most of the year.
There was evidence to suggest that DILA had some ability to acclimate with significant shifts in Πo and ψo during the dry 1994 summer, especially in the upland microhabitat. Nevertheless, minimum leaf turgor values in the upland
came very close to, or dropped below, the 0.2–0.3 MPa threshold thought necessary to maintain stomatal opening and photosynthesis.
DILA thus depends upon the unique water status of fumarole soils in the vicinity of the Little Geysers to persist in an otherwise
lethal regional mosaic of climate, soil, and vegetation. The physiological data were used to derive reference ranges for subsequent
monitoring of DILA at Little Geysers. Such ranges are required to determine the future impact, if any, of geothermal development
on the persistence of this rare grass and its complex ecosystem. 相似文献
994.
The Environmental Impact of Shrimp Aquaculture: Causes, Effects, and Mitigating Alternatives 总被引:3,自引:0,他引:3
FEDERICO PÁEZ-OSUNA 《Environmental management》2001,28(1):131-140
Attracted by the demand for shrimp in the developed countries, shrimp aquaculture has expanded rapidly, mainly in the subtropical
and tropical lowlands of America and Asia. This work provides a global review and viewpoint on the environmental impacts of
shrimp aquaculture, considering the causes and effects of the siting and operation of shrimp ponds and abandonment of farm
facilities. Additionally, mitigating alternatives are discussed. To date, approximately 1–1.5 million ha of coastal lowlands
have been converted into shrimp ponds, comprising mainly salt flats, mangrove areas, marshes, and agricultural lands. The
impact of shrimp farming of most concern is the destruction of mangroves and salt marshes for pond construction. Compatibility
with other users, the presence of buffer zones, maintaining an acceptable balance between mangroves and shrimp pond area,
improved pond design, reduction of water exchange, and an improved residence time of water, size and capacity to assimilate
effluents of the water body, are examples of ways to mitigate the adverse effects. The use of mangroves and halophytes as
biofilters of shrimp pond effluents offers an attractive tool for reducing the impact in those regions where mangrove wetlands
and appropriate conditions for halophyte plantations exist. Healthy seed supply, good feed with the use of prophylactic agents
(including probiotics), good water quality, and lower stocking densities are examples of actions suggested to control disease
in shrimp farming. Finally, in the context of integrated management, research priorities are suggested. 相似文献
995.
XU JIONGXIN 《Environmental management》2001,28(1):101-113
In recent years, the desiccation of the lower Yellow River has raised concerns in the government, public, and scientific community
in China. Long-term and widespread desiccation of rivers is a disaster with many adverse environmental implications. It has
been found in this study that there exists a high-frequency zone of river desiccation disasters at 34°–42°N in the North China
Plain. The hazardous environment is characterized by semiarid climate, widely distributed thick loess in the basin and a “hanging
river bed” in the plain as well as unfavorable man–water–land coupling relationships. In this setting, the sharply increased
water diversion by man since the late 1950s led to the occurrence of river desiccation disasters in the lower reaches of the
river in this area. 相似文献
996.
A Combined Park Management Framework Based on Regulatory and Behavioral Strategies: Use of Visitors' Knowledge to Assess Effectiveness 总被引:1,自引:0,他引:1
KOSTANTINOS PAPAGEORGIOU 《Environmental management》2001,28(1):61-73
In light of the increasing mandate for greater efficiency in conservation of natural reserves such as national parks, the
present study suggests educational approaches as a tool to achieve conservation purposes. Currently, the management of human–wildlife
interactions is dominated by regulatory strategies, but considerable potential exists for environmental education to enhance
knowledge in the short run and to prompt attitude change in the long run. A framework for conservation based on both traditional
regulatory- and behavior-oriented strategies was proposed whereby the level of knowledge that park visitors have acquired
comprises an obvious outcome and establishes a basis upon which the effectiveness of regulatory- and behavior-based regimes
could be assessed. The perceptions regarding park-related issues of two distinct visitor groups (locals and nonlocals) are
summarized from a survey undertaken in Vikos-Aoos national park. The findings suggest a superficial knowledge for certain
concepts but little profound understanding of the content of such concepts, indicating that knowledge-raising efforts should
go a long way towards establishing a positive attitude for the resource. Visitors' poor knowledge of the park's operation
regulation contest the efficiency of the presently dominant regulatory management regime. While geographical distances did
not appear to significantly differentiate knowledge between the two groups, wilderness experience (as certified by visits
to other parks) was proved to be an impetus for generating substantial learner interest in critical park issues among nonlocal
visitors. School education and media were found to be significant knowledge providers. 相似文献
997.
Adaptive management (AM) is the process of implementing land management activities in incremental steps and evaluating whether desired outcomes are being achieved at each step. If conditions deviate substantially from predictions, management activities are adjusted to achieve the desired outcomes. Thus, AM is a kind of monitoring, an activity that land management agencies have done poorly for the most part, at least with respect to ground-based monitoring. Will they do better in the future? We doubt it unless costs, personnel, and future commitment are seriously addressed. Because ecosystem responses to management impacts can ripple into the distant future, monitoring programs that address only the near future (e.g., 10–20 years), are probably unreliable for making statements about resource conditions in the distant future. We give examples of this. Feedback loops between ecosystem response and adjustment of management actions are often broken, and therefore AM again fails. Successful ground-based monitoring must address these and other points that agencies commonly ignore. As part of the solution, publics distrustful of agency activities should be included in any monitoring program. 相似文献
998.
Criteria for Oil Spill Recovery: A Case Study of the Intertidal Community of Prince William Sound, Alaska, Following the Exxon Valdez Oil Spill 总被引:1,自引:0,他引:1
Marine intertidal organisms in Prince William Sound were exposed to crude oil following the T/V Exxon Valdez oil spill in 1989. The intertidal communities were also subjected to mechanical disturbance during invasive oil spill remediation
and cleanup efforts. Using monitoring data collected from 1989 to 1997, impacts and eventual recovery were assessed at oiled
but uncleaned sites and oiled and cleaned study areas. A statistical model where recovery was defined as parallelism between
the time profiles at control and oiled sites was evaluated. Statistical analysis and graphical presentations of the data suggest
intertidal epibiota communities recovered from the oil spill by 1992 at the oiled sites and by 1994 at the oiled and remediated
sites. Empirical data from the intertidal monitoring program supports the use of tests of parallelism in evaluating recovery
and the need to avoid simply the comparison of sample means from control and oiled sites. 相似文献
999.
KEVIN M. BROWN R. MICHAEL ERWIN MILO E. RICHMOND P. A. BUCKLEY JOHN T. TANACREDI DAVE AVRIN 《Environmental management》2001,28(2):207-224
During the 1980s, the exponential growth of laughing gull (Larus atricilla) colonies, from 15 to about 7600 nests in 1990, in the Jamaica Bay Wildlife Refuge and a correlated increase in the bird-strike
rate at nearby John F. Kennedy International Airport (New York City) led to a controversy between wildlife and airport managers
over the elimination of the colonies. In this paper, we review data to evaluate if: (1) the colonies have increased the level
of risk to the flying public; (2) on-colony population control would reduce the presence of gulls, and subsequently bird strikes,
at the airport; and (3) all on-airport management alternatives have been adequately implemented. Since 1979, most (2987, 87%)
of the 3444 bird strikes (number of aircraft struck) were actually bird carcasses found near runways (cause of death unknown
but assumed to be bird strikes by definition). Of the 457 pilot-reported strikes (mean = 23 ± 6 aircraft/yr, N= 20 years), 78 (17%) involved laughing gulls. Since a gull-shooting program was initiated on airport property in 1991, over
50,000 adult laughing gulls have been killed and the number of reported bird strikes involving laughing gulls has declined
from 6.9 ± 2.9 (1983–1990) to 2.6 ± 1.3 (1991–1998) aircraft/yr; nongull reported bird strikes, however, have more than doubled
(6.4 ± 2.6, 1983–1990; 14.9 ± 5.1, 1991–1998). We found no evidence to indicate that on-colony management would yield a reduction
of bird strikes at Kennedy Airport. Dietary and mark–recapture studies suggest that 60%–90% of the laughing gulls collected
on-airport were either failed breeders and/or nonbreeding birds. We argue that the Jamaica Bay laughing gull colonies, the
only ones in New York State, should not be managed at least until all on-airport management alternatives have been properly
implemented and demonstrated to be ineffective at reducing bird strikes, including habitat alterations and increasing the
capability of the bird control unit to eliminate bird flocks on-airport using nonlethal bird dispersal techniques. Because
the gull-shooting program may be resulting in a nonsustainable regional population of laughing gulls (>30% decline), we also
recommend that attempts be made to initiate an experimental colony elsewhere on Long Island to determine if colony relocation
is a feasible management option. 相似文献
1000.
Stakeholder Management for Conservation Projects: A Case Study of Ream National Park, Cambodia1 总被引:2,自引:0,他引:2
THANAKVARO THYL DE LOPEZ 《Environmental management》2001,28(1):47-60
The paper gives an account of the development and implementation of a stakeholder management framework at Ream National Park, Cambodia. Firstly, the concept of stakeholder is reviewed in management and in conservation literatures. Secondly, the context in which the stakeholder framework was implemented is described. Thirdly, a five-step methodological framework is suggested: (1) stakeholder analysis, (2) stakeholder mapping, (3) development of generic strategies and workplan, (4) presentation of the workplan to stakeholders, and (5) implementation of the workplan. This framework classifies stakeholders according to their level of influence on the project and their potential for the conservation of natural resources. In a situation characterized by conflicting claims on natural resources, park authorities were able to successfully develop specific strategies for the management of stakeholders. The conclusion discusses the implications of the Ream experience and the generalization of the framework to other protected areas. 相似文献