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Rapid growth in marine sand mining for construction and other uses poses environmental challenges to coastal nations virtually
worldwide. Yet the development of management policies, such as a system of fees imposed on operators for damage caused by
mining, has been frustrated by a lack of studies to support such measures. Adapting a Beverton-Holt bioeconomic model, this
paper attempts to contribute to the estimation of external costs to commercial fisheries due to marine mining. Using the major
mining area of Ongjin in Korea as a case study, we estimate economic losses in use value of commercial fisheries through the
time to recovery of the injured resource stocks. Present value of lost catch over a 1-year period from mining to resource
recovery is estimated at $38,851 for a single “prototype” mining site. Estimated cumulative damages due to recurring mining
for 5 and 10 years are $1.5 million and $2.2 million, respectively, at 20 mining sites. Sensitivity analyses are used to examine
the effects of alternative assumptions to assess the many sources of uncertainty. Using a form of meta-analysis, dose-response
information is used to assess the excess mortality the mining sediment plume has on eggs and larvae and, ultimately, on the
value of lost catch ($841). Also addressed is the importance of specifying the appropriate “premining” conditions against
which to assess environmental losses at the mining site. Damages estimated with premining fish populations are $23,066 higher
than is the case using postmining conditions. Overall, the illustrative results suggest the variety of complex conditions
which influence damage to fisheries from mining and which can benefit from further study to improve management guidelines.
An erratum to this article can be found at 相似文献
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Effective recreation resource management relies on understanding visitor perceptions and behaviors. Given current and increasing
pressures on water resources, understanding crowding evaluations seems important. Beyond crowding, however, variables that
possibly relate to or influence crowding are of interest and in particular, place attachment and experience-use history (EUH).
As EUH is related to place attachment and likely affects crowding, this study explored the moderating effect of place attachment
dimensions on the relationships between EUH and visitor crowding evaluations. Water based recreationists at a U.S. Army Corps
of Engineers site were contacted onsite and asked questions related to experience-use history, crowding evaluations, place
attachment, and activity participation. Anglers and campers at the site identified similar crowding perceptions and place
attachments. Only one of eight models tested revealed a moderating effect. Specifically, place identity moderated the relationship
between the total times visited in the past twelve months and expected crowding among anglers. As such, the quest continues
to understand the relationship among these important variables. 相似文献
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Suburban Areas in Developing Countries and Their Relationship to Groundwater Pollution: A Case Study of Mar del Plata, Argentina 总被引:1,自引:0,他引:1
Hector E. Massone Daniel E. Martinez Jose L. Cionchi Emilia Bocanegra 《Environmental management》1998,22(2):245-254
2 were sampled in order to verify the impact of these problems on groundwater. All samples were analyzed for major ions, and
about 30 of them for fecal coliforms and heavy metals. Nineteen samples were selected for pesticide analyses. The average
nitrate content was 80 mg/liter, eight times the regional background value. Fecal coliforms were detected in 60% of the analyzed
samples. Zinc content and a high Cl−/HCO3
− ratio were observed in the surroundings of the solid waste disposal area. Moreover, lindane and heptachlor pesticides were
detected in ten samples. 相似文献
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A Conflict-Resolution Model for the Conjunctive Use of Surface and Groundwater Resources that Considers Water-Quality Issues: A Case Study 总被引:6,自引:0,他引:6
The conjunctive use of surface and groundwater resources is one alternative for optimal use of available water resources in
arid and semiarid regions. The optimization models proposed for conjunctive water allocation are often complicated, nonlinear,
and computationally intensive, especially when different stakeholders are involved that have conflicting interests. In this
article, a new conflict-resolution methodology developed for the conjunctive use of surface and groundwater resources using
Nondominated Sorting Genetic Algorithm II (NSGA-II) and Young Conflict-Resolution Theory (YCRT) is presented. The proposed
model is applied to the Tehran aquifer in the Tehran metropolitan area of Iran. Stakeholders in the study area have conflicting
interests related to water supply with acceptable quality, pumping costs, groundwater quality, and groundwater table fluctuations.
In the proposed methodology, MODFLOW and MT3D groundwater quantity and quality simulation models are linked with the NSGA-II
optimization model to develop Pareto fronts among the objectives. The best solutions on the Pareto fronts are then selected
using YCRT. The results of the proposed model show the significance of applying an integrated conflict-resolution approach
to conjunctive use of surface and groundwater resources in the study area. 相似文献
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Environmental Management - Taking 109 gymnosperm species in China as a case, the uncertainty and risk of losing habitat areas of gymnosperm species under future climate conditions were investigated... 相似文献
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The Carolinian Life Zone in southwestern Ontario, Canada is valued because it represents an almost disjunct ecosystem (i.e.,
one that is typical of the mid-Atlantic United States, rather than the rest of Canada or the nearby states in the United States).
The landscape of the Carolinian Life Zone has undergone dramatic transformation, especially in recent decades as agriculture,
urbanization, and recreation have intensified. One of the most apparent changes is the invasion of exotic plant species that
exacerbates the need for mass restoration efforts. Within the Carolinian Life Zone, Rondeau Provincial Park has experienced
an influx of nonindigenous, invasive species in recent years. Tree-of-heaven (Ailanthus altissima) is one example. The infestation is still relatively localized to (mainly) the park, slowly spreading, and manageable as long
as something is done immediately. We examined the effects of hand-pulling and mulching, cut stump and glyphosate application,
cut stump alone, and the EZJect Capsule Injection System (using glyphosate) on the management of A. altissima within the park. Cut stump and glyphosate treatment was most effective and efficient in its control of young A. altissima shoots because it limits disturbance and has acceptable capital and operating costs. Hand-pulling and mulching was the second
choice, mainly because of the risk of additional disturbance that increased shoot densities 1 year after treatment. Cut stump
alone was not effective, worsened the infestation, and is not recommended for this species. The EZJect system was effective
at managing mature, seed-producing shoots, although the somewhat higher capital costs mean that the system probably should
be purchased for management of several invasive tree species to make it more cost-effective. 相似文献