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1.
There is a consensus that Marine Protected Area (MPA) performance needs regular evaluation against clear criteria, incorporating counterfactual comparisons of ecological and socio-economic performance. However, these evaluations are scarce at the global level. We compiled self-reports from managers and researchers of 78 coral reef-based MPAs world-wide, on the conservation and welfare improvements that their MPAs provide. We developed a suite of performance measures including fulfilment of design and management criteria, achievement of aims, the cessation of banned or destructive activities, change in threats, and measurable ecological and socio-economic changes in outcomes, which we evaluated with respect to the MPA’s age, geographical location and main aims. The sample was found to be broadly representative of MPAs generally, and suggests that many MPAs do not achieve certain fundamental aims including improvements in coral cover over time (in 25% of MPAs), and conflict reduction (in 25%). However, the large majority demonstrated improvements in terms of slowing coral loss, reducing destructive uses and increasing tourism and local employment, despite many being small, underfunded and facing multiple large scale threats beyond the control of managers. However spatial comparisons suggest that in some regions MPAs are simply mirroring outside changes, with demonstrates the importance of testing for additionality. MPA benefits do not appear to increase linearly over time. In combination with other management efforts and regulations, especially those relating to large scale threat reduction and targeted fisheries and conflict resolution instruments, MPAs are an important tool to achieve coral reef conservation globally. Given greater resources and changes which incorporate best available science, such as larger MPAs and no-take areas, networks and reduced user pressure, it is likely that performance could further be enhanced. Performance evaluation should test for the generation of additional ecological and socio-economic improvements over time and compared to unmanaged areas as part of an adaptive management regime.  相似文献   

2.
Neochetina eichhorniae and N. bruchi. We therefore sampled water hyacinth and weevil populations at 54 sites distributed statewide. Half were under maintenance control, half were not treated with herbicides. General site conditions were assessed, demographic data were collected on weevil and plant populations, the reproductive condition of the weevils was determined, and plant nutrient and proximate composition of water hyacinth leaves were analyzed. Water hyacinth infestations under maintenance control were minimal when compared to unmanaged sites. Likewise, on a population basis, all weevil cohorts were much lower due to the paucity of plants. Plants at unmanaged sites, where weevil intensities were much higher, suffered high levels of stress and showed low growth potential. Lower percentages of the female weevils were reproductive at unmanaged sites when compared to managed sites, so densities of reproductives and immatures were similar at both site types. Reproductive status of the weevils improved with increased plant quality. Plant quality, in turn, declined as stresses arising from weevil feeding increased. Plant quality was positively correlated with plant growth potential and flower production. Thus, maintenance control improved plant nutritive quality thereby inducing reproductive vigor of the weevils, but ensuring plant regrowth and the need for future control. This suggests that biological and herbicidal controls should be integrated, using herbicides to maintain water hyacinth infestations below management thresholds but in a manner that conserves biological control agent populations. This approach would lead to improved plant nutritional quality that would, in turn, stimulate reproduction in biological control agent populations.  相似文献   

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The environmental impacts of bottled water prompted us to explore drinking water choices at Purdue University, located in West Lafayette, IN. A random sample of 2,045 Purdue University students, staff, and faculty was invited to participate in an online survey. The survey assessed current behaviors as well as perceived barriers and benefits to drinking tap water versus bottled water. 677 surveys were completed for a response rate of 33.1%. We then conducted qualitative interviews with a purposive sample of university undergraduates (n = 21) to obtain contextual insights into the survey results and the beliefs of individuals with a variety of drinking water preferences. This study revealed that women drink disproportionately more bottled water then men while undergraduate students drink more than graduate students, staff and faculty. The study also uncovered a widespread belief that recycling eliminates the environmental impacts of bottled water. Important barriers to drinking tap water at Purdue include: perceived risks from tap water and the perceived safety of bottled water, preferring the taste of bottled water, and the convenience of drinking bottled water. The qualitative interviews revealed that drinking water choices can be influenced by several factors—especially whether individuals trust tap water to be clean—but involve varying levels of complexity. The implications of these results for social marketing strategies to promote tap water are discussed.  相似文献   

5.
Varghese, Shalet Korattukudy, Jeroen Buysse, Aymen Frija, Stijn Speelman, and Guido Van Huylenbroeck, 2012. Are Investments in Groundwater Irrigation Profitable? A Case of Rice Farms from South India. Journal of the American Water Resources Association (JAWRA) 1‐15. DOI: 10.1111/j.1752‐1688.2012.00690.x Abstract: This article examines the profitability of cultivating double rice under bore well irrigation, given the cumulative interference of and reduced life span of wells, and thus increases the cost of groundwater extraction and use. The overexploitation of groundwater is a common stock problem and the cultivation of water intensive crops, such as rice, further exacerbates the overdraft of groundwater. Under these circumstances, we quantify the marginal benefit of irrigation investments in rice farming by estimating the probability of having a double rice crop as a function of the investment made in wells. Using this information, we explore profit maximization behavior of farms with a mathematical programming model to derive individual economic optima of irrigation costs. The results demonstrate that the ongoing overexploitation of groundwater, and its use to cultivate an economically inefficient crop, such as rice, has resulted in low profitability at farm level. A sensitivity analysis found that even when the investment in irrigation wells is reduced by 70%, small farms are still not economically efficient, thereby confirming the Tragedy of the Commons. Raising awareness amongst farmers with regard to the economics of irrigation would facilitate the participatory implementation of control mechanisms to regulate groundwater extraction.  相似文献   

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The Sacramento-San Joaquin Delta, the landward reach of the San Francisco Estuary, provides habitat for threatened delta smelt, endangered winter-run Chinook salmon, and other species of concern. It is also the location of huge freshwater diversion facilities that entrain large numbers of fish. Reducing the entrainment of listed fishes into these facilities has required curtailment of pumping, reducing the reliability of water deliveries. We reviewed the first 5 years (2001–2005) of the Environmental Water Account (EWA), a program instituted to resolve conflicts between protecting listed fishes and providing a reliable water supply. The EWA provided fishery agencies with control over 0.2–0.4 km3 of water to be used for fish protection at no cost to users of exported water, and fish agencies guaranteed no disruption of water supply for fish protection. The EWA was successful in reducing uncertainty in water supply; however, its contribution to the recovery of listed fishes was unclear. We estimated the effectiveness of the EWA to be modest, increasing the survival of winter-run Chinook salmon by 0–6% (dependent on prescreen mortality), adult delta smelt by 0–1%, and juvenile delta smelt by 2–4%. Allocating EWA water for a single life stage of one species could provide larger gains in survival. An optimally allocated EWA of equal size to the median of the first 5 years could increase abundance of juvenile delta smelt up to 7% in the springs of dry years. If the EWA is to become a long-term program, estimates of efficacy should be refined. If the program is to be held accountable for quantitative increases in fish populations, it will be necessary to integrate scientific, possibly experimental, approaches.  相似文献   

8.
Rocky intertidal habitats frequently are used by humans for recreational, educational, and subsistence-harvesting purposes, with intertidal populations damaged by visitation activities such as extraction, trampling, and handling. California Marine Managed Areas, particularly regulatory marine reserves (MRs), were established to provide legal protection and enhancement of coastal resources and include prohibitions on harvesting intertidal populations. However, the effectiveness of MRs is unclear as enforcement of no-take laws is weak and no regulations protect intertidal species from other detrimental visitor impacts such as trampling. The goal of this study was two-fold: (1) to determine impacts from human visitation on California mussel populations (Mytilus californianus) and mussel bed community diversity; and (2) to investigate the effectiveness of regulatory MRs in reducing visitor impacts on these populations. Surveys of mussel populations and bed-associated diversity were compared: (1) at sites subjected to either high or low levels of human use, and (2) at sites either unprotected or with regulatory protection banning collecting. At sites subjected to higher levels of human visitation, mussel populations were significantly lower than low-use sites. Comparisons of mussel populations inside and outside of regulatory MRs revealed no consistent pattern suggesting that California no-take regulatory reserves may have limited effectiveness in protecting mussel communities. In areas where many people visit intertidal habitats for purposes other than collecting, many organisms will be affected by trampling, turning of rocks, and handling. In these cases, effective protection of rocky intertidal communities requires an approach that goes beyond the singular focus on collecting to reduce the full suite of impacts.  相似文献   

9.
Government agencies responsible for pest animal management often assume that their views and assumptions about the benefits of control are widely shared, especially if these pests are exotics. This was certainly the case when tens of thousands of feral Asian water buffalo (Bubalus bubalis) were to be culled in Australias Kakadu National Park as part of a national Brucellosis and Tuberculosis Eradication Campaign (BTEC). Implementation of the campaign sparked considerable dispute between officials and aboriginal and non-aboriginal interests about the risks posed by buffalo relative to their value as a potential resource. Drawing upon a variety of written and oral sources relating to the era of buffalo control in Kakadu, this paper critically analyzes the way in which detriment caused by buffalo was appraised and managed under the BTEC program. In particular, the paper focuses the ways in which the BTEC program affected aboriginal people in Kakadu, who view buffalo as a source of customary and economic benefit as well as a source of change on their lands. The paper then considers what lessons can be learned from the BTEC for the development of sensible feral management objectives and strategies. It is argued that effective management of feral animals such as buffalo will require environmental managers to engage with local people and involve them in the definition and management of pest animal damage and methods of control.  相似文献   

10.
To examine ownership and protection status of forests with high-biomass stores (>200 Mg/ha) in the Pacific Northwest (PNW) region of the United States, we used the latest versions of publicly available datasets. Overlay, aggregation, and GIS-based computation of forest area in broad biomass classes in the PNW showed that the National Forests contained the largest area of high-biomass forests (48.4 % of regional total), but the area of high-biomass forest on private lands was important as well (22.8 %). Between 2000 and 2008, the loss of high-biomass forests to fire on the National Forests was 7.6 % (236,000 ha), while the loss of high-biomass forest to logging on private lands (364,000 ha) exceeded the losses to fire across all ownerships. Many remaining high-biomass forest stands are vulnerable to future harvest as only 20 % are strictly protected from logging, while 26 % are not protected at all. The level of protection for high-biomass forests varies by state, for example, 31 % of all high-biomass federal forests in Washington are in high-protection status compared to only 9 % in Oregon. Across the conterminous US, high-biomass forest covers <3 % of all forest land and the PNW region holds 56.8 % of this area or 5.87 million ha. Forests with high-biomass stores are important to document and monitor as they are scarce, often threatened by harvest and development, and their disturbance including timber harvest results in net C losses to the atmosphere that can take a new generation of trees many decades or centuries to offset.  相似文献   

11.
Global marine protection targets have been criticised for being ecologically irrelevant and often inadequate. However, they may also provide motivation for conservation action. However, no such targets have yet been met, and the health of the marine environment has continued to deteriorate. The Tenth Conference of the Parties to the Convention on Biological Diversity (CBD) recently adopted a new marine protection target, in October, 2010. As such, it is timely to critically assess the potential role of this and other global marine protection targets in conservation and marine resource management. Three targets adopted in the past ten years were assessed using the SMART (Specific, Measurable, Achievable, Realistic, and Timebound) framework. This assessment showed that the targets appear to have evolved to have become ‘SMARTer’ over time, particularly more Specific. The most recent CBD target also appears to be more Achievable than earlier targets. Three broad issues emerged that can inform the potential role, limitations, and challenges associated with global-scale marine protection targets: (i) that SMART target formulation, implementation, monitoring, and revision, is critically underpinned by relevant data and information; (ii) that perceived irrelevance of global targets may be at least partly due to a mismatch between the scale at which the targets were intended to operate, and the scale at which they have sometimes been assessed; and (iii) the primary role of global-scale targets may indeed be psychological rather than ecological. Recent progress indicates some success in this role, which could be built on with further ‘SMARTening’ of targets.  相似文献   

12.
Retraction: Olujobi, O.J., & Olusola-Olujobi, T. (2020). Comparative appraisals of legal and institutional framework governing gas flaring in Nigeria's upstream petroleum sector: How satisfactory?. Environmental Quality Management, https://doi.org/10.1002/tqem.21680 The above article from Environmental Quality Management published online on 3 July 2020 in Wiley Online Library ( wileyonlinelibrary.com ) in Early View has been retracted by agreement between the journal Editor in Chief, Jega Jegatheesan and Wiley Periodicals, LLC. The retraction has been agreed due to unattributed overlap with a previously published article from the same group of authors.  相似文献   

13.
/ Since 1975, the European Union (EU) has developed an impressive body of waste management legislation, although, according to the principle of subsidiarity, responsibilities belong to the most local level at which the tasks can be carried out effectively. Using economic theory, this paper examines several factors that influence the efficient distribution of regulatory authority among the EU and the member states. We specifically analyze the role of harmonization that, in our opinion, will often lead to an overcentralization. Within this context, a second issue is becoming more important, as ongoing discussions show. If no consensus can be reached about harmonization, should member states be allowed to stop cross-border shipments of waste, or should the EU strive for a common market for waste? We take the position that most objections against waste shipments are not convincing, especially if the member states implement minimum standards for landfills and waste processing facilities and common information and control systems. Competition between different national regulations within adequate constraints that, e.g., control transboundary externalities leads to more efficient waste management structures in Europe than national self-sufficiency or centralized decision-making at the EU level. KEY WORDS: Waste management; European Union; Subsidiarity; Institutional competition; Harmonization; Cross-border shipments of waste  相似文献   

14.
A relatively under-researched question is whether there is a possibility of influencing environmentally aware tourists regarding ecotourism at destinations that continue to develop under a pattern of mass 'seaside' tourism. Our objective was to assess the pro-environmental intentions of visitors at two small Greek islands, which are within a Natura 2000 site, specifically Paxoi and Antipaxoi. Intentions involved willingness to receive information about the protected area, willingness to accept pro-environmental limitations on recreational experience, and willingness-to-pay a conditional environmental conservation value added tax. In addition, we aimed to identify determinants of visitor pro-environmental intentions among visitor and visit characteristics, visitor satisfaction, and self-reported environmental knowledge, as well as anticipated outcomes of tourism development and suggestions for protected area management. We randomly collected 324 usable questionnaires during the summer season; 242 (74.69?%) by Greek visitors and 82 (25.31?%) by foreign visitors. Visitor satisfaction was quite high; however, visitors reported low levels of environmental knowledge. Our findings showed that the unique characteristics of the destination were not salient among visitors and that there is a lack of effective outreach campaigns, interpretation, and on-site environmental education programs. However, our study revealed high levels of visitor pro-environmental intentions that might support the promotion of ecotourism on the two islands. We provide recommendations based on determinants of visitor pro-environmental intentions, which might assist towards advancing visitor participation in environmental education projects, environmentally responsible behavior among visitors, and financial contribution to environmental conservation by visitors.  相似文献   

15.
In response to the problem of holiday hunger, hundreds of local “holiday clubs” have recently been established across the UK. This research examines the spatial relationship between income, childhood deprivation, ethnicity and holiday clubs across 32,844 Lower Super Output Areas (LSOAs) in England to determine if these clubs are currently operating in an inclusive fashion. Data on the location of holiday clubs comes from a national survey. Binary logistic regression results suggest that holiday clubs are likely to operate in economically disadvantaged areas. At the same time, clubs are not distributed equally by ethnicity. That is, holiday clubs operated by voluntary organisations are more likely to be situated in LSOAs that are disproportionately white and English\British and less likely to be situated in LSOAs that are disproportionately ethnic minority. This finding has important implications for the pursuit of holiday clubs as a policy mechanism for addressing access to food in light of the state’s failure to adequately feed all of the country’s children.  相似文献   

16.
Based on the reasoning that contextual variations are important for understanding differences in forest cognitions, this study examined forest values and management attitudes in the general public in Germany (n = 1135) and Sweden (n = 1311) by means of a questionnaire. Results indicated that the public in both countries emphasised similar forest values, and the overall pattern was comparable for different types of forest, although certain differences based on forest type and country were evident. For example, the German public was more ecologically oriented, whereas the Swedish public was more production oriented in its forest values and management attitudes. Furthermore, ecological and various anthropocentric forest values were perceived to be quite compatible, with the Swedish respondents perceiving this to a greater extent than the German. The overall cognitive structure of forest values and management attitudes was similar in both countries, although differences were revealed, particularly regarding attitudes.  相似文献   

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