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1.
J Environ Manage ; 200: 6-21, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28549304

RESUMO

Wetlands in the region of Southern Ontario, Canada have declined substantially from their historic area. Existing regulations and programs have not abated this decline. However, reversing this trend by protecting or restoring wetlands will increase the supply of important ecosystem services. In particular, these actions will contribute to moderating the impacts of extreme weather predicted to result from climate change as well as reducing phosphorous loads in Lake Erie and ensuing eutrophication. Since the majority of land in the region is privately owned, landowners can play an important role. Thus, we assessed landowner preferences for voluntary incentive-based wetlands conservation programs using separate choice experiments mailed to farm and non-farm landowners in the Grand River and Upper Thames River watersheds. Latent class models were separately estimated for the two data sets. Marginal willingness to accept, compensating surplus, and participation rates were estimated from the resulting models to gain insight into the financial compensation required by landowners and their potential participation. Many of the participating landowners appear willing to participate in wetlands conservation at reasonable cost, with more willing groups notably marked by past participation in incentive-based conservation programs. They generally favor wetlands conservation programs that divert smaller areas of land to wetlands conservation, target marginal agricultural land, use treed buffers to protect wetlands, offer technical help, and pay financial incentives. However, landowners appear reluctant to receive public recognition of their wetland conservation actions. Our results are of interest to natural resource managers designing or refining wetlands conservation programs.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Áreas Alagadas , Ecossistema , Ontário
2.
Environ Manage ; 58(3): 446-64, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27372660

RESUMO

Cultural landscapes in Austria are multifunctional through their simultaneous support of productive, habitat, regulatory, social, and economic functions. This study investigates, if changing climatic conditions in Austria will lead to landscape change. Based on the assumption that farmers are the crucial decision makers when it comes to the implementation of agricultural climate change policies, this study analyzes farmers' decision-making under the consideration of potential future climate change scenarios and risk, varying economic conditions, and different policy regimes through a discrete choice experiment. Results show that if a warming climate will offer new opportunities to increase income, either through expansion of cash crop cultivation or new land use options such as short-term rotation forestry, these opportunities will almost always be seized. Even if high environmental premiums were offered to maintain current cultural landscapes, only 43 % of farmers would prefer the existing grassland cultivation. Therefore, the continuity of characteristic Austrian landscape patterns seems unlikely. In conclusion, despite governmental regulations of and incentives for agriculture, climate change will have significant effects on traditional landscapes. Any opportunities for crop intensification will be embraced, which will ultimately impact ecosystem services, tourism opportunities, and biodiversity.


Assuntos
Agricultura/tendências , Mudança Climática , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Agricultura Florestal/tendências , Formulação de Políticas , Agricultura/economia , Agricultura/métodos , Áustria , Biodiversidade , Ecossistema , Fazendeiros , Previsões , Agricultura Florestal/economia , Agricultura Florestal/métodos , Humanos
3.
Prev Sci ; 13(6): 562-73, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22961005

RESUMO

The development of effective prevention initiatives requires a detailed understanding of the characteristics and needs of the target audience. To properly identify at-risk individuals, it is crucial to clearly delineate risky from acceptable behavior. Whereas health behavior campaigns commonly use single conditions (e.g., lack of condom use) to identify high-risk cohorts, many risk behaviors are more complex and context dependent, rendering a single condition approach inadequate. Out-of-bounds skiing, an activity associated with voluntary exposure to avalanche hazard, is an example of such a multifaceted risk-taking activity. Using a dataset from an extensive online survey on out-of-bounds skiing, we present an innovative approach for identifying at-risk individuals in complex risk environments. Based on a risk management framework, we first examine risk-taking preferences of out-of-bounds skiers with respect to exposure and preparedness--the two main dimensions of risk management--separately. Our approach builds on existing person-centered research and uses Latent Class Analysis to assign survey participants to mutually exclusive behavioral classes on these two dimensions. Discrete Choice Experiments are introduced as a useful method for examining exposure preferences in the context of variable external conditions. The two class designations are then combined using a risk matrix to assign overall risk levels to each survey participant. The present approach complements existing person-centered prevention research on the antecedents of risk-taking by offering a process-oriented method for examining behavioral patterns with respect to the activity itself. Together, the two approaches can offer a much richer perspective for informing the design of effective prevention initiatives.


Assuntos
Avalanche , Segurança , Esqui , Estudos de Coortes , Humanos , Medição de Risco
4.
Conserv Biol ; 25(3): 587-96, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21488955

RESUMO

In the United States, voluntary incentive programs that aid conservation of plant and wildlife species on private lands provide a structural solution to the problem of protecting endangered species by reducing costs and enhancing benefits to landowners. We explored the potential for incentives to encourage landowners to manage land cover for the benefit of endangered songbirds in central Texas (U.S.A.) by asking landowners to indicate their preferences for financial incentives, technical assistance, and regulatory assurances. We identified owners of potential songbird habitat and collected data in face-to-face interviews and self-administered questionnaires. We used a latent-class stated-choice model to identify 3 classes of landowners whose choices varied on the basis of their attitudes and perceived social norms: (1) strong positive attitude, perceived social pressure to participate, and willing to participate with relatively few incentives, (2) weak positive attitude, perceived no social pressure to participate, and required strongest incentives, and (3) negative attitude, perceived social pressure not to enroll, and unwilling to participate regardless of incentive structure. Given this heterogeneity in preferences, conservation incentives may increase management of land cover to benefit endangered species on private lands to some degree; however, exclusive reliance on incentives may be insufficient. Promoting conservation on private lands may be enhanced by integrating incentives into an approach that incorporates other strategies for conservation, including social networks and collaborative processes that reinforce social norms.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Motivação , Aves Canoras , Animais , Ecossistema , Meio Social , Texas
5.
Environ Toxicol Chem ; 27(11): 2368-74, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18522476

RESUMO

The fungicide epoxiconazole (Epox), a triazole, belongs to the group of azole compounds that are extensively used as fungicides in various fruit crops. The frequent use of agricultural lands for wintering by migrating birds can be the source of their increased dietary intake of agricultural pesticides. We investigated whether exposure to Epox causes effects on avian fertility and reproduction, using the Japanese quail (Coturnix coturnix japonica) as a model species for the assessment of reproductive effects of pesticides in wild birds. Epox was administered to adult Japanese quail for three weeks at dietary levels of 10, 50, and 500 ppm, and possible effects on reproduction were investigated. Epox administration resulted in a significantly decreased number of spermatids in the 50- and 500-ppm dose groups. Histopathology showed a reduced number of testicular canaliculi with visible germ cells and a reduction in spermatid number. However, testis weight was not affected up to the highest dose level. No impact was observed on hormone levels, fertility, and reproductive outcome, as laying rate and percentage of fertile eggs were not altered. Likewise, treatment had no influence on the egg or chick parameters evaluated. A time- and dose-related transfer of Epox into the eggs was determined in all treatment groups. We conclude that dietary treatment of Japanese quail with 50 and 500 ppm of the triazole fungicide Epox resulted in a clear impact on the testis. The evaluation of the additional endpoints spermatid count and testicular histology have proven useful and are recommended for future studies on avian reproduction.


Assuntos
Compostos de Epóxi/toxicidade , Fungicidas Industriais/toxicidade , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Triazóis/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Coturnix , Relação Dose-Resposta a Droga , Compostos de Epóxi/farmacocinética , Feminino , Masculino , Tamanho do Órgão/efeitos dos fármacos , Espermatozoides/fisiologia , Testículo/patologia , Triazóis/farmacocinética
6.
Environ Manage ; 40(1): 95-104, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17530330

RESUMO

This article applies a stated preference choice model to assess trade-offs that residents of two squatter settlements in Dhaka, Bangladesh might consider if they were given choices for relocation to flood-free areas. The respondents were asked to choose repeatedly from a set of choice cards, which displayed different configurations of financial incentives for relocation, such as free or inexpensive land, loans or nonrepayable grants, and provisions for temporary or permanent employment opportunities. The survey results indicated that despite extensive experience with flood problems, many residents of Mirpur and Vasantek found that certain configurations of economic incentives were not attractive enough for them to relocate to flood-free areas. At the same time, they would prefer a reduction in the risk of flooding at their current location. The economic incentives that would best assist in increasing voluntary relocation of residents from their current locations included free land, nonrepayable grants (Taka 20,000), and long-term employment opportunities. Further, differences in geographic location (i.e., Mirpur vs. Vasantek), income levels, and membership in neighborhood communities were linked with the tendency of residents to stay at their current location.


Assuntos
Comportamento de Escolha , Desastres , Habitação , Modelos Psicológicos , Adulto , Bangladesh , Cidades , Planejamento em Desastres , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Motivação , Áreas de Pobreza , Migrantes , População Urbana
7.
Environ Manage ; 36(2): 317-27, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15995887

RESUMO

Two visitor-monitoring methods, video monitoring and counts by human observers, were compared in order to identify and evaluate their respective advantages and disadvantages. The analysis considered user numbers, user type (walkers, dog walkers, bicyclists, and joggers) and group size of visitors. Remarkable differences were found between the two methods for user type and use levels. At low use levels, evaluations based on video monitoring resulted in fewer single bicyclists compared to counts by human observers, whereas at high use levels, human observers counted fewer walkers and bikers than video-interpreters. Based on this comparative analysis, we derive recommendations for more effective visitor-monitoring approaches. All data were collected during a visitor-monitoring project in the Danube Floodplains National Park in Austria between 1998 and 1999.


Assuntos
Coleta de Dados/estatística & dados numéricos , Gravação em Vídeo , Animais , Áustria , Ciclismo , Conservação dos Recursos Naturais , Coleta de Dados/métodos , Cães , Humanos , Variações Dependentes do Observador , Corrida , Caminhada
8.
Environ Manage ; 29(3): 324-34, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11830763

RESUMO

Only a few empirical studies on forest aesthetics have adopted a water-based perspective for observers and have investigated the perceived visual quality of forested shorelines. In forested environments with many lakes, such as the boreal forest in the Canadian Shield, individuals have greater exposure to forests from water-based rather than in-stand vantage points. This study employed the psychophysical research direction to explore the relationships between scenic beauty and biophysical characteristics of the forested shorelines in the boreal forests. Two model forms were tested. One model related the variation of shoreline forest aesthetic evaluations of near-vista views (140 m offshore) to a set of forest mensuration data. Tree size, tree mortality, conifer shrubs, tree density, amount of hardwood, and slope explained 60.2% of the variance in scenic beauty between the study sites. A second model was calibrated to test the relationship between an already existing ecosystem vegetation classification system and the aesthetic evaluations of the same forested shorelines. When the ecosystem classification was simplified to eight groups, the model explained 48.5% of variance. These models suggest that the psychophysical approach to studying aesthetics can be applied successfully to near-vista evaluations of scenic beauty. The finding that a forest ecosystem classification system is highly related to scenic beauty suggests that, at least in the boreal forest, managers can reasonably estimate the scenic beauty of forested shoreline environments from an ecosystem classification, with little need for intensive data on these sites.


Assuntos
Conservação dos Recursos Naturais , Estética , Opinião Pública , Árvores , Ecossistema , Humanos , Ontário , Percepção
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