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2.
PLoS One ; 15(10): e0226397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33001977

RESUMO

State fish and wildlife agencies rely on hunters and anglers (i.e., sportspersons) to fund management actions through revenue generated from license sales and excise taxes on hunting and fishing equipment. There is a need to develop new techniques that bridge the information gap on participation and provide agencies with an understanding of sportspersons at a resolution that can more directly inform efforts to engage sportspersons. Monitoring sportsperson participation using information about their license-purchasing behavior has the potential to reveal important patterns in recruitment (first-time purchase of a hunting or fishing license), retention (continued purchase of licenses across multiple years), and reactivation (purchase a license after several years with no purchases). Providing up-to-date information on what licenses are purchased, when and by whom may prove invaluable to managers and policy makers. We present a customizable, open-source, web-based application-huntfishapp-that allows the user to query and interact with a structured query language (SQL) hunting and fishing license database. The huntfishapp serves as an informational resource and tool that provides a framework to share information on license sales across an agency, with intent of increasing understanding of (a) sportspersons and (b) how management decisions affect sportspersons. Data dashboards, like the huntfishapp, allow agencies and non-governmental organizations to become more knowledgeable of their customer base and provide a greater understanding of management-decision effects on hunting and fishing participation.


Assuntos
Comportamento do Consumidor/economia , Licenciamento , Software , Comércio , Conservação dos Recursos Naturais/economia , Pesqueiros/economia , Humanos , Recreação/economia
6.
PLoS One ; 15(8): e0237425, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785268

RESUMO

Both costs and benefits must be considered when implementing marine protected areas (MPAs), particularly those associated with fishing effort displaced by potential closures. The Southern Ocean offers a case study in understanding such tradeoffs, where MPAs are actively being discussed to achieve a range of protection and sustainable use objectives. Here, we evaluated the possible impacts of two MPA scenarios on the Antarctic krill (Euphausia superba) fishery and krill-dependent predators in the Scotia Sea, explicitly addressing the displacement of fishing from closed areas. For both scenarios, we employed a minimally realistic, spatially explicit ecosystem model and considered three alternative redistributions of displaced fishing. We projected both MPAs to provide positive outcomes for many krill-dependent predators, especially when closed areas included at least 50-75% of their foraging distributions. Further, differences between the scenarios suggest ways to improve seal and penguin protection in the Scotia Sea. MPA scenarios also projected increases in total fishery yields, but alongside risks of fishing in areas where relatively low krill densities could cause the fishery to suspend operations. The three alternatives for redistributing displaced fishing had little effect on benefits to predators, but did matter for the fishery, with greater differences in overall catch and risk of fishing in areas of low krill density when displaced fishing was redistributed evenly among the open areas. Collectively, results suggest a well-designed MPA in the Scotia Sea may protect krill-dependent predators, even with displaced fishing, and preclude further spatial management of the krill fishery outside the MPA. More broadly, outcomes denote the importance of delineating fishing and predator habitat, spatial scales, and the critical trade-offs inherent in MPA development.


Assuntos
Conservação dos Recursos Naturais/economia , Custos e Análise de Custo , Oceanos e Mares , Animais , Euphausiacea/crescimento & desenvolvimento , Modelos Teóricos , Análise Espacial
7.
PLoS One ; 15(8): e0236354, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32750058

RESUMO

With the rising environmental concerns among consumers all over the world, sustainability has received considerable attention, and numerous enterprises are adopting various practices such as investing in energy-saving to improve sustainability in supply chains. However, many previous researches always assume that decision makers are perfectly rational and neglect the behavioral concerns of decision makers. This paper considers a two-stage sustainable supply chain with behavioral concerns in order to develop more realistic models, and mainly focuses on the energy-saving and pricing decisions in the decentralized system, as well as how to improve energy-saving level and profits. We develop decentralized decision-making models under two types of behavioral concerns: fairness concern and risk aversion, and derive the optimal strategy for each member with a Stackelberg game in which the manufacturer acts as the leader. The effect of the behavioral concerns on the optimal decisions and corresponding profits is discussed in detail. Theoretical analysis verified by numerical experiments shows that the fairness behavior always causes a negative effect on the manufacturer, total supply chain, and energy conservation, while it could benefit the retailer in profits. The risk aversion behavior always benefits the manufacturer, total supply chain, and energy conservation, whereas it could make the retailer suffer. Note that both the optimal energy-saving level and corresponding profit of the total supply chain under two types of behavioral concerns are lower than that in the centralized system, thereby we propose a revenue-cost-sharing contract to coordinate the supply chain, under which both the manufacturer and the retailer can achieve a win-win outcome and the energy-saving level can be improved. In addition, some managerial implications through our analytical and numerical results are summarized in this paper.


Assuntos
Comércio/economia , Conservação de Recursos Energéticos/economia , Conservação dos Recursos Naturais/economia , Custos e Análise de Custo/economia , Comportamento do Consumidor/economia , Tomada de Decisões , Teoria do Jogo , Humanos , Assunção de Riscos
8.
PLoS One ; 15(8): e0236958, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760117

RESUMO

Renewable electricity can fully decarbonise the European electricity supply, but large land requirements may cause land-use conflicts. Using a dynamic model that captures renewable fluctuations, I explore the relationship between land requirements and total system cost of different supply-side options in the future. Cost-minimal fully renewable electricity requires some 97,000 km2 (2% of total) land for solar and wind power installations, roughly the size of Portugal, and includes large shares of onshore wind. Replacing onshore wind with offshore wind, utility-scale PV, or rooftop PV reduces land requirements drastically with only small cost penalties. Moving wind power offshore is most cost-effective and reduces land requirements by 50% for a cost penalty of only 5%. Wind power can alternatively be replaced by photovoltaics, leading to a cost penalty of 10% for the same effect. My research shows that fully renewable electricity supply can be designed with very different physical appearances and impacts on landscapes and the population, but at similar cost.


Assuntos
Eletricidade , Energia Renovável , Conservação de Recursos Energéticos/economia , Conservação dos Recursos Naturais/economia , Análise Custo-Benefício , Custos e Análise de Custo , Europa (Continente) , Modelos Teóricos , Recursos Naturais , Centrais Elétricas/economia , Energia Renovável/economia , Energia Solar/economia , Processos Estocásticos , Vento
9.
Proc Natl Acad Sci U S A ; 117(36): 21994-22001, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32839306

RESUMO

Soil erosion is a major global soil degradation threat to land, freshwater, and oceans. Wind and water are the major drivers, with water erosion over land being the focus of this work; excluding gullying and river bank erosion. Improving knowledge of the probable future rates of soil erosion, accelerated by human activity, is important both for policy makers engaged in land use decision-making and for earth-system modelers seeking to reduce uncertainty on global predictions. Here we predict future rates of erosion by modeling change in potential global soil erosion by water using three alternative (2.6, 4.5, and 8.5) Shared Socioeconomic Pathway and Representative Concentration Pathway (SSP-RCP) scenarios. Global predictions rely on a high spatial resolution Revised Universal Soil Loss Equation (RUSLE)-based semiempirical modeling approach (GloSEM). The baseline model (2015) predicts global potential soil erosion rates of [Formula: see text] Pg yr-1, with current conservation agriculture (CA) practices estimated to reduce this by ∼5%. Our future scenarios suggest that socioeconomic developments impacting land use will either decrease (SSP1-RCP2.6-10%) or increase (SSP2-RCP4.5 +2%, SSP5-RCP8.5 +10%) water erosion by 2070. Climate projections, for all global dynamics scenarios, indicate a trend, moving toward a more vigorous hydrological cycle, which could increase global water erosion (+30 to +66%). Accepting some degrees of uncertainty, our findings provide insights into how possible future socioeconomic development will affect soil erosion by water using a globally consistent approach. This preliminary evidence seeks to inform efforts such as those of the United Nations to assess global soil erosion and inform decision makers developing national strategies for soil conservation.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Deslizamentos de Terra/estatística & dados numéricos , Água/química , Mudança Climática/economia , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/tendências , Monitoramento Ambiental , Atividades Humanas , Humanos , Deslizamentos de Terra/economia , Fatores Socioeconômicos , Solo/química
10.
Proc Natl Acad Sci U S A ; 117(36): 21985-21993, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32839335

RESUMO

Major environmental functions and human needs critically depend on water. In regions of the world affected by water scarcity economic activities can be constrained by water availability, leading to competition both among sectors and between human uses and environmental needs. While the commodification of water remains a contentious political issue, the valuation of this natural resource is sometime viewed as a strategy to avoid water waste. Likewise, water markets have been invoked as a mechanism to allocate water to economically most efficient uses. The value of water, however, remains difficult to estimate because water markets and market prices exist only in few regions of the world. Despite numerous attempts at estimating the value of water in the absence of markets (i.e., the "shadow price"), a global spatially explicit assessment of the value of water in agriculture is still missing. Here we propose a data-parsimonious biophysical framework to determine the value generated by water in irrigated agriculture and highlight its global spatiotemporal patterns. We find that in much of the world the actual crop distribution does not maximize agricultural water value.


Assuntos
Irrigação Agrícola/economia , Água/metabolismo , Conservação dos Recursos Naturais/economia , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Abastecimento de Água/economia
12.
Proc Natl Acad Sci U S A ; 117(25): 14593-14601, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513694

RESUMO

Gross domestic product (GDP) summarizes a vast amount of economic information in a single monetary metric that is widely used by decision makers around the world. However, GDP fails to capture fully the contributions of nature to economic activity and human well-being. To address this critical omission, we develop a measure of gross ecosystem product (GEP) that summarizes the value of ecosystem services in a single monetary metric. We illustrate the measurement of GEP through an application to the Chinese province of Qinghai, showing that the approach is tractable using available data. Known as the "water tower of Asia," Qinghai is the source of the Mekong, Yangtze, and Yellow Rivers, and indeed, we find that water-related ecosystem services make up nearly two-thirds of the value of GEP for Qinghai. Importantly most of these benefits accrue downstream. In Qinghai, GEP was greater than GDP in 2000 and three-fourths as large as GDP in 2015 as its market economy grew. Large-scale investment in restoration resulted in improvements in the flows of ecosystem services measured in GEP (127.5%) over this period. Going forward, China is using GEP in decision making in multiple ways, as part of a transformation to inclusive, green growth. This includes investing in conservation of ecosystem assets to secure provision of ecosystem services through transregional compensation payments.


Assuntos
Conservação dos Recursos Naturais/economia , Tomada de Decisões , Ecossistema , Modelos Econômicos , Desenvolvimento Sustentável , China
13.
Proc Natl Acad Sci U S A ; 117(25): 14094-14101, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32522883

RESUMO

Global efforts for biodiversity protection and land use-based greenhouse gas mitigation call for increases in the effectiveness and efficiency of environmental conservation. Incentive-based policy instruments are key tools for meeting these goals, yet their effectiveness might be undermined by such factors as social norms regarding whether payments are considered fair. We investigated the causal link between equity and conservation effort with a randomized real-effort experiment in forest conservation with 443 land users near a tropical forest national park in the Vietnamese Central Annamites, a global biodiversity hotspot. The experiment introduced unjustified payment inequality based on luck, in contradiction of local fairness norms that were measured through responses to vignettes. Payment inequality was perceived as less fair than payment equality. In agreement with our preregistered hypotheses, participants who were disadvantaged by unequal payments exerted significantly less conservation effort than other participants receiving the same payment under an equal distribution. No effect was observed for participants advantaged by inequality. Thus, equity effects on effort can have consequences for the effectiveness and efficiency of incentive-based conservation instruments. Furthermore, we show that women exerted substantially more conservation effort than men, and that increasing payment size unexpectedly reduced effort. This emphasizes the need to consider social comparisons, local equity norms, and gender in environmental policies using monetary incentives to motivate behavioral change.


Assuntos
Conservação dos Recursos Naturais/economia , Renda , Economia Comportamental , Humanos , Psicologia Social/economia
14.
PLoS One ; 15(6): e0234327, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32516354

RESUMO

Massive declines in insect biodiversity and biomass are reported from many regions and habitats. In urban areas, creation of native wildflower meadows is one option to support insects and reduce maintenance costs of urban green spaces. However, benefits for insect conservation may depend on previous land use, and the size and location of new wildflower meadows. We show effects of conversion of roadside plantings-from exotic shrubs into wildflower meadows-on (1) the abundance of 13 arthropod taxa-Opiliones, Araneae, Isopoda, Collembola, Orthoptera, Aphidoidea, Auchenorrhyncha, Heteroptera, Coleoptera, Nematocera, Brachycera, Apocrita, Formicidae-and (2) changes in maintenance costs. We assessed the influence of vegetation type (meadow vs. woody), meadow age, size, location (distance to city boundary), and mowing regime. We found many, but not all, arthropod taxa profiting from meadows in terms of arthropod activity abundance in pitfall traps and arthropod density in standardized suction samples. Arthropod number in meadows was 212% higher in pitfall traps and 260% higher in suction samples compared to woody vegetation. The increased arthropod number in meadows was independent of the size and isolation of green spaces for most taxa. However, mowing regime strongly affected several arthropod taxa, with an increase of 63% of total arthropod density in unmown compared to mown meadow spots. Costs of green space maintenance were fivefold lower for meadows than for woody vegetation. Our study shows that (1) many different arthropod taxa occur in roadside vegetation in urban areas, (2) replacement of exotic woody vegetation by native wildflower meadows can significantly increase arthropod abundance, especially if meadow management permits temporarily unmown areas, and (3) maintenance costs can be considerably reduced by converting woody plantings into wildflower meadows. Considering many groups of arthropods, our study provides new insights into possible measures to support arthropods in urban environments.


Assuntos
Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Insetos/metabolismo , Animais , Biodiversidade , Biomassa , Cidades , Ecossistema , Meio Ambiente , Espécies Introduzidas/economia , Magnoliopsida/crescimento & desenvolvimento , Plantas , Solo , Microbiologia do Solo
17.
PLoS One ; 15(5): e0233339, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428006

RESUMO

Spatial conservation prioritization is used worldwide for designing marine protected areas (MPA) that achieve set conservation objectives with minimal impacts to marine users. People involved in small-scale fisheries (SSF) may incur negative and disproportionate impacts from implementing MPAs, yet limited available data often restricts their representation in MPA planning. Using a Philippines case study, we focus here on the systematic design of a MPA network that aims to minimize and distribute costs equitably for SSF whilst achieving representation targets for biodiversity conservation. The objectives of the study are to: (1) document a participatory mapping approach for collecting SSF data for prioritization using the local knowledge of fishers; and (2) examine how the completeness and resolution of SSF data may affect prioritization outputs in terms of biodiversity representation, spatial efficiency, and distribution equity. In the data-poor region, we conducted participatory mapping workshops with fishers in 79 communities to collect data on the spatial distribution patterns of different SSF fisheries and communities, and employed remote sensing techniques to define coastal habitats, which were targeted for inclusion in MPAs. The datasets were integrated within the decision-support tool Marxan with Zones to develop three scenarios. The SSF data incorporated in each scenario varied based on their completeness (considered all fishing methods or only dominant methods) and resolution (fishing methods itemized by community or municipality). All scenarios derived MPA plans that met representation targets with similar area coverage. The outputs, however, varied in terms of distribution equity, measured by the distribution of opportunity costs (loss of fishing grounds) across different fisheries and communities. Scenarios that did not include minority fisheries or variations between communities, led to inequitable costs. These results highlight the need to incorporate detailed data on SSF at appropriate resolutions, and how this can be achieved through participatory approaches.


Assuntos
Aquicultura/métodos , Conservação dos Recursos Naturais/métodos , Pesqueiros/economia , Aquicultura/economia , Biodiversidade , Conservação dos Recursos Naturais/economia , Coleta de Dados , Ecossistema , Pesqueiros/tendências , Oceanos e Mares/epidemiologia , Filipinas , Dinâmica Populacional , Telemetria
18.
PLoS One ; 15(5): e0230494, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437445

RESUMO

The mobile nature of fishing activity entails dynamic spatial relations and dependencies between coastal communities and fishing grounds drawn by the movement of fishing vessels. Analysing these spatial relations is essential to allocate the socio-economic impact of the fishing activity into the relevant coastal communities. In addition, such spatial information gives the possibility, on the one hand, to assess the impacts from fisheries on the marine environment and, on the other, to manage competing uses of the sea space between different activities. In this paper, we use AIS data, which is individual vessels' positioning data, to examine the activity of the EU large-scale fishing fleets, their home ports, high intensity fishing areas (i.e., main fishing grounds), main ports and coastal communities involved.


Assuntos
Conservação dos Recursos Naturais/economia , Pesqueiros/economia , Mapeamento Geográfico , Navios/economia , Instalações de Transporte , Europa (Continente)
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