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Agricultural practices constitute both the greatest cause of biodiversity loss and the greatest opportunity for conservation1,2, given the shrinking scope of protected areas in many regions. Recent studies have documented the high levels of biodiversity-across many taxa and biomes-that agricultural landscapes can support over the short term1,3,4. However, little is known about the long-term effects of alternative agricultural practices on ecological communities4,5 Here we document changes in bird communities in intensive-agriculture, diversified-agriculture and natural-forest habitats in 4 regions of Costa Rica over a period of 18 years. Long-term directional shifts in bird communities were evident in intensive- and diversified-agricultural habitats, but were strongest in intensive-agricultural habitats, where the number of endemic and International Union for Conservation of Nature (IUCN) Red List species fell over time. All major guilds, including those involved in pest control, pollination and seed dispersal, were affected. Bird communities in intensive-agricultural habitats proved more susceptible to changes in climate, with hotter and drier periods associated with greater changes in community composition in these settings. These findings demonstrate that diversified agriculture can help to alleviate the long-term loss of biodiversity outside natural protected areas1.
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Agricultura/métodos , Agricultura/estatística & dados numéricos , Biodiversidade , Aves/classificação , Florestas , Animais , Bovinos , Costa Rica , Produtos Agrícolas/provisão & distribuição , Extinção Biológica , Agricultura Florestal/estatística & dados numéricos , Aquecimento Global/estatística & dados numéricos , Controle Biológico de Vetores , Polinização , Dispersão de Sementes , Fatores de TempoRESUMO
While some agricultural landscapes can support wildlife in the short term, it is uncertain how well they can truly sustain wildlife populations. To compare population trends in different production systems, we sampled birds along 48 transects in mature forests, diversified farms, and intensive farms across Costa Rica from 2000 to 2017. To assess how land use influenced population trends in the 349 resident and 80 migratory species with sufficient data, we developed population models. We found, first, that 23% of species were stable in all three land use types, with the rest almost evenly split between increasing and decreasing populations. Second, in forest habitats, a slightly higher fraction was declining: 62% of the 164 species undergoing long-term population changes; nearly half of these declines occurred in forest-affiliated invertivores. Third, in diversified farms, 49% of the 230 species with population changes were declining, with 60% of these declines occurring in agriculture-affiliated species. In contrast, 51% of the species with population changes on diversified farms showed increases, primarily in forest-affiliated invertivores and frugivores. In intensive farms, 153 species showed population changes, also with similar proportions of species increasing (50%) and decreasing (50%). Declines were concentrated in agriculture-affiliated invertivores and forest-affiliated frugivores; increases occurred in many large, omnivorous species. Our findings paint a complex picture but clearly indicate that diversified farming helps sustain populations of diverse, forest-affiliated species. Despite not fully offsetting losses in forest habitats, diversified farming practices help sustain wildlife in a critical time, before possible transformation to nature-positive policies and practices.
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Agricultura , Florestas , Animais , Fazendas , Animais Selvagens , AvesRESUMO
Providing affordable and nutritious food to a growing and increasingly affluent global population requires multifaceted approaches to target supply and demand aspects. On the supply side, expanding irrigation is key to increase future food production, yet associated needs for storing water and implications of providing that water storage, remain unknown. Here, we quantify biophysical potentials for storage-fed sustainable irrigation-irrigation that neither depletes freshwater resources nor expands croplands but requires water to be stored before use-and study implications for food security and infrastructure. We find that water storage is crucial for future food systems because 460 km3/yr of sustainable blue water, enough to grow food for 1.15 billion people, can only be used for irrigation after storage. Even if all identified future dams were to contribute water to irrigation, water stored in dammed reservoirs could only supply 209 ± 50 km3/yr to irrigation and grow food for 631 ± 145 million people. In the face of this gap and the major socioecologic externalities from future dams, our results highlight limits of gray infrastructure for future irrigation and urge to increase irrigation efficiency, change to less water-intensive cropping systems, and deploy alternative storage solutions at scale.
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Agricultura , Abastecimento de Água , Humanos , Água , Água Doce , Abastecimento de Alimentos , Conservação dos Recursos Naturais , Irrigação AgrícolaRESUMO
SignificanceTourism accounts for roughly 10% of global gross domestic product, with nature-based tourism its fastest-growing sector in the past 10 years. Nature-based tourism can theoretically contribute to local and sustainable development by creating attractive livelihoods that support biodiversity conservation, but whether tourists prefer to visit more biodiverse destinations is poorly understood. We examine this question in Costa Rica and find that more biodiverse places tend indeed to attract more tourists, especially where there is infrastructure that makes these places more accessible. Safeguarding terrestrial biodiversity is critical to preserving the substantial economic benefits that countries derive from tourism. Investments in both biodiversity conservation and infrastructure are needed to allow biodiverse countries to rely on tourism for their sustainable development.
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Biodiversidade , Desenvolvimento Econômico , Turismo , Conservação dos Recursos Naturais , Costa Rica , Humanos , RecreaçãoRESUMO
Nature underpins human well-being in critical ways, especially in health. Nature provides pollination of nutritious crops, purification of drinking water, protection from floods, and climate security, among other well-studied health benefits. A crucial, yet challenging, research frontier is clarifying how nature promotes physical activity for its many mental and physical health benefits, particularly in densely populated cities with scarce and dwindling access to nature. Here we frame this frontier by conceptually developing a spatial decision-support tool that shows where, how, and for whom urban nature promotes physical activity, to inform urban greening efforts and broader health assessments. We synthesize what is known, present a model framework, and detail the model steps and data needs that can yield generalizable spatial models and an effective tool for assessing the urban nature-physical activity relationship. Current knowledge supports an initial model that can distinguish broad trends and enrich urban planning, spatial policy, and public health decisions. New, iterative research and application will reveal the importance of different types of urban nature, the different subpopulations who will benefit from it, and nature's potential contribution to creating more equitable, green, livable cities with active inhabitants.
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Planejamento de Cidades , Ecossistema , Exercício Físico , Modelos Teóricos , Saúde Pública , HumanosRESUMO
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.
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Conservação dos Recursos Naturais/economia , Tomada de Decisões , Ecossistema , Modelos Econômicos , Desenvolvimento Sustentável , ChinaRESUMO
Tropical agriculture is a major driver of biodiversity loss, yet it can provide conservation opportunities, especially where protected areas are inadequate. To investigate the long-term biodiversity capacity of agricultural countryside, we quantified bird population trends in Costa Rica by mist netting 57,255 birds of 265 species between 1999 and 2010 in sun coffee plantations, riparian corridors, secondary forests, forest fragments, and primary forest reserves. More bird populations (69) were declining than were stable (39) or increasing (4). Declines were common in resident, insectivorous, and more specialized species. There was no relationship between the species richness of a habitat and its conservation value. High-value forest bird communities were characterized by their distinct species composition and habitat and dietary functional signatures. While 49% of bird species preferred forest to coffee, 39% preferred coffee to forest and 12% used both habitats, indicating that coffee plantations have some conservation value. Coffee plantations, although lacking most of the forest specialists, hosted 185 bird species, had the highest capture rates, and supported increasing numbers of some forest species. Coffee plantations with higher tree cover (7% vs. 13%) had more species with increasing capture rates, twice as many forest specialists, and half as many nonforest species. Costa Rican countryside habitats, especially those with greater tree cover, host many bird species and are critical for connecting bird populations in forest remnants. Diversified agricultural landscapes can enhance the biodiversity capacity of tropical countryside, but, for the long-term persistence of all forest bird species, large (>1,000 ha) protected areas are essential.
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Aves , Conservação dos Recursos Naturais , Ecossistema , Agricultura , Animais , Coffea , Costa Rica , Dinâmica Populacional , Clima TropicalRESUMO
A major challenge in transforming development to inclusive, sustainable pathways is the pervasive and persistent trade-off between provisioning services (e.g., agricultural production) on the one hand and regulating services (e.g., water purification, flood control) and biodiversity conservation on the other. We report on an application of China's new Ecological Development Strategy, now being formally tested and refined for subsequent scaling nationwide, which aims to mitigate and even eliminate these trade-offs. Our focus is the Ecosystem Function Conservation Area of Hainan Island, a rural, tropical region where expansion of rubber plantations has driven extensive loss of natural forest and its vital benefits to people. We explored both the biophysical and the socioeconomic options for achieving simultaneous improvements in product provision, regulating services, biodiversity, and livelihoods. We quantified historic trade-offs between rubber production and vital regulating services, finding that, over the past 20 y (1998-2017), there was a 72.2% increase in rubber plantation area, leading to decreases in soil retention (17.8%), water purification [reduced retention of nitrogen (56.3%) and phosphorus (27.4%)], flood mitigation (21.9%), carbon sequestration (1.7%), and habitat for biodiversity (6.9%). Using scenario analyses, we identified a two-pronged strategy that would significantly reduce these trade-offs, enhancing regulating services and biodiversity, while simultaneously diversifying and increasing product provision and improving livelihoods. This general approach to analyzing product provision, regulating services, biodiversity, and livelihoods has applicability in rural landscapes across China, South and Southeast Asia, and beyond.
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Conservação dos Recursos Naturais , Ecologia , Biodiversidade , China , Ecologia/métodos , Ecologia/organização & administração , Ecossistema , Monitoramento Ambiental , Humanos , Pobreza/prevenção & controleRESUMO
The equilibrium theory of island biogeography is the basis for estimating extinction rates and a pillar of conservation science. The default strategy for conserving biodiversity is the designation of nature reserves, treated as islands in an inhospitable sea of human activity. Despite the profound influence of islands on conservation theory and practice, their mainland analogues, forest fragments in human-dominated landscapes, consistently defy expected biodiversity patterns based on island biogeography theory. Countryside biogeography is an alternative framework, which recognizes that the fate of the world's wildlife will be decided largely by the hospitality of agricultural or countryside ecosystems. Here we directly test these biogeographic theories by comparing a Neotropical countryside ecosystem with a nearby island ecosystem, and show that each supports similar bat biodiversity in fundamentally different ways. The island ecosystem conforms to island biogeographic predictions of bat species loss, in which the water matrix is not habitat. In contrast, the countryside ecosystem has high species richness and evenness across forest reserves and smaller forest fragments. Relative to forest reserves and fragments, deforested countryside habitat supports a less species-rich, yet equally even, bat assemblage. Moreover, the bat assemblage associated with deforested habitat is compositionally novel because of predictable changes in abundances by many species using human-made habitat. Finally, we perform a global meta-analysis of bat biogeographic studies, spanning more than 700 species. It generalizes our findings, showing that separate biogeographic theories for countryside and island ecosystems are necessary. A theory of countryside biogeography is essential to conservation strategy in the agricultural ecosystems that comprise roughly half of the global land surface and are likely to increase even further.
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Agricultura , Biodiversidade , Conservação dos Recursos Naturais , Geografia , Árvores/crescimento & desenvolvimento , Agricultura/métodos , Animais , Quirópteros/fisiologia , Costa Rica , Extinção Biológica , Ilhas , Lagos , Modelos Biológicos , Dinâmica PopulacionalRESUMO
Recent expansion of the scale of human activities poses severe threats to Earth's life-support systems. Increasingly, protected areas (PAs) are expected to serve dual goals: protect biodiversity and secure ecosystem services. We report a nationwide assessment for China, quantifying the provision of threatened species habitat and four key regulating services-water retention, soil retention, sandstorm prevention, and carbon sequestration-in nature reserves (the primary category of PAs in China). We find that China's nature reserves serve moderately well for mammals and birds, but not for other major taxa, nor for these key regulating ecosystem services. China's nature reserves encompass 15.1% of the country's land surface. They capture 17.9% and 16.4% of the entire habitat area for threatened mammals and birds, but only 13.1% for plants, 10.0% for amphibians, and 8.5% for reptiles. Nature reserves encompass only 10.2-12.5% of the source areas for the four key regulating services. They are concentrated in western China, whereas much threatened species' habitat and regulating service source areas occur in eastern provinces. Our analysis illuminates a strategy for greatly strengthening PAs, through creating the first comprehensive national park system of China. This would encompass both nature reserves, in which human activities are highly restricted, and a new category of PAs for ecosystem services, in which human activities not impacting key services are permitted. This could close the gap in a politically feasible way. We also propose a new category of PAs globally, for sustaining the provision of ecosystems services and achieving sustainable development goals.
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Biodiversidade , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Ecossistema , Anfíbios/crescimento & desenvolvimento , Animais , Aves/crescimento & desenvolvimento , China , Espécies em Perigo de Extinção , Geografia , Atividades Humanas , Humanos , Mamíferos/crescimento & desenvolvimento , Desenvolvimento Vegetal , Répteis/crescimento & desenvolvimento , SoloRESUMO
Article impact statement: New collaborations with accounting research can improve conservation impact of ecosystem-based information systems.
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Conservação dos Recursos Naturais , EcossistemaRESUMO
Decision-makers increasingly seek scientific guidance on investing in nature, but biodiversity remains difficult to estimate across diverse landscapes. Here, we develop empirically based models for quantifying biodiversity across space. We focus on agricultural lands in the tropical forest biome, wherein lies the greatest potential to conserve or lose biodiversity. We explore two questions, drawing from empirical research oriented toward pioneering policies in Costa Rica. First, can remotely sensed tree cover serve as a reliable basis for improved estimation of biodiversity, from plots to regions? Second, how does tropical biodiversity change across the land-use gradient from native forest to deforested cropland and pasture? We report on understory plants, nonflying mammals, bats, birds, reptiles, and amphibians. Using data from 67,737 observations of 908 species, we test how tree cover influences biodiversity across space. First, we find that fine-scale mapping of tree cover predicts biodiversity within a taxon-specific radius (of 30-70 m) about a point in the landscape. Second, nearly 50% of the tree cover in our study region is embedded in countryside forest elements, small (typically 0.05-100 ha) clusters or strips of trees on private property. Third, most species use multiple habitat types, including crop fields and pastures (to which 15% of species are restricted), although some taxa depend on forest (57% of species are restricted to forest elements). Our findings are supported by comparisons of 90 studies across Latin America. They provide a basis for a planning tool that guides investments in tropical forest biodiversity similar to those for securing ecosystem services.
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Agricultura/métodos , Biodiversidade , Conservação dos Recursos Naturais , Anfíbios , Animais , Aves , Quirópteros , Costa Rica , Produtos Agrícolas , Ecologia , Florestas , Geografia , Humanos , Mamíferos , Répteis , Especificidade da Espécie , Árvores , Clima TropicalRESUMO
In biophysical terms, humanity has never been moving faster nor further from sustainability than it is now. Our increasing population size and per capita impacts are severely testing the ability of Earth to provide for peoples' most basic needs. Awareness of these circumstances has grown tremendously, as has the sophistication of efforts to address them. But the complexity of the challenge remains daunting. We explore prospects for transformative change in three critical areas of sustainable development: achieving a sustainable population size and securing vital natural capital, both in part through reducing inequity, and strengthening the societal leadership of academia.
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Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/tendências , Ecossistema , Política Ambiental/economia , Política Ambiental/tendências , Liderança , Conservação dos Recursos Naturais/métodos , Humanos , Dinâmica Populacional , Pobreza/estatística & dados numéricos , Fatores SexuaisRESUMO
The most unique feature of Earth is the existence of life, and the most extraordinary feature of life is its diversity. Approximately 9 million types of plants, animals, protists and fungi inhabit the Earth. So, too, do 7 billion people. Two decades ago, at the first Earth Summit, the vast majority of the world's nations declared that human actions were dismantling the Earth's ecosystems, eliminating genes, species and biological traits at an alarming rate. This observation led to the question of how such loss of biological diversity will alter the functioning of ecosystems and their ability to provide society with the goods and services needed to prosper.
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Biodiversidade , Extinção Biológica , Atividades Humanas , Animais , Mudança Climática/estatística & dados numéricos , Consenso , Ecologia/métodos , Ecologia/tendências , HumanosRESUMO
Urbanization has many benefits, but it also is associated with increased levels of mental illness, including depression. It has been suggested that decreased nature experience may help to explain the link between urbanization and mental illness. This suggestion is supported by a growing body of correlational and experimental evidence, which raises a further question: what mechanism(s) link decreased nature experience to the development of mental illness? One such mechanism might be the impact of nature exposure on rumination, a maladaptive pattern of self-referential thought that is associated with heightened risk for depression and other mental illnesses. We show in healthy participants that a brief nature experience, a 90-min walk in a natural setting, decreases both self-reported rumination and neural activity in the subgenual prefrontal cortex (sgPFC), whereas a 90-min walk in an urban setting has no such effects on self-reported rumination or neural activity. In other studies, the sgPFC has been associated with a self-focused behavioral withdrawal linked to rumination in both depressed and healthy individuals. This study reveals a pathway by which nature experience may improve mental well-being and suggests that accessible natural areas within urban contexts may be a critical resource for mental health in our rapidly urbanizing world.
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Córtex Pré-Frontal/fisiologia , Pensamento , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , CaminhadaRESUMO
Diverse motivations for preserving nature both inspire and hinder its conservation. Optimal conservation strategies may differ radically depending on the objective. For example, creating nature reserves may prevent extinctions through protecting severely threatened species, whereas incentivizing farmland hedgerows may benefit people through bolstering pest-eating or pollinating species. Win-win interventions that satisfy multiple objectives are alluring, but can also be elusive. To achieve better outcomes, we developed and implemented a practical typology of nature conservation framed around seven common conservation objectives. Using an intensively studied bird assemblage in southern Costa Rica as a case study, we applied the typology in the context of biodiversity's most pervasive threat: habitat conversion. We found that rural habitats in a varied tropical landscape, comprising small farms, villages, forest fragments, and forest reserves, provided biodiversity-driven processes that benefit people, such as pollination, seed dispersal, and pest consumption. However, species valued for their rarity, endemism, and evolutionary distinctness declined in farmland. Conserving tropical forest on farmland increased species that international tourists value, but not species discussed in Costa Rican newspapers. Despite these observed trade-offs, our analyses also revealed promising synergies. For example, we found that maintaining forest cover surrounding farms in our study region would likely enhance most conservation objectives at minimal expense to others. Overall, our typology provides a framework for resolving the competing objectives of modern conservation.
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Conservação dos Recursos NaturaisRESUMO
Ideally, both ecosystem service and human development policies should improve human well-being through the conservation of ecosystems that provide valuable services. However, program costs and benefits to multiple stakeholders, and how they change through time, are rarely carefully analyzed. We examine one of China's new ecosystem service protection and human development policies: the Relocation and Settlement Program of Southern Shaanxi Province (RSP), which pays households who opt voluntarily to resettle from mountainous areas. The RSP aims to reduce disaster risk, restore important ecosystem services, and improve human well-being. We use household surveys and biophysical data in an integrated economic cost-benefit analysis for multiple stakeholders. We project that the RSP will result in positive net benefits to the municipal government, and to cross-region and global beneficiaries over the long run along with environment improvement, including improved water quality, soil erosion control, and carbon sequestration. However, there are significant short-run relocation costs for local residents so that poor households may have difficulty participating because they lack the resources to pay the initial costs of relocation. Greater subsidies and subsequent supports after relocation are necessary to reduce the payback period of resettled households in the long run. Compensation from downstream beneficiaries for improved water and from carbon trades could be channeled into reducing relocation costs for the poor and sharing the burden of RSP implementation. The effectiveness of the RSP could also be greatly strengthened by early investment in developing human capital and environment-friendly jobs and establishing long-term mechanisms for securing program goals. These challenges and potential solutions pervade ecosystem service efforts globally.
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Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Ecossistema , China , Análise Custo-Benefício , Emigração e Imigração/legislação & jurisprudência , Meio Ambiente , Política Ambiental , Programas Governamentais , HumanosRESUMO
The central challenge of the 21st century is to develop economic, social, and governance systems capable of ending poverty and achieving sustainable levels of population and consumption while securing the life-support systems underpinning current and future human well-being. Essential to meeting this challenge is the incorporation of natural capital and the ecosystem services it provides into decision-making. We explore progress and crucial gaps at this frontier, reflecting upon the 10 y since the Millennium Ecosystem Assessment. We focus on three key dimensions of progress and ongoing challenges: raising awareness of the interdependence of ecosystems and human well-being, advancing the fundamental interdisciplinary science of ecosystem services, and implementing this science in decisions to restore natural capital and use it sustainably. Awareness of human dependence on nature is at an all-time high, the science of ecosystem services is rapidly advancing, and talk of natural capital is now common from governments to corporate boardrooms. However, successful implementation is still in early stages. We explore why ecosystem service information has yet to fundamentally change decision-making and suggest a path forward that emphasizes: (i) developing solid evidence linking decisions to impacts on natural capital and ecosystem services, and then to human well-being; (ii) working closely with leaders in government, business, and civil society to develop the knowledge, tools, and practices necessary to integrate natural capital and ecosystem services into everyday decision-making; and (iii) reforming institutions to change policy and practices to better align private short-term goals with societal long-term goals.