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1.
PLoS Biol ; 17(12): e3000598, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31841524

RESUMO

[This corrects the article DOI: 10.1371/journal.pbio.3000158.].

2.
Sci Adv ; 5(10): eaax2546, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31692892

RESUMO

Intact tropical forests, free from substantial anthropogenic influence, store and sequester large amounts of atmospheric carbon but are currently neglected in international climate policy. We show that between 2000 and 2013, direct clearance of intact tropical forest areas accounted for 3.2% of gross carbon emissions from all deforestation across the pantropics. However, full carbon accounting requires the consideration of forgone carbon sequestration, selective logging, edge effects, and defaunation. When these factors were considered, the net carbon impact resulting from intact tropical forest loss between 2000 and 2013 increased by a factor of 6 (626%), from 0.34 (0.37 to 0.21) to 2.12 (2.85 to 1.00) petagrams of carbon (equivalent to approximately 2 years of global land use change emissions). The climate mitigation value of conserving the 549 million ha of tropical forest that remains intact is therefore significant but will soon dwindle if their rate of loss continues to accelerate.

3.
Sci Data ; 6(1): 232, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653863

RESUMO

Remotely sensed maps of global forest extent are widely used for conservation assessment and planning. Yet, there is increasing recognition that these efforts must now include elements of forest quality for biodiversity and ecosystem services. Such data are not yet available globally. Here we introduce two data products, the Forest Structural Condition Index (SCI) and the Forest Structural Integrity Index (FSII), to meet this need for the humid tropics. The SCI integrates canopy height, tree cover, and time since disturbance to distinguish short, open-canopy, or recently deforested stands from tall, closed-canopy, older stands typical of primary forest. The SCI was validated against estimates of foliage height diversity derived from airborne lidar. The FSII overlays a global index of human pressure on SCI to identify structurally complex forests with low human pressure, likely the most valuable for maintaining biodiversity and ecosystem services. These products represent an important step in maturation from conservation focus on forest extent to forest stands that should be considered "best of the last" in international policy settings.

4.
Glob Chang Biol ; 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578793

RESUMO

The Human Modification map differs in important ways from the map of the human footprint, such as its mapping of widespread direct modification of much of the world's polar regions. An extensive validation reveals large inaccuracies in the Human Modification map, and that the human footprint tends to better represent actual observable human pressures on the ground.

5.
Nature ; 567(7748): 311, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30890806

Assuntos
Clima , Florestas
6.
PLoS Biol ; 17(3): e3000158, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30860989

RESUMO

Conserving threatened species requires identifying where across their range they are being impacted by threats, yet this remains unresolved across most of Earth. Here, we present a global analysis of cumulative human impacts on threatened species by using a spatial framework that jointly considers the co-occurrence of eight threatening processes and the distribution of 5,457 terrestrial vertebrates. We show that impacts to species are widespread, occurring across 84% of Earth's surface, and identify hotspots of impacted species richness and coolspots of unimpacted species richness. Almost one-quarter of assessed species are impacted across >90% of their distribution, and approximately 7% are impacted across their entire range. These results foreshadow localised extirpations and potential extinctions without conservation action. The spatial framework developed here offers a tool for defining strategies to directly mitigate the threats driving species' declines, providing essential information for future national and global conservation agendas.


Assuntos
Vertebrados , Animais , Biodiversidade , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Extinção Biológica , Humanos
7.
Conserv Biol ; 33(5): 1219-1223, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30672033

RESUMO

Current conservation templates prioritize biogeographic regions with high intensity ecosystem values, such as exceptional species richness or threat. Intensity-based targets are an important consideration in global efforts, but they do not capture all available opportunities to conserve ecosystem values, including those that accrue in low intensity over large areas. We assess six globally-significant ecosystem values-intact wilderness, freshwater availability, productive marine environments, breeding habitat for migratory wildlife, soil carbon storage, and latitudinal potential for range shift in the face of climate change-to highlight opportunities for high-impact broadly-distributed contributions to global conservation. Nations can serve as a cohesive block of policy that can profoundly influence conservation outcomes. Contributions to global ecosystem values that exceed what is predicted by a nation's area alone, can give rise to countries with the capacity to act as 'conservation superpowers', such as Canada and Russia. For these conservation superpowers, a relatively small number of national policies can have environmental repercussions for the rest of the world.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Canadá , Federação Russa
9.
Nat Commun ; 9(1): 4621, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30397204

RESUMO

Predicting how species respond to human pressure is essential to anticipate their decline and identify appropriate conservation strategies. Both human pressure and extinction risk change over time, but their inter-relationship is rarely considered in extinction risk modelling. Here we measure the relationship between the change in terrestrial human footprint (HFP)-representing cumulative human pressure on the environment-and the change in extinction risk of the world's terrestrial mammals. We find the values of HFP across space, and its change over time, are significantly correlated to trends in species extinction risk, with higher predictive importance than environmental or life-history variables. The anthropogenic conversion of areas with low pressure values (HFP < 3 out of 50) is the most significant predictor of change in extinction risk, but there are biogeographical variations. Our framework, calibrated on past extinction risk trends, can be used to predict the impact of increasing human pressure on biodiversity.


Assuntos
Distribuição Animal , Biodiversidade , Evolução Biológica , Extinção Biológica , Animais , Conservação dos Recursos Naturais , Meio Ambiente , Humanos , Mamíferos , Modelos Biológicos , Modelos Estatísticos , Filogeografia , Densidade Demográfica , Crescimento Demográfico , Medição de Risco , Especificidade da Espécie
11.
Science ; 361(6402): 562-563, 2018 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-30093593
12.
Curr Biol ; 28(15): 2506-2512.e3, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-30057308

RESUMO

As human activities increasingly threaten biodiversity [1, 2], areas devoid of intense human impacts are vital refugia [3]. These wilderness areas contain high genetic diversity, unique functional traits, and endemic species [4-7]; maintain high levels of ecological and evolutionary connectivity [8-10]; and may be well placed to resist and recover from the impacts of climate change [11-13]. On land, rapid declines in wilderness [3] have led to urgent calls for its protection [3, 14]. In contrast, little is known about the extent and protection of marine wilderness [4, 5]. Here we systematically map marine wilderness globally by identifying areas that have both very little impact (lowest 10%) from 15 anthropogenic stressors and also a very low combined cumulative impact from these stressors. We discover that ∼13% of the ocean meets this definition of global wilderness, with most being located in the high seas. Recognizing that human influence differs across ocean regions, we repeat the analysis within each of the 16 ocean realms [15]. Realm-specific wilderness extent varies considerably, with >16 million km2 (8.6%) in the Warm Indo-Pacific, down to <2,000 km2 (0.5%) in Temperate Southern Africa. We also show that the marine protected area estate holds only 4.9% of global wilderness and 4.1% of realm-specific wilderness, very little of which is in biodiverse ecosystems such as coral reefs. Proactive retention of marine wilderness should now be incorporated into global strategies aimed at conserving biodiversity and ensuring that large-scale ecological and evolutionary processes continue. VIDEO ABSTRACT.


Assuntos
Conservação dos Recursos Naturais/estatística & dados numéricos , Oceanos e Mares , Meio Selvagem , Biodiversidade , Ecossistema
13.
Science ; 360(6390): 788-791, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29773750

RESUMO

In an era of massive biodiversity loss, the greatest conservation success story has been the growth of protected land globally. Protected areas are the primary defense against biodiversity loss, but extensive human activity within their boundaries can undermine this. Using the most comprehensive global map of human pressure, we show that 6 million square kilometers (32.8%) of protected land is under intense human pressure. For protected areas designated before the Convention on Biological Diversity was ratified in 1992, 55% have since experienced human pressure increases. These increases were lowest in large, strict protected areas, showing that they are potentially effective, at least in some nations. Transparent reporting on human pressure within protected areas is now critical, as are global targets aimed at efforts required to halt biodiversity loss.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Atividades Humanas , Humanos
14.
Nat Ecol Evol ; 2(4): 599-610, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29483681

RESUMO

As the terrestrial human footprint continues to expand, the amount of native forest that is free from significant damaging human activities is in precipitous decline. There is emerging evidence that the remaining intact forest supports an exceptional confluence of globally significant environmental values relative to degraded forests, including imperilled biodiversity, carbon sequestration and storage, water provision, indigenous culture and the maintenance of human health. Here we argue that maintaining and, where possible, restoring the integrity of dwindling intact forests is an urgent priority for current global efforts to halt the ongoing biodiversity crisis, slow rapid climate change and achieve sustainability goals. Retaining the integrity of intact forest ecosystems should be a central component of proactive global and national environmental strategies, alongside current efforts aimed at halting deforestation and promoting reforestation.


Assuntos
Biodiversidade , Sequestro de Carbono , Mudança Climática , Conservação dos Recursos Naturais , Agricultura Florestal , Florestas
15.
Ecol Lett ; 21(3): 365-375, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29314473

RESUMO

Protecting biomass carbon stocks to mitigate climate change has direct implications for biodiversity conservation. Yet, evidence that a positive association exists between carbon density and species richness is contrasting. Here, we test how this association varies (1) across spatial extents and (2) as a function of how strongly carbon and species richness depend on environmental variables. We found the correlation weakens when moving from larger extents, e.g. realms, to narrower extents, e.g. ecoregions. For ecoregions, a positive correlation emerges when both species richness and carbon density vary as functions of the same environmental variables (climate, soil, elevation). In 20% of tropical ecoregions, there are opportunities to pursue carbon conservation with direct biodiversity co-benefits, while other ecoregions require careful planning for both species and carbon to avoid potentially perverse outcomes. The broad assumption of a linear relationship between carbon and biodiversity can lead to undesired outcomes.


Assuntos
Biodiversidade , Carbono , Conservação dos Recursos Naturais , Biomassa , Solo
16.
Conserv Biol ; 32(1): 127-134, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28639356

RESUMO

To contribute to the aspirations of recent international biodiversity conventions, protected areas (PAs) must be strategically located and not simply established on economically marginal lands as they have in the past. With refined international commitments under the Convention on Biological Diversity to target protected areas in places of "importance to biodiversity," perhaps they may now be. We analyzed location biases in PAs globally over historic (pre-2004) and recent periods. Specifically, we examined whether the location of protected areas are more closely associated with high concentrations of threatened vertebrate species or with areas of low agricultural opportunity costs. We found that both old and new protected areas did not target places with high concentrations of threatened vertebrate species. Instead, they appeared to be established in locations that minimize conflict with agriculturally suitable lands. This entrenchment of past trends has substantial implications for the contributions these protected areas are making to international commitments to conserve biodiversity. If protected-area growth from 2004 to 2014 had strategically targeted unrepresented threatened vertebrates, >30 times more species (3086 or 2553 potential vs. 85 actual new species represented) would have been protected for the same area or the same cost as the actual expansion. With the land available for conservation declining, nations must urgently focus new protection on places that provide for the conservation outcomes outlined in international treaties.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Viés , Espécies em Perigo de Extinção , Vertebrados
17.
Conserv Biol ; 32(1): 116-126, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28664996

RESUMO

Wilderness areas are ecologically intact landscapes predominantly free of human uses, especially industrial-scale activities that result in substantial biophysical disturbance. This definition does not exclude land and resource use by local communities who depend on such areas for subsistence and bio-cultural connections. Wilderness areas are important for biodiversity conservation and sustain key ecological processes and ecosystem services that underpin planetary life-support systems. Despite these widely recognized benefits and values of wilderness, they are insufficiently protected and are consequently being rapidly eroded. There are increasing calls for multilateral environmental agreements to make a greater and more systematic contribution to wilderness conservation before it is too late. We created a global map of remaining terrestrial wilderness following the established last-of-the-wild method, which identifies the 10% of areas with the lowest human pressure within each of Earth's 62 biogeographic realms and identifies the 10 largest contiguous areas and all contiguous areas >10,000 km2 . We used our map to assess wilderness coverage by the World Heritage Convention and to identify gaps in coverage. We then identified large nationally designated protected areas with good wilderness coverage within these gaps. One-quarter of natural and mixed (i.e., sites of both natural and cultural value) World Heritage Sites (WHS) contained wilderness (total of 545,307 km2 ), which is approximately 1.8% of the world's wilderness extent. Many WHS had excellent wilderness coverage, for example, the Okavango Delta in Botswana (11,914 km2 ) and the Central Suriname Nature Reserve (16,029 km2 ). However, 22 (35%) of the world's terrestrial biorealms had no wilderness representation within WHS. We identified 840 protected areas of >500 km2 that were predominantly wilderness (>50% of their area) and represented 18 of the 22 missing biorealms. These areas offer a starting point for assessing the potential for the designation of new WHSs that could help increase wilderness representation on the World Heritage list. We urge the World Heritage Convention to ensure that the ecological integrity and outstanding universal value of existing WHS with wilderness values are preserved.


Assuntos
Ecossistema , Meio Selvagem , Biodiversidade , Conservação dos Recursos Naturais , Ecologia , Humanos
18.
Sci Data ; 4: 170187, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29231923

RESUMO

Wilderness areas, defined as areas free of industrial scale activities and other human pressures which result in significant biophysical disturbance, are important for biodiversity conservation and sustaining the key ecological processes underpinning planetary life-support systems. Despite their importance, wilderness areas are being rapidly eroded in extent and fragmented. Here we present the most up-to-date temporally inter-comparable maps of global terrestrial wilderness areas, which are essential for monitoring changes in their extent, and for proactively planning conservation interventions to ensure their preservation. Using maps of human pressure on the natural environment for 1993 and 2009, we identified wilderness as all 'pressure free' lands with a contiguous area >10,000 km2. These places are likely operating in a natural state and represent the most intact habitats globally. We then created a regionally representative map of wilderness following the well-established 'Last of the Wild' methodology; which identifies the 10% area with the lowest human pressure within each of Earth's 60 biogeographic realms, and identifies the ten largest contiguous areas, along with all contiguous areas >10,000 km2.

19.
Nature ; 550(7674): 48-49, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28953876
20.
Curr Biol ; 26(21): 2929-2934, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27618267

RESUMO

Humans have altered terrestrial ecosystems for millennia [1], yet wilderness areas still remain as vital refugia where natural ecological and evolutionary processes operate with minimal human disturbance [2-4], underpinning key regional- and planetary-scale functions [5, 6]. Despite the myriad values of wilderness areas-as critical strongholds for endangered biodiversity [7], for carbon storage and sequestration [8], for buffering and regulating local climates [9], and for supporting many of the world's most politically and economically marginalized communities [10]-they are almost entirely ignored in multilateral environmental agreements. This is because they are assumed to be relatively free from threatening processes and therefore are not a priority for conservation efforts [11, 12]. Here we challenge this assertion using new comparable maps of global wilderness following methods established in the original "last of the wild" analysis [13] to examine the change in extent since the early 1990s. We demonstrate alarming losses comprising one-tenth (3.3 million km2) of global wilderness areas over the last two decades, particularly in the Amazon (30%) and central Africa (14%). We assess increases in the protection of wilderness over the same time frame and show that these efforts are failing to keep pace with the rate of wilderness loss, which is nearly double the rate of protection. Our findings underscore an immediate need for international policies to recognize the vital values of wilderness and the unprecedented threats they face and to underscore urgent large-scale, multifaceted actions needed to maintain them.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Política Ambiental/legislação & jurisprudência , Meio Selvagem , África Central , Conservação dos Recursos Naturais/legislação & jurisprudência , América do Sul
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