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1.
PLoS One ; 15(10): e0239182, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33112860

RESUMO

The koala (Phascolarctos cinereus) is currently listed by both the IUCN and the Australian Governments' Threatened Species Scientific Committee as vulnerable to extinction with an overall decreasing population trend. It is unknown exactly how many koalas remain in the wild, but it is known that habitat fragmentation and bushfires have ultimately contributed to the decline of the koala all over Australia. This novel study is a retrospective analysis of data over a 29-year period (1989-2018) using records for 12,543 sightings and clinical care admissions for wild koalas from the major koala hot-spots (Port Stephens, port Macquarie and Lismore) in New South Wales, Australia. This study aims to understand the long-term patterns and trends of key stressors that are contributing to the decline of koalas in New South Wales, and the synergic interactions of factors such as rescue location, sex and age of the koala, and if their decline is influenced progressively by year. The main findings of this retrospective analysis indicated that between all 3 rescue sites, the most common prognosis was disease, the most common disease was signs of chlamydia, and the most common outcome was release. The location where the highest number of koalas were found prior to being reported as sighted or admitted into clinical care was within the regional area of Lismore. Furthermore, sex was not a discriminating factor when it came to prognosis or outcome, but age was significant. Finally, incidents of disease were found to increase over long-term, whereas release decreased over time and euthanasia increased. The wealth of data available to us and the retrospective analysis enabled us in a way to 'zoom out' and reveal how the key environmental stressors have fluctuated spatially and temporally. In conclusion, our data provides strong evidence of added pressures of increased human population growth in metropolitan zones, which increases risks of acute environmental trauma and proximate stressors such as vehicle collisions and dog-attacks as well as increased sightings of virtually healthy koalas found in exposed environments. Thus our 'zoom out' approach provides support that there is an urgent need to strengthen on-ground management, bushfire control regimes, environmental planning and governmental policy actions that should hopefully reduce the proximate environmental stressors in a step wise approach. This will ensure that in the next decade (beyond 2020), NSW koalas will hopefully start to show reversed trends and patterns in exposure to environmental trauma and disease, and population numbers will return towards recovery and stability.


Assuntos
Espécies em Perigo de Extinção , Phascolarctidae , Animais , Infecções por Chlamydia/veterinária , Conservação dos Recursos Naturais/história , Conservação dos Recursos Naturais/tendências , Demografia/história , Demografia/tendências , Ecossistema , Espécies em Perigo de Extinção/tendências , Feminino , História do Século XX , História do Século XXI , Masculino , New South Wales , Phascolarctidae/microbiologia , Prognóstico , Estudos Retrospectivos
2.
PLoS One ; 15(9): e0239006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32960903

RESUMO

To prevent and control non-point source pollution, many policies have been carried out by government in China. However, the effectiveness of these policies has rarely been evaluated. In this study, the potential and spatial distribution of agricultural non-point source pollution in the Baiyangdian Basin are reported. This investigation considers multiple parameters under various policies with county as a basic unit. The results for the potential pollution from chemical oxygen demand (COD), ammonia nitrogen (NH3-N), total nitrogen (TN) and total phosphorus (TP) are 60.89×104, 3.93×104, 87.05×104 and 15.10×104 Mg, with corresponding intensities of 190, 12, 272 and 47 kg ha-1 for the Baiyangdian Basin in 2016. The highest pollution from COD is attributed to livestock and poultry breeding, whereas TN and TP are dominantly produced by rural domestic sources, and NH3-N is mostly derived from planting. Spatially, distribution of the counties producing larger non-point source pollution presented a northeast to southwest direction, consistent with the Taihang mountain alignment in the basin. The counties with high pollution intensities are mostly in the south and east of the basin. Agricultural non-point source pollution control and prevention policies contributed in pollution reduction. Compared with 2016, the total potential pollution of COD, NH3-N, TN and TP in 2020 decrease by 45.1%, 14.7%, 37.9% and 37.4%, respectively, whereas for an assumed future time (F2), the decreases are 59%, 51.4%, 56.2% and 55.7%, respectively. Prevention measures should focus on reducing pollution from livestock and poultry breeding as well as planting.


Assuntos
Monitoramento Ambiental/métodos , Poluição Difusa/análise , Poluição Difusa/economia , Agricultura , Amônia/análise , Animais , Análise da Demanda Biológica de Oxigênio/métodos , China , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Política Ambiental/tendências , Poluição Ambiental/análise , Poluição Ambiental/economia , Gado , Nitrogênio/análise , Fósforo/análise , Aves Domésticas , Rios , Poluentes Químicos da Água/análise
4.
PLoS One ; 15(9): e0239525, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970736

RESUMO

Rapid changes in climate and land use threaten the persistence of wildlife species. Understanding where species are likely to occur now and in the future can help identify areas that are resistant to change over time and guide conservation planning. We estimated changes in species distribution patterns and spatial resistance in five future scenarios for the New England region of the northeastern United States. We present scenario-specific distribution change maps for nine harvested wildlife species, identifying regions of increasing, decreasing, or stable habitat suitability within each scenario. Next, we isolated areas where species occurrence probability is high (p > 0.7) and resistant to change across all future scenarios. Resistance was also evaluated relative to current land protection to identify patterns in and out of Protected Areas (PAs). Generally, species distributions declined in area over the 50-year assessment period (2010-2060), with the greatest average declines occurring for moose (-40.9%) and wild turkey (-22.1%). Species resistance varied considerably across the region, with coyote demonstrating the highest average regional resistance (91.81% of the region) and moose demonstrating the lowest (0.76% of the region). At the state level, average focal species resistance was highest in Maine (the largest state) and lowest in Massachusetts. Many of the focal species showed high overlap in resistance and land protection. Coyote, white-tailed deer, and black bear had the highest probability of resistance, given protection, while moose and wild turkey had the highest probability of protection, given resistance. Overall, relatively small portions of New England-ranging between 0.25% and 21.12%-were both protected and resistant for the focal species. Our results provide estimates of resistance that can inform conservation planning for commonly harvested species that are important ecologically, economically, and culturally to the region. Expanding protected area coverage to include resistant areas may provide longer term benefits to these species.


Assuntos
Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Animais , Animais Selvagens , Conservação dos Recursos Naturais/tendências , Coleta de Dados , Demografia/métodos , Ecologia , Ecossistema , New England
5.
Nature ; 585(7826): 551-556, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908312

RESUMO

Increased efforts are required to prevent further losses to terrestrial biodiversity and the ecosystem services that it  provides1,2. Ambitious targets have been proposed, such as reversing the declining trends in biodiversity3; however, just feeding the growing human population will make this a challenge4. Here we use an ensemble of land-use and biodiversity models to assess whether-and how-humanity can reverse the declines in terrestrial biodiversity caused by habitat conversion, which is a major threat to biodiversity5. We show that immediate efforts, consistent with the broader sustainability agenda but of unprecedented ambition and coordination, could enable the provision of food for the growing human population while reversing the global terrestrial biodiversity trends caused by habitat conversion. If we decide to increase the extent of land under conservation management, restore degraded land and generalize landscape-level conservation planning, biodiversity trends from habitat conversion could become positive by the mid-twenty-first century on average across models (confidence interval, 2042-2061), but this was not the case for all models. Food prices could increase and, on average across models, almost half (confidence interval, 34-50%) of the future biodiversity losses could not be avoided. However, additionally tackling the drivers of land-use change could avoid conflict with affordable food provision and reduces the environmental effects of the food-provision system. Through further sustainable intensification and trade, reduced food waste and more plant-based human diets, more than two thirds of future biodiversity losses are avoided and the biodiversity trends from habitat conversion are reversed by 2050 for almost all of the models. Although limiting further loss will remain challenging in several biodiversity-rich regions, and other threats-such as climate change-must be addressed to truly reverse the declines in biodiversity, our results show that ambitious conservation efforts and food system transformation are central to an effective post-2020 biodiversity strategy.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Política Ambiental/tendências , Atividades Humanas/tendências , Dieta , Dieta Vegetariana/tendências , Abastecimento de Alimentos , Humanos , Desenvolvimento Sustentável/tendências
6.
PLoS One ; 15(8): e0224958, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756568

RESUMO

Tracking changes in total biomass production or land productivity is an essential part of monitoring land transformations and long-term alterations of the health and productive capacity of land that are typically associated with land degradation. Persistent declines in land productivity impact many terrestrial ecosystem services that form the basis for sustainable livelihoods of human communities. Protected areas (PAs) are key to globally conserve biodiversity and ecosystem services that are critical for human well-being, and cover about 15% of the land worldwide. Here we globally assess the trends in land productivity in PAs of at least 10 km2 and in their unprotected surroundings (10 km buffers) from 1999 to 2013. We quantify the percentage of the protected and unprotected land that shows stable, increasing or decreasing trends in land productivity, quantified as long-term (15 year) changes in above-ground biomass derived from satellite-based observations with a spatial resolution of 1 km. We find that 44% of the land in PAs globally has retained the productivity at stable levels from 1999 to 2013, compared to 42% of stable productivity in the unprotected land around PAs. Persistent increases in productivity are more common in the unprotected lands around PAs (32%) than within PAs (18%) globally, while about 14% of the protected land and 12% of the unprotected land around PAs has experienced declines in land productivity. Oceania has the highest percentage of land with stable productivity in PAs (57%), whereas Europe has the lowest percentage (38%) and also the largest share of protected land with increasing land productivity (32%). We discuss the observed differences between PAs and unprotected lands, and between different parts of the world, in relation to different types and levels of human activities and their impact on land productivity. Our assessment of land productivity dynamics helps to characterise the state, pressures and changes in and around protected areas globally. Further research may focus on more detailed analyses to disentangle the relative contribution of specific drivers (from climate change to land use change) and their interaction with land productivity dynamics and potential land degradation in different regions of the world.


Assuntos
Biomassa , Conservação dos Recursos Naturais/tendências , Ecossistema , Biodiversidade , Eficiência , Geografia , História do Século XX , História do Século XXI , Humanos
7.
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
8.
Nature ; 584(7821): 403-409, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760000

RESUMO

The tuatara (Sphenodon punctatus)-the only living member of the reptilian order Rhynchocephalia (Sphenodontia), once widespread across Gondwana1,2-is an iconic species that is endemic to New Zealand2,3. A key link to the now-extinct stem reptiles (from which dinosaurs, modern reptiles, birds and mammals evolved), the tuatara provides key insights into the ancestral amniotes2,4. Here we analyse the genome of the tuatara, which-at approximately 5 Gb-is among the largest of the vertebrate genomes yet assembled. Our analyses of this genome, along with comparisons with other vertebrate genomes, reinforce the uniqueness of the tuatara. Phylogenetic analyses indicate that the tuatara lineage diverged from that of snakes and lizards around 250 million years ago. This lineage also shows moderate rates of molecular evolution, with instances of punctuated evolution. Our genome sequence analysis identifies expansions of proteins, non-protein-coding RNA families and repeat elements, the latter of which show an amalgam of reptilian and mammalian features. The sequencing of the tuatara genome provides a valuable resource for deep comparative analyses of tetrapods, as well as for tuatara biology and conservation. Our study also provides important insights into both the technical challenges and the cultural obligations that are associated with genome sequencing.


Assuntos
Evolução Molecular , Genoma/genética , Filogenia , Répteis/genética , Animais , Conservação dos Recursos Naturais/tendências , Feminino , Genética Populacional , Lagartos/genética , Masculino , Anotação de Sequência Molecular , Nova Zelândia , Caracteres Sexuais , Serpentes/genética , Sintenia
9.
PLoS One ; 15(6): e0234960, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32603348

RESUMO

Documenting changes in ecosystem extent and protection is essential to understanding status of biodiversity and related ecosystem services and have direct applications to measuring Essential Biodiversity Variables, Targets under the Convention on Biological Diversity (CBD), and IUCN Red List of Ecosystems. We developed both potential and current distribution maps of terrestrial ecosystem types for the temperate and tropical Americas; with "potential" estimating where a type would likely occur today had there not been prior land conversion for modern land uses. We utilized a hierarchical classification to describe and map natural ecosystem types at six levels of thematic detail, with lower thematic levels defining more units each with narrower floristic range than upper levels. Current land use/land cover was derived using available global data on human land use intensity and combined with the potential distribution maps to estimate long-term change in extent for each ecosystem type. We also assessed representation of ecosystem types within protected areas as defined by IUCN I-VI land status categories. Of the 749 ecosystem types assessed, represented at 5th (n = 315) vs. 6th (n = 433) levels of the classification hierarchy, 5 types (1.6%) and 31 types (7.1%), respectively, have lost >90% of their potential extent. Some 66 types (20.9%) and 141 types (32.5%), respectively, have lost >50% of their potential extent; thus, crossing thresholds of Vulnerable status under IUCN Red List criterion A3. For ecosystem type representation within IUCN protected area classes, with reference to potential extent of each type, 111 (45.3%) and 125 (28.8%) of types, respectively, have higher representation (>17%) than CBD 2020 targets. Twelve types (3.8%) and 23 (5.3%) of types, respectively, are represented with <1% within protected areas. We illustrate an option for visualizing and reporting on CBD targets (2020 and proposed post-2020) for ecosystem representativeness using both potential extent as a baseline.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/tendências , Ecologia/métodos , Dispersão Vegetal , América , Conservação dos Recursos Naturais/estatística & dados numéricos , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Monitorização de Parâmetros Ecológicos/tendências , Ecologia/tendências , Floresta Úmida , Clima Tropical
10.
Am J Primatol ; 82(8): e23176, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32686188

RESUMO

The emergence of SARS-CoV-2 in late 2019 and human responses to the resulting COVID-19 pandemic in early 2020 have rapidly changed many aspects of human behavior, including our interactions with wildlife. In this commentary, we identify challenges and opportunities at human-primate interfaces in light of COVID-19, focusing on examples from Asia, and make recommendations for researchers working with wild primates to reduce zoonosis risk and leverage research opportunities. First, we briefly review the evidence for zoonotic origins of SARS-CoV-2 and discuss risks of zoonosis at the human-primate interface. We then identify challenges that the pandemic has caused for primates, including reduced nutrition, increased intraspecific competition, and increased poaching risk, as well as challenges facing primatologists, including lost research opportunities. Subsequently, we highlight opportunities arising from pandemic-related lockdowns and public health messaging, including opportunities to reduce the intensity of problematic human-primate interfaces, opportunities to reduce the risk of zoonosis between humans and primates, opportunities to reduce legal and illegal trade in primates, new opportunities for research on human-primate interfaces, and opportunities for community education. Finally, we recommend specific actions that primatologists should take to reduce contact and aggression between humans and primates, to reduce demand for primates as pets, to reduce risks of zoonosis in the context of field research, and to improve understanding of human-primate interfaces. Reducing the risk of zoonosis and promoting the well-being of humans and primates at our interfaces will require substantial changes from "business as usual." We encourage primatologists to help lead the way.


Assuntos
Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Doenças dos Primatas/prevenção & controle , Zoonoses/prevenção & controle , Animais , Conservação dos Recursos Naturais/tendências , Infecções por Coronavirus/transmissão , Comportamento Alimentar/fisiologia , Humanos , Pneumonia Viral/transmissão , Doenças dos Primatas/transmissão , Doenças dos Primatas/virologia , Primatas , Fatores de Risco , Zoonoses/transmissão
11.
PLoS One ; 15(6): e0234560, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32542054

RESUMO

The Global Earth Overshoot Day, the date when all annually available natural resources are consumed, is set for July this year. For densely populated European countries like Germany or Switzerland, that specific day is due even earlier (May). To overcome such an unsustainable lifestyle, immediate actions are required, which includes substantial educational efforts. As the model of "Sustainable Development" is complex, appropriate pedagogical actions need to support cognitive learning, critical thinking and behavioural actions. Knowledge about individual conceptions in relation to the Environment, Nature and Ecological Footprints contributes to pre-conditions to succeed. To what extent present teaching methods influenced individual conceptions during the first UN-decade regarding those terms is illustrated by 464 Swiss-German university freshmen who participated in our paper-pencil test, which is based on four open questions. The term of Environment was perceived as the sum of biocentric, ecocentric and anthropocentric views. The participants often equated the term to Nature and associated it with positive feelings or emotions. Therefore, calm, joy and aesthetic appreciation were predominantly named. Regardless of the concept, humans were perceived as the Greatest Environmental Threat. In contrast, recommendations to reduce Environmental Footprints regarding mobility & transport, waste avoidance and consumption differ. Following a binary logistic regression analysis, the involvement of the Inclusion of Self Scale (INS) was used as an explanatory variable to detect patterns of those conceptions. Relating sustainable concepts, natural resources were frequently named exceeding saving water and energy or other association dealt with second-hand issues or regional/ seasonal usages. Such ideas are shaped by experiences and scientific expertise.


Assuntos
Estudantes/psicologia , Desenvolvimento Sustentável , Universidades , Conservação dos Recursos Naturais/tendências , Humanos , Inquéritos e Questionários , Desenvolvimento Sustentável/tendências
13.
Proc Natl Acad Sci U S A ; 117(16): 8683-8691, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32312801

RESUMO

April 22, 2020, marks the 50th anniversary of Earth Day and the birth of the modern environmental movement. As we look back over the past half century, we can gain significant insights into the evolving human imprint on Earth's biophysical systems, and the role of science and scientists in driving societal transitions toward greater sustainability. Science is a foundation for such transitions, but it is not enough. Rather, it is through wide collaborations across fields, including law, economics, and politics, and through direct engagement with civil society, that science can illuminate a better path forward. This is illustrated through a number of case studies highlighting the role of scientists in leading positive societal change, often in the face of strong oppositional forces. The past five decades reveal significant triumphs of environmental protection, but also notable failures, which have led to the continuing deterioration of Earth's natural systems. Today, more than ever, these historical lessons loom large as we face increasingly complex and pernicious environmental problems.


Assuntos
Conservação dos Recursos Naturais/história , Planeta Terra , Política , Sociedades/história , Desenvolvimento Sustentável/história , Conservação dos Recursos Naturais/tendências , História do Século XX , História do Século XXI , Humanos , Desenvolvimento Sustentável/tendências , Estados Unidos
14.
Proc Natl Acad Sci U S A ; 117(13): 7271-7275, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32152101

RESUMO

Evidence for global insect declines mounts, increasing our need to understand underlying mechanisms. We test the nutrient dilution (ND) hypothesis-the decreasing concentration of essential dietary minerals with increasing plant productivity-that particularly targets insect herbivores. Nutrient dilution can result from increased plant biomass due to climate or CO2 enrichment. Additionally, when considering long-term trends driven by climate, one must account for large-scale oscillations including El Niño Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), and Pacific Decadal Oscillation (PDO). We combine long-term datasets of grasshopper abundance, climate, plant biomass, and end-of-season foliar elemental content to examine potential drivers of abundance cycles and trends of this dominant herbivore. Annual grasshopper abundances in 16- and 22-y time series from a Kansas prairie revealed both 5-y cycles and declines of 2.1-2.7%/y. Climate cycle indices of spring ENSO, summer NAO, and winter or spring PDO accounted for 40-54% of the variation in grasshopper abundance, mediated by effects of weather and host plants. Consistent with ND, grass biomass doubled and foliar concentrations of N, P, K, and Na-nutrients which limit grasshopper abundance-declined over the same period. The decline in plant nutrients accounted for 25% of the variation in grasshopper abundance over two decades. Thus a warming, wetter, more CO2-enriched world will likely contribute to declines in insect herbivores by depleting nutrients from their already nutrient-poor diet. Unlike other potential drivers of insect declines-habitat loss, light and chemical pollution-ND may be widespread in remaining natural areas.


Assuntos
Conservação dos Recursos Naturais/tendências , Demografia/tendências , Gafanhotos , Animais , Biomassa , Mudança Climática/estatística & dados numéricos , Ecossistema , El Niño Oscilação Sul , Pradaria , Herbivoria , Insetos , Kansas , Nutrientes , Poaceae , Estações do Ano , Tempo (Meteorologia)
15.
Nat Commun ; 11(1): 1258, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152272

RESUMO

Deforestation can increase the transmission of malaria. Here, we build upon the existing link between malaria risk and deforestation by investigating how the global demand for commodities that increase deforestation can also increase malaria risk. We use a database of trade relationships to link the consumption of deforestation-implicated commodities in developed countries to estimates of country-level malaria risk in developing countries. We estimate that about 20% of the malaria risk in deforestation hotspots is driven by the international trade of deforestation-implicated export commodities, such as timber, wood products, tobacco, cocoa, coffee and cotton. By linking malaria risk to final consumers of commodities, we contribute information to support demand-side policy measures to complement existing malaria control interventions, with co-benefits for reducing deforestation and forest disturbance.


Assuntos
Comércio , Conservação dos Recursos Naturais , Internacionalidade , Malária/transmissão , Agricultura/estatística & dados numéricos , Agricultura/tendências , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Ecologia , Economia , Monitoramento Ambiental , Florestas , Geografia , Humanos , Malária/epidemiologia , Modelos Teóricos , Políticas , Fatores de Risco , Árvores , Madeira
16.
PLoS One ; 15(3): e0230209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32160257

RESUMO

Agricultural frontier expansion into the Amazon over the last four decades has created million hectares of fragmented forests. While many species undergo local extinctions within remaining forest patches, this may be compensated by native species from neighbouring open-habitat areas potentially invading these patches, particularly as forest habitats become increasingly degraded. Here, we examine the effects of habitat loss, fragmentation and degradation on small mammal assemblages in a southern Amazonian deforestation frontier, while accounting for species-specific degree of forest-dependency. We surveyed small mammals at three continuous forest sites and 19 forest patches of different sizes and degrees of isolation. We further sampled matrix habitats adjacent to forest patches, which allowed us to classify each species according to forest-dependency and generate a community-averaged forest-dependency index for each site. Based on 21,568 trap-nights, we recorded 970 small mammals representing 20 species: 12 forest-dependents, 5 matrix-tolerants and 3 open-habitat specialists. Across the gradient of forest patch size, small mammal assemblages failed to show the typical species-area relationship, but this relationship held true when either species abundance or composition was considered. Species composition was further mediated by community-averaged forest-dependency, so that smaller forest patches were occupied by a lower proportion of forest-dependent rodents and marsupials. Both species richness and abundance increased in less isolated fragments surrounded by structurally simplified matrix habitats (e.g. active or abandoned cattle pastures). While shorter distances between forest patches may favour small mammal abundances, forest area and matrix complexity dictated which species could persist within forest fragments according to their degree of forest-dependency. Small mammal local extinctions in small forest patches within Amazonian deforestation frontiers are therefore likely offset by the incursion of open-habitat species. To preclude the dominance of those species, and consequent losses of native species and associated ecosystem functions, management actions should limit or reduce areas dedicated to pasture, additionally maintaining more structurally complex matrix habitats across fragmented landscapes.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/tendências , Mamíferos , Animais , Brasil , Ecossistema , Espécies em Perigo de Extinção/tendências , Florestas , Dinâmica Populacional , Floresta Úmida , Rios , Especificidade da Espécie , Árvores
17.
Artigo em Inglês | MEDLINE | ID: mdl-32164299

RESUMO

In the past decades, food consumption in China has undergone a rapid increase and a significant structure transition, as a result of population growth and economic development. The food system is increasingly threatening the environment by depleting water resources, deteriorating water bodies, aggravating climate change, degrading ecosystems, etc. It is significant to understand how food consumption affected the environment and how its impacts were driven in the historical period. This study reveals the environmental impacts of China's food system from 1961 to 2017 from a consumption perspective by assessing water, carbon, and ecological footprints. The logarithmic mean Divisia index method was used to examine the drivers of the growing environmental footprints. The assessment results show that all three environmental footprints have had a drastic increase of more than two times during the studied period, which indicates the high environmental pressure posed by food consumption. We also found that, before the 1980s, the main driving forces of the increasing footprints were population and per capita energy intake. From 1984, the diet pattern started to take a positive effect and then became the dominant driver of the growing environmental footprints after the end of the 1990s.


Assuntos
Pegada de Carbono , Dieta , Ecossistema , Água , Carbono/metabolismo , China , Conservação dos Recursos Naturais/tendências , Dieta/tendências , Humanos , Água/metabolismo
18.
PLoS One ; 15(3): e0229614, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126070

RESUMO

The forests of Borneo-the third largest island on the planet-sustain some of the highest biodiversity and carbon storage in the world. The forests also provide vital ecosystem services and livelihood support for millions of people in the region, including many indigenous communities. The Pan-Borneo Highway and several hydroelectric dams are planned or already under construction in Sarawak, a Malaysian state comprising part of the Borneo. This development seeks to enhance economic growth and regional connectivity, support community access to services, and promote industrial development. However, the implications of the development of highway and dams for forest integrity, biodiversity and ecosystem services remained largely unreported. We assessed these development projects using fine-scale biophysical and environmental data and found several environmental and socioeconomic risks associated with the projects. The highway and hydroelectric dam projects will impact 32 protected areas including numerous key habitats of threatened species such as the proboscis monkey (Nasalis larvatus), Sarawak surili (Presbytis chrysomelas), Bornean orangutans (Pongo pygmaeus) and tufted ground squirrel (Rheithrosciurus macrotis). Under its slated development trajectory, the local and trans-national forest connectivity between Malaysian Borneo and Indonesian Borneo would also be substantially diminished. Nearly ~161 km of the Pan-Borneo Highway in Sarawak will traverse forested landscapes and ~55 km will traverse carbon-rich peatlands. The 13 hydroelectric dam projects will collectively impact ~1.7 million ha of forest in Sarawak. The consequences of planned highway and hydroelectric dams construction will increase the carbon footprint of development in the region. Moreover, many new road segments and hydroelectric dams would be built on steep slopes in high-rainfall zones and forested areas, increasing both construction and ongoing maintenance costs. The projects would also alter livelihood activities of downstream communities, risking their long-term sustainability. Overall, our findings identify major economic, social and environmental risks for several planned road segments in Sarawak-such as those between Telok Melano and Kuching; Sibu and Bintulu; and in the Lambir, Limbang and Lawas regions-and dam projects-such as Tutoh, Limbang, Lawas, Baram, Linau, Ulu Air and Baleh dams. Such projects need to be reviewed to ensure they reflect Borneo's unique environmental and forest ecosystem values, the aspirations of local communities and long-term sustainability of the projects rather than being assessed solely on their short-term economic returns.


Assuntos
Conservação dos Recursos Naturais/tendências , Florestas , Desenvolvimento Sustentável/tendências , Animais , Biodiversidade , Bornéu , Sequestro de Carbono , Mudança Climática , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Desenvolvimento Econômico , Ecossistema , Espécies em Perigo de Extinção , Humanos , Indonésia , Malásia , Centrais Elétricas/tendências , Política Pública , Desenvolvimento Sustentável/economia , Desenvolvimento Sustentável/legislação & jurisprudência
19.
PLoS One ; 15(2): e0228090, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023270

RESUMO

Globally, cities are growing rapidly in size and density and this has caused profound impacts on urban forest ecosystems. Urbanization requiring deforestation reduces ecosystem services that benefit both city dwellers and biodiversity. Understanding spatial and temporal patterns of vegetation changes associated with urbanization is thus a vital component of future sustainable urban development. We used Landsat time series data for three decades from 1988 to 2018 to characterize changes in vegetation cover and habitat connectivity in the Perth Metropolitan Area, in a rapidly urbanising Australian biodiversity hotspot, as a case study to understand the impacts of urbanization on urban forests. Moreover, as golf courses are a major component in urban areas, we assessed the role of golf courses in maintaining vegetation cover and creating habitat connectivity. To do this we employed (1) land use classification with post-classification change detection, and (2) Morphological Spatial Pattern Analysis (MSPA). Over 17,000 ha of vegetation were cleared and the area of vegetation contributing to biodiversity connectivity was reduced significantly over the three decades. The spatial patterns of vegetation loss and gain were different in each of the three decades (1988-2018) reflecting the implementation of urban planning. Furthermore, MSPA analysis showed that the reduction in vegetation cover led to habitat fragmentation with a significant decrease in the core and bridge classes and an increase in isolated patches in the urban landscape. Golf courses played a useful role in maintaining vegetation cover and contributing to connectivity in a regional biodiversity hotspot. Our findings suggest that for future urban expansion, urban planning needs to more carefully consider the impacts of deforestation on connectivity in the landscape. Moreover, there is a need to take into consideration opportunities for off-reserve conservation in smaller habitat fragments such as in golf courses in sustainable urban management.


Assuntos
Conservação dos Recursos Naturais/tendências , Urbanização , Ecossistema , Golfe , Análise Espacial
20.
Nat Commun ; 11(1): 993, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080191

RESUMO

High numbers of threatened species might be expected to occur where overall species richness is also high; however, this explains only a proportion of the global variation in threatened species richness. Understanding why many areas have more or fewer threatened species than would be expected given their species richness, and whether that is consistent across taxa, is essential for identifying global conservation priorities. Here, we show that, after controlling for species richness, environmental factors, such as temperature and insularity, are typically more important than human impacts for explaining spatial variation in global threatened species richness. Human impacts, nevertheless, have an important role, with relationships varying between vertebrate groups and zoogeographic regions. Understanding this variation provides a framework for establishing global conservation priorities, identifying those regions where species are inherently more vulnerable to the effects of threatening human processes, and forecasting how threatened species might be distributed in a changing world.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Anfíbios , Animais , Aves , Clima , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Ecossistema , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Extinção Biológica , Humanos , Mamíferos , Modelos Biológicos , Répteis , Análise Espaço-Temporal
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