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1.
Nature ; 585(7826): 545-550, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32968258

RESUMO

To constrain global warming, we must strongly curtail greenhouse gas emissions and capture excess atmospheric carbon dioxide1,2. Regrowing natural forests is a prominent strategy for capturing additional carbon3, but accurate assessments of its potential are limited by uncertainty and variability in carbon accumulation rates2,3. To assess why and where rates differ, here we compile 13,112 georeferenced measurements of carbon accumulation. Climatic factors explain variation in rates better than land-use history, so we combine the field measurements with 66 environmental covariate layers to create a global, one-kilometre-resolution map of potential aboveground carbon accumulation rates for the first 30 years of natural forest regrowth. This map shows over 100-fold variation in rates across the globe, and indicates that default rates from the Intergovernmental Panel on Climate Change (IPCC)4,5 may underestimate aboveground carbon accumulation rates by 32 per cent on average and do not capture eight-fold variation within ecozones. Conversely, we conclude that maximum climate mitigation potential from natural forest regrowth is 11 per cent lower than previously reported3 owing to the use of overly high rates for the location of potential new forest. Although our data compilation includes more studies and sites than previous efforts, our results depend on data availability, which is concentrated in ten countries, and data quality, which varies across studies. However, the plots cover most of the environmental conditions across the areas for which we predicted carbon accumulation rates (except for northern Africa and northeast Asia). We therefore provide a robust and globally consistent tool for assessing natural forest regrowth as a climate mitigation strategy.


Assuntos
Sequestro de Carbono , Carbono/metabolismo , Agricultura Florestal/estatística & dados numéricos , Agricultura Florestal/tendências , Florestas , Mapeamento Geográfico , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Conservação dos Recursos Naturais , Coleta de Dados , Recuperação e Remediação Ambiental , Aquecimento Global/prevenção & controle , Internacionalidade , Cinética
2.
Nature ; 583(7814): 72-77, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612223

RESUMO

Forests provide a series of ecosystem services that are crucial to our society. In the European Union (EU), forests account for approximately 38% of the total land surface1. These forests are important carbon sinks, and their conservation efforts are vital for the EU's vision of achieving climate neutrality by 20502. However, the increasing demand for forest services and products, driven by the bioeconomy, poses challenges for sustainable forest management. Here we use fine-scale satellite data to observe an increase in the harvested forest area (49 per cent) and an increase in biomass loss (69 per cent) over Europe for the period of 2016-2018 relative to 2011-2015, with large losses occurring on the Iberian Peninsula and in the Nordic and Baltic countries. Satellite imagery further reveals that the average patch size of harvested area increased by 34 per cent across Europe, with potential effects on biodiversity, soil erosion and water regulation. The increase in the rate of forest harvest is the result of the recent expansion of wood markets, as suggested by econometric indicators on forestry, wood-based bioenergy and international trade. If such a high rate of forest harvest continues, the post-2020 EU vision of forest-based climate mitigation may be hampered, and the additional carbon losses from forests would require extra emission reductions in other sectors in order to reach climate neutrality by 20503.


Assuntos
Agricultura Florestal/estatística & dados numéricos , Agricultura Florestal/tendências , Florestas , Biodiversidade , Biomassa , Sequestro de Carbono , Monitoramento Ambiental , Política Ambiental/economia , Política Ambiental/legislação & jurisprudência , Europa (Continente) , União Europeia/economia , Agricultura Florestal/economia , Agricultura Florestal/legislação & jurisprudência , Aquecimento Global/prevenção & controle , História do Século XXI , Imagens de Satélites , Madeira/economia
12.
Nat Commun ; 9(1): 4839, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30446752

RESUMO

Trade-offs and synergies in the supply of forest ecosystem services are common but the drivers of these relationships are poorly understood. To guide management that seeks to promote multiple services, we investigated the relationships between 12 stand-level forest attributes, including structure, composition, heterogeneity and plant diversity, plus 4 environmental factors, and proxies for 14 ecosystem services in 150 temperate forest plots. Our results show that forest attributes are the best predictors of most ecosystem services and are also good predictors of several synergies and trade-offs between services. Environmental factors also play an important role, mostly in combination with forest attributes. Our study suggests that managing forests to increase structural heterogeneity, maintain large trees, and canopy gaps would promote the supply of multiple ecosystem services. These results highlight the potential for forest management to encourage multifunctional forests and suggest that a coordinated landscape-scale strategy could help to mitigate trade-offs in human-dominated landscapes.


Assuntos
Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Florestas , Árvores/fisiologia , Ecossistema , Europa (Continente) , Agricultura Florestal/tendências , Humanos
13.
Environ Monit Assess ; 190(12): 714, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30417241

RESUMO

Shifts in government priorities in response to the 2007 global recession have affected wildfire management and natural disaster funding arrangements, leading to a reduced effectiveness of fire suppression actions and increasing fire vulnerability. Our study investigates the role of local socioeconomic contexts on fire suppression effectiveness under economic expansion and recession in a Mediterranean region (Attica, Greece) strongly affected by 2007 crisis and displaying a persistently high density of peri-urban wildfires. Basic characteristics of wildfires (spatial distribution, intensity, and land use preferences) were investigated in the study area over two consecutive 8-year time intervals characterized by economic expansion (2000-2007) and recession (2008-2015). An integrated approach based on multivariate statistics and artificial neural networks was implemented to evaluate latent relationships between fire suppression time, wildfire characteristics, and socioeconomic dynamics. Controlling for wildfires' characteristics over the two time intervals, fire time length increased under crisis-mainly for small and medium-sized fires-possibly as an indirect response to reduced effectiveness of forest land management. Local contexts and political decisions influenced by economic downturns are relevant factors shaping wildfires' severity in the Mediterranean region. With recession, local contexts vulnerable to wildfires require more effective fire prevention measures, sustainable forest management, and regional planning.


Assuntos
Monitoramento Ambiental , Incêndios Florestais , Agricultura Florestal/métodos , Agricultura Florestal/tendências , Florestas , Grécia , Região do Mediterrâneo , Análise Multivariada , Redes Neurais de Computação , Fatores Socioeconômicos , Fatores de Tempo
15.
Environ Manage ; 62(6): 1108-1133, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30128584

RESUMO

The role of digital technologies for fostering sustainability and efficiency in forest-based supply chains is well acknowledged and motivated several studies in the scope of precision forestry. Sensor technologies can collect relevant data in forest-based supply chains, comprising all activities from within forests and the production of the woody raw material to its transformation into marketable forest-based products. Advanced planning systems can help to support decisions of the various entities in the supply chain, e.g., forest owners, harvest companies, haulage companies, and forest product processing industry. Such tools can help to deal with the complex interdependencies between different entities, often with opposing objectives and actions-which may increase efficiency of forest-based supply chains. This paper analyzes contemporary literature dealing with digital technologies in forest-based supply chains and summarizes the state-of-the-art digital technologies for real-time data collection on forests, product flows, and forest operations, as well as planning systems and other decision support systems in use by supply chain actors. Higher sustainability and efficiency of forest-based supply chains require a seamless information flow to foster integrated planning of the activities over the supply chain-thereby facilitating seamless data exchange between the supply chain entities and foster new forms of collaboration. Therefore, this paper deals with data exchange and multi-entity collaboration aspects in combination with interoperability challenges related with the integration among multiple process data collection tools and advanced planning systems. Finally, this interdisciplinary review leads to the discussion of relevant guidelines that can guide future research and integration projects in this domain.


Assuntos
Agricultura Florestal/tendências , Tomada de Decisões , Agricultura Florestal/métodos , Florestas , Tecnologia , Madeira/química
16.
Nature ; 560(7720): 639-643, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089903

RESUMO

Land change is a cause and consequence of global environmental change1,2. Changes in land use and land cover considerably alter the Earth's energy balance and biogeochemical cycles, which contributes to climate change and-in turn-affects land surface properties and the provision of ecosystem services1-4. However, quantification of global land change is lacking. Here we analyse 35 years' worth of satellite data and provide a comprehensive record of global land-change dynamics during the period 1982-2016. We show that-contrary to the prevailing view that forest area has declined globally5-tree cover has increased by 2.24 million km2 (+7.1% relative to the 1982 level). This overall net gain is the result of a net loss in the tropics being outweighed by a net gain in the extratropics. Global bare ground cover has decreased by 1.16 million km2 (-3.1%), most notably in agricultural regions in Asia. Of all land changes, 60% are associated with direct human activities and 40% with indirect drivers such as climate change. Land-use change exhibits regional dominance, including tropical deforestation and agricultural expansion, temperate reforestation or afforestation, cropland intensification and urbanization. Consistently across all climate domains, montane systems have gained tree cover and many arid and semi-arid ecosystems have lost vegetation cover. The mapped land changes and the driver attributions reflect a human-dominated Earth system. The dataset we developed may be used to improve the modelling of land-use changes, biogeochemical cycles and vegetation-climate interactions to advance our understanding of global environmental change1-4,6.


Assuntos
Planeta Terra , Ecossistema , Monitoramento Ambiental , Atividades Humanas/estatística & dados numéricos , Agricultura/estatística & dados numéricos , Agricultura/tendências , Mudança Climática/estatística & dados numéricos , Agricultura Florestal/estatística & dados numéricos , Agricultura Florestal/tendências , Atividades Humanas/tendências , Imagens de Satélites , Árvores/crescimento & desenvolvimento
18.
Environ Manage ; 62(1): 45-57, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29785612

RESUMO

A growing world population and rapid expansion of cities increase the pressure on basic resources such as water, food and energy. To safeguard the provision of these resources, restoration and sustainable management of landscapes is pivotal, including sustainable forest and water management. Sustainable forest management includes forest conservation, restoration, forestry and agroforestry practices. Interlinkages between forests and water are fundamental to moderate water budgets, stabilize runoff, reduce erosion and improve biodiversity and water quality. Sweden has gained substantial experience in sustainable forest management in the past century. Through significant restoration efforts, a largely depleted Swedish forest has transformed into a well-managed production forest within a century, leading to sustainable economic growth through the provision of forest products. More recently, ecosystem services are also included in management decisions. Such a transformation depends on broad stakeholder dialog, combined with an enabling institutional and policy environment. Based on seminars and workshops with a wide range of key stakeholders managing Sweden's forests and waters, this article draws lessons from the history of forest management in Sweden. These lessons are particularly relevant for countries in the Global South that currently experience similar challenges in forest and landscape management. The authors argue that an integrated landscape approach involving a broad array of sectors and stakeholders is needed to achieve sustainable forest and water management. Sustainable landscape management-integrating water, agriculture and forests-is imperative to achieving resilient socio-economic systems and landscapes.


Assuntos
Conservação dos Recursos Naturais/métodos , Política Ambiental/tendências , Agricultura Florestal/organização & administração , Florestas , Árvores/crescimento & desenvolvimento , Qualidade da Água/normas , Agricultura/organização & administração , Biodiversidade , Agricultura Florestal/tendências , Crescimento Demográfico , Suécia , Árvores/classificação , Urbanização
19.
Environ Manage ; 62(1): 15-28, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29520438

RESUMO

In parts of the developing world, deforestation rates are high and poverty is chronic and pervasive. Addressing these issues through the commercialization of non-timber forest products (NTFPs) has been widely researched, tested, and discussed. While the evidence is inconclusive, there is growing understanding of what works and why, and this paper examines the acknowledged success and failure factors. African forest honey has been relatively overlooked as an NTFP, an oversight this paper addresses. Drawing on evidence from a long-established forest conservation, livelihoods, and trade development initiative in SW Ethiopia, forest honey is benchmarked against accepted success and failure factors and is found to be a near-perfect NTFP. The criteria are primarily focused on livelihood impacts and consequently this paper makes recommendations for additional criteria directly related to forest maintenance.


Assuntos
Criação de Abelhas/economia , Conservação dos Recursos Naturais/economia , Agricultura Florestal/economia , Florestas , Mel/economia , Criação de Abelhas/métodos , Criação de Abelhas/tendências , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Etiópia , Agricultura Florestal/métodos , Agricultura Florestal/tendências , Humanos , Árvores/crescimento & desenvolvimento
20.
PLoS One ; 13(1): e0190003, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29320520

RESUMO

Tropical montane habitats, grasslands, in particular, merit urgent conservation attention owing to the disproportionate levels of endemic biodiversity they harbour, the ecosystem services they provide, and the fact that they are among the most threatened habitats globally. The Shola Sky Islands in the Western Ghats host a matrix of native forest-grassland matrix that has been planted over the last century, with exotic timber plantations. The popular discourse on the landscape change is that mainly forests have been lost to the timber plantations and recent court directives are to restore Shola forest trees. In this study, we examine spatiotemporal patterns of landscape change over the last 40 years in the Palani Hills, a significant part of the montane habitat in the Western Ghats. Using satellite imagery and field surveys, we find that 66% of native grasslands and 31% of native forests have been lost over the last 40 years. Grasslands have gone from being the dominant, most contiguous land cover to one of the rarest and most fragmented. They have been replaced by timber plantations and, to a lesser extent, expanding agriculture. We find that the spatial pattern of grassland loss to plantations differs from the loss to agriculture, likely driven by the invasion of plantation species into grasslands. We identify remnant grasslands that should be prioritised for conservation and make specific recommendations for conservation and restoration of grasslands in light of current management policy in the Palani Hills, which favours large-scale removal of plantations and emphasises the restoration of native forests.


Assuntos
Agricultura , Conservação dos Recursos Naturais , Agricultura Florestal , Pradaria , Agricultura/tendências , Área Sob a Curva , Ecossistema , Agricultura Florestal/tendências , Atividades Humanas , Lagos , Modelos Teóricos , Curva ROC , Imagens de Satélites , Sri Lanka , Árvores
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