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1.
Sci Rep ; 14(1): 4722, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413813

RESUMO

In an increasingly human- and road-dominated world, the preservation of functional ecosystems has become highly relevant. While the negative ecological impacts of roads on ecosystems are numerous and well documented, roadless areas have been proposed as proxy for functional ecosystems. However, their potential remains underexplored, partly due to the incomplete mapping of roads. We assessed the accuracy of roadless areas identification using freely available road-data in two regions with contrasting levels of anthropogenic influence: boreal Canada and temperate Central Europe (Poland, Slovakia, Czechia, and Hungary). Within randomly selected circular plots (per region and country), we visually examined the completeness of road mapping using OpenStreetMap 2020 and assessed whether human influences affect mapping quality using four variables. In boreal Canada, roads were completely mapped in 3% of the plots, compared to 40% in Central Europe. Lower Human Footprint Index and road density values were related to greater incompleteness in road mapping. Roadless areas, defined as areas at least 1 km away from any road, covered 85% of the surface in boreal Canada (mean size ± s.d. = 272 ± 12,197 km2), compared to only 0.4% in temperate Central Europe (mean size ± s.d. = 0.6 ± 3.1 km2). By visually interpreting and manually adding unmapped roads in 30 randomly selected roadless areas from each study country, we observed a similar reduction in roadless surface in both Canada and Central Europe (27% vs 28%) when all roads were included. This study highlights the urgent need for improved road mapping techniques to support research on roadless areas as conservation targets and surrogates of functional ecosystems.


Assuntos
Ecossistema , Humanos , Europa (Continente) , Canadá , Polônia , Hungria
2.
Science ; 382(6676): 1253-1254, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38096274
3.
Nat Ecol Evol ; 6(10): 1423-1437, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35941205

RESUMO

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers.


Assuntos
Biodiversidade , Florestas , Solo , Árvores
5.
Sci Data ; 8(1): 220, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404811

RESUMO

Primary forests, defined here as forests where the signs of human impacts, if any, are strongly blurred due to decades without forest management, are scarce in Europe and continue to disappear. Despite these losses, we know little about where these forests occur. Here, we present a comprehensive geodatabase and map of Europe's known primary forests. Our geodatabase harmonizes 48 different, mostly field-based datasets of primary forests, and contains 18,411 individual patches (41.1 Mha) spread across 33 countries. When available, we provide information on each patch (name, location, naturalness, extent and dominant tree species) and the surrounding landscape (biogeographical regions, protection status, potential natural vegetation, current forest extent). Using Landsat satellite-image time series (1985-2018) we checked each patch for possible disturbance events since primary forests were identified, resulting in 94% of patches free of significant disturbances in the last 30 years. Although knowledge gaps remain, ours is the most comprehensive dataset on primary forests in Europe, and will be useful for ecological studies, and conservation planning to safeguard these unique forests.


Assuntos
Conservação dos Recursos Naturais , Florestas , Bases de Dados Factuais , Europa (Continente)
8.
PLoS One ; 14(7): e0219408, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31339902

RESUMO

The island of New Guinea hosts the third largest expanse of tropical rainforest on the planet. Papua New Guinea-comprising the eastern half of the island-plans to nearly double its national road network (from 8,700 to 15,000 km) over the next three years, to spur economic growth. We assessed these plans using fine-scale biophysical and environmental data. We identified numerous environmental and socioeconomic risks associated with these projects, including the dissection of 54 critical biodiversity habitats and diminished forest connectivity across large expanses of the island. Key habitats of globally endangered species including Goodfellow's tree-kangaroo (Dendrolagus goodfellowi), Matchie's tree kangaroo (D. matschiei), and several birds of paradise would also be bisected by roads and opened up to logging, hunting, and habitat conversion. Many planned roads would traverse rainforests and carbon-rich peatlands, contradicting Papua New Guinea's international commitments to promote low-carbon development and forest conservation for climate-change mitigation. Planned roads would also create new deforestation hotspots via rapid expansion of logging, mining, and oil-palm plantations. Our study suggests that several planned road segments in steep and high-rainfall terrain would be extremely expensive in terms of construction and maintenance costs. This would create unanticipated economic challenges and public debt. The net environmental, social, and economic risks of several planned projects-such as the Epo-Kikori link, Madang-Baiyer link, Wau-Malalaua link, and some other planned projects in the Western and East Sepik Provinces-could easily outstrip their overall benefits. Such projects should be reconsidered under broader environmental, economic, and social grounds, rather than short-term economic considerations.


Assuntos
Desenvolvimento Sustentável , Biodiversidade , Conservação dos Recursos Naturais , Florestas , Geografia , Papua Nova Guiné , Chuva , Risco
9.
Environ Manage ; 62(5): 858-876, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30120499

RESUMO

Growing levels of uncertainty and vulnerability generated by land use conversion and climate change set demands on local communities and national institutions to build synergies between the diverse array of knowledge systems in order to provide policy makers and practitioners with the best available information to decide what urgent actions must be taken. Science policy arenas and agreements such as the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) and the Convention on Biological Diversity (CBD) recognize the importance of different types of knowledge and the need for broad stakeholder involvement, yet the use of indigenous and local knowledge (ILK) in environmental decision-making processes is still underdeveloped. This study involved working with local stakeholders, using the MARISCO method (adaptive MAnagement of vulnerability and RISks at COnservation sites) to carry out a systematic situation analysis of the existing socioenvironmental conditions. The assessments were conducted in the Kavango East Region in northern Namibia with the participation of inhabitants of the Khaudum North Complex, a protected area network covering wooded savannahs belonging to the Northern Kalahari sandveld. General outcomes of the assessments and evaluations made by the local stakeholders concerning the most critical drivers of degradation of the ecosystems appeared to support existing scientific knowledge of the study area, demonstrating that community-based assessments can provide valuable information about socioecological systems where scientific data are scarce. The findings of this study also highlight the importance of power dynamics for the implementation of participatory processes and the interpretation of their outcomes.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Agricultura Florestal/economia , Setor Privado/economia , Desenvolvimento Sustentável/economia , Biodiversidade , Botsuana , Mudança Climática , Conservação dos Recursos Naturais/economia , Conhecimento , Namíbia
10.
PLoS One ; 12(10): e0185972, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28982187

RESUMO

Protected areas are arguably the most important instrument of biodiversity conservation. To keep them fit under climate change, their management needs to be adapted to address related direct and indirect changes. In our study we focus on the adaptation of conservation management planning, evaluating management plans of 60 protected areas throughout Germany with regard to their climate change-robustness. First, climate change-robust conservation management was defined using 11 principles and 44 criteria, which followed an approach similar to sustainability standards. We then evaluated the performance of individual management plans concerning the climate change-robustness framework. We found that climate change-robustness of protected areas hardly exceeded 50 percent of the potential performance, with most plans ranking in the lower quarter. Most Natura 2000 protected areas, established under conservation legislation of the European Union, belong to the sites with especially poor performance, with lower values in smaller areas. In general, the individual principles showed very different rates of accordance with our principles, but similarly low intensity. Principles with generally higher performance values included holistic knowledge management, public accountability and acceptance as well as systemic and strategic coherence. Deficiencies were connected to dealing with the future and uncertainty. Lastly, we recommended the presented principles and criteria as essential guideposts that can be used as a checklist for working towards more climate change-robust planning.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Alemanha
11.
Science ; 356(6337): 496, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28473556
12.
Science ; 355(6332): 1382, 2017 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-28360290
13.
Science ; 354(6318): 1423-1427, 2016 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-27980208

RESUMO

Roads fragment landscapes and trigger human colonization and degradation of ecosystems, to the detriment of biodiversity and ecosystem functions. The planet's remaining large and ecologically important tracts of roadless areas sustain key refugia for biodiversity and provide globally relevant ecosystem services. Applying a 1-kilometer buffer to all roads, we present a global map of roadless areas and an assessment of their status, quality, and extent of coverage by protected areas. About 80% of Earth's terrestrial surface remains roadless, but this area is fragmented into ~600,000 patches, more than half of which are <1 square kilometer and only 7% of which are larger than 100 square kilometers. Global protection of ecologically valuable roadless areas is inadequate. International recognition and protection of roadless areas is urgently needed to halt their continued loss.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Mapeamento Geográfico
14.
Conserv Biol ; 29(1): 260-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25103194

RESUMO

Established under the European Union (EU) Birds and Habitats Directives, Natura 2000 is one of the largest international networks of protected areas. With the spatial designation of sites by the EU member states almost finalized, the biggest challenge still lying ahead is the appropriate management of the sites. To evaluate the cross-scale functioning of Natura 2000 implementation, we analyzed 242 questionnaires completed by conservation scientists involved in the implementation of Natura 2000 in 24 EU member states. Respondents identified 7 key drivers of the quality of Natura 2000 implementation. Ordered in decreasing evaluation score, these drivers included: network design, use of external resources, legal frame, scientific input, procedural frame, social input, and national or local policy. Overall, conservation scientists were moderately satisfied with the implementation of Natura 2000. Tree modeling revealed that poor application of results of environmental impact assessments (EIA) was considered a major constraint. The main strengths of the network included the substantial increase of scientific knowledge of the sites, the contribution of nongovernmental organizations, the adequate network design in terms of area and representativeness, and the adequacy of the EU legal frame. The main weaknesses of Natura 2000 were the lack of political will from local and national governments toward effective implementation; the negative attitude of local stakeholders; the lack of background knowledge of local stakeholders, which prevented well-informed policy decisions; and the understaffing of Natura 2000 management authorities. Top suggestions to improve Natura 2000 implementation were increase public awareness, provide environmental education to local communities, involve high-quality conservation experts, strengthen quality control of EIA studies, and establish a specific Natura 2000 fund.


Assuntos
Conservação dos Recursos Naturais , União Europeia , Biodiversidade , Conservação dos Recursos Naturais/legislação & jurisprudência , Ecossistema , Inquéritos e Questionários
15.
Environ Manage ; 48(5): 865-77, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21947368

RESUMO

With increasing road encroachment, habitat fragmentation by transport infrastructures has been a serious threat for European biodiversity. Areas with no roads or little traffic ("roadless and low-traffic areas") represent relatively undisturbed natural habitats and functioning ecosystems. They provide many benefits for biodiversity and human societies (e.g., landscape connectivity, barrier against pests and invasions, ecosystem services). Roadless and low-traffic areas, with a lower level of anthropogenic disturbances, are of special relevance in Europe because of their rarity and, in the context of climate change, because of their contribution to higher resilience and buffering capacity within landscape ecosystems. An analysis of European legal instruments illustrates that, although most laws aimed at protecting targets which are inherent to fragmentation, like connectivity, ecosystem processes or integrity, roadless areas are widely neglected as a legal target. A case study in Germany underlines this finding. Although the Natura 2000 network covers a significant proportion of the country (16%), Natura 2000 sites are highly fragmented and most low-traffic areas (75%) lie unprotected outside this network. This proportion is even higher for the old Federal States (western Germany), where only 20% of the low-traffic areas are protected. We propose that the few remaining roadless and low-traffic areas in Europe should be an important focus of conservation efforts; they should be urgently inventoried, included more explicitly in the law and accounted for in transport and urban planning. Considering them as complementary conservation targets would represent a concrete step towards the strengthening and adaptation of the Natura 2000 network to climate change.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Meios de Transporte , Reforma Urbana/métodos , Mudança Climática , Conservação dos Recursos Naturais/legislação & jurisprudência , Europa (Continente) , Humanos , Política Pública , Reforma Urbana/legislação & jurisprudência
16.
BMC Ecol ; 11: 12, 2011 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-21539736

RESUMO

BACKGROUND: Protected areas are the most common and important instrument for the conservation of biological diversity and are called for under the United Nations' Convention on Biological Diversity. Growing human population densities, intensified land-use, invasive species and increasing habitat fragmentation threaten ecosystems worldwide and protected areas are often the only refuge for endangered species. Climate change is posing an additional threat that may also impact ecosystems currently under protection. Therefore, it is of crucial importance to include the potential impact of climate change when designing future nature conservation strategies and implementing protected area management. This approach would go beyond reactive crisis management and, by necessity, would include anticipatory risk assessments. One avenue for doing so is being provided by simulation models that take advantage of the increase in computing capacity and performance that has occurred over the last two decades.Here we review the literature to determine the state-of-the-art in modeling terrestrial protected areas under climate change, with the aim of evaluating and detecting trends and gaps in the current approaches being employed, as well as to provide a useful overview and guidelines for future research. RESULTS: Most studies apply statistical, bioclimatic envelope models and focus primarily on plant species as compared to other taxa. Very few studies utilize a mechanistic, process-based approach and none examine biotic interactions like predation and competition. Important factors like land-use, habitat fragmentation, invasion and dispersal are rarely incorporated, restricting the informative value of the resulting predictions considerably. CONCLUSION: The general impression that emerges is that biodiversity conservation in protected areas could benefit from the application of modern modeling approaches to a greater extent than is currently reflected in the scientific literature. It is particularly true that existing models have been underutilized in testing different management options under climate change. Based on these findings we suggest a strategic framework for more effectively incorporating the impact of climate change in models exploring the effectiveness of protected areas.


Assuntos
Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Modelos Biológicos , Animais , Ecossistema , Atividades Humanas , Humanos
17.
Conserv Biol ; 25(4): 708-15, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21488958

RESUMO

Conservation actions need to account for and be adapted to address changes that will occur under global climate change. The identification of stresses on biological diversity (as defined in the Convention on Biological Diversity) is key in the process of adaptive conservation management. We considered any impact of climate change on biological diversity a stress because such an effect represents a change (negative or positive) in key ecological attributes of an ecosystem or parts of it. We applied a systemic approach and a hierarchical framework in a comprehensive classification of stresses to biological diversity that are caused directly by global climate change. Through analyses of 20 conservation sites in 7 countries and a review of the literature, we identified climate-change-induced stresses. We grouped the identified stresses according to 3 levels of biological diversity: stresses that affect individuals and populations, stresses that affect biological communities, and stresses that affect ecosystem structure and function. For each stress category, we differentiated 3 hierarchical levels of stress: stress class (thematic grouping with the coarsest resolution, 8); general stresses (thematic groups of specific stresses, 21); and specific stresses (most detailed definition of stresses, 90). We also compiled an overview of effects of climate change on ecosystem services using the categories of the Millennium Ecosystem Assessment and 2 additional categories. Our classification may be used to identify key climate-change-related stresses to biological diversity and may assist in the development of appropriate conservation strategies. The classification is in list format, but it accounts for relations among climate-change-induced stresses.


Assuntos
Biodiversidade , Mudança Climática , Estresse Fisiológico , Animais , Conservação dos Recursos Naturais , Ecossistema , Modelos Teóricos
18.
Proc Natl Acad Sci U S A ; 106(23): 9322-7, 2009 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-19470638

RESUMO

Endemism and species richness are highly relevant to the global prioritization of conservation efforts in which oceanic islands have remained relatively neglected. When compared to mainland areas, oceanic islands in general are known for their high percentage of endemic species but only moderate levels of species richness, prompting the question of their relative conservation value. Here we quantify geographic patterns of endemism-scaled richness ("endemism richness") of vascular plants across 90 terrestrial biogeographic regions, including islands, worldwide and evaluate their congruence with terrestrial vertebrates. Endemism richness of plants and vertebrates is strongly related, and values on islands exceed those of mainland regions by a factor of 9.5 and 8.1 for plants and vertebrates, respectively. Comparisons of different measures of past and future human impact and land cover change further reveal marked differences between mainland and island regions. While island and mainland regions suffered equally from past habitat loss, we find the human impact index, a measure of current threat, to be significantly higher on islands. Projected land-cover changes for the year 2100 indicate that land-use-driven changes on islands might strongly increase in the future. Given their conservation risks, smaller land areas, and high levels of endemism richness, islands may offer particularly high returns for species conservation efforts and therefore warrant a high priority in global biodiversity conservation in this century.


Assuntos
Biodiversidade , Plantas/classificação , Vertebrados/classificação , Animais , Conservação dos Recursos Naturais , Ecossistema , Geografia , Humanos
19.
Mol Phylogenet Evol ; 51(3): 472-85, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19171196

RESUMO

The about 31 species of Fosterella L.B. Sm. (Bromeliaceae) are terrestrial herbs with a centre of diversity in the central South American Andes. To resolve infra- and intergeneric relationships among Fosterella and their putative allies, we conducted a phylogenetic analysis based on sequence data from four chloroplast DNA regions (matK gene, rps16 intron, atpB-rbcL and psbB-psbH intergenic spacers). Sequences were generated for 96 accessions corresponding to 60 species from 18 genera. Among these, 57 accessions represented 22 of the 31 recognized Fosterella species and one undescribed morphospecies. Maximum parsimony and Bayesian inference methods yielded well-resolved phylogenies. The monophyly of Fosterella was strongly supported, as was its sister relationship with a clade comprising Deuterocohnia, Dyckia and Encholirium. Six distinct evolutionary lineages were distinguished within Fosterella. Character mapping indicated that parallel evolution of identical character states is common in the genus. Relationships between species and lineages are discussed in the context of morphological, ecological and biogeographical data as well as the results of a previous amplified fragment length polymorphism (AFLP) study.


Assuntos
Bromeliaceae/genética , DNA de Cloroplastos/genética , Evolução Molecular , Filogenia , Bromeliaceae/classificação , DNA de Plantas/genética , Genes de Plantas , Alinhamento de Sequência , Análise de Sequência de DNA
20.
Genome ; 50(1): 90-105, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17546075

RESUMO

The neotropical genus Fosterella L.B. Smith (Pitcairnioideae, Bromeliaceae) comprises about 30 species, with a centre of diversity in semiarid to humid habitats of the Andean slopes and valleys of Bolivia. Morphologic differentiation of species is difficult because of a paucity of diagnostic characters, and little is known about the infrageneric phylogeny. Here, we present the results of an amplified fragment length polymorphism (AFLP) analysis of 77 Fosterella specimens, covering 18 recognized species and 9 as-yet undescribed morphospecies. Eight primer combinations produced 310 bands, which were scored as presence/absence characters. Neighbour-joining tree reconstruction revealed 12 clusters (A-L) with various levels of support. Well-supported species groups were also recovered by a principal coordinates analysis. With few exceptions, morphologically defined species boundaries were confirmed by the molecular data. Phylogenetic relationships between species groups remained ambiguous, however, because of short internal branch lengths. The AFLP data were complemented by a survey of the leaf anatomy of 19 Fosterella species. Species concepts and assemblages are discussed in the context of molecular, morphologic, anatomic, ecologic, and biogeographic data. The data suggest that accidental long-distance dispersal and founder events have been important for Fosterella speciation.


Assuntos
Bromeliaceae/classificação , Bromeliaceae/genética , Polimorfismo Genético , Bandeamento Cromossômico , Cromossomos de Plantas/genética , DNA de Plantas/genética , Geografia , Filogenia , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico
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