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1.
Environ Manage ; 73(2): 395-407, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37796334

RESUMO

Promoting the diversity of biological communities in areas of agricultural production is a very current debate since protected areas may not be sufficient to ensure biodiversity conservation. Among the biological communities affected by the production areas are birds, which show rapid responses to changes in the landscape. Here we seek to understand how landscape planning, concerning its composition and configuration, in areas with a matrix of planted Eucalyptus spp. forests influences the functional diversity of bird assemblages in the Atlantic Forest. Our results show that the spatial distribution design of planted forests in terms of age, land cover and clone types have effects on bird diversity with regard to functional divergence, functional evenness and species richness. These results reinforce the importance of good management for the maintenance of bird diversity. We found that bird functional diversity in planted forest matrices increased with the proximity index, proportion of native vegetation and age importance value, and is negatively influenced by edge density and proportion of forest plantation. For bird conservation, it is thus better to associate Eucalyptus spp. with other cover types in the landscape. These results corroborate that, to increase bird functional diversity, it is possible to associate conservation and production in the same landscape. Mosaic landscapes have great potential to contribute to the conservation of bird biodiversity outside protected areas. However, decisions regarding the management of planted forests and planning of improved areas intended for conservation seem to be decisive to ensure the maintenance of bird biodiversity.


Assuntos
Eucalyptus , Animais , Florestas , Biodiversidade , Biota , Aves/fisiologia , Ecossistema
2.
Biota Neotrop. (Online, Ed. ingl.) ; 24(2): e20231569, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564051

RESUMO

Abstract The Atlantic Forest and Cerrado (Brazilian Savannah) contain a large number of endemic species and high species diversity, particularly for medium and large-bodied mammals. However, there is no large-scale assessment of these animals and their spatial distribution. Our study synthesises the literature on medium and large-bodied mammal surveys in the Cerrado and Atlantic Forest to provide insights into their distributions across large spatial scales and identify knowledge gaps to guide future research. We synthesised papers published in three databases, focusing on mammals weighing more than 1kg. Of the 84 papers we found, the majority (57.14%) were on mammals in the Atlantic Forest, while 42.85% were on mammals found in the Cerrado. We gathered records for 116 species, the most common of which were Cerdocyon thous (Linnaeus, 1766), Procyon cancrivorus (Cuvier, 1798) and Chrysocyon brachyurus (Illiger, 1815) (Cerrado); Dasypus novemcinctus (Linnaeus, 1758), Cerdocyon thous (Linnaeus, 1766) and Nasua nasua (Linnaeus, 1766; Atlantic Forest). Our study allowed us to access, for the first time in the Atlantic Forest and Cerrado, the information available about medium and large-bodied mammals. We also highlight important sampling gaps, especially concerning the northern parts of both biomes that we need to address, as well as the differences in density of sampling points that are caused by a smaller concentration of sampling efforts in the Atlantic Forest than what we found in Cerrado. As a consequence, larger extensions of Cerrado present knowledge gaps concerning mammal surveys that need to be investigated in future research.


Resumo A Mata Atlântica e o Cerrado brasileiro abrigam uma enorme quantidade de espécies endêmicas e alta diversidade de espécies, especialmente de mamíferos de médio e grande porte. No entanto, não há uma avaliação em larga escala desses animais e de sua distribuição espacial. Nosso estudo sintetiza a literatura sobre levantamentos de mamíferos de médio e grande porte no Cerrado e na Mata Atlântica, com o objetivo de fornecer informações sobre suas distribuições em larga escala e identificar lacunas no conhecimento para guiar futuras pesquisas. Sintetizamos artigos publicados em três bases de dados, com foco em mamíferos com peso superior a 1 kg. Dos 84 artigos encontrados, a maioria (57,14%) tratava de mamíferos na Mata Atlântica, enquanto 42,85% abordavam mamíferos encontrados no Cerrado. Coletamos registros para 116 espécies, sendo as mais comuns Cerdocyon thous (Linnaeus, 1766), Procyon cancrivorus (Cuvier, 1798) e Chrysocyon brachyurus (Illiger, 1815) (Cerrado); Dasypus novemcinctus (Linnaeus, 1758), Cerdocyon thous (Linnaeus, 1766) e Nasua nasua (Linnaeus, 1766; Mata Atlântica). Nosso estudo também mostra as lacunas no levantamento especialmente em relação às distribuições ao norte dos biomas, que precisam ser resolvidas, assim como a diferença na densidade de pontos que é causada pela menor concentração de amostragens na Mata Atlântica do que o que encontramos no Cerrado. Como consequência, existem largas extensões do Cerrado que apresentam lacunas no levantamento de mamíferos que precisam ser investigados em pesquisas futuras.

4.
J Environ Manage ; 343: 118256, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37247542

RESUMO

Although a growing body of literature recognises the importance of rarity for biodiversity conservation, it is unclear how the interaction of different forms of rarity, extrinsic causes of extinction, and protection affect species' vulnerability. Here we addressed the extinction vulnerability of 2203 shrub and tree species of the South American savanna (SAS). For this, species were attributed a form of rarity, a synergistic risk index (SRI), and a protection index (PI). The SRI combines three extrinsic causes of extinction (climate hazard, fire frequency, and human footprint). The PI is the ratio between the number of a species occurrences within protected areas and the total number of occurrences in the SAS. By combining the SRI and PI, we classified common and rare species into five vulnerability classes. Some regions of the SAS show high values of climate hazard, fire frequency, human footprint, and SRI. Each extrinsic cause of extinction is differently distributed across the SAS and shows no or low spatial congruence with the SRI. Many species show a low ratio of occurrences within PAs, which in combination with high SRI results in high vulnerability to extinction. Surprisingly, the number of common species in the higher vulnerability classes is higher than of rare species. Common and rare species in different vulnerability classes occur in somewhat different locations across the SAS and mainly constitute spatially incongruent centres with high species richness. Given our results, we propose that strategies for the effective conservation of SAS species are challenging and must be carefully designed.


Assuntos
Conservação dos Recursos Naturais , Árvores , Humanos , Pradaria , Biodiversidade , América do Sul , Ecossistema , Extinção Biológica
7.
PeerJ ; 11: e14027, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643651

RESUMO

The genus Radiodiscus includes minute terrestrial snails occurring throughout the American continent. We assessed the conservation status of eight poorly known Chilean Radiodiscus species using the International Union for Conservation of Nature (IUCN) and NatureServe categories and criteria. Under the IUCN guidelines the species were assessed using the Criterion B of geographic range, which considers the extent of occurrence (EOO) and area of occupancy (AOO) as subcriteria. For NatureServe we used these two parameters plus the number of occurrences, ecological viability, and threats. Considering species rarity and possible sampling bias, we also used ecological niche modeling to determine climate and environmental tolerances and predict potential species distributions analyzing bioclimatic and geographical layers. Radiodiscus australis, R. coarctatus and R. quillajicola were listed as Critically Endangered by IUCN and NatureServe standards; R. coppingeri, R. flammulatus, R. magellanicus and R. villarricensis as Endangered by both methods; while R. riochicoensis as Endangered by IUCN standards and Vulnerable by NatureServe standards. Niche modeling results indicated that Radiodiscus species respond to different environmental conditions and that the predicted distribution areas contain suitable habitats beyond the current ranges, which may be helpful for future management plans. Nature-based sport tourism, forestry activities, urbanization, roads, pollution, mining, forest fires, livestock, volcanism, tsunamis, soil erosion and introduced species are among the major threats affecting these snails. Based on the low number of occurrences and the threats identified, the most at-risk species are R. coarctatus and R. quillajicola (one record), R. australis (two records) and R. villarricensis (three records); the latter two lacking occurrences within protected areas. Compiling our findings, we propose a list of actions to preserve Chilean Radiodiscus species.


Assuntos
Espécies em Perigo de Extinção , Gastrópodes , Animais , Extinção Biológica , Chile , Ecossistema
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