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1.
Dermatol Ther (Heidelb) ; 14(3): 729-743, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38451423

RESUMO

INTRODUCTION: Secukinumab is an anti-interleukin (IL)-17A monoclonal antibody indicated for multiple immunological disorders. Here, we aim to summarize secukinumab safety in clinical trials (CTs) and post-marketing setting (PMS) until 25 June 2022. METHODS: Adverse events (AEs) were summarized with crude reporting rate (RR) per 100 patient-years (PY) in PMS for all reported indications and with exposure-adjusted incident rates (EAIR) per 100 PY in pooled 47 CTs for approved indications. RESULTS: Secukinumab exposure totaled 1,159,260 PY in PMS and 27,765 PY in CTs. AEs were mostly (> 80%) non-serious in PMS. EAIR for serious AEs was 7.0/100 PY. Nasopharyngitis (RR 0.59/100 PY, EAIR 16.08/100 PY) and pneumonia (RR 0.14/100 PY, EAIR 0.17/100 PY) were the most common infection and serious infection, respectively. Candida infections (RR 0.20/100 PY, EAIR 2.16/100 PY) were the most common fungal infections. Inflammatory bowel disease (IBD) was observed in PMS (0.14/100 PY) and CTs (0.26/100 PY). Most (76%) patients with prior IBD did not report IBD flare during CTs. PMS monitoring identified paradoxical skin reactions including dyshidrotic eczema (RR 0.006/100 PY) and pyoderma gangrenosum (RR 0.003/100 PY). CONCLUSION: Secukinumab safety profile with increased patient exposure remained favorable. Paradoxical skin reactions were identified in post-marketing monitoring.

3.
Sci Rep ; 13(1): 14474, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660141

RESUMO

Stingless bees are major flower visitors in the tropics, but their foraging preferences and behavior are still poorly understood. Studying stingless bee interactions with angiosperms is methodologically challenging due to the high tropical plant diversity and inaccessibility of upper canopy flowers in forested habitats. Pollen DNA metabarcoding offers an opportunity of assessing floral visitation efficiently and was applied here to understand stingless bee floral resources spectra and foraging behavior. We analyzed pollen and honey from nests of three distantly related stingless bee species, with different body size and social behavior: Melipona rufiventris, Scaptotrigona postica and Tetragonisca angustula. Simultaneously, we evaluate the local floristic components through seventeen rapid botanical surveys conducted at different distances from the nests. We discovered a broad set of explored floral sources, with 46.3 plant species per bee species in honey samples and 53.67 in pollen samples. Plant families Myrtaceae, Asteraceae, Euphorbiaceae, Melastomataceae and Malpighiaceae dominated the records, indicating stingless bee preferences for abundant resources that flowers of these families provide in the region. Results also reinforce the preference of stingless bees for forest trees, even if only available at long distances. Our high-resolution results encourage future bee-plant studies using pollen and honey metabarcoding in hyper-diverse tropical environments.


Assuntos
Asteraceae , Mel , Abelhas , Animais , Pólen , Comportamento Social , Tamanho Corporal
4.
Glob Chang Biol ; 29(17): 4880-4897, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37365752

RESUMO

Tropical and subtropical dry woodlands are rich in biodiversity and carbon. Yet, many of these woodlands are under high deforestation pressure and remain weakly protected. Here, we assessed how deforestation dynamics relate to areas of woodland protection and to conservation priorities across the world's tropical dry woodlands. Specifically, we characterized different types of deforestation frontier from 2000 to 2020 and compared them to protected areas (PAs), Indigenous Peoples' lands and conservation areas for biodiversity, carbon and water. We found that global conservation priorities were always overrepresented in tropical dry woodlands compared to the rest of the globe (between 4% and 96% more than expected, depending on the type of conservation priority). Moreover, about 41% of all dry woodlands were characterized as deforestation frontiers, and these frontiers have been falling disproportionately in areas with important regional (i.e. tropical dry woodland) conservation assets. While deforestation frontiers were identified within all tropical dry woodland classes of woodland protection, they were lower than the average within protected areas coinciding with Indigenous Peoples' lands (23%), and within other PAs (28%). However, within PAs, deforestation frontiers have also been disproportionately affecting regional conservation assets. Many emerging deforestation frontiers were identified outside but close to PAs, highlighting a growing threat that the conserved areas of dry woodland will become isolated. Understanding how deforestation frontiers coincide with major types of current woodland protection can help target context-specific conservation policies and interventions to tropical dry woodland conservation assets (e.g. PAs in which deforestation is rampant require stronger enforcement, inactive deforestation frontiers could benefit from restoration). Our analyses also identify recurring patterns that can be used to test the transferability of governance approaches and promote learning across social-ecological contexts.


Assuntos
Conservação dos Recursos Naturais , Florestas , Biodiversidade , Carbono
6.
J Fungi (Basel) ; 9(5)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37233219

RESUMO

Elucidating the complex relationship between plants and endophytic fungi is very important in order to understand the maintenance of biodiversity, equity, stability, and ecosystem functioning. However, knowledge about the diversity of endophytic fungi from species of the native Brazilian Cerrado biome is poorly documented and remains largely unknown. These gaps led us to characterize the diversity of Cerrado endophytic foliar fungi associated with six woody species (Caryocar brasiliense, Dalbergia miscolobium, Leptolobium dasycarpum, Qualea parviflora, Ouratea hexasperma, and Styrax ferrugineus). Additionally, we investigated the influence of host plant identities on the structure of fungal communities. Culture-dependent methods coupled with DNA metabarcoding were employed. Irrespective of the approach, the phylum Ascomycota and the classes Dothideomycetes and Sordariomycetes were dominant. Using the cultivation-dependent method, 114 isolates were recovered from all the host species and classified into more than 20 genera and 50 species. Over 50 of the isolates belonged to the genus Diaporthe, and were distributed into more than 20 species. Metabarcoding revealed the phyla Chytridiomycota, Glomeromycota, Monoblepharomycota, Mortierellomycota, Olpidiomycota, Rozellomycota, and Zoopagomycota. These groups are reported for the first time as components of the endophytic mycobiome of Cerrado plant species. In total, 400 genera were found in all host species. A unique leaf endophytic mycobiome was identified in each host species, which differed not only by the distribution of fungal species, but also by the abundance of shared species. These findings highlight the importance of the Brazilian Cerrado as a reservoir of microbial species, and emphasize how endophytic fungal communities are diversified and adapted.

7.
Sci Rep ; 13(1): 4829, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964148

RESUMO

Wildfires are aggravating due to climate change. Public policies need territorial intelligence to prevent and promptly fight fires, especially in vast regions like Brazil. To this end, we have developed a fire-spread prediction system for the Brazilian Cerrado, the biome most affected by wildfires in South America. The system automatically uploads hot pixels and satellite data to calculate maps of fuels loads, vegetation moisture, and probability of burning for simulating fire spread thrice a day for the entire Cerrado at 25 ha and for nine conservation units at 0.04 ha spatial resolution. In both versions, the model attains 65-89% of spatial match. Model results together with ancillary data, e.g., historical burned areas and annual CO2 emissions from fires, are available on an interactive web-platform that serves as a tool for fire prevention and fight, particularly in the selected conservation units where the platform is being used for daily operations.

8.
Glob Chang Biol ; 28(22): 6807-6822, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36073184

RESUMO

The Brazilian Cerrado is one of the most biodiverse savannas in the world, yet 46% of its original cover has been cleared to make way for crops and pastures. These extensive land-use transitions (LUTs) are expected to influence regional climate by reducing evapotranspiration (ET), increasing land surface temperature (LST), and ultimately reducing precipitation. Here, we quantify the impacts of LUTs on ET and LST in the Cerrado by combining MODIS satellite data with annual land use and land cover maps from 2006 to 2019. We performed regression analyses to quantify the effects of six common LUTs on ET and LST across the entire gradient of Cerrado landscapes. Results indicate that clearing forests for cropland or pasture increased average LST by ~3.5°C and reduced mean annual ET by 44% and 39%, respectively. Transitions from woody savannas to cropland or pasture increased average LST by 1.9°C and reduced mean annual ET by 27% and 21%, respectively. Converting native grasslands to cropland or pasture increased average LST by 0.9 and 0.6°C, respectively. Conversely, grassland-to-pasture transitions increased mean annual ET by 15%. To date, land changes have caused a 10% reduction in water recycled to the atmosphere annually and a 0.9°C increase in average LST across the biome, compared to the historic baseline under native vegetation. Global climate changes from increased atmospheric greenhouse gas concentrations will only exacerbate these effects. Considering potential future scenarios, we found that abandoning deforestation control policies or allowing legal deforestation to continue (at least 28.4 Mha) would further reduce yearly ET (by -9% and -3%, respectively) and increase average LST (by +0.7 and +0.3°C, respectively) by 2050. In contrast, policies encouraging zero deforestation and restoration of the 5.2 Mha of illegally deforested areas would partially offset the warming and drying impacts of land-use change.


O Cerrado brasileiro é uma das savanas mais biodiversas do mundo. Apesar disso, 46% da sua cobertura original foi desmatada para dar lugar a cultivos agrícolas e pastos. Estas extensas transições de uso do solo (LUT) têm o potencial de influenciar o clima regional, reduzindo a evapotranspiração (ET), aumentando a temperatura da superfície terrestre (LST) e por fim reduzindo a precipitação. O objetivo deste estudo foi quantificar os impactos de LUTs sobre ET e LST no Cerrado, combinando dados do satélite MODIS com mapas anuais de uso e cobertura do solo de 2006-2019. Foram realizadas análises de regressão para quantificar os efeitos de seis LUTs usuais sobre ET e LST, ao longo de todo o gradiente de paisagens do Cerrado. Os resultados indicaram que a retirada de florestas para dar lugar à agricultura ou pastagem aumentou a LST média em ~3.5°C e reduziu a ET média anual em 44% e 39%, respectivamente. Transições de formações savânicas para agricultura ou pastagem aumentaram a LST média em 1.9°C e reduziram a ET média anual em 27% e 21%, respectivamente. A conversão de campos nativos para agricultura ou pastagem aumentou a LST média em 0.9 e 0.6°C, respectivamente. Em contrapartida, transições de formações campestres nativas para pastagens aumentaram a ET média anual em 15%. Até o momento, as mudanças de uso do solo causaram redução de 10% da água reciclada para a atmosfera anualmente e aumento de 0.9°C da LST média ao longo do bioma, em comparação com a linha de base histórica sob vegetação nativa. As mudanças climáticas globais decorrentes do aumento das concentrações atmosféricas de gases do efeito estufa irão exacerbar esses efeitos. Considerando potenciais cenários futuros, observou-se que o abandono das políticas de controle do desmatamento ou o avanço do desmatamento legal (ao menos 28.4 Mha) reduziriam a ET anual (em −9% e −3%, respectivamente) e aumentariam a LST média (em +0.7 e +0.3ºC, respectivamente) até 2050. Por outro lado, políticas que promovam desmatamento zero e restauração dos 5.2 Mha de áreas ilegalmente desmatadas compensariam parte dos impactos de aquecimento e seca causados por alterações de uso do solo.


Assuntos
Ecossistema , Gases de Efeito Estufa , Agricultura , Conservação dos Recursos Naturais , Florestas , Água
9.
Biota Neotrop. (Online, Ed. ingl.) ; 22(spe): e20221394, 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1394014

RESUMO

Abstract speciesLink is a large-scale biodiversity information portal that exists thanks to a broad collaborative network of people and institutions. CRIA's involvement with the scientific community of Brazil and other countries is responsible for the significant results achieved, currently reaching more than 15 million primary biodiversity data records, 95% of which are associated with preserved specimens and about 25% with high-quality digital images. The network provides data on over 200,000 species, of which over 110,000 occur in Brazil. This article describes thematic networks within speciesLink, as well as some of the most useful tools developed. The importance and contributions of speciesLink are outlined, as are concerns about securing stable budgetary support for such biodiversity data e-infrastructures. Here we review the value of speciesLink as a major source of biodiversity information for research, education, informed decision-making, policy development, and bioeconomy.


Resumo speciesLink é um portal de informações em larga escala sobre biodiversidade, que existe graças a uma ampla rede colaborativa de pessoas e instituições. O envolvimento do CRIA com a comunidade científica do Brasil e de outros países é responsável pelos resultados expressivos alcançados, atingindo atualmente mais de 15 milhões de registros de dados primários de biodiversidade, sendo 95% associados a espécimes preservados e cerca de 25% a imagens digitais de alta qualidade. A rede fornece dados sobre mais de 200.000 espécies, das quais mais de 110.000 ocorrem no Brasil. Este artigo descreve as redes temáticas do speciesLink, bem como algumas das ferramentas mais úteis desenvolvidas. A importância e as contribuições do speciesLink são destacadas, assim como as preocupações em garantir um apoio financeiro estável para e-infraestruturas de dados sobre biodiversidade. Aqui revisamos o valor do speciesLink como uma das principais fontes de informação sobre biodiversidade para pesquisa, educação, tomada de decisão, desenvolvimento de políticas e bioeconomia.

10.
iScience ; 24(4): 102349, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33870141

RESUMO

Biological nitrogen fixation (BNF) represents the main input source of N in tropical savannas. BNF could be particularly important for Brazilian savannas (known as Cerrado) that show a highly conservative N cycle. We evaluated the effects of seasonal precipitation and nutrient additions on the nifH gene abundance in soils from a long-term fertilization experiment in a Cerrado's native area. The experiment consists of five treatments: (1) control, (2) liming, (3) nitrogen (N), (4) nitrogen + phosphorus (NP), and (5) phosphorus (P) additions. The nifH gene sequence was related to Bradyrhizobium members. Seasonal effects on N-fixing potential were observed by a decrease in the nifH relative abundance from rainy to dry season in control, N, and NP treatments. A significant reduction in nifH abundance was found in the liming treatment in both seasons. The findings evidenced the multiple factors controlling the potential N-fixing by free-living diazotrophs in these nutrient-limited and seasonally dry ecosystems.

11.
Microb Ecol ; 81(3): 563-578, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32829441

RESUMO

Natural ponds in the Brazilian Cerrado harbor high biodiversity but are still poorly studied, especially their microbial assemblage. The characterization of the microbial community in aquatic environments is fundamental for understanding its functioning, particularly under the increasing pressure posed by land conversion and climate change. Here, we aim to characterize the structure (abundance, richness, and diversity) and composition of the Bacteria and Archaea in the sediment of two natural ponds belonging to different basins that primarily differ in size and depth in the Cerrado. Sediment samples were collected in the dry and rainy seasons and the transition periods between both. The structure and composition of Bacteria and Archaea were assessed by 16S rRNA gene pyrosequencing. We identified 45 bacterial and four archaeal groups. Proteobacteria and Acidobacteria dominated the bacterial community, while Euryarchaeota and Thaumarchaeota dominated the archaeal community. Seasonal fluctuations in the relative abundance of microbial taxa were observed, but pond characteristics were more determinant to community composition differences. Microbial communities are highly diverse, and local variability could partially explain the microbial structure's main differences. Functional predictions based in 16S rRNA gene accessed with Tax4Fun indicated an enriched abundance of predicted methane metabolism in the deeper pond, where higher abundance of methanogenic archaea Methanocella, Methanosaeta, and Methanomicrobiaceae was detected. Our dataset encompasses the more comprehensive survey of prokaryotic microbes in Cerrado's aquatic environments. Here, we present basic and essential information about composition and diversity, for initial insights into the ecology of Bacteria and Archaea in these environments.


Assuntos
Archaea , Lagoas , Archaea/genética , Bactérias/genética , Biodiversidade , Sedimentos Geológicos , Filogenia , RNA Ribossômico 16S/genética
12.
Microorganisms ; 8(10)2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32992494

RESUMO

Eusocial animals, such as the termites, often build a nest-like structure called a mound that provides shelter with stable internal conditions and protection against predators. Termites are important components of the Brazilian Cerrado biota. This study aimed to investigate the bacterial community composition and diversity of the Syntermes wheeleri termite-mound soil using culture-independent approaches. We considered the vertical profile by comparing two different mound depths (mound surface and 60 cm) and seasonality with samplings during the rainy and dry seasons. We compared the mound soil microbiota to the adjacent soil without the influence of the mound to test the hypothesis that the Cerrado soil bacterial community was more diverse and more susceptible to seasonality than the mound soil microbiota. The results support the hypothesis that the Cerrado soil bacterial community is more diverse than the mound soil and also has a higher variability among seasons. The number of observed OTUs (Operational Taxonomic Units) was used to express bacterial richness, and it indicates that soil moisture has an effect on the community distribution and richness of the Cerrado samples in comparison to mound samples, which remain stable across seasons. This could be a consequence of the protective role of the mound for the termite colony. The overall community taxonomic profile was similar between soil samples, especially when compared to the taxonomic composition of the Syntermes wheeleri termite's gut, which might be explained by the different characteristics and functionality between the soil and the gut microbial community.

13.
Sci Rep ; 10(1): 11365, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647221

RESUMO

Worldwide, alien plant invasions have been intensively studied in the past decades, but mechanisms controlling the invasibility of native communities are not fully understood yet. The stochastic niche hypothesis predicts that species-rich plant communities are less prone to alien plant invasions than species-poor communities, which is supported by some but not all field studies, with some very species-rich communities such as the Brazilian Cerrado becoming heavily invaded. However, species-rich communities potentially contain a greater variety of facilitative interactions in resource exploitation than species-poor communities, from which invasive plants might benefit. This alternative hypothetical mechanism might explain why nutrient-poor, species-rich ecosystems are prone to invasion. Here we show that a high species richness both impedes and promotes invasive plants in the Brazilian Cerrado, using structural equation modelling and data from 38 field sites. We found support for the stochastic niche hypothesis through an observed direct negative influence of species richness on abundance of alien invasive species, but an indirect positive effect of species richness on invasive alien plants through soil phosphatase activity that enhances P availability was also found. These field observations were supported with results from a mesocosm experiment. Root phosphatase activity of plants increased with species richness in the mesocosms, which was associated with greater community P and N uptake. The most prominent alien grass species of the region, Melinis minutiflora, benefited most from the higher N and P availability in the species mixtures. Hence, this study provides a novel explanation of why species-richness may sometimes promote rather than impede invasion, and highlights the need to perform facilitation experiments in multi-species communities.


Assuntos
Espécies Introduzidas/estatística & dados numéricos , Dispersão Vegetal/fisiologia , Poaceae/fisiologia , Brasil , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Solo/química , Microbiologia do Solo , Processos Estocásticos
14.
J Environ Manage ; 232: 818-828, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30529869

RESUMO

The Brazilian Cerrado is the second largest biome in Latin America, extending over more than 200 million ha and hosts some of the most intensive agricultural activities for grain and beef production in the world. Because of the biodiversity richness and high levels of endemism, Cerrado is considered one of world's hotspot for biodiversity conservation. The objectives of this study are three-fold: to present a comprehensive division of Cerrado into different ecoregions that reflect the environmental heterogeneity within the biome; to analyze the ecoregions in terms of biophysical characteristics, protected areas, environmental liability in riparian permanent protection areas along watercourses, and priorities for biodiversity conservation; and to rank the ecoregions in terms of endangerment for biodiversity conservation and restoration. A previous study that delineated 22 ecoregions using geomorphology, vegetation, soil, geology, and plant diversity maps was revised using topography, vegetation, precipitation, and soil maps. Our new ecoregion map consists of 19 units that are unique in terms of landscape characteristics and has been adjusted to the current official boundary map of Cerrado. Some of the ecoregions consist of only one geomorphological compartment, whereas others are heterogeneous, consisting of up to eight compartments. Ferralsols comprise the dominant soil type in 14 of the ecoregions. The percentage of protected areas within ecoregions ranges from 1.7% to 51.5%. The most endangered ecoregion, where land use change critically threatens habitat integrity, is the Depressão Cárstica do São Francisco (states of Bahia, Minas Gerais, and Piauí), where environmental liability along riparian permanent protection areas amounts to 85.6% of the total area. Our proposed ecoregion map provides a spatial framework for regional and local assessments to improve decision-making processes to reconcile conservation and restoration planning, sustainable agriculture, and provision of ecosystem services. Besides de adjustment of the previous Cerrado's ecoregion map to the official biome boundary (relevant for the implementation of public policies of conservation as those regulated by the Brazilian Forest Code), the new analyses of the ecoregion map represent a substantial improvement in comparison to the ones conducted by the previous study in 2003. In addition, current web resources allow us to make all the information used or derived from this study available to other users. This opens the possibility of additional improvements of our findings by the scientific community or to be used effectively by decision makers.


Assuntos
Ecossistema , Pradaria , Agricultura , Biodiversidade , Brasil , Conservação dos Recursos Naturais
15.
Biota Neotrop. (Online, Ed. ingl.) ; 19(4): e20190865, 2019. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1038864

RESUMO

Abstract: Biodiversity and ecosystems are important elements for addressing national and global socioeconomic and environmental crises, since they provide new development opportunities, for example, as source of job and income creation, and reduction in poverty and socioeconomic inequity. Brazilian biological diversity is also expressed in its immense cultural diversity, with a great variety of knowledge holders. These peoples possess vast knowledge on agrobiodiversity, fishing, fire management, natural medicine, among others of commercial, cultural and spiritual value. The main conclusions of this Summary for Police Makers is that land use changes and climate changes have been - and will continue to be throughout this century - the main drivers that result in the loss of biodiversity and ecosystem services in the country. Political interventions at different levels (from local to national, from public to private) and the enforcement of existing laws (regulatory mechanisms and incentives) are required to cope with the mitigation of the negative impacts of biodiversity and ecosystem services loss. Brazil has already a wide variety of policy instruments and socioenvironmental governance options, as well as global commitments (ODS, Aich Targets, Paris Agreement) related to the objective of a sustainable future. However, inefficient management control or lack of incentive to comply with the rules pose risks to consolidating the path to this future. The country has strong and capable institutions, but infrastructural problems, slow processes, inefficient measurements and judicial, social and ecological conflicts obstruct a proficient performance. There is a lack of communication between science and society which needs to be improved by establishing an effective flow that makes communication inclusive and representative, reaching public and private decision makers. Permanent efforts to integrate Science and policy knowledges are desirable to build confidence between policy makers and researchers.


Resumo: A biodiversidade e os ecossistemas são elementos importantes para enfrentar as crises socioeconômicas e ambientais nacionais e globais, uma vez que proporcionam novas oportunidades de desenvolvimento. Incorporar a biodiversidade na vida cotidiana é uma oportunidade de ouro para promover o uso sustentável da biodiversidade e dos serviços ecossistêmicos. A conservação e a restauração da biodiversidade, dos ecossistemas e de seus serviços associados mostram potencial para um novo desenvolvimento social e econômico, como fonte de geração de emprego e renda, redução da pobreza e da desigualdade socioeconômica. A diversidade biológica brasileira também se expressa em sua imensa diversidade cultural, com uma grande variedade de detentores de conhecimento indígenas e tradicionais. Esses povos possuem vasto conhecimento sobre agrobiodiversidade, pesca, manejo do fogo, medicina natural, entre outros de valor comercial, cultural e espiritual. As principais conclusões deste Sumário para Tomadores de Decisão é que as mudanças no uso da terra e as mudanças climáticas tenham sido - e continuarão sendo ao longo deste século - os principais vetores da perda de biodiversidade e serviços ecossistêmicos no país. Intervenções políticas em diferentes níveis (do local ao nacional, do público ao privado) e a aplicação das leis existentes (mecanismos regulatórios e incentivos) são necessárias para promover a mitigação dos impactos negativos sobre a biodiversidade e a perda de serviços ecossistêmicos. O Brasil já possui uma ampla variedade de instrumentos de política e opções de governança socioambiental, bem como compromissos globais (ODS, Metas de Aichi, Acordo de Paris) relacionados à possibilidade de um futuro sustentável. Entretanto, o controle ineficiente da gestão ou a falta de incentivo para cumprir as regras traz riscos para a consolidação do caminho para esse futuro. O país tem instituições fortes e capazes, mas problemas de infraestrutura, processos lentos, medidas ineficazes e conflitos judiciais, sociais e ecológicos impedem a realização de um desempenho eficiente. Há uma falta de comunicação entre a ciência e a sociedade que precisa ser melhorada por meio do estabelecimento de um fluxo efetivo que torne a comunicação inclusiva e representativa, alcançando os tomadores de decisão públicos e privados. Esforços permanentes para integrar essas duas esferas de conhecimento na sociedade são desejáveis para criar confiança entre os formuladores de políticas e os pesquisadores.

16.
PLoS One ; 13(11): e0204460, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30388124

RESUMO

The demand for insect-pollinated crops is increasing. Conventional agricultural intensification heavily relies on increased input of fertilizers, which can have negative effects on local biodiversity. Such effects may be particularly accentuated in biodiversity hotspots that are naturally nutrient-poor. Ecological intensification of farming, i.e. practices that increase production through the increase of ecosystem services, emerges as an alternative to conventional intensification. For example, practices that boost abundance and diversity of crop pollinators can lead to substantial increases in cropland productivity. However, little is known about the synergisms and trade-offs between fertilizer input and such ecological intensification practices. Here we investigate interactive effects between fertilization practices and the provision of ecosystem services in a biodiversity hotspot where conventional agriculture is rapidly expanding (Brazilian savannas). We focus on a highly nitrogen-demanding crop species that benefits from pollinators (the common bean, Phaseolus vulgaris L.), for which nitrogen input greatly varies in the study region. Our findings show that positive effects of native pollinators on crop yield are most accentuated under low inputs of nitrogen (e.g. equal to or below 72kg ha-1). This interactive effect could be due to changes in flower visitor community composition or behaviour. Our study also suggests that landscape management practices that minimize isolation from patches of natural vegetation and maximize its cover nearby (within 500 meters) of production areas can increase pollinator and biocontrol agent abundance and richness. Overall, these results suggest that ecological intensification is a valuable alternative for common bean production in Brazil, and potentially other regions of the world. Land productivity can be enhanced if an adequate balance of chemical inputs and landscape management is achieved.


Assuntos
Agricultura , Produtos Agrícolas/fisiologia , Fertilizantes , Phaseolus/fisiologia , Polinização , Agricultura/métodos , Animais , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Fertilizantes/análise , Insetos/fisiologia , Nitrogênio/análise
17.
PLoS One ; 13(8): e0196742, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30067735

RESUMO

Cerrado is the second largest biome in South America and accounted for the second largest contribution to carbon emissions in Brazil for the last 10 years, mainly due to land-use changes. It comprises approximately 2 million km2 and is divided into 22 ecoregions, based on environmental conditions and vegetation. The most dominant vegetation type is cerrado sensu stricto (cerrado ss), a savanna woodland. Quantifying variation of biomass density of this vegetation is crucial for climate change mitigation policies. Integrating remote sensing data with adequate allometric equations and field-based data sets can provide large-scale estimates of biomass. We developed individual-tree aboveground biomass (AGB) allometric models to compare different regression techniques and explanatory variables. We applied the model with the strongest fit to a comprehensive ground-based data set (77 sites, 893 plots, and 95,484 trees) to describe AGB density variation of cerrado ss. We also investigated the influence of physiographic and climatological variables on AGB density; this analysis was restricted to 68 sites because eight sites could not be classified into a specific ecoregion, and one site had no soil texture data. In addition, we developed two models to estimate plot AGB density based on plot basal area. Our data show that for individual-tree AGB models a) log-log linear models provided better estimates than nonlinear power models; b) including species as a random effect improved model fit; c) diameter at 30 cm above ground was a reliable predictor for individual-tree AGB, and although height significantly improved model fit, species wood density did not. Mean tree AGB density in cerrado ss was 22.9 tons ha-1 (95% confidence interval = ± 2.2) and varied widely between ecoregions (8.8 to 42.2 tons ha-1), within ecoregions (e.g. 4.8 to 39.5 tons ha-1), and even within sites (24.3 to 69.9 tons ha-1). Biomass density tended to be higher in sites close to the Amazon. Ecoregion explained 42% of biomass variation between the 68 sites (P < 0.01) and shows strong potential as a parameter for classifying regional biomass variation in the Cerrado.


Assuntos
Biomassa , Ecossistema , Modelos Teóricos , Brasil , Mudança Climática , Meio Ambiente , Florestas , Clima Tropical
18.
PLoS One ; 11(2): e0148785, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26849674

RESUMO

The Cerrado, the largest savanna region in South America, is located in central Brazil. Cerrado physiognomies, which range from savanna grasslands to forest formations, combined with the highly weathered, acidic clay Cerrado soils form a unique ecoregion. In this study, high-throughput sequencing of ribosomal RNA genes was combined with shotgun metagenomic analysis to explore the taxonomic composition and potential functions of soil microbial communities in four different vegetation physiognomies during both dry and rainy seasons. Our results showed that changes in bacterial, archaeal, and fungal community structures in cerrado denso, cerrado sensu stricto, campo sujo, and gallery forest soils strongly correlated with seasonal patterns of soil water uptake. The relative abundance of AD3, WPS-2, Planctomycetes, Thermoprotei, and Glomeromycota typically decreased in the rainy season, whereas the relative abundance of Proteobacteria and Ascomycota increased. In addition, analysis of shotgun metagenomic data revealed a significant increase in the relative abundance of genes associated with iron acquisition and metabolism, dormancy, and sporulation during the dry season, and an increase in the relative abundance of genes related to respiration and DNA and protein metabolism during the rainy season. These gene functional categories are associated with adaptation to water stress. Our results further the understanding of how tropical savanna soil microbial communities may be influenced by vegetation covering and temporal variations in soil moisture.


Assuntos
Archaea , Bactérias , Fungos , Pradaria , Metagenoma , Microbiologia do Solo , Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Brasil , Fungos/classificação , Fungos/genética , Fungos/crescimento & desenvolvimento
19.
Glob Chang Biol ; 22(3): 1008-28, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26301476

RESUMO

Soils are subject to varying degrees of direct or indirect human disturbance, constituting a major global change driver. Factoring out natural from direct and indirect human influence is not always straightforward, but some human activities have clear impacts. These include land-use change, land management and land degradation (erosion, compaction, sealing and salinization). The intensity of land use also exerts a great impact on soils, and soils are also subject to indirect impacts arising from human activity, such as acid deposition (sulphur and nitrogen) and heavy metal pollution. In this critical review, we report the state-of-the-art understanding of these global change pressures on soils, identify knowledge gaps and research challenges and highlight actions and policies to minimize adverse environmental impacts arising from these global change drivers. Soils are central to considerations of what constitutes sustainable intensification. Therefore, ensuring that vulnerable and high environmental value soils are considered when protecting important habitats and ecosystems, will help to reduce the pressure on land from global change drivers. To ensure that soils are protected as part of wider environmental efforts, a global soil resilience programme should be considered, to monitor, recover or sustain soil fertility and function, and to enhance the ecosystem services provided by soils. Soils cannot, and should not, be considered in isolation of the ecosystems that they underpin and vice versa. The role of soils in supporting ecosystems and natural capital needs greater recognition. The lasting legacy of the International Year of Soils in 2015 should be to put soils at the centre of policy supporting environmental protection and sustainable development.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Poluição Ambiental/efeitos adversos , Solo
20.
Glob Chang Biol ; 22(1): 92-109, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26390852

RESUMO

Tropical forests harbor a significant portion of global biodiversity and are a critical component of the climate system. Reducing deforestation and forest degradation contributes to global climate-change mitigation efforts, yet emissions and removals from forest dynamics are still poorly quantified. We reviewed the main challenges to estimate changes in carbon stocks and biodiversity due to degradation and recovery of tropical forests, focusing on three main areas: (1) the combination of field surveys and remote sensing; (2) evaluation of biodiversity and carbon values under a unified strategy; and (3) research efforts needed to understand and quantify forest degradation and recovery. The improvement of models and estimates of changes of forest carbon can foster process-oriented monitoring of forest dynamics, including different variables and using spatially explicit algorithms that account for regional and local differences, such as variation in climate, soil, nutrient content, topography, biodiversity, disturbance history, recovery pathways, and socioeconomic factors. Generating the data for these models requires affordable large-scale remote-sensing tools associated with a robust network of field plots that can generate spatially explicit information on a range of variables through time. By combining ecosystem models, multiscale remote sensing, and networks of field plots, we will be able to evaluate forest degradation and recovery and their interactions with biodiversity and carbon cycling. Improving monitoring strategies will allow a better understanding of the role of forest dynamics in climate-change mitigation, adaptation, and carbon cycle feedbacks, thereby reducing uncertainties in models of the key processes in the carbon cycle, including their impacts on biodiversity, which are fundamental to support forest governance policies, such as Reducing Emissions from Deforestation and Forest Degradation.


Assuntos
Biodiversidade , Ciclo do Carbono , Carbono , Florestas , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Agricultura Florestal/métodos , Modelos Teóricos , Clima Tropical
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