Influência de gradientes ambientais nos padrões de diversidade das comunidades campestres nos Campos de Cima da Serra, RS, Brasil

Os Campos de Cima da Serra são uma das principais tipologias dos Campos Sulinos e seus remanescentes ocupavam, em 2002, uma área de 7.653 km2. Eles coexistem com manchas de floresta com Araucária, sendo que o clima atual gera uma tensão permanente ao favorecer o adensamento com arbustos e o avanço da colonização florestal. Por outro lado, estão sujeitos a um intenso regime de distúrbios (pastejo e queimadas periódicas), que detém a colonização de espécies lenhosas e afeta profundamente a estrutura das comunidades campestres. As consequências destes processos sobre a diversidade dessas comunidades campestres ainda não são totalmente compreendidas. Os principais objetivos do estudo incluíram: a descrição da diversidade florística e da composição funcional, a identificação de tipos de comunidades e de suas espécies indicadoras. Também foi avaliada a influência relativa de um conjunto de variáveis ambientais (clima, solos, geomorfologia da paisagem e topografia local) e de fatores espaciais para modelar a riqueza de espécies e a diversidade β. Além disso, buscou-se identificar as escalas espaciais com as maiores variações na diversidade β. Um estudo regional foi conduzido com amostragem de 320 parcelas em um delineamento aleatório estratificado e aninhado, de forma a incluir gradientes ambientais numa amplitude geográfica de 160 km de latitude e 170 km de longitude. Foi utilizada Análise de Redundância (RDA) e Análise de Redundância parcial (pRDA) para decompor as influências relativas dos fatores ambientais e espaciais sobre a diversidade β e sobre a riqueza de espécies. Os fatores espaciais foram avaliados com base na Análise de Coordenadas Principais de Matrizes Vizinhas (PCNM). Para decompor a diversidade γ nos componentes α e β foi utilizada a partição aditiva da diversidade considerando cinco escalas espaciais: parcelas (320), transecções (64), sítios (16), sub-regiões (8) e regiões (4), seguida de aleatorizações baseadas em modelos nulos para testar se os valores observados foram casuais. A magnitude e a extensão da correlação espacial na composição das espécies foram avaliadas com o correlograma de Mantel. Um total de 390 táxons pertencentes a 53 famílias foi registrado. Quatro tipos de comunidades foram identificados e a alta riqueza de espécie na escala das parcelas, além da alta riqueza de herbáceas não graminóides foram características indicadoras do regime geral de distúrbios. Um total de 41,4 % da variação na composição das comunidades foi explicado pelas variáveis ambientais e espaciais utilizadas. O efeito dos gradientes ambientais representou cerca de um terço da variação total, sendo na maior parte espacialmente estruturado. A fração espacial pura representou apenas 5,7 % da variação total. A fração das variáveis ambientais sem estrutura espacial foi também baixa. As variáveis representando gradientes de clima e tipos de solo sobrepujaram o efeito da topografia local. A temperatura anual média, a sazonalidade da temperatura e o tipo de solo foram as principais variáveis selecionadas para modelar a diversidade β. A partição aditiva da diversidade revelou que a maior proporção da diversidade β ocorreu em escalas mais amplas, com 46,3% da diversidade total representada pela escala de regiões. A alta proporção de espécies pouco frequentes sugere que áreas protegidas de grandes dimensões são necessárias para representar a maioria das espécies, entretanto os resultados de diversidade β demonstraram que sua efetividade para conservar a diversidade seria incrementada se a área a ser conservada fosse dividida entre as quatro regiões amostradas. Um artigo final de opinião complementou o trabalho com o argumento de que os distúrbios são essenciais para conservar a diversidade dos campos e devem ser reintroduzidos nas áreas protegidas que protegem os campos com ações específicas de manejo.The Campos de Cima da Serra are one of the main physiognomies of the South Brazilian Campos with a remnant area of 7.653 km2 recorded in 2002. They coexist with patches of Araucaria forest, but current climate conditions favors encroachment and forest colonization over grasslands. On the other hand, there is a widespread regime of disturbances (grazing and periodic burns) that prevents the colonization by woody plants and deeply affect the structure of grassland communities. The consequences of both processes on the diversity of these grasslands are still not fully understood. Our main objectives included describing their floristic and functional diversity and identifying community types and associated indicator species. We evaluated the relative role of a set of environmental variables (climate, soil, landscape geomorphology and local topography) and of spatial factors to model the grasslands species richness and β diversity. We also searched for the spatial scales with the larger variations in β diversity. A regional survey was designed to sample 320 plots in a random stratified and nested sampling to encompass environmental gradients within an area ranging 160 km of latitude and 170 km of longitude. We used Redundancy Analysis (RDA) and Partial RDA to disentangle the relative role of the environmental and spatial drivers and to model β diversity and species richness. The spatial factors were evaluated using PCNM eigenfunctions. To decompose γ diversity into α and β components we used additive partitioning considering five spatial scales: plots (320), transects (64), sites (16), sub-regions (8) and regions (4) followed by randomization procedures with null models to test if observed values were random. The magnitude and extension of the spatial correlation among species composition were evaluated with a Mantel correlogram. A total of 390 taxa belonging to 53 families was recorded. Four community types were revealed and the high species richness at the plot level and the high forbs richness were indicative of the general disturbance regime. A total of 41.4% of the variation of community composition was explained jointly by the environmental and spatial variables. The environmental effect accounted for nearly one third of total variation, mostly spatially structured. The pure space fraction accounted for only 5.7% of total variation. The fraction of environmental variables not spatially structured was also low. Variables representing regional gradients of climate and soil overwhelmed the effect of local topography. Annual mean temperature, temperature seasonality and soil type were the main selected variables to model β diversity. Species richness showed a different pattern with a lower effect of two variables related to water supply and retention suggesting that different forces drive α and β diversity. The observed patterns indicate that niche processes have a considerable influence on β diversity. Diversity additive partitioning revealed a large proportion of β diversity at broader scales, with 46.3 % of overall diversity at the regions scale. The high proportion of less frequent species suggests that a large protected area would be necessary to represent most species. However, β diversity results showed that their effectiveness to conserve grasslands diversity would be improved by splitting the effort to represent each one of the four sampled geographical regions. A final opinion article complement the work arguing that disturbances are essential to conserve grasslands diversity and shall be reintroduced within grasslands protected areas through specific management actions

The Program for Biodiversity Research in Brazil: The role of regional networks for biodiversity knowledge, dissemination, and conservation

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes

Long-term Landsat-based monthly burned area dataset for the Brazilian biomes using Deep Learning

Fire is a significant agent of landscape transformation on Earth, and a dynamic and ephemeral process that is challenging to map. Difficulties include the seasonality of native vegetation in areas affected by fire, the high levels of spectral heterogeneity due to the spatial and temporal variability of the burned areas, distinct persistence of the fire signal, increase in cloud and smoke cover surrounding burned areas, and difficulty in detecting understory fire signals. To produce a large-scale time-series of burned area, a robust number of observations and a more efficient sampling strategy is needed. In order to overcome these challenges, we used a novel strategy based on a machine-learning algorithm to map monthly burned areas from 1985 to 2020 using Landsat-based annual quality mosaics retrieved from minimum NBR values. The annual mosaics integrated year-round observations of burned and unburned spectral data (i.e., RED, NIR, SWIR-1, and SWIR-2), and used them to train a Deep Neural Network model, which resulted in annual maps of areas burned by land use type for all six Brazilian biomes. The annual dataset was used to retrieve the frequency of the burned area, while the date on which the minimum NBR was captured in a year, was used to reconstruct 36 years of monthly burned area. Results of this effort indicated that 19.6% (1.6 million km2) of the Brazilian territory was burned from 1985 to 2020, with 61% of this area burned at least once. Most of the burning (83%) occurred between July and October. The Amazon and Cerrado, together, accounted for 85% of the area burned at least once in Brazil. Native vegetation was the land cover most affected by fire, representing 65% of the burned area, while the remaining 35% burned in areas dominated by anthropogenic land uses, mainly pasture. This novel dataset is crucial for understanding the spatial and long-term temporal dynamics of fire regimes that are fundamental for designing appropriate public policies for reducing and controlling fires in Brazil

sPlotOpen – An environmentally balanced, open-access, global dataset of vegetation plots

Assessing biodiversity status and trends in plant communities is critical for understanding, quantifying and predicting the effects of global change on ecosystems. Vegetation plots record the occurrence or abundance of all plant species co-occurring within delimited local areas. This allows species absences to be inferred, information seldom provided by existing global plant datasets. Although many vegetation plots have been recorded, most are not available to the global research community. A recent initiative, called ?sPlot?, compiled the first global vegetation plot database, and continues to grow and curate it. The sPlot database, however, is extremely unbalanced spatially and environmentally, and is not open-access. Here, we address both these issues by (a) resampling the vegetation plots using several environmental variables as sampling strata and (b) securing permission from data holders of 105 local-to-regional datasets to openly release data. We thus present sPlotOpen, the largest open-access dataset of vegetation plots ever released. sPlotOpen can be used to explore global diversity at the plant community level, as ground truth data in remote sensing applications, or as a baseline for biodiversity monitoring. Main types of variable contained: Vegetation plots (n = 95,104) recording cover or abundance of naturally co-occurring vascular plant species within delimited areas. sPlotOpen contains three partially overlapping resampled datasets (c. 50,000 plots each), to be used as replicates in global analyses. Besides geographical location, date, plot size, biome, elevation, slope, aspect, vegetation type, naturalness, coverage of various vegetation layers, and source dataset, plot-level data also include community-weighted means and variances of 18 plant functional traits from the TRY Plant Trait Database. Spatial location and grain: Global, 0.01?40,000 m². Time period and grain: 1888-2015, recording dates. Major taxa and level of measurement: 42,677 vascular plant taxa, plot-level records.Fil: Sabatini, Francesco Maria. Martin-universität Halle-wittenberg; Alemania. German Centre For Integrative Biodiversity Research (idiv) Halle-jena-leipzig; AlemaniaFil: Lenoir, Jonathan. Université de Picardie Jules Verne; FranciaFil: Hattab, Tarek. Université de Montpellier; FranciaFil: Arnst, Elise Aimee. Manaaki Whenua - Landcare Research; Nueva ZelandaFil: Chytrý, Milan. Masaryk University; República ChecaFil: Giorgis, Melisa Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Vanselow, Kim André. University of Erlangen-Nuremberg; AlemaniaFil: Vásquez Martínez, Rodolfo. Jardín Botánico de Missouri Oxapampa; PerúFil: Vassilev, Kiril. Bulgarian Academy of Sciences; BulgariaFil: Vélez-Martin, Eduardo. ILEX Consultoria Científica; BrasilFil: Venanzoni, Roberto. University of Perugia; ItaliaFil: Vibrans, Alexander Christian. Universidade Regional de Blumenau; BrasilFil: Violle, Cyrille. Paul Valéry Montpellier University; FranciaFil: Virtanen, Risto. German Centre for Integrative Biodiversity Research; AlemaniaFil: von Wehrden, Henrik. Leuphana University of Lüneburg; AlemaniaFil: Wagner, Viktoria. University of Alberta; CanadáFil: Walker, Donald A.. University of Alaska; Estados UnidosFil: Waller, Donald M.. University of Wisconsin-Madison; Estados UnidosFil: Wang, Hua-Feng. Hainan University; ChinaFil: Wesche, Karsten. Senckenberg Museum of Natural History Görlitz; Alemania. Technische Universität Dresden; AlemaniaFil: Whitfeld, Timothy J. S.. University of Minnesota; Estados UnidosFil: Willner, Wolfgang. University of Vienna; AustriaFil: Wiser, Susan K.. Manaaki Whenua. Landcare Research; Nueva ZelandaFil: Wohlgemuth, Thomas. Swiss Federal Institute for Forest, Snow and Landscape Research; SuizaFil: Yamalov, Sergey. Russian Academy of Sciences; RusiaFil: Zobel, Martin. University of Tartu; EstoniaFil: Bruelheide, Helge. German Centre for Integrative Biodiversity Research; Alemani

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Data from: Local biodiversity erosion in South Brazilian grasslands under moderate levels of landscape habitat loss

1.Habitat loss is one of the greatest threats to biodiversity, exerting negative effects on the ecological viability of natural vegetation remnants. The South Brazilian grasslands belong to one of the largest temperate grassland regions in the world, but have lost 50% of their natural extent in the past 35 years. To date, there is no empirical evidence for the effects of habitat loss on these grasslands’ biological diversity, undermining their conservation. 2.Using data from a large-scale biodiversity survey, we asked if local plant communities respond to levels of habitat loss representative of the entire region (≤50%). Vegetation in grassland remnants was sampled in 24 landscapes at three localities each, using 9 plots per locality. To investigate whether species losses were a consequence of stochastic or nonrandom local extinctions and whether plant communities became more homogenized, we evaluated species richness, beta-diversity components (spatial turnover and nestedness), and phylogenetic diversity, in respect to landscape change. In part of the landscapes, arthropods were sampled to investigate if loss of plant diversity had a cascading effect on other trophic levels. We evaluated generic richness of ants, an omnivore group with high levels of plant associations, in respect to a plant community's phylogenetic diversity. 3.Local plant communities in landscapes with less grassland cover had fewer species, less spatial turnover, increased nestedness and lower phylogenetic diversity. Our results suggest that the observed species loss can be linked to taxonomic homogenization and is nonrandom, decreasing evolutionary diversity within the community. Furthermore, ant richness declined by 50% in plant communities with the lowest phylogenetic diversity, suggesting that effects of habitat loss propagate to higher trophic levels. 4.Policy implications. We conclude that the biological diversity of South Brazilian grasslands, at the producer and consumer level, is at risk under the current rate of land use conversion, even at habitat losses below 50%. To avoid substantial biodiversity loss, conservation and more restrictive policies for conversion of native grasslands to different land uses in South Brazil are urgent

Data from: Local biodiversity erosion in South Brazilian grasslands under moderate levels of landscape habitat loss

1.Habitat loss is one of the greatest threats to biodiversity, exerting negative effects on the ecological viability of natural vegetation remnants. The South Brazilian grasslands belong to one of the largest temperate grassland regions in the world, but have lost 50% of their natural extent in the past 35 years. To date, there is no empirical evidence for the effects of habitat loss on these grasslands’ biological diversity, undermining their conservation. 2.Using data from a large-scale biodiversity survey, we asked if local plant communities respond to levels of habitat loss representative of the entire region (≤50%). Vegetation in grassland remnants was sampled in 24 landscapes at three localities each, using 9 plots per locality. To investigate whether species losses were a consequence of stochastic or nonrandom local extinctions and whether plant communities became more homogenized, we evaluated species richness, beta-diversity components (spatial turnover and nestedness), and phylogenetic diversity, in respect to landscape change. In part of the landscapes, arthropods were sampled to investigate if loss of plant diversity had a cascading effect on other trophic levels. We evaluated generic richness of ants, an omnivore group with high levels of plant associations, in respect to a plant community's phylogenetic diversity. 3.Local plant communities in landscapes with less grassland cover had fewer species, less spatial turnover, increased nestedness and lower phylogenetic diversity. Our results suggest that the observed species loss can be linked to taxonomic homogenization and is nonrandom, decreasing evolutionary diversity within the community. Furthermore, ant richness declined by 50% in plant communities with the lowest phylogenetic diversity, suggesting that effects of habitat loss propagate to higher trophic levels. 4.Policy implications. We conclude that the biological diversity of South Brazilian grasslands, at the producer and consumer level, is at risk under the current rate of land use conversion, even at habitat losses below 50%. To avoid substantial biodiversity loss, conservation and more restrictive policies for conversion of native grasslands to different land uses in South Brazil are urgent

Reference values and drivers of diversity for South Brazilian grassland plant communities

The South Brazilian grasslands (Campos Sulinos) form the dominant vegetation in southern Brazil. They are species-rich ecosystems that occur under distinct geomorphological and climatic conditions but spatial variation of plant species diversity remains understudied. Here, we present a detailed description of plant communities across the region. Our data were obtained in 1080 plots, representing well-preserved grasslands in different ecological systems. Apart from describing alpha and beta diversity, we investigated the relations of plant communities with environmental features. We identified 759 plant species and found clear differences in community composition across the region. Northern and Southern highland grasslands, humid and dry coastal grasslands and the mesic Pampa grassland were clearly distinct, related to climatic and edaphic features. While species abundance distribution was markedly uneven, local species richness was high, above 20 species/m2, especially in the highlands and in mesic Pampa sites, on shallow soils. The predominant component of beta diversity was species turnover, which suggests that a network of well-conserved grasslands distributed across the region would be the best strategy to protect plant diversity. Our results establish regionalized reference values for richness and diversity that can be useful for initiatives of restoration and conservation of these grasslands

Plant and ant communities along a habitat loss gradient

The file consists of three sheets: "Plants", "Ants" and "Gradient". Plants and Ants are sites x species matrices. Sites are structured as following: "Landscape" is the landscape sampling region (2 x 2 km), in which 3 local sampling units (70 x 70 m), "Unit", are allocated. For Plants each "Unit" is sampled with 9 plots, "Plot". Gradient contains the percentage of grassland remnants, "percent_remGrassland", and the "Latitude" and "Longituted" of each "Landscape"