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Human influence on the environment is so extensive that virtually all ecosystems on the planet are now affected by biological invasions. And, often, ecosystems are invaded by multiple co‐occurring non‐native species. Hence, it is important to understand the impacts these invasions are producing on biodiversity and ecosystem processes. Here, we present results of a 2‐year long field experiment where we tested the effects of co‐occurring invasive C4 African grasses in a Cerrado area in central Brazil. We compared plant and arthropod communities, plant biomass, and soil nitrogen dynamics and soil chemical characteristics across five experimental treatments: Urochloa decumbens removal; Melinis minutiflora removal; both U. decumbens and M. minutiflora removal; U. decumbens and M. minutiflora invaded plots; and uninvaded Cerrado. We hypothesized that selective removal of invasive grasses would have distinct effects on the native ecosystem structure and functioning. We expected that each invasive grass would produce a different type of impact on the native ecosystem and that their impacts would be synergistic when co‐occurring. Removal of M. minutiflora doubled native plant diversity and biomass when compared to invaded plots, whereas removal of U. decumbens did not alter these parameters. Cerrado plots had four times more plant species than plots cleared of invasives. Removal of invasive grasses did not affect the species richness or community composition of soil epigeal fauna. Cerrado soils had lower fertility, organic matter content and pH than invaded soils. The effects were generally higher when both invasive grasses were removed, suggesting impacts were synergistic, but M. minutiflora had greater effects on plants and soils than U. decumbens. Both invasive species produced negative impacts, but a single species was the main driver. We also detected persistent effects of the invasive grass species on the ecosystem after 2 years of removal. We conclude that invasive species of the same functional group have similar types of effects in native ecosystems, but the magnitude of impact was largely dependent on invasive species biomass and cover. Where multiple invasive species are present, research and management of invaded ecosystems should tackle the interacting effects of co‐occurring invaders. Abstrata A influência humana no meio ambiente é tão extensa que praticamente todos os ecossistemas do planeta são afetados por invasões biológicas. E, frequentemente, os ecossistemas são invadidos por várias espécies não‐nativas que ocorrem simultaneamente. Portanto, é importante entender os impactos dessas invasões na biodiversidade e nos processos ecossistêmicos. Neste trabalho nós apresentamos os resultados de um experimento de campo de dois anos onde testamos os efeitos de gramíneas C4 africanas invasoras coocorrentes em uma área de Cerrado no Brasil central. Comparamos as comunidades de plantas e artrópodes, a biomassa das plantas, a dinâmica do nitrogênio e as características químicas do solo em cinco tratamentos experimentais: remoção de Urochloa decumbens, remoção de Melinis minutiflora, remoção de U.  decumbens e M.  minutiflora, nenhuma remoção e Cerrado não invadido. Nossa hipótese foi que a remoção seletiva de gramíneas invasoras teria efeitos distintos sobre a estrutura e o funcionamento do ecossistema nativo. Esperávamos que cada gramínea invasora produzisse um tipo diferente de impacto no ecossistema nativo e que, quando coocorressem, seu impacto seria sinérgico. A remoção de M.  minutiflora dobrou a diversidade de plantas nativas e a biomassa em comparação com as parcelas invadidas, enquanto a remoção de U.  decumbens não alterou esses parâmetros. As parcelas de Cerrado tinham quatro vezes mais espécies de plantas do que as sem plantas invasoras. Em relação à fauna epígea do solo, a remoção de gramíneas invasoras não afetou a riqueza de espécies e a composição da comunidade. Os solos do Cerrado apresentaram menor fertilidade, conteúdo de matéria orgânica e pH do que os solos invadidos. Os efeitos foram geralmente mais altos quando ambas as gramíneas invasoras foram removidas, sugerindo que os impactos eram sinérgicos, mas M.  minutiflora teve maiores efeitos sobre plantas e solos do que U.  decumbens. Ambas as espécies exóticas invasoras produziram impactos negativos, mas uma única espécie foi o principal fator. Também detectamos efeitos persistentes das espécies invasoras de gramíneas no ecossistema após dois anos de remoção. Concluímos que espécies exóticas invasoras do mesmo grupo funcional têm tipos semelhantes de efeitos em ecossistemas nativos, mas a magnitude do impacto foi amplamente dependente da biomassa e da cobertura das espécies invasoras. Considerando os efeitos sinérgicos das espécies invasoras nos ecossistemas, a pesquisa e o manejo de ecossistemas invadidos devem contemplar os efeitos da interação de espécies exóticas invasoras coocorrentes. A free Plain Language Summary can be found within the Supporting Information of this article. A free Plain Language Summary can be found within the Supporting Information of this article.

This note reports the first country records of Tropidurus madeiramamore Carvalho, Paredero, Villalobos-Chaves, Ferreira, Rodrigues & Curcio, 2024 for Bolivia, all northern Beni Department, extending the range by some 300 km to the west of earlier records, clarifying the status of specimens previously reported in the literature as Tropidurus oreadicus Rodrigues, 1987, and providing comments on the biogeographic and conservation values of the Amazonian savannas of the Beni.

1. The Cerrado Domain of central Brazil houses the largest extent of savanna in the Neotropics, but despite its simple characterization as a giant savanna, it contains considerable vegetation heterogeneity that is poorly understood. 2. We aimed to determine how vegetation types in the Cerrado diverge in their tree species composition and what role ecological factors play in driving compositional patterns. 3. We used a dataset of 1,165 tree species inventories spread across the Cerrado Domain, which come from six vegetation types that have a substantial arboreal component: woody savannas, dystrophic cerradāo, mesotrophic cerradāo, seasonally dry tropical forests, semideciduous forests and evergreen forests. We found three extremes in terms of tree species composition, with clear underlying ecological drivers, which leads us to propose a ternary model, the Cerrado Vegetation Triangle, to characterize woody vegetation in the Cerrado. At one extreme, we found that semideciduous and evergreen forests are indistinguishable floristically and are found in areas with high water availability. At another extreme lie seasonally dry tropical forests which are found on more fertile soils. At the third extreme, we found that all types of savanna, and dystrophic cerradão, are highly similar in tree species composition and are commonly found in areas of poor soils and high flammability. Mesotrophic cerradão is transitional in tree species composition between savannas and seasonally dry tropical forest. 4. The lack of variation in tree species composition attributed to climatic variables indicates that within homogeneous macroclimatic zones, many types of forest and savanna co-exist due to complex mosaics of local substrate heterogeneity and fire history. 5. Synthesis. Our findings highlight the complexity of forest-savanna transitions in the Cerrado Domain, with relevance for understanding the future of Cerrado vegetation under environmental change. If nitrogen deposition is extensive, some savannas may be more likely to transition to mesotrophic cerradão or even seasonally dry tropical forest, whereas if water availability increases these same savannas may transition to semideciduous or evergreen forest. Our \"Cerrado Vegetation Triangle\" model offers a simple conceptual tool to frame discussions of conservation and management.

Urea splitting and the use of stabilized ureas in corn (Zea mays L.) crops are management strategies that increase urea efficiency and reduce nitrogen (N) losses by volatilization and leaching. This study aimed to evaluate the effects of urea stabilized with urease inhibitor (UI) and nitrification inhibitor (NI) compared to conventional urea applied at three different schedules, on corn grain yield and the dynamics of inorganic nitrogen on an Amazonian Cerrado soil, Brazil. Two experiments were carried out, one in 2019 and the other one in 2021, in a randomized block design with four replications. Treatments were arranged in a factorial scheme (3 × 3), with three types of urea (urea, U; UI; and NI) and three application schedules (100% at planting, 30% at planting and 70% as topdressing, and 30% at planting and two topdressings with 35% N). In 2019, compared to U and UI, NI increased corn yield when 100% of urea was applied at planting. Regardless of the splitting management, NI ensured the same yields. In 2021, urea splitting was required to improve corn yields, and UI promoted higher yield in all urea application schedule. In 2019 and 2021, both NI and UI, respectively, ensured higher inorganic N levels in the soil, especially after the first topdressing. These N contents are reflected in yield gains. Urea with nitrification or urease inhibitor may be a relevant option for managing nitrogen fertilization in corn crops in the Amazonian Cerrado. Core Ideas Nitrification or urease inhibitors may be an option for managing nitrogen in corn crops in the Amazonian Cerrado. Edaphoclimatic conditions influence the stabilized ureas efficiency in corn cultivation in the Amazonian Cerrado. Urea with urease or nitrification inhibitor ensured higher level of available nitrogen in the soil for plants.

Abstract The latex obtained from Hancornia speciosa Gomes (Mangabeira tree) is widely used in traditional medicine to treat a variety of diseases, including diarrhea, ulcer, gastritis, tuberculosis, acne and warts. In this study, the cytotoxicity and genotoxicity effects of H. speciosa latex on the root meristem cells of Allium cepa were examined. Onion bulbs were exposed to different concentrations of latex and then submitted to microscopic analysis using Giemsa stain. Water was used as a negative control and sodium azide as a positive control. The results showed that, under the testing conditions, the mitotic index (MI) of the onion roots submitted to latex treatment did not differ significantly from the negative control, which suggests that the latex is not cytotoxic. Low incidence of chromosome aberrations in the cells treated with H. speciosa latex was also observed, indicating that the latex does not have genotoxic effect either. The MI and the chromosome aberration frequency responded to the latex concentration, requiring more studies to evaluate the dosage effect on genotoxicity. The results indicate that in tested concentrations H. speciosa latex is probably not harmful to human health and may be potentially used in medicine. Resumo O látex obtido de Hancornia speciosa é amplamente utilizado na medicina popular para tratar uma variedade de doenças, tais como: diarreia, úlcera, gastrite, tuberculose, acne e verrugas. Nesse estudo, foram avaliados os efeitos citotóxicos e genotóxicos do látex de H. speciosa sobre as células meristemáticas das raízes de Allium cepa. Os bulbos das cebolas foram expostos a diferentes concentrações de látex e depois submetidos à analise microscópica usando o corante Giemsa. A água foi usada como controle negativo e a ázida sódica como controle positivo. Os resultados mostraram que o índice mitótico (IM) das raízes de cebola submetidas ao tratamento com látex, nas condições testadas, não diferiram significativamente do controle negativo, e sugerem que o látex não é citotóxico. Também foi observada uma baixa incidência de aberrações cromossômicas nas células tratadas com látex de H. speciosa, o que sugere que o látex também não possui efeito genotóxico. O IM e a frequência de aberrações cromossômicas foram dependentes da concentração de látex. Outros estudos devem ser realizados para avaliar o efeito da dose na genotoxidade. Os resultados indicam que o látex de mangabeira, nas concentrações testadas, provavelmente não é danoso para saúde humana e pode ter potencial para ser usado na medicina.

The aim of this study was to carry out a floristic survey of aquatic macrophytes in the municipality of Chapadinha, eastern Maranhão, and classify their biological forms. The study was done between September 2021 and September 2022. A total of 31 families, 49 genera and 72 species of aquatic macrophytes were catalogued, of which 65 are angiosperms. Among them, Bacopa stricta (Plantaginaceae), Staurogyne diantheroides (Acanthaceae), and Xanthosoma aristeguietae (Araceae) are new records for the flora of Maranhão, with the last two new records for Northeast Brazil. The richest family was Cyperaceae, with 11 species, followed by Plantaginaceae (seven taxa), Fabaceae (five taxa) and Lentibulariaceae (five taxa). Six biological forms were recorded, amphibious (27 taxa) and emergent (26 taxa) being the most common. The aquatic environments of Chapadinha are home to a considerable number of species, families, and life forms of macrophytes. The results show that due to the lack of surveys, evidenced by the new records presented, the state aquatic flora is still underestimated. Further studies in poorly explored areas are suggested, especially in the eastern part of the state, to improve understanding of species richness.

The shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora.

Maintaining plant biodiversity and important ecosystem services depend on the species' ability to survive and disperse after anthropogenic disturbance, loss of natural habitat, and fragmentation. The Cerrado, one of the main biodiversity conservation hotspots in the world, loses natural habitat at a very high rate and suffers from disturbances generated by land use and advancement of the agricultural frontier. Given the need to generate knowledge about land use in Cerrado biome, this study aimed to evaluate if the anthropogenic disturbance alters biodiversity indexes and the capacity to store biomass of these savanna. We installed a permanent plot (20 m × 50 m) inside each study fragment and assessed the intensity of local disturbances such as cattle grazing, earthworm extraction, Caryocar fruit harvesting, and fire. To measure habitat loss and fragmentation, we used configuration and composition metrics in local and landscapes scales. Cattle grazing caused a loss of taxonomic and phylogenetic diversity, while fragment size and Cerrado cover in landscape increased phylogenetic diversity. The patch density, shape complexity and edge density in the landscapes also had a negative influence on phylogenetic diversity. Landscapes with more Eucalyptus sp. plantation area had lower phylogenetic diversity. In addition, the percentage of Cerrado in the landscape had a negative influence on biomass while the number of patches had a positive influence. Thus, we conclude that anthropogenic disturbances in the Cerrado generates loss of taxonomic, phylogenetic diversity and alters biomass stock patterns.