14 research outputs found

    Crescimento, defesas e herbivoria em folhas jovens de Qualea parviflora (Vochysiaceae) em três diferentes habitats de Cerrado

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    Insect herbivory is strongly influenced by the properties of their host leaves. Otherwise, such influence may be mediated by the environment in which the host plant is found. We examined three characteristics that may influence insect herbivory on young leaves of Qualea parviflora Mart. (Vochysiaceae), a widespread tree of the Brazilian Cerrado: leaf expansion rate, sclerophylly (leaf toughness), and tannin concentration during four consecutive months. Herbivory rates were measured on four marked intact leaves in five trees in three different physiognomies of the Cerrado biome: campo sujo (grassland), cerrado sensu stricto (savanna), and cerradão (woodland). Sclerophylly was higher in February while the highest concentration of tannins occurred in November but no variation in the rates of herbivory among months and physiognomies was found. A tendency of higher mean leaf growth rates was observed in the “cerradao” (1.03%) and “cerrado” (1.04%) in comparison with the campo sujo trees (0.86%). Higher sclerophylly and lower expansion rates and leaf size were observed in trees of the campo sujo. There was a tendency for higher herbivory rates in cerrado (10.5%), where the leaves showed lower concentration of tannins (1.5%) than in cerradão (2.1%). New leaves of Q. parviflora showed higher tannins concentration and lower damage than fully expanded leaves. Final leaf area explained 24% of the variation in total herbivory. Leaf size and associated nutritional factors exerted stronger influence on herbivory than defensive compounds on young leaves of Q. parviflora. Key words: Cerrado, leaf age, leaf growth, Neotropical savanna, plant defenses, sclerophylly.A herbivoria por insetos é fortemente influenciada pelas propriedades das folhas hospedeiras. No entanto, esta influência pode ser mediada por condições ambientais do habitat da planta. Neste estudo foram examinadas três características que podem influenciar a herbívora por insetos em folhas jovens de Qualea parvifl ora Mart. (Vochysiaceae), uma árvore comum do Cerrado brasileiro: taxa de expansão foliar, esclerofilia (rigidez foliar) e concentração de taninos. As taxas de herbívora foram medidas em quatro folhas intactas de cinco árvores em três diferentes fitofisionomias do bioma Cerrado: “campo sujo”, “cerrado sensu stricto” e “cerradão”. A esclerofilia foi maior em Fevereiro enquanto altas concentrações de taninos ocorreram em Novembro. No entanto, não foi observada variação nas taxas de herbívora entre os meses e entre fisionomias. Uma tendência em maiores taxas de crescimento foliar foi observada em árvores ocorrentes no “cerradão” (1,03%) e no “cerrado” (1,04%) em comparação com as ocorrentes no “campo sujo” (0,86%). Maiores valores de esclerofilia, baixas taxas de expansão foliar e menor tamanho foliar foram observadas no “campo sujo”. Houve uma tendência em altas taxas de herbívora no “cerrado” (10,5%), onde as folhas apresentaram concentrações de taninos mais baixas (1,5%) que no “cerradão” (2,1%). As folhas jovens de Q. parviflora apresentaram maiores concentrações de taninos e menor dano por herbívora que folhas maduras. A área foliar final explicou 24% da variação da herbívora total. O tamanho das folhas e fatores nutricionais associados exerceram influências mais fortes na herbívora que a concentração de compostos de defesa em folhas jovens de Q. parviflora. Palavras-chave: Cerrado, crescimento foliar, defesa de plantas, esclerofilia, idade foliar, savana neotropical

    Biome awareness disparity is BAD for tropical ecosystem conservation and restoration

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    We introduce the concept of Biome Awareness Disparity (BAD)—defined as a failure to appreciate the significance of all biomes in conservation and restoration policy—and quantify disparities in (a) attention and interest, (b) action and (c) knowledge among biomes in tropical restoration science, practice and policy. By analysing 50,000 tweets from all Partner Institutions of the UN Decade of Ecosystem Restoration, and 45,000 tweets from the main science and environmental news media world-wide, we found strong disparities in attention and interest relative to biome extent and diversity. Tweets largely focused on forests, whereas open biomes (such as grasslands, savannas and shrublands) received less attention in relation to their area. In contrast to these differences in attention, there were equivalent likes and retweets between forest versus open biomes, suggesting the disparities may not reflect the views of the general public. Through a literature review, we found that restoration experiments are disproportionately concentrated in rainforests, dry forests and mangroves. More than half of the studies conducted in open biomes reported tree planting as the main restoration action, suggesting inappropriate application of forest-oriented techniques. Policy implications. We urge scientists, policymakers and land managers to recognise the value of open biomes for protecting biodiversity, securing ecosystem services, mitigating climate change and enhancing human livelihoods. Fixing Biome Awareness Disparity will increase the likelihood of the United Nations Decade on Ecosystem Restoration successfully delivering its promises.This article also appears in: Cross Society Special Feature on the Decade of Ecosystem Restoration.DATA AVAILABILITY STATEMENT: Data available via the Dryad Digital Repository https://doi.org/10.6084/m9.figshare.16778200.v1 (Silveira et al., 2021).Conselho Nacional de Desenvolvimento Científico e Tecnológico; Fundação de Amparo à Pesquisa do Estado de Minas Gerais; CNPq; CAPES; NERC-FAPESP; USDA-NIFA Sustainable Agricultural Systems; USDA-NIFA McIntire-Stennis Project; National Science Foundation.http://www.wileyonlinelibrary.com/journal/jpe2022-10-15hj2022Zoology and Entomolog

    How much leaf area do insects eat? A data set of insect herbivory sampled globally with a standardized protocol

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    Herbivory is ubiquitous. Despite being a potential driver of plant distribution and performance, herbivory remains largely undocumented. Some early attempts have been made to review, globally, how much leaf area is removed through insect feeding. Kozlov et al., in one of the most comprehensive reviews regarding global patterns of herbivory, have compiled published studies regarding foliar removal and sampled data on global herbivory levels using a standardized protocol. However, in the review by Kozlov et al., only 15 sampling sites, comprising 33 plant species, were evaluated in tropical areas around the globe. In Brazil, which ranks first in terms of plant biodiversity, with a total of 46,097 species, almost half (43%) being endemic, a single data point was sampled, covering only two plant species. In an attempt to increase knowledge regarding herbivory in tropical plant species and to provide the raw data needed to test general hypotheses related to plant–herbivore interactions across large spatial scales, we proposed a joint, collaborative network to evaluate tropical herbivory. This network allowed us to update and expand the data on insect herbivory in tropical and temperate plant species. Our data set, collected with a standardized protocol, covers 45 sampling sites from nine countries and includes leaf herbivory measurements of 57,239 leaves from 209 species of vascular plants belonging to 65 families from tropical and temperate regions. They expand previous data sets by including a total of 32 sampling sites from tropical areas around the globe, comprising 152 species, 146 of them being sampled in Brazil. For temperate areas, it includes 13 sampling sites, comprising 59 species

    Restoration of open ecosystems in the face of climate change

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    Open ecosystems occur all around the world in various forms including temperate and tropical grasslands, savannas, shrublands, heathlands, among others. They are home to unique biodiversity, provide key ecosystem services and sustain traditional livelihoods of nearly two billion people. In the face of ongoing climate change, practitioners aiming to restore open ecosystems need the support of the scientific community more than ever. The aim of this Special Issue (SI) is to provide an attention-grabbing collection of high-quality publications addressing the growing challenges of open ecosystems restoration. The SI contains 14 papers that fill various, often interdisciplinary knowledge gaps. Three papers deal with the challenges of identifying the right target states, including the genetic composition of constituting plant species, for restoration under changing environmental conditions and competing stakeholder interests. Five papers advance our understanding on the appropriate timing and methodological toolkit to actively ignite re-assembly of the target plant communities, while two papers focus on situations where spontaneous processes can still also be relied on. The interaction of open ecosystems health and recovery with higher trophic levels, particularly grazers, is also discussed in three papers. Finally, a review paper systematically identifies further knowledge gaps, such as the role of soil microbes in grassland recovery and makes clear guidelines how to fill them. Due to the variety of topics and the rigorous content, this SI provides strong support for open ecosystems restoration policy and practice under the UN Decade on Ecosystem Restoration and beyond

    A simple standardized protocol to evaluate the reliability of seed rain estimates

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    International audienceSeed dispersal has key implications for community dynamics and restoration ecology. However, estimating seed rain (the number and diversity of seeds arriving in a given area) is challenging, and the lack of standardization in measurement prevents cross-site comparisons. Seed trap effectiveness and accuracy of seed sorting methods are key components of seed rain estimates in need of standardization. We propose and describe a standardized protocol for evaluating the effectiveness of two seed trap types (sticky and funnel traps), and the accuracy of a seed sorting method. We used widely available seeds (arugula, quinoa, sesame and sunflower) to produce a gradient of seed size, weight and color. Proof-of-concept was tested in a tropical grassland, where traps were set for 30 days. Our results suggest that we underestimate dispersal of small seeds (less than 2mm width) that can be easily mistaken for debris and soil particles or that fail to adhere to sticky traps. Seeds on sticky traps may be more vulnerable to removal by wind and rain, whereas seeds in funnel traps are more susceptible to decay. We found no evidence of observer bias on seed sorting for funnel trap samples. However, accuracy on seed sorting for funnel trap samples tended to decline for seeds with less than 2mm width, suggesting a size-dependence in seed retrieval success. Our standardized protocol addressing trap effectiveness and seed sorting methods will increase reliability of data obtained in seed rain studies in grasslands and allow more reliable comparisons between datasets

    Fenologia reprodutiva e vegetativa de arbustos endêmicos de campo rupestre na Serra do Cipó, Sudeste do Brasil

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    Os Campos rupestres têm destaque no cenário mundial da conservação por sua enorme riqueza em espécies e alta taxa de endemismo. É considerado um ecossistema ameaçado devido à intensa e progressiva descaracterização que vêm sofrendo pela ação antrópica. O objetivo deste estudo foi descrever os padrões fenológicos reprodutivos e vegetativos em seis espécies arbustivas endêmicas dos campos rupestres da Cadeia do Espinhaço, simpátricas na Serra do Cipó, Minas Gerais, e testar a relação entre suas fenofases e a estacionalidade climática. Esperamos que as espécies tenham suas fenofases fortemente relacionadas às variações entre as estações seca e úmida. As observações fenológicas foram conduzidas mensalmente nas fenofases reprodutivas (flor, fruto e dispersão) e vegetativas (queda de folhas e brotamento). De acordo com a combinação dos padrões fenológicos reprodutivos, vegetativos e sazonalidade, foi possivel distinguir quatro estratégias fenológicas para as seis espécies avaliadas. Dessa forma, o presente estudo mostrou uma grande diversidade de padrões fenológicos, mesmo considerando o pequeno número de espécies amostradas. Por outro lado, em todas as espécies as fenofases reprodutivas apresentaram um padrão significativamente sazonal, com alta concentração de espécies reproduzindo em uma dada estação do ano, sugerindo uma importância destacada da sazonalidade do clima na definição dos padrões fenológicos em campos rupestres

    Ex situ conservation of threatened plants in Brazil: a strategic plan to achieve Target 8 of the Global Strategy for Plant Conservation

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    Abstract With increasing rates of habitat destruction and species loss, ex situ conservation is gaining global momentum and reluctance in relying on ex situ conservation is rapidly giving way to a more optimistic, strategic view. Target 8 of the Global Strategy of Plant Conservation calls for at least 75 percent of threatened plant species in accessible ex situ collections, preferably in the country of origin, and 20 percent of them included in recovery and restoration programs. Here, we provide updated information on Brazil's progress towards Target 8 through a nationwide examination of how many threatened species were conserved in ex situ collections in Brazil. Our data comprised whole plants (living collections), seed (seed banks) and tissue cultures (in vitro). Of the 2,113 threatened species, at least 452 (21.4%) species were conserved in ex situ collections, an increase in 4% of living organisms and 96% of seeds when compared to a previous assessment. Since it is unlikely Brazil will achieve Target 8 by 2020, we also discuss public policies and strategies to help overcome key bottlenecks preventing its achievement and propose revised goals for the GSPC 2020-2030
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