Levantamento da comunidade de macroinvertebrados bentônicos em lavouras de arroz irrigado.

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Tipos funcionais de plantas em pastagem natural na depressão central - RS.

O presente estudo foi conduzido na Estação Experimental Agronômica da Faculdade de Agronomia da Universidade Federal do Rio Grande do Sul em uma área de três hectares de campo natural, durante o período de dezembro/2002 a outubro 2003, com os objetivos de identificar e caracterizar a freqüência de ocorrência dos tipos funcionais de plantas (TFs) que foram obtidos a partir da descrição de atributos morfológicos, e caracterizar o comportamento alimentar de bovinos. Para a medição dos atributos, foram marcadas 30 unidades amostrais permanentes compostas de cinco quadros contíguos de 0,20 m x 0,20 m cada. Os resultados mostraram em relação à descrição da comunidade um subconjunto ótimo dos atributos propagação vegetativa, especializações morfológicas de defesa da lâmina foliar, biomassa da parte aérea, altura máxima da última folha expandida e porcentagem de biomassa acima da altura onde ocorre a maior concentração de biomassa fotossintetizante, os quais definiram cinco TFs em relação a inclinação do terreno e o pastejo. O tempo de pastejo aumentou à medida que aumentaram os dias de ocupação da área e que diminuiu a disponibilidade de forragem e altura das plantas. A análise dos resultados mostrou a possibilidade de se obter informações para o monitoramento da comunidade vegetal que visem potencializar a produção do agroecossistema

Tipos funcionais de plantas em resposta a variável ambiental relevo em pastagem natural na depressão central do RS.

O estudo foi realizado na Estação Experimental Agronômica da Faculdade de Agronomia da Universidade Federal do Rio Grande do Sul em uma área de aproximadamente três hectares, durante o período de dezembro/2002 a fevereiro de 2003, com o objetivo de identificar e caracterizar a freqüência de ocorrência dos tipos funcionais (TFs) em uma pastagem natural que foi obtida a partir da descrição de atributos morfológicos. Para a medição dos atributos, foram marcadas 30 unidades amostrais permanentes compostas de cinco quadros contíguos de 0,20 m x 0,20 m cada. Os resultados observados em relação à descrição da comunidade mostraram um subconjunto ótimo dos atributos (porcentagem de folhas senescentes, altura máxima, propagação vegetativa, largura da lâmina foliar e força de tensão da lâmina foliar), os quais definiram dois tipos funcionais (TFs). No TF1 foram incluídas as populações com maior porte, mais folhas senescentes e mais resistentes à ruptura. No TF-2 foram consideradas as populações com folhas mais largas, menos senescentes e menos resistentes. A partir destas informações pode-se inferir que a caracterização da vegetação embasada na definição de atributos morfológicos apresenta pertinência e representa uma contribuição para estabelecer indicadores que permitam o melhoramento da vegetação e incrementos da produtividade animal

Joining forces to strengthen community seedbanks worldwide

Community seedbanks and emerging networks of community seedbanks contribute to the conservation and sustainable use of plant genetic resources for food and agriculture. Community seedbanks can secure improved access to and availability of diverse, locally adapted crops and varieties and enhance related indigenous knowledge and skills in plant management including seed selection, treatment, storage, multiplication and distribution. Two events were held in July 2018 in Rome, Italy to bring together representatives of organizations supporting community seedbanks from Africa, Asia, Europe and Latin America. This brief presents achievements, challenges, lessons learned and new opportunities in their countries and reflects on prospects of community seedbanks and their networks

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Global beta-diversity of angiosperm trees is shaped by Quaternary climate change

As Earth's climate has varied strongly through geological time, studying the impacts of past climate change on biodiversity helps to understand the risks from future climate change. However, it remains unclear how paleo-climate shapes spatial variation in biodiversity. Here, we assessed the influence of Quaternary climate change on spatial dissimilarity in taxonomic, phylogenetic, and functional composition among neighboring 200-kilometer cells (beta-diversity) for angiosperm trees worldwide. We found that larger glacial-interglacial temperature change was strongly associated with lower spatial turnover (species replacements) and higher nestedness (rich-ness changes) components of beta-diversity across all three biodiversity facets. Moreover, phylogenetic and functional turnover was lower and nestedness higher than random expectations based on taxonomic beta -di-versity in regions that experienced large temperature change, reflecting phylogenetically and functionally se-lective processes in species replacement, extinction, and colonization during glacial-interglacial oscillations. Our results suggest that future human-driven climate change could cause local homogenization and reduction in taxonomic, phylogenetic, and functional diversity of angiosperm trees worldwide

Climatic and soil factors explain the two-dimensional spectrum of global plant trait variation

Plant functional traits can predict community assembly and ecosystem functioning and are thus widely used in global models of vegetation dynamics and land–climate feedbacks. Still, we lack a global understanding of how land and climate affect plant traits. A previous global analysis of six traits observed two main axes of variation: (1) size variation at the organ and plant level and (2) leaf economics balancing leaf persistence against plant growth potential. The orthogonality of these two axes suggests they are differently influenced by environmental drivers. We find that these axes persist in a global dataset of 17 traits across more than 20,000 species. We find a dominant joint effect of climate and soil on trait variation. Additional independent climate effects are also observed across most traits, whereas independent soil effects are almost exclusively observed for economics traits. Variation in size traits correlates well with a latitudinal gradient related to water or energy limitation. In contrast, variation in economics traits is better explained by interactions of climate with soil fertility. These findings have the potential to improve our understanding of biodiversity patterns and our predictions of climate change impacts on biogeochemical cycles