Instituto de Pesquisa Ambiental da Amazônia (IPAM), Rua Horizontina 104, Centro, Canarana, MT, 78640-000, Brazil.
Programa de Pós-Graduação em Ecologia e Conservação, Universidade do Estado de Mato Grosso (UNEMAT), Campus de Nova Xavantina, Rua Prof. Dr. Renato Figueiro Varella, Caixa Postal 08, Nova Xavantina, MT, 78690-000, Brazil.
Sci Rep. 2023 Aug 1;13(1):12454. doi: 10.1038/s41598-023-39510-x.
Tropical forest fragmentation from agricultural expansion alters the microclimatic conditions of the remaining forests, with effects on vegetation structure and function. However, little is known about how the functional trait variability within and among tree species in fragmented landscapes influence and facilitate species' persistence in these new environmental conditions. Here, we assessed potential changes in tree species' functional traits in riparian forests within six riparian forests in cropland catchments (Cropland) and four riparian forests in forested catchments (Forest) in southern Amazonia. We sampled 12 common functional traits of 123 species across all sites: 64 common to both croplands and forests, 33 restricted to croplands, and 26 restricted to forests. We found that forest-restricted species had leaves that were thinner, larger, and with higher phosphorus (P) content, compared to cropland-restricted ones. Tree species common to both environments showed higher intraspecific variability in functional traits, with leaf thickness and leaf P concentration varying the most. Species turnover contributed more to differences between forest and cropland environments only for the stem-specific density trait. We conclude that the intraspecific variability of functional traits (leaf thickness, leaf P, and specific leaf area) facilitates species persistence in riparian forests occurring within catchments cleared for agricultural expansion in Amazonia.
农业扩张导致的热带森林破碎化改变了剩余森林的小气候条件，从而影响了植被的结构和功能。然而，对于破碎化景观中树种内部和树种之间的功能性状变异性如何影响和促进物种在这些新环境条件下的生存，我们知之甚少。在这里，我们评估了南亚马孙地区 6 个农田流域内的河岸林（农田）和 4 个森林流域内的河岸林（森林）中树种功能性状的潜在变化。我们在所有地点共采样了 123 个物种的 12 个常见功能性状：64 个在农田和森林中都有，33 个仅在农田中，26 个仅在森林中。我们发现，与农田限制的物种相比，森林限制的物种具有更薄、更大和更高磷（P）含量的叶子。在两种环境中都常见的树种在功能性状上具有更高的种内变异性，其中叶片厚度和叶片 P 浓度的变化最大。仅对于茎比密度性状，物种周转率对森林和农田环境之间的差异贡献更大。我们的结论是，功能性状（叶片厚度、叶片 P 和比叶面积）的种内变异性有助于在亚马孙地区为农业扩张而清理的流域中存在的河岸林中物种的生存。
