Atributos foliares de espécies do semiárido como fatores regulatórios para invertebrados aquáticos

Abstract

Leaf traits are directly linked to the life history of the organism. The amount of leaf N, the phenol content, or even the hardness of the leaves are important determinants for the survival and development of the plant, and, moreover, can directly influence ecosystem processes such as decomposition of organic matter. The amount and disposal of chemical and physical constituents of the leaf can determine its quality to the organisms responsible for accelerating the decomposition process, such as benthic invertebrates. Thus, the decay rates may be higher or lower, with direct effects on the cycling of matter within the ecosystem. In streams w ith riparian vegetation, leaf decomposition is an important process for input of matter and energy in the aquatic ecosystem. In semi-arid regions, plant species commonly need to develop strategies to mitigate the effects of drought and herbivores, such as the decrease in leaf nitrogen content, or the accumulation of secondary compounds in their leaves, which reduces its nutritional quality for invertebrates. The decrease in leaf quality of the riparian zone may have direct effects on the energy balance of aquatic systems. In addition, semi-arid regions have few papers related to the process of decomposition in aquatic ecosystems, which compromises the knowledge about an important part of cycling of organic matter in riparian vegetation regions. Among the questions on the subject, our goal with this study was to evaluate the effect of leaf traits of common species in semiarid regions on the colonization of invertebrates during decomposition in a stream. Based on the results obtained, we can characterize in a pioneering way how the process of leaf decomposition and colonization by invertebrates occurs in a stream in the semiarid.