Leaf litter decomposition from native and non-native species in a freshwater forested wetland of Chile

Abstract

Decomposition of leaf litter is a fundamental process for the functioning of forested wetlands. The rapid increment of forest plantations has involved a greater contribution of leaf litter of exotic origin to these ecosystems. The decomposition rate between leaf litter of native and exotic origin in a forested wetland of the Mediterranean zone of Chile was compared, as well as the contribution of bacteria and macroinvertebrate to this process. It was determined that the decomposition rate of the leaf litter presented signifi cant differences (p < 0.05) between species, being faster in those of non-native origin. This could be due to differences in ecophysiological aspects of the leaves like the presence of chemical compounds such as waxes or oils. Both analyzed communities were relevant in the studied process. However, bacteria contributed mostly to the decomposition of both types of leaves. The implications of the physical and chemical characteristics of the leaves and the water on the processing of the foliar material are discussed. KEYWORDS:Allochthonous detritus, bacteria, lentic ecosystem, macroinvertebrates. RESUMENEn los humedales boscosos, la descomposición de la hojarasca es un proceso fundamental para su funcionamiento. El rápido incremento de las plantaciones forestales ha implicado un mayor aporte de hojarasca de origen exótico a estos ecosistemas. Se comparó la tasa de descomposición entre hojarasca de origen nativo y exótico en un humedal boscoso de la zona Mediterránea de Chile, así como la contribución de las bacterias y macroinvertebrados a este proceso. Se determinó que la tasa de descomposición de la hojarasca presentó diferencias signifi cativas entre las diferentes especies (p < 0,05), siendo más rápido en especies de origen exótico. Esto podría ser dado por diferencias en algunos aspectos ecofi siológicos de las hojas como la presencia de compuestos químicos tales como ceras o aceites. Ambas comunidades analizadas fueron relevantes en el proceso estudiado. Sin embargo, las bacterias contribuyeron mayormente a la descomposición de ambos tipos de hojas. Se discuten las implicaciones de las características físicas y químicas de las hojas y el agua en el procesamiento del material foliar.

First Report of Arthropod Fauna in Flooded Plains of Northern Patagonia (38° S, Araucania Region Chile)

“…Chile contains numerous kinds of shallow inland water bodies with diff erent types of biotic components, mainly submerged vegetation, called locally vega, mallín or pitranto (Correa-Araneda et al, 2011. Th ey can sustain broad aquatic invertebrate communities, mainly consisting of insects and crustaceans (Correa-Araneda et al, 2017 a, b;Gomez-Capponi et al, 2017). Some of these water bodies are habitats of endemic local crayfi shes of the genera Parastacus and Virilastacus, various species of which are widely distributed throughout central Chile (32-38° S).…”