How human-induced transitions from forest to treeless ecosystems affect litter decomposition

HARGUINDEGUY, NATALIA PÉREZ; CINGOLANI, ANA M.; ENRICO, LUCAS; VAIERETTI, MARÍA V.; GIORGIS, MELISA A.; MORENO, MARÍA L.; FALCZUK, VALERIA; GURVICH, DIEGO E.; BERTONE, GUSTAVO A.; DÍAZ, SANDRA M.; CABIDO, MARCELO R.

ECOLOGÍA AUSTRAL

ASOCIACIÓN ARGENTINA DE ECOLOGÍA

Año: 2022 vol. 32 p. 716 - 733

0327-5477

A�������. The transformation of forests to treeless landscapes as a result of disturbances (deforestation transitions) is an ongoing process in many regions of the world. Here we first revise the historical context of these transformations and then, we focus on its consequences for li�er decomposition. We also present a case study, based on four ecosystems of central Argentina (Sub-Andean, Mountain Chaco, Espinal and Arid Chaco), evaluating how deforestation transitions can modify ecosystem decomposition by altering its main controls. Although there is evidence of consequences of deforestation transitions on the local environment for decomposition and on leaf li�er quality it is not clear how those changes would impact the decomposition of natural mixed li�er in the field. In our study case, we show that the deforestation transitions evaluated across four ecosystems resulted in no consistent changes in standard substrate decomposition but a consistent increase in the li�er mixtures’ decomposability and quality. Likely as a consequence of this pa�ern, the loss of trees resulted in a consistent increase in the in situ mixtures decomposition across the ecosystems studied. Beyond our particular findings, our analysis highlights how the accurate prediction of the consequences of deforestation transition on changes in carbon and nutrient cycling needs to understand the behaviour of its controls. Only through this understanding, we will be able to interpret the pa�erns of in situ mixtures decomposition and predict the consequences of deforestation transitions adequately on carbon (C) and nutrient cycling. Additionally, the recent literature, in coincidence with our results, gives evidence that the presence of non-leafy plant debris and local-scale variation in the local environment may play a stronger role than previously thought in C and nutrient cycling