Linking forest transition, plant invasion and forest succession theories: socioeconomic drivers and composition of new subtropical andean forests

JIMENEZ, YOHANA GISELL; ARÁOZ, EZEQUIEL; GRAU, H. RICARDO; PAOLINI, LEONARDO

LANDSCAPE ECOLOGY

SPRINGER

Año: 2021 vol. 36 p. 1161 - 1176

0921-2973

The patterns and causes of forest transitionhave been extensively studied, identifying socioeconomicdrivers of land use deintensification andthe associated forest expansion. However, most studiesdo not take into account the origin of the dominantspecies of new forests (i.e. native or exotic), whichaffects biodiversity and the provision of ecosystemservices. Objectives We develop a framework integratingforest transition, forest succession and biologicalinvasion theories to identify the socio-environmentalconditions that facilitate different pathways of spontaneousforest transitions in a subtropical mountainbasin.Methods We used Landsat images and Randomforest classifier to detect land cover changes over30 years (1988?2017). We used generalized additivemodels to identify socioeconomic and biophysicalvariables associated with expansion of native andexotic-dominated forests.Results Expanding native forests are scatteredthroughout the whole basin under a broad spectrumof socioeconomic and environmental conditions. Incontrast, the new forests dominated by exotic specieswere aggregated around their focal introduction areasand their expansion was associated with accessibilityand specific land uses (livestock or residential use).Conclusions Understanding the pathways of alternativeforest transition involves the integration of landscience, forest succession theory and invasion ecology.Land science explains the availability of sites tobe reforested. The species composition of new forestsdepends on the availability of propagules, dispersalagents and competitive relationships between species(forest succession theory). Invasion ecology explainsthe role of introduction areas (which are oftenassociated with residential use) of exotic species inthe successional process.