Distribución espacial y tasa de invasión de flora exótica en la Reserva Natural de Vaquerías, Provincia de Córdoba (Argentina)

Abstract

Nos propusimos usar como herramienta imágenes satelitales de alta resolución a fin de concretar los siguientes objetivos: 1. Determinar la configuración espacial actual (área, forma y contigüidad) de las coberturas de flora exótica invasora Siempre verde, Acacia negra y Crataegus. y 2. Estimar la tasa de invasión anual de las tres especies exóticas invasoras (período 2005-2012).

This study was carried out in the Vaquerias Nature Reserve owned by the National University of Cordoba, located in the Department of Punilla, Province of Cordoba-Argentina, during the years 2012-2013. The objective was to obtain information about the process and state of invasion of exotic flora in the reserve and its buffer zone. A baseline survey at landscape scale was undertaken, to make appropriate management decisions for the control of these invasive species. The current spatial configuration (area, shape, and contiguity) of the following species was determined: Ligustrum lucidum (Glossy privet), Gleditsia tricanthos (Honey locust) and Pyracantha coccinea (Scarlet firethorn). The rate of invasion was estimated and priority actions for the management of invasive exotic plants are proposed. The discrimination of plant cover was performed with a SPOT-5 merged satellite image (spatial resolution 2.5 m) using the Parallelepiped classification with an accuracy of 83.84% and an index Kappa of 0.80. Of the 522 ha that form the reserve, invasive alien flora covers a total area of 135.6 ha, distributed as follows: 20.9 ha of Scarlet firethorn, 39.5 ha of Glossy privet and 75.2 ha of Honey locust. In the buffer zone, the quadrants North, South and West represent the areas of greatest risk of invasion to the reserve. The areas dominated by invasion are: roads, trails, streams, creeks, and burnt areas. The invasion rate between 2005 and 2012 for Scarlet firethorn was 0.03 ha/year and the average increase per year was 49.16%. For the mixed association of Glossy privet and Honey locust the rate of invasion was 0.031 ha/year and the average increase per year was 4.73%.