Short-term effects of a revegetation program on the Orthopteran diversity in oak forests of the southern Iberian Peninsula.

Abstract

Orthopterans are insects closely linked to vegetation as primary consumers as well as for other biological processes such as oviposition and development. This research aims to assess the effect of a revegetation program that began in 2007 in the compensation area linked to the construction of the Breña II dam on Orthopteran diversity within several different human-created and natural habitats (forest-islands, hedges, and river-copses). We assessed vegetation and orthopteran communities during monthly sampling performed during March through September 2011. For the Orthopterans, two replicates per habitat type were sampled in each of the eight selected sampling plots, providing 48 observations per environment per month. To characterize the structure of communities, diversity, dominance, and evenness were calculated, and posterior comparisons were made using bootstrapping analysis. Additionally, rarefaction curves were obtained. We found large between-habitat differences in plant abundance but smaller differences in diversity. The high degree of vegetational homogeneity likely explains the structural similarity among the Orthopteran communities in the different habitats. Although Caelifera were more abundant and diverse in unmanaged biotopes, Ensifera seem to be favored in revegetated areas. Because accurate management requires documenting diversity at the field scale, work like that presented here should increase the efficiency of future assessments of Orthopteran habitat suitability for diversity conservation.