Selective logging in public pine forests of the central Iberian Peninsula: Effects of the recovery process on ant assemblages

Abstract

Pine forests on the northern plateau of the Iberian Peninsula have a long history of use, exploitation, and management. Current management practices consist of selective logging with relatively short periods of time between logging events. The main objective of this study is to detect changes in ant assemblages in the short time periods between selective logging activities. Ants were sampled at 44 sites considering three grouping categories of time periods after the last timber extraction: short (<4. years), medium (4-8. years) and long (>8. years). After selective logging the number of ant species increases as the forest recovers. A look at the differences between the assemblages when the analysis shifts from the species-specific level to functional groups showed differences between the short and long categories. This indicates that in certain circumstances the functional groups may be more informative of the functional restructuring of the ant assemblages in a disturbed habitat. Ant species from three functional groups display significant indicative values (Opportunist, Hot Climate Specialists and Subordinate Camponotini) in the medium- and long-time-after-logging categories: Messor capitatus (HCS) for medium-time category sites; and Aphaenogaster iberica (Op), Camponotus cruentatus (SC) and, Cataglyphis velox (HCS) for long-time category sites. No indicator species were found for the early stages of recovery. This information may also be of interest to managers because it reduces the number of data elements of the recovery status of these forests, and can be translated into monitoring protocols. The continued exploitation of these forests leads to an ant fauna that reflects this change. The results show that ant assemblages need at least 8. years to recover since only after that much time there is an emergence of Subordinate Camponotinae, a behaviorally dominant and low stress-tolerant functional group. This selective logging maintains the relative diversity and structure of ant assemblages