Understory and Soil Macrofauna Diversity under the Three Young Native Species and Acacia crassicarpa in a Drained Peatland of Pelalawan-Riau, Indonesia

Balai Litbang Teknologi Serat Tanaman Hutan, Riau 28401, Indonesia

Abstract

Most studies mentioned that Acacia crassicarpa belongs to invasive species that could threat the native biodiversity. To respond that issue, we conducted a study that covers the understory and soil macrofauna diversity of three native tree species, namely mahang (Macaranga pruinosa), skubung (Macaranga gigantea) and geronggang (Cratoxylum arborescens) and an exotic species namely krassikarpa in a drained peatland in Pelalawan, Riau. The observation of understory vegetation under each studied species was undertaken by using 2 x 1 m plots. Furthermore, the structure of macrofauna was observed by pitfall trap methods. Results revealed that there were two fern species namely Neprolephis biserrata and Stenochlaena palustris that dominated the understory vegetation in namely mahang (Macaranga pruinosa), skubung (Macaranga gigantea) and geronggang (Cratoxylum arborescens). The diversity index in vegetation structure among those four tree species was insignificantly varied. Moreover, the percentage of understory coverage under A. crassicarpa was significantly higher than that under all native tree species. On the other hand, Formicidae and Rhinotermitidae were dominant in skubung and krassikarpa. Meanwhile, Formicidae and Blattidae were high in mahang and geronggang. Furthermore, diversity index of macrofauna were significantly low at krassikarpas`s understory compare to other three native species. This study suggested that the introduction of krassikarpa affect the biodiversity.