Agroforestry Practices and Woody Species Diversity in Host Communities of Okomu National Park, Edo State, Nigeria

Abstract

Agroforestry is a sustainable land use alternative for conserving trees outside forests. The agroforestry practices and diversity of woody species in the host communities of Okomu National Park (ONP), Edo State was investigated. The study involved the selection of four communities (10% of 42 communities) based on proximity to the national park boundary and extent of agroforestry. The predominant farming practices engaged in by the farmers were identified and three major ones were selected for the woody species inventory. Three farms of the predominant farming systems identified were randomly selected from each community and used as sample plots, amounting to a total of 12 plots (farms). Each of the farms selected was assessed for farm size, types of trees/shrubs, agroforestry methods. The agroforestry practices by the farmers were assessed by visual observation of the diversity, arrangement of woody species. Total enumeration and identification of all live woody species on each farm was conducted and classified into families and some diversity indicators employed to analyze species diversity. The results revealed that all four communities surveyed were actively involved in traditional agroforestry: scattered farm tree system, tree crop farming under shade of trees, home gardens and boundary tree planting systems. The highest density of woody species recorded in Mile 3 community (517 trees/shrubs H-1) and Mahokhioba community recorded the least value of 134 trees/shrubs H-1. Moraceae and Euphorbiaceae were the most dominant families recorded in the study while Iguowan had the highest Shannon index (H) of 2.99. The high population of Eleais guineensis, Cola acuminata, Gmelina arborea and a host of others implies that the farmers deliberately cultivated and retained the species for their economic values thereby ensuring the species sustainability. This strategy can be explored for conserving trees in areas outside protected forests.