Herbaceous Species Diversity in Kanawa Forest Reserve (KFR) in Gombe State, Nigeria

Abstract

The study was conducted between 2009 and 2011 in Kanawa Forest Reserve (KFR) in order to determine the impact of anthropogenic pressures and environmental changes of the herbaceous species. The project area was divided into six sites following the variety of land forms in the forest and three transects measuring 100m were laid within each site. Point Centered Quarter (PCQ) sampling method was used. Data obtained were analyzed for relative density, relative frequency, and importance value index. A total of (35) species were identified in KFR out of which 16 species belonged to grasses within three families and 19 genera. The family Poaceae had the highest number, 10 species, the Cyperaceae had 5 species, while the Typhaceae had only l. 19 species belonged to forbs within fourteen families and 16 genera. The families Asteraceae and Leguminosae: Fabaceae had 3 species each: Rubiaceae had 2 species each. Acanthaceae, Capparidaceae, Euphorbiaceae, Nyctaginaceae, Zygophyllaceae, Portulacaceae, Polygonaceae, Solanaceae, Onagraceae, Labiatae and Commelinaceae all had 1 species each. Simpson’s index of diversity was 0.998 and Shannon-Wiener Index was 4.57. This condition indicates complex vegetation. Chi square and its related statistics showed significant positive associations between site I and IV, lI and IV, V and VI. Only site I and IV, II and IV, V and VI were significantly negatively associated at (P < 0.05). The species with the lowest importance value indices were:- Pennisetum pedicellatum, Polygonum senegalense, Vetiveria nigrinata, Zornia glochidiata. These plants therefore require more efforts on conservation.