Changes in vegetation cover and tree biodiversity of wetland ecosystems of Ngumburuni Forest Reserve, Rufiji District, Coast Region, Tanzania

Abstract

A Study on the changes in vegetation cover and tree biodiversity of the wetland ecosystems of Ngumburuni forest reserve in Rufiji district was carried out during the period of September 2006 to March 2007 to determine the status of vegetation cover, underlying causes upon its changes and appropriate measures which could be used to stop further degradation of the tree biodiversity within wetland ecosystems. The study was conducted in three closest villages to the forest namely: Umwe north, Mkupuka and Mangwi, whereby sociological information pertaining to uses and threats of forest resources were obtained by using structured questionnaires and focused group interviews. Trees inventory data was collected from a total of 44 sampling plots laid on wetland patches. Finally, a trend of changes in vegetation cover was determined by using Landsand TM satellite images of the years: 1985, 1995 and 2004. The results from this study revealed that the major causes of changes in vegetation cover and tree biodiversity in Ngumburuni forest reserve were the existence of several forest management practices such as shifting cultivation, logging and charcoaling. Similarly, forest inventory data indicated that, there is imbalance of trees species diversity between undisturbed and disturbed forest areas. The results of GIS analysis revealed that there is vegetation cover change in Ngumburuni forest reserve. The changes were more pronounced in the period 1995 to 2004 compared to the period 1985 to 1995. To reduce further degradation of the tree biodiversity within the wetland ecosystem, several measures were suggested such as: command and control approach, establishment of alternative income generating activities and community awareness. In addition to this, it is recommended that, further studies ii should be carried out to determine alternative means of household income to community members instead of the current dependence on forest products and cashewnut crop.