Plant ecology and ethnobotany of two sacred forests (kayas) at the Kenya coast.

Abstract

The coastal forests of Kenya represent a rare and threatened forest type which has over 3,000 plant taxa, of which about 500 are endemic. The patches which comprise this forest type include sacred forests, the kayas, that are rich in biodiversity. The aim of the study report was to investigate the phytosociological relationships in two selected kayas, Mtswakara and Fungo, and the plant utilisation by the people of the Duruma and Giriama tribes who live around these forests. The vegetation was sampled using the phytosociological approach developed by Braun-Blanquet. In kaya Mtswakara 51 relevés of 0.2 ha. were sampled and a total of 317 species from 191 genera in 79 families were recorded, representing 48 tree species, 134 shrubs, 82 herbs, 45 climbers, and 8 epiphytes. In kaya Fungo, 280 species from 213 genera in 74 families, representing 35 tree species, 125 shrubs, 73 herbs, 43 climbers, and 3 epiphytes, were recorded in 54 relevés. TWINSPAN classification of the data indicated the existence of four plant communities and six sub-communities in kaya Mtswakara; and three plant communities, four sub-communities, three stages, three sub-stages and one undetermined vegetation type in kaya Fungo. The phytosociological results indicated that diagnostic species for plant communities are not necessarily the dominant tree species; and interactions of edaphic factors, plant resource extraction, fire and grazing influenced the formation and distribution of vegetation types. The human populations living around the forests depend upon and utilise plant species found in the kayas to meet some of their basic domestic needs and cultural requirements. But, unlike in the past, the council of kaya elders (ngambi) cannot address all the forest management problems, due to factors such as increased disrespect of cultural traditions in the communities, increasing demands of forest plant resources due to population increase, conflicts between local faction groups claiming legitimacy in kaya management and socio-political changes. Surveys conducted in the local markets showed that although forest plants formed a small percentage of the building poles traded, the firewood trade was considerable. In addition to the regular market trade, there is a 'house-to-house' trade conducted by some community members who sell poles, timber planks and firewood which probably had been collected from the kayas. Although a considerable amount of pole resource wais available in the kayas the observed vegetation degeneration through plant resource extraction, fire, and grazing, was likely to be at a faster rate compared to the natural regenerative ability of the forests, thus threatening the existence of these kayas forests. The immediate challenges facing kaya conservation, therefore, include re-empowering the cultural management systems, and the provision of short-term and long-term alternatives for the forest plant resources in the face of increasing demand for the resources and social change.