Human use, reproductive ecology, and life history of Garcinia gummi-gatta, a nontimber forest product, in the Western Ghats, India

The harvest and sale of Non timber forest products (NTFP) by local communities has been suggested as a possible solution to the often observed conflict between forest use and forest conservation, due to the lower impact of NTFP harvest as compared to timber harvest. Recent studies have however suggested that the economic rewards might not be constant, and that ecological effects of harvest might be higher than previously believed. In India, the trade in NTFPs has a long history but few studies have explored both the ecological and socio-economic aspects of harvest. I report here, the results of a socio-economic and ecological study on the harvest of fruits from a rain-forest tree, Garcinia gummi-gatta , which occurs in the tropical forests of the Western Ghats. I studied the characteristics of G. gummi-gatta fruit harvest, socio-economic factors that influence harvest, and the ecological effect of fruit harvest.; The genus Garcinia, which is well represented in the Asian flora, is dioecious, and some species are apomictic. I studied the occurrence of apomixy, the mode of pollination, flowering phenology, flower production, and fruit set in a G. gummi-gatta population. G. gummi-gatta is dioecious and both male and female trees flower in the dry season.; In order to understand the life history of G. gummi-gatta, I studied fruit production, seed dispersal, seed predation, seedling growth, seedling survival, spatial distribution of seedlings, juveniles, and adults, and adult tree growth. I found low interannual variability in fruit production at the population level. The degree of participation of individual trees in fruit production however varies from year to year. There is a significant positive relationship between tree size and fruit production.; Seedlings in canopy gaps showed significantly higher growth than seedlings in shade. Canopy cover however did not significantly affect seedling mortality. Larger trees whose crowns were in the canopy showed higher growth rates than smaller trees whose crowns were located below the canopy, suggesting that tree growth is influenced by light.; The analysis of population growth using a stage structured matrix model showed that the rate of G. gummi-gatta population growth was stable over the two year study period. A simulation of the effects of seed removal on population growth rate resulted in λ decreasing in small increments up to 90% seed removal, while greater than 90% seed removal resulted in a larger decrease in λ. High rates of adult tree mortality were observed in open access areas due to damage during fruit harvest.; Overall my study indicates that the ecological effects of fruit harvest are strongly influenced by the prevalent socio-economic conditions. The paradigm of ‘good extractivism’ that has fuelled much of the interest in NTFPs therefore needs to be re-evaluated in the light of increasing evidence that a complex interplay of factors, such as forest access, intra-community social dynamics, and fluctuating markets influence the ecology and use of NTFPs. (Abstract shortened by UMI.)...