Dm Bhat

Biomass estimation equations for tropical deciduous and evergreen forests

In this study, linear and non-linear regression equations were developed to estimate biomass of tropical forests along with estimates of goodness of fit and percentage of errors. Basal area, average height of trees and tree density data from published reports, were used to develop equations to estimate biomass of deciduous and evergreen forests. Basal area and height of trees are found to give high goodness of fit and low percentage of errors for deciduous forests. Generally, the coefficient of determination (r²) was low for evergreen forests, probably due to the presence of trees of different height in different canopies that may have different growth rates. The coefficient of determination was high and estimate of error was low for deciduous forests. Thus, the biomass estimate equations for deciduous forests are precise and therefore useful for field applications.

Carbon stock dynamics in the tropical rain forests of the Uttara Kannada district, Western Ghats, India

Carbon stock dynamics was monitored in the Uttara Kannada district, Western Ghats, India, for ten years on eight one-hectare sampling areas belonging to different management and forest categories. The study was initiated in 1984 and the area was monitored until 1994. Our study indicates that, in general, the carbon stock has enhanced during the study period with an average growth of 1.008 t/ha/year. However, there were differences in carbon stocks in different management regimes. The minor forests that are subjected to intense human pressures had a negative growth rate, i.e. 0.237 t/ha/year, while the reserve forests have a carbon assimilation rate of 1.31 t/ha/year. This indicates that human pressure has certainly decreased the carbon accumulation in the forests of Uttara Kannada. Despite the anthropogenic pressure, the minor forests have higher carbon accumulation through recruits as compared to the reserve forests. Thus it is suggested that a management strategy is needed to look into enhancing recruitment patterns in the minor forests which would become future carbon stocks.

Implications of Impacts of Climate Change on Forest Product Flows and Forest Dependent Communities in the Western Ghats, India

Abstract The tropical wet evergreen, tropical semi evergreen and moist deciduous forest types are projected to be impacted by climate change. In the Western Ghats region, a biodiversity hotspot, evergreen forests including semi evergreen account for 30% of the forest area and according to climate change impact model projections, nearly a third of these forest types are likely to undergo vegetation type change. Similarly, tropical moist deciduous forests which account for about 28% of the forest area are likely to experience change in about 20% of the area. Thus climate change could adversely impact forest biodiversity and product flow to the forest dependent households and communities in Uttara Kannada district of the Western Ghats. This study analyses the distribution of non-timber forest product yielding tree species through a network of twelve 1-ha permanent plots established in the district. Further, the extent of dependence of communities on forests is ascertained through questionnaire surveys. On an average 21% and 28% of the tree species in evergreen and deciduous forest types, respectively are, non-timber forest product yielding tree species, indicating potential high levels of supply of products to communities. Community dependence on non-timber forest products is significant, and it contributes to Rs. 1199 and Rs. 3561/household in the evergreen and deciduous zones, respectively. Given that the bulk of the forest grids in Uttara Kannada district are projected to undergo change, bulk of the species which provide multiple forest products are projected to experience die back and even mortality. Incorporation of climate change projections and impacts in forest planning and management is necessary to enable forest ecosystems to enhance resilience.Key Words: climate change, non-timber forest products, yield, tropical forests, Western Ghats

Herb layer productivity under different light gaps in the forests of Western Ghats of Karnataka, India

A productivity estimation of tree, shrub and herb layer biomass was undertaken in Uttara Kannada, a Western Ghats district in Karnataka in differentially managed forests. In addition to biomass, light gap in these sample sites was also estimated to understand the relationship between the light interception pattern at different canopy layers and their productivity. The studies indicate that tree biomass productivity decreases and herb productivity increases with increasing light gap. However, the herb biomass productivity attains maximum height at 40–60% light gaps than in plots with no trees or 100% light gap indicating that highest herb biomass is found in forests managed for leaf manure than in grasslands. This further indicates that partial shading enhances herb layer productivity. Thus, a strategy of undertaking agroforestry in villages to enhance the total biomass productivity to meet the needs of the villages was suggested.

ASSESSMENT OF PROPAGATION TECHNIQUES FOR FOREST SPECIES OF THE WESTERN GHAT REGION OF INDIA

ABSTRACT Following the failure of plantations of exotic species to provide for the varied needs of the local people, attention has turned to re-establishing indigenous species. In this study, attempts were made to identify suitable methods for propagating 85 tree species growing in the Western Ghats region of peninsular India. Of these 85, 28 species were easily propagated with no special treatment were identified. The responses of other species to seed treatments to enhance germination, such as scarification, acid and hot water were examined. Scarification was, generally, the most successful treatment. In a trial of methods of vegetative propagation, though sprouting was observed for many species, only few of them rooted. Propagation methods have been suggested for 44 tree species, and a list of 12 species that did not perform well under any treatment tried was prepared in order to identify where more work is needed. Also 49 non-tree species (37 shrubs, 3 climbers, 4 lianas and 5 stranglers) of the Western Ghats region were examined in the same way. The germination of their seed was poor, only Jasminum malabaricum (Wt.) had over 50% germination in the control and 2 other species, Acacia concinna and Prosopis juliflora had over 75% germination under different treatments. 31 species out of the 46 tried produced roots through cuttings.