IMPACTS OF CARDAMOM CULTIVATION ON FLORAL DIVERS

Abstract

Knuckles Forest Range is a unique ecosystem and extending to 160 km2 in Matale andKandy Districts of Central Province. Together with the landscape and the climate it has·resulted a variety of natural vegetation types. Among these, sub montane forests arebighly affected by commercial planting of cardamom by villagers and also by large scalecompanies,

This research was conducted in Riverston area of Knuckles Forest Range. Selectivesampling was done in the natural forest and in the areas where the undergrowth isdominated with cardamom. Within the areas, three 20 x 20 m plots were established andfollowing measurements were done; no. of species/area, no. of individuals/area and perspecies, vertical stratification in the two types of areas. DBH was measured in trees withmore than Im height.

The results depict 48 plant species in natural forest and 31 species in cardamom plantedareas, with a high number of genera and families in natural forest. 29 species out of 48species were only confined to the natural forest areas. Height and diameter distributionpatterns were different in two conditions. Species diversity (Shannon's diversity index)was significantly different and it was 1.1300 in natural forest areas and 0.5678 incardamom plantation. Density of trees (number of stems per ha) also showed suchpattern and the values were 6433 and 537 respectively. Dominance of species accordingto the Importance Value Index (IVI) in the two conditions was also different. Comparisonof endemicity in two conditions showed 45.83% in natural forest and 29.03% incardamom plantation.

The results of the present study also provide evidence as to the detrimental effects ofcardamom planting on the ecology of the sub montane forests of Knuckles Range.