The Impact of Agro-well Development on Floral Diversity in Tank Cascades in the Dry Zone of Sri Lanka

The dry zone farmers of Sri Lanka have no choice but to sustain the perennial crops in the long dry period (common to the dry zone) without a use of supplementary irrigation or groundwater resources. The emergence of Agro-well based agricultural systems has been common to the North Central dry zone since the 1980s decade. There is a common believe that the Agro-well based land development projects have drastically changed the overall land use of tank cascades in the dry zone. With this contextual impression, a number of scientists emphasized that there would be serious issues on biodiversity of the cascades. But some of them emphasized that to prove this argument further research is essential. Accordingly, this floral survey has conducted and computed the Simpsons Diversity Index to compare the diversity impact between low Agro-well density and high Agro-well density cascades in the selected mini-basins of the dry zone. The results revealed that the floral diversity impacts were not at the significant level.