Wild-Spikenard (H. Suaveolens) Re-Invasion Pattern in Tropical Semi-Arid Environment Due to Distance from Filed-Edge-A Pilot Study

Abstract

The study of re-invasion of Hyptis Suaveolens has been conducted in two plots of tropical semi- arid environment of India in the district of Bankura, West Bengal. The two plots were eradicated of Hyptis in 2007 and data of counts were collected in every succeeding years until 2010, when populations reach a level prior to 2007. The data collected in quadrates were finally reduced to horizontal and vertical strip totals respectively, for each years. A hypothetical factor named Unified Field Edge Factor (UFEF) has been used to account the effects of field edge and field-side anthropogenic activities on distribution pattern of Hyptis. Regression equations have been developed for estimating population at different distances from UFEF. Spatial variation has further been addressed through Fourier frequency analyses and mutual correlation analyses of horizontal and vertical strip totals of Hyptis populations in different years. It was revealed that the pattern of spatial variation remain almost regular, although the total populations of Hyptis scaled up every year after eradication until it reach a saturation value almost alike that prior to the same.