Land use induced blurring of forest-grassland transition in north-west Himalaya — A case study using Moving Split Window boundary detection technique

Abstract

Transition zone or ecotone is a unique community sandwiched between two communities/ecosystems/biomes. These ecotones in Himalaya remained unexplored for many ecological aspects like biodiversity, phyto-sociology, boundary detection and even impact of change in land use pattern (anthropogenic activity). The most accepted and widespread technique called as Moving Split Window (MSW) technique is used for detection of vegetation and environmental boundaries at four different sites in the lesser stratum of north-west Himalaya. All the four sites were at different distances from the nearest human inhabited area. Anthropogenic activities like grazing, herb collection, wood collection etc. were common at proximal sites. Such activities have led to the change in land use pattern. In this study, we have tried to work out the impact of the change in land use pattern (human interference) on the vegetation and basic environmental parameters like soil pH, electrical conductivity and moisture on forest-grassland ecotone in north-west Himalaya. Data on mountain steepness was also collected and analyzed. The dissimilarity profile using the statistical tool Squared Euclidian Distance (SED) indicated that species turnover locations increase with the increase in distance of ecotones from human settlements. The ecotones at distant locations from human villages are characterized with blunt as well as sharp peaks for vegetation data, however, conditions are reverse in case of the proximal sites. The study also reveals that as the distance between the ecotone and human settlements increases, the complex conditions like multiple vegetation boundaries prevails on the transitions. In this regard, land use induced blurring of forest-grassland transition in north-west Himalaya is summed up in the study.