Annual nutrients budget for the grazed and ungrazed sites of an alpine expanse in North-West Himalaya, India

Abstract

This work was undertaken to analyze nutrient contents of vegetation in an alpine meadow-Tungnath, North-West Himalaya, India. The study pertains to the uptake, transfer and release of four main macronutrients (organic carbon, total nitrogen, total potassium and total phosphorus) in grazed (exposed to extensive grazing by cattles) and ungrazed (grazing completely prohibited) communities. Mineral concentration was recorded higher for the ungrazed sites compared to the grazed sites, and maximum standing state of nutrients was found in roots. Belowground compartment (roots) contributed maximum share of mineral elements to soil. Litter nutrients release was low because of low microbial activity and continuous removal of phytomass. Observations reveal that there was very little amount of nutrient release from phytomass and vegetation in alpine are very poor source of mineral recycling. Low transfer rate of minerals from one compartment to other is adequate for greater amount of these minerals that are translocated back into the storage organs. A small proportion get removed through rain splash or through the removal of hay during grazing as relatively high release rates in ungrazed sites when compared to grazed sites was observed. This translocation can be considered as an important adaptation in alpine plants for survival during adverse environmental conditions, against all types of biotic pressures and also for regeneration in the forthcoming growing season.

Litter Production, Decomposition, and Nutrient Release in Subalpine Forest Communities of the Northwest Himalaya

“…In general, abiotic factors (like precipitation, temperature), composition of microbial and plant species, and altered chemical composition of stand types were major determinant for the release of nutrients during the course of decomposition [7,8,10,45]. Nevertheless, comparatively a small amount of the nutrients present in original above ground litter was transferred to the soil through disappearance and decomposition of aboveground litter as also reported by Rawat et al [7] and Rawat et al [8] for alpine ecosystem of Northwestern Himalaya. Litter shed by subalpine forests does not decompose completely in the subsequent favourable season and layers of litter are deposited on the floor of the forests which are subsequently replaced from the system through runoff during rainy season.…”

“…The organic matter on the forest floor is a major source of energy for heterotrophic organisms and mineral nutrients for plant growth and significantly affects hydrology and ecosystem structure and function [5]. As decomposition of plant litter is central to many ecosystem functions such 2 Journal of Ecosystems as soil formation and nutrient cycling [6,7], a thorough understanding of this process is essential in understanding the functioning of terrestrial ecosystems.…”

Characteristics of life-form and growth-form of plant species in an alpine ecosystem of North-West Himalaya

“…Similarly, an adjoining area outside (area open for grazing) the alpine field station was marked as grazed site that is grazed by large herds of cattle of local inhabitants from down-valley and gujjars (nomadic people) every year (Rawat et al 2010). The study was carried out from May to October during the growth period of plants in 2007 for intensive plant collection and observation.…”