Structure and Function of High Altitude Forests of Central Himalaya II. Nutrient Dynamics

This paper deals with nutrient dynamics in horse chestnut, silverfir and kharsu oak forests in a high altitude region of CentralHimalaya. In general, the nutrient concentrations in differentlife forms were of the order: herb > seedling > shrub> sapling > tree, whereas the standing state of nutrientswere of the order: tree > herb > shrub > sapling >seedling. Of the total nutrients in the system, soil litterand vegetation, respectively accounted 66·5, 0·6and 32·9% in horse chestnut, 61·4, 0·8and 37·8% in silver fir, 58·1, 0·8 and41·1% in kharsu oak forests. Considerable reductionsin concentrations of nutrients in leaves occurred during senescence.Annual transfer of litter (above-ground+below-ground) to thesoil by vegetation of all forests ranged from 68-163 for N,4-7 for P, 26-48 for K, 62-150 for Ca and 2-4 kg ha^-1 year^-1for Na. Turnover time for different nutrients ranged between1·41 and 1·75 years for horse chestnut, 1·33and 2·13 years for silver fir, and 1·32 and 1·75years for kharsu oak forests. The distribution of nutrient contentsand net annual fluxes within the system have been developedto represent nutrient dynamics in compartment models.Copyright1995, 1999 Academic Press Standing state, turnover, retranslocation, nutrient concentration, internal cycling, uptake