No abstract

The epiphytes present at about breast height on trunks of different size were studied for three major tree species in a seasonally wet forest at 2050 m altitude in the Kumaun Himalaya: Cedrus deodora, Quercus floribunda and Q. leucotrichophora. The total biomass and species number per unit trunk area, were found to increase with trunk size. It was supposed that the results indicated a succession in the type of epiphytic cover from young trunks to older trunks.The amount of loose material (plant remains and 'soil') per unit area of trunk increased with increasing girth. The C:N ratio in this material was initially very high on the oaks and declined with increasing trunk size (to 73-78); the ratio was constant across girth classes in the cedar (86-87).Bryophytes produced most biomass on most trunks; next to them were lichens on the smallest trunks, and flowering plants on the largest. The number of species of epiphytes was similar on all three host species. The results are discussed in relation to contemporary ideas on diversity and 'strategies'.

In the most productive macrophytes stand lying within the littoral zone of Lake Naini Tal (a Kumaun Himalayan Lake, located 1937 m above sea level) the macrophytic biomass was removed a t the time of peak biomass one year, but not during the next. The effect of non-removal of the macrophytes was apparent in the physical and chemical parameters of the water, viz: thermal stratification, pH, dissolved oxygen, calcium and nitrogen content. The removal of macrophytes increased the plant diversity. Seasonal patterns of ash, calcium and nitrogen content in plant tissues mere different for the two years of study.