PLANT AND SOIL DIVERSITIES IN A SUB TROPICAL FOREST OF TlIE GARHWAL HIMALAYA

摘要

The forest plays a significant role in influencing the structure of the soil by milling organic niatti-r and also affects its basic status and nutrient level. The ahilitv of the soil to retain iind the percolation of water depend upon the percent amount of sand, silt and clav. Biotic disturbances generally have ctmsctl substantial reduction in forest cover. It has been observed tliat among the aspects the regeneration status of species was poor. A number of studies relating to regeneration of eitherspecific species or the forest stand as a whole have focused on the impact oj anthropogenic factors and natural disturbances. In general, human interference and other causative factors such as grazing, browsing, trampling are severelv affecting the regeneration of this region. The study sites were dominated by Anogeissus latifolia. which is the most important fodder, fuel wood and limber tree for load people. Therefore, the heavy pressure of villagers by lopping oj leaves, cutting new saplings and treebrandies especially for firewood, are leading to poor regeneration. Among the aspects the average range of values oj soil pll (6 .13 la 6.47), soil organic carbon (0.47 to 0.68%), phosphorus (9.67 to 10.67 Kg ha~(-1)) ami potassium (141. 87 in 172.48 Kgha~(-1)) were recorded. The total highest density of tree layer (380 trees ha~(-1) i was oli.sencd on south aspect, whereas the lowest (260 trees ha~(-1)) was recorded on west aspect. In shrub layer, the total highest density (1790 shrubs ha~(-1)) was recorded on east aspect and the lowest (970 shrubs ha~(-1) on nvsi aspect. The range of values of total density and total basal cover of saplings were 200 to 550 saplings ha~(-1) and 0.78 to 1.43 m~2 ha~(-1) respectively. Similarly for seedlings layer, these values ranged from 80 to 430 seedlings ha~(-1) and 0.01 to 0.034 m~2 ha~(-1) respectively. The values oj similarity among the aspects ami different layers ranged from 25.0 to 66.67%, 22.22 to 57.14%, 28.57 to 57.14% and 57.14 % to 72. 72% for trees, saplings, seedlings and shrubs respectively. The range of diversity was O.K46 to 1.7111 (trees), 1.943 to 2.847 (shrubs), 1.10 to 1.520 (saplings) and 0.496 to 1.435 (seedlings).