Impact of Seasons on Ground Flora under Plantation and Natural Forest in Amarkantak

Ground flora are more sensitive to changes in environment than trees Amarkantak plateau being at higher elevation has a privilege to cooler climate. Due to higher elevation, climate of Amarkantak is closely resembling with isolated valleys or islands. Amarkantak is truly unique place for this study because it has many valuable plants which are now grossly endangered in nature. The measurement of different phytosociological attributes like density, Importance Value Index, population distribution and diversity in different season have been studied in Amarkantak (Madhya Pradesh) during 1996-97 under plantations (Eucalyptus and pine) and natural sal forest. The range of number of species recorded in rainy season was highest (15-21) under Eucalyptus plantation, followed by under pine plantation and under natural sal forest, and lowest in summer (5-9) under Eucalyptus and pines plantation,. The range of IVI was highest in summer than in winter and rainy season. The population distribution was generally contiguous and random but in winter and summer the regular distribution was also involve due to severe competition for resources. Diversity index was maximum 0.245, 1.2024 and 1.3333) in rainy season and lowest (0.3950, 0.65930 and 0.946) in summer under Eucalyptus, pine plantations and natural sal forest respectively. The best adapted nich area was observed for Ophioglossum reticulatum, Ageratum conyzoides and Adiantum sp. On the basis of highest IVI in natural sal forest, Eucalyptus and pine plantations respectively. Dominance Diversity curves tended to assume the form of a series more distinctly in the winter and summer seasons, when climatic conditions are not congenial for plant growth. Thus all the vegetational changes in structure and composition are mostly dependent on seasons.