Regeneration Status Of Species Research Articles

Natural regeneration status and soil seed bank composition in IITA Forest Reserve, Ibadan, Oyo State, Nigeria

The International Institute of Tropical Agriculture (IITA) Forest Reserve is a secondary rainforest that has been protected since 1965. It serves as a refuge for many species that were once common but have declined, due to urbanisation and population pressure. The study was conducted to assess the natural regeneration status and soil seed bank composition of the Forest Reserve. Two transects of 500 m were laid out using systematic line transect sampling technique. Ten sample plots of 25 m × 25 m (625 m2) on each line transect were used to identify tree species. Subplots of 5 m × 5 m for shrub and climber species, as well as 1 m × 1 m for herb species were demarcated at the corners and centre of the main plots for identification. Quadrats (15 × 15 cm) were laid out at the corners of the plots and at the centre for soil collection at depths of 0–5 cm, 5–10 cm and 10–15 cm. The regeneration status of species was determined based on sample size of seedlings, saplings and mature trees. Floristic compositions in the Forest Reserve included 58 tree, 26 shrub, 19 climber and 6 herb species. The natural regeneration status of the Forest Reserve was good with high numbers of seedlings (465/ha; 37.05%) and saplings (431/ha; 34.34%) compared with mature trees (359/ha; 28.61%). The families observed to be most abundant in the regeneration were Malvaceae, Moraceae and Apocynaceae. A total of 21 species was recorded using the seedling emergence technique. There were 11 herbs, six climbers, one shrub and three tree species. Similarity between standing vegetation and seed bank was low (0.067). The study revealed a poor soil seed bank composition, suggesting that regeneration of woody species from the persistent seed bank would be hampered if the standing vegetation is degraded.

Impact of Forest Fire Frequency on Tree Diversity and Species Regeneration in Tropical Dry Deciduous Forest of Panna Tiger Reserve, Madhya Pradesh, India

ABSTRACT The current study analyzes the tree diversity and regeneration status of species between repeated forest fires and unburned areas of the tropical dry deciduous forest of Panna Tiger Reserve (PTR), Madhya Pradesh, Central India. Fire frequency maps were prepared with the help of Landsat 5, 7, and 8 satellite images, and the study area was classified into seven fire frequency classes (B1 to B7) and one control class (B0). Five plots were laid in every fire class including the control. A total of 45 tree species belonging to 33 genera and 20 families were recorded during the study period and of these, 44, 26, and 25 species were recorded in the three-growth stages: trees, saplings, and seedlings, respectively. Of the 7873 individuals recorded, 2667, 1243, and 3963 were seedlings, saplings, and trees, respectively. Our results showed that tree species diversity was higher at moderate fire frequencies than controls, but decreased with increasing fire frequency classes. Regeneration of species was significantly different among all fire frequency classes. Certain fire-tolerant species were increasingly dominant with increasing fire frequency classes. With fires left to continue unabated, the dry deciduous forest of the Central Indian region could have lower tree diversity in the future.

Comparison of Regeneration and Yield Status between Community Forest and Collaborative Forest

The present article primarily addresses the silvicultural system (i.e., irregular shelter wood system) in Sal forest adopted in both community and collaborative forest in Kapilbastu district of Nepal. Systematic sampling with 0.5 percent sampling intensity along with statistical tools like SPSS and MS-Excel were used for resource inventory and data analysis, respectively. The result of the study shows notable increase in seedling status during the first year (2015/16) in community forest. A decrease in sapling number during the second year (2016/17) was noticed in Tilaurakot collaborative forest at its initial level of implementation. At the same time, community forest has higher yield status with a smaller number of trees felled in Tilaurakot collaborative forest under regeneration felling. The regeneration status of species varied insignificantly (p>0.05) between the community forest and Tilaurakot collaborative forest. A recommendation is made for proper implementation of irregular shelter wood system for managing the existing degraded Sal forests of the Terai region of Nepal; however, its long-term effects on plant species diversity should also be further studied in detail.

Population structure and regeneration status of rhododendrons in temperate mixed broad-leaved forests of western Arunachal Pradesh, India

ABSTRACTThis study was conducted to investigate the population structure and regeneration status of Rhododendron tree species in temperate mixed broad-leaved forests in Tawang and West Kameng districts of western Arunachal Pradesh, India. Population structure was determined through densities of seedlings, saplings and adults from the sampling quadrats. Based on density of individuals at the seedling, sapling and adult, the regeneration status of the species was determined. Density and basal area of the selected rhododendrons ranged from 16 individuals ha−1 to 1422 individuals ha−1 and 0.24 m2 ha−1 to 131.30 m2 ha−1, respectively. Rhododendron species (viz. R. arboreum, R. arboreum ssp. delavayi var. delavayi, R. barbatum and R. kesangiae) exhibited reverse J-shaped distribution with the density of sapling less than seedling and adult population. Density of selected Rhododendron species is found to be higher between the girth classes 10-30 cm to 130-150 cm and decreased with the increase of girth in all the study stands. About, 90% degrees of disturbances recorded due to cooking and space heating purposes. Among the regenerating species, 77% of the species exhibited fair regeneration, 8% species showed good regeneration while 15% of the species exhibited no regeneration. However, 90% of the tree species showed fair regeneration in disturbed stands than the undisturbed stands. Selected Rhododendron species exhibited fair regeneration in their respective stands. Inadequate regeneration status and population structure of tree species, including rhododendrons, are observed as the density of sapling less than seedling and adult population. Anthropogenic disturbances resulted to be declined in populations of Rhododendron and may lead many species to endangered, rare and threatened categories. Therefore, proper conservation and management initiatives with active involvement of local people are urgent need to protect this keystone plant species in their habitat particularly in western Arunachal Himalaya.

English

The present study deals with species diversity, and regeneration of Quercus floribunda Lindl forest lies in moist temperate sites in Nainital of Kumaun Himalaya. Tree, sapling and seedling density was 490-1190, 260-1280 and 100-670 ind.ha-1, respectively. The species diversity of trees and shrubs density ranged from 0.421 to 1.177 and 310 to 1540 ind.ha-1. The regeneration of Q. floribunda was J-shaped in forest site-1 and 2 while I-shaped (no regeneration) was reported for the forest site-3. The regeneration status of species in the studied forest sites indicates the impact of disturbances caused by anthropogenic activities. Thus, the presence of either seedlings or saplings and or also occurrence of new plant species in forest site-1 and site-2 predict the possible change in forest species composition in coming years while there was a very alarming condition in forest site-3 as new recruitments of tree species is evidenced by their absence. Thus, the above findings of Q. floribunda have shown that there is an urgent need to provide judicious inputs of management and conservation for sustaining the oak species in such forest sites of the region. Key words: Quercus floribunda, species diversity, trees, saplings, seedlings, regeneration, moist temperate.