Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Tree-species Diversity of a Remnant Natural Dipterocarp Forest Versus Mono-plantation in Rajghat, Cox’s Bazar (north Forest Division) of Bangladesh

M. A. Mamun
Institute of Forestry and Environmental Sciences, University of Chittagong, Chittagong 4331, Bangladesh.

M. K. Hossain
Institute of Forestry and Environmental Sciences, University of Chittagong, Chittagong 4331, Bangladesh.

Abstract/ Executive Summary:

The study was carried out to assess the floristic composition, distribution, quantitative structure and natural regeneration of native tree species of Rajghat Forest Beat, Fulchari Range in Cox’s Bazar (North) Forest Division, Bangladesh. A total of 50 sample plots of 50 m x 50 m in size were taken from the natural forest and 100 sample plots of 5 m x 5 m in size were taken for regeneration study. A total of 907 individual stems of 13 native tree species were recorded from 12.5 ha sampled area, where Dipterocarpus costatus was dominant (n = 743) followed by Swintonia floribunda (n = 71). Total basal area for all trees with ?10 cm dbh was 1,047.50 m² and average basal area was 83.95 m2 ha-1. D. costatus showed highest Importance Value Index (201.48) followed by S. floribunda (37.86). D. costatus showed highest cylindrical volume (629.47 m3 ha^-1) followed by S. floribunda (57.04 m3 ha-¹). Plantation plots of FRMP (Forest Resources Management Project), woodlot, participatory and enrichment plantation comprised 42, 30, and 40 ha, respectively, where Acacia auriculiformis was highest (789 stems ha^-1). A total of 26 regenerating tree species were recorded from the natural forest. In the hill top, tree species regeneration was 11,387 seedlings ha-1, where D. costatus represents highest (4,080 ha^-1) followed by S. floribunda (1,733 ha^-1). Recruitment is not successful, because of removal of seedlings and saplings by the local wood collectors and ground fire. This natural forest is a harbour of valuable native tree species (D. costatus, S. floribunda, A. scapula, C. indica, M. sylvatica, etc.), especially for their ecological, economic, and aesthetic values. This remnant forest needs to be conserved through proper management and protection of the native tree species, especially through protection of natural regeneration.

Keywords: Tree biodiversity, Forest, Plantation, Cox’s Bazar

Location: Cox’s Bazar (North) Forest Division, Bangladesh

Start Date:

End Date:

Program Area: Conservation and Biodiversity

Commodity: Plant

Objectives:

For biodiversity conservation and successful establishment of natural regeneration, an economically- and ecologically-sound management plan is desirable. Thus, this study was undertaken to assess its tree species composition, stand structure, natural regeneration, and qualitative and quantitative distribution of plant species, which may be useful in providing guidelines for sustainable management and conservation of this remnant natural forest.

Methodology:

Selection of the study area The study was conducted in the Rajghat Forest Beat, Fulchari Range of Cox’s Bazar Forest Division (North). The Rajghat Beat has a total forest area of 566.84 ha, of which only 227.89 ha comprises natural forest. The forest area of Rajghat Beat has a cover of mature trees and a substantial portion of the forest is gradually degrading. Besides this, the Forest Department has converted the degraded areas to mono-culture by planting shortrotation exotic species, like Acacia auriculiformis, Acacia mangium etc. Sampling design for measurement of composition and structure of tree species The study area was divided into five blocks, e.g., Bital, Keyamontola, Napitkhali, Rohittarsia, and Purnogram area. From each block 10 (ten) sample plots were taken by using systematic sampling method and a total of 50 sample plots of 50 m x 50 m in size were taken. From the short-rotation plantations, a total of 15 sample plots of 20 m x 20 m in size were taken (5 plots from each type). All the plots were well demarcated, their corners were marked with pegs and then all the plants, including seedlings, saplings, and trees of all species in each plot were identified and recorded. Sampling design for regeneration study For regeneration survey, one sample plot (5 m x 5 m) was laid out at the middle of each main sample plot (50 m x 50 m) in two different slopes (hill top and hill bottom). In each block same number of sample plots was taken for the tree species. Seedlings were identified, counted, and recorded on the data recording sheet. In case of plantations, 2 sample plots of 5 m x 5 m in size were taken for regeneration assessment. A total of 30 regeneration plots in the three different-aged plantation plots were surveyed. For assessing the effect of aspects of natural regeneration, a total of 20 regeneration plots 5 m x 5 m in size were surveyed (5 plots from each aspect), which were selected randomly from the natural forest area. The Density, Relative Density (RD %), Frequency, Relative Frequency (RF %), Abundance, Relative Abundance (RA %), Relative Dominance (RDo %), and Importance Value Index (IVI) of each species were calculated according to Curtis (1959), Whittaker (1975), Shukla & Chandel (1988), Moore & Chapman (1986), and Dallmeire et al. (1992).

Source of Information: Proceedings of the International Conference on Biodiversity – Present State, Problems and Prospects of its Conservation January 8-10, 2011 University of Chittgaong, Chittagong 4331, Bangladesh

Article Link (Online Journal):

Funding Source:

Budget:

Total Budget (Tk.) :

Achievement/Findings:

At present only 13 naturally-growing tree species are available in this forest, indicating that this remnant forest is not rich in plant diversity, but it contains some threatened tree species e.g., Swintonia floribunda, Mangifera sylvatica, and so forth. Though the natural regeneration is rich, the most alarming situation is that there is a continuous removal of young saplings from the forest. Saplings are used for fencing purposes in the farmer’s crop field. Incendiary fire is occasionally caused by the local people for protecting their crop fields from wild animals (elephants, rodents, and so forth). This has encouraged the growth of grasses and weeds, which hamper seed germination and seedling growth. Cattle and goats graze in the areas, which causes damage to the seedlings and causes soil erosion. In order to maintain the complexity of this forest and its tree coverage, an economically feasible and ecologically-sound management plan is desirable with minimum disturbance to the ecosystem, but tandem use of community-based natural-resources management can help to promote appropriate use of forest resources with social, economic, and environmental benefits. A regular diameter and height distribution should be maintained through protecting natural regeneration and by developing plantation programmes for native tree species in the forest area. It can also be concluded that this investigation paves the way for further study to investigate particular reasons for variation in ground flora and regeneration in the Natural Forest of Rajghat Beat. Participatory forestry can play a vital role in protection of the natural forest, but monoculture plantation of A. auriculiformis is not an appropriate method for the conservation of biological diversity. A. auriculiformis spread in the plantation area, as well as in the adjacent natural forest, through seed dispersal and its higher survival percentage, growth rate, and capability of growing on the degraded land. Mixed-species plantation may be able to contribute to sustainable management, because monoculture plantations cannot provide the full range of goods and services of the natural forest. Mixed plantation can be appearing to extend the range of benefits from plantations, both for ecological and economic purposes. Thus, mixed plantations may contribute to the conservation of biological diversity at the level of the conservation of indigenous species in their original habitat.

Knowledge Management: Report/Proceedings