Mohammed Mahabubur Rahman*
Education and Research Center for Subtropical Field Science, Faculty of Agriculture, B 200 Monobe, Kochi University, Nankoku, Kochi, 783-8502, Japan.
Md. Motiur Rahman
Silvacom Ltd., Edmonton, Canada.
Zhang Guogang
Graduate School of Agricultural Science, Ehime University, Matsuyama, 790-8566, Japan
Kazi Shakila Islam
Research fellow, The School of Oceanography and Environmental Science, Xiamen University, Xiamen, Fujian-36005, P.R. China.
Sal forest; Threats; Biodiversity; Anthropogenic impacts; Conservation; Sustainable management; Shorea robusta
Gazipur, Tangail, Mymensingh, Jamalpur, Comilla, Sylhet, Dinajpur, Thakurgaon, Rangpur, and Rajshahi districts.
Conservation and Biodiversity
Study area: The Sal forests have a fairly wide but interrupted distribution in the drier central and northern part of the mainland of Bangladesh. These forests mostly occur in the Gazipur, Tangail, Mymensingh, Jamalpur, Comilla, Sylhet, Dinajpur, Thakurgaon, Rangpur, and Rajshahi districts. The majority of the Sal forests lie in the districts of greater Mymensingh and Tangail, which is the largest belt, also known as “Modhupur Garh”. Based on geographic location, Sal forests in Bangladesh can be divided into two categories: the central plain land Sal forest and the northern plain land Sal forest. The central Sal forests are distributed in the Dhaka, Gazipur, Tangail, Mymensingh, and Jamalpur districts, including some patches in the greater Comilla and Sylhet districts of Bangladesh. About 86% of Sal forest land is situated in this central region and the remaining 14% of Sal forest belongs to northern part of the country. Sal forest lies on Plio-Pleistocene terraces in the central part of Bangladesh. The texture of the forest soil in this area is generally sandy loam to silty loam. The organic matter content in surface soil ranges from low (<1.5%) under grassland to moderate (2-5%) under forest cover. The forest soil is acidic in nature (pH =5.2 -5.5). The climatic conditions are relatively uniform over the central deciduous forest area. The mean annual rainfall increases from around 2,000 mm in the south to more than 2,300 mm in the north. The mean annual temperature is 26.30C and the average maximum and minimum temperatures are 27.50C and 18.50C, respectively. The Sal forest ecosystem supports a rich and diverse variety of flora and fauna, which includes 221 plant species and 220 animal species. Though Sal is the single most important tree species in this forest, approximately 500 undergrowth species have been reported in association with Sal trees. The special type of microclimate prevailing in the Sal forest ecosystem, with relatively higher mean annual temperature and greater rainfall particularly during the rainy season, facilitates the rich association of undergrowth diversity in this forest type. It has been reported that 24 species of climbers, 27 species of grasses, 3 species of palms, 105 species of herbs, 19 species of shrubs, and 43 species of trees have been found in the Sal forests. Similarly, animal species richness is also high in this forest. A total of 220 species of vertebrates, including 12 amphibians, 25 reptiles, 148 birds, and 35 mammal species, are found in the Sal forests . The Sal forest was well known for its peacock (Pavo cristatus), tiger (Panthera tigris), leopard (Panthera pardus), elephant (Elephas maximus), clouded leopard (Neofelis nebulosa), and sambar deer (Cervus unicolor), which have disappeared due to ecosystem deterioration and habitat loss. Moreover, the capped langur (Trachypithecus pileatus), which was abundant in this forest has been enlisted as an endangered species by the IUCN in 2008 due to habitat loss and degradation.
Tropical Conservation Science Vol. 3(1):90-102, 2010, ISSN 1940-0829
Journal