The utilization, and destruction, of forest resources have increased significantly with the progress of human civilization. Forests have been converted for other land uses (urban areas, industrial estates, sea, airports, etc) since the middle ages.
The 1st, 2nd, and 3rd industrial revolutions also accelerated these conversions, and led to the establishment of many governments and privately-owned wood-based industries in Bangladesh in the last century.
At present, large-scale wood-based industries like furniture, pulp, paper, etc, are also operating around the globe to fulfill the demand of the society. With time, people have come to realize the importance of forests for national and household demand, livelihood, and environmental wellbeing.
Assessment of forest resources is essential to ascertain the present and future uses. On the other hand, the conversion, protection, and conservation initiatives for the forests of Indo-Bangladesh have changed with time.
Knowledge of the importance of forests at the local, regional, and global scale, and utilization of forest resources help to formulate the forest policy, conservation, and utilization strategies. Therefore, the existing forest policy, demand of society and nation, available knowledge and technologies, and contemporary national and global issues ultimately govern the extent and objectives of forest inventory.
Forest inventory is the footing of forest management. Bangladesh has a long history of scientific forest management that started in 1869 with the appointment as Assistant Conservator of forest for the region. However, good numbers of forest inventories have been reported for Indo-Bangladesh since 1764. The initial inventories delineated the forest boundary, and the latter assessed the biomass and carbon stocking in a forest ecosystem, land use, and community dependency on the forest using a field survey to high-resolution satellite image.
This study reviewed all the available inventories of Indo-Bangladesh to the independent Bangladesh based on objectives, use of technologies, and outputs, and tried to align with the motive of the rulers, existing forest policy, and contemporary national and global issues.
The forests of Bangladesh can be classified into five zones as Sundarbans, Hill, Sal, Coastal, and Village. Early inventories (1764 to 1960) were vested only for the Sundarbans, but the highest number of inventories were conducted for the Hill zone, followed by the Sundarbans. A wide array of output was observed for these inventories, and were found to vary in terms of time, availability of technologies, resource utilization, quality and quantity of forest resources, forest policy, and need of the society and country.
The mid-eighteenth to the late nineteenth century saw the British colonial regime in India. The forest inventories during this period were only vested for the Sundarbans. The British East India company took absolute control over the Indo-Bangladesh after the battle of Plassey in West Bengal and Buxar in Bihar in 1757 and 1764 respectively. As new administrators, they had developed maps to demarcate the boundary of important places and areas of interest, which enabled them to ensure their strategic, administrative, and economic activities over the territory.
As part of these activities, the British administrator took the first initiative to demarcate the boundary of the Sundarbans in 1764. They also prepared a map of larger waterways of the Sundarbans from 1767 to 1773. Eventually, it was the part of The Bengal Atlas that was published in 1779 by James Rennel.
The trigonometric methods of the survey gained popularity and accuracy over the previous technology of cartography at the beginning of the nineteenth century in India. From 1821 to 1829, Lt Princep and Lt Hodges used trigonometric method of the survey to delineate the accurate boundary between the Sundarbans and cultivated lands and they produced a map for the Sundarbans.
Delineation of forest boundary and prepared forest maps were used to convert a part of the Sundarbans to cultivable lands, and a significant forest area was converted to agricultural lands within 1875. However, this conversion was not profitable due to the unfavourable environmental conditions and less productive capacity of the soil.
After 1865, a significant improvement was noted with the declaration of the Indian Forest Act 1865. Appointment of an Assistant Conservator of Forests in 1869 was the first step of Forest Administration in Indo-Bangladesh, which was the start of scientific forest management in Indo-Bangladesh. Moreover, the first forest policy was declared in 1894 with the objective of revenue generation from the forests, and giving importance to advancing the agriculture sectors.
The forest policy of 1894 likely influenced the revenue generation from the forest through production forestry, as well as continued to convert forest areas to agricultural lands. It can be believed that the objectives/outputs (such as demarcation of forest areas, preparation of forest maps, and stock assessment) of the subsequent inventories were to detect the change dynamics over time.
Dhaka, Chittagong, and the Sundarbans forest divisions were established at almost the same time. However, the Sundarbans got the attention of the forest inventory during this period. The 5th forest inventory was conducted from 1905 to 1909 to produce maps to assess the changes in forest land cover after the conversion to agricultural lands.
A comprehensive new Forest Act was adopted in 1927. The administrative capacity of the forest personnel was enhanced significantly for the management of the forests. On the other hand, the forest policy 1894 was revised in 1955 to address the contemporary issues after the independence of Pakistan, and a new forest policy was declared in 1955.
This policy was significantly updated with the view of the utilization of forest resources for the national demand as well as conservation of forests and protection of wildlife. The policy statements have influenced the outputs of the subsequent inventories from 1958 to 1984.
A total of 15 forest inventories were conducted during this period. The policies in 1955 and 1962 emphasized on the commercial utilization of forest resources as production forestry, development of forest base industries, and improvement of forest stock through natural regeneration and plantation. It is believed that these policy statements had significantly influenced the utilization and management of forest resources, and formulation of objectives of the concerned forest inventory.
Remote sensing (aerial photo) technology was used in 1958 for the first time in the forest inventory with the field survey. It was the evolution in preparation of more accurate forest maps with a larger scale.
The first forest policy approved in 1979 after the independence of Bangladesh, which continued until 1994, focused on the scientific management of forests, development and raw material support to forest-based industries, discouraging the conversion of forest areas to other uses, enhancement of plantation activities in coastal areas and depleted hills, and ensuring the mass participation in plantation.
The first inventory on village forest (village zone) was conducted in 1980-81 to estimate the wood and non-wood stocking. During 1981 to 1984, a total of four inventories was conducted for the hill zone, to assess the growing stock, delineation of forest type, and preparation of maps using field survey and aerial photos.
On the other hand, Overseas Development Administration (ODA) in 1980 conducted a comprehensive inventory for the Sundarbans. It was the first generation of modern inventory comprising seven outputs. Till today, this inventory is considered as a basis of comparison for the vegetation types of the Sundarbans and growing stock.
Piloting of coastal plantation was mentioned in Forest Policy 1962, while the Forest Policy 1979 gave further importance to the implementation of the coastal plantation in the coasts and offshore islands.
During 1987, the first inventory was conducted on the coastal afforestation with mangrove species. In this inventory, Bangladesh Space Research and Remote Sensing Organization (SPARRSO) produced land accretion and plantation maps. They also assessed the growing stock and growth of the coastal plantation.
A new forest policy evolved in 1994. This policy highlighted the mass scale afforestation on both public and private lands; conservation and protection of biodiversity and natural habitats; implementing various efforts and government ratified agreements relating to global warming; desertification; encroachment, illegal felling of trees, and hunting of wild animals; and effective utilization of forest products/ resources.
This policy opened a new horizon of forest management in Bangladesh, which reflected in all aspects of subsequent forest inventories for the different forest zones. On the other hand, National Environmental Management Action Plan was developed for the period of 1995 to 2005 to address the actions required to reduce the rate of environmental degradation, improvement of natural environment, conservation of habitats and biodiversity, which were very much related to the forestry sector.
At the beginning of the 21st century, the Sal zone of Bangladesh (Sal Forests of Dhaka, Tangail, Mymensingh, Dinajpur, Rangpur, and Rajshahi forest divisions) was bought under inventory for the first time to assess the growing stock, forest structure, list of the major species, and regeneration status. Two nationwide, comprehensive inventories were conducted in 2005-2007 and 2017 to assess the forest cover, land classes, and other parameters.
However, the nationwide forest inventory of 2017 used the latest modern equipment and data collection methods with a higher degree of accuracy compared to all inventories in the past. A special inventory on the floral diversity of the Sundarbans was also conducted in 2014. Besides these, there were four inventories in different protected areas of the Hill and Coastal zones of Bangladesh.
Climate change issues and their mitigation measures, and the role of forests have been well-discussed agendas around the globe and in Bangladesh from the beginning of this century. Along with these, multiple other action plans had significant contributions in formulating the objectives/outputs of the forest inventories in the early 21st century. It could be the reason to estimate the biomass and carbon stock in the forested and protected areas by most of the inventories in this period. These measurements and outputs of the recent forest inventories have made it compatible with the national and global interest in climate change mitigation measures.
The forest inventories in Bangladesh were started before forest management initiatives began during the Indo-Bangladesh regime. With time, the objectives and outputs of forest inventories aligned with the demand of society, administrators of the country, and forest policies.
It is evidenced that forest inventories of Bangladesh have addressed the national and global climate change perspectives, which is the prime concern at this time. It is believed that the present form and extent of forest inventories in Bangladesh will be able to support the sustainable forest management and sustainable development of the country.
Dr Mahmood Hossain is Vice-chancellor, Khulna University.