Setting of the study area in the CHT region: The CHT region is a unique geographical and cultural landscape located in the southeastern part of Bangladesh. It comprises three administrative districts – Rangamati, Bandarban, and Khagrachari. Twelve different ethnic groups live in the region – the Chakma, Marma, Tripura, Mrung, Tanchangya, Bawm, Chak, Pangkhua, Lushai, Khyang, Khumi, and Rakhain (Ahammad and Stacey 2016). Aside from these traditional ethnic groups, the Bangalee (the predominant ethnic group in the country) account for almost half the population at present. Indigenous ethnic groups comprise 51% of the population (UNDP 2009). The majority of rural households in the CHT are dependent on agriculture-related activities such as swidden farming and conventional plainland agriculture, including horticulture, for producing food and generating income. Over 50% of the annual net income of all CHT households also comes from different agriculture-related activities (UNDP 2009). Forest and trees provide a wide range of benefits to local communities in the CHT, as well as to the national economy (Ahammad and Stacey 2016). Fuelwood, foods (mainly vegetables, mushrooms, bamboo shoots, animals), primary medicines, shelter-building materials, and agricultural implements are common forest and tree uses in the region. Bamboo and thatching grass are directly used for building houses (Miah et al. 2012). The level of forest dependency or its economic contribution in the CHT may be higher than in other regions due to the diversity of products and uses, as well as persistent pressure for the conversion of forest into agricultural land (Ahammad and Stacey 2016). An over-harvesting of trees, and clearing/burning in swidden farming, has caused the deforestation and degradation of the forest landscape in the CHT (Ahammad et al. 2019; Hasan, Sarmin, and Miah 2020). A limited number of local people have access to lands with a secure title for private forests or tree-covered lands that are not properly documented. As a result, sustainable forest use is a key challenge due to severe deforestation and the land-use rights of local communities that have not been properly addressed in national policies and legislation (Ahammad, Stacey, and Sunderland 2021).
Data collection approach Selection of the study sites We considered the location of the settlements, in terms of distance to market, population density, economic activities, forest types, and forest management – as proxies for three site selections (referred to as remote (Site 1), intermediate (Site 2), and on road (Site 3) locations), following Deakin, Kshatriya, and Sunderland (2016) and Sunderland et al. (2017) (see Table 1 and Figure 1). A scoping survey was organized in 2015 to select the three representative sites and villages following these criteria (Ahammad and Stacey 2016). The three sites and respective villages were selected after consultation and discussion with local government and non-governmental organization officials, and local elected union chairmen/members in the region. Twelve villages were randomly selected within the three sites that fall within the three subdistricts – Belaichari, Rowangchari, and Bandarban Sadar. The remote site was situated in Belaichari (Rangamati district), the intermediate site in Rowanchari (Bandarban district), and the on-road site in Bandarban Sadar (Bandarban district). The distance of the remote site to the main road/district town is approximately 45 kilometers (km) and 2–3 hours journey by water transport. The villages of the intermediate site are 5–8 km distant from the main road and one hour travel to access a district market. The villages in the on-road site are within close proximity (i.e., 1–3 km) to the main road and market (Ahammad and Stacey 2016).
Data analysis After data cleaning, we used the information from 289 households to analyze their uses of forest and tree products. The main statistical analyses applied were descriptive statistics and logistic regressions. The descriptive analysis provided counts of the respondents who used the household forest and tree products, such as fuelwood, timber, bamboo, wild animals, vegetables, mushrooms, bamboo shoots, fodder, thatch, and broom grass. The proportions of respondents who used specific forest and tree products for subsistence and cash income were calculated. To predict the key determinants of the households that explained variations in the forest products used, we analyzed the socioeconomic characteristics (family size, education level, farm size), sites (location of the household in Site 1 (remote), Site 2 (intermediate) and Site 3 (on-road) and ethnicity (Ethnic Group 1, Ethnic Group 2, and Ethnic Group 3). The surveyed ethnic groups comprise Tanchangya and Chakma (Ethnic Group 1), Marma (Ethnic Group 2), and Bawm and Pangkhua (Ethnic Group 3). A logistic regression model was developed to examine the key determinants (Equations (1) and (2)). The logistic regression model explained the outcome (categorical) variables using predictor (one or more categorical or continuous) variables (Equation (1)). In order to predict which forest and tree products (outcome variables) used by the households were determined by the household characteristics (predictor variables), we considered the logistic regression in Equation (2).