Diversity and management of homestead resources: The case of Sandwip Upazila, Chittagong, Bangladesh

Homestead is an area adjoining a household, where a diversified combination of perennial and annual plant species are cultivated, often in association with livestock farming, and mostly maintained by household members for the sustenance of food supply and livelihood (Mekonen et al., 2015). Homesteads comprise several layers of vegetation, ranging from herbs and vegetables to shrubs and large trees, and typically include domestic and wild animal components (Castañeda-Navarrete, 2021). In addition, homesteads involve a traditional method of land use and are considered one of the socially accepted and sustainable local solutions that have been extensively implemented by communities with limited resources (Jegora et al., 2019). Also, the homestead forest is one of the significant components of rural economies in the tropical regions of the world (Foysal et al., 2013), and understanding species composition and diversity is one of the prerequisites to ensuring sustainable management of forest resources.

The homestead resources management and utilization approach are widespread in Asia, particularly in India, Sri Lanka, Nepal, and Bangladesh (Kumar et al., 2012; Rahman et al., 2017) through the carefully managed combination of annual and perennial farm crops and livestock within the courtyard of the households. The homesteads meet several social, cultural, and ecological demands, while plant species composition of homesteads varies depending on the meteorological and edaphic conditions of the location and the household’s income (Vibhuti et al., 2018). Homestead forests are significant sources of timber, fruits, fodder, fuelwood, and medicinal tree species in South-Asian countries such as Bangladesh (Baul et al., 2021), they help household members to maintain a balanced diet with additional food, fuel, and fodder (Mekonen et al., 2015).

Furthermore, over two-thirds of the total land of Bangladesh is suitable for agricultural activities and homestead areas account for more than three-quarters of all agroforestry activities (Zaman et al., 2010). Around 20 million homestead forests cover 0.27 million hectares amounting to 2% of the total land area and 10% of the natural forest area of the country (Baul et al., 2021; Kabir & Webb, 2008; Rahman et al., 2017). The diverse species of homesteads in Bangladesh fulfill approximately 70% of timber, 70% of fruit, 40% of vegetables, 90% of fuel, 48% of sawn and veneer logs, and over 90% of bamboo requirements of the country (Rahman et al., 2017; Roy et al., 2013). However, as a result of population pressure and the conversion of land for other uses, these homesteads are being overexploited and degraded, resulting in fragmentation (Baul et al., 2021). Additionally, Kabir et al. (2016) mentioned that the species composition and diversity of homestead plants in Bangladesh depend on household land area and economic conditions, the household head’s expertise, and time spent in management. Studying homestead plant species composition and diversity is necessary to align homestead management with these factors. Besides, improved systematic management of homesteads is needed to prevent exploitation and fragmentation (Baul et al., 2021), thus the homestead resources can be maintained for the betterment of health and economic benefits of the rural communities in Bangladesh.

Sandwip is Chittagong’s sole offshore island, which is frequently hit by tropical cyclones and storm surges of varied strengths, as well as abnormally high tides, and saltwater intrusion (Paul & Rahman, 2006). Households are shrinking in size and shape as a result of land erosion caused by rivers, population expansion, and industrialization. Thus, it is vital to understand the present status of homestead resource diversity and management practices of Sandwip. Here, each household’s primary livestock component was poultry, followed by goats, cattle, buffalo, and sheep (Alam & Masum, 2005). In addition, because of transportation difficulties with the mainland, people of the offshore island heavily depend on their homestead products. Although several studies were conducted in Bangladesh on homestead forests (Alam & Sarker, 2011; Alam et al., 1996; Das, 1990; Zaman et al., 2010), traditional uses of homestead agroforest (Alam et al., 1990; Millat-e-Mustafa, 1997b; Momin et al., 1990), and natural forest biodiversity (Chowdhury et al., 2018; Chowdhury et al., 2019; Alam et al., 2019; Rahman et al., 2020; Rahman et al., 2019), no study has been done on homestead forest resource management yet on Sandwip Upazila (sub-district) of Chittagong district, while there is a considerable possibility for developing homestead resources management approaches for conserving biodiversity and ensuring food and livelihood security. Following the background, this study was conducted to understand the diversity of homestead trees or vegetation species. This study also tried to assess the various aspects of the raising and management of different kinds of species in the rural homestead forest or area of the offshore island of Bangladesh. Here, the general objective is to understand the status and diversity of homestead resources along with practice and associated problems in homestead forest management in Sandwip Upazila, Chittagong. In addition, specific objectives are to understand the diversity and distribution of the tree species of the homestead area, including species composition, homestead agroforestry pattern, and problems associated with homestead resources management.

Homestead depicts the combination of different groups or species of trees, shrubs, including vegetables within the periphery of an individual house, which is fully managed by the family members (Fernandes & Nair, 1986). Homestead is one of the most important production areas of different resources in Bangladesh, which provides a significant contribution to the group of people with low economic status (Miah & Hussain, 2010). Following the aspects of the importance of homestead resources, this study covered the diversity and management of homestead resources in Sandwip Upazila, Chittagong, Bangladesh. The findings revealed that the number of plant species (excluding vegetable species) in this study area was 57 under 28 families, which indicates the homestead has a moderately high diversity and species richness, which is higher than the findings of Abedin & Quddus (1990). They were found in homesteads of Tangail district (52 spp.), Ishurdi (34 spp.), Jessore (28 spp.), Patuakhali (20 spp.), Rajshahi (28 spp.), and Rangpur (21 spp.), respectively. Besides, in a study conducted in different regions of the country, Millat-e-Mustafa (1997a) found 92 species of perennial plants.

Furthermore, in the case of diversity and density of fruit and timber species, the Shannon-Wiener Diversity Index is higher than the Index of Dominance, indicating less dominance of the tree species with greater diversity in the home garden. The computed value of the Species Richness Index also specifies a greater diversity of tree species and a more even distribution of the total number of individual trees across all tree species. This result is consistent with those of a few studies with similar objectives. This index was reported to be 3.33 by Millat-e-Mustafa (1997a) and 3.16 by Nath et al. (2015) for homesteads of varying sizes in Bangladesh. On the contrary, it was found that the tree species in this study (Evenness Index = 1.89) were more evenly distributed than the distribution. Nath et al. (2015) found homestead forests in ecologically critical areas in Bangladesh (Evenness Index = 0.84). Shannon-Wiener’s Diversity Index values range between 1.5 and 3.5 in the majority of ecological studies, and rarely exceed 4.0. The Shannon Index rises when both the diversity and uniformity of a plant community increase. Besides, a total of 17 vegetable species were found to grow on a homestead several times a year of which 3 grew round the year. The number was higher than in another study (14 spp.) conducted by Momen et al. (2006) in Sandwip Upazila.

Moreover, eleven vegetables were found under the direct shade of trees or as a creeper in association with trees. Under the trees, various shade-tolerant and/ or shade-requiring plants, such as ginger (Zingiber officinale), turmeric (Curcuma longa L.), aroids (Colocasia indica), etc. were identified growing in homesteads. Few large and medium-sized farms were growing vegetables using horticultural and forest species, which is an additional source of income for those farms. Typically, farmers did not cultivate crops beneath the canopy of trees, although some of the mentioned species required shade. Lack of adequate knowledge, provision of inputs, and technology were identified as the primary reasons for its non-practice. In addition, the insufficiency of labor to plant and care for the vegetables was also a factor for those who do not cultivate them. Similar to the findings of Zaman et al. (2010) the present study discovered that some shade-loving plants thrive beneath and close to tree canopies. Among them, Zingiber officinale, Curcuma longa, Ananas comosus (L.) Merr., Colocasia indica, Capsicum frutescens L., Amorphophallus Blume ex Decne, and Dioscorea L. were found in homestead forests.

Furthermore, among all species, fruit species comprised the highest percentage (42%). Here, supari (Areca catechu), narikel (Cocos nucifera), and am (Mangifera indica) were the most frequent fruit tree species as these trees provided economic return and fulfilled a portion of the nutritional requirement. In timber and fuel wood species, raintree (Albizia saman), mahogani (Swietenia mahagoni), and mandar (Erythrina indica L.) have the highest frequencies. On the other hand, the present study revealed that traditional fruits of low economic value, such as chalta (Dillenia indica L.), kodbel (Feronia limonia L. Swingle), and golabjam (Eugenia jambos L.) are gradually decreasing from the homestead. Exotic timber species, such as Swietenia mahagoni, and Acacia auriculiformis are increasing in terms of relative density and frequency in the homestead. On the other hand, Ahmed & Islam (1994) indicated that about 31 minor fruit species have reached a stage of near extinction from their home in Bangladesh. Malta (Citrus limetta Risso) and apple (Malus domestica Borkh.) species were found in small amounts in very few homesteads which were provided by the government under the “Ekti Bari Ekti Khamar (One House One Farm)” project.

Farmers derive benefits from homesteads in various ways as they use homestead resources as a “reserve bank” for food and income. It was discovered that the annual average income of the small households was 13457 BDT and the large households’ annual average income was 24700 BDT. The maximum income of the households comes from selling timber. The income from trees for the small farm categories was substantially lower than the income from trees for the other farm categories. Smaller farms had fewer trees and less land devoted to tree production, which contributed to a lower income from tree products. This observation conforms with Zaman et al. (2010) homesteads study. The second highest income of different farm categories came from selling fish.

Most households (82.2%) preferred largely food or fruit species for planting due to monetary incentives and family demands, and this conclusion is supported by the findings of Masum et al. (2008) and Siddiqui & Khan (1999) and in various parts of the country. Fruit trees were preferred by farmers due to their numerous applications and consumption. According to Bashar (1999), farmers prefer fruit trees in their homesteads. The study revealed that geographical location, better financial condition, availability of planting materials, commercial values, and more so the local tradition are identified as the factors affecting people’s species preference in a different region. These findings are corroborated by the research of Millat-e-Mustafa (1997a) on home gardens in four regions of Bangladesh.

The respondents were found to use cow dung, household residue, and chemical fertilizer on their land to maintain soil fertility. In tree planting and management work male participation was (52.08%) slightly higher than that of females, however, females actively took part in the development and care of home gardens. As the area of homesteads was near female working areas it was easy for them to look after it compared to men. The site selection decision for planting purposes was mostly taken by female (34%) members and less by male members (27%). Women play the most active role in maintaining homesteads. Although men performed heavier tasks at home gardens, such as planting, thinning, and fertilization in homestead management, women and children performed lighter work, such as weeding and watering.

The majority of the respondents (60%) had given an emphasized economic value. Here, 23.33% of the respondents mentioned combined economic and ecological value and only 16.67% of the respondents were aware of the economic, ecological, and medicinal value of what home garden should be conserved. As a strategy for maintaining ecological balance and a source of medicinal plants, the majority of the respondents assessed the home garden as “least significant“. Consequently, it appears that there is still a shortage of understanding in these two areas since Roy et al. (2013) obtained similar findings.

Due to the lack of better management techniques and high-quality varieties, the traditional maintenance system of homestead gardens in the study area was characterized by a low level of cultural practices. Typically, farmers rely on plants that grow naturally inside their homestead’s perimeter. In addition, a review of the present management regime revealed that cultivators lack scientific knowledge. The vast majority of household owners still adhere to traditional homestead management approaches, while just a few have adopted modern practices. Agriculturalists, ecologists, biologists, and economists must communicate and interact across disciplines to protect homestead resources, identify and implement appropriate evaluation methodologies for sustainable management, and increase profits from the homestead. A greater understanding of agro-biodiversity as natural capital for delivering ecosystem goods and services is required. This knowledge will assist in increasing agricultural output and encouraging forestry (Swift et al., 2004; Wood & Lenné, 2005) in the least forested regions by building human-managed farm forestry.

In terms of plant management and utilization, Bangladesh homestead forestry practices are following conventional methods and need improvement. Findings reveal that homesteads provide tangible benefits, such as fruit, fuel wood, and food materials with some income. There was enough unused land in the homesteads, which were relatively safe from flood and other threats. The land can be used for tree-growing purposes with desirable species. Producing various nutritious foods around the house may be a sensible way to provide adequate food to the household members. Thus, selective plantation of fruit species around the home garden can greatly influence the promotion of proper nutrition. It is evident from the study that farmers possess extensive indigenous knowledge related to several aspects of homestead forestry management. Farmers are mostly concerned about improving the growth of fruit trees in their home gardens. There is still immense scope to improve technologies for species selection, clonal propagation, species interaction, soil management, etc. To achieve a stable ecological balance and sustainable productivity of the homesteads, the proper initiative should be reintroduced along with the rare indigenous fruit trees and careful management of homesteads.

The following recommendations may be made to improve the status of homestead biodiversity: