The Government of Bangladesh constructed many polders and embankments in the late 1960s to block the ingress and egress of tidal waters and facilitate irrigation for agricultural (Dev, 2013). Failure to manage locks or gates of these structures results in the gates of these enclosures often getting silted and the agricultural land inside becoming waterlogged (Rahman, 1995). As a result, thousands of acres of land in coastal areas have become permanently waterlogged. In Bangladesh, about 5% of potential agricultural land remains waterlogged during monsoon and the latest survey report shows that between 2009 and 2014, about 605,300 households were affected by waterlogging (Bangladesh Bureau of Statistics, 2016). Nearly 16,060-million-taka damage and losses were caused by waterlogging alone; of which, 50% was due to loss of crops (Bangladesh Bureau of Statistics, 2016).
The problem has been aggravated by increased precipitation due to climate change. As such, communities need to solve it. One solution is to improve maintenance of the gates but this often runs into conflict between shrimp and rice farmers. Climate change and potential sea-level rise may inundate more crop lands permanently. Prolonged waterlogging would create additional adaptation challenges such as salinisation of agricultural land in these areas and migration, and mitigating this requires urgent solutions. One such solution is known as Baira—a technique to build floating agricultural beds using water hyacinth and soil in order to cultivate agricultural crops on a wetland.
Describing the role of Baira, the Ministry of Agriculture of the Government of Bangladesh states ‘… the system generating goods and services sustainably for the locals and practitioners date back a few thousand years in southern Bangladesh. … Without the system, cultivating only Aman rice in deep water would be still prevailing in this region’ (Ministry of Agriculture, 2017). The Ministry states that the centuries-old system has undergone several environmental and socio-economic changes and includes the latest technologies to enable farmers to cultivate diverse crops. Adoption of new crop varieties and cultivation methods enables local farmers to ensure food and livelihood security by improving cropping intensity on these platforms. Initiatives from local and international NGOs have helped to scale this up as they disseminate this indigenous knowledge and technology among farmers through several training sessions. ‘… From 2011, the government also took part in dissemination collaborating with NGOs’ (Ministry of Agriculture, 2017).
The technique requires farmers to use country boats to move along the floating platforms and to prepare the bed, do the weeding and also the harvesting (Fig. 12.5). It is an older form of modern ‘hydroponics’ and requires less inputs. The technique has several names—Baira, Dhap, Gaota, Geto, Floating Cultivation (Vashoman Chash) and others (Anik & Khan, 2012; Irfanullah et al., 2008). Baira is the most popular name among all.
Studies have shown that floating agriculture practices if effectively managed could reduce adverse impacts of waterlogging and turn a temporarily inundated waterbody into a potential soil-less agricultural land. Besides Bangladesh, floating gardens of Xochimilco in Mexico and Dal Lake in India also have historical backgrounds. Originally, Baira was used for seedbeds for seedlings of rainwater varieties of rice in Bangladesh. However, with interventions from the government and from the NGOs, the practice has been expanded for cultivation of vegetables such as cucumber, okra, ginger, bitter gourd, Arum, potato, turmeric, brinjal, Lal sak, Palang sak, Danta, cauliflower, pumpkin and chilli (Anik & Khan, 2012; Chowdhury & Moore, 2017; Islam & Atkins, 2007).
The process of preparing a floating bed requires several steps. First, a stack of mature water hyacinths (a weed which has a slow rate of decomposition) is used to prepare the base of the floating bed and to create stability and buoyancy (Irfanullah et al., 2008). In the second layer, farmers use other forms of manure to speed up the rate of decomposition. Usually within 8 to 10 days, beds are ready for farmers to transplant seedlings (Dev, 2013). Typically, I-shaped (narrow) floating agricultural beds are common, and however, the size and shape of beds vary upon the volume of the ditch or waterbodies (Chowdhury & Moore, 2017; Hasan et al., 2017; Islam & Atkins, 2007). In general, the length of the beds is between 60 and 10 m and the breadth is between 1.25 and 4.0 m. The fully prepared beds are anchored using bamboo poles to safeguard against the currents and wind. The residuals of floating beds prepared during monsoon are usually utilized to prepare winter gardens to grow vegetables (Irfanullah et al., 2008). The preparation requires about two to three weeks’ time and involves only labour as water hyacinths are readily available in all wetlands in Bangladesh except in highly saline areas (Dev, 2013). Productivity is about five times higher than in traditional land-based agriculture (Dev, 2013). The production system not only builds resilience against waterlogging but also ensures greater food security, local employment and better management of water drainage systems (Dev, 2013). To improve the sustainability of the production system, farmers need training on creating the beds, selecting the crop and on maintenance of the bed during the season. These are done with support from the government and NGOs.
4.1 Case III: Intervention
In this section, we will primarily highlight a project-based case assessment documented in a journal article by Irfanullah et al. (2011). The project of promoting floating agriculture was implemented by the NGO Practical Action under the funding of UKaid. The assessment of the first project was carried out among the haor (a wetland ecosystem situated in the north-eastern part of Bangladesh) communities from 53 villages of Kishoreganj and Sunamganj districts of Bangladesh in 2007—a year which saw major flooding (Irfanullah et al., 2011). The selected households were based near relatively stagnant water and had access to water hyacinths to make floating agricultural beds. Despite being affected by monsoon floods these communities managed to cultivate the following six vegetable seeds amaranth (data shak), red-amaranth (lal shak), bottle gourd, hyacinth bean, kang kong (gima kolmi) and pumpkin in 177 floating platforms while 23 platforms were damaged in the rainy season (Irfanullah et. al., 2011). Similarly, the same communities managed to cultivate diverse vegetables in the winter season in early January 2008. About 83–90% of vegetables cultivated were consumed by the participants while the rest were sold in the marketplace or distributed among neighbours or relatives. This intervention highlights that despite being affected by floods—floating agriculture in relatively stagnant haor water was cost effective, generated employment, ensured food and nutrition and in the best-case scenario created profitability. Similar outcomes were found later in between 2010 and 2012 when Practice Action trained and promoted floating agriculture in 700 relatively poor families in the four northern districts of Bangladesh including Gaibandha. A total of 131,600 kg of vegetables, grown on about 1,500 floating beds, helped these communities to meet local food demand at the community level and generate additional income at the household level (Irfanullah, 2013).
4.2 Case III: Impact
Success in floating agriculture in the coastal and waterlogged areas in Bangladesh led Bangladesh Agriculture Research Institute (BARI) to research and develop improved strategies to produce more. It has also induced the Department of Agricultural Extension to develop strategies to promote such practices as a resilience building exercise in areas suffering from waterlogging in Bangladesh. In addition, several local, national and international NGOs are supporting projects to promote floating agriculture in Bangladesh as part of climate adaptation programmes (Chowdhury & Moore, 2017).
Though the floating agricultural production system is not particularly suitable for open water or extreme flood-prone areas, the scope of scaling up of this system in wetlands in different parts of Bangladesh is immense. As this system coincides with features of climate change adaptation, international donors, especially FAO, would be interested in providing funds for promotion of ‘Baira’ across waterlogged lands in Bangladesh.
At present, floating agricultural practice in Bangladesh has been recognized as a successful strategy for building resilience in waterlogged areas and so it is seen as a possible adaptation strategy against climate threats. In addition, it is also linked to several sustainable development goals as it fulfils the objective of reducing hunger and poverty, increasing food security and even empowering women. Many of the workers in such farms are women as it requires less physical labour. Little investment is required as country boats are used for collection of water hyacinth, carrying of produce and other inputs. It is also an environmentally friendly agricultural practice as it requires no pesticides and uses fewer chemical fertilizers. Vidanage et al., (2022, Chap. 15 of this volume) and Kattel and Nepal (2021, Chap. 11 of this volume) have also showed examples of communities-level mobilization to promote adoption of climate resilient technologies in rural areas.