Global experts on climate change affirm that Bangladesh, due to its geographical exposure as a deltaic region, will be subject to serious climactic vulnerabilities during the 21st century. The inexorable developments in climate change could become a major threat to the country’s aspirations to ensure food security, sustainable development and poverty eradication. Agriculture is by far the most climate-sensitive sector. Hence, it is imperative that our agriculture sector adapts to the impacts of climate change and improve the resilience of food production systems in order to feed a growing population.
Agriculture is most vulnerable to climate change as its productivity totally depends on climactic factors like temperature, rainfall, light intensity, radiation and sunshine duration, which are predictably erratic. Global climate has been changing due to natural forces as well as anthropogenic activities, especially emissions of greenhouse gases and aerosols, and land use changes in recent decades. Though agriculture currently accounts for about 15% of the country’s gross domestic product (GDP), and employs around 45% of its labour force, the entire population of Bangladesh depends on this sector – which includes forestry, livestock, and fisheries – for food and nutrition.
The agriculture sector is a critical route to reach different goals stated in the Poverty Reduction Strategy under the Seventh Five Year Plan 2016-2020 as it directly reaches the poorest in the rural areas, providing both food and livelihood. The sector is already under pressure from increasing food demand, and problems associated with agricultural land and water resource depletion. The issues of climate change make the pressure more acute for the sector.
IMPACTS OF CLIMATE CHANGE ON AGRICULTURE: Global and regional weather conditions are expected to become more extreme compared to present conditions with expected increase in the frequency and severity of extreme events such as cyclones, floods, hailstorms, and droughts. By bringing greater fluctuations in crop yields and local food supplies and higher risks of landslides and erosion damage, they can adversely affect the stability of food supplies and thus food security.
One major threat for the country that has recently emerged is the predicted climate change and sea-level rise due to global warming. The growing evidence on climate change suggests that Green House Gas (GHG) emissions, resulting from the cumulative action of developed and emerging economies, would have serious deleterious effects in near future, unless effectively contained. Bangladesh will feel the impacts and must be prepared to address emerging challenges from climate change.
Figure illustrates the range of impacts expected at different levels of global warming (1-5°C). In the moderate scenario posited by the Inter-Governmental Panel for Climate Change (IPCC), global temperatures are expected to rise by 2°C by 2050 and another 3-4°C by the end of this century. Even under the moderate scenario, the Bangladesh Delta, and particularly its agriculture, faces severe challenges of falling crop yields, loss of agricultural land, decreasing quality of aquifer, loss of biodiversity, and extreme weather events, the combined effects of which could seriously threaten livelihoods of people-dependent on agriculture and related occupations.
Degradation of productive land including quality and physical loss are key concern, for coastal agriculture due to salinity intrusion and sea-level rise. Recent assessment suggested that about 13% more area (469,000 ha) will be inundated in monsoon due to 62 cm sea-level rise in addition to the existing inundated area. The most vulnerable areas are the areas without polders like Patuakhali, Pirojpur, Barisal, Jhalakati, Bagerhat and Narail. This will have a direct affect on rice and crop production, the staple food of the country and if the current situation prevails damage of agricultural crops will be more in future.
FISHERIES SECTOR: It constitutes a share of 4.4 per cent of gross domestic product (GDP) or 30% of agricultural output, and climate change can affect the productivity or distribution of fishery resources of both marine and inland waters in a variety of ways. Changes in water temperature and precipitation affect the dynamics of ocean currents, the flow of rivers and the area covered by wetlands. This will have effects on ecosystem structure and function and on the distribution and production of fish stocks.
Complex links between climate change, fisheries and other sectors will have indirect effects including fisheries being affected by changing water demands from agriculture, changing prices of and access to aquaculture feedstuffs and diversion of government and international financial resources away from fisheries management and into emergency relief after extreme weather events. Due to change in precipitation, more droughts or floods, and less predictable wet/dry seasons, there will be reduced opportunities for farming, fishing and aquaculture as part of rural livelihood systems, damage to productive assets (fish ponds, rice fields, etc.) and homes; and reduced ability to plan seasonal livelihood activities.
LIVESTOCK SECTOR: As compared to other sectors, there are very few economic analyses done on the climatic effects on livestock sector worldwide. Livestock in developed countries appear less susceptible to climate changes because they live in protected environments (sheds, barns etc.) and have supplemental feed (e.g., hay and corn). In Bangladesh, on the other hand, the mass of livestock have no protective structures.
The IPCC has reported that climate change and its impacts can result in the outbreak of new diseases and pests that will affect the livestock sub-sector. Increased flooding poses significant risks to animal mortality especially in low lying areas and reduces the productivity of poultry and extreme hot weather and creates stress in livestock and poultry which leads to less meat, milk and egg production.
CLIMATE CHANGE ADAPTATION-MITIGATION STRATEGIES: The people of Bangladesh have adapted over generations to the risk of floods, droughts and cyclones. However, impacts of climate change means the present approaches and traditional methods of adapting to climatic changes need to be reassessed and innovative measures adapted.Each individual country has to be committed to playing its part in responding to the challenge. Bangladesh may take the following mitigation measures:
DEVELOPMENT OF CLIMATE RESILIENT CROPPING SYSTEMS: For the long-term, climate change will require farmers to modify their current cropping systems or change to alternative more climate resilient cropping systems. This could mean that different regions of the country will have to develop climate resilient cropping patterns suited to its regional topography and climactic variations. Agricultural extension programmes could facilitate field trials of climate resilient cropping patterns and associated water management systems, in addition to developing seed supply and training mechanisms.
RESTORATION OF DEGRADED LANDS: Restoration of degraded lands has the potential to sequester carbon by 3.45 tCO2/ha per year. This can be achieved using practices that reclaim productivity such as revegetation (that is, planting grasses), improving fertility through nutrient management, use of organic substrates such as manures, biosolids and composts, tillage management, and retaining crop residues and water management.
MORE INTENSIVE AGRICULTURE WITH OFF-FARM ACTIVITIES: The households which mainly depend on agriculture may intensify their agriculture. They may use their land more efficiently with saline tolerant crop variety. Many of these households have started off-farm activities for additional income. So the emphasis could turn to a combination of farm and non-farm activities that support each other and ensure livelihood security.
ADAPTATION-MITIGATION MEASURES IN THE FISHERIES SECTOR: Climate change is likely to adversely affect freshwater and marine fisheries, as water temperatures in ponds and inland fisheries are likely to increase; saline water is likely to extend further inland in the south of the country, while turbulent and rough weather along the coast may prevail for longer durations adversely impacting on the livelihoods of fishermen. Adaptive measures will have to be taken in (a) fish spawning and growth of fish in freshwater fisheries, (b) fish spawning and growth of fish in the coastal zone and brackish water, (c) marine fisheries, and (d) shrimp cultivation.
LIVESTOCK MANAGEMENT AND MANURE MANAGEMENT: Livestock management through improved feeding practices can reduce CH4 emissions from enteric fermentation by 1.0-22% for dairy cattle, 1.0-14% for beef cattle, 4.0-10% for dairy buffalo, and 2.0-5.0% for non-dairy buffalo. This can be achieved by providing animals with an enriched diet that would lower the enteric methane emissions per output or input unit. Farmers can implement this measure by managing their grain supplementation, using forage from plants containing some natural methanogenic depressors, and using mineral supplements to overcome any possible nutrient deficiencies.
To conclude, policies that support low-cost technologies for improving production may prompt households to intensify their agriculture option making agricultural technologies more readily available to farmers to ensure adequate food supply and create opportunities for income and employment. Policies have to be devised for better management of fresh water and saline water flow as well as exploring options to preserve enough fresh water for irrigation. Other measures that can be undertaken are development of low cost weather controlled housing for livestock and strengthening animal disease surveillance facilities.
It is about time we consider the impact of climate change on agriculture sector on a serious note because this will be the first area on which the effect will fall upon directly. Agriculture is the backbone of our country and so many lives depend on this crucial segment for economic development. Comprehensive and coordinated study on the real time impacts of climate change on crop production and livestock management and assessment of the needs to avert the crisis must be carried out for making correct policy decision.
The irony is that Bangladesh is likely to suffer significantly though it has contributed the least to the causes of climate change. The government is faced with the challenge of doing more to fully integrate climate change concerns into Bangladesh’s sustainable development policies, in keeping with the goals of the post-2015 sustainable development goals (SDGs). The challenge now is to limit the damage, both by mitigation and adaptation measures in overall agricultural systems.
