Agriculture: A Most Vulnerable Sector due to Climate Change

Environment is constantly changing. With increased technical capabilities man changes his surrounding faster than ever before. However, mankind is aware that fast climate changes (anthropogenic and/or natural) have impacts on many aspects of life. The most direct economical influence of global climate change is due to its direct impact on agriculture and crop yields.  Increased intensity and frequency of storms, drought and flooding, altered hydrological cycles and precipitation variance have implications for future food availability, some coastal food-producing areas will be inundated by the seas, and food production will fall in some places in the interior.

In developing countries, 11 percent of arable land could be affected by climate change, including a reduction of cereal production in up to 65 countries, about 16 percent of agricultural GDP (FAO Committee on Food Security, Report of 31st Session, 2005).

A study published in Science suggest that, due to climate change, "Southern Africa could lose more than 30% of its main crop, maize, by 2030. In South Asia losses of many regional staples, such as rice, millet and maize could top 10%".

The 2001 IPCC Third Assessment Report concluded that the poorest countries would be hardest hit, with reductions in crop yields in most tropical and sub-tropical regions due to decreased water availability, and new or changed insect pest incidence.

In the long run, the climatic change could affect agriculture in several ways:

·         Productivity in terms of quantity and quality of crops

·         Agricultural practices, through changes of water use (irrigation) and agricultural inputs such as herbicides, insecticides and fertilizers.

·         Environmental effects, in particular in relation of frequency and intensity of soil drainage (leading to nitrogen leaching), soil erosion, reduction of crop diversity.

·         Rural space, through the loss and gain of cultivated lands, land speculation, land renunciation, and hydraulic amenities.

·         Adaptation, organisms may become more or less competitive, as well as humans may develop urgency to develop more competitive organisms, such as flood resistant or salt resistant varieties of rice.

The earth's average temperature has been rising since the late 1970s, with nine of the 10 warmest years on record occurring since 1995. In 2002, India and the United States suffered sharp harvest reductions because of record temperatures and drought. Similarly, because of higher temperatures and humidity, there could be an increased pressure from insects, fungal diseases and disease vectors. Studies have shown that higher CO₂ levels lead to reduced plant uptake of nitrogen resulting in crops with lower nutritional value. This would primarily impact on populations in poorer countries less able to compensate by eating more food, more varied diets, or possibly taking supplements.

Climate change could have a particularly severe impact on South Asia, where a large proportion of the region’s population depends on subsistence agriculture for their livelihoods.

Agricultural crop of Bangladesh is influenced by seasonal characteristics and different variables of climate such as temperature, rainfall, humidity, day-length etc. It is also often constrained by different disasters such as floods, droughts, soil and water salinity, cyclone and storm surges. Several studies indicated that climate is changing and becoming more unpredictable every year in Bangladesh. Flood and water logging in the central region, flash-flood in the northeast region, drought in the northwest and southwest region, and salinity intrusion and coastal inundation in the coastal regional would be a more acute problem in future. All of these will have an extra bearing on the agriculture sector.  

Different models predict different level of impacts for yield reduction under different climate change scenarios. The GFDL model predicted about 17 % decline in overall rice production for Bangladesh and as high as 61% decline in wheat production under 4 degree changes in temperature. The highest impact would be on wheat followed by rice (Aus variety). Of the three varieties of rice grown in Bangladesh, the Aus rice (grown during the summer, monsoon period under rain-fed conditions) seems to be the most vulnerable. The temperature impact already seen in this season in different region of Bangladesh. It is predicated that rice production will decrease in this year and people will face serious food crisis and economic loss. “We need more extensive climate research in different agroeconomic zone in Bangladesh to get actual adaptation in the context of local environment” stated Dr. Syed Hafizur Rahman, Chairman, Department of Environmental Sciences, Jahangirnagar University. 

Climate change is obvious thing, so adaption is very much important in Bangladesh to overcome the food crisis and economic loss by cost-effective ways to help poor farmers, Provide funds for infrastructure and institutional innovations, Provide funds for agricultural science and technology, allow funding mechanisms that recognize the connection between pro-poor development policies for sustainable growth and sound climate change policies, allow funding mechanisms that recognize and support synergies between adaptation and mitigation etc.