Managing agricultural inputs for climate change adaptation
Climate change is changing most of our traditional agricultural practices as the seasonal cycle and rainfall pattern have changed, droughts have become more frequent, violent stresses of cyclones, earthquakes, prolonged floods, salt water intrusion are increasing day by day. The average temperature has increased in the summer while winter season has shortened. There are some projections about climate change that are matter of concern for Bangladesh such as: temperature would rise 1.30 C by 2030 and 2.60 C by 2070, the sea level rise would be up to three feet and a greater part of the costal area would be inundated. As a consequence 17 percent of total cultivable land would be affected. Three core people would lose their farms and homestead. Threatening the richest and most productive region of the country, sea level rise could have dramatic consequences for the economy of the country. Increased flooding from glacial melt, more intense monsoons, or more intense cyclones could also adversely affect agriculture in near term by periodically inundating much of farm land. Sea level rise under climate change would also result in saline intrusion into the river system. Several hundred thousand tons of grain production could be lost as a result of increased salinization from sea level rise. The Global Climate Risk Index 2009 showed Bangladesh as the most vulnerable to extreme weather events as a result of climate change. World Resources Institute (WRI) said, “impacts of climate variability and change cause an additional risk for agriculture”. Moreover, agricultural production is already under pressure from increasing demands for food. In this regard, the present writeup tries to find out possible alternatives of agricultural inputs to ensure expected yield of agricultural crops.
Agricultural inputs include seeds, seedlings, irrigation water, fertilizers and pesticides, land, capital, agricultural equipment etc. Some important inputs management are discussed below:
Irrigation management: The continued trend of more frequent and intense droughts and variations in rainfall due to climate variability and change may have significant impacts on agriculture. The rate of depletion of groundwater is increasing day by day. Production of boro rice and winter vegetables by natural water or surface water are being affected on regular basis. Rain fed agriculture (specially aus and aman rice) has mostly changed into irrigated agriculture. So, we must have the provision of irrigation throughout the year. Some possible strategies for managing climate variability and droughts are:
i) traditional practices such as pond excavation, retention of rainwater in mini pond or in 9´x6´x3´size pit at any corner of the land to provide supplemental irrigation.
ii) moisture conservation through mulching by straw, water hyacinth, rice husk, polythene etc
iii) governmentsupported practices such as deep tube well and shallow tube well facilitated irrigation with subsidy in fuel and electricity.
iv) introducing early maturity, shortduration, and droughttolerant crop varieties
v) following AWD (Alternate Wetting and Drying) method for rice cultivation
vi) alternative adaptation practices such as integrated croplivestock-fish farming systems, multiple cropping systems and homestead gardening etc.
Fertilizer management: Climate change may change our fertilizer management. Research revealed that an increase of atmospheric carbon dioxide reduces the nitrogen uptake by plants or crops. Moreover, fertilizer management is not same for irrigated agriculture and non-irrigated agriculture. Use of USG (Urea Super Granule) in wetland rice cultivation is a popular method now. But, if water crisis arised, this method will not be effective fully. Then, normal urea will have to be used again. So, we should not use USG in drought prone area or in sandy soils. Use of organic matter or organic manure should be popularised to increase water-holding capacity of the soil.
Seed or seedling management: Cyclones, storm surges, prolonged floods and droughts may cause serious crop damage any time. So, provision of extra seeds and seedlings must be there in disaster prone areas so that affected crops could be covered up. During flood floating seedbed, during drought dry seedbed of aus and aman rice may be effective measures. Government should provide improved method of seed processing and storage. Effective farmers training could be arranged for the target group.
Labour management: Due to increase of atmospheric carbon dioxide C3, weeds occur that are more harmful for crops. Moreover, air temperature rise causes higher incidence of pests. To control higher incidence of pests and weeds more labours are required. But, high cost of labour, lack of skilled labour, going abroad for better income by our labours are major problems in labour management. So, we need to depend on mechanized agriculture more and more. That will save time, reduce cost and make operations easy.
Pest management: Pest infestations and disease infections of crops are increasing day by day due to global warming. Again, lower night temperature with foggy weather and higher day temperature lead to severe blight disease. So, pest and disease tolerant and resistant crops and varieties, GM (Genetically Modified) crops with pest tolerant characteristics should be used. Community Agriculture Clinic may be established to identify and control pest and disease attacks.
Appropriate crop or variety selection: Cultivation of existing crops or any specific variety of a popular crop may not be possible following current cropping patterns or cropping systems due to any sudden and tremendous environmental change. Such as wheat cultivation will be impossible if average winter temperature increases 20 C in Bangladesh. Then, wheat will have to be replaced by other crops. Maize, sweet potato may be the suitable alternatives or any other variety of wheat may be introduced that can tolerate high temperature.
Several lakh tons of grain production could be lost as a result of increased salinization from sea level rise. In this regard, salt tolerant crops or variety should be cultivated. It's a matter of hope; Bangladesh Institute of Nuclear Agriculture Research (BINA) has released two salt tolerant aman rice varieties (BINA-8, BINA-9) which showed positive results in last aman season. Bangladesh Rice Research Institute (BRRI) is going to release a salt tolerant rice variety for which field trial is going on. In case of prolonged flood any variety that can persist for long in submerged condition may be cultivated. BRRI has released two flood tolerant varieties (BRRI dhan 51, BRRIdhan 52) that can sustain at least two weeks of submersed condition.
Besides, late varieties of aman rice (BR 22, BR 23, BRRIdhan 46) can be cultivated just after the flood water recedes till mid October (Ashwin). Similarly, drought tolerant crops (jujube, pineapple and other fruits, maize, country bean etc and (BRRI dhan 42, BRRIdhan 43) and early maturity variety crops (BRRIdhan 33, BRRIdhan 39,) may be cultivated in drought prone areas.
Capital management: Cost of production increases due to abovementioned problems of climate change. So, easy access to agriculture credit is highly desirable the part of affected farmers. Interference of middlemen in loan distribution must be stopped. Rehabilitation program for severely affected people should be under taken. Subsidy for agricultural inputs may be another option. It is important to mention that the present government is not oblivious of the matter. Prices of non-urea fertilizer have been reduced, diesel subsidy will be provided to the marginal farmers directly by bank check in the upcoming Boro season as like earlier year.
Ensuring easy access to information: We should ensure easy access to information specially those related to production and distribution of agricultural products and inputs. Required information: the reasons of climate change, possible impacts and damages, approximate time of disasters, pest and disease incidences, possible disaster prone areas and target groups, necessary actions to be taken etc must be provided to the farmers. Effective early forecasting method should be strengthened. Awareness building programme for target groups may be taken immediately. Community Radio may be an effective tool for these purposes. Length of agricultural programmes must be extended on TV and radio channels. Facilities of ICT or e-agriculture like AICC (Agriculture Information and Communication Centre) should be provided throughout the country for all farmers. Such centres also may be arranged as community agriculture clinic.
From the above discussion we find that availability of natural resources are decreasing, intensity of natural disasters are increasing, inputs management is becoming difficult resulting in high cost of production due to climate change and climate variability. Besides the above mentioned practices some recommendations might be helpful to ensure expected yield of agricultural crops:
-follow the latest technologies, approved methods of cultivation, location and time specific agricultural practices (mulching, zero tillage etc)
-cultivate suitable high yielding varieties, modern varieties, GM crops (Genetically Modified) and Hibrid crops.
-use pest and disaster tolerant / resistant crops or varieties.
-increase cropping intensity.
-change land topography for higher yield.
-ensure effective forecasting of possible natural disaster.
-take appropriate disaster preparedness planning.
-carry out research on adaptability of new crops and varieties, and on adaptation by affected people.
Conclusion: Bangladesh is seriously vulnerable to climate-induced hazards although there are so many controversies about climate change. Role of Bangladesh is very limited in this regard (change), but she will have to suffer and face the tremendous impacts of climate change. There is no panacea to overcome the problems. Therefore, it will be wise for us to adapt ourselves with the changing environment with our limited resources.