Climatic Variations: Farming Systems and Livelihoods in the High Barind Tract and Coastal areas of Bangladesh M. B. Islam, M. Y. Ali, M. Amin and Sk. M. Zaman Bangladesh Agricultural Research Institute, Gazipur, Bangladesh
Objective To investigate the effect of climatic variations on the farming systems and livelihoods of the people
Methodology Study areas: High Barind Tract, Rajshahi and Coastal belt of six locations: Bagerhat, Dacope of Khulna, Noakhali sadar, Subarnochar of Noakhali, Dumki and Kalapara of Patuakhali
Primary information was collected through predesigned and pre-tested questionnaire and collected data were verified through FGD Secondary information was also collected from SRDI and Barind Multipurpose Development Authority (BMDA) reports Experimental data were incorporated in this study from different reports of BARI Meteorological information/data were collected from Bangladesh Meteorological Department, Dhaka
Drought prone areas (Kharif season) Source: BARC/UNDP/FAO
Drought intensity (Rabi season) Source: SRDI
Average temperature increases +0.30 C Fig. 1. Mean monthly maximum and minimum temperature in Rajshahi during 1980-2006 Mean yearly total rainfall 1075±325 mm (decreases 4.41%) Fig. 2. Yearly total rainfall in Rajshahi during 1980-2007
Average temperature increases +0.80 C Fig. 3. Mean monthly maximum and minimum temperature in Noakhali during1980-2006 Rainfall variation was 2000-4800 mm Fig. 4. Yearly total rainfall in Noakhali during 1980-2007
Average temperature increases +0.55 C Fig. 5. Mean monthly maximum and minimum temperature in Khulna during 1980-2006 Rainfall ranges from 1100-2600 mm Fig. 6. Yearly total rainfall in Khulna during 1980-2007
Average temperature increases +0.25 C Fig. 7. Mean monthly maximum and minimum temperature in Patuakhali during 1980-2006 Year to year rainfall variation (1800-4300 mm) was large Fig. 8. Yearly total rainfall in Patuakhali during 1980-2007
Pictorial views of drought in High Barind Tract Extent of Drought
In 1985, cropping intensity of HBT was 117% (BMDA, 2006) At present, cropping intensity of this area is 216% (BMDA, 2006)
Crops and cropping patterns with varieties in High Barind Tract in 1985 and 2007 1985 Rainfed: F-F- Rainfed: Chickpea + Linseed- Cropping pattern 2007 Rainfed: F-F- Irrigated: Wheat- T.Aus-/ Tomato-T.Aus Boro- Rainfed: Chickpea- 1985 (L/HYV) (L/HYV) Chickpea (L) Linseed (L) (L/HYV) - - Crops/variety (L/HYV) Wheat (HYV) Tomato T.Aus 2007 Boro T. Aman (HYV) Chickpea (HYV) (HYV) Remarks With the development of irrigation systems the cropping patterns have been changed. Improved management practices with modern crop varieties increased the yields of different crops.
Technologies to mitigate drought situation of HBT Experimental results revealed that in many years drought prevailed during flowering stage of rice. As a result 11-34% yield loss occurred for local and 43-50% for modern rice varieties. Supplementary irrigation by harvesting run off water in a mini pond (10m x 10m x 3m) can save the yield loss of one hectare of land (Annual Progress Report, OFRD, BARI, 1991).
Seed priming of chickpea increased the seed yield of 20-25% over nonpriming under moisture stress situation of HBT
Chickpea, barley, sesame, linseed, gimakalmi, stem amaranth, coriander and mungbean were found promising for drought situation Besides these, improved crop management practices viz., mulching and minimum tillage were also found to mitigate the challenges of drought
Livelihood of the farmers has improved through intervention of modern agricultural technologies, utilization of homestead areas, plantation of fruit trees along with development of better communication
Non-saline lands are becoming saline under four circumstances; a) when they flooded by saline water during stormsurge or by breaking of a coastal embankment b) when drought occurs in pre-monsoon season, c) when drought occurs in post-monsoon season d) if a tube-well (or other irrigation source) starts to deliver saline water during a crop growing period (Brammer, 1999)
Comparison of salt affected areas between 1973 and 2000
Crops and cropping patterns with varieties in Noakhali in 1980 and 2007 1980 F-F- Groundnut - Sweet potato- Cropping pattern 2007 F-F- T. Aus- Relay khesari- T.Aus - Groundnut- Soybean- Mugbean- Sweet potato- 1980 (L) Groundnut (L) (L) Sweet potato (L) (L) - - - - Crops/variety 2007 (L/HYV) T. Aus (L/HYV) T. Aman (L/HYV) Khesari (L) T.Aus (L/HYV) (L/HYV) Groundnut (HYV) (L/HYV) Soybean (HYV) T. Aman (L/HYV) Mugbean (L/HYV) T. Aman (L/HYV) Sweet potato (L/HYV) (L/HYV) Remarks Crop yields and cropping intensity increased due to inclusion of additional crops with their modern varieties and improved management practices Chilli-B.Aus/ D.Aus- Chilli-B. Aus/ D.Aus- Chilli (L) B.Aus/D.Aus (L) (L) Chilli (L) B.Aus/D.Aus (L/HYV) (L/HYV)
Crops and cropping patterns with varieties in Dacope, Khulna in 1980 and 2007 1980 F-F- Lentil- Sesame- F-F- Cropping pattern 2007 F-F- F-B.Aus- Boro- Sesame-B.Aus- F-F- Boro-F-F 1980 (L) - Lentil (L) (L) Sesame (L) (L) (L) - Crops/variety 2007 (L/HYV) B. Aus (HYV Boro (HYV) Sesame (HYV) B. Aus (HYV) (L/HYV) (L/HYV) Boro (HYV) Remarks The cropping patterns have been changed due to use of modern rice varieties and in some extent introduction of salt tolerant rice varieties Crop diversification has markedly increased through the intervention of modern technology
Crops and cropping patterns with varieties in Patuakhali in 1980 and 2007 1980 F-F- Chilli- Sweet potato- T. Aus- Relay Khesari- Mungbean- Cropping pattern 2007 F-F- Chilli- Sweet potato/ Groundnut- T. Aus-T. Aman Relay Khesari - Mungbean/ Sesame-T.Aus- 1980 (L) Chilli (L) (L) Sweet potato (L) Groundnut (L) (L) T.Aus (L) (L) Khesari (L) (L) Mungbean (L) Sesame (L) (L) Crops/variety 2007 (L/HYV) Chilli (L) (L/HYV) Sweet potato (L/HYV) Groundnut (Dhaka-1) (L/HYV) T.Aus (L/HYV) (L/HYV) Khesari (L) (L/HYV) Mungbean (HYV) Sesame (HYV) (L/HYV) Remarks Utilization of fallow land, use of modern crop varieties, intervention of appropriate production technologies has helped in changing the cropping systems and simultaneously increased the crop yields in the areas.
Cropping intensity as well as yields of crops have increased due to use of HYVs and modern production technologies which helped for improving the livelihood of farmers of coastal belt Increased salinity has a profound negative effect on the livestock health due to decrease of fodder production because of salinity, shrimp gher, long inundation, modern rice cultivation and polluted water. The fisheries sector in the southern coastal region are very likely to face significantly yield reduction in future due to climate change Enhanced salinity and climatic hazards like SIDR have ill effect on the health of human along with increased disease incidence and sudden death
In Khulna region (secondary salinity), crop lands are converted to shrimp Gher by the rich man thus rendering the non-saline crop land to saline as a result lands are becoming unsuitable for rice or other crop cultivation With the intrusion of strong saline water, production of different crops, fruit trees, are seriously affected as a result livelihood and economy of farmers of those area are seriously hampered Moreover, Global Circulation Model results revealed that due to rise of temperature, drought and salinity/ cyclone/storm surge in Bangladesh could increase in an alarming rate in the near future
Bangladesh Agricultural Research Institute has already carried out some study on screening of crops/variety for saline areas Tolerance of rabi field crops to salinity is approximately as follows: Sweet potato > cowpea > groundnut > millets > soybean > triticale > mungbean > sesame > barley > wheat > mustard For vegetables, spices and fruits the ranking would look like this: Batishak > chilli > kangkong > garlic > indian spinach > okra > water melon > red amaranth Besides these, improved crop management practices viz. raised bed with mulch, mulching, zero tillage, sorjan method etc. were also found to mitigate the challenges of salinity and rise of temperature
Following points may be considered for impact assessment on the basis of climate change scenarios Climate influence Crop production Population distribution Vegetation Soil, water and animal resources Temperature, rainfall and natural hazards like cyclone, flooding, drought, salinity changes and erosion Human health Industry, energy, infrastructure and communication Urbanization Food demand and supply
Impact on agriculture Agricultural crops are highly vulnerable to climate events Occurrence of unprecedented floods Occurrence of flash floods Occurrence of droughts (kharif I and later part of kharif II and rabi) Emissions of nitrous oxide, carbon monoxide and nitrogen oxides from agril. residues Excessive emission of methane gas has been contributing to the global warming The residual effects of climate changes have been destroying the content of organic matter in the soil and also the protein sources
Following adaptation measures may be taken: Improved irrigation efficiency Crop diversification (introduction of salt and drought tolerant variety for coastal and Barind area) Conjunctive use of surface and ground water irrigation Change in fertilization techniques (deep placement of fertilizer, hole system etc.) Coastal green belt forestry through GO-NGOs collaboration Agro-forestry development Homestead vegetable and agroforestry development Community forest development through GO-NGOs partnership
Institutional adaptation Improved of agricultural extension services and proper linkage with farmers for adoption of new technologies for those area Enhance training program and dissemination activities Research and development of salinity and drought tolerant crops and high yielding varieties Re-excavation of ponds/cannel in Barind area Change practices (cultural and other management practices such as tillage, sorjan, relay, ICM/IPM/IPNS concept) Expanded access to credit Guidelines to incorporate climate change in future planning Development of reserved /protected areas in different agroecological zones (coastal areas) Co-operative social forestry support services with the involvement of vulnerable women and men