Climatic Variations - wamis.org
Transcript of Climatic Variations - wamis.org
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. ZamanBangladesh 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 pre-designed 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
Average temperature increases +0.30 °C
Mean yearly total rainfall 1075±325 mm(decreases –4.41%)
Fig. 1. Mean monthly maximum and minimum temperature in Rajshahi during 1980-2006
Fig. 2. Yearly total rainfall in Rajshahi during 1980-2007
Fig. 3. Mean monthly maximum and minimum temperature in Noakhali during1980-2006
Fig. 4. Yearly total rainfall in Noakhali during 1980-2007
Average temperature increases +0.80 °C
Rainfall variation was 2000-4800 mm
Fig. 6. Yearly total rainfall in Khulna during 1980-2007
Fig. 5. Mean monthly maximum and minimum temperature in Khulna during 1980-2006
Average temperature increases +0.55 °C
Rainfall ranges from 1100-2600 mm
Fig. 7. Mean monthly maximum and minimum temperature in Patuakhali during 1980-2006
Fig. 8. Yearly total rainfall in Patuakhali during 1980-2007
Average temperature increases +0.25 °C
Year to year rainfall variation (1800-4300 mm) was large
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 Tractin 1985 and 2007
-
Wheat (HYV)-Wheat-T.Aman
T.Aman(L/HYV)T.Aman (L/HYV)F-F-T.Aman
BoroT. Aman (HYV)
T.Aman (L/HYV)Boro-T.Aman
Chickpea (HYV)T.Aman (HYV)
Chickpea (L)Linseed (L)T.Aman (L/HYV)
Rainfed:Chickpea-T.Aman
Rainfed: Chickpea + Linseed-T.Aman
TomatoT.Aus
T.Aus-T.Aman/Tomato-T.Aus
Irrigated:
• 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.
Rainfed:
Rainfed: F-F-T.Aman
2007198520071985Remarks
Crops/varietyCropping pattern
• Experimental results revealed that in many years drought prevailed during flowering stage of T.Aman rice. As a result 11-34% yield loss occurred for local and 43-50% for modern T.Aman 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).
Technologies to mitigate drought situation of HBT
Seed priming of chickpea increased the seed yield of 20-25% over non-priming 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 storm-surge or by breaking of a coastal embankmentb) when drought occurs in pre-monsoon season, c) when drought occurs in post-monsoon seasond) if a tube-well (or other irrigation source) starts to deliver saline water during a crop growing period (Brammer, 1999)
Crops and cropping patterns with varieties in Noakhali in 1980 and 2007
Chilli (L)B.Aus/D.Aus (L/HYV)T.Aman (L/HYV)
Chilli (L)B.Aus/D.Aus (L)T.Aman (L)
Chilli-B. Aus/ D.Aus-T.Aman
Chilli-B.Aus/ D.Aus-T.Aman
Sweet potato (L/HYV)T.Aman (L/HYV)
Sweet potato (L)T.Aman (L)
Sweet potato-T.Aman
Sweet potato-T.Aman
Mugbean (L/HYV) T. Aman (L/HYV)
-Mugbean-T.Aman
Soybean (HYV)T. Aman (L/HYV)
-Soybean-T.Aman
Groundnut (HYV)T.Aman (L/HYV)
Groundnut (L)T.Aman (L)
Groundnut-T.AmanGroundnut -T.Aman
Khesari (L)T.Aus (L/HYV)T.Aman (L/HYV)
-Relay khesari-T.Aus -T.Aman
T. Aus (L/HYV)T. Aman (L/HYV)
-T. Aus- T.AmanCrop yields and cropping intensity increased due to inclusion of additional crops with their modern varieties and improved management practices
T.Aman (L/HYV)T.Aman (L)F-F-T.AmanF-F-T.Aman
2007198020071980Remarks
Crops/varietyCropping pattern
Crops and cropping patterns with varieties in Dacope, Khulna in 1980 and 2007
The cropping patterns have been changed due to use of modern rice varieties and in some extent introduction of salt tolerant rice varietiesCrop diversification has markedly increased through the intervention of modern technology
Boro (HYV)-Boro-F-F
T.Aman (L/HYV)T.Aman (L)F-F-T.AmanF-F-T.Aman
Sesame (HYV)B. Aus (HYV)T.Aman(L/HYV)
Sesame (L)T.Aman (L)
Sesame-B.Aus-T.Aman
Sesame-T.Aman
Boro (HYV)Lentil (L)T.Aman (L)
Boro-T.AmanLentil-T.Aman
B. Aus (HYV-F-B.Aus-T.Aman
T.Aman (L/HYV)T.Aman (L) F-F-T.AmanF-F-T.Aman
2007198020071980Remarks
Crops/varietyCropping pattern
Crops and cropping patterns with varieties in Patuakhali in 1980 and 2007
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.
Mungbean (HYV) Sesame (HYV)T.Aman (L/HYV)
Mungbean (L)Sesame (L)T.Aman (L)
Mungbean/ Sesame-T.Aus-T.Aman
Mungbean-T.Aman
Khesari (L)T.Aman (L/HYV)
Khesari (L)T.Aman (L)
Relay Khesari -T.Aman
Relay Khesari-T.Aman
T.Aus (L/HYV)T.Aman (L/HYV)
T.Aus (L)T.Aman (L)
T. Aus-T. AmanT. Aus-T.Aman
Sweet potato (L/HYV)Groundnut (Dhaka-1)T.Aman (L/HYV)
Sweet potato (L)Groundnut (L)T.Aman (L)
Sweet potato/ Groundnut-T.Aman
Sweet potato-T.Aman
Chilli (L)T.Aman (L/HYV)
Chilli (L)T.Aman (L)
Chilli-T.AmanChilli-T.Aman
T.Aman (L/HYV)T.Aman (L)F-F-T.AmanF-F-T.Aman2007198020071980
RemarksCrops/varietyCropping pattern
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, sorjanmethod 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 productionPopulation distributionVegetationSoil, water and animal resourcesTemperature, rainfall and natural hazards like cyclone, flooding, drought, salinity changes and erosionHuman healthIndustry, energy, infrastructure and communicationUrbanizationFood demand and supply
Impact on agricultureAgricultural crops are highly vulnerable to climate eventsOccurrence of unprecedented floodsOccurrence of flash floods Occurrence of droughts (kharif I and later part of kharifII and rabi)Emissions of nitrous oxide, carbon monoxide and nitrogen oxides from agril. residuesExcessive emission of methane gas has been contributing to the global warmingThe residual effects of climate changes have been destroying the content of organic matter in the soil and also the protein sources
Improved irrigation efficiencyCrop diversification (introduction of salt and drought tolerant variety for coastal and Barind area)Conjunctive use of surface and ground water irrigationChange in fertilization techniques (deep placement of fertilizer, hole system etc.)Coastal green belt forestry through GO-NGOs collaborationAgro-forestry developmentHomestead vegetable and agroforestry development Community forest development through GO-NGOs partnership
Following adaptation measures may be taken:
Institutional adaptationImproved of agricultural extension services and proper linkage with farmers for adoption of new technologies for those areaEnhance training program and dissemination activitiesResearch and development of salinity and drought tolerant crops and high yielding varieties Re-excavation of ponds/cannel in Barind areaChange practices (cultural and other management practices such as tillage, sorjan, relay, ICM/IPM/IPNS concept)Expanded access to creditGuidelines to incorporate climate change in future planningDevelopment of reserved /protected areas in different agro-ecological zones (coastal areas)Co-operative social forestry support services with the involvement of vulnerable women and men