CPWF Conference: Revitalizing the Ganges Coastal Zone21-23 October 2014

Adaptation strategy for crop production in changing climate: Saline prone Barisal region

Study Team

Presented by

Md. Maniruzzaman, PhDPrincipal Scientific Officer, IWM Division

Bangladesh Rice Research Institute

M Maniruzzaman, J C Biswas, M A I Khan, G W Sarker, S S Haque, J K

Biswas

Bangladesh Rice Research Institute (BRRI), Gazipur, Bangladesh

M H Sarker, M A Rashid

Center for Environmental and Geographical Information Services

(CEGIS), Dhaka, Bangladesh

N U Sekhar, A Nemes, S Xenarios and J Deelstra

The Norwegian Institute for Agricultural and Environmental Research

(Bioforsk), Ås, Norwey

Introduction

• About 3.5 billion peoples lives on rice• About 50% fresh water is used for rice

production• Irrigated area is about 56%.

– 70% from GW & – 30% from SW

• Due to climate change: Temp increasing & sea level rising

• Frequency & magnitude of climatic events- flood, drought, storm, cyclone increasing

• Need more food from reduced land area

NCA & population growth by 2025 in Bangladesh

Coastal district: 19 (Upazila 147) 48 upazilas in 12 districts- exposed coast 99 upazilas- interior coast

Legend

0 cm SLR (Area : 9239 sq km)

88 cm SLR (Area :14468 sq km)

32 cm SLR (Area :10612 sq km)

Projected salinity intrusion due to sea level rise

Main Problem

• Increasing water & soil salinity

• Inland saline water intrusion

• Cyclone (AYLA, SIDR, RESMY, MOHASEN, storm & tidal surge

• Increasing temperature

• Short winter

• To assess the climate change impacts, analyze the implications for regional hydrology and vulnerability of rice crop production and

• To adopt sustainable crop production technology for saline prone areas of Bangladesh

Objectives

Study sites: Saline prone Barisal region

Methodology

Methodology

• Project sites: information of stakeholders, reports & literatures

• Local adaptation strategies- interview with farmers, field visits & literature search

• Climate change scenarios development:

(i) downscaling of available data by using climate model,

(ii) water availability scenarios through hydrological modeling (SWAT Model)

(iii) water requirement (net irrigation requirement) scenario using DRAS model,

(iv) crop production scenarios (productions/yield losses)

• Field demonstrations of different technologies

- Stress tolerant variety

- Water and Fertilizer management

- Crop establishment method, etc

Methodology

Initial soil nutrient status at Barisal project sites

Locations EC pH OM Total N

Mg K P B Zn

dS/m - % Meq/100 gm soil

Microgram/gm

Amtali 1.44-6.85

4.3-7.1

0.93-2.63

0.05-0.14

5.09-8.08

0.21-0.72

0.42-5.76

0.22-1.10

0.54-1.60

Kalapara 1.66-5.86

4.7-5.4

0.76-2.16

0.04-0.12

4.97-7.99

0.20-0.34

0.85-8.76

0.50-0.95

0.69-1.28

Patharghata

1.91-11.51

4.5-7.2

.83-4.17

0.05-0.24

3.32-6.56

.20-0.61

1.27-11.78

0.33-0.98

0.52-2.77

Critical values

- - - 0.12 0.50 0.12 8.00 0.20 0.60

Findings

Present and future status of climate

Temperature• Based on 30 years (1983-2012)

– Maximum annual avg. temp. = 32.7 oC– Minimum annual avg. temp. = 13.7 oC– Recorded • Maximum temp. = 38.1 oC• Minimum temp. = 8.5 oC

• Compared to 1990-2010 period• Temp. will be increased in 2100 by

– 1.0-3.0 oC in A1B scenario– 0.6-2.5 oC in A2 scenario– But based on IPCC (2013) • Minimum temp. will be increased by 1.8 oC• Maximum temp. will be increased by 3.4 oC

Rainfall

• Average annual rainfall = 1805-2039 mm

• Only 16-17% in winter season

• Based on A1B scenario 3% rainfall will be increased in 2011-2040, but 3% rainfall will be decreased in 2041-2100

• Based on A2 scenario 9-11% rainfall will be decreased in 2041-2070, but 3% will be increased in 2071-2100

• There was no concluding remarks for increasing and decreasing of rainfall

• Geophysical Fluid Dynamics Laboratory Transient (GFDL-TR) model predicted increased RF in Mar-Nov during 2050 and 2070, but Hadly center predicted decreased RF during same period

• At per RegCM3, dry period rainfall (Dec.-Feb) may increase up to 107% by 2050. If it really happens, it might hamper winter crops establishment, especially non-rice crops in optimum time. Pre-monsoon rainfall might decrease by 67% indicating increased supplemental irrigation of Kharif-I crops

Percent change in annual rainfall in study areas

Thirty years (1983-2012) daily average temp & rainfall, its variation by 2050 Barisal region

Critical temperature for sterility in some selected field crops

Name of crop Critical temp. for sterility (oC)

Reference

Rice (Oryza sativa L.) 35 BRRI, 2011

Wheat (Tritichum aestivum

L.)

30 Saini and Aspinal, 1982

Chickpea (Cicer arietinum L.) 35 Devasirvatham et al, 2012

Pea (Pisum sativum) 30 McDonald & Paulsen, 1997

Groundnut (A. hypogaea L.) 35 Prasad et al, 1999

Mustard (Brassica juncea L.) 27 Chauhan et al, 2013

Mung bean (Vigna radiata L.) 40 Tickoo et al, 19996

Tomato (L. esculentum L.) 32 Peet et al, 1998

Drought prevalence at Barisal region during 1983-2012. -1to -1.5 Slight, -1.5 to -2.0 Moderate and > -2.0 Severe drought

Water Availability by SWAT Model• Water availability will be reduced for all season: But it

will be reduced by 12-30% in Aus/Khatif-I (pre-monsoon) season

• Water availability will be slightly increased in Aman (monsoon) season

T. Aus & T. Aman yield under A1B & A2 scenarios (DRAS Model)

Crop name

% of yield increase (+) or decrease (-) from base scenario

2020s 2050s 2080s

A1B A2 A1B A2 A1B A2

T. Aus +(6 to 7) +(6 to 7) +(3 to 4) +(6 to 7) +(0 to 1) +(6 to 7)

T. Aman -(8 to 11) -(5 to 7) -(3 to 10) -(13 to 19) -(4 to 12) -(2 to 8)

Demand and surface water availability (mm) at Amtali upazila, Barguna Scenarios

Year T. Aus T. Aman Boro Surplus/DeficitDemand

SWA Demand

SWA Demand

SWA T. Aus

T. Aman

Boro

A1B Base 117 833 97 473 881 58 716 376 -823

2020s 39 950 118 486 898 55 911 368 -843

2050s 74 802 146 469 890 55 728 323 -835

2080s 109 823 116 475 919 51 714 359 -868

A2 2020s 6 772 107 388 824 65 766 281 -759

2050s 24 762 120 402 820 51 738 282 -769

2080s 31 903 104 508 859 48 872 404 -811

Net Irrigation Water Requirement (mm)

Crop Name

Base year

(1981-2010)

Change of NIR (mm)

2020s 2050s 2080s

A1B A2 A1B A2 A1B A2T. Aus 100-120 -(60 to 80) -(90 to 110) -(25 to 40) -(80 to 90) -(3 to 8) -(70 to 90)

T. Aman 80-125 +(20 to 30) +(10 to 30) +(50 to 70) +(20 to 40) +(20 to 25) +(10 to 30)

Boro 830-880 +(10 to 20) -(40 to 60) +(10 to 30) -(40 to 60) +(35 to 40) -(10 to 30)

The way for climatic adaptation• Low water demanding crop cultivation• Salt and heat tolerant variety cultivation

based on land suitability• Increasing water storage capacity by re-

excavation of canal (khal), pond etc. and cultivation of rice and non-rice crops by using this water

• Increasing capacity to combat the climatic adverse effect

Major cropping patterns & percent area coverage in study area

Locations Cropping patterns Coverage (%)

Kalapara Pulses-Fallow-T. Aman 55Rabi crops-Fallow-T.Aman 20Fallow-T. Aus-T.Aman 10Others 15

Amtali Pulses-T. Aus-T.Aman 56Fallow-T.Aus-T.Aman 34Others 10

Patharghata Fallow-Fallow-T.Aman 45Fallow-T.Aus-T.Aman 25Potato/Sunflower-Fallow-T.Aman 20Others 10

Farmers adaptation

L0cal variety

What the farmers done

Fish in gher during monsoon

What the farmers done

Rice crop in gher during winter

What the farmers done

What the farmers done

•Salt and heat tolerant variety cultivation

• Increasing water storage in canal/khal and

motivated the farmers for crop cultivation

•Motivated the farmers for low water demanding

and salt tolerant crops like wheat and mustard

•Field demonstration for modern cultivation

•Training and field days for adaptation for

climatic effect

Field activities

Water use, crop yield & water productivity in Aus, Barisal site

Field findings

Crop Mgt. Water use

(mm)

Yield (t/ha)

Water productivity(kg/ha-mm)

T. AusRM 435 3.70-4.15

(3.85)8.51-9.54

(8.85)FM 435 3.26-3.75

(3.42)7.49-8.62

(7.86)

BRRI dhan55

Water use, crop yield & water productivity in Aman season at Barisal regionRice Mgt. Water

use (mm)

Yield (t/ha)

Water productivity(kg/ha-mm)

T. Aman (145-154 days)

RM 438 4.32-4.91(4.58)

9.86-11.21(10.46)

FM 438 4.19-4.50(4.25)

9.56-10.27(9.70)

Relayed felon with BRRI dhan46

Water use, grain yield & water productivity of Boro rice at Barisal region, 2012-2013

Crop Mgt. Total water use (mm)

Yield (t/ha)

Water productivity(kg/ha-mm)

Boro Rice

RM 912-992(952)

4.47-5.20 (4.90)

4.70-5.46(5.15)

FM 982-1108(1042)

4.13-4.68(4.35)

3.96-4.50(4.17)

Crop Mgt. water use

(mm)

Yield (t/ha)

Water productivity(kg/ha-mm)

Wheat RM 150 2.0-2.5

(2.30)

13.33-16.67

(15.33)

Water use, grain yield & water productivity of wheat at Barisal region, 2012-2013

Patharghata site Amtali site

Crop Mgt. RF (mm) Total water

use (mm)

Yield

(t/ha)

Mustard RM - - 1.20-1.50

(1.30)

Water use, grain yield & water productivity of mustard at Barisal region, 2012-2013

Rice crop damaged by cyclone MOHASEN in Patharghata

BRRI dhan47 could not survivein high salinity (> 10 dS/m)

Can we overcome it?

All farmers are not interested for rice cultivation

Crop damaged by salinity

BRRI dhan47

Salinity effect may be reduced by water management, but it increase irrigation cost

Capacity building: Farmer’s training/Field days

Crop variety adaptation

Adoption of different T.Aman varieties during 2013

Adoption of different Rabi/Boro varieties during 2013

Recommendations

• Concerted efforts of all regional research & extension organizations are needed for adaptation activities,

• Revival of drainage systems,• Measurement of trapped water salinity before use for

irrigation,• Necessary steps to develop water delivery system to

cultivate crops far away from fresh water sources.

Acknowledgements

• Authors acknowledge the Ministry of Foreign Affairs, Norway/the Royal Norwegian Embassy, Dhaka for funding research activities in collaboration with BRRI, CEGIS and Bioforsk under “Climate Change Impacts Vulnerability and Adaptation: Sustaining Rice Production in Bangladesh” project

THANK YOU VERY MUCH