Pilot Multi-Site/Country Experiment Kazunori Minamikawa (NIAES) - PowerPoint PPT Presentation

2015 Asia Sub-Group Meeting of GRA-PRRG 18 September 2015 ISS-CAS, Nanjing, China Pilot Multi-Site/Country Experiment Kazunori Minamikawa (NIAES) Agnes Padre (IRRI) And other participants

MIRSA Project (Greenhouse Gas Mitigation in Irrigated Rice Paddies in Southeast Asia) 2013-14 Dry season, Pati, Indonesia Ph ilRice Hu e Un iv. A& F JGSEE/KM UTT Coordinated by I AERI  A research project funded by MAFF, Japan, from 2013 to 2018  Aiming at assessing the feasibility of GHG mitigation through water saving techniques (AWD) in irrigated rice fields  Results shows effectiveness of AWD to reduce CH 4 +N 2 O emissions

Research objective Our project aims to develop improved water management based on Alternate Wetting and Drying (AWD) that can always reduce soil-derived CO 2 -eq emission (CH 4 + N 2 O) during rice growing season from irrigated rice paddies in Asian countries by 30% compared to the conventional practice. 100 GHG 70

AWD: Alternate Wetting and Drying As far as I know, the term “AWD” is now used as a common term that denotes “water management practice during rice growing period.” In our project, the three practices are shared and tested at all the sites. 1. Continuous flooding : as reference practice 2. Safe AWD : naturally drained until the surface water table reaches –15 cm; and then irrigated… 3. Site-specific AWD : established based on scientific experience of each monitoring site (i.e., can differ in the practice among the sites) – 15 cm Water table Safe Time course

Previous annual meetings Kick-off meeting 2-4. Oct. 2013 Hue University of Agriculture and Forestry, Vietnam 2 nd annual meeting 18-19. Aug. 2014 IRRI, Philippines

Previous site visiting NIAES and IRRI colleagues have inspected all the four sites. Indonesia Thailand Philippines Vietnam

Soil Profiles VIETNAM INDONESIA PHILIPPINES THAILAND Thua Thuen, Hue Jakenan, Pati, Bansang, Maligaya, Muñoz, Prachinburi Central Java Nueva Ecija 0 cm 0 cm 17 cm 25 cm Redox horizon 80 cm 87 140 cm cm FAO: Dystric Fluvisols, USDA: USDA: FAO: Ustic Epiaquert USDA: Typic Vertic Endoaquepts Aeric Endoaquepts USDA: Eutric Vertisol Endoaquepts WET WET DRY DRY no mottles with mottles Indicates seasonal Decreasing redox oxidation in the soil condition pores

Greenhouse Mitigation in Irrigated Rice Systems in Southeast Asia Site Specificities Soil HUAF IAERI PhilRice PRRC Site Thua Thien, Pati, Central Muñoz, Nueva Bansang, Hue Java Ecija Prachinburi Soil texture loam Loam Clay Clay Clay 17.5 18.2 17 10.4 Silt 33.2 34.9 39 26.7 Sand 49.3 46.9 44 62.9 pH 4.18 6.24 6.44 4.93 Total C % 1.25 1.37 1.72 1.93 Total N % 0.068 0.08 0.101 0.18

Indonesia Thailand Philippines Vietnam

3 rd Annual Meeting of MIRSA-2 Project Tsukuba, Ibaraki, Japan Aug 24-25, 2015

Thua Thien, Hue 2014 2015 Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec Jan Feb Mar Apr May winter-spring summer-autumn winter-spring -------------wet fallow------------ Rainfall (mm) 200 150 100 50 0 water level (mm) CF 10 wet 0 -10 -20 CH 4 mg m -2 d -1 CF 2500 2000 1500 1000 500 0

Thua Thien, Hue water level (cm) AWD 10.0 wet 5.0 0.0 -5.0 -10.0 -15.0 -20.0 15 AWDS 10 5 wet 0 -5 -10 -15 S1 S2 S3 -20 Season S1 S2 S3 Water mgt. CF AWD AWDS CF AWD AWDS CF AWD AWDS CH 4 kg ha -1 512 396 429 1029 814 810 485 299 255 N 2 O kg ha -1 0.29 0.36 0.30 1.05 0.71 0.57 0.27 0.05 0.11 GWP 12.9 10.0 10.8 26.0 20.5 20.3 12.2 7.5 6.4 CO 2 eq t ha -1 % reduction 22 16 21 22 39 47

Methane fluxes 3 rd season (WS 2014 – 2015) Test of fixed effects: A CH 4 mg m -2 d -1 Effect Pr>F Trt <0.0001 2000 DAS <0.0001 CF AWD AWDS TrtxDAS <0.0001 1500 1000 500 0 -10 10 30 50 70 90 110 B Daily average water level (mm) 20 10 0 -10 10 30 50 70 90 110 -10 -20 -30 DAS

CH 4 + N 2 O Emissions in the Season 1-3 Hue, Vietnam Prachinburi, Thailand 30 2 Season 1 Season 1 Season 3 Season 3 Season 2 Season 2 25 -22% -21% Net GWP (CO 2 eq t ha -1 ) Net GWP (CO 2 eq t ha -1 ) N 2 O -23% -29% CH 4 20 +9% -15% 15 1 -16% -22% -39% 10 -47% -52% 5 -71% 0 0 CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS Jakenan, Indinesia Maligaya, Philippines 20 20 Season 1 Season 1 Season 3 Season 3 Season 2 Season 2 +33% Net GWP (CO 2 eq t ha -1 ) Net GWP (CO 2 eq t ha -1 ) +22% 15 15 -44% 10 10 -15% -61% -43% -35% -37% 5 5 +20% +22% -16% -30% 0 0 CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF: Continuous flooding; AWD: Safe AWD; AWDS: Site-specific AWD

Grain Yields in the Season 1-3 Hue, Vietnam Prachinburi, Thailand 10 10 Season 1 Season 1 Season 3 Season 2 Season 3 Season 2 Grain yield (t ha -1 ) Grain yield (t ha -1 ) 8 8 6 6 4 4 2 2 0 0 CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS Jakenan, Indinesia Maligaya, Philippines 10 10 Season 1 Season 1 Season 3 Season 3 Season 2 Season 2 Grain yield (t ha -1 ) Grain yield (t ha -1 ) 8 8 6 6 4 4 2 2 0 0 CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF AWD AWDS CF: Continuous flooding; AWD: Safe AWD; AWDS: Site-specific AWD

Conclusions • Management of AWD that will lead to optimum reduction in GWP is site specific. • Soil characteristics, rainfall patterns, and water availability need to be considered in the optimum management of AWD. • Increasing the number of drainage events or the number days without soil surface water increased reductions in GWP in 3 of the 4 sites. • AWD sometime increased N 2 O emissions in Muñoz, Nueva Ecija and Jakenan but not enough to offset CH 4 emission reductions. • The high increase in CH 4 emissions during the first 2 weeks after transplanting (before AWD could be practiced) due to the incorporation of rice stubbles, overshadowed the CH4 emission reduction at later stages.

Near-future milestone FY2014 FY2015 FY2016 FY2017 Field monitoring & support Writing papers & support Writing synthetic papers Field monitoring