mapping rice in africa and assessing the potential for development

Mapping rice in Africa and assessing the potential for

development

Sander ZwartResearcher Remote Sensing & GIS

Remote Sensing – Beyond Images14-15 December 2013, Mexico City

Short CV – Sander Zwart

Born in 1976 in the Netherlands

Wageningen:• 1994-2000 MSc Irrigation and Water Engineering• 2000-2002 MSc Geoinformation Science• 2002-2010 WaterWatch company (water resources /

remote sensing, ET mapping)

(Delft:)• 2003-2010 PhD Mapping and modelling of water

productivity

Cotonou:• 2010-present Africa Rice Center


Africa Rice Center - Introduction

• Started as 40 years ago as the West-African Rice Development Association (WARDA/ADRAO)

• Pan-African organization with member states• Goals: reduce poverty and reduce imports

through increasing rice production in Africa• Member of the CGIAR group of international

agricultural research organizations


West Africa Rice Development Association

(WARDA)


Africa Rice Center(AfricaRice)


Future


Africa Rice Center - Introduction

4 pillars:• Genetic Diversity and Improvement (rice

breeding)• Sustainable Productivity Enhancement

(rice agronomy) • Policy, Innovation Systems and Impact

Assessment (economy, sociology & impact)• RiceTIME: Training, Information Management

and Extension linkages (extension)

– major achievement: NERICA


Africa Rice Center – Modus Operandi

1. Projects are always in collaboration with National Agricultural Research Systems (NARS) + capacity building

2. Taskforces (Gender, Rice Breeding, Policy, Agronomy)

3. Rice Sector Development Hubs


Africa Rice Center – Introduction

Rice Sector Development Hubs:• Regions where research and development are

concentrated along the entire rice value chain• Participatory on-farm / real-life research• Hubs are operated by NARS; locations are

appointed by NARS• Efficient impact pathway: research answers to

demands and is tested in real conditions, adopted by development sector for scaling out


Africa Rice Center – Spatial analysis activities

Unit is operational again since 4 years• Researcher• Postdoctoral Fellow• Three research assistant• Two PhD students

Strong collaboration between IRRI and AfricaRice through CRP GRiSP – exchange of data and development of approaches


Africa Rice Center – Spatial analysis activities

1. Mapping rice and rice ecologies (upland/lowland/mangrove/deep water)

2. Mapping the potential for rice development

3. Mapping biotic and abiotic stresses in rice production systems


Spatial analysis – Mapping rice

Justification

Rice statistics are very unreliable in Africa

Rice is spatially highly dynamic compared to Asia

Rice is booming in Africa

Impact assessment AfricaRice

Figure



AfricaRice and IRRI co-organized an expert meeting in Cotonou (June 2012)

Goal: discuss the options for mapping rice using remote sensing (optical/radar) and develop a strategy for operational monitoring

Question: what methodologies exist and can they they be applied for African rice environments?



Differences between Asian and African rice environemnts


Asia AfricaIrrigated rice (80%) upland rainfed

lowland rainfedlowland irrigated (~10%)

Stable area Dynamic & expanding

30% of arable land 4% of arable land

Contiguous rice areas Fragmented

Paddy land preparation Dry land preparation

High fertilizer inputs Low fertilizer inputs


Recommendations/findings:- Radar remote sensing is best bet- Alternative method needs to be adopted- Sentinel program will likely provide high spatial

and temporal resolution imagery- Focus on monitoring rice area in Rice Sector

Development Hubs- Mapping of inland valleys and lowland to

distinguish upland from lowland



Pilot testing of radar remote sensing in two hubs:

Cosmo-SkyMed imagery is acquired every 16 days during rice season

Spatial resolution of 3m

Senegal: irrigated rice conditions (July-December)

Benin: upland and lowland rice (June-december)

Goals: mapping rice and assessing crop phenology dates (SoS and harvest)

Field validation collected (500 points)



Preliminary results December 2013


Spatial analysis – Mapping inland valleys

Inland valley

Areas suitable for rice production due to favorable hydrological conditions

Important for current and future rice production




stream

20 20 212123 23

2425m25

24 altitude (m)

Selected inland valley bottom

30m

Digital Elevation Model(2-dimensional)


Benin: IMPETUS project (Germany): +/- 100 digitized inland valleys from Benin (accomplished)

Togo: SMART-IV project: student collecting field data with GPS, 50 in Benin and 50 in Togo

Burkina Faso: existing data set from Min of Agriculture

Mali: RAP-IV project, 40 inland valleys

Sierra Leone & Liberia: RAP-IV project (planned)

GOAL: entire West-Africa mapped and validated


Spatial analysis – Mapping potential

Question what is the potential for development?

Currently only 10% cultivated

Goal: provide maps that indicate the potential for development of rice-based systems in an IV.

Users: NGO’s, government bodies (inland valley development cell, national IV development projects, etc.)



Suitability mapping is usually done with a selection of indicators that are given a value of importance based on expert knowledge

Disadvantage: not objective, biased

Random Forest is a statistical analysis tool that allows explaining the presence or non-presence without prior knowledge.



Methodology has been applied to map the potential for irrigated rice development in Laos (IRRI / Laborte et al., 2012)

Use of data sets on roads, travel distance, villages, markets, population density, soil suitability, water availability, rainfall, precipitation, etc., etc.



• On-going activity in two pilot sites in Benin.• Collection of data on inland valleys and

presence or non-presence of rice or agriculture• Building a spatial data base containing roads,

markets, travel distance, population density, villages, inland valleys, soil types, water availability, rainfall (remote sensing), etc.

Outlook: application at national level for west-African states. Implementation and validation with national partners and users.


Thank you! Merci!

Center of Excellence for Rice Research

mapping rice in africa and assessing the potential for development

Education