Madagascar-Antsibaré

Overview

Goals of the site in terms of:

  • Crop identification and Crop Area Estimation
  • Yield Prediction and Forecasting.

This work aims at testing the potential of the mission SENTINEL-2 to map croplands in a region of Madagascar characterized by small size fields, fragmented farmland and frequent cloud cover. The overall objective of this research is to provide new products from the future satellite mission, based on existing (SPOT, Landsat-8) or recent (PLEIADES) missions to support early warning systems for food security. This preparatory work is conducted in two steps: (i) mapping of different cropping systems from multisource data (SPOT time series, very high resolution PLEIADES images, DEM, ground data) and data mining methods (Random Forest) and (ii) estimation of agricultural production (phenological transition dates, yield).

Project Objectives

Mapping Agricultural Areas

Operational Implementation Plan

tsirabé Project Overview Implementation Plans Site Description Specific Project Objectives & Deliverables In Situ Observations EO Data Requirements Project Reports Study Team View/Print AllJECAM – Sidebar ImageOperational Implementation PlansData Collected for Crop CharacterizationField surveys were conducted in the study zone during the growing peak (end of February) of the 2014-2015 cropping seasons in order to characterize the main cropping systems. A total of 1020 GPS waypoints were registered in the study area, chosen according to their accessibility and to be as well representative of the existing cropping systems as possible. The data gathered during the field surveys concerned farmers’ practices (type of crop, use of fertilizers and irrigation). GPS waypoints were also registered on different types of non-cropped classes (natural vegetation, urban areas, water bodies…) to obtain data on the non-crop class. 199 additionally points were added to the field database for non-crop class by photo interpretation of PLEAIDES very high resolution imagery, making a total of 1219 points finally usable (860 cropped and 359 non-cropped). The boundaries of the fields (for cropped classes) / objects (for non-cropped classes) were then digitized over PLEAIDES very high resolution imagery in order to obtain a polygon database.

Scale

Estimating Crop Area

Operational Implementation Plan

Field size measurement

Estimating Crop Conditions

Operational Implementation Plan

Crop Conditions
  • Failure after germination
  • Biological Stress

Measuring Phenological Events

Operational Implementation Plan

Phenological Events
  • Seeding
  • Seedling
  • Vegetative Growth
  • Flowering
  • Fruit Development
  • Maturity
  • Harvest

Estimation of Biophysical Variables

Operational Implementation Plan

Biophysical Variables
  • Vegetation Indices (NDVI, EVI, SAVI, etc.)
  • Biomass

Forecasting Agricultural Variables

Operational Implementation Plan

During 2015 harvest season, 124 rice fields (88 irrigated, 36 rainfed) were sampled in order to obtain information on the farmers’ practices (cultivar, planting date, irrigation, fertilization, harvest date) and the yield (total biomass, dry biomass, full and empty grain yield on two plots of 1m² inside the field). The map in Figure 2 presents the location of the 2015 yield surveys.

Agricultural Variables (large scale)
  • Yield

Site Description

Landscape TopographyHilly
Typical Field Size0.03 ha
Climatic ZoneTropics, warm
Crop Details

Rice (Normal):
Calendar: October - April

Soil Type & Texture

Inorganic:

  • Clay
Soil Drainage Class
  • Moderately well drained
Irrigation Infrastructure
  • Manual irrigation
  • No irrigation (precipitation)
Other Site Specifications

In Situ Observations

Bio-mass yield

  • Crop Type(s):
  • Collection Protocol:

    Measurements on a one (1) meter square plot in each field

  • Frequency: Annual (just before harvest)

Nitrogen status(starting 2014)

  • Crop Type(s):
  • Collection Protocol:

    Measurements with a chlorophyllmeter(SPAD, Konica Minolta

  • Frequency: 6 times(one/month during growing season)

Crop type. Planting date, Harvest date, Location in tops squence

  • Crop Type(s):
  • Collection Protocol:

    In situ observation

  • Frequency: Annual

Type of crop, use of fertilizers and irrigation

  • Crop Type(s):
  • Collection Protocol:

    Fields surveys were conducted in the study zone during the growing peak (end of February) of the 2013-2014 cropping seasons, field surveys concerned farmers’practices

  • Frequency:

GPS waypoints

  • Crop Type(s):
  • Collection Protocol:

    A total of 1125 GPS waypoints (851 cropped and 274 non-cropped) were registered in the study area, chosen according to their accessibility and to be as well representative of the existing cropping systems as possible (2013-2014)

  • Frequency:

EO Data

Optical Data Requirements

  • Approximate Start Date of Acquisition: 01/10
  • Approximate End Date of Acquisition: 30/06
  • Spatial resolution: High resolution (5-20m)Very high resolution (below 5m)
  • temporal_frequency: Biweekly
  • Level of Expertise: Intermediate
  • Latency of Data Delivery:
  • Challanges:
  • SAR Data Requirements

    Passive Microwave Data Requirements

    Thermal Data Requirements

    Results

    Documents and Files

    Links to paper

    Project Reports

    Study Team

    Team Leader

  • Name: Valentine Lebourgeois
  • Affiliation: Centre de coopération internationale en recherche agronomique pour le développement
  • Affiliation Webpage: https://www.cirad.fr
  • Position:
  • Email: Valentine.lebourgeois@cirad.fr
  • Personal Webpage:
  • Phone number:
  • Postal Address:
  • Other Team Members

  • Name: Agnès Bégué
  • Affiliation: Maison de la Télédetection
  • Affiliation Webpage: https://www.teledetection.fr/
  • Position:
  • Email: agnes.begue@teledetection.fr
  • Personal Webpage:
  • Role: Member
  • Name: Stephane Dupuy
  • Affiliation: Maison de la Télédétection
  • Affiliation Webpage: https://www.teledetection.fr/
  • Position:
  • Email:
  • Personal Webpage:
  • Role: Member