About this role
The
main objective of this assignment is to engage qualified individuals
("Digitizers") to develop an accurate, consistent, and
quality-controlled geospatial database of rice field and plot boundaries within
designated areas of the GCF Knuckles Project area.
Specific
objectives are to:
- Digitize
individual rice fields and plot boundaries from high-resolution
satellite imagery, basemaps, or other reference datasets designated by ICRAF.
- Produce
topologically correct and spatially accurate polygon datasets.
- Follow
standardized digitization protocols and attribute structures provided by ICRAF.
- Maintain
consistency among multiple GIS operators working simultaneously.
- Support
rapid preparation of field-level spatial data required for integration with the
AgriLook platform and related project applications.
- Ensure
that all digitized outputs undergo a transparent and systematic QA/QC process
prior to acceptance and payment.
The
Digitizer will be responsible for the following tasks:
- Review
reference imagery (high-resolution satellite imagery, Google earth imagery as
provided) and any existing cadastral border, or AI-survey area layers supplied
by ICRAF.
- Digitize
the boundary of each distinct field as a closed polygon in the specified GIS
format (e.g., Shapefile/GeoJSON/GeoPackage, per project standard), following
the field delineation and topology rules given in Section 5.
- Populate
required attribute fields for each polygon (e.g., unique field ID,
administrative division/GN division, land-use type, source imagery date,
digitizer ID/date).
- Where
assigned, cross-check digitized boundaries against ground/field survey points.
- Submit
digitized polygons in batches according to the agreed schedule, through the
designated submission platform/folder structure.
- Correct
and resubmit any polygons flagged as non-conforming during the quality
assurance review, at no additional cost, before they are counted as accepted
for payment.
- Maintain
a basic digitization log (area/tile covered, date, number of polygons
submitted) for progress tracking.
Digitization Standards and
Methodology
All
polygons must be digitized to the following standard:
- Each
polygon must represent one distinct, contiguous, single-cultivator rice field
and plot, as visible on the reference imagery.
- Boundaries
must be traced to the visible edge of the field (bund/ridge or adjacent
land-use change) at a proper digitization scale (e.g., finer than 1:500, per
project imagery resolution).
- No
overlapping polygons.
- No
unintended slivers, self-intersecting geometries, or duplicate polygons.
- Minimum
mapping unit and positional accuracy tolerance to be specified by the project
(e.g., ± [X] metres) before work begins.
- Correct
coordinate reference system (CRS) as specified by ICRAF (e.g., WGS84 / SL
national grid).
- Every
polygon carries required attributes for (field ID, division, source date,
digitizer ID).
Quality Assurance/Quality Control
(QA/QC)
To
safeguard data quality under the output-based payment model, the following
QA/QC process will apply to every batch submitted:
- Automated
checks: geometry validity (no self-intersections, no slivers), topology checks
(no overlaps/gaps on shared boundaries), CRS/format compliance, and attribute
completeness.
- Manual
sample review: a GIS quality reviewer visually compares a sample of polygons
against reference imagery for boundary accuracy and correct field delineation.
- Feedback
loop: rejected polygons are returned to the Digitizer with the specific reason
for rejection (e.g., boundary offset, merged fields, missing attribute) for
correction and resubmission.
- QA
sign-off: a batch is only marked Accepted, and therefore payable, once it
passes the applicable QA checks above.