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Rubber (Hevea brasiliensis) one o f the main plantation crops in Sri Lanka is the only
plant species cultivated com m ercially for natural rubber harvesting. N ovel system s for
harvesting have been introduced but spatial distribution o f photosynthetic potential
determining key factor for sustainable cultivation has not been properly explored. U se o f such
techniques such as Satellite Remote Sensing (R S) and Geographic Information System (GIS)
to analyse spatial and biological factors related to the productivity o f rubber plantation with
different harvesting system s is the main objective o f the present study.
Quikebird high resolution satellite im ages were used for RS analysis. Chlorophyll
content o f rubber leaves was measured using a SPAD-502 chlorophyll meter. Chlorophyll
content and satellite im ages were analysed using GIS and spatial statistical m ethods to
determine the variation in different harvesting system s. Y ield data were collected from the
study site and yield parameters were correlated w ith chlorophyll content and Norm alized
D ifference V egetation Index (N D V I) values. R esults revealed all system s exhibited
prom ising yield performance without significant deviation but slightly higher yield per
hectare per year (YPH) and dry rubber content o f latex (DRC) were recorded in quarter spiral
based once in three days (S/3 d4) and w eekly (S/2 d l 2d7) harvesting system s. Chlorophyll
content and rubber yield showed direct correlation in all system s. NDVI vs chlorophyll
showed positive correlation r2=0.65 and spatial distribution o f chlorophyll and N D V I values
demonstrated sound physiological status o f plants across the plantation with different
harvesting system s. Cost effective LIH system s showed better production trend
demonstrating relatively higher yield w hile reducing tapping cost and labour. Satellite based
remote sensing technique is an easy and efficient tool to estim ate productivity o f rubber
plantation over a large area.
