Abstract:
Bearing a large economic importance, coconut is mainly cultivated in the coastal zone of Sri
Lanka due to the availability of optimum conditions for coconut growth. However, conversion
of coconut plantations into other land-uses could be observed all along the coast during the past
few decades. Therefore, this study aims at investigating the land-use changes that occurred in
coconut plantations in the western and southern coasts of Sri Lanka over two decades (1996-
2017). Two digital land-use/cover (LULC) maps of a 2km belt of the western and southern
coastal belts were obtained for the two years, 1996 and 2017, and area statistics were calculated
followed by an overlay analysis using ArcMap software. Two sample proportion test was
applied using R statistical software to test the significance of the area changes that occurred
from 1996 to 2017. The study area had 29,798 ha of coconut plantations in 1996 which has
significantly reduced down to 14,183 ha by 2017 (-52.4%, p<0.05). Moreover, overlay analysis
revealed that coconut plantations that existed in 1996 had been replaced with many other LULC
types by 2017, in particular, aquaculture, bare lands, grassland and marsh, homesteads,
settlements, rubber plantations, minor crops (e.g. oil-palm), sandy areas, scrubland and chena.
Replacement of 14,446 ha, 1,434 ha and 82 ha of coconut plantations with homesteads,
settlements and bare lands, respectively provides evidence of the reduction of economically
important crop plantations, mainly for coastal urbanization. Although several government
authorities and institutions are responsible for the production, quality improvement, support
development, and conduct research on coconut, continuous decrease of coconut plantations
shows their poor monitoring and non-interference towards protecting these areas. Therefore,
this paper emphasizes the urgent need of preserving the coconut plantations on the coastal belt
of Sri Lanka, which significantly contributes to the country’s economy. In that respect, proper
enforcement of policies to prevent unnecessary conversion of economically important land-uses
must be done by authorities to minimize such drastic changes.
