Demarcation of Natural Resources in Nuwara Eliya Estate at Labukale

Abstract

Digital mapping of estate sector demarcating natural and other resources is a new mission in Sri Lanka. A study was conducted to demarcate water resources, natural forest and the soil in Nuwara Eliya Estate at Labukale using GIS techniques.Required information was collected by field visits and from the Estate offices. Global Positioning System (GPS) was used to demarcate all the locations of tea lands, natural forests, water resources and other cultivable lands. In order to identify the soil physical conditions, 98 soil samples were taken from 49 locations of the estate including different land covers from surface and 20 cm depth soil. Soil samples were analyzed for determination of the soil EC and soil pH. ArcView GIS 3.2a software was used for the spatial analysis and mapping. Results of the study revealed that the extent of the tea estate is 246.7 ha. In the estate, 69% of the total extent contains tea fields while vegetable is growing on 18% and 13% belong to a natural forest. Surface soil pH of the estate ranges from 5.7-7.9 and surface soil EC ranges from 7.4 - 49.4 ps. The highest pH values and EC values observed at the low elevation of the estate at the proximity of the river. Surface soil pH and 20 cm depth soil pH showed significant difference. There were negative relationships between elevation and the soil pH as well as between soil EC and the elevation. Surface soil pH values are almost higher than the 20 cm depth soil pH values. Higher surface soil pH values can be observed at the vegetable lands. 20 cm depth soil EC values were higher than the surface soil EC. Higher EC values were observed at the tea fields. Average yield did not depend on the pH and EC values of the soil. Elevation pattern of the estate varies from 1680 m to 2110 m. The yield of tea field did not depend on the elevation of the tea fields.