Journal of Agricultural Research (2020), Volume. 7, Issue (2)
Spatial Variability of Soil Fertility Distribution in Kyee Inn Village Tract, Pyinmana Township, Naypyitaw
Naing Naing Moe, Swe Swe Mar, Aung Kyaw Myint, Kyi Toe, Kyaw Ngwe
A study was conducted in Kyee Inn Village Tract, Pyinmana Township, Naypyitaw during 2017 and 2018 to generate the spatial distribution maps by evaluating soil fertility status describing chemical and physical soil properties, and to suggest the farmers for proper site-specific fertilizer management using Geographic Information System (GIS). Soil sampling was done as grid method (300 m × 300 m). The soil samples were collected from three places with a depth of 0-15 cm for each grid using Global Positioning System (GPS) to get the coordinates of sampling points from total area of 480 hectares. Samples were composited to 80 samples for conducting the analysis of soil pH, electrical conductivity, cation exchange capacity, soil organic matter, soil moisture, bulk density and total nitrogen content. Spatial distribution maps of each parameter were generated using Inverse Distance Weighted (IDW) interpolation in ArcGIS software version 10.5. Based on the descriptive results, total nitrogen and soil pH showed the highest variability and least variability with a coefficient of variation 66.84% and 5.08% and the values ranging from 0.01% to 0.33% and 5.48 to 7.58, respectively. Higher bulk density values were found with an average of 1.52 g cm-3. The result of insufficient organic matter level of 0.2% to 1.7% and the variability of soil characteristics existed largely due to the differences in management practices by the farmers, and therefore, farmers should be encouraged to adopt organic matter improvement practices for improving the long-term storage of soil fertility level in crop production.
Keywords: GIS, GPS, spatial variability, soil properties