Soil Nutrient Status Mapping Through GIS Techniques of Direct Seeding Rice Cultivating Area of Ramnad District

A semi-detailed soil survey was carried out using global positioning system (GPS) and mapped in GIS environment and the soils were characterized with respect to land forms. Spatial distribution of nitrogen, phosphorus, potassium, organic carbon and micro nutrients status were studied from 43 sites representing intensively direct seeding rice growing soils. These samples were analyzed for physical, chemical and physio-chemical properties of the soils. The soils were shallow to deep, dark yello wish brown to dark grayish brown, excessive to poorly drained, low in available nitrogen, low to medium in available phosphorus and medium to high in available potassium. It could be understood that out of 2, 06,290 ha about 54.42% alone could be considered as normal soil, 29.28% as moderately acidic and 12.40% as moderately alkaline soil types. Micro nutrient status presented that shows that in general soil status is low in zinc, iron and boron. There is an immediate need to alleviate the problem in related with soil such as the low organic matter content, low in zinc and Fe content of the soil and seasonal defects low rainfall, early drought and late rainfall, water logging, sodic and alkaline soil & non-availability of suitable crop varieties to meet the local situations. On the basis of the major constraints, appropriate practices were suggested to Ramnad district farmers for their sustainable management.