Soil, representing a continuum of diversified genetic processes and being one of the biggest natural heritages of mankind, deserves greater consideration than merely as a medium of plant growth. Plethora of evidence has accumulated stating that soil properties vary across farm fields, causing spatial variability in crop yields (Rockstrom et al., 1999; Gaston et al., 2001).
Conventional blanket use of fertilizer not only reduces nutrient use efficiency but also causes nutrient imbalances in soil, resulting in decreased crop yields (Ladha et al., 2005). Soil fertility evaluation in researcher-managed plots, wherein technologies emerge, requires a unified approach, and the results can be successful only if the evaluation is a continuous process.
There are various techniques for soil fertility evaluation, of which soil testing is the most widely accepted tool in the world (Havlin et al., 2010). Spatially and temporally dynamic soil management practices are important factors in a successful site-specific management strategy. For studies on the spatial distribution pattern of soil properties, techniques such as conventional statistics and geostatistics are widely applied (Liu et al., 2006).
The advent of information technology has provided tools like the Global Positioning System (GPS) and Geographical Information System (GIS), which help in collecting a systematic set of geo-referenced samples and generating spatial data about the distribution of nutrients (Sharma, 2004).
At Coconut Research Station, Aliyar Nagar, research on crops of varying phenology and variable nutrient demands, viz., coconut, groundnut, paddy, cocoa, pepper, tomato, and brinjal, are in vogue. Knowledge of the native soil fertility of the farm is imperative for efficient nutrient management and for correlating research findings generated through various research trials.
Hence, the study was framed with the main objective to explore, document, and map the spatial variability of soil macronutrients (N, P, and K) in Coconut Research Station, Aliyar Nagar.