Study of spatial relationships among some soil physico-chemical properties of a field in central Italy using multivariate geostatistics

Soil variability within fields results from complex geological and pedological processes, therefore soil variables are expected to be correlated in a scale dependent way. An accurate soil characterization, taking into account soil and spatial variability, will allow the farmer to follow crop management practices fitted with the real soil situation. The study of the scale-dependent correlation structure of some variables was investigated by means of Factorial Kriging Analysis (FKA) developed by Matheron. This analysis consists: modeling of the coregionalization, analysing the correlation structure between the variables, estimating and mapping the regionalized factors. The present study was conducted in a 4-ha field located in central Italy. Soil samples were collected at 0–10 and 10–30 cm depth and were then analysed for pH, (cation exchange capacity) CEC, total N, Olsen P, exchangeable K, and Na. The analytical results were submitted to different kinds of analysis: classical statistical and geostatistical analysis which showed that plant macro- and micro-nutrients coming from fertilization had led to short-range variation, especially in Na, N, and CEC. The effects of these were superimposed on long-range processes, producing systematic patterns in soil fertility.