| Summary: | The objective was to examine soi1-plant relationships on thirty soils from the Candacraig and Glenbuchat area in Aberdeenshire, Scotland, by chemical, biological and statistical techniques. Laboratory, glasshouse, and field methods of estimating soil nutrient supply to plants by measuring quantity, intensity and rate factors of elements in the soil and by making measurements on actual plants were reviewed. A classification was then made of multivariate statistical techniques and the advantages of these techniques, in particular factor analysis when used in situations in which emphasis is not on any one variable, over classical statistical techniques were discussed. A preliminary experiment to estimate the precision and accuracy of. determining Fe', Zn, Cu, Ni arid Cr by atomic absorption spectrophotometry and A1 and'Kn colorimetrically was successfully concluded. A correlation coefficient matrix based on forty six soil variables reflecting IT, P, K, Ca, Iwg, Na, Fe, En, M, Cr, Al, Zn, and Cu supply, (obtained from thirty soils series developed on parent materials ranging from acid to ultrabasic) and sixty eight plant variables (obtained from-a glasshouse experiment in which lime and fertilizer were added in a factorial treatment structure) was computed. This matrix was analysed into factors which however remained unidentified. Significant simple and multiple regression equations we re calculated, and the ' .1 effects of soil, lime, fertilizer and their interactions on nutrient contents, uptakes and dry matter production of ryegrass were shown. The following major findings emerged from the study: (I) There is a simple basic pattern of relationships to explain the complex correlation coefficient matrix in terms of six to seven factors. (II) Plant growth was predictable from measurements on the untreated soils, and the prediction of dry matter production was considerably improved when more than one soil variable was considered, (ill) The soils under study are of rather low nutrient status and respond well to complete fertilizers. (IV) Lime was very beneficial on the serpentine soils though it tended to depress yield when applied with, fertilizer on the non-serpentine soils.
|
|---|
