Abstract:
Studies were made of the fertility of soils in the
Matara District by detailed chemical analysis of soil
samples collected from a variety of habitats, and
supplementary information was obtained from experiments
carried out to explore the responses of turves brought from
the field and of tomato phytometers grown in soils
representing various habitats to the addition of various
concentrations and combinations of nutrients, mainly
nitrate, phosphate and potassiumm.
o
The floristic data, collected from nearly 150 sites,
were analysed for ordination and classification using
modern multivariate techniques, and the results
demonstrated the versatility and diversity of habitats
reflecting differential degree of destruction of natural,
vegetation and resulting erosion leading to denudation of
soiIs.
The soils are generally poor in nitrogen and
phosphorus, but the amounts of potassium and minor
nutrients are adequate for optimum growth of the turves
examined and of the tomato phytometers.
Thus, the major growth-restriction is a result chiefly
of limitations of nitrogen and phosphorus as evident from
the improved growth of plants in response to the supplementary addition of these two nutrients.
Addition or deletion of potassium caused no significant
change of the performance of experimental plants so
indicating that potassium status of the soils in the Matara
District is not suboptimal.
It is concluded, therefore, that the addition of potash
fertilizer is not essential for improving the growth
performance of either natural vegetation or crops in the
Matara District.
