PhD

The need for a scientific approach in inventorying and utilizing
land resources most economically and efficiently is now universally
accepted. Agricultural prosperity, to a great extent, depends on
judicious use of soils and rational application of soils data. A
reconnaissance soil survey of Onattukara region was undertaken to
study the extent and distribution of the different soils for soil

classification, land capability and irrigability classification and for
subsequent land evaluation. The study reveals that Onattukara region
extends over an area of 40,948 ha. The soil map showing the
distribution of the identified twenty soil series has been prepared.
The climatological data reveals that the soil moisture regime is
,
ustic and the soil temperature regime is isohyperthermic.
The soils have been classified as per Soil Taxonomy (U.S. Soil
Survey Staff, 1975) and Keys to Soil Taxonomy( U.S. Soil Survey
Staff, 1994 and 1996). Ten series were classified under Entisols, SIX
under Inceptisols, three under Ultisols and one under Alfisols.

Based on the inherent soil characteristics and landscape features,
the soils have been grouped into three land capability classes, nine
capability subclasses and land capability map prepared. The soils were
classified into five land irrigability classes, eight land irrigability
subclasses and land irrigability map prepared.

The soils were evaluated based on principles of land evaluation
and rating of productivity parameters. The productivity rating of the


soil propertIes agamst the productivity index for nee, coconut,
sesamum ,cassava and banana were made and conclusions arrived at.

Productivity rating shows that Kottakakam series is best suited
for rice, Palamel, best for coconut and banana, Artuva and
Mahadevikad, for sesamum and Palamel and Vallikunnam, for cassava.
On the basis of the studies carried out, a land use is proposed for the
twenty soil series of Onattukara region based on crop suitability
ratings and crop suitability map prepared for the five crops taken for
study. A proper soil survey interpretation provides information on
soil potential, productivity and limitations in their sustained use.

Soil survey information forms the major basis for land
evaluation. A thorough knowledge of the potentialities and limitations
of every piece of land is a prerequisite in its efficient utilization. A
systematic survey is essential for the evaluation and classification of
the soils based on their inherent soil characteristics, land capability,
land irrigability and land suitability.

A systematic survey and evaluation of the soils of Onattukara
region was taken up to study, interpret, classify and to show their
location and extent on base maps. It is hoped that the present study
would open up avenues for further investigations on land evaluation,
crop suitability and other management aspects for sustained use of soil
resource data to the best advantage. This will also form the basis for
microlevel planning for integrated and sustainable development of the
region under Panchayat raj.