Soil quality assessment for olive groves areas of Menderes District, Izmir-Turkey

Abstract

This study was carried out to determine assessment of soil quality for olive groves areas of Akcakoy, Catalca, Efemcukuru, Gorece and Yenikoy villages in Menderes district of Izmir-Turkey. The surface soil samples (0-20 cm) were taken from 19 olive groves areas of Menderes District. Soil physical and chemical quality indicators were analyzed and classified in 4 suitability classes for olive production. In olive groves areas, soil reaction (pH) gave positive correlations with clay, exch. Ca, CaCO3 contents, and significant negative correlations with sand, available Fe, Mn and Zn contents. Soil organic matter (OM) content showed significant positive correlations with EC, P, exch. Ca and a significant negative correlation with bulk density. Electrical conductivity (EC) values gave significant positive correlations with clay, OM, exch. Ca contents. Soil quality index values for the olive groves areas ranged between 0.44 and 0.77 with a mean of 0.60. The olive groves areas at Akcakoy and Catalca villages of Menderes District were generally suitable for olive production. According to the soil quality index (SQI) values, only one of the 19 olive groves areas was found in very suitable (S1:1.00-0.75) class, the other areas were classified as 8 in suitable (S2:0.75-060), 6 in marginal suitable (S3:0.60-0.50) and 4 in non-suitable (N:<0.50) for olive growth. The most restricting soil factors for olive growth generally became low OM, low nutrient contents and high clay and sand contents than that of suggested levels. The SQI values had significant positive relations with silt content of the soils while they gave negative correlations with clay and sand contents. It indicates that moderate or loamy soil textural classes are important for high olive production. The SQI values also gave a significant positive correlation with olive yields. Evaluation of soil physical and chemical properties with a SQI value is important for assessment of olive groves areas in sustainable soil management system.