Spatial distribution of microbial activities in Arsuz plain soils (Hatay, Turkey)

Abstract

This study was carried out to determine spatial distribution of microbial activity in Arsuz plain soil located between the Mediterranean Sea and Amanos Mountains. This plain is selected since it is under the influence of several factors including soil types (colluvial and alluvial), deforestation, and agriculture (tillage and management). In addition, topographically, Arsuz plain narrows to the north and enlarges to the south. Its west and south part is plain while the north and east part is declined. For this purpose, a large survey study was carried out in the autumn of 2018 and soil sampling was done at 67 points in the Arsuz plain. Soil microbial activities such as soil respiration (CO2 production), dehydrogenase enzyme activity (DHA), and microbial biomass carbon (MBC) contents and some important chemical analyses such as pH, EC (1:5), and soil organic matter (SOM) were performed in soil samples. According to the results of the study, the overall average values of CO2 production, DHA, and MBC contents were determined as 181 μg CO2-C gds−1 day−1, 11.85 μg TPF gds−1, and 179 μg MBC-C gds−1, respectively. SOM content, pH, and EC (1:5) values were determined as 1.77, 8.65, and 567 μS cm−1, respectively. According to the results of this research, microbial activities in the Arsuz plain soils were found to be lower than those of fertile soils. Firstly, it is speculated that agriculture and deforestation appeared to be the main reasons for these low microbial activities. Secondly, as for the plain and large areas, heavy agricultural activities could be responsible for lower microbial activities. Finally, type of soils under colluvial effect may also assume to cause irregularities.