Özet:
The objective of this study was to evaluate basal (BR) and specific respirations (qCO2) of soils under native
pasture and long-term cultivated soils at semiarid climate of the northern Turkey. In addition, the dependencies
of BR to soil water content and the relationship between microbial biomass C (Cmic) and qCO2 were determined
in the both ecosystems. Soil samples were collected from 0-5, 5-15, and 15-30 cm layers of native pasture and
long-term cultivated soils. Soil microbial biomass was determined using fumigation incubation method. Specific
respiration was calculated as BR/Cmic. BR varied through growth season in the both ecosystems and native
pasture generally had greater BR than long-term cultivated soil. The highest BR was observed in October at
native pasture. However, qCO2 was generally greater in long-term cultivated soil compared to native pasture.
qCO2 and Cmic were negatively correlated at all layers of both management systems. There was not a significant
dependency between soil water content and BR in Fluvaquentic Haplustolls. Thus, long-term cultivation
increased qCO2 which varied through growth season. Soil organisms under stress condition increased qCO2
compared to native pasture.