PROTECTED CARBON AND NITROGEN STOICHIOMETRY IN SOILS UNDER RED PINE AND OAK FORESTS.

Carbon and nitrogen are stoichiometrically linked in soil organic matter to influence ecosystem services. The objective of our study was to determine the impact of Red pine (Pinus brutia Ten.) and Oak (Quercus coccifera) forest vegetation on soil aggregate protected carbon and nitrogen stoichiometry in the Goksu catchment of Turkey. Soils were collected form two randomly selected composite sampling sites under the cover of about 100 years old Red pine (RP1, RP2) and Oak (Ok1, Ok2) natural forests. Soils were air-dried, fractionated into different aggregate sizes (>2 mm, <2 mm, and 2 to 0.25 to 0.25 to 0.05 mm separately), and analysed for total organic C (SOC) and N (TN) contents. The highest SOC and TN content was determined in the Ah horizons of profile RP1, RP2 and Ok1 and the A1 horizon of profile Ok2. The <2 mm aggregates contain higher SOC and TN contents than the >2 mm aggregates in the Bw horizons of all the four soil profiles. The 0.25 to 0.05 mm aggregates had higher contents of SOC and TN than that of the 2 to 0.25 mm aggregates in the Bw horizon of all the soil profiles. [ABSTRACT FROM AUTHOR]