Effects of Substitution of Degraded Natural forests with Plantations on Soil Carbon Sequestration and Fertility in North of Iran



Land-use change has strong effects on ecosystem properties, especially on soil carbon storage and it increased global atmospheric CO2. Degradation and loss of area and quality of Hyrcanian forests are the biggest problems in these forests. One of the most important solutions to taking care of these problems is increasing plantations in these areas. Therefore, investigation of the effects of different species plantations on soil carbon sequestration is very important. So this study investigates the effect of A. velutinum and A. subcordata plantations after 18 years, on soil carbon sequestration and fertility in a region that previously was a degraded natural forest stand. In Chamestan region, two plantation stands and one natural stand were selected and 10 plots (25 m2) were established for soil sampling in each of them, then we took the combined soil samples in three depths (<15, 15-30 and 30-50 cm). Soil organic carbon and 10 soils factors according to standard methods were measured. Results were shown that the substitution of degraded natural stand with plantations of A. velutinum and A. subcordata significantly increased soil fertility. The maple plantation increased soil carbon sequestration about 33.61 (t C/ha) and also plantation with alder reduced it about 20.55 (t C/ha) compared to degraded natural stand. But these changes were not statistically significant. These results are revealed the importance of tree species planting, especially in degraded forests, and their different effects on soil carbon sequestration and fertility and also express the need to do more studies in this topic.