Characteristic mineralization of soil organic carbon in different successional series of broadleaved Korean pine forests in the temperate zone in China
The soil carbon cycle and global climate change are closely related to the mineralization of carbon in terrestrial ecosystems. To accurately assess the characteristics of carbon mineralization and variation in the mineralization of carbon in different succession series (mesosere series,hydrosere series,and xerosere series) in the broadleaved Korean pine forests of the Xiaoxing' an Mountains in the temperate zone of China,we measured the mineralization of carbon and the mineralization rate based on the chronosequence method. The results showed that the carbon mineralization rate and the extent of carbon mineralization in the three successional series exhibited consistent cross-sectional variation,and gradually decreased with depth. The extent of carbon mineralization in the different successional series was different. The virgin forest accumulated soil organic carbon and mineralization in the mesosere was the greatest among the three series,followed the xerosere and hydrosere series. The carbon mineralization rate of the three successional series varied with time and exhibited a consistent trend ( decreasing quickly during the first stage and gradually stabilizing). The six kinds of community-type carbon mineralization in the three successional series were significantly different. The carbon mineralization rate of the three successional series in broadleaved Korean pine forests was original forest > Betula platyphylla-Pinus koraiensis forest > Picea koraiensis-Pinus koraiensis forest > Betula costata-Pinus koraiensis forest > Quercus-mongolica-Pinus koraiensis forest > Betula davurica-Pinus koraiensis forest. Mesosere series carbon mineralization fit a nonlinear exponential better. Carbon mineralization of soil organic carbon was significantly positively correlated with soil total nitrogen and litter-fall amount in different successional series in the broadleafed Korean pine forests,and negatively correlated with soil moisture,soil bulk density,and soil pH. In short,successional histories,soil texture,and nutrient status resulted in differences in soil organic carbon mineralization of the different succession series in the broadleaved Korean pine forests.