Traits related to carbon sequestration of common plant species in a Stipa grandis steppe in Nei Mongol under different land-uses

Aims Land-use change is one of the key factors affecting global carbon cycle, and plant functional traits have been widely used to study the linkage between environmental factors and ecosystem functioning. With the help of plant functional traits, we can better understand how plants respond to land-use changes. This study aims to 1) determine how plant traits related to carbon sequestration differ among different functional groups, organs and species of common plants in a Stipa grandis steppe in Nei Mongol; 2) explore the underlying impacts of four different land-use types on traits related to carbon sequestration of the studied plants.
Methods The study was conducted in Maodeng pastureland, Xilinhot, Nei Mongol. Samples of common plant species were collected in four plots, including a long-term reserved plot, a long-term free grazing plot, a 4-year enclosed plot and a 4-year enclosed plot with hay harvesting. We separated the plants into organs and determined the contents of carbon, total nitrogen, cellulose, lignin and acid detergent fiber, and then calculated the ratio of carbon to nitrogen. All data were analyzed in IBM SPSS Statistics for Windows 19.0.
Important findings There were marked differences in the traits related to carbon sequestration among different plant functional groups, species and organs. Land-uses significantly affected these traits at the three organizational levels. Four-year enclosure with hay harvesting resulted in a decrease in nitrogen content of the plants compared with other three land-use types. Both Cleistogenes squarrosa and Salsola collina were susceptible in the traits related to carbon sequestration to long-term free grazing, but their patterns of responses were reversed.