Effects of converting natural grasslands into planted grasslands on ecosystem respiration: a case study in Inner Mongolia, China
ZHANG Meng, LI Xiaobing*, WANG Hong, DENG Fei, LI Xu, MI Xue
State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Resources Science and Technology, Beijing
Normal University, Beijing 100875, China
Effects of converting natural grasslands into planted grasslands on ecosystem respiration: a case study in Inner Mongolia, China
ZHANG Meng, LI Xiaobing*, WANG Hong, DENG Fei, LI Xu, MI Xue
State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Resources Science and Technology, Beijing
Normal University, Beijing 100875, China
摘要 With increasingly intensifying degradation of natural grasslands and rapidly increasing demand
of high quality forages, natural grasslands in China have been converted into planted grasslands at an
unprecedented rate and the magnitude of the conversion in Inner Mongolia is among the national highest
where the areal extent of planted grasslands ranks the second in China. Such land-use changes (i.e.,
converting natural grasslands into planted grasslands) can significantly affect carbon stocks and carbon
emissions in grassland ecosystems. In this study, we analyzed the effects of converting natural grasslands
into planted grasslands (including Medicago sativa, Elymus cylindricus, and M. sativa+E. cylindricus) on
ecosystem respiration (Feco) in Inner Mongolia of China. Diurnal Feco and its components (i.e., total soil
respiration (Fts), soil heterotrophic respiration (Fsh) and vegetation autotrophic respiration (Fva)) were
measured in 2012 (27 July to 5 August) and 2013 (18 July to 25 July) in the natural and planted grasslands.
Meteorological data, aboveground vegetation data and soil data were simultaneously collected to analyze
the relationships between respiration fluxes and environmental factors in those grasslands. In 2012, the
daily mean Feco in the M. sativa grassland was higher than that in the natural grassland, and the daily mean
Fva was higher in all planted grasslands (i.e., M. sativa, E. cylindricus, and M. sativa+E. cylindricus) than in the
natural grassland. In contrast, the daily mean Fts and Fsh were lower in all planted grasslands than in the
natural grassland. In 2013, the daily mean Feco, Fts and Fva in all planted grasslands were higher than those
in the natural grassland, and the daily mean Fsh in the M. sativa+E. cylindricus grassland was higher than that
in the natural grassland. The two-year experimental results suggested that the conversion of natural
grasslands into planted grasslands can generally increase the Feco and the increase in Feco is more
pronounced when the plantation becomes more mature. The results also indicated that Fsh contributed
more to Feco in the natural grassland whereas Fva contributed more to Feco in the planted grasslands. The
regression analyses show that climate factors (air temperature and relative humidity) and soil properties
(soil organic matter, soil temperature, and soil moisture) strongly affected respiration fluxes in all
grasslands. However, our observation period was admittedly too short. To fully understand the effects of
such land-use changes (i.e., converting natural grasslands into planted grasslands) on respiration fluxes,
longer-term observations are badly needed.
Abstract：
With increasingly intensifying degradation of natural grasslands and rapidly increasing demand
of high quality forages, natural grasslands in China have been converted into planted grasslands at an
unprecedented rate and the magnitude of the conversion in Inner Mongolia is among the national highest
where the areal extent of planted grasslands ranks the second in China. Such land-use changes (i.e.,
converting natural grasslands into planted grasslands) can significantly affect carbon stocks and carbon
emissions in grassland ecosystems. In this study, we analyzed the effects of converting natural grasslands
into planted grasslands (including Medicago sativa, Elymus cylindricus, and M. sativa+E. cylindricus) on
ecosystem respiration (Feco) in Inner Mongolia of China. Diurnal Feco and its components (i.e., total soil
respiration (Fts), soil heterotrophic respiration (Fsh) and vegetation autotrophic respiration (Fva)) were
measured in 2012 (27 July to 5 August) and 2013 (18 July to 25 July) in the natural and planted grasslands.
Meteorological data, aboveground vegetation data and soil data were simultaneously collected to analyze
the relationships between respiration fluxes and environmental factors in those grasslands. In 2012, the
daily mean Feco in the M. sativa grassland was higher than that in the natural grassland, and the daily mean
Fva was higher in all planted grasslands (i.e., M. sativa, E. cylindricus, and M. sativa+E. cylindricus) than in the
natural grassland. In contrast, the daily mean Fts and Fsh were lower in all planted grasslands than in the
natural grassland. In 2013, the daily mean Feco, Fts and Fva in all planted grasslands were higher than those
in the natural grassland, and the daily mean Fsh in the M. sativa+E. cylindricus grassland was higher than that
in the natural grassland. The two-year experimental results suggested that the conversion of natural
grasslands into planted grasslands can generally increase the Feco and the increase in Feco is more
pronounced when the plantation becomes more mature. The results also indicated that Fsh contributed
more to Feco in the natural grassland whereas Fva contributed more to Feco in the planted grasslands. The
regression analyses show that climate factors (air temperature and relative humidity) and soil properties
(soil organic matter, soil temperature, and soil moisture) strongly affected respiration fluxes in all
grasslands. However, our observation period was admittedly too short. To fully understand the effects of
such land-use changes (i.e., converting natural grasslands into planted grasslands) on respiration fluxes,
longer-term observations are badly needed.
the National Basic Research Program of China (2014CB138803), the National
Natural Science Foundation of China (31570451), and the Program for Changjiang Scholars and Innovative
Research Team in University (IRT1108). We thank the staff of the Duolun Grassland Research Station, Inner
Mongolia, and LIN Guohui and ZHAO Shijie for their help during the field observations.
通讯作者: LI Xiaobing
E-mail: xbli@bnu.edu.cn
引用本文:
ZHANG Meng,LI Xiaobing,WANG Hong等. Effects of converting natural grasslands into planted grasslands on ecosystem respiration: a case study in Inner Mongolia, China[J]. Journal of Arid Land, 2017, 9(1): 38-50.
ZHANG Meng,LI Xiaobing,WANG Hong et al. Effects of converting natural grasslands into planted grasslands on ecosystem respiration: a case study in Inner Mongolia, China[J]. Journal of Arid Land, 2017, 9(1): 38-50.
2017, Vol. 9 
