| Title | Continuous aridification since the mid-Holocene as the main cause of C-3/C-4 dynamics in the grasslands of northeastern China |
| Authors | Li, Nannan Xie, Manman Sack, Dorothy Dubois, Nathalie Yang, Xiuyun Gao, Guizai Li, Dehui Liu, Lidan Liu, Hongyan Leng, Chengcheng Wang, Jiangyong Liu, Baojian Jie, Dongmei |
| Affiliation | Northeast Normal Univ, Inst Peat & Mire Res, State Environm Protect Key Lab Wetland Ecol & Veg, Changchun, Peoples R China Northeast Normal Univ, Sch Geog Sci, 5268 Renmin St, Changchun 130024, Jilin, Peoples R China Aix Marseille Univ, CNRS, CEREGE, IRD,INRA,Europole Arbois, Aix En Provence, France Eawag, Swiss Fed Inst Aquat Sci & Technol, Surface Waters Res & Management, Dubendorf, Switzerland Chinese Acad Geol Sci, Natl Res Ctr Geoanal, Beijing, Peoples R China Ohio Univ, Dept Geog, Athens, OH 45701 USA Swiss Fed Inst Technol, Dept Earth Sci, Zurich, Switzerland Peking Univ, Coll Urban & Environm Sci, Beijing, Peoples R China Hunan Normal Univ, Coll Resource & Environm Sci, Changsha, Peoples R China Anyang Normal Univ, Sch Resources Environm & Tourism, Anyang, Peoples R China Jilin Normal Univ, Sch Life Sci, Siping, Peoples R China Minist Educ, Key Lab Vegetat Ecol, Changchun, Peoples R China |
| Keywords | EAST-ASIAN MONSOON CARBON ISOTOPIC COMPOSITION SUMMER MONSOON C-4 PLANTS LOESS PLATEAU PALEOENVIRONMENTAL INDICATORS PHYTOLITH TRANSPORT HOLOCENE VEGETATION ORGANIC-MATTER GREAT-PLAINS |
| Issue Date | Apr-2020 |
| Publisher | EUROPEAN JOURNAL OF SOIL SCIENCE |
| Abstract | Ecological responses to past climate change as determined from palaeorecords offer insights into responses that may accompany future climate change. In arid and semi-arid lands, the interactions between regional vegetation and climate change are not yet well understood, partly due to a lack of suitable palaeovegetation proxies that can provide accurate and continuous tracers for past vegetation dynamics. To gain a better understanding of long-term vegetation dynamics, this study employs a multiproxy approach applied to sand-palaeosol sediments of northeastern China's Songnen grasslands. Phytolith analyses and data on the stable carbon isotope composition (delta C-13) of organic matter are used to reconstruct palaeovegetation composition, namely, the changing abundance of C-3 and C-4 species, whereas a geochemical weathering index (Fed/Fet ratios) tracks past East Asian summer monsoon (EASM) intensity. The phytolith assemblages and indices and delta C-13 of the soil indicate that C-4 species' abundance has been increasing in the Songnen grasslands since the mid-Holocene, although C-3 vegetation is still dominant. Statistically significant negative correlations between the delta C-13 data and Fet/Fed ratios suggest that continuous weakening of the EASM since the mid-Holocene may be responsible for the C-13-enrichment of the sediments in the Songnen grasslands. Field vegetation surveys, modern topsoil phytoliths and delta C-13 calibration data indicate that the expansion of C-4 species since the mid-Holocene is mainly due to their ability to cope with aridity when growing season temperature is not undergoing a significant decrease. Future precipitation decreases in arid and semi-arid lands should make C-4 species more competitive in the grasslands of northeastern China. |
| URI | http://hdl.handle.net/20.500.11897/606693 |
| ISSN | 1351-0754 |
| DOI | 10.1111/ejss.12960 |
| Indexed | SCI(E) Scopus |
| Appears in Collections: | 城市与环境学院 |
