TY  - JOUR
A1  - Cao, Xianyong
A1  - Herzschuh, Ulrike
A1  - Ni, Jian
A1  - Zhao, Yan
A1  - Böhmer, Thomas
T1  - Spatial and temporal distributions of major tree taxa in eastern continental Asia during the last 22,000 years
JF  - The Holocene : an interdisciplinary journal focusing on recent environmental change
N2  - This study investigates the spatial and temporal distributions of 14 key arboreal taxa and their driving forces during the last 22,000 calendar years before ad 1950 (kyr BP) using a taxonomically harmonized and temporally standardized fossil pollen dataset with a 500-year resolution from the eastern part of continental Asia. Logistic regression was used to estimate pollen abundance thresholds for vegetation occurrence (presence or dominance), based on modern pollen data and present ranges of 14 taxa in China. Our investigation reveals marked changes in spatial and temporal distributions of the major arboreal taxa. The thermophilous (Castanea, Castanopsis, Cyclobalanopsis, Fagus, Pterocarya) and eurythermal (Juglans, Quercus, Tilia, Ulmus) broadleaved tree taxa were restricted to the current tropical or subtropical areas of China during the Last Glacial Maximum (LGM) and spread northward since c. 14.5kyr BP. Betula and conifer taxa (Abies, Picea, Pinus), in contrast, retained a wider distribution during the LGM and showed no distinct expansion direction during the Late Glacial. Since the late mid-Holocene, the abundance but not the spatial extent of most trees decreased. The changes in spatial and temporal distributions for the 14 taxa are a reflection of climate changes, in particular monsoonal moisture, and, in the late Holocene, human impact. The post-LGM expansion patterns in eastern continental China seem to be different from those reported for Europe and North America, for example, the westward spread for eurythermal broadleaved taxa.
KW  - China
KW  - Holocene
KW  - Last Glacial Maximum
KW  - pollen mapping
KW  - vegetation expansion
Y1  - 2015
U6  - https://doi.org/10.1177/0959683614556385
SN  - 0959-6836
SN  - 1477-0911
VL  - 25
IS  - 1
SP  - 79
EP  - 91
PB  - Sage Publ.
CY  - London
ER  - 
TY  - JOUR
A1  - Herzschuh, Ulrike
A1  - Pestryakova, Luidmila Agafyevna
A1  - Savelieva, Larissa A.
A1  - Heinecke, Liv
A1  - Böhmer, Thomas
A1  - Biskaborn, Boris
A1  - Andreev, Andrei
A1  - Ramisch, Arne
A1  - Shinneman, Avery L. C.
A1  - Birks, H. John B.
T1  - Siberian larch forests and the ion content of thaw lakes form a geochemically functional entity
JF  - Nature Communications
N2  - Siberian larch forests growing on shallow permafrost soils have not, until now, been considered to be controlling the abiotic and biotic characteristics of the vast number of thaw-lake ecosystems. Here we show, using four independent data sets (a modern data set from 201 lakes from the tundra to taiga, and three lake-core records), that lake-water geochemistry in Yakutia is highly correlated with vegetation. Alkalinity increases with catchment forest density. We postulate that in this arid area, higher evapotranspiration in larch forests compared with that in the tundra vegetation leads to local salt accumulation in soils. Solutes are transported to nearby thaw lakes during rain events and snow melt, but are not fully transported into rivers, because there is no continuous groundwater flow within permafrost soils. This implies that potentially large shifts in the chemical characteristics of aquatic ecosystems to known warming are absent because of the slow response of catchment forests to climate change.
Y1  - 2013
U6  - https://doi.org/10.1038/ncomms3408
SN  - 2041-1723
VL  - 4
PB  - Nature Publ. Group
CY  - London
ER  -