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Temporal and spatial stability of the vegetation–climate relationship is a basic ecological assumption for pollen-based quantitative inferences of past climate change and for predicting future vegetation. We explore this assumption for the Holocene in eastern continental Asia (China, Mongolia). Boosted regression trees (BRT) between fossil pollen taxa percentages ( Abies , Artemisia , Betula , Chenopodiaceae, Cyperaceae, Ephedra , Picea , Pinus , Poaceae and Quercus ) and climate model outputs of mean annual precipitation (P ann ) and mean temperature of the warmest month (Mt wa ) for 9 and 6 ka (ka = thousand years before present) were set up and results compared to those obtained from relating modern pollen to modern climate. Overall, our results reveal only slight temporal differences in the pollen–climate relationships. Our analyses suggest that the importance of P ann compared with Mt wa for taxa distribution is higher today than it was at 6 ka and 9 ka. In particular, the relevance of P ann for Picea and Pinus increases and has become the main determinant. This change in the climate–tree pollen relationship parallels a widespread tree pollen decrease in north-central China and the eastern Tibetan Plateau. We assume that this is at least partly related to vegetation–climate disequilibrium originating from human impact. Increased atmospheric CO 2 concentration may have permitted the expansion of moisture-loving herb taxa (Cyperaceae and Poaceae) during the late Holocene into arid/semi-arid areas. We furthermore find that the pollen–climate relationship between north-central China and the eastern Tibetan Plateau is generally similar, but that regional differences are larger than temporal differences. In summary, vegetation–climate relationships in China are generally stable in space and time, and pollen-based climate reconstructions can be applied to the Holocene. Regional differences imply the calibration-set should be restricted spatially. [ABSTRACT FROM AUTHOR]

• Sedimentary DNA (sedDNA) of 201 lakes were analysed, with trn L g and h primers. • Plant sedDNA reflects well the vegetation types and related climate characteristics. • Plant sedDNA signals the dominant taxa as indicator taxa in the vegetation. Plant DNA from sediments (sedDNA) are increasingly used to reconstruct the past vegetation composition, which contrasts with the few investigations on the relationship between the plant sedDNA signal and modern vegetation. Here, we applied broad-scale terrestrial plant sedDNA metabarcoding on surface sediments from 201 lakes in eastern and northern Asia to discuss the applicability as well as the limitations of using plant sedDNA metabarcoding for palaeovegetation studies. In total, 381 terrestrial plant taxa were determined with the universal plant primers of trn L g and h. Overall, plant sedDNA approach is able to retrieve major vegetation signals. The composition of plant sedDNA reflect well the vegetation types and related climate characteristics, and it also signals which are the dominant taxa in the vegetation. Our results indicate that plant sedDNA metabarcoding could be a reliable proxy of vegetation composition at a sub-continental scale and along large environmental gradients. But certain drawbacks such as limited taxonomic resolution, biases in the relative abundance of taxa, and a generally high variability of samples from similar vegetation types need to be solved before it can be widely applied to reconstruct palaeofloras. [ABSTRACT FROM AUTHOR]