A Review of Relative Pollen Productivity Estimates From Temperate China for Pollen-Based Quantitative Reconstruction of Past Plant Cover

Abstract

Model-based quantitative reconstruction of past plant cover in Europe has shown great potential for: (i) testing hypotheses related to Holocene vegetation dynamics, biodiversity, and their relationships with climate and land use; (ii) studying long term interactions between climate and land use. Similar model-based quantitative reconstruction of plant cover in China has been restricted due to the lack of standardized datasets of existing estimates of relative pollen productivity (RPP). This study presents the first synthesis of all RPP values available to date for 39 major plant taxa from temperate China and proposes standardized RPP datasets that can be used for model-based quantitative reconstructions of past plant cover using fossil pollen records for the region. We review 11 RPP studies in temperate China based on modern pollen and related vegetation data around the pollen samples. The study areas include meadow, steppe and desert vegetation, various woodland types, and cultural landscapes. We evaluate the strategies of each study in terms of selection of study areas and distribution of study sites; pollen- and vegetation-data collection in field; vegetation-data collection from satellite images and vegetation maps; and data analysis. We compare all available RPP estimates, select values based on precise rules and calculate mean RPP estimates. We propose two standardized RPP datasets for 31 (Alt1) and 29 (Alt2) plant taxa. The ranking of mean RPPs (Alt-2) relative to Poaceae (= 1) for eight major taxa is: Artemisia (21) > Pinus (18.4) > Betula (12.5) > Castanea (11.5) > Elaeagnaceae (8.8) > Juglans (7.5) > Compositae (4.5) > Amaranthaceae/Chenopodiaceae (4). We conclude that although RPPs are comparable between Europe and China for some genera and families, they can differ very significantly, e.g., Artemisia, Compositae, and Amaranthaceae/Chenopodiaceae. For some taxa, we present the first RPP estimates e.g. Castanea, Elaeagnaceae, and Juglans. The proposed standardized RPP datasets are essential for model-based reconstructions of past plant cover using fossil pollen records from temperate China.

Relative pollen productivities of the major plant taxa of subtropical evergreen–deciduous mixed woodland in China

“…The RPP D‐ Quercus of Castanea in this study (0.17 ± 0.01) and the Ta‐pieh Mountains’ study (0.53 ± 0.03; Chen et al , 2019) are lower than the RPP D‐ Quercus from Shandong Province (2.35 ± 0.10; Li et al , 2017) and the mean RPP D‐ Quercus value in temperate China (2.21 ± 0.09; Li et al , 2018) (Table 2). The lower RPP D‐ Quercus values of Castanea may be explained by the multilayered and dense woodland structure of the Daba Mountains and Ta‐pieh Mountains (Bobiec, 2012).…”

“…In the latter case, Pinus is much more common in the study area of Zhang et al (2017) than in that of Li et al (2015) (fig. 2g and 2f, respectively, in Li et al , 2018). This may explain why the RPP D‐ Quercus of Pinus in the study by Zhang et al (2017; RPP D− Quercus = 9.71) is larger than in the study by Li et al (2015; RPP D− Quercus = 3.11), and more similar to that in the Daba Mountains (RPP D− Quercus = 8.87; this study) and the Ta‐pieh Mountains (RPP D− Quercus = 6.20; Chen et al , 2019).…”

“…The RPP D‐ Quercus values for Pinus vary significantly among studies: 8.87 (standard error = 0.80) in this study, 1.83 (0.05) in the cultural landscapes of the Shandong Province (Li et al , 2017), 3.11 (0.10) and 9.71 (0.24) in the Changbai Mountains (Li et al , 2015; Zhang et al , 2017, respectively), 5.56 (0.62) in the Taiyue Mountains (Zhang et al , 2017), and 6.20 (0.11) in the Ta‐pieh Mountains (Chen et al , 2019). The synthesized mean value is 3.54 (0.09) in temperate China (Li et al , 2018) (Table 2). These differences may be due to between‐region variations in climate, Pinus species composition and landscape/vegetation structure (dense woodland, semi‐open woodland and open landscape).…”

“…Many studies have shown that the RPP values for the same pollen taxon may be significantly different among regions (e.g. Broström et al , 2004; Xu et al , 2014; Li et al , 2018). To compare this study's RPP estimates for Pinus , Castanea , Juglandaceae, Rosaceae, Fabaceae, Poaceae and Cyperaceae relative to D‐ Quercus with earlier published RPP values for which D ‐Quercus is not thge reference taxon (Li et al , 2017, 2018), we have recalculated the values in Li et al (2017, 2018) to RPP values relative to D‐ Quercus .…”

“…While the REVEALS model estimates regional vegetation composition within a 50–100‐km radius using pollen records from large sites or multiple small sites, the LOVE model estimates local vegetation composition within the relevant source area of pollen (RSAP; Sugita, 1994) of small sites. Thus far, RPPs have been estimated and used in LRA applications primarily in temperate woodland and grassland [see syntheses of RPPs for Europe by Broström et al (2008) and Mazier et al (2012), and for China by Li et al (2018), and REVEALS applications by, fope example, Trondman et al (2016), Dawson et al (2018) and Li et al (2020)}. Many research questions of interest to palaeoecologists require quantified plant cover values, but the REVEALS and LOVE models have not been applied in subtropical China due to the lack of values for pollen productivity.…”