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The palaeoecology of Ginkgo through deep time, including its ecophysiology and heterophylly, remains poorly understood due to the limitation of quantitative methods. In this paper, we report well-preserved leaves of Ginkgo henanensis sp. nov. from the Paleocene Dazhang Formation of Luanchuan, Henan Province, China. Our understanding of the ecophysiology and heterophylly of the genus has been improved by the discovery. These fossils are distinguished by heterophyllous leaves that can range in morphology from bilobed to multi-lobed forms. Thus, unlike other Cenozoic Ginkgo with entire-margined leaves, this is the first well-established Cenozoic taxon that has exclusively lobed leaves similar to Mesozoic-type ginkgos. A useful leaf ecophysiological functional trait that offers quantitative insights into morphological heterophylly and the mechanism of leaf shape selection is the dry leaf mass per area (LMA) of Ginkgo. Leaf shape changes, including the evolution of heterophylly, are linked to functional adaptation. There are two groups of LMAs for four fossil G. henanensis specimens: 120.9 g/m2 to 131.3 g/m2, and 184.5 g/m2 to 187.4 g/m2. The results of the reconstructed fossil LMAs, which serve as quantitative evidence of G. henanensis ' heterophylly, also point to the existence of various leaf survival strategies within G. henanensis. Additionally, both groups of G. henanensis have LMAs that are higher than those of extant Ginkgo biloba , indicating that this species has a slower return ecological strategy than its current equivalent. This strategy may have helped to decrease the rate of nutrient cycling, which supported Ginkgo to thrive in a wider variety of ecological niches in the Paleocene than it does today. These findings close a knowledge gap in the evolution of Ginkgo. • Species similar to the Mesozoic multilobed Ginkgo still present in the Paleocene. • The feasibility of existing methods to reconstruct the leaf mass per area of fossil Ginkgo is tested. • Heterophylly of fossil Ginkgo are quantitatively proved. [ABSTRACT FROM AUTHOR]

• Tree ring is an ideal indicator of annual total grain production parameters. • Tree growth synchronized with grain production, and concurrent response to climate. • Reconstruction of total grain productivity based on dendrochronology. • To explore the relationship between total grain sown area and climate change. Climate change affects the growth of regional vegetation; both trees and grain crops often change concurrently, such that the annual radial growth of trees shows consistent inter-annual variations with the total grain crop productivity. However, it remains unclear whether they exhibit concurrent responses to climate factors, and that there lacks of the study on long-term high-resolution variations of grain crops productivity. This paper employs a Pinus massoniana tree-ring series from the Tongbai Mountains to analyze the correlations between tree-ring chronology, local climate data and grain productivity indicators (i.e., total sown grain areas (TSA), total grain outputs (TGO), and average grain yield per hectare (YPH)) of Henan Province in central China. The results indicate that temperature in March and August was the main limiting factor on tree growth, and the best concurrent relationship with tree growth was TSA, which has a correlation of 0.747 (p < 0.001) during 1959–2020. Therefore, a 124-year TSA series in Henan Province was reconstructed using tree-ring data from the Tongbai Mountains, which reveals there were two distinct low periods of total grain sown area in the 1920 s-1930 s and 1980 s-2000 s. There are significant cycles of about 2.57a (p < 0.01), 2.89a (p < 0.05), and 10.95a (p < 0.1), indicating that vegetation growth might be affected by large-scale climate forcing, such as ENSO (2-7a cycle) and sunspot activity (11a cycle). Overall, this study outlines a new approach to understand long-term changes in grain production, which is conducive to grain management and socioeconomic sustainability. [ABSTRACT FROM AUTHOR]