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• 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]

This paper compares results from two different environmental methods to observe past storm impacts: the back coastal barrier stratigraphical and dendrochronological archives. With a detailed historical database of the past 50 years storm observations, we discuss the combination of results from these two methods in a coastal study located in western France. The study shows that neither tree ring nor sedimentological results build a complete storm chronology by themselves. However, the combination of the two is sufficient to detect the strongest storms, which caused marine flooding. Comparing them with an accurate impact of storm chronology, extracted from written sources to test their robustness, we show that the combination of these two approaches offer a complete dataset. From this exhaustive historical sequence ranging from 1955 to 2016, three winters with major storms are highlighted in Traicts du Croisic: 1990, 1978 and 1972. Combining dendrochronology and sedimentology therefore enables a better understanding of extreme storm occurrences. [ABSTRACT FROM AUTHOR]

• Shrubs growth rings are relevant indicators of the response of alpine ecosystem to global warming. • At the high-elevation site, our results demonstrate a negative effect of snow cover duration. • At lower elevations, late frost exposure is shown to lead to growth reduction. • Global warming induced a divergence in the growth response of a dominant shrub species to climate. Enhanced shrub growth in a warming alpine climate has potential far-reaching implications, including soil nutrient cycling, carbon storage, or water and surface energy exchanges. Growth ring analysis can yield mid- to long-term, annually resolved records of shrub growth, and thereby offer valuable insights into how growth is driven by interannual climate variability. In the European Alps, dendroecological approaches have shown that dwarf shrub productivity is influenced by interannual variations of growing season temperature but results also point to a negative effect of winter precipitation on radial growth. However, as past work lacked snow cover data, links between snow cover duration, growing season length, energy availability and inter-annual shrub growth remain poorly understood. In this paper, we combined multi-decadal shrub-ring series from 49 individuals sampled at three sites along a 600-m elevational gradient in the Taillefer massif, located in the French Alps to assess growth sensitivity of long-lived and widespread Rhododendron ferrugineum shrubs to both snow cover dynamics and temperature changes. To this end, we computed structural equation models to track the response of shrub radial growth to extending growing season at 1800, 2000 and 2400 m above sea level and for two time periods (i.e. 1959–1988 and 1989–2016). The second period is marked by a significant advance in snow melt-out resulting in a regime shift highlighted at the end of the 1980s by a breakpoint analysis. At the high-elevation site, our results demonstrate a positive effect of increasing growing season length on shrub growth, which is strongly dependent on snowpack depth and snow cover duration. Conversely, at lower elevations, earlier melt-out dates and associated late frost exposure are shown to lead to radial growth reduction. Moreover, the climate signal in ring-width chronologies of R. ferrugineum portrays a weakening since 1988 – similar to a phenomenon observed in series from circumpolar and alpine tree-ring sites and referred to as "divergence". By analyzing long-term records of radial growth along an elevation gradient, our work provides novel insights into the complex responses of shrub growth to climate change in alpine environments. This paper demonstrates that R. ferrugineum , as a dominant alpine shrub species, behave as an ecological indicator of the response of alpine ecosystem to global warming. [ABSTRACT FROM AUTHOR]

• Tropical species' tree-ring patterns are diverse. • Tropical trees have a mean age of 315 years. • Rainy season is a limited factor for tree-ring growth. • The most common studied regions and tree species (families and genera) are listed. • Common approaches, techniques, applications, and limitations are presented. Tropical and subtropical forests cover only 7 % of the Earth's land surface. Yet, they host nearly half of global tree density with a high species number (∼40,000 species), store up to 25 % of global terrestrial carbon and represent one-third of net primary productivity on Earth. Over the last four decades, the study of tree growth in the tropics has gained substantial momentum, not least because of the increasing application in tropical and subtropical climatology, ecology, geomorphology, and archaeology. So far, various tropical and subtropical species have been shown to form growth rings with a regular, sometimes annual, layering that is driven by the species' sensitivity to climatic, ecological, or geodynamic variations. Here, we provide a detailed review of dendrochronology studies in the tropics indicating their (i) tree growth patterns, (ii) most common regions that have been studied preferentially and the families and genera of trees that have been employed most frequently, so as to provide an overview on the most suitable species, (iii) common approaches and techniques used in tropical and subtropical dendrochronology, (iv) different applications, and (v) limitations inherent to tree-ring research in the tropics. The paper concludes with a call for further research in this still understudied environment and provides potential perspectives for future work in the most biodiverse region of the world. [ABSTRACT FROM AUTHOR]

Tropical and subtropical forests cover only 7 % of the Earth’s land surface. Yet, they host nearly half of global tree density with a high species number (∼40,000 species), store up to 25 % of global terrestrial carbon and represent one-third of net primary productivity on Earth. Over the last four decades, the study of tree growth in the tropics has gained substantial momentum, not least because of the increasing application in tropical and subtropical climatology, ecology, geomorphology, and archaeology. So far, various tropical and subtropical species have been shown to form growth rings with a regular, sometimes annual, layering that is driven by the species’ sensitivity to climatic, ecological, or geodynamic variations. Here, we provide a detailed review of dendrochronology studies in the tropics indicating their (i) tree growth patterns, (ii) most common regions that have been studied preferentially and the families and genera of trees that have been employed most frequently, so as to provide an overview on the most suitable species, (iii) common approaches and techniques used in tropical and subtropical dendrochronology, (iv) different applications, and (v) limitations inherent to tree-ring research in the tropics. The paper concludes with a call for further research in this still understudied environment and provides potential perspectives for future work in the most biodiverse region of the world.