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Key Message: The principal components of tree-ring anatomical chronologies of Scots pine proved to be much better proxy than its tree-ring width for reconstruction of climate-driven component in the regional yield of cereals Tree-ring records are often used as a proxy not only for climate, but also for other related variables. One of such applications is the reconstruction of crop yield, since both are indicators of productivity in the respective ecosystems. Recently, finer parameters of wood structure were applied to enhance the sensitivity and temporal resolution of the registered climatic signal and thus to improve the quality of tree-ring based reconstructions. This pioneering study tests cell-scale quantitative wood anatomy (QWA) of conifer tree species as a proxy for crop yield in the moisture-limited plains of Khakassia (South Siberia). Spring wheat, oats, and barley yield series generalized for rain-fed (north of the region) and irrigated (central part) fields in the steppes were compared with long-term (1807–2018) QWA series of the Scots pine (Pinus sylvestris L.) from the forest-steppe in the foothills. Chronologies of the cell radial diameter and cell wall thickness, describing the tree ring separated into 15 sectors, were obtained and indexed to remove their common exponential dependence on the number of cells per radial row in the ring. The tree-ring width alone could explain only 16.0 and 5.3% of yield variation for rain-fed and irrigated crops, respectively. Whereas, the multifactor linear regressions with stepwise inclusion of QWA chronologies explained 48.4 and 16.1%. The implementation of principal components for QWA in the models further increased the fitness to 48.9 and 23.0%. These reconstructions have climatic responses during the vegetative season similar to ones of the respective actual yield series. The reconstructed history of the low-yield years is supported by documented evidence of crop failures, droughts, and other related events. [ABSTRACT FROM AUTHOR]

ABSTRACT: A reconstruction of annual to multi‐decadal precipitation based on ring‐width of Cedrus deodara (Himalayan cedar or deodar) was carried out in the Lidder (Liddar) Valley, Kashmir Himalaya. A composite tree‐ring chronology demonstrated a significant direct relationship with April–June precipitation. A modified version of point‐by‐point regression methodology was used to reconstruct April–June precipitation since 1723 C.E. This reconstruction accounts for 40% of the total variance of the actual precipitation in the calibration period. The reconstruction shows a prolonged decadal dry period between 1822 and 1887 C.E., the driest period in the reconstruction. The wettest period occurred during the early 19th century and latter part of the 20th century. Extreme dry and wet events have been identified in the reconstruction on the basis of percentile distribution. The reconstruction was compared with documented extreme flood, famines and drought events in Kashmir Valley occurring in those 288 years. The composite 500 mb height‐anomaly maps suggest the prospect to study the long‐term atmospheric circulation variability over the Kashmir Valley and surrounding region using tree‐ring data. The impact of westerlies in the precipitation patterns was also evident in analysis of composite 500 mb height anomaly. Furthermore, the reconstruction was validated through comparison with independent records and spatial correlation with gridded precipitation and drought. [ABSTRACT FROM AUTHOR]