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Global historical land use scenarios, including HYDE3.2 and PJ, are widely used in global change research. However, their uncertainties have not been well evaluated. Based on the historical-documents-based Chinese historical cropland dataset (CHCD), we evaluated the uncertainties of the representative global historical land use scenarios in past-millennium cropland reconstruction in China in terms of the area and spatial pattern. The results show that apparent differences exist in cropland area at the national scale between HYDE3.2 or PJ and CHCD for the Song-Liao-Jin Era (AD 1000–1279) and the Qing dynasty to present (AD 1644–1999), with a maximum relative difference ratio (RDR) of about −35% and 112%, respectively. We detected similar differences at the provincial scale, except for Guizhou, Heilongjiang, Jilin, and Xinjiang provinces. Specifically, HYDE3.2 underestimates cropland areas of nine provinces, with an absolute difference of up to 5.2 × 104 km2, while overestimates cropland areas of ten provinces, with an absolute difference of up to 5.1 × 104 km2. As for the spatial pattern, the percentage of grids with an absolute value of RDR greater than 70% between HYDE3.2 and CHCD reach up to 54%–82%, mainly distributed in major agricultural areas, frontier areas, and geographical transition zones. In conclusion, neither HYDE3.2 nor PJ reflects China's cropland area and its past-millennium change accurately, resulting from the differences in data sources, area estimation, and spatial allocation methods. [ABSTRACT FROM AUTHOR]

Quantifying long-term and large-scale changes in cropland cover is critical for evaluating the intensity of past human activity, climate change, biodiversity loss, food security, and carbon and water cycles. This study used multiple data sources, i.e., historical reconstruction, remote sensing, statistics, and their derived products, and a combined approach for quantitative reconstruction and gridding allocation to create the Chinese Historical Cropland Dataset+ (CHCD+). Our findings showed a substantial gross change of 30.82 × 107 ha in cropland cover, equivalent to 32 % of China's land area. This represents a 3.2-fold increase compared to the net change. Such a large-scale agricultural land cover change has not been identified previously. Traditional agricultural areas, predominantly in the Yellow River and Yangtze River basins, have established a fundamental pattern for the historical development of agriculture in China. The proportion of croplands in this region consistently exceeded 70 %, reaching 90 % before the mid-Qing dynasty. We identified a two-phase pattern of historical cropland cover changes in China. Before the Qing Dynasty, there was slow growth and a substantial change in the cropland area. This has been constrained by geographical conditions, tax systems, and population size, with the gross change being six times the net change. Since the Qing Dynasty, a rapid growth and expansion phase has been observed in cropland areas, which can be explained by tax system reforms, population expansion, and the introduction of cold- and drought-resistant crops. • Cropland areas in China exhibited a prevailing expansion trend throughout the last millennium. • China's cropland experienced a gross change 3.2 times greater than the net change in the millennium. • Pre-Qing Dynasty, traditional agriculture region covered 42 % of national land, exceeding 90 % in cropland proportion. • Land policy and population size shaped cropland dynamics, imposing constraints or acting as drivers. [ABSTRACT FROM AUTHOR]

Despite the dominance of a two-generation approach to the study of intergenerational social mobility, multigenerational influences that link the characteristics of kin across three or more generations may be important in some populations. These effects include direct net effects of grandparents' socioeconomic characteristics on grandchildren, the effects of even more remote generations, the effects of family characteristics that bring extreme advantage or disadvantage at points in the past that are not uniformly tied to any specific past generation, a variety of demographic effects that both reweight socioeconomic distributions in successive generations and also incorporate multigenerational effects on demographic behavior itself, heterogeneous multigenerational effects in populations that contain more than one social mobility regime, and long-run multigenerational effects that result from mobility-fertility interactions in population dynamics. Genealogical data from the Qing Dynasty Imperial Lineage and from population registry data for Liaoning, China over the past several centuries provide illustrations of all of these types of multigenerational effects. Multigenerational influence is much more multi-faceted than previous speculations and empirical investigations have implied. [ABSTRACT FROM AUTHOR]

Binding material is a key component of painted cultural relics, and research on binding agents ("binders") is of great significance for the study of the history and preservation of cultural artefacts. In this work, our team collected 129 painted samples from 28 ancient cultural relics located in 9 provinces of China. We used an enzyme-linked immunosorbent assay (ELISA) as well as immunofluorescence microscopy (IFM) to identify proteinous binders in these samples. Our results show that 51 painted samples were found to contain animal glue, 13 samples were found to contain egg ovalbumin, and 2 samples were found to contain casein. Two mural painting samples prepared in the Ming and Qing Dynasties (14–20 century AD) from the Jiazaerjia Mountain Grottoes in Sichuan province were found to contain casein, and this is the first time that casein binders were found in Chinese painted cultural relics. On top of our detection results, this paper also reports statistics on the chronology, geographical distribution, and artwork types in which organic binders are found, and provides evidence of the use of proteinous binders in Chinese painted cultural relics. [ABSTRACT FROM AUTHOR]

Do external shocks affect local government quality and, consequently, long-term economic development? The collapse in 1911 of the Qing Dynasty in China was one of the greatest institutional shocks in world history, marking the end of more than 2,000 years of imperial rule. We exploit this shock to examine the impact of changes in historic local government quality on economic development today. By measuring variations in governance quality across 1,664 Chinese counties and examining their impact on long-term economic development, we show that historical differences in local governance quality are strong predictors of current geographical differences in economic development. This positive relationship is robust to a rich gamut of controls and checks. To further address causality issues, we instrument historical government quality with the location of military towns in the preceding Ming dynasty. The analysis shows that history has left a deep legacy on governance differences across China that determine, to a considerable extent, current Chinese regional inequalities. • Historical differences in local governance quality in China are a predictor of current differences in economic development. • Centuries of a system —the Chongfanpinan— that enshrined geographical differences in government quality still matter for local development today. • The influence of 2000 years of imperial rule is still deeply embedded in Chinese society. • Such historical influence has survived the century of political and economic upheaval that followed the demise of the Empire. [ABSTRACT FROM AUTHOR]