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Check dams on the Chinese Loess Plateau (CLP) have captured billions of tons of eroded sediment, substantially reducing sediment load in the Yellow River. However, uncertainties persist regarding the precise sediment capture and the role of these dams in Yellow River flow and sediment dynamics due to the lack of available spatial distribution datasets. We produced the first vectorized dataset of silted land formed by check dams on the CLP, combining high-resolution and easily accessible Google Earth images with object-based classification methods. The accuracy of the dataset was verified by 1947 collected test samples, and the producer's accuracy and user's accuracy of the dam lands were 88.9% and 99.5%, respectively. Our dataset not only provides fundamental information for accurately assessing the ecosystem service functions of check dams, but also helps to interpret current changes in sediment delivery of the Yellow River and plan future soil and water conservation projects. [ABSTRACT FROM AUTHOR]

Soil conservation is of global importance, as accelerated soil erosion by human activity is a primary threat to ecosystem viability. However, the significance and role of soil conservation in reshaping landscape carbon (C) accounting has not been comprehensively integrated in the terrestrial C sink. Here, we present the first integrated assessment of the modified terrestrial C sink and aquatic C transport due to soil conservation for the semiarid Chinese Loess Plateau (CLP), the world's most vulnerable region to soil erosion. We show a surprisingly low terrestrial‐aquatic C transfer that offset the terrestrial net ecosystem productivity by only 7.5%, which we attribute to the effective implementation of soil conservation practices. Despite the highest soil erosion, the semiarid CLP acts as effective C sink at 43.2 ± 22.6 g C m−2 year−1, which is comparable to temperate forest in absorbing atmospheric CO2. Moreover, C burial in reservoirs has created an additional anthropogenic C sink of 2.9 ± 1.1 g C m−2 year−1. Our findings indicate that effective soil conservation can significantly increase landscape C sequestration capacity. The co‐benefits of soil conservation in erosion control and C sequestration have important implications for policy makers in other regions undergoing increasing erosion intensity to pursue environmental sustainability. Plain Language Summary: Aquatic export of terrestrial carbon (C) plays a significant role in modulating the magnitude of terrestrial C sink. Previous estimates of terrestrial C sink may be overestimated because not all C losses across heterogeneous landscapes are accurately determined and properly accounted for. This is particularly possible for catchments with high erosion and terrestrial‐aquatic C transfer potential. Meanwhile, soil conservation can greatly modify landscape C sequestration capacity. Thus, a more comprehensive assessment of net landscape C budget is needed that integrates aquatic export of terrestrial C while considering the role and significance of soil conservation. For the Chinese Loess Plateau in semiarid climates that once characterized the world's high soil erosion rate, we show a surprisingly low aquatic C transfer that offset the terrestrial C sink by only 7.5%, due largely to successful soil conservation in the past decades. Our findings suggest that effective implementation of soil conservation practices can substantially reduce terrestrial‐aquatic C transfer and enhance the landscape C sequestration capacity. Key Points: The magnitude of terrestrial‐aquatic C transfer in influencing landscape‐scale C balance on the Chinese Loess Plateau (CLP) is assessedThe low reduction of terrestrial C sink by terrestrial‐aquatic C transfer on the CLP is largely due to soil conservationEffective implementation of soil conservation can substantially reduce terrestrial‐aquatic C transfer and enhance landscape C sink capacity [ABSTRACT FROM AUTHOR]

Introduction: Obesity in patients undergoing hemodialysis is common. However, there is limited information on the relationship between obesity types defined by the combined body mass index (BMI) and waist circumference (WC) classification criteria and all-cause mortality in Chinese hemodialysis patients. Our objective was to determine the association between obesity types and all-cause mortality in hemodialysis patients., Methods: We conducted a prospective cohort study including patients from 11 hemodialysis centers in Beijing. According to the World Health Organization's standards, patients were classified into 2 categories with WC and 4 categories with BMI and then followed up for 1 year. Kaplan-Meier survival analysis was used to compare the difference in the cumulative survival rate in different BMI and WC groups. A multivariate Cox regression analysis was used to determine the association between different types of obesity and all-cause mortality., Results: A total of 613 patients were enrolled, the mean age was 63.8 ± 7.1 years old, and 42.1% were women. Based on the baseline BMI, there were 303 (49.4%) patients with normal weight, 227 (37.0%) with overweight, 37(6.0%) with obesity, and 46 (7.5%) with underweight. Based on the baseline WC, 346 (56.4%) patients had abdominal obesity. During a median follow-up of 52 weeks, 69 deaths occurred. Kaplan-Meier plots demonstrated a significant association of BMI categories (log-rank χ2 = 18.574, p <0.001) and WC categories (log-rank χ2 = 5.698, p =0.017) with all-cause death. With normal BMI and non-abdominal obesity as a reference, multivariate Cox regression analysis results showed that obesity (HR 5.36, 95% CI, 2.09-13.76, p <0.001), underweight (HR, 5.29, 95% CI, 2.32-12.07, p <0.001), normal weight combined with abdominal obesity (HR 2.61, 95% CI, 1.20-5.66, p =0.016), and overweight combined with abdominal obesity (HR 1.79, 95% CI, 1.03-3.73, p =0.031, respectively) were significantly associated with higher risks of all-cause mortality., Conclusion: Our study indicated that abdominal obesity is common and associated with all-cause mortality among Chinese hemodialysis patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Shi, Guo, Ye and Luo.)