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Background: Soil enzymes regulate terrestrial nutrient cycles, and their activities are sensitive to environmental change. Facing climate warming, there are still contradictions over soil enzymes of different soil types in response to climate warming. Aims: The present study aims to reveal the impact of elevated temperature on soil properties. Specifically, we intended to explore the relationship between the activity of soil enzyme and soil property facing elevated temperature across soil types. Methods: A long‐term warming experiment was conducted to assess the possible responses of three enzymes (urease, phosphatase, and sucrase) to elevated temperature across 12 soil types. These soils were collected across China and transported to Nanjing in 2016. Free air temperature increase system with an infrared radiation heater was used to elevate the air temperature by 2°C in elevated treatment (eT). Wheat–soybean continuous rotation was cultivated in the long‐term experiment field since 2016. Enzyme activities, soil pH, soil organic carbon, available nitrogen (AN) and phosphorus (AP), and water content were measured after wheat harvest in 2021. Results: Warming significantly increased the activities of urease and sucrase in most soil types but dramatically decreased phosphatase activity. The responses of the three enzyme activities to warming varied across soil types, which depended on soil properties. In contrast, soil pH was the major driver in regulating urease activity. Soil AN and water content were two key factors for driving phosphatase activity. However, no such relationship was found for sucrase activity. All these responses did not show obvious regional characteristics. Conclusion: These results suggested that soil enzyme was sensitive to air warming, which was associated with different soil properties. Thus, managing soil variables might be a potential strategy to maintain soil enzymatic activity in facing future climate warming. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the recent prevalence and the distributions of morphological subtypes of anaemia in the rural population. Design: Anaemia was defined according to the WHO and the Chinese criteria, and the morphological subtypes of anaemia were classified based on the erythrocyte parameters. The age-standardised prevalence was calculated according to the data of the Population Census 2010 in China. Setting: A cross-sectional study in Henan Province. Participants: 33 585 subjects aged 18–79 years old. Results: The standardised prevalence of anaemia across the WHO and the Chinese definitions was 13·63 % and 5·45 %, respectively. Regardless of which criteria was used, the standardised prevalence of anaemia was higher among women than among men and that increased with age in men, while markedly decreased after menopause in women. There were shifts in morphological patterns of anaemia using the WHO and the Chinese criteria that the standardised prevalence of microcytic anaemia was 3·74 % and 2·97 %, normocytic anaemia was 9·20 % and 2·34 %, and macrocytic anaemia was 0·75 % and 0·14 %, respectively. Besides, there were differences in the influencing factors of anaemia according to different criteria or gender. However, age, education level and renal damage were consistently significantly associated with anaemia in all participants. Conclusions: Anaemia may still be a serious health problem in rural China. It is necessary to reformulate prevention and management strategies to reduce the disease burden of anaemia. [ABSTRACT FROM AUTHOR]

Sufu, a traditional fermented soybean product, is a popular side dish in China and other Asian nations. This paper presents an overview of the relationships between the biogenic amines (BAs) of sufu and its processing and storage conditions. Putrescine and cadaverine were found in almost all sufu products. Thus, a BAs-derived formula is proposed to evaluate sufu quality. The use of selected microorganisms as starters reduces the formation of BAs. While, addition of NaCl and alcohol positively delays the formation of BAs by reducing strain and decarboxylase activities. Similarly, lowering the storage temperature and shortening the storage time are practical measures to control activity of bacteria and of decarboxylases. Industrial sufu products require a long storage time, and thus use of additives, particularly natural ones, represents a viable alternative for the control of BAs. [ABSTRACT FROM AUTHOR]

Drought is showing an increasing trend as a result of the significant variation in precipitation and temperature in China. This study investigated the impacts of drought on ecosystem water use efficiency (WUE) in southwest China. The spatiotemporal distribution of drought and ecosystem WUE were analysed through integrated approaches based on observed climate and satellite remote sensing datasets to understand the response of ecosystem WUE to drought. Also, the impacts of climatic variables on gross primary productivity (GPP), evapotranspiration (ET) and WUE have been discussed. More than 30% of the total area can be categorized as suffering moderate drought. Six drought events (autumn 2006, autumn 2009, winter 2010, summer 2011, autumn 2011 and winter 2013) were identified during the period of 2001–2016. The average monthly WUE was 2.37 gC/kgH2O, showing a decreasing trend under the combined effects of drought and other environmental factors. Autumn 2006 exhibited the highest significant positive effect of drought on WUE on more than 80% of the total area that concentrated in the forest, shrubland, savanna and agriculture ecosystems. The results of this study have implications for ecosystem management and climate policy making that could allow implementing feasible water use strategies under a warming climate. [ABSTRACT FROM AUTHOR]

There are limited literature on the impacts of drought on crop yields in warm regions such as southwest China. Drought vulnerability of four different crops (wheat, rice, maize and sugarcane) cultivated in three provinces (Sichuan, Guizhou and Yunnan) within southwest China were investigated in this study. It was based on the drought index of standardized precipitation evapotranspiration index (SPEI) for ‐3‐ and ‐6 months timescales (SPEI‐3 and SPEI‐6). The correlation between the SPEI and the standardized yield residuals series index for the individual crops was estimated for the period from 1960 to 2018. The highest drought duration was recorded in the southern part of the study area especially in the Yunnan Province. For SPEI‐3, 60% of the total area was affected by drought mainly during the months from August to December for about 13 years (2005–2018). In terms of SPEI‐6, the total affected area by the drought exceeded 80% during the timeframe from 2009 to 2013. Among the studied crops, winter wheat had the highest annual crop yield losses particularly in 2010 when the loss exceeded 50%. The results of this study have implications for agricultural management and climate policymaking in minimizing the influence of drought under the warming climate in southwest China. Further, it provides greater insight into crop–climate interactions and sustainable crop production. [ABSTRACT FROM AUTHOR]

Climate change and human activities have been an important part of studies regarding historical environmental changes in China over the past 2000 years. In this study, we focused on environmental changes, that is, natural disasters and human activities, in the Poyang Lake Basin over the past 2000 years, to analyze interactions between land use cover changes and human activities from the perspective of regional sustainable development. We collected historical records of climate and hydrology, floods and droughts, and rivers and lakes in the Poyang Lake area, and established time sequences for the floods and droughts, lake water level and lake area, amount of farming land, and population, in order to discuss interactions between changes in the environment and the climate, with emphasis on the impacts of extreme events on lake and river basin environment changes. The following results were obtained. First, climate changes in historical periods had wide-ranging and far-reaching impacts on agricultural production, especially disasters caused by climate change. Among the changes in the Poyang Lake basin environment, including river network systems, lake water levels, etc., changes in lake water volume are direct evidence of climate change, adaptation to climate change, and obvious phased characteristics. Second, in the process of changes to the lake and river network in the Poyang Lake Basin, social and economic development is accompanied by evolution of the lake. Increases and decreases in population, the scale of agricultural production, and lake environment changes have direct and significant interactions. Third, the Poyang Lake basin's environmental changes during the historical period are mainly reflected in the pressure feedback mode of "population–agriculture" in the lake environment. [ABSTRACT FROM AUTHOR]

Quantifying the relative influences of anthropogenic activities and climate change on soil erosion and deposition during the Holocene, when both forces have been interacting is a complex problem. Analysis of long-term patterns in soil erosion and lake deposition in a basin can provide the basis for untangling the complexities of climate and anthropogenic forcings. In this paper, sedimentary sequences from Xingyun Lake are compared with simulated soil erosion rates in the basin to explore the relationship between river basin soil erosion and lake deposition during the Holocene in Yunnan, China. Modern soil erosion rates are calculated using RUSLE, while Holocene soil erosion rates are estimated using modern rates with reconstructed precipitation and vegetation cover sequences. Through this investigation, we found the following results. First, Holocene vegetation in the lake basin was mainly affected by climate change, and the vegetation experienced the same pattern of changes as the climate. Soil erosion and lake deposition rates, along with changes to vegetation cover, were synchronous with precipitation trends during the Holocene. Second, soil erosion and lake deposition have been exacerbated by human activities, such as deforestation and land reclamation in the Xingyun Lake basin. Finally, this study provides new insights into the effects by anthropogenic impacts and climate forcing on the processes of soil erosion and lake deposition on the millennium scale. [ABSTRACT FROM AUTHOR]

A potentially important source for soil organic carbon (SOC) in the agricultural ecosystem is straw, straw return has been shown to affect soil bacterial communities. Facing global climate change, the response of bacterial communities to straw return will change at CO2 enrichment. In this study, we investigate the changes of bacterial communities in response to straw return (+straw) at elevated CO2 (eCO2, 700 ppm) in a long-term field experiment of northeast China. Soil samples were taken in the eighth year and analyzed by high throughput sequencing. Soil bacterial communities exhibited distinct clustering according to straw return and eCO2, while eCO2 shortened the distance of clustering between straw return and not. The relative abundances of 10 genera (Acidobacteria_norank, Candidatus_Solibacter, Gaiella, Nocardioides, Streptomyces, C0119_norank, Roseiflexus, Gemmatimonas, Mizugakiibacter and Rhodanobacter) were significantly affected by the interaction of straw × eCO2. In addition, straw return significantly decreased the relative abundances of Gaiellales_norank, Blastococcus, Psedarthrobacter, and Bacillus and increased that of Geminatimonadaceae_norank, Tepidisphaeraceae, Nitrosomonadaceae_norank, and SC-I-84_norank. These differential responses of genera abundances are illustrative of the susceptibility of bacterial communities and indicate their importance in evaluating the fate of exogenous C. The Clusters of Orthologous Groups (COG) analysis showed that straw return had a greater effect on the relative abundances of COG categories than eCO2. The present results point to the need to focus more strongly on the turnover and storage of straw-C during a chronic straw return in the future. [ABSTRACT FROM AUTHOR]

The aim of our study is to quantify the relationship between ecosystem and climate variables in southwest China. We further examined spatiotemporal distribution patterns of daily reference evapotranspiration (ET0) and ecosystem types through integrated approaches, including spatiotemporal interpolation, Penman–Monteith, Mann–Kendall test, statistical correlation analysis and transition matrix based on those datasets including observation climate data, satellite remote sensing images (MODIS and Landsat) and observed ecosystem data. The following results are achieved. First, changes of ET0 were greatly influenced by the combined effects of precipitation (with a decrease rate of −13 mm/10 years) and temperature (with a decrease rate of + 0.17 ℃/10 years). The annual average ET0 increased by + 2.1 mm/10 years, and the increased ET0 are more than 25% of the total area. Second, evapotranspiration was regarded as a sensitive indicator of climate and ecosystem feedbacks, and these ecosystem types have a great transformation, including forest, agriculture, and grass. Forest and grass were distributed primarily in the southern and eastern mountain areas, grass was in high mountains area while agriculture was prevalent in basin areas respond to climate changes. The area of forest converted to grass was 3670 km2, which was greater than transition from grass to forest (1720 km2). Correlation coefficients of evapotranspiration and NDVI were positive in forest and negative in agriculture. Third, the effects of these changes on climate vegetation and ecosystem process feedbacks on the quickly warming southwest China are potentially significant. Although the variation in ecosystem types was combined effects caused by climate variation and human activities, an effective ecological restoration program "Grain for Green" has improved the environmental conditions in southwest China. [ABSTRACT FROM AUTHOR]

• Fire-driven forest mortality in China was greatest during late spring and mid-summer. • Fire-driven forest mortality showed a significant decreasing trend during 2003–2016. • East China, Northeast China and South China had the highest mortality rates in China. Wildfire is one of the most prevalent natural or human-induced disturbances across the world, which can kill trees directly during the active combustion phase or cause delayed forest mortality through interactions with other disturbance agents. With its diverse range of climate and forest ecosystems, China also has diverse forest fire regimes. However, the spatial and temporal patterns of fire-driven forest mortality on the national scale remain largely unexplored. In this study, we employed satellite observations and statistical models to investigate the spatiotemporal patterns and underlying drivers of fire-induced forest mortality across China. Our results demonstrate pronounced temporal patterns of forest burned area and fire-driven forest mortality. On the seasonal scale, forest fires mostly occurred in the winter and spring, whereas the forest mortality is highest from May to July. Both forest burned area and fire-driven mortality exhibited a significant decreasing trend during 2003–2016. Forest burned areas are mainly distributed in Northeast China, Southwest China and South China. There exists a tight spatial consistency between areas with high mortality and burned area with East China as an exception. Correlation analysis and multiple linear regression analysis show that fire size, fire spread rate, fire duration and drought intensity had significant impacts on postfire forest mortality, with fire size and fire spread rate accounting for 38.3% and 37.1%, respectively, of the model's explanatory power. Our results highlight the importance of fire regime impacts on postfire forest mortality. Future climate change that drives more intense fire regimes might thus lead to enhanced forest mortality and increase the loss of forest ecosystem services. [ABSTRACT FROM AUTHOR]

China is committed to achieving carbon neutrality by 2060, which requires that CO 2 emissions from fossil fuels and industrial processes (referred to as CO 2 emissions) be offset by carbon uptake through its terrestrial ecosystems. This study quantified the contributions of China's terrestrial carbon sinks to offsetting CO 2 emissions over 2001–2060 by combining vegetation model simulations and multiple datasets of CO 2 emission projections across different future emission scenarios. Our results showed that China's CO 2 emissions will increase from 0.99 Pg C yr−1 in 2001 to >4 Pg C yr−1 in 2060 under the SSP3–7.0 and SSP5–8.5 scenarios; however, for SSP1–2.6, CO 2 emissions will eventually decrease to 0.50 Pg C yr−1. Conversely, China's net terrestrial carbon sink was projected to increase from −0.14 Pg C yr−1 (2000s) to [−0.35, −0.40] Pg C yr−1 (2050s) under different SSP scenarios based on vegetation modelling. As a result, China's net terrestrial carbon sink will contribute only approximately 10% to offsetting its CO 2 emissions under scenarios SSP3–7.0 and SSP5–8.5, implying an almost certain failure of the carbon-neutral strategy. In contrast, under scenario SSP1–2.6, approximately 50%–80% of CO 2 emissions can be offset by the terrestrial carbon sink by 2060, in line with the possible success of the carbon-neutral goal. This study underscores the critical role of terrestrial carbon sink in achieving carbon neutrality in China and hightlights the remaining challenges for further reducing CO 2 emissions. • China's net terrestrial carbon sink will increase from −0.14 (2000s) to [−0.35, −0.40] Pg C yr−1 (2050s). • China's CO 2 emissions will decrease to 0.50 Pg C by 2060 in SSP1–2.6. • China's net terrestrial carbon sink will offset 50%–80% of CO 2 emissions by 2060 in SSP1–2.6. • It is possible for China to achieve carbon neutrality under the SSP1–2.6 scenario. • China's net terrestrial carbon sink will only offset about 10% of the CO 2 emissions in SSP3–7.0 and SSP5–8.5. [ABSTRACT FROM AUTHOR]

Although straw return, livestock feeding and biochar return are three major effective approaches of straw utilization, the response of soil bacterial communities to the different straw products, especially after long-term addition, remains unclear. Here, we studied the effects of three types of maize-straw products on bacterial community structure in a Mollisol in northeast China. Original maize straw was fed to cattle and pyrolysed to obtain manure and biochar products, respectively. The original straw and manure were separately added to the top 20 cm of soil annually since 2010, but one-time addition for biochar in 2010, and soil samples were collected in the autumn of 2018. The bacterial α diversity and community structure were investigated based on Illumine MiSeq sequencing. The results showed that original straw return only decreased soil bulk density, while manure and biochar return significantly affected soil properties with increased pH, total C, total N and available K compared with control. In addition, manure return increased the concentrations of total and available P compared to control. Straw products did not impact the Ace and Chao indices but changed the Simpson index. Principal coordinate analysis (PCoA) showed that eight-year straw addition shifted the bacterial community structure and exhibited distinct clustering according to straw products. Moreover, distance-based redundancy analysis (db-RDA) revealed that the microbial community structure among soils was significantly associated with bulk density, pH, total C, available P, total K, NO 3 −-N and NH 4 +-N. At the genus level, the abundance of 5 genera decreased and one increased in response to straw return. Manure return induced an increase in the abundance of 2 genera (Mizugakiibacter and Rhizombium) and a decrease in 10 genera. However, the 10 increased and 5 decreased genera with biochar return contributed to the considerable shift of bacterial communities. These results suggested the potential benefits of biochar return in improving bacterial community structure, which might represent a useful strategy for straw utilization. • Bacterial communities exhibited distinct clustering in three straw-product soils. • Much more bacterial genus increased their abundance in biochar return soils. • Biochar return has the greatest potential benefits to manage crop straw. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess the potential association between blood pressure and osteoporosis in a rural population with limited resources. Existing evidence on this association is limited, particularly in such settings., Methods: Data from 7,689 participants in the Henan Rural Cohort study were analyzed. Four blood pressure indicators [systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and pulse pressure (PP)] were measured. The logistic regression model and restricted cubic spline plots were used to assess the relationship between blood pressure indicators and osteoporosis prevalence., Results: Positive trends were noted between blood pressure indicators and osteoporosis prevalence in the entire group and women ( P trend < 0.05 for SBP, MAP, and PP). Women with higher SBP and PP exhibited elevated odds of osteoporosis compared with those with the lowest SBP and PP ( OR s ranging from 1.15 to 1.5 for SBP and 1.06 to 1.83 for PP). No such associations were found in men. These relationships were only evident in postmenopausal women. Dose-response analysis confirmed these findings. Excluding participants taking hypertension medication did not alter the results., Conclusion: In resource-limited settings, higher SBP and PP are associated with the increased prevalence of osteoporosis in women, potentially influenced by menopause-related factors. This indicates that potential gender-based differences and social inequalities may affect bone health., Clinical Trial Registration: The Henan Rural Cohort Study has been registered at the Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699) http://www.chictr.org.cn/showproj.aspx?proj=11375., 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 © 2024 Jin, Zhao, Jin, Yi, Liu, Wang, Zhang and Pan.)

Background: Evidence has suggested the linkage between sleep habits and several metabolic diseases, but the association of sleep factors with bone health remains unclear, especially in regions with low economic levels. Thus, this study aimed to investigate the relationship of nocturnal sleep duration and sleep midpoint with the osteoporosis risk in a rural population., Method: Eligible subjects were derived from the Henan Rural Cohort Study. The Pittsburgh Sleep Quality Index was applied to collect sleep information including sleep initiating time and wake-up time. The bone mineral density of the calcaneus was measured by the ultrasonic bone density apparatus. Multivariable logistic regression models and restricted cubic splines were utilized to evaluate the odds ratio (OR) and 95% confidence intervals (95% CI)., Results: For 8033 participants, 1636 subjects suffered from osteoporosis. Compared with the reference group (7 ~ h group), the ORs and 95% CI of osteoporosis associated with duration of nocturnal sleep were 1.32 (1.10, 1.56), 1.59 (1.25, 2.01), and 1.82 (1.25, 2.65) in the 8 ~ h, 9 ~ h, and ≥ 10 h group, respectively. Additionally, the adjusted ORs and 95% CI were 1.20 (1.01, 1.44) in the early sleep midpoint group and 1.09 (0.92, 1.29) in the intermediate sleep midpoint, compared with the late. Furthermore, there was a joint effect of long duration of nocturnal sleep and the early sleep midpoint on osteoporosis., Conclusion: Long duration of nocturnal sleep and early sleep midpoint were independently and jointly associated with higher risk of osteoporosis in rural areas., Trial Registration: The Henan Rural Cohort Study has been registered at Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699). Date of registration: 06 July 2015. http://www.chictr.org.cn/showproj.aspx?proj=11375., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Evidence linking sleep timing and night sleep duration to dyslipidemia was limited and inconclusive, especially among low- and middle-income adults. The aims were to evaluate the associations between sleep timing, night sleep duration and dyslipidemia in a rural population. Based on the Henan Rural Cohort Study, a total of 37 164 participants were included. The Pittsburgh Sleep Quality Index was used to collect sleep information. Logistic regression and restrictive cubic splines were conducted to explore the associations. Of the 37 164 enrolled participants, 13881 suffered from dyslipidemia. Compared to the reference groups, people who went to sleep after 23:00 or woke up after 7:30 had higher prevalence of dyslipidemia, the adjusted odds ratios ( ORs ) and 95% confidence intervals ( CIs )were 1.30 (1.20-1.41) and 1.34 (1.19-1.50). The adjusted OR (95% CI ) of participants in the Late-sleep/Late-rise category compared to the Early-sleep/Early-rise category was 1.55 (1.08-1.23). Compared to the reference (7~≤8 h), the adjusted OR (95% CI ) was 1.11 (1.03-1.20) for longer (>9 h) night sleep duration. Moreover, the combined effects of sleep duration (>9 h) with sleep time (22:00~) ( OR  = 1.46, 95% CI : 1.16-1.84), sleep duration (>9 h) with wake-up time (≥7:30) ( OR  = 1.28, 95% CI : 1.08-1.51), and sleep duration (>9 h) with the Late-sleep/Late-rise category ( OR  = 1.41, 95% CI : 1.14-1.75) increased the prevalence of dyslipidemia. Accordingly, our results indicate that delayed sleep timing and longer night sleep duration had independent and joint effects on higher risks of dyslipidemia in rural population.

Background: The present study aimed to explore the effect of modification of socioeconomic status (SES) on the association between famine exposure in early life and osteoporosis in adulthood via the baseline data from the Henan Rural cohort study., Methods: A total of 2669 exposed to famine participants were selected from the Henan Rural cohort, and the questionnaires, physical examination and bone mineral density measurement were completed. Specific birth years were used to define five groups: the fetal exposed group, early-childhood exposed group, mid-childhood exposed group, late-childhood exposed group and unexposed group. And the age-matched control group was a combination of the unexposed group and late-childhood exposed group. Multivariable logistic regression models were utilised to analyse the association of famine exposure in early life with osteoporosis in adulthood., Results: The prevalence rates of osteoporosis of participants exposed to famine during the fetal period, early-childhood, mid-childhood and the age-matched group were 21.67%, 25.76%, 23.90% and 18.14%, respectively. The adjusted odds ratios (95% confidence interval) of participants suffering from famine during the fetal period, early-childhood and mid-childhood versus age-matched group were 1.19 (0.82-1.73), 1.40 (1.04-1.88) and 1.57 (1.16-2.13), respectively. The female participants yielded consistent results. The risk of osteoporosis was higher in more severe famine eara. Moreover, an attenuated effect of early life famine exposure on osteoporosis was observed in female participants with high SES., Conclusions: Exposure to famine in early life showed a sex-specific association with an increased risk of osteoporosis in adulthood and the severity of famine may exacerbate this association. In addition, the risk could be modified by SES., (© 2023 British Dietetic Association.)

A potentially important source for soil organic carbon (SOC) in the agricultural ecosystem is straw, straw return has been shown to affect soil bacterial communities. Facing global climate change, the response of bacterial communities to straw return will change at CO 2 enrichment. In this study, we investigate the changes of bacterial communities in response to straw return (+straw) at elevated CO 2 (eCO 2 , 700 ppm) in a long-term field experiment of northeast China. Soil samples were taken in the eighth year and analyzed by high throughput sequencing. Soil bacterial communities exhibited distinct clustering according to straw return and eCO 2 , while eCO 2 shortened the distance of clustering between straw return and not. The relative abundances of 10 genera ( Acidobacteria&#95;norank , Candidatus&#95;Solibacter , Gaiella, Nocardioides , Streptomyces , C0119&#95;norank , Roseiflexus , Gemmatimonas , Mizugakiibacter and Rhodanobacter ) were significantly affected by the interaction of straw × eCO 2 . In addition, straw return significantly decreased the relative abundances of Gaiellales&#95;norank , Blastococcus , Psedarthrobacter , and Bacillus and increased that of Geminatimonadaceae&#95;norank , Tepidisphaeraceae , Nitrosomonadaceae&#95;norank, and SC-I-84&#95;norank . These differential responses of genera abundances are illustrative of the susceptibility of bacterial communities and indicate their importance in evaluating the fate of exogenous C. The Clusters of Orthologous Groups (COG) analysis showed that straw return had a greater effect on the relative abundances of COG categories than eCO 2 . The present results point to the need to focus more strongly on the turnover and storage of straw-C during a chronic straw return in the future.