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Nitrogen addition promotes soil carbon accumulation globally

Science China Life Sciences 2025年第1期68卷 284-293页

作者： Xuemei Yang Suhui Ma Erhan Huang Danhua Zhang Guoping Chen Jiangling Zhu Chengjun Ji Biao Zhu Lingli Liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

关键词： meta-analysis nitrogen enrichment soil organic carbon carbon accumulation carbon stability

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global lessons on delivery of primary healthcare services for people with non-communicable diseases:convergent mixed methods

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Family Medicine and Community health 2024年第3期12卷 13-24页

作者： Robert Mash Lisa R Hirschhorn Inayat Singh Kakar Renu John Manushi Sharma Devarsetty Praveen Stellenbosch University StellenboschSouth Africa Northwestern University ChicagoIllinoisUSA The George Institute for global health New DelhiIndia The George Institute for global health HyderabadIndia Manipal academy of Higher Education ManipalIndia

Objective To extract key lessons on primary healthcare(PHC)service delivery strategies for non-communicable diseases(NCD)from the work of researchers funded by the global Alliance for Chronic Diseases(GACD).Design A convergent mixed methods study that extracted data using a standardised template from research projects funded by the GACD that focused on *** strategies implemented in these studies were mapped onto the PHC Performance Initiative *** qualitative interviews were conducted with researchers from purposefully selected projects to understand the strategies and contextual factors in more *** PHC contexts from low or middle-income countries(LMIC)as well as vulnerable groups within high-income *** came from all regions of the world,particularly East Asia and Pacific,sub-Saharan Africa,South Asia,Latin America and *** The study extracted data on 84 research projects and interviewed researchers from 16 research *** Research projects came from all regions of the world,and mainly focused on diabetes(35.3%),hypertension(28.3%)and mental health(27.6%).Mapped onto the PHC Performance Initiative framework:49.4%focused on high-quality PHC(particularly the comprehensiveness of NCD care,41.2%);41.2%on the availability of PHC services(particularly the competence of healthcare workers,36.5%);35.3%on population health management(particularly community-based services,35.3%);34.1%on facility organisation and management(particularly team-based care,20.0%)and 31.8%on access(particularly digital technology,23.5%).Most common strategies were task shifting and training to improve the comprehensiveness of NCD care through community-based *** factors related to inputs:infrastructure,equipment and medication,workforce(particularly community health workers),finances,health information systems and digital *** Key strategies and contextual factors to improve PHC service del

关键词： services convergent income

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DLSLA 3-D SAR imaging algorithm for off-grid targets based on pseudo-polar formatting and atomic norm minimization

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Science China(Information Sciences) 2016年第6期59卷 225-239页

作者： Qian BAO Kuoye HAN Xueming PENG Wen HONG Bingchen ZHANG Weixian TAN Science and Technology on Microwave Imaging Laboratory (MITL) Institute of ElectronicsChinese Academy of Sciences (IECAS) School of Electronic and Communication Engineering University of Chinese Academy of Sciences (UCAS) Information System Technology Institute Information Science Academy of China Electronics Technology Group Corporation global RD Centre (Shanghai) Carestream Health Incorporated College of Information Engineering Inner Mongolia University of Technology

This paper concerns the imaging problem for downward looking sparse linear array three-dimensional synthetic aperture radar(DLSLA 3-D SAR) under the circumstance of sparse and non-uniform cross-track dimensional virtual phase centers configuration. Since the 3-D imaging scene behaves typical sparsity in a certain domain, sparse recovery approaches hold the potential to achieve a better reconstruction performance. However,most of the existing compressive sensing(CS) algorithms assume the scatterers located on the pre-discretized grids, which is often violated by the off-grid effect. By contrast, atomic norm minimization(ANM) deals with sparse recovery problem directly on continuous space instead of discrete grids. This paper firstly analyzes the off-grid effect in DLSLA 3-D SAR sparse image reconstruction, and then introduces an imaging method applied to off-gird targets reconstruction which combines 3-D pseudo-polar formatting algorithm(pseudo-PFA) with ANM. With the proposed method, wave propagation and along-track image reconstruction are operated with pseudo-PFA, then the cross-track reconstruction is implemented with semidefinite programming(SDP) based on the ANM model. The proposed method holds the advantage of avoiding the off-grid effect and managing to locate the off-grid targets to accurate locations in different imaging scenes. The performance of the proposed method is verified and evaluated by the 3-D image reconstruction of different scenes, i.e., point targets and distributed scene.

关键词： atomic norm minimization DLSLA 3-D SAR sparse recovery off-grid targets pseudo-PFA 3-D imaging

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Prevalence of Atrial Fibrillation in China and Its Risk Factors

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Biomedical and Environmental Sciences 2013年第9期26卷 709-716页

作者： LI Ying WU Yang Feng CHEN Ke Ping LI Xian ZHANG Xing XIE Gao Qiang WANG Fang Zheng ZHANG Shu State Key Laboratory of Cardiovascular Disease Fuwai Hospital National Center for Cardiovascular Disease Chinese Academy of Medical Sciences and Peking Union Medical College Peking University Clinical Research Institute The George Institute for global health at Peking University health Science Center

Objective To study the prevalence of atrial fibrillation （AF） and the relation with its risk factors in China. Methods A total of 19 363 participants （8635 males and 10 728 females） aged 〉35 years in geographically dispersed urban and rural regions of China were included in this cross-sectional survey. All participants received questionnaire, physical and blood examination. Echocardiography were performed for AF patients found in the survey. Results Of the 19 363 participants, 199 were diagnosed with AF. The estimated age-standardized prevalence of AF was 0.78% in men and 0.76% in women. The prevalence of AF in participants aged 〈60 years was 0.41% in men and 0.43% in women, and was 1.83% in both men and women aged 〉_60 years. About 19.0% of males and 30.9% of females with AF were diagnosed with valve disease. Age- and sex-adjusted multivariable logistic regression analysis revealed that myocardial infarction, left ventricular hypertrophy （LVH）, obesity, and alcohol consumption were associated with a increased risk of AF（P〈0.05）. Conclusion The age standardized prevalence of AF is 0.77% in the participants enrolled in the present study. The number of AF cases aged 〉35 years is 5.26 million according to 2010 Chinese Census. Most risk factors for AF, identified mainly in Western countries, are also detected in China.

关键词： Atrial fibrillation Epidemiology Risk factors Chinese population

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Confronting COVID-19 and Prioritizing Aging Population

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China CDC weekly 2023年第10期5卷 229-233页

作者： Binbin Su Yannan Luo Yaohua Tian Chen Chen Xiaoying Zheng School of Population Medicine and Public health Chinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina Department of global health School of Public HealthPeking UniversityBeijingChina Ministry of Education Key Laboratory of Environment and health and State Key Laboratory of Environmental Health(Incubating)School of Public HealthTongji Medical CollegeWuhan CityHubei ProvinceChina

Over the past three years,China has implemented rapid,vigorous,and coordinated control measures to limit the spread of coronavirus disease 2019(COVID-19)*** measures include active containment,graded management,rational resource allocation,rapid contact tracing and disposal,and targeted vaccination of key *** efforts have contributed to the prompt and effective control of outbreaks,protecting the health and well-being of older *** review provides a comprehensive summary of the changes in China’s COVID-19 prevention and control experiences and other public health measures since the outbreak of the pandemic,and assesses their impact on older *** may serve as a valuable reference for future epidemic prevention and control efforts.

关键词： prevention measures prompt

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Monitoring air pollution in China from geostationary satellite： A synthetic study using simulated observations

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Science China Earth Sciences 2018年第11期61卷 1622-1632页

作者： Xi CHEN Zhaonan CAI Yi LIU Dongxu YANG Key Laboratory of Middle Atmosphere and global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100079 China University of Chinese academy of Sciences Beijing 100049 China

We simulated geostationary satellite observations to assess the potential for high spatial-and temporal-resolution monitoring of air pollution in China with a focus on tropospheric ozone(O_3), nitrogen dioxide(NO_2), sulfur dioxide(SO_2), and formaldehyde(HCHO). Based on the capabilities and parameters of the payloads onboard sun-synchronous satellites, we simulated the observed spectrum based on a radiative transfer model using a geostationary satellite model. According to optimal estimation theory, we analyzed the sensitivities and retrieval uncertainties of the main parameters of the instrument for the target trace gases. Considering the retrieval error requirements of each trace gas, we determined the major instrument parameter values(e.g., observation channel, spectral resolution, and signal-to-noise ratio). To evaluate these values, retrieval simulation was performed based on the three-dimensional distribution of the atmospheric components over China using an atmospheric chemical transportation model. As many as 90% of the experiments met the retrieval requirements for all target gases. The retrieval precision of total-column and stratospheric O_3 was 2%. In addition, effective retrieval of all trace gases could be achieved at solar zenith angles larger than 70°. Therefore, the geostationary satellite observation and instrument parameters provided herein can be used in air pollution monitoring in China. This study offers a theoretical basis and simulation tool for improving the design of instruments onboard geostationary satellites.

关键词： Air pollution Geostationary satellite Instrument parameters Retrieval error

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Progresses in the Atmospheric Electricity Researches in China during 2006-2010

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Advances in Atmospheric Sciences 2012年第5期29卷 993-1005页

作者：郄秀书 Key Laboratory of Middle Atmosphere and global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences

Atmospheric electricity is composed of a wide range of electric phenomena in the troposphere, strato- sphere, and even lower ionosphere. Research progress on atmospheric electricity in the past 5 years in China are briefly reviewed here. This research area has been greatly expanded through rocket-triggered lightning experiments and the increased use of high spatio-temporal resolution techniques for the detection and location of lightning. The main results described in this review are summarized in the following five aspects：（1） processes and parameters inferred from rocket-triggered lightning, （2） lightning physics and ef- fects （observations and theoretical study）, （3） lightning activities associated with different thunderstorms, （4） charge structure of thunderstorms （observations and simulation）, and （5） the VHF/UHF lightning location techniques and discharge channel mapping.

关键词： lightning physics thunderstorm electricity lightning meteorology lightning climatology light- ning effects

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A Parameterized yet Accurate Model of Ozone and Water Vapor Transmittance in the Solar-to-near-infrared Spectrum

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Advances in Atmospheric Sciences 2012年第3期29卷 599-610页

作者：刘为一邱金恒 Key Laboratory of Middle Atmosphere and global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences

A parameterized transmittance model （PTR） for ozone and water vapor monochromatic transmittance calculation in the solar-to-near-infrared spectrum 0.3-4 pm with a spectral resolution of 5 cm-1 was developed based on the transmittance data calculated by Moderate-resolution Transmittance model （MOD- TRAN）. Polynomial equations were derived to represent the transmittance as functions of path length and airmass for every wavelength based on the least-squares method. Comparisons between the transmittances calculated using PTR and MODTRAN were made, using the results of MODTRAN as a reference. Rela- tive root-mean-square error （RMSre） was 0.823% for ozone transmittance. RMSre values were 8.84~ and 3.48~ for water vapor transmittance ranges of 1-1 x 10-is and 1-1x 10-3, respectively. In addition, the Stratospheric Aerosol and Gas Experiment II （SAGEII） ozone profiles and University of Wyoming （UWYO） water vapor profiles were applied to validate the applicability of PTR model. RMSre was 0.437~ for ozone transmittance. RMSre values were 8.89~ and 2.43% for water vapor transmittance ranges of 1-1~10-is and 1-1~ 10-6, respectively. Furthermore, the optical depth profiles calculated using the PTR model were compared to the results of MODTRAN. Absolute RMS errors （RMSab） for ozone optical depths were within 0.0055 and 0.0523 for water vapor at all of the tested altitudes. Finally, the comparison between the solar heating rate calculated from the transmittance of PTR and Line-by-Line radiative transfer model （LBLRTM） was performed, showing a maximum deviation of 0.238 K d-1 （6% of the corresponding solar heating rate calculated using LBLRTM）. In the troposphere all of the deviations were within 0.08 K d-1. The computational speed of PTR model is nearly two orders of magnitude faster than that of MODTRAN.

关键词： parameterization transmittance atmospheric absorption

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Analysis of XCO_2 retrieval sensitivity using simulated Chinese Carbon Satellite(TanSat) measurements

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Science China Earth Sciences 2014年第8期57卷 1919-1928页

作者： CAI ZhaoNan LIU Yi YANG DongXu Key Laboratory of Middle Atmosphere and global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences

We present a study on the retrieval sensitivity of the column-averaged dry-air mole fraction of CO2(XCO2) for the Chinese carbon dioxide observation satellite(TanSat) with a full physical forward model and the optimal estimation technique. The forward model is based on the vector linearized discrete ordinate radiative transfer model(VLIDORT) and considers surface reflectance, gas absorption, and the scattering of air molecules, aerosol particles, and cloud particles. XCO2 retrieval errors from synthetic TanSat measurements show solar zenith angle(SZA), albedo dependence with values varying from 0.3 to 1 ppm for bright land surface in nadir mode and 2 to 8 ppm for dark surfaces like snow. The use of glint mode over dark oceans significantly improves the CO2 information retrieved. The aerosol type and profile are more important than the aerosol optical depth, and underestimation of aerosol plume height will introduce a bias of 1.5 ppm in XCO2. The systematic errors due to radiometric calibration are also estimated using a forward model simulation approach.

关键词： TanSat retrieval sensitivity retrieval error simulation XCO2

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Intraseasonal Oscillation of Tropospheric Ozone over the Indian Summer Monsoon Region

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Advances in Atmospheric Sciences 2019年第4期36卷 417-430页

作者： Yuli ZHANG Chuanxi LIU Yi LIU Rui YANG Key Laboratory of Middle Atmosphere and global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences

Boreal summer intraseasonal oscillation(BSISO) of lower tropospheric ozone is observed in the Indian summer monsoon(ISM) region on the basis of ERA-Interim reanalysis data and ozonesonde data from the World Ozone and Ultraviolet Radiation Data Centre. The 30–60-day intraseasonal variation of lower-tropospheric ozone shows a northwest–southeast pattern with northeastward propagation in the ISM region. The most significant ozone variations are observed in the Maritime Continent and western North Pacific. In the tropics, ozone anomalies extend from the surface to 300 hPa; however, in extratropical areas, it is mainly observed under 500 hPa. Precipitation caused by BSISO plays a dominant role in modulating the BSISO of lower-tropospheric ozone in the tropics, causing negative/positive ozone anomalies in phases 1–3/5–6. As the BSISO propagates northeastward to the western North Pacific, horizontal transport becomes relatively more important, increasing/reducing tropospheric ozone via anticyclonic/cyclonic anomalies over the western North Pacific in phases 3–4/7–*** two extreme conditions of the ISM, most of its active/break events occur in BSISO phases 4–7/1–8 when suppressed/enhanced convection appears over the equatorial eastern Indian Ocean and enhanced/suppressed convection appears over India, the Bay of Bengal, and the South China Sea. As a result, the BSISO of tropospheric ozone shows significant positive/negative anomalies over the Maritime Continent, as well as negative/positive anomalies over India, the Bay of Bengal,and the South China Sea in active/break spells of the ISM. This BSISO of tropospheric ozone is more remarkable in break spells than in active spells of the ISM, due to the stronger amplitude of BSISO in the former.

关键词： boreal summer intraseasonal oscillation tropospheric ozone Indian summer monsoon active/break spell

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