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合理确定排涝泵站规模的感潮河道模型试验研究

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长江科学院院报 2024年第4期41卷 23-28页

作者：刘中峰黄本胜刘达李明广东省水利水电科学研究院广州510635 广东省水动力学应用研究重点实验室广州510635 河口水利技术国家地方联合工程实验室广州510635 广东省水安全科技协同创新中心广州510635

合理确定泵站规模一直是感潮河道排涝工程设计中的关键问题。通过建立物理模型,在选定的水文边界条件和相应工程运行要求下,对某感潮水系两座涌口泵站规模进行试验研究。试验发现,受限于河涌过流能力,泵站规模存在临界值,超过该值后,即... 详细信息

合理确定泵站规模一直是感潮河道排涝工程设计中的关键问题。通过建立物理模型,在选定的水文边界条件和相应工程运行要求下,对某感潮水系两座涌口泵站规模进行试验研究。试验发现,受限于河涌过流能力,泵站规模存在临界值,超过该值后,即使再进一步增加泵站规模,水位也不会继续下降;泵站抽排对某位置水位的降低效应与泵站和该位置之间的距离密切相关,距离越近,水位降低越明显。基于上述认识,通过试验确定了满足水位管控要求的两座泵站规模的合理组合:距离相对较远的温涌泵站为80 m3/s,较近的金紫涌泵站为130 m~3/s。试验方法和主要成果可为工程方案比选及优化提供重要依据,对类似河涌整治工程也具有一定的借鉴意义。

关键词：感潮河道排涝泵站规模物理模型试验水位整治工程

The ALMA-QUARKS Survey.Ⅰ.Survey Description and Data Reduction

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Research in Astronomy and Astrophysics 2024年第2期24卷 104-124页

作者：刘训川 Tie liu Lei Zhu Guido Garay Hong-li liu Paul Goldsmith Neal Evans Kee-Tae Kim sheng-Yuan liu Fengwei Xu Xing Lu Anandmayee Tej Xiaofeng Mai Leonardo Bronfman Shanghuo li Diego Mardones Amelia Stutz Ken'ichi Tatematsu Ke Wang Qizhou Zhang sheng-li Qin Jianwen zhou Qiuyi Luo Siju Zhang Yu Cheng Jinhua He Qilao Gu Ziyang li Zhenying Zhang Suinan Zhang Anindya Saha Lokesh Dewangan Patricio Sanhueza Zhiqiang Shen Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Departamento de Astronomía Universidad de ChileLas Condes7591245 SantiagoChile School of Physics and Astronomy Yunnan UniversityKunming 650091China Jet Propulsion Laboratory California Institute of Technology4800 Oak Grove DrivePasadena CA 91109USA Department of Astronomy The University of Texas at AustinTX 78712-1205USA Korea Astronomy and Space Science Institute 776 Daedeokdae-roYuseong-guDaejeon 34055Republic of Korea Institute of Astronomy and Astrophysics Academia SinicaRoosevelt RoadTaipei 10617China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Indian Institute of Space Science and Technology Thiruvananthapuram 695547KeralaIndia Max Planck Institute for Astronomy Königstuhl 17D-69117 HeidelbergGermany Departamento de Astronomía Universidad de ConcepciónCasilla 160-CConcepciónChile Nobeyama Radio Observatory National Astronomical Observatory of JapanNational Institutes of Natural Sciences462-2 NobeyamaMinamimakiMinamisakuNagano 384-1305Japan Center for Astrophysics∣Harvard&Smithsonian 60 Garden StreetCambridgeMA 02138USA Max-Planck-Institut für Radioastronomie Auf dem Hügel 69D-53125 BonnGermany School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China National Astronomical Observatory of Japan 2-21-1 OsawaMitakaTokyo181-8588Japan Yunnan Observatories Chinese Academy of SciencesKunming 650216China Physical Research Laboratory NavrangpuraAhmedabad-380009India Astronomical Science Program The Graduate University for Advanced StudiesSOKENDAI2-21-1 OsawaMitakaTokyo 181-8588Japan University of Science and Technology Korea(UST)217 Gajeong-roYuseong-guDaejeon 34113Republic o

This paper presents an overview of the QUARKS survey,which stands for Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures."The QUARKS survey is observing139 massive clumps covered by 156 pointings at Atacama Large Millimeter/submillimeter Array(ALMA)Band 6(λ~1.3 mm).In conjunction with data obtained from the ALMA-ATOMS survey at Band 3(λ~3 mm),QUARKS aims to carry out an unbiased statistical investigation of massive star formation process within protoclusters down to a scale of 1000 *** overview paper describes the observations and data reduction of the QUARKS survey,and gives a first look at an exemplar source,the mini-starburst Sgr B2(M).The wide-b and width(7.5 GHz)and high-angular-resolution(~0."3)observations of the QUARKS survey allow for the resolution of much more compact cores than those could be done by the ATOMS survey,and to detect previously unrevealed fainter filamentary *** spectral windows cover transitions of species including CO,SO,N_(2)D^(+),SiO,H_(30)α,H_(2)CO,CH_(3)CN,and many other complex organic molecules,tracing gas components with different temperatures and spatial *** aims to deepen our understanding of several scientific topics of massive star formation,such as the mass transport within protoclusters by(hub-)filamentary structures,the existence of massive starless cores,the physical and chemical properties of dense cores within protoclusters,and the feedback from already formed high-mass young protostars.

关键词： stars formation-stars kinematics and dynamics-ISM clouds-ISM molecules

Increase of PCSK9 expression in diabetes promotes VEGFR2ubiquitination to inhibit endothelial function and skin wound healing

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Science China life Sciences 2024年

作者： Jian-Jun Gao Fang-Yuan Wu Yu-Jia liu Le li Yi-Jun lin Yue-Ting Kang Yue-ming Peng Yi-Fang liu Chen Wang Zhen-sheng Ma Yang Cao Hong-Yu Cao Zhi-Wei Mo Yan li Jing-Song Ou Zhi-Jun Ou Division of Cardiac Surgery Cardiovascular Diseases Institute The First Affiliated Hospital Sun Yat-sen University National-Guangdong Joint Engineering Laboratory for Diagnosis and Treatment of Vascular Diseases NHC key Laboratory of Assisted Circulation and Vascular Diseases (Sun Yat-sen University) Key Laboratory of Assisted Circulation and Vascular Diseases Chinese Academy of Medical Sciences Guangdong Provincial Engineering and Technology Center for Diagnosis and Treatment of Vascular Diseases Division of Hypertension and Vascular Diseases Department of Cardiology Heart Center The First Affiliated Hospital Sun Yat-sen University Division of Vascular Surgery The First Affiliated Hospital Sun Yat-sen University Guangdong Provincial Key Laboratory of Brain Function and Disease Zhongshan School of Medicine Sun Yat-sen University

Diabetic foot ulcers（DFUs） are a serious vascular disease. Currently, no effective methods are available for treating DFUs. Pro-protein convertase subtilisin/kexin type 9（PCSK9） regulates lipid levels to promote atherosclerosis. However, the role of PCSK9 in DFUs remains unclear. In this study, we found that the expression of PCSK9 in endothelial cells（ECs） increased significantly under high glucose（HG）stimulation and in diabetic plasma and vessels. Specifically, PCSK9 promotes the E3 ubiquitin-protein ligase NEDD4 binding to vascular endothelial growth factor receptor 2（VEGFR2）, which led to the ubiquitination of VEGFR2, resulting in its degradation and downregulation in ECs. Furthermore, PCSK9 suppresses the expression and activation of AKT, endothelial nitric oxide synthase（eNOS）, and ERK1/2, leading to decreased nitric oxide（NO） production and increased superoxide anion(O2·-) generation, which impairs vascular endothelial function and angiogenesis. Importantly, using evolocumab to limit the increase in PCSK9 expression blocked the HG-induced inhibition of NO production and the increase in O2·-production, as well as inhibited the phosphorylation and expression of AKT, eNOS, and ERK1/***, evolocumab improved vascular endothelial function and angiogenesis, and promoted wound healing in diabetes. Our findings suggest that targeting PCSK9 is a novel therapeutic approach for treating DFUs.

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Bird species composition and conservation challenges in the Gaoligong Mountains, one of the most diverse bird areas in the world

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Zoological Research(Diversity and Conservation) 2024年第1期1卷 20-50页

作者： Fei Wu Jian-Yun Gao Dao Yan Le Yang Lu-ming liu Shun-Yu Yao Chang-sheng Zuo Jun Sun Ge Gao Jian-Yong Su li Luo Ying-Chun li ming liu Yuan-Fang Hu ming Wei Xiao-Jun Yang State Key Laboratory of Genetic Resources and Evolution&Yunnan Key Laboratory of Biodiversity and Ecological Conservation of Gaoligong Mountain Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650201China Xizang Plateau Institute of Biology LhasaXizang 850001China Kunming Natural History Museum of Zoology Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Yunnan Tongbiguan Provincial Nature Reserve DehongYunnan 679300China Yunnan Gaoligongshan National Nature Reserve NujiangYunnan 671400China Yunnan Gaoligongshan National Nature Reserve BaoshanYunnan 678000China China Birdwatching Association KunmingYunnan 650225China Gaoligong Mountain Forest Ecosystem Observation and Research Station of Yunnan Province Dulongjiang Forest Ecosystem Research StationGongshanYunnan 673500China

The Gaoligong Mountains(GLGM),located in southwestern China,extend north to south along the western border of the Hengduan Mountains,spanning approximately 600 *** this study,we consolidated findings from 17 bird surveys conducted in the GLGM between 2010 and *** found that the GLGM harbors tremendous bird diversity,with a total of 796 documented bird species in the *** a quarter(23.0%)of these species are listed as state key protected species or as Chinese and global threatened *** of species richness at the county level showed a decreasing trend with increasing latitude,with the greatest diversity in Yingjiang(661 species).Observations indicated that the GLGM belongs to the Oriental realm,primarily composed of bird species from southern and southwestern *** GLGM plays an important role in avian conservation by sheltering exceptional bird diversity,providing corridors and flyways for bird migration and dispersal,and mitigating the effects of climate *** response to the conservation needs of birds and other wildlife,the Chinese government has established numerous protected areas within the *** these efforts,avian conservation still faces considerable challenges in the GLGM due to limitations in the protected area network,transboundary nature of the regions,and existing gaps in monitoring and research.

关键词： Birds Gaoligong Mountains Zoogeographic region Conservation challenge

A polarization sensitive interferometer:Delta interferometer

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Chinese Physics B 2024年第3期33卷 369-377页

作者：卫超奇刘建彬董翼飞孙雨农周宇郑淮斌刘严严闫秀生李福利徐卓 Key Laboratory of Multifunctional Materials and Structures Ministry of Education & International Center for Dielectric ResearchSchool of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an 710049China MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Department of Applied PhysicsXi'an Jiaotong UniversityXi'an 710049China Science and Technology on Electro-Optical Information Security Control Laboratory Tianjin 300308China

A new type of polarization sensitive interferometer is proposed,named the Delta interferometer,inspired by its geometry resembling the Greek letter *** main difference between the Delta interferometer and other existing interferometers,such as Michelson,Mach-Zehnder and Young's double-slit interferometers,is that the two interfering paths are asymmetrical in the Delta *** visibility of the first-order interference pattern observed in the Delta interferometer is dependent on the polarization of the incidental *** coherence theory is employed to interpret this phenomenon and single-mode continuous-wave laser light is employed to verify the theoretical *** theoretical and experimental results are *** Delta interferometer is a perfect tool to study the reflection of electromagnetic fields in different polarizations and may find applications in polarization-sensitive scenarios.

关键词： phase sensitive interferometer Fresnel formula first-order interference

Probing dark matter particles from evaporating primordial black holes via electron scattering in the CDEX-10 experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 87-95页

作者： Zhenhua Zhang litao Yang Qian Yue Kejun Kang Yuanjing li Haipeng An Greeshma C. Jianping Chang Yunhua Chen Jianping Cheng Wenhan Dai Zhi Deng Changhao Fang Xinping Geng Hui Gong Qiuju Guo Tao Guo Xuyuan Guo li He shengming He Jinwei Hu Hanxiong Huang Tuchen Huang lin Jiang S.Karmakar Haubin li Hanyu li Jianmin li Jin li Qianyun li Renmingjie li Xueqian li Yulan li Yifan liang Bin liao FongKay lin ShinTed lin Jiaxuan liu Shukui liu Yandong liu Yu liu Yuanyuan liu Hao Ma Yucai Mao Qiyuan Nie Jinhua Ning Hui Pan Ningchun Qi Jie Ren Xichao Ruan Monoj Kumar Singh Tianxi Sun Changjian Tang Yang Tian Guangfu Wang Junzheng Wang li Wang Qing Wang Yufeng Wang Yunxiang Wang Henry Tsz-King Wong Shiyong Wu Yucheng Wu Haoyang Xing Rui Xu Yin Xu Tao Xue Yulu Yan Nan Yi Chunxu Yu Haijun Yu Jianfeng Yue ming Zeng Zhi Zeng Bingtao Zhang Fengshou Zhang Lei Zhang Zhenyu Zhang Jizhong Zhao Kangkang Zhao minggang Zhao Jifang zhou Zuying zhou Jingjun Zhu CDEX Collaboration Key Laboratory of Particle and Radiation Imaging (Ministry of Education) and Department of Engineering Physics Tsinghua University Department of Physics Tsinghua University Institute of Physics Academia Sinica NUCTECH Company YaLong River Hydropower Development Company College of Nuclear Science and Technology Beijing Normal University College of Physics Sichuan University School of Physics Peking University Department of Nuclear Physics China Institute of Atomic Energy Sino-French Institute of Nuclear and Technology Sun Yet-sen University School of Physics Nankai University Department of Physics Banaras Hindu University Department of Physics Beijing Normal University

Dark matter（DM） is a major constituent of the ***,no definite evidence of DM particles（denoted as “χ”） has been found in DM direct detection（DD） experiments to *** is a novel concept of detectingχfrom evaporating primordial black holes（PBHs）.We search forχemitted from PBHs by investigating their interaction with target *** examined PBH masses range from 1×1015to 7×1016g under the current limits of PBH abundance *** 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude the χ-electron（χ-e） elastic-scattering cross section σχe～5×10-29cm2for χ with a mass ■ keV from our *** the higher radiation background but lower energy threshold（160 eV）,CDEX-10 fills a part of the gap in the previous *** (mχ,σχe) can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.

关键词： CDEX primordial black hole light dark matter particle dark matter-electron scattering high purity germanium detector

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The real-world study of the clinical characteristics,diagnosis,and treatment of advanced pancreatic cancer in China

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Journal of Pancreatology 2024年第1期7卷 1-9页

作者： Jiujie Cui Qihan Fu Xiaobing Chen Yanling Wang Qi li Feng Wang Zhihua li Guanghai Dai Yusheng Wang Hongmei Zhang Houjie liang Jun zhou liu Yang Fenghua Wang Leizhen Zheng Xiaofeng Chen Ping Gong Jiang liu Ying Yuan lin Wang Yuejuan Cheng Jun Zhang Yuhong zhou Weijian Guo Xianbao Zhan Zhengyun Zou Da li Shan Zeng Enxiao li Zhiwei li Zan Teng Dan Cao Jie Kan Jianping Xiong ming Quan Jiayu Yao Haiyan Yang liwei Wang Department of Medical Oncology Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Medical Oncology The First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhouChina Department of Medical Oncology Affiliated Cancer Hospital of Zhengzhou UniversityHenan Cancer HospitalZhengzhouChina Department of Medical Oncology Shanghai General HospitalShanghai Jiao Tong UniversityShanghaiChina Department of Medical Oncology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina Department of Medical Oncology Sun Yat-sen Medical Hospital Sun Yat-sen UniversityGuangzhouChina Medical Oncology Chinese PLA General HospitalBeijingChina Department of Gastrointestinal Oncology Shanxi Provincial Cancer HospitalAffiliated to Shanxi Medical UniversityTaiyuanChina Department of Clinical Oncology Xijing HospitalAir Force Medical UniversityXi’anChina Department of Oncology and Southwest Cancer Center Southwest HospitalThird Military Medical University(Army Military Medical University)ChongqingChina Department of Gastrointestinal Oncology Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing)Peking University Cancer Hospital&InstituteBeijingChina Cancer Center Department of Medical OncologyZhejiang Provincial People’s HospitalPeople’s Hospital of Hangzhou Medical CollegeHangzhouChina Department of Medical Oncology Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdongChina Oncology Department Xin Hua Hospital Affiliated to Shanghai JiaoTong University School of MedicineShanghaiChina Department of Oncology the First Affiliated Hospital with Nanjing Medical UniversityNanjingChina Department of Oncology The First Affiliated HospitalSchool of MedicineShihezi UniversityShiheziChina Department of Oncology People’s Hospital of Xinjiang Uygur Autonomous RegionXinjiangChina Department of Medical Oncology t

Objective:Real-world diagnostic and treatment data for pancreatic cancer in China are *** such,the present study investigated the clinical characteristics,diagnosis,and treatment of advanced pancreatic cancer(including locally advanced and metastatic disease)in the Hospital-based Advanced Pancreatic Cancer Cohort in China of the China Pancreas Data Center ***:A total of 5349 Chinese patients with advanced pancreatic cancer were identified from a *** entire course of real-world pancreatic cancer management was ***:The proportion of patients with advanced pancreatic cancer was higher among males than females(62.4%vs 37.6%,respectively).Patients typically had a history of hypertension(30.8%),diabetes(21.6%),and cholangitis(20.2%).Abdominal pain(51.6%),abdominal distension(27.1%),jaundice(20.1%),and weight loss(16.3%)were the main symptoms observed in patients with advanced pancreatic cancer in this *** carbohydrate antigen(CA)19-9 is one of the most common tumor *** the present study,2562 patients underwent first-line *** median progression-free survival(PFS)for patients undergoing first-line therapy was 4.1 *** major options for first-line therapy included gemcitabine(GEM)plus S-1(GS/X)(23.4%),nab-paclitaxel plus GEM(AG)(18.1%),oxaliplatin,irinotecan,and leucovorin-modulated fluorouracil(FOLFIRINOX;11.9%),nab-paclitaxel plus S-1(AS)(8.9%),and GEM combined with oxaliplatin/cisplatin(GEMOX/GP)(7.6%).The AS and GS/X regimens were associated with the highest PFS ***:This is the first study to report multicenter,real-world data regarding advanced pancreatic cancer in *** revealed that real-world treatment options differed from guideline recommendations,and PFS was shorter than that in previously reported *** intelligent follow-up systems and standardizing diagnosis and treatment of pancreatic cancer is recommended.

关键词： Advanced pancreatic cancer China Pancreas Data Center Chinese First-line regimens Real-world study

Diagnosis,treatment and prevention of severe acute respiratory syndrome coronavirus 2 infection in children:experts'consensus statement updatedforthe Omicron variant

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World Journal of Pediatrics 2024年第3期20卷 272-286页

作者： Rong-Meng Jiang Zheng-De Xie Yi Jiang Xiao-Xia Lu Run-ming Jin Yue-Jie Zheng Yun-Xiao Shang Bao-Ping Xu Zhi-sheng liu Gen Lu Ji-Kui Deng Guang-Hua liu Xiao-Chuan Wang Jian-She Wang Lu-Zhao Feng Wei liu Yi Zheng Sai-Nan Shu Min Lu Wan-Jun Luo Miao liu Yu-Xia Cui Le-Ping Ye A-Dong Shen Gang liu li-Wei Gao li-Juan Xiong Yan Bai li-Kai lin Zhuang Wei Feng-Xia Xue Tian-You Wang Dong-Chi Zhao Jian-Bo Shao Daniel Kwok-keung Ng Gary Wing-kin Wong Zheng-Yan Zhao Xing-Wang li Yong-Hong Yang Kun-ling Shen Diagnosis and Treatment Center of Infectious Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Beijing Key Laboratory of Pediatric Respiratory Infection Diseases Key Laboratory of Major Diseases in ChildrenMinistry of EducationNational Clinical Research Center for Respiratory DiseasesResearch Unit of Critical Infection in ChildrenChinese Academy of Medical Sciences2019RU016Laboratory of Infection and VirologyBeijing Pediatric Research InstituteBeijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China Department of Pediatrics Renmin Hospital of Wuhan UniversityWuhan 430060China Department of Respiratory Wuhan Children's HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Department of Pediatrics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Respiratory Shenzhen Children's HospitalShenzhen 518038China Department of Pediatric Respiratory Shengjing Hospital Affiliated to China Medical UniversityShenyang 110004China Department of Respiratory Beijing Children's HospitalCapital Medical UniversityNational Clinical Research Center for Respiratory DiseasesNational Center for Children's HealthBeijing 100045China Department of Neurology Wuhan Children's HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Department of Respiratory Guangzhou Women and Children's Medical CenterGuangzhou 510623China Department of Infectious Diseases Shenzhen Children's HospitalShenzhen 518038China Department of Pediatrics Fujian Branch of Shanghai Children's Medical CenterFujian Children's HospitalFuzhou350005China Department of Clinical Immunology and Allergy Children's Hospital of Fudan UniversityNational Center for Children's HealthShanghai 201102China Department of Infectious Diseases Children's Hospital of Fudan UniversityNational Center for Children's Health.Shanghai

It has been more than 3 years since the novel coronavirus(SARS-CoV-2)pandemic raged *** coronavirus disease 2019(COVID-19)has greatly influenced human *** to data from the World Health Organization(WHO),there were ove... 详细信息

关键词： prevention infection statement

紫色土丘陵区退耕还林对坡地土壤碳氮空间分布的影响

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环境科学 2024年第7期45卷 4206-4217页

作者：李子阳刘伟李春培朱波周明华中国科学院水利部成都山地灾害与环境研究所山地表生过程与生态调控重点实验室成都610041 中国科学院大学北京100049 四川省泸州市叙永县农业农村局泸州646400

为了弥补我国四川盆地紫色土丘陵区退耕还林对坡地土壤碳(C)和氮(N)时空分布影响的研究不足,依托中国科学院盐亭紫色土农业生态试验站在万安小流域建立的长期观测样地,对比分析了约30年历史的退耕林地及其邻近的坡耕地不同坡面位置土壤... 详细信息

为了弥补我国四川盆地紫色土丘陵区退耕还林对坡地土壤碳(C)和氮(N)时空分布影响的研究不足,依托中国科学院盐亭紫色土农业生态试验站在万安小流域建立的长期观测样地,对比分析了约30年历史的退耕林地及其邻近的坡耕地不同坡面位置土壤的C、N形态、含量及其储量.结果发现,退耕还林后,显著增加了剖面土壤有机碳(SOC)含量及储量(P0.05).此外,研究还发现空间位置对坡耕地土壤TN、SOC、NO_(3)^(−)-N、NH_(4)^(+)-N和DOC含量均有显著影响(P上坡位>中坡位,而土壤NO_(3)^(−)-N、NH_(4)^(+)-N和DOC含量沿坡面的变化趋势大小则为:上坡位<中坡位<下坡位.退耕林地土壤仅DOC含量受坡位的显著影响,并沿坡面向下呈增加趋势.结果表明,在评估紫色土丘陵区土地利用变化对土壤碳氮储量的影响时,不能忽视地形等因素的影响.

关键词：紫色土退耕还林坡位土壤氮(N) 土壤碳(C) 空间分布