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A temporal framework for building up of healthy soils

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 292-296页

作者： Junling zhang Jiangzhou zhang Yunlong zhang guangzhou WANG State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Inner Mongolia Key Laboratory of Soil Quality and Nutrient Resources College of GrasslandResources and EnvironmentInner Mongolia Agricultural UniversityHohhot 010018China Key Laboratory of Grassland Management and Utilization Ministry of Agriculture and Rural Affairs of the People’s Republic of ChinaCollege of Grassland Science and TechnologyChina Agricultural UniversityBeijing 100193China

Healthy soils are vital for the diverse services provided by ecosystems to human society~[1], such as provisioning(food,fiber, timber, and fuel), regulation(climate, disease, and natural hazards), waste treatment, nutrient cycling, and cultural services. Soil has a three phase system and the interactions between soil chemical, biological, and physical attributes determine functions(hydraulic, thermal, and gas fluxes).

关键词： soils soil cycling

Soils for food security

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 213-215页

作者： guangzhou WANG Qichao ZHU Junling zhang State Key Laboratory of Nutrient Use and Management National Academy of Agriculture Green DevelopmentCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Food security is among the most fundamental of national interests and productive farmland is essential for secure grain *** the increase of agricultural intensification and the impact of global climate change,the soil... 详细信息

关键词： farmland security earth

Impact of EnKF assimilating Himawari-8 all-sky infrared radiance on the forecasting of a warm-sector rainstorm event

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Science china Earth Sciences 2024年第10期67卷 3110-3127页

作者： Shanshan LOU Lei ZHU Xuexing QIU guangzhou CHEN Song YUAN Shengnan ZHOU Anhui Meteorological Observatory Hefei 230031China Key Laboratory of Meteorological Disaster Ministry of Education(KLME)Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Joint International Research Laboratory of Climate and Environment Change(ILCEC)Nanjing University of Information Science&TechnologyNanjing 210044China Huaihe River Basin Meteorological center Hefei 230031China Shouxian National Climatology Observatory Huaihe River Basin Typical Farm Eco-Meteorological Experiment Field of CMAShouxian National Comprehensive Meteorological Observation Special Experimental OutfieldShouxian 232200China Anhui Province Key Laboratory of Atmospheric Science and Satellite Remote Sensing Hefei 230031China

Warm-sector rainstorms are highly localized events, with weather systems and triggering mechanisms are not obvious,leading to limited forecasting capabilities in numerical models. Based on the ensemble Kalman filter(PSU-En KF) assimilation system and the regional mesoscale model WRF, this study conducted a simulation experiment assimilating all-sky infrared(IR)radiance for a warm-sector rainstorm in East china and investigated the positive impact of assimilating the Himawari-8 moisture channel all-sky IR radiance on the forecast of the rainstorm. Results indicate that hourly cycling assimilation of all-sky IR radiance can significantly improve the forecast accuracy of this warm-sector rainstorm. There is a notable increase in the Threat Score(TS), with the simulated location and intensity of the 3-hour precipitation aligning more closely with observations. These improvements result from the assimilation of cloud-affected radiance, which introduces more mesoscale convective information into the model's initial fields. The adjustments include enhancements to the moisture field, such as increased humidity and moisture transport, and modifications to the wind field, including the intrusion of mid-level cold air and the strengthening of lowlevel convergent shear. These factors are critical in improving the forecast of this warm-sector rainstorm event.

关键词： Ensemble Kalman filter WRF model Himawari-8 All-sky radiance Warm-sector rainstorm

Saline-alkali soil reclamation and utilization in china:progress and prospects

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 216-228页

作者： guangzhou WANG Gang NI Gu FENG Haley MBURRILL Jianfang LI Junling zhang Fusuo zhang State Key Laboratory of Nutrient Use and Management(SKLNUM) College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China The Institute of Ecology and Evolution University of OregonEugeneOR97403USA

Soil salinity is a global threat to the productivity of arable land. With the impact of population growth and development of social economy in china, the area of arable land has been shrinking in recent decades and is approaching a critical threshold of 120 Mha, the minimum area for maintaining the national food security. Saline-alkaline land, as important backup reserve, has been receiving increased attention as an opportunity to expand land resources. This review first summarizes the general principles and technologies of saline soil reclamation to support plant growth, including leaching salts or blocking the rise of salts, and soil fertility enhancement to improve the buffering *** the progress in this area in china is described including the customization of technologies and practices used in different saline-alkali regions. Following the soil management strategies, the concept of selecting crops for saline soil is proposed. This encompasses halophyte planting, salt-tolerant crop breeding and the application of saline-adapted functional microorganisms to improve the adaptation of crops. Finally, the current problems and challenges are evaluate, and future research directions and prospects proposed for managing this major soil constraint.

关键词： Food security land reserve reclamation saline-alkali soil utilization

Chandra observations of the H_2O megamaser galaxy Mrk1210

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Science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 960-968页

作者： zhang JiangShui & FAN JunHui center for astrophysics, guangzhou university, guangzhou 510006, china center for astrophysics Guangzhou University Guangzhou 510006 China

We present the first Chandra X-ray observations of the H2O megamaser galaxy Mrk1210 (UGC4203), a Seyfert 2 galaxy at an approximate distance of D～57.6 Mpc. The Chandra X-ray image, with by far the highest angular resolution (～1"), displays an unresolved compact core toward the nuclear region of Mrk1210. Comparisons with the previous X-ray observations in the nuclear emission and the spectral shape indicate a fairly stable phase between 2001 (BeppoSAX and XMM-Newton) and 2004 (Chandra) after a dramatic variation since 1995 (ASCA). The best-fit model of Chandra X-ray spectrum consists of two components. The soft scattered component can be best fitted by a moderately absorbed power-law model adding a spectral line at ～0.9 keV (possibly a Ne-Kα fluorescent line), while the hard nuclear component can be well reproduced by a heavily absorbed power-law model (NH～2×1023 cm-2) with an additional line at ～6.19 keV (close to the Fe-Kα fluorescent line). The derived absorption-corrected X-ray luminosity implies that the dramatic variation of spectral properties is caused by significant changes of the absorbing column density along the line-of-sight, while the intrinsic nuclear X-ray lu-minosity remains stable. In this case, the absorbers should be anisotropic and its size can be constrained to be less than 0.0013 pc. In addition, we also estimate the mass of central engine, the disk radius and the accretion rate of the accretion disk to be 107.12±0.31M⊙, ～1 pc and 0.006, respectively.

关键词： active galaxy nuclei Seyfert galaxy X-ray maser

Thorium anomaly on the lunar surface and its indicative meaning

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Acta Geochimica 2024年第3期43卷 507-519页

作者： jingyi zhang Jianzhong Liu center for Lunar and Planetary Science Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China university of Chinese Academy of Sciences Beijing 100049China

The Moon has been divided into three terranes:Procellarum KREEP Terrane(PKT),Feldspathic Highland Terrane(FHT),and South Pole-Aitken Terrane(SPAT),using globally measured Th and *** lunar evolu-tion models have predicted that a lunar magma ocean will produce a residual layer enriched in incompatible elements such as K,REE,and P(i.e.,KREEP)in the late age of crys-tallization;and that the distribution of thorium can be used as a proxy for determining the global distribution of *** thorium distribution in these three terranes is *** highest concentration of thorium is in PKT,the medium concentration of thorium is in SPAT,and almost none in *** what is the specific distribution in each of the terrane and what enlightenment can it tell us?Here we present and describe the detailed thorium distribution in PKT,SPAT,and FHT and provide some information for the origin of asymmetries on the lunar surface.

关键词： Procellarum KREEP Terrane(PKT) Feldspathic Highland Terrane(FHT) South Pole-Aitken Terrane(SPAT) KREEP Thorium abundance

Magmatic-hydrothermal Evolution and Mineralization Mechanisms of the Wangjiazhuang Cu(-Mo)Deposit in the Zouping Volcanic Basin,Shandong Province,china:Constraints from Fluid Inclusions

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 679-700页

作者： SHU Lei YANG Renchao SHEN Kun YANG Deping MAO guangzhou LI Min LIU Pengrui MA Xiaodong Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong 266590China Key Laboratory of Gold Mineralization Processes and Resource Utilization MNR/Key Laboratory of Metallogenic Geological Processes and Resource UtilizationShandong Province/Shandong Institute of Geological SciencesJinan 250013China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdaoShandong 266237China

The Wangjiazhuang Cu(-Mo)deposit,located within the Zouping volcanic basin in western Shandong Province,china,is unique in this area for having an economic *** order to expound the metallogenetic characteristics of this porphyry-like hydrothermal deposit,a detailed fluid inclusion study has been conducted,employing the techniques of representative sampling,fluid inclusion petrography,microthermometry,Raman spectroscopy,LA-ICP-MS analysis of single fluid inclusions,as well as cathode fluorescence spectrometer analysis of host mineral *** deposit contains mainly two types of orebodies,***-dissemination-stockwork orebodies in the K-Si alteration zone and pegmatiticquartz sulfide veins above *** addition,minor breccia ore occurs *** types of fluid inclusions in the deposit and altered quartz monzonite are identified:L-type one-or two-phase aqueous inclusions,V-type vapor-rich inclusions with V/L ratios greater than 50%-90%,D-type multiphase fluid inclusions containing daughter minerals or solids and S-type silicate-bearing fluid inclusions containing mainly muscovite and *** petrography and fluid inclusion study has revealed a three-stage mineralization process,driven by magmatic-hydrothermal fluid activity,as ***,a hydrothermal fluid,separated from the parent magma,infiltrated into the quartz monzonite,resulting in its extensive K-Si alteration,as indicated by silicate-bearing fluid inclusions trapped in altered quartz *** is followed by the early mineralization,the formation of quartz veinlets and dissemination-stockwork *** the main mineralization stage,due to the participation and mixing of meteoric groundwater with magmatic-sourced hydrothermal fluid,the cooling and phase separation caused deposition of metals from the hydrothermal *** a result,the pegmatitic-quartz sulfide-vein ores *** the late mineralization stage,decreasing fluid salinity led to the formation of L-type aqueous

关键词： fluid inclusions fluid immiscibility mineralization mechanisms Wangjiazhuang Cu(-Mo)deposit

Discussion on event horizon and quantum ergosphere of dynamic rotating black holes in a tunneling framework

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Chinese Physics B 2012年第7期21卷 162-167页

作者：刘佰生张靖仪 center for astrophysics Guangzhou University

According to the Parikh–Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identical with the tunneling potential barrier set by particle’s tunneling across the relevant horizon. Then, some discussions on the origin of the Hawking radiation will be shown.

关键词： Hawking radiation dynamic rotating black holes tunneling framework quantum ergosphere

Summary of the 11th Conference on Magnetic Confined Fusion Theory and Simulation

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Plasma Science and Technology 2024年第10期26卷 1-7页

作者： guangzhou HAO Jianqiang XU Youwen SUN Zhibin GUO Organizing Committee of the 11th Conference on Magnetic Confined Fusion Theory and Simulation Southwestern Institute of Physics Chengdu 610041People’s Republic of China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China State Key Laboratory of Nuclear Physics and Technology Fusion Simulation CenterSchool of PhysicsPeking UniversityBeijing 100871People’s Republic of China 不详

This conference report summarizes recent progress in plasma theory and simulation that was presented in contributed papers and discussions at the 11th Conference on Magnetic Confined Fusion Theory and Simulation(CMCFTS)held in Chengdu,china,27–30 October,*** in various fields has been *** example,results on zonal flow generation by mode coupling,simulations of the key physics of divertor detachment,energetic particle effects on magnetohydrodynamic(MHD)modes in addition to ion-and electron-scale turbulence,physics of edge coherent modes and edge-localized modes,and the optimization of ion heating schemes as well as confinement scenarios using advanced integrated modeling are presented at the *** this conference,the scientific research groups were organized into six categories:(a)edge and divertor physics;(b)impurity,heating,and current drive;(c)energetic particle physics;(d)turbulent transport;(e)MHD instability;and(f)integrated modeling and code development.A summary of the highlighted progress in these working groups is presented.

关键词： magnetic confined fusion(MCF) theory and simulation modeling tokamak