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Journal of Zhejiang University-science B(Biomedicine & Biotechnology) 2007年第7期8卷 486-492页

作者： XIE Wen-xia WANG Guang-huo ZHANG Qi-chun school ofEnvwonmental andresource science Zhejiang University Hangzhou 310029 China school of Chemistry and Environment science Qingdao University Qingdao 266071 China

Potential growth of two widely-grown hybrid rice varieties in the Jinhua district of Zhejiang Province, Shanyou63 for mid-rice and Xieyou46 for late rice, was simulated using a crop growth model of WOFOST. Parameters of the rice growth in WOFOST were calibrated through field experiments from 1999 to 2002 in Jinhua. The potential yield simulated with WOFOST was about 12 t/ha for Shanyou63 and 10 t/ha for Xieyou46, which are in good agreement with the highest recorded yield obtained in this area. Under farmers practice, current yield is about 7.5 t/ha for Shanyou63 and 6.5 t/ha for Xieyou46. There is a gap between the actual rice yield and the potential yield for these two hybrid rice varieties grown in this area. The attainable target yields were set to 70% to 75% of their potential yields for the two varieties. A recently developed software "Nutrient Decision Support System (NuDSS)" for irrigated rice was used to optimize nutrient management for these two rice varieties. According to NuDSS, the optimal fertilizer N requirement for the target yields was about 150 kg/ha for Shanyou63 and about 120 kg/ha for Xieyou46, which were only about 70% of the fertilizer N application under current farmers' practice. Comparing with farmers' practice, there is great potential to increase actual rice yields and to reduce fertilizer N use rates by improving rice crop management practice in Jinhua.

关键词： Rice WOFOST NuDSS Potential growth Nitrogen management

Preparation of Ag@AgCl-doped TiO_2/sepiolite and its photocatalytic mechanism under visible light

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Journal of Environmental sciences 2017年第10期29卷 43-52页

作者： Shaomin Liu Dinglong Zhu Jinglin Zhu Qing Yang Huijun Wu school of earth science and Environmental Engineering Anhui University of Science and Technology

A cube-like Ag@Ag Cl-doped TiO2/sepiolite（denoted Ag@Ag Cl–TiO2/sepiolite） was successfully synthesized via a novel method. X-ray diffraction, scanning electron microscopy, energy dispersion X-ray fluorescence, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and diffuse reflectance ultraviolet–visible spectroscopy were performed to determine the structure and physicochemical properties of Ag@Ag Cl–TiO2/sepiolite. SEM micrographs revealed that Ag@Ag Cl nanoparticles and TiO2 film are well deposited on the surface of tube-like sepiolite. As a result, Ag@Ag Cl–TiO2/sepiolite exhibits a red shift relative to TiO2/sepiolite. Photocatalytic experiments demonstrated that the dosage of catalysts plays an important role during photocatalysis. The photoelectrochemical activities of Ag@Ag Cl–TiO2/sepiolite and TiO2/sepiolite were also investigated. Photocurrent responses confirmed that the ability of Ag@Ag Cl–TiO2/sepiolite to separate photo-generated electron–hole pairs is stronger than that of TiO2/sepiolite. Methylene Blue degradation is also improved under alkaline conditions and visible light irradiation because more UOH is produced by visible light *** excellent catalytic ability is mainly attributed to the formed Ag nanoparticles and the Schottky barrier at the Ag/TiO2 interface. Active species analysis indicated that UO2-and h＋are implicated as active species in photocatalysis. Therefore, catalysts are excited to produce abundant electron–hole pairs after they absorb photons in photocatalysis.

关键词： Ag@AgCl Sepiolite Photocatalyst Photocurrent

Deciphering non-steady landscape evolution by in-situ cosmogenic nuclide depth profile

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science China earth sciences 2022年第3期65卷 490-502页

作者： Ye YANG Lifeng CUI Sheng XU Zhenping CAO Shuncheng ZHANG Congqiang LIU Institute of Surface-earth System science School of Earth System ScienceTianjin UniversityTianjin 300072China

In-situ cosmogenic nuclide s are receiving growing attention in surface earth system science in which the steady-state denudation is an important assumption for estimating the surface denudation of long-lived(103-106 years)***,distinguishing steady-state denudation and deciphering a reliable denudation rate from non-steady state denudation region are *** depth profile models for investigating the denudation rate,exposure age and inheritance are widely used for sediment and regolith of steady-state denudation *** we present in-situ co smogenic nuclides^(10)Be and^(26)Al from two typical granite regolithes from Jixian in Tianjin and Tengchong in Yunnan to model non-steady landscape evolution process by using steady state(Model 1)and non-steady state(Model 2,continuous exposure;Model 3 a,changed denudation rate;Model 3 b,abrupt denudation event)*** results of steady state model show that both regolithes are in non-steady state.^(10)Be non-steady state models of Jixian regolith reveal that the surface has likely experienced a denudation rate change or an abrupt denudation event during the past several millennia,resulting in a non-steady *** similar Model 3 a and 3 b denudation rates of 14.6-12.9^(+9.4)and 14.7-14.7^(+9.0)mmkyr^(-1),respectively,might demonstrate the long-term denudation rate rather than the exaggerated rate s of 39.0-2.3^(+2.6)and 39.0-2.4+^(2.5)mm kyr^(-1)calculated by assuming steady-state denudation and ignoring *** non-steady state model results of Tengchong regolith suggest that the surface has likely experienced a strong denudation about 157 ka(^(10)Be)or 127 ka(^(26)Al)*** timing is basically consistent with the termination of the MIS 6(TII:130 ka)and the climate change events in the Tibetan Plateau,suggesting a strong surface landscape denudation during the transition from glacial to *** compiling of basin-wide denudation rates in the Tibetan Plateau shows a good positi

关键词： Denudation rate Landscape evolution Quaternary geochronology Depth profile Cosmogenic nuclides

Geochemical characteristics of REE in the Late Neo-proterozoic limestone from northern Anhui Province, China

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Chinese Journal Of Geochemistry 2014年第2期33卷 187-193页

作者： CHEN Song GUI Herong SUN Linhua school of earth sciences and Engineering Suzhou University school of Resource and earth science CUMT

Ten representative limestone samples [six from Wangshan Formation(WL) and the other four from Gouhou Formation(GL)] were collected from outcrops of the northern Anhui Province, and REE concentrations in limestone were measured by ICP-MS. The depositional environment and source of the REE were analyzed, and the results implys that the total REE of samples are low compared with the recent marine sediments, which range from 9.61 to 54.18 mg/kg and an average of 22.93 mg/kg. The PAAS-normalized REE+Y patterns of limestone are characterized by(1) light REE depletion in WL and enrichment in GL with the values of(Nd/Yb)SN ranging form 0.65 to 0.91 and 1.12 to 1.46, respectively;(2) light negative Ce anomaly(0.85–1.02) and positive La anomaly(0.92–1.27); and(3) both Eu(0.91–1.23) and Y(1.42–2.38) expressing light positive anomaly. The character indicated that the depositional environment was oxygenated, with infection by the hydrothermal activity and contamination of detritus.

关键词：稀土元素灰岩样品地球化学特征安徽省晚新元古代中国 ICP-MS Ce异常

Upper mantle convection driving by density anomaly and a test model

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Acta Seismologica Sinica(English Edition) 2005年第1期18卷 27-33,124页

作者：傅容珊王景赟常筱华黄建华戴志阳查显杰 school of earth and Space science University of Science and Technology of China

A mathematic-physical convection model in upper mantle is established in this paper. This model is in a three dimensional frame. Assume that the density anomalies, which are mapped from the seismic tomography data, are responding to the temperature perturbation in the connective system. This model takes the density anomalies as the driving force for the mantle convection. We solve the basic equations with different boundary conditions in a domination of wave number by using the FFT arithmetic. In order to test the validity of our theory and method two simple models (higher-lower density body and break off slab) are employed to calculate their flow patters in this paper. Results show that our method can be directly used to investigate the upper mantle convection patterns and its related problems of lithospheric dynamics.

关键词： mantle convection dynamics seismic tomography

Erosions on the southern Tibetan Plateau:Evidence from in-situ cosmogenic nuclides^(10)Be and^(26)Al in fluvial sediments

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Journal of Geographical sciences 2022年第2期32卷 333-357页

作者： ZHANG Xiaolong XU Sheng CUI Lifeng ZHANG Maoliang ZHAO Zhiqi LIU Congqiang Institute of Surface-earth System science School of Earth System ScienceTianjin UniversityTianjin 300072China school of earth science and Resources Chang'An UniversityXi’an 710054China

Investigating topographic and climatic controls on erosion at variable spatial and temporal scales is essential to our understanding of the topographic evolution of the *** this work,we quantified millennial-scale erosion rates deduced from cosmogenic^(10)Be and^(26)Al concentrations in 15 fluvial sediments from the mainstream and major tributaries of the Yarlung Zangbo River draining the southern Tibetan Plateau(TP).The measured ratios of^(26)Al/^(10)Be range from 6.33±0.29 to 8.96±0.37,suggesting steady-state erosion *** resulted erosion rates vary from 20.60±1.79 to 154.00±13.60 m Myr-1,being spatially low in the upstream areas of the Gyaca knickpoint and high in the downstream *** examining the relationships between the erosion rate and topographic or climatic indices,we found that both topography and climate play significant roles in the erosion process for basins in the upstream areas of the Gyaca ***,topography dominantly controls the erosion processes in the downstream areas of the Gyaca knickpoint,whereas variations in precipitation have only a second-order *** marginal Himalayas and the Yarlung Zangbo River Basin(YZRB)yielded significantly higher erosion rates than the central plateau,which indicated that the landscape of the central plateau surface is remarkably stable and is being intensively consumed at its boundaries through river headward *** addition,our^(10)Be erosion rates are comparable to present-day hydrologic erosion rates in most cases,suggesting either weak human activities or long-term steady-state erosion in this area.

关键词： in-situ^(10)Be and^(26)Al ^(26)Al/^(10)Be ratio basin-scale erosion topographic and climatic control Yarlung Zangbo River southern Tibet

Geochemistry of sandstones from the Neoproterozoic Jinshanzhai Formation in northern Anhui Province, China: Provenance, weathering and tectonic setting

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Chinese Journal Of Geochemistry 2013年第1期32卷 95-103页

作者： SUN Linhua GUI Herong CHEN Song school of earth science and Engineering Suzhou University

Sandstones from the Neoproterozoic Jinshanzhai Formation in northern Anhui Province, China, were analyzed for major oxides and trace elements to infer their provenance, the intensity of paleo-weathering of their source rocks and the depositional tectonic setting. Diagrams of (SiO2/20)-(Na2O+K2O)-(MgO+TiO2+FeO*), TiO2-Ni, Th-Hf-Co, Hf-La/Th and some ratios of elements indicate that felsic rocks constitute the source rocks in the provenance. The values of Chemical Index of Alteration (CIA) are low, which are considered to be affected by K-metasomatism. Whereas the high CIW (Chemical Index of Weathering) values indicate intensive weathering of the source material. Plots of sandstones on bivariate and triangle discriminant diagrams, as well as ICV (Index of Compositional Variation) values revealed that they were deposited on a passive continental margin or in an intra-plate basin. Our recent study, in combination with previous studies and the research progress of the Rodinia super continent, demonstrated that the convergence and extension of the Rodinia super continent were preserved by twice extension as expressed by petrological variation of the southeastern margin of the North China Craton (NCC) during the Neoproterozoic.

关键词：沉积构造背景中国北方新元古代地球化学特征安徽省 Rodinia超大陆砂岩耐候性

A Framework for Disaster Vulnerability in a Small Island in the Southwest Pacific: A Case Study of Emae Island, Vanuatu

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International Journal of Disaster Risk science 2017年第4期8卷 358-373页

作者： Guy Jackson Karen McNamara Bradd Witt school of earth and Environmental science The University of Queensland

The societal costs of disasters around the world are continuing to increase and Pacific Island countries are considered some of the most vulnerable. This is primarily due to a combination of high hazard exposure coupled with a range of social, economic, physical, and political vulnerabilities. This article contributes to the growing body of work that aims to understand the causal factors of disaster vulnerability, but with a specific focus on small island developing states. The article first develops a framework for understanding disaster vulnerability, drawing on extensive literature and the well-established Methods for the Improvement of Vulnerability in Europe(MOVE)framework, and second, applies this adapted framework using empirically-derived data from fieldwork on Emae Island, Vanuatu to provide a working understanding of the causal elements of disaster vulnerability. Drawn from a significant body of scholarship at the time, the MOVE framework was primarily developed as a heuristic tool in which disaster vulnerability is considered to be a function of exposure, susceptibility(socially, economically, physically, culturally, environmentally, institutionally), and a lack of resilience. We posit that this adapted framework for small islands should also include historical susceptibility,and we prefer livelihood resilience(as capabilities, social capital, knowledge, participation, and human rights) over lack of resilience. We maintain that understanding disaster vulnerability holistically, which is inclusive of both strengths and drawbacks, is crucial to ensure that limited resources can target the causal factors that produce vulnerability and help safeguard and improve livelihoods in both the short and long term.

关键词： Disaster risk reduction Disaster vulnerability Livelihood resilience Small islands Vanuatu

Stress field modeling of northwestern South China Sea since 5.3 Ma and its tectonic significance

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Acta Oceanologica Sinica 2013年第12期32卷 31-39页

作者： YANG Fengli ZHOU Zuyi ZHANG Na LIU Ning NI Bin school of Ocean and earth science Tongji University

Tectonically,the northwestern South China Sea(SCS)is located at the junction between three micro-plates,i.e.,the Indochina,South China and Zhongsha-Xisha micro-plates,and involves three basins,i.e.,the Yinggehai Basin,the Qiongdongnan Basin and Xisha Trough in the east,and the Zhongjiannan Basin in the *** the Pliocene(5.3 Ma),the Yinggehai Basin has experienced repeated accelerating subsidence,high thermal fluid,and widely developing mud-rich overpressure chambers,abundant mud diapers and crust-mantle mixed *** a large central canyon was developed in the Qiongdongnan Basin,new rift occurred in the Xisha *** characteristics demonstrate a single tectonic unit for the northwestern SCS,for which we have undertaken stress field modeling to understand its plate deformations and sedimentary *** results demonstrate that an extension tectonic event occurred after 5.3 Ma in the Yinggehai-Qiongdongnan-Xisha trough area,which is characterized by thinner crust(3 500 m).A new rift system subsequently was developed in this area;this event was mainly driven by the combined effects of different movement velocity and direction of the three micro-plates,and the far-field effect of the continental collision between the Indian Plate and the Tibetan Plateau,and subduction of the Pacific Plate underneath the Eurasian Plate.

关键词： northwestern South China Sea Pliocene stress field modeling rift system

The transport of water in subduction zones

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science China earth sciences 2016年第4期59卷 651-682页

作者： ZHENG YongFei CHEN RenXu XU Zheng ZHANG ShaoBing school of earth and Space sciences University of Science and Technology of China

The transport of water from subducting crust into the mantle is mainly dictated by the stability of hydrous minerals in subduction zones. The thermal structure of subduction zones is a key to dehydration of the subducting crust at different depths. Oceanic subduction zones show a large variation in the geotherm, but seismicity and arc volcanism are only prominent in cold subduction zones where geothermal gradients are low. In contrast, continental subduction zones have low geothermal gradients, resulting in metamorphism in cold subduction zones and the absence of arc volcanism during subduction. In very cold subduction zone where the geothermal gradient is very low(?5?C/km), lawsonite may carry water into great depths of ?300 km. In the hot subduction zone where the geothermal gradient is high(>25?C/km), the subducting crust dehydrates significantly at shallow depths and may partially melt at depths of <80 km to form felsic melts, into which water is highly dissolved. In this case, only a minor amount of water can be transported into great depths. A number of intermediate modes are present between these two end-member dehydration modes, making subduction-zone dehydration various. Low-T/low-P hydrous minerals are not stable in warm subduction zones with increasing subduction depths and thus break down at forearc depths of ?60–80 km to release large amounts of water. In contrast, the low-T/low-P hydrous minerals are replaced by low-T/high-P hydrous minerals in cold subduction zones with increasing subduction depths, allowing the water to be transported to subarc depths of 80–160 km. In either case, dehydration reactions not only trigger seismicity in the subducting crust but also cause hydration of the mantle wedge. Nevertheless, there are still minor amounts of water to be transported by ultrahigh-pressure hydrous minerals and nominally anhydrous minerals into the deeper mantle. The mantle wedge overlying the subducting slab does not partially melt upon water influx

关键词： Subduction zones Oceanic crust Mantle wedge Thermal structure Hydrous minerals Water transport Arc magmatism