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Chinese Geographical Science 2008年第3期18卷 276-283页

作者： LIAO Fuqiang ZHOU Shenglu ZHANG Hongfu WU Shaohua ZHAO Qiguo school of Geography and Ocean Science Nanjing University Nanjing 210093 China school of Geography and environment Jiangxi Normal University Nanchang 330022 China Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

According to the historical changes of coastal lines, seven soil sampling districts, from land to sea, were arranged in Dongtai City, Jiangsu Province to sample soils from surface and profile. Concentrations of seven major heavy metals (HMs), granularity, pH, organic matters and C/N of the soil samples were analyzed. Results show that concentrations of heavy metals in agricultural land present a certain spatial variance, decreasing from land to sea. Pollution assessment indicates that the agricultural soils were not polluted by HMs, but the potential pollution of Cu and Hg needs to be alerted. Different HMs accumulate in the surface and sub-surface of the soil profiles, and concentrations of Hg and Pb decrease significantly with the increment of soil depth. Concentrations of HMs exhibit a significantly negative correlation to pH, but have no significant relation with organic matters in soil. Principle component analysis show that the concentrations of HMs relate to the land use history. Concentrations of Hg, Ni and Cr in soil are closely related with land use history, and concentrations of Pb, Cu and Cr are affected by land use history as well as other factors. However, there is no significant relation between concentration of As and land use history.

关键词： coastal zone agriculture land heavy metal land use history

Indian Ocean-MORB-type isotopic signature of Yushigou ophiolite in North Qilian Mountains and its implications

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Science China earth sciences 2006年第6期49卷 561-572页

作者： HOU Qingye1,2, ZHAO Zhidan1,2, ZHANG Hongfei3, ZHANG Benren3 & CHEN Yuelong2 1. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China 2. school of earth Science and Mineral Resources, China University of Geosciences, Beijing 100083, China 3. Faculty of earth sciences, China University of Geosciences, Wuhan 430074, China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China school of earth Science and Mineral Resources China University of Geosciences Beijing China Faculty of earth sciences China University of Geosciences Wuhan China

In order to explore the disputed issue concerning the tectonic affinity ofthe ancient ocean mantle of North Qilian Mountains (NQM), geochemical and Sr, Nd, Pb isotopiccompositions of pillow basalts of the Yushigou Ophiolite (YSGO) suite from NQM have been analyzedsystematically. The pillow basalts exhibit tholeiitic characteristics, with flatchondrite-normalized REE patterns ((La/Yb)_N = 0.98—1.27). They display no Nb, Ta, Zr, Hf negativeanomalies, and show MORB features in 2Nb-Zr/4-Y and Ti/100-Zr-YX3 tectonic discrimination *** results indicate that the Yushigou ophiolite is most likely to be formed in a mid-ocean ridgeor mature back-arc basin. Their isotopic data show a relatively broad and enriched ^(87)Sr/^(86)Sr(0.70509 — 0.70700), restricted ^(143)Nd/^(144)Nd (0.512955-0.512978). Pb isotopes are in the rangeof ^(206)Pb/^(204)Pb (18.054-20.562), ^(207)Pb/^(204)Pb (15.537-15.743) and ^(208)Pb/^(204)Pb(38.068-38.530). These isotopic data imply that the basalts originated from the depleted mantle(DMM), with the involvement of enriched mantle components (mainly EMII). Geochemical comparisonsbetween the basalts in YSGO and the MORB-type basalts of ophiolite suites occurring in the knownancient Tethyan tectonic domain indicate that the ancient oceanic mantle represented by YSGO suiteforming in early Paleozoic in the North Qilian Moutains is very similar to the Tethyan mantle inboth trace elements and isotopic compositions. The North Qilian Mountains should be a part of theTethyan tectonic domain in early Paleozoic. This further implies that the Tethyan tectonic domaincan be deduced to early Paleozoic in the study area, which will be helpful to discussing thetectonic affinity and evolution of the North Qilian Mountains.

关键词： geochemistry, Indian Ocean-MORB-type isotopic signatures, Tethyan tectonic domain, Yushigou ophiolite, North Qilian Mountains.

Spatial and temporal distribution of the cloud optical depth over China based on MODIS satellite data during 2003–2016

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Journal of environmental sciences 2019年第6期31卷 66-81页

作者： Xiaopan Li Huizheng Che Hong Wang Xiang'ao Xia Quanliang Chen Ke Gui Hujia Zhao Linchang An Yu Zheng Tianze Sun Zhizhong Sheng Chao Liu Xiaoye Zhang Plateau Atmospheric and environment Laboratory of Sichuan Province College of Atmospheric Science Chengdu University of Information Technology State Key Laboratory of Severe Weather LASW and Institute of Atmospheric Composition Chinese Academy of Meteorological SciencesCMA Laboratory for Middle Atmosphere and Global environment Observation LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences school of Geoscience University of Chinese Academy of Science school of Surveying and Land Information Engineering Henan Polytechnic University

The cloud optical depth(COD) is one of the important parameters used to characterize atmospheric clouds. We analyzed the seasonal variations in the COD over East Asia in 2011 using cloud mode data from the AERONET(Aerosol Robotic Network) ground-based observational network. The applicability of the MODIS(Moderate Resolution Imaging Spectroradiometer) COD product was verified and compared with the AERONET cloud mode dataset. There was a good correlation between the AERONET and the MODIS. The spatial and temporal distribution and trends in the COD over China were then analyzed using MODIS satellite data from 2003 to 2016. The seasonal changes in the AERONET data and the time sequence variation of the satellite data suggest that the seasonal variations in the COD are significant. The result shows that the COD first decreases and then increases with the season in northern China, and reaches the maximum in summer and minimum in ***, the spatial distribution change is just the opposite in southern China. The spatial variation trend shows the COD in China decreases first with time and gradually increases after 2014. And the trend of COD in the western and central China is consistent with that in China. While the trend of COD shows a continuously increasing over time in northeast China and the Pearl River Delta.

关键词： Sun photometer MODIS COD Verification

Relationship of Old World Pseudoxenodon and New World Dipsadinae,with Comments on Underestimation of Species Diversity of Chinese Pseudoxenodon

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Asian Herpetological Research 2013年第3期4卷 155-165页

作者： Baolin ZHANG Song HUANG College of Life and environment sciences Huangshan University school of Life sciences Yunnan University State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences Institute of Biodiversity and Geobiology Department of Life SciencesTibet University

Assessment of the relationship between Pseudoxenodon and Dipsadinae has been hampered by lack of adequate samples. In this paper, we conducted phylogenetic analyses using two mitochondrial genes （12S and 16S rRNA） and one nuclear gene （c-mos） from thirteen specimens representing two species of Pseudoxenodon, together with 84 sequences of caenophidians and an outgroup sequence of Boa constrictor. Our study suggests that the Southeast Asian genus, Pseudoxenodon forms a robust genetic subclade within South American xenodontines, indicating that at least one lineage within this genus entered or returned to the Old World （OW） from the New World （NW） across the Beringian Land Bridge during the early Tertiary and the warm mid-Miocene. It also reveals the high intraspecific genomic variation within the populations of Pseudoxenodon macrops, indicating that species diversity of Pseudoxenodon in China is likely underestimated.

关键词： phylogenetic position 12S rRNA 16S rRNA Beringian Land Bridge cryptic species

Estimating the impact of land use change on surface energy partition based on the Noah model

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Frontiers of earth Science 2014年第1期8卷 18-31页

作者： Shaohui CHEN Hongbo SU Jinyan ZHAN Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China school of environment Beijing Normal University Beijing 100875 China

It is well known that land use has an important impact on surface energy partition. It is important to study the evolving trend of the partition of sensible heat flux （SHF） and latent heat flux （LHF） from the net radiance （NR） with land use change in the context of regional climate changes. In this paper, we studied the response of energy partition to land use using the Noah model. First, the Noah model simulation results of SHF and LHF between 2003 and 2005 were comprehensively validated using the observation data from the Changbai Mountain Station, the Xilinhot Station, and the Yucheng Station. The study domains represent three different types of land use change： excessive deforestation, grassland degeneration aggravation, and groundwater level decline, respectively. The study period was subsequently extended from 2015 through 2034, using four projected land use maps and forcing data from Princeton （2000-2004）. The simulation results show that during the land use conversions, the annual average of LHF drops by 10.7%, rises by 10.1%, and drops by 11.5% for the Changbai Mountain, Inner Mongolia, and Northern China stations, respectively while the annual average of SHF rises by 10.6%, drops by 10.1%, and drops by 11.3% for the three areas.

关键词： sensible heat flux latent heat flux land use change the Noah model

Predisposing factors’effects on mortality of oak (Quercus) and hickory (Carya) species in mature forests undergoing mesophication in Appalachian Ohio

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Forest Ecosystems 2021年第1期8卷 81-94页

作者： Don C.Radcliffe David M.Hix Stephen N.Matthews school of environment and Natural Resources The Ohio State University2021 Coffey RoadColumbus OH 43210USA school of environmental and Forest sciences University of WashingtonBox 352100Seattle WA 98195-2100USA

Background:Mature oak(Quercus spp.)and hickory(Carya spp.)trees are gradually being replaced by more shadetolerant tree species across the eastern U.S.,likely due to fire suppression and increased *** and hickories are highly valuable to wildlife;therefore,studying their mortality patterns can provide information on the longevity of habitat quality for many animal *** mortality has most often been studied following large oak decline events,but background mortality rates in forests with aging oak and hickory canopies warrant equal attention,especially in the context of widespread oak and hickory regeneration ***:We studied background mortality rates of five oak and one hickory species over a 23–25 year time period(1993–1995 to 2018),using 821/20th hectare permanent plots on the Marietta Unit of the Wayne National Forest in southeastern *** calculated mortality rates based on remeasurement of individual trees for white oak(Quercus alba),chestnut oak(Quercus montana),northern red oak(Quercus rubra),black oak(Quercus velutina),scarlet oak(Quercus coccinea),and pignut hickory(Carya glabra).For each of these species other than scarlet oak,we also modeled the relationships of mortality probability with a priori topographic,soil,stand structural,and individual tree covariates,using a mixed-effects logistic regression ***:The species with the highest mortality rate was scarlet oak(61.3%),followed by northern red oak(41.4%),black oak(26.7%),pignut hickory(23.9%),white oak(23.4%),and chestnut oak(19.1%).In our models,northern red oak mortality was associated with more mesic slope positions,shallower solums,more acidic soils,and older stand *** hickory and chestnut oak mortality rates were associated with higher basal areas on the plot,while white oak mortality showed the opposite ***:Our data suggest that red oak subgenus trees in mature forests of our area will become increasingly uncommon relative t

关键词： Mortality Quercus Carya Mesophication Wildlife habitat

Microfacies Analysis and Paleoecology of the Oligocene Succession in a Central Tethyan Carbonate Platform,Zagros Basin,SW Iran

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1634-1646页

作者： Tahereh HABIBI Department of earth sciences College of ScienceShiraz UniversityShiraz 71454Iran

Two stratigraphic sections(Arjooieh and Firoozabad)of the Mymand anticline,located in the Interior Fars subbasin of the Zagros Mountains,were measured and sampled,in order to document sedimentological characteristics,microfacies types and paleo-seagrasses indicators of the Oligocene succession(Asmari Fm.).Planktonic and benthic foraminifera and coralline red algae are the principal fossils from these *** are represented by the following families:Soritidae,Peneroplidae,Austrotrillinidae,Alveolinidae,Planorbulinidae,Discorbidae,Lepidocyclinidae,Amphisteginidae,Rotaliidae,Nummulitidae and *** microfacies types were recognized,namely planktonic foraminifera-peloidal packstone(MF1),bioclast nummulitid/Nerorotalia/Amphistegina packstone-grainstonerudstone-floatstone(MF2),Neorotalia-echinoid coralline red algae packstone-grainstone(MF3),coral boundstone(MF4),coral/coralline red algae rudstone-floatstone-packstone-grainstone(MF5),diverse imperforate foraminifera bioclast packstone-grainstone(MF6),peloid wackestone-packstone-grainstone(MF7),fenestrated mudstone and microbial mats(MF8)and anhydrite(MF9).MF1 indicates an outer ramp,MFs 2-4 represent a mid-ramp and MFs 5-9 are interpreted as inner ramp ***-seagrass indicators consisting of foraminifera,hooked and tabular forms of coralline red algae and *** were identified in MFs 5 and 6,reflecting the presence of vegetated environments within the mid/inner ramp *** Mymand anticline was dominated by the outer ramp environment at the start of the *** to inner ramp environments prevailed during the *** Chattian corresponds to the spread of the inner ramp setting over the Mymand anticline.

关键词： microfacies paleo-seagrass carbonate ramp foraminifera Oligocene

Localized temporal variation of earth's inner-core boundary from high-quality waveform doublets

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earthquake Science 2015年第3期28卷 175-185页

作者： Danhua Xin Xiaodong Song Tao Wang Institute of Geophysics and Geodynamics School of Earth Sciences and Engineering Nanjing University Department of Geology University of Illinois at Urbana-Champaign

The topography of the inner core is crucial to understand its growth process and interaction with the geodynamo. With the accuracy of teleseismic waveform doublets in determining the travel-time shifts between PKPcd and PKPdf inner-core phases, we examined the temporal change of the inner-core boundary sampled by new earthquake doublets that occurred in the Western Pacific and those previously found from the South Sandwich Islands. The receiver stations are those within the distance range of 128°–142° from the hypocenters of the waveform doublets. Our results suggest that temporal changes in PKPcd-PKPdf differential times are very subtle except some isolated regions under central America and Africa. The observations may indicate localized topography of the inner core and/or the inner-core boundary as transient slurry in isolated regions.

关键词： Waveform doublet Inner-core boundary topography Temporal change PKP

Newly discovered youngest UHT metamorphism on earth,Western Sulawesi,Indonesia

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Geoscience Frontiers 2023年第2期14卷 14-26页

作者： Juiyen Hsia Jian Zhang Guochun Zhao Jiahui Qian Jin Liu Min Sun Changqing Yin Peng Gao Welson Weisheng Xian Minjie Guo school of earth sciences and Engineering Sun Yat-sen UniversityGuangzhouChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina Department of earth sciences University of Hong KongPokfulam RoadHong KongChina College of earth sciences Jilin UniversityChangchunChina Pt.Enersteel Jl.Pejaten Barat II No.20 Kav.CSouth Jakarta 12510Indonesia

Ultrahigh-temperature(UHT)metamorphism represents an extreme crustal thermal event with peak conditions exceeding 900C at 7–13 *** the modern-style plate tectonic system,records of the UHT metamorphism are relatively rare due to the secular cooling of *** the Palu region of Western Sulawesi,we newly discovered a series of HT-UHT metamorphic rocks including amphibolite,granulite,eclogites and *** them,two granulite samples(18CS14-2,18CS14-4)with high garnet content(>50 mol%)are chosen for petrographic observation,phase equilibrium modelling,and zircon U-Pb *** rocks are characterized by a relic M1 assemblage of Grt+Ky+Bt+Rt and a M2 assemblage of Grt+Sil+Pl+Spl+Crd±Qtz+Ilm+*** equilibrium modelling based on effective bulk compositions yields UHT conditions of 7.2–8.5 kbar/940–1080C(18CS14-2)and 7.0–7.3 kbar/1000–1040C(18CS14-4).U-Pb analysis reveals two generations of metamorphic zircon with evolving REE content that is intimately related to garnet growth and *** age of 36–5.3 Ma is ascribed to syn-to post-M1 metamorphism,whereas the young zircon age of 5.1–3.8 Ma is linked to syn-and post-M2 *** UHT metamorphism was probably the consequence of the upwelling of asthenospheric mantle triggered by post-collisional delamination of lithosphere in the MiocenePliocene(ca.5 Ma).It could represent the youngest known UHT metamorphism on earth.

关键词： UHT metamorphism Granulite Sulawesi Indonesia Lithosphere delaimination

Foraminifera in Cenozoic Paleoenvironments

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Journal of China University of Geosciences 2005年第3期16卷 200-218页

作者： Brian Mc Gowran school of earth & environmental sciences Mawson Building DP313 The University of Adelaide Adelaide SA 5005 Australia

Paleontologists search the fossil record for evidence of age, ancient environments, phylogenetic reconstructions and ancient communities. Cenozoic foraminifera preserve evidence for all of these simultaneously from the water column and from at, above and below the sediment/water interface. As our understanding of foraminiferal assemblages and their place in the strata （biofacies） becomes more sophisticated, so are foraminiferal biofacies challenged to contribute to more subtle problems in Cenozoic earth and life history. Progress is described as a series of five ＂integrations＂. （Ⅰ） The quantification of foraminiferal biofacies was an advance on simple presences and absences of species meeting such questions as marine or nonmarine, or shallow or deep. （Ⅱ） Foraminiferal shells carry geochemical signals especially isotopes of oxygen （temperature, ice volume）, carbon （nutrition and the carbon cycle）, and strontium （seawater ratios through time）. （Ⅲ） From modern foraminiferal biology we have lifestyle insights leading to a model of oceans and paleo-oceans called the trophic resource continuum, a valuable way into greenhouse-icehouse comparisons and contrasts. （Ⅳ） Biofacies changes in space and time are sometimes abrupt with little evidence of diachrony, and sometimes gradual. These patterns are clarified in the context of sequence stratigraphy （which they enrich in turn）. （Ⅴ） The paleobiological counterpart of sequence stratigraphy is evolutionary paleoecology, reconstructing communities in deep time. The foraminifera are perfectly suited to investigate the possibility （or likelihood） that global environmental shifts have controlled community turnover in the pelagic, neritic and terrestrial realms.

关键词： foraminifera biofacies stratigraphy paleoecology paleoenvironment evolution Cenozoic trophic resource continuum