检索结果-南通市图书馆

Chemical weathering processes in the Chinese Loess Plateau

Geoscience Frontiers 2024年第5期15卷 197-209页

作者： Ningpan Chai Zhiqi Zhao Xiaoke Li Jun Xiao Zhangdong Jin School of earth Science and Resources Chang’an UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Xi’an institute for Innovative {1. environment Research Xi’an 710061China

Covered by erodible loess and affected by significant seasonal climate variations,chemical weathering in the Chinese Loess Plateau(abbreviated as CLP)has important effects on the hydrochemistry of the Yellow River and the global carbon ***,chemical weathering processes in the CLP are still *** on 296 river water samples in the CLP in the different seasons,hydrochemistry,weathering processes,and their controlling factors were *** waters in the CLP exhibited slightly alkalinity(pH=8.4±0.5)with much high total dissolved solids(TDS)values(691.81. mg/L).The water types of river water in the CLP were primarily SO_(4)^(2-)-Cl^(-)-Na^(+),HCO_(3)^(-)-Ca^(2+)-Mg^(2+),and SO_(4)^(2-)-Cl^(-)-Ca^(2+)-Mg^(2+).According to the forward model,evaporite dissolution has the largest contribution(55.1.±0.2%)to riverine solutes in the CLP,then followed by carbonate weathering(35.6%±0.2%)and silicate weathering(6.5%±0.1.).For spatio-temporal variations,the contribution of evaporite dissolution in the CLP decreased from northwest to southeast with higher proportion in the dry season,carbonate weathering increased from northwest to southeast with a higher proportion in the wet season,and silicate weathering showed minor spatio-temporal ***^(2+)and Mg^(2+)were affected by carbonate precipitation and/or incongruent calcite dissolution,and about 50%of samples exhibited cation exchange *** physical erosion rate in the CLP,which was 372±293 t·km^(-2)·yr^(-1.,varied greatly and was greater than those of other worldwide *** weathering rates in the CLP showed an increasing trend *** the wet season,high runoff led to the release of evaporite and carbonate from loess,while the interfacial reaction kinetic limited the increase of the silicate weathering *** CO_(2)consumption budget by carbonate weathering(6.1.1.^(1.)mol/yr)and silicate weathering(1.6×1.^(1.)mol/yr)in the CLP accounted for 0.29%and 0.08%of the global carb

关键词： Chemical weathering Chinese Loess Plateau Spatio-temporal variations CO_(2)budget Physical erosion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular compositions and sources of organic aerosols at a rural site on the Guanzhong Plain,Northwest China:The importance of biomass burning

引用

Particuology 2024年第6期89卷 44-56页

作者： Yali Liu Minxia Shen Haijiao Liu Wenting Dai Weining Qi Yifan Zhang Lu Li Yue Cao Xin Wang Xiao Guo Yingkun Jiang Jianjun Li State Key Laboratory of Loess and Quaternary Geology Key Lab of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Xi'an institute for Innovative {1. environment Research Xi'an 710061China National Observation and Research Station of Regional Ecological environment Change and Comprehensive Management in the Guanzhong Plain ShaanxiChina

The concentration of PM_(2.5)has considerably reduced in recent years,but remains relatively high in *** particular,the increasing contribution of organic compounds to PM_(2.5)generates popular pressure for further reductions,resulting in an urgent need to study organic aerosol(OA).To investigate the molecular composition and source contribution of OA in the rural area of the Guanzhong Plain,Northwest China,PM_(2.5)samples were collected during 3–23 August 201. and 5–20 January 201. and studied for more than 1.0 organic tracer *** mean concentration of total measured organic compounds is 662±296 ng/m^(3)in summer and 3258±1.25 ng/m^(3)in *** is the most abundant single compound found throughout the sampling period,which is a crucial tracer for biomass burning emissions,preliminary suggesting that biomass burning is an essential source of *** summer,organic compounds such as lipid compounds,sugar compounds,and polycyclic aromatic hydrocarbons(PAHs),more come from higher plants,wood burning,vehicle exhausts,plastic waste,and other direct emission *** PAHs(OPAHs),nitrophenols,and phthalic acids more come from the atmosphere through the oxidation reaction of aromatic precursors,especially photochemical ***,in winter,most of the increases in concentrations of organic compounds are attributed to biomass *** analysis of a haze event(1.–1. January 201.)during the winter sampling period shows that the increases in the concentration of organic compounds are unaccompanied by strong secondary formation under lower relative humidity(49.1.±1..5%).The main reason for the growth of OA in this haze event is the accumulation of primary OA(POA).The source apportionment by the positive matrix factorization(PMF)model shows that biomass burning(37.1.)is the primary source of OA in the rural regions of the Guanzhong Plain,especially in winter(40.6%).The contribution of secondary formation decreases from 26.0%in summer t

关键词： Organic aerosol Molecular composition Seasonal variation Source apportionment Guanzhong Plain

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mobility of rhenium and selenium during chemical weathering and their implication for petrogenic organic carbon oxidation

引用

Science China earth Sciences 2024年第3期67卷 740-750页

作者： Yuhong ZHANG Jin WANG Yuanxin QU Chao ZHU Zhangdong JIN State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China Xi'an institute for Innovative {1. environment Research Xi'an 710061China institute of Global {1.al Change Xi'an Jiaotong UniversityXi'an 710049China

The oxidative weathering of petrogenic organic carbon(OC_(petro)) is an important source of carbon dioxide(CO_(2)) into the atmosphere on geological timescales and significantly influences the carbon cycle and global climate change. However, at present, a robust proxy to assess OC_(petro)oxidation is lacking. Riverine rhenium(Re) has emerged as a potential proxy to trace OC_(petro)oxidation, but little is known about Re sources and its relationship with OC_(petro)oxidation. To better understand the robustness of this proxy, we analyzed a shale weathering profile from the early Cambrian Shuijingtuo Formation in Chengkou County, Chongqing City, to address the mobility of Re and selenium(Se) and their relationship with the oxidation of OC_(petro)by analyses of the elemental variation and sequential extraction. The results showed that the chemical index of alteration(CIA)increases from the fresh bedrock to the weathered sections, indicating enhanced weathering intensity. Based on the sequential extraction and mass transfer coefficients(τ), Re and Se mainly exist in the organic phase of shale and are paired lost with OC_(petro) during weathering, with no obvious correlation with sulfide minerals. Furthermore, the different proportions of Re and Se loss with OC_(petro) loss can be attributed to their different geochemical behaviors during weathering. Our study supports Re as a robust proxy to trace OC_(petro) oxidation, whereas Se is the potential one. In the future, combined studies on various sedimentary rock profiles with catchment basins are needed to determine the sources of riverine Re and Se and their relationships with OC_(petro) oxidation.

关键词： Rhenium and selenium Shale Mobility OC_(petro) Chemical weathering

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Applications of mercury stable isotopes for tracing volcanism in the geologic record

引用

Science China earth Sciences 2024年第5期67卷 1436-1458页

作者： Qing GONG Ming-Xing LING Wang ZHENG State Key Laboratory of Nuclear Resources and environment East China University of TechnologyNanchang 330013China School of earth System Science Institute of Surface-Earth System ScienceTianjin UniversityTianjin 300072China

Mercury(Hg)enrichments in ancient sediments have been used as a proxy of volcanism,especially large igneous province(LIP)***,considering the existence of other potential Hg sources besides volcanoes and the diverse factors(e.g.,organic matters,clay minerals,sulfide minerals and Fe oxides)that can affect Hg sequestration,there are considerable uncertainties to simply regard sedimentary Hg anomalies as signatures of volcanic *** stable isotopes,a promising tool for tracing the origins and transformations of Hg,have been increasingly used for determining the causes of Hg spikes and understanding the geochemical behavior of Hg in the geologic *** date,lots of researches have applied Hg concentrations and Hg isotopes to identify LIP volcanisms linking with significant geological events such as mass extinctions,ocean anoxic events and other environmental perturbations that mainly occurred in the ***,the results in previous studies clearly show that not all Hg enrichments are derived from volcanic inputs,which emphasize the need for more caution in using Hg as a fingerprint of *** a better understanding of Hg isotopes in the future,there will be important implications for Hg isotopes to reconstruct volcanic activities in the rock records and their impacts on biological evolution.

关键词： Mercury stable isotopes Large igneous province Mass extinction event Ocean anoxic event

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Impacts of land surface darkening on frozen ground and ecosystems over the Tibetan Plateau

引用

Science China earth Sciences 2024年第10期67卷 3213-3225页

作者： Shuchang TANG Tao WANG Dan LIU Tandong YAO Shilong PIAO Sino-French institute for {1. System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100101China State Key Laboratory of Tibetan Plateau earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Tibetan Plateau(TP) is known as the “Third Pole” of the earth. Any changes in land surface processes on the TP can have an unneglectable impact on regional and global climate. With the warming and wetting climate, the land surface of the TP saw a darkening trend featured by decreasing surface albedo over the past decades, primarily due to the melting of glaciers, snow,and greening vegetation. Recent studies have investigated the effects of the TP land surface darkening on the field of climate, but these assessments only address one aspect of the feedback loop. How do these darkening-induced climate changes affect the frozen ground and ecosystems on the TP? In this study, we investigated the impact of TP land surface darkening on regional frozen ground and ecosystems using the state-of-the-art land surface model ORCHIDEE-MICT. Our model results show that darkening-induced climate changes on the TP will lead to a reduction in the area of regional frozen ground by 1.1.1.~4±0.01.×1.~4km~2, a deepening of the regional permafrost active layer by 0.06±0.0004 m, and a decrease in the maximum freezing depth of regional seasonal frozen ground by 0.06±0.001. m compared to the scenario without TP land surface ***, the darkening-induced climate change on the TP will result in an increase in the regional leaf area index and an enhancement in the regional gross primary productivity, ultimately leading to an increase in regional terrestrial carbon stock by0.81.0.001.PgC. This study addresses the remaining piece of the puzzle in the feedback loop of TP land surface darkening, and improves our understanding of interactions across multiple spheres on the TP. The exacerbated regional permafrost degradation and increasing regional terrestrial carbon stock induced by TP land surface darkening should be considered in the development of national ecological security barrier.

关键词： Tibetan Plateau Albedo Land surface darkening Frozen ground Ecosystem

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluation of the energy budget of thermokarst lake in permafrost regions of the Qinghai-Tibet Plateau

引用

Advances in Climate Change Research 2024年第4期15卷 636-646页

作者： Ze-Yong GAO Fu-Jun NIU Yi-Bo WANG Jing LUO Guo-An YIN Yun-Hu SHANG Zhan-Ju LIN Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of ScienceLanzhou 730000China College of earth and {1. Science Lanzhou UniversityLanzhou 73000China

Thermokarst lake formation accelerates permafrost degradation due to climate warming,thereby releasing significant amounts of carbon into the atmosphere,complicating hydrological cycles,and causing environmental ***,the energy transfer mechanism from the surface to the sediment of thermokarst lakes remains largely unexplored,thereby limiting our understanding of the magnitude and duration of biogeochemical processes and hydrological ***,herein,a typical thermokarst lake situated in the center of the Qinghai-Tibet Plateau(QTP)was selected for observation and energy budget *** results showed that the net radiation of the thermokarst lake surface was 95.1.1.6.9,and 32.3 W m^(-2) for the annual,ice-free,and ice-covered periods,respectively,and was approximately 76%of the net radiation consumed by latent heat *** in heat storage in the thermokarst lake initially increased from January to April,then decreased from April to December,with a maximum change of 48.1.W m^(-2) in *** annual average heat fuxes from lake water to sediments were 1.4 W m^(-2);higher heat fluxes occurred during the ice-free season at a range of 4.9-1..0 W m^(-2).The imbalance between heat absorption and release in the millennium scale caused the underlying permafrost of the thermokarst lake to completely *** present,the ground temperature beneath the lake bottom at a depth of 1. m has reached 2.0℃.The temperatures and vapor-pressure conditions of air and lake surfaces control the energy budget of the thermokarst *** findings indicate that changes in the hydrologic regime shifts and biogeochemical processes are more frequent under climate warming and permafrost degradation.

关键词： Qinghai-Tibet Plateau Thermokarst lake Energy budget Permafrost degradation Hydrological cycle

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Growth of nitrate contribution to aerosol pollution during wintertime in Xi'an,northwest China:Formation mechanism and effects of NH_(3)

引用

Particuology 2024年第4期87卷 303-315页

作者： Hui Su Ting Zhang Suixin Liu Yao Qu Huan Li Jiamao Zhou Zhuzi Zhao Qiyuan Wang Lu Li Minxia Shen Shuoyuan Chen Steven Sai Hang Ho Junji Cao State Key Laboratory of Loess and Quaternary Geology.Key Laboratory ofAerosol Chemistry and Plhysics Institute of Earth EnvironmentChinese Acadery of SciencesXi'an 710061China Xi'an institute for Innovative {1. environment Research Xi'an 710061China National pbservation and Research Station of Regional Ecological environment Change and Cornprehensive Management in the Guanzhong Plain Xi'an 710061China Shaanxi Key Laboratory of Atmospheric and Haze fog Pollution Prevention Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China School of Chemical and environmental Engineering Jiangsu University of TechnologyChangzhou 213001China Division of Atmospheric Sciences Desert Research InstituteReno NV89512United States institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

With the strengthened controls on SO2 emissions and extensive increases in motor vehicles'exhaust,aerosol pollution shifts from sulfate-rich to nitrate-rich in recent years in Xi'an,*** further gain insights into the factors on nitrate formation and efficiently mitigate air pollution,highly time-resolved observations of water-soluble inorganic ions(WSIIs)in PM_(2.5) were measured in a suburban area of Xi'an,China during *** concentration of total WSIIs is 39.8μg m-3 on average,accounting for 50.3%of PM_(2.5) *** contrast to a slight decrease in the mass fraction of SO_(4)^(2-),NO_(3)-shows a sig-nificant increase of the PM_(2.5) contribution with the aggravation of aerosol *** suggests the importance of NO_(3)-formation to haze ***,homogeneous reactions govern the formation of NO_(3)-,while alkali metals such as calcium and sodium play an additional role in retaining NO_(3)-in PM_(2.5) during clean ***,the heterogeneous hydrolysis reaction contributed more to NO_(3)-formation during the pollution periods under high relative *** investigation reveals that temperature,relative humidity,oxidant,and ammonia emissions facilitate rapid NO_(3)-*** the random forest(RF)model,NO_(3)-concentrations were successfully simulated with measured variables for the training and testing datasets(R2>0.95).Among these variables,CO,NH_(3),and NO_(2) were found to be the main factors affecting the NO_(3)-*** with the period without vehicle re-striction,the contributions of NO_(3)-and NH4+to PM_(2.5) mass decreased by 5.3%and 3.4%in traffic re-striction periods,*** vehicle restriction leads to the decreases of precursor gases of NO_(2),SO_(2),and NH_(3) by 1..8%,5.9%,and 27.6%,*** results demonstrate collaborative emission reduction of NO_(x) and NH_(3) by vehicle restrictions,and using new energy vehicles(or electric vehicles)can effectively alleviate particul

关键词： PM_(2.5) Water-soluble inorganic ions Nitrate formation Excess ammonium Vehicle restrictions

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Does the continuous wetting of the Tibetan Plateau contribute to the accelerated degradation of permafrost?

引用

Science China earth Sciences 2024年第5期67卷 1714-1718页

作者： Yuyang WANG Jinzhi DING Shilong PIAO Sino-French institute for {1. System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China State Key Laboratory of Tibetan Plateau earth System Environment and ResourcesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Global warming is causing the Tibetan permafrost to degrade, as evidenced by rising ground temperatures, thicker active layer thickness, thinner permafrost layer, and melting underground ice, etc.(Ran et al., 201.;Wang et al., 2020).The degradation of permafrost not only profoundly alters the carbon cycling processes in high-altitude ecosystems,thereby influencing the regional climate system, but also affects landscape hydrological connectivity。

关键词： Tibetan landscape altitude

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Drought decreases the positive impact of warming on an alpine grassland community

引用

Science China earth Sciences 2024年第10期67卷 3226-3238页

作者： Wang A Wangwang LV Yang ZHOU Bowen LI Jianping SUN Jingya LV Lanying CHEN Dorji TSECHEO Shiping WANG Key Laboratory of Tibetan Plateau earth Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China School of Ecology and environment Tibet UniversityLhasa 850000China University of the Chinese Academy of Sciences Beijing 100049China

Temperature and precipitation are the main factors determining plant community succession and aboveground net primary productivity(ANPP)in natural ***,most climate manipulative experiments have mainly focused on their impacts in isolation,especially in alpine *** we explored the relative effects and interaction of warming and precipitation alteration on succession and ANPP using a 7-year experiment involving warming with precipitation alteration(increase(IP)or decrease(DP))in precipitation relative to ambient precipitation(AP)on the Tibetan *** results showed that warming and warm-wet conditions increased species richness,diversity index,height and cover of overall ***,decreasing precipitation reduced them,but increased *** and the rate of change in community ***,warming mitigated the impacts of decreased precipitation on plant community composition,and the interactive effects of warming and altered precipitation on cover,height and plant ANPP varied with year and plant ***,warming increased community ANPP through increases in forb ANPP or non-dominant species ANPP and biodiversity regardless of change in ***,decreased precipitation reduced community ANPP via decreases in the ANPP of sedges and forbs and *** alteration affected the relationship between biodiversity and community ANPP regardless of warming(IP

关键词： Alpine grassland Climate warming Precipitation alteration Community composition Biodiversity Above-ground net primary productivity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

MEIC-global-CO_(2):A new global CO_(2)emission inventory with highly-resolved source category and sub-country information

引用

Science China earth Sciences 2024年第2期67卷 450-465页

作者： Ruochong XU Dan TONG Qingyang XIAO Xinying QIN Cuihong CHEN Liu YAN Jing CHENG Can CUI Hanwen HU Wenyu LIU Xizhe YAN Huaxuan WANG Xiaodong LIU Guannan GENG Yu LEI Dabo GUAN Kebin HE Qiang ZHANG Department of earth System Science Ministry of Education Key Laboratory for Earth System ModelingInstitute for Global Change StudiesTsinghua UniversityBeijing100084China State Key Joint Laboratory of environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Chinese Academy of environmental Planning Beijing100041China institute for Carbon Neutrality Tsinghua UniversityBeijing100084China

CO_(2)emission inventory provides fundamental data for climate research and emission ***,most global CO_(2)emission inventories were developed with energy statistics from International Energy Agency(IEA)and were available at country level with limited source ***,as the first step toward a high-resolution and dynamic updated global CO_(2)emission database,we developed a data-driven approach to construct seamless and highly-resolved energy consumption data cubes for 208 countries/territories,797 sub-country administrative divisions in 29 countries,42 fuel types,and 52 sectors,with the fusion of activity data from 24 international statistics and 65 regional/local *** CO_(2)emissions from fossil fuel combustion and cement production in 1.70–2021.were then estimated with highly-resolved source category(1.484 of total)and sub-country information(797 of total).Specifically,73%of global CO_(2)emissions in 2021.were estimated with sub-country information,providing considerably improved spatial resolution for global CO_(2)emission *** the support of detailed information,the dynamics of global CO_(2)emissions across sectors and fuel types were presented,representing the evolution of global economy and progress of climate *** differences of sectoral contribution were found across sub-country administrative divisions within a given country,revealing the uneven distribution of energy and economic structure among different *** estimates were generally consistent with existing databases at aggregated level for global total or large emitters,while large discrepancies were observed for middle and small *** database,named the Multiresolution Emission Inventory model for Climate and air pollution research(MEIC)is publicly available through http://*** with highly-resolved information and timely update,which provides an independent carbon emission accounting data source for climate rese

关键词： CO_(2)emissions Data-driven approach Highly-resolved source category Sub-country information

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：