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Melting geodynamics reveals a subduction origin for the Purang ophiolite,Tibet,China

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Acta Geochimica 2024年第4期43卷 754-773页

作者： Tao Ruan Zhong-Jie Bai Wei-Guang Zhu Shi-Ji Zheng State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The debate regarding whether the Yarlung-Zangbo ophiolite(YZO)on the south of the Qinghai-Tibet Plateau,formed in a mid-ocean ridge(MOR)or a supra-subduction zone(SSZ)setting has remained *** we present petrological,mineralogical,and geochemical data associated with modeling melting geodynamics of the mantle peridotites from the Purang ophiolite in the western segment of the Yarlung-Zangbo Suture Zone(YZSZ)to explore its tectonic *** Purang lherzolites are characterized by the protogranular texture and have abyssal-peridotite-like mineral compositions,including low Cr^(#)(20-30)and TiO_(2) contents(environment for these *** is therefore concluded that the Purang ophiolite has experienced a transformat

关键词： Melting geodynamics SSZ peridotites MOR peridotites Clinopyroxene Purang ophiolite

Disentangling the factors that contribute to variation in forest biomass increments in the mid-subtropical forests of China

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Journal of Forestry Research 2016年第4期27卷 919-930页

作者： Yin Ren Shanshan Chen Xiaohua Wei Weimin Xi Yunjian Luo Xiaodong Song Shudi Zuo Yusheng Yang Key Laboratory of Urban environment and Health Key Laboratory of Urban Metabolism of Xiamen Institute of Urban Environment Chinese Academy of Sciences Ningbo Urban environment Observation and Research Station-NUEORS Chinese Academy of Sciences Department of Earth and environmental Sciences University of British Columbia Okanagan Campus Department of Biological and Health Sciences Texas A&M University-Kingsville College of environment and Natural resources Zhejiang University Key Laboratory of Humid Subtropical Eco-Geographical Processes Ministry of Education Fujian Normal University

Mid-subtropical forests are the main vegetation type of global terrestrial biomes, and are critical for maintaining the global carbon balance. However, estimates of forest biomass increment in mid-subtropical forests remain highly uncertain. It is critically important to determine the relative importance of different biotic and abiotic factors between plants and soil, particularly with respect to their influence on plant regrowth. Consequently,it is necessary to quantitatively characterize the dynamicspatiotemporal distribution of forest carbon sinks at a regional scale. This study used a large, long-term dataset in a boosted regression tree（BRT） model to determine the major components that quantitatively control forest biomass increments in a mid-subtropical forested region（Wuyishan national Nature Reserve, China）. Long-term,stand-level data were used to derive the forest biomass increment, with the BRT model being applied to quantify the relative contributions of various biotic and abiotic variables to forest biomass increment. Our data show that total biomass（t） increased from 4.62 9 106 to 5.30 9 106 t between 1988 and 2010, and that the mean biomass increased from 80.19 ± 0.39 t ha-1（mean ± standard error） to 94.33 ± 0.41 t ha-1in the study region. The major factors that controlled biomass（in decreasing order of importance） were the stand, topography, and soil. Stand density was initially the most important stand factor, while elevation was the most important topographic factor. Soil factors were important for forest biomass increment but have a much weaker influence compared to the other two controlling factors. These results provide baseline information about the practical utility of spatial interpolationmethods for mapping forest biomass increments at regional scales.

关键词： biomass forests subtropical stand abiotic Castanopsis increment quantitatively uncertain accounted

Feedback and contribution of vegetation, air temperature and precipitation to land surface temperature in the Yangtze River Basin considering statistical analysis

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International Journal of Digital Earth 2023年第1期16卷 2941-2961页

作者： Jinlian Liu Xinyao Zhou Hanya Tang Fengqin Yan Shiwei Liu Xuguang Tang Zhi Ding Ke Jiang Pujia Yu Chongqing Jinfo Mountain Karst Ecosystem national Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqingPeople’s Republic of China State Key Laboratory of resources and environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China Chongqing Key Laboratory of Karst environment School of Geographical SciencesSouthwest UniversityChongqingPeople’s Republic of China

Land surface temperature(LST),especially day-night LST difference(LSTd-LSTn),is a key variable for the stability of terrestrial ecosystems,affected by vegetation and climate *** the contribution and feedback of vegetation and climate to LST changes is critical to developing mitigation *** on LST,Normalized vegetation index(NDVI),land use(LU),air temperature(AT)and precipitation(Pre)from 2003 to 2021,partial correlation was used to analyze the response of LST to vegetation and *** feedback and contribution of both to LST were further quantifed by using spatial linear relationships and partial derivatives *** results showed that both interannual LST(LSTy)and LSTd-LSTn responded negatively to vegetation,and vegetation had a negative feedback effect in areas with significantly *** was also a major contributor to the decline of *** the advantage of positive partial correlation area of 94.99%,AT became the main driving factor and contributor to LSTy change *** contributed negatively to both LSTy and LSTd-LSTn,with contributions of-0.004℃/y and-0.022℃/y,*** played a decisive role in LST warming of YRB,which was partially mitigated by vegetation and *** present research contributed'to,the,detection,of LST changes and improved understanding of the driving mechanism.

关键词： Land surface temperature vegetation dynamics climate change land use contribution feedback

Water resources response and prediction under climate change in Tao'er River Basin,Northeast China

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Journal of Mountain Science 2021年第10期18卷 2635-2645页

作者： SUN Jia-qi LI Hong-yan WANG Xiao-jun SHAHID Sliamsuddin College of Hydrology and Water resources Hohai UniversityNanjing 210098China Key Laboratory of Groundwater resources and environment Ministry of EducationJilin UniversityChangchun 130021China State Key Laboratory of Hydrology-Water resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China Research Center for Climate Change Ministry of Water ResourcesNanjing 210029China School of Civil Engineering Faculty of EngineeringUniversiti Teknologi Malaysia(UTM)81310Johor BahruMalaysia

Climate change has significantly affected hydrological processes and increased the frequency and severity of water shortage,droughts and floods in northeast China.A study has been conducted to quantify the influence of climate change on the hydrologic process in the Tao’er River Basin(TRB),one of the most prominent regions in northeast China for water *** Soil and Water Assessment Tool(SWAT)model was calibrated and validated with observed land use and hydro-climatic data and then employed for runoff simulations at upper,middle and lower reaches of the river basin for different climate change *** results showed that a gradual increase in temperature and decrease in annual precipitation in the basin was projected for the period 2020-2050 for both representative concentration pathways(RCP)4.5 and 8.5 *** climate changes would cause a decrease in annual average runoff at basin outlet by 12 and 23 million m^(3) for RCP4.5 and 8.5,*** future runoff in the upstream and midstream of the basin during 2020-2050 would be-10.8% and-12.1% lower than the observed runoff compared to the base period for RCP4.5,while those would be-5.3% and-10.7%lower for *** future runoff will decrease at three hydrology stations for the assumed future climate *** results can help us understand the future temperature and precipitation trends and the hydrological cycle process under different climate change scenarios,and provide the basis for the rational allocation and management of water resources under the influence of future climate change in the TRB.

关键词： Hydrological process simulation Climate change Climate scenario model SWAT model Tao’er River Basin

Distribution patterns of planted-shrubs of different restoration ages in artificial sand-fixing regions in the southeastern Tengger Desert

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Research in Cold and Arid Regions 2020年第2期12卷 119-124页

作者： MeiLing Liu Ning Chen RuiQing Zhu Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Shapotou Desert Research&Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China School of Life Science Lanzhou UniversityLanzhouGansu 730000China Key Laboratory of Microbial resources Exploitation and Application of Gansu Province Institute of BiologyGansu Academy of SciencesLanzhouGansu 730000China

Plant density and spatial distribution in artificial vegetation is obviously initialized at the planting stage. Plant dynamics and spatial pattern may change over time as the result of interactions between individual plants and habitats, but whether it’s applied for desert shrubs in artificial sand-fixing regions remains unknown. Here we examined changes in plant density and distribution patterns of three shrubs(Artemisia ordosica Krasch, Caragana korshinskii Kom, and Hedysarum scoparium Fisch.) in different regions, which have been restored for 27, 32 and 50 years(R27, R32, R50), respectively. The vegetation analysis shows that A. ordosica was the dominated species across the 3 restoration regions. The density of A. ordosica and H. scoparium show a significant increase from R27 to R32, then decreased in R50. The density of C. korshinskii was low in R32 and R50, lower in R27. The variance-to-mean ratio(VMR) was used to characterize spatial distribution patterns to fit the observed densities of the three shrubs by frequency. A. ordosica and C. korshinskii both show significantly clumped distributions in three restoration regions. H. scoparium show a uniform distribution in R27 and R50, but a clumped distribution in R32. These results show that A. ordosica seems to be more adaptable in revegetated desert areas compared to C. korshinskii and H. scoparium. Pattern analysis suggests a successive replacement of C. korshinskii, which had low proportions of survived shrubs, by the dominant A. ordosica. This study contributes to the understanding of the distribution patterns of shrubs plants in revegetation projects in arid desert areas.

关键词： restoration shrubs density spatial pattern

Mechanism of rhodium(Ⅲ)-catalyzed formal C(sp^3)-H activation/spiroannulation of a-arylidene pyrazolones with alkynes:A computational study

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Chinese Chemical Letters 2018年第9期29卷 1355-1358页

作者： Hongyan Zou Zhong-Liang Wang Yang Cao Genping Huang Tianjin Key Laboratory of Water resources and environment Tianjin Normal University Tianjin 300387 China Department of Chemistry School of Science Tianjin University Tianjin 300072 China institute of New Energy Shenzhen 518031 China

The rhodium-catalyzed formal C（sp^3）-H activation/spiroannulation of α-arylidene pyrazolones with alkynes was investigated by means of density functional theory calculations. The calculations indicate that the spiroannulation through the proposed C-C reductive elimination is kinetically unfeasible, Instead, the C-C coupling from the eight-membered rhodacycle was proposed to account for the experimental results. The overall catalytic cycle consists of six steps：（1） the keto-enol isomerization; （2） the O-H deprotonation, （3） the C（sp^2）-H bond cleavage; （4） the migratory insertion of alkyne into the Rh-C bond; （5） the C-C coupling and （6） the regeneration of the active catalyst.

关键词： Rhodium Spiroannulation C-H activation Reaction mechanism DFT calculations

Analysis of precipitation characteristics of South and North China based on the power-law tail exponents

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Chinese Physics B 2008年第7期17卷 2745-2752页

作者：封国林龚志强支蓉章大全 Department of Physics Yangzhou University Key Laboratory of Regional Climate-environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences Laboratory for Climate Studies National Climate CenterChina Meteorological Administration

Precipitation sequence is a typical nonlinear and chaotic observational series, and studies on precipitation forecasts are restricted to the use of traditional linear statistical methods, especially when analysing the regional characteristics of precipitation. In the context of 20 stations＇ daily precipitation series （from 1956 to 2000） in South China （SC） and North China （NC）, we divide each precipitation series into many self-stationary segments by using the heuristic segmentation algorithm （briefly BG algorithm）. For each station＇s precipitation series, we calculate the exponent of power-law tall （EPT） of the cumulative probability distribution of segments with a length larger than l for precipitation and temperature series. Our results show that the power-law decay of the cumulative probability distribution of stationary segments might be a common attribution for precipitation and other nonstationary time series; the EPT somewhat indicates the precipitation duration and its spatial distribution that might be different from area to area. The EPT in NC is larger than in SC; Meanwhile, EPT might be another effective way to study the abrupt changes in nonlinear and nonstationary time series.

关键词： the power-law exponents precipitation durative abrupt precipitation change

Harmful algal bloom-forming dinofl agellate Prorocentrum donghaiense inhibits the growth and photosynthesis of seaweed Sargassum fusiformis embryos

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Journal of Oceanology and Limnology 2021年第6期39卷 2237-2251页

作者： Caixia WANG Min WANG Binbin CHEN Wenli QIN Lidong LIN Chuanjun DAI Hengguo YU Renhui LI Min ZHAO Zengling MA Zhejiang Provincial Key Laboratory for Subtropical Water environment and Marine Biological resources Protection Wenzhou UniversityWenzhou 325035China national and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution Wenzhou UniversityWenzhou 325035China Dongtou Fisheries Science and Technology Research institute Wenzhou 325700China

Harmful algal bloom(HAB)is an ecological disaster to local *** present,its impact on macrophytes has not been well *** this study,we cultivated sexually propagated embryos of S argassum fusiformis-an edible seaweed-in Prorocentrum donghaiense suspensions at different cell densities(0,0.50×10^(5),0.75×10^(5),1.00×10^(5),and 1.50×10^(5) cells/mL)for 10 days,during which growth and photosynthetic activities of the embryos were determined,and a monocultivation was set up for *** show that the relative growth rate and photosynthetic activities of the embryos co-cultivated with *** were inhibited mostly and significantly in the cell densities of 0.75×10^(5),1.00×10^(5),and 1.50×10^(5) cells/mL,and the inhibitory effects increased in overall with increased cell *** maximum relative electron transport rates(rETR max)and apparent photosynthetic efficiency(a)of co-cultivated embryos were all significantly lower than monocultivation ones on the 10 th ***,the photosynthetic activity detected by chlorophyll-a fluorescence transient(i.e.,OJIP),the electron transport among electron transfer accepters of PSII(photosystem II)and that from PSII to PSI(photosystem I)was restricted,which is probably responsible for the decreases of rETR max andain the co-cultivated *** addition,parts of the photosynthetic reaction centers of PSII in the co-cultivated embryos were ***,*** bloom could restrain the development and photosynthetic activities of *** embryos,reduce the seedlings stock,and eventually hinder the development of *** production industry.

关键词： embryo JIP-test photosynthesis Prorocentrum donghaiense Sargassum fusiformis harmful algal bloom

Contribution of Mass Elevation Effect to the Altitudinal Distribution of Global Treelines

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Journal of Mountain Science 2015年第2期12卷 289-297页

作者： ZHAO Fang ZHANG Bai-ping ZHANG Shuo QI Wen-wen HE Wen-hui WANG Jing YAO Yong-hui State Key Laboratory of Resource and environment Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application

Alpine treeline, as a prominent ecological boundary between forested mountain slopes and alpine meadow/shrub, is highly complex in altitudinal distribution and sensitive to warming climate. Great efforts have been made to explore their distribution patterns and ecological mechanisms that determine these patterns for more than 100 years, and quite a number of geographical and ecophysiological models have been developed to correlate treeline altitude with latitude or a latitude related temperature. However,on a global scale, all of these models have great difficulties to accurately predict treeline elevation due to the extreme diversity of treeline site *** of the major reasons is that "mass elevation effect"(MEE) has not been quantified globally and related with global treeline elevations although it has been observed and its effect on treeline elevations in the Eurasian continent and Northern Hemisphere recognized. In this study, we collected and compiled a total of 594 treeline sites all over the world from literatures, and explored how MEE affects globaltreeline elevation by developing a ternary linear regression model with intra-mountain base elevation(IMBE, as a proxy of MEE), latitude and continentality as independent variables. The results indicated that IMBE, latitude and continentality together could explain 92% of global treeline elevation variability, and that IMBE contributes the most(52.2%), latitude the second(40%) and continentality the least(7.8%) to the altitudinal distribution of global treelines. In the Northern Hemisphere, the three factors' contributions amount to 50.4%, 45.9% and 3.7% respectively; in the south hemisphere, their contributions are 38.3%, 53%, and 8.7%, respectively. This indicates that MEE, virtually the heating effect of macro-landforms, is actually the most significant factor for the altitudinal distribution of treelines across the globe, and that latitude is relatively more significant for treeline elevation in the

关键词： Alpine treeline Intra-mountain base elevation Multiple regression analysis Geographicalfactor Continentality Contribution rate