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Reconstructing forest and grassland cover changes in China over the past millennium

Science China Earth sciences 2025年第1期68卷 94-110页

作者： Fanneng HE Fan YANG Yafei WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Research Institute of Yellow River Civilization and Sustainable Development Henan University University of Chinese Academy of sciences

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments. However, because of limitations in historical data, quantitative estimations and spatially gridded reconstructions of these changes remain challenging, necessitating further methodological exploration. This study focused on China's present-day land area over the past millennium, objectively capturing the characteristics and drivers of forest and grassland cover changes. On this basis, using the forest transition theory and the space-for-time substitution method, we depicted the historical deforestation process as an inverted “S” curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics. Subsequently, a gridded forest allocation model was established on the basis of deforestation tendencies. For the grassland cover, we implemented regionspecific methods, such as the cropland area deduction method and the habitat constraint method, to quantitatively reconstruct historical changes. Consequently, we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover. The results indicated the following.(1) The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium. These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2) The data indicated that China's forest area generally decreased over the past millennium, characterized by a “decrease-then-increase” pattern. The forest area experienced three distinct phases: a slow decline(AD 1000

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and natural Medicines (Chinese Academy of sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

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Spatio-temporal patterns and climatic drivers of spring phenology in eight forest communities across the north-south transitional zone of China

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Journal of Geographical sciences 2025年第1期35卷 17-38页

作者： ZHU Wenbin LU Yu Institute of Geographic sciences and natural Resources Research CAS School of Geographical Science Nanjing University of Information Science & Technology

The Qinba Mountains are climatically and ecologically recognized as the northsouth transitional zone of *** of its phenology is critical for comprehending the response of vegetation to climatic *** retrieved the start of spring phenology （SOS）of eight forest communities from the MODIS products and adopted it as an indicator for spring *** analysis,partial correlation analysis,and Geo Detector were employed to reveal the spatio-temporal patterns and climatic drivers of *** results indicated that the SOS presented an advance trend from 2001 to 2020,with a mean rate of–0.473 d yr–*** SOS of most forests correlated negatively with air temperature （TEMP） and positively with precipitation （PRE）,suggesting that rising TEMP and increasing PRE in spring would forward and delay SOS,*** dominant factors influencing the sensitivity of SOS to climatic variables were altitude,forest type,and latitude,while the effects of slope and aspect were relatively *** response of SOS to climatic factors varied significantly in space and among forest communities,partly due to the influence of altitude,slope,and aspect.

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Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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Science China Earth sciences 2025年第1期68卷 111-127页

作者： Zhi-Wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG Qing XIA Xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Traffic & Transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service

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Pyrite Geochemistry and S-Hg Isotopes Reveal the Ore Genesis of the Hydrothermal Vein-type Cuiluan Ag-Pb-Zn Deposit in NE China

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Journal of Earth Science 2025年

作者： Lidong Zhang Changzhou Deng Yao Tang Xinran Ni Bizheng Yang Shanshan Liang Weipeng Liu Jishuang Ding Xiaohui Zeng Heilongjiang Institute of natural Resources Survey State Key Laboratory of Ore Deposit Geochemistry， Institute of Geochemistry， Chinese Academy of sciences College of Earth and Planetary sciences， Chengdu University of Technology

The Xing'an-Mongolian orogenic belt is an important Ag-Pb-Zn metallogenic province in China. The study on the genesis of the newly discovered Cuiluan hydrothermal vein-type Ag-Pb-Zn deposit located in the Lesser Xing'an Range， within the eastern of Xing'an-Mongolian orogenic belt， is pivotal in understanding the metallogenic mechanism and regularity of Ag-Pb-Zn deposits in this region. This study utilizes pyrite trace elements and sulfur isotopic geochemistry， and mercury isotope of rocks and ores to constrain the genesis of the Cuiluan deposit. Pyrite geochemical data show that Ag exists in the form of galena inclusions (Ag++(Bi3+， Sb3+) ? Pb2+) in the polymetallic sulfide stage， and independent Ag-bearing minerals （matildite and gustavite） precipitate during the main mineralization stage. The small varied δ34S values （3.24‰ - 4.94‰） of pyrites from four hydrothermal stages are within the range of magmatic S isotopes， indicating that the ore-forming fluid of the Cuiluan deposit mainly originated from the magma. The Δ199Hg values of the ores are close to 0‰， which are consistent with the Δ199Hg values of mantle， further indicating that the ore-forming materials came from the lithospheric mantle. Combined with the regional tectonic evolution， we conclude that the plate subduction of Paleo-oceans in NE China triggered the partial melting of metasomatized mantle. The mantle-derived magma rose along the deep fractures and evolved ore-forming fluids， and finally caused the formation of Cuiluan quartz vein-type Ag-Pb-Zn deposit in the shallow crust. Accompany with previous documents， we infer that the fractures in the large-scale “Granite Sea” in the Lesser Xing'an Range may have significant potential for vein-type Ag-Pb-Zn exploration.

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First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

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Science China Earth sciences 2025年第1期68卷 1-10页

作者： Yongping WANG Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU Ze-Jun HU Bin LI Key Laboratory for Polar Science Ministry of Natural Resources Polar Research Institute of China Institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology School of Earth and Space sciences University of Science and Technology of China School of Electronic Information Wuhan University

The Medium-energy Electron Spectrometers(MES) is a space-borne instrument onboard Macao Science Satellite-1(MSS-1) dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development, including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch, all within the range of 1.5

关键词： Lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao Science Satellite-1

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Research on the deformation mechanism of flexural toppling deep-seated landslides based on large centrifuge physical model testing: A case study of the Genie landslide in the Tibetan Plateau

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Journal of Earth Science 2025年

作者： Shichao Cao Xiujun Dong Changbao Guo Ruian Wu Zhihua Yang Guang Zheng Xiaoqiang Zhu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection， Chengdu University of Technology Institute of Geomechanics， Chinese Academy of Geological sciences Key Laboratory of Active Tectonics and Geological Safety， Ministry of natural Resources

Flexural toppling is a widespread failure mode in natural and excavated anti-inclined rock slopes of the eastern Tibetan Plateau， which can further evolve into large deep-seated landslides， posing significant threats to the construction and operation of important infrastructure. In this study， we took the large deep-seated Genie landslide as a case study and established a centrifuge physical model to analyze the deformation mechanism and evolutionary process of flexural toppling deep-seated landslides under the effect of gravity. The results indicate that the geomechanical mode of landslide instability is characterized by flexural toppling-shearing-sliding， with the deformation process could be divided into three stages: initial slow deformation stage marked by crack generation， rapid deformation stage characterized by the expansion and fracturing of cracks， and a low-speed deformation stage characterized by creep. Notably， the sliding surfaces do not adhere strictly to predefined bending zones but develop cracks along the bending parts， which gradually expand and penetrate deeper， eventually forming multiple potential sliding surfaces. The analysis of the entire process deformation evolution of flexural toppling deep-seated landslides suggests that the rapid deformation stage is the optimal time to take action for landslide prevention and control. The study demonstrates that the shear strength also plays a key factor in the evolution of flexural toppling. The research reveals the deformation mechanism and evolutionary process of large deep-seated landslides in deep-cut canyon areas， providing valuable reference for the prediction， assessment， and prevention of such slopes and landslides.

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Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-Bo Jin Cong-Feng Qiao Yue-Liang Wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

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Engendered nanoparticles for treatment of brain tumors

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Oncology Research 2025年第1期33卷 15-26页

作者： SOROUSH SOLEYMANI MOHAMMAD DOROUDIAN MAHDIEH SOEZI ALI BELADI KIARASH ASGARI ASO MOBARAKSHAHI ARYANA AGHAEIPOUR RONAN MACLOUGHLIN Department of Cell and Molecular Biology School of Biological SciencesUniversity of LeicesterLeicesterLE17RHUK Department of Cell and Molecular Biology Faculty of Biological SciencesKharazmi UniversityTehran15719-14911Iran Cancer Epidemiology Research Center Aja University of Medical SciencesTehran14117-18541Iran Medical Biotechnology Research Center Aja University of Medical SciencesTehran14117-18541Iran Department of Life sciences Faculty of Natural SciencesImperial College LondonLondonSW72AZUK School of Pharmacy and Biomolecular sciences Royal College of Surgeons in Ireland(RCSI)DublinD02 YN77Ireland Research and Development Science and Emerging TechnologiesAerogen Ltd.Galway Business ParkGalwayH91 HE94Ireland School of Pharmacy and Pharmaceutical sciences Trinity CollegeDublinD02 PN40Ireland

Brain metastasis and primary glioblastoma multiforme represent the most common and lethal malignant brain *** median survival time is typically less than a year after *** of the major challenges in treating these cancers is the efficiency of the transport of drugs to the central nervous *** blood-brain barrier is cooperating with advanced stages of *** blood-brain barrier poses a significant challenge to delivering systemic medications to brain *** delivery systems have emerged as promising tools for effectively crossing this ***,the development of smart nanoparticles brings new hope for cancer diagnosis and *** nanoparticles improve drug delivery efficiency,allowing for the creation of targeted and stimuli-responsive delivery *** review highlights recent advancements in nanoparticle and smart nanoparticle technologies for brain cancer treatment,exploring the range of nanoparticles under development,their applications,targeting strategies,and the latest progress in enhancing transport across the blood-brain *** also addresses the ongoing challenges and potential benefits of these innovative approaches.

关键词： Nanoparticles Smart nanoparticles Stimuli responsive nanoparticles Targeted nanoparticles Blood-brain barrier(BBB) Brain cancer

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Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China Earth sciences 2025年第1期68卷 226-236页

作者： Yumin AI Massimo CHIARADIA Chao WU Huayong CHEN Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of sciences Department of Earth sciences University of Geneva Guangdong Provincial Key Laboratory of Mineral Physics and Materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（<20 km）, which are significantly influenced by subducted slab materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： Magma evolution V/Sc systematics Magnetite Oxygen fugacity Porphyry copper deposits

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