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Hyperosmolality tolerance of freshwater largemouth bass Micropterus salmoides to brackish in early ontogenetic stages of eggs,embryos,and yolk-sac larvae

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Journal of Oceanology and Limnology 2025年第1期43卷 286-298页

作者： Du LUO Dingtian YANG South china Sea institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China Pearl River Fisheries research institute Chinese Academy of Fishery SciencesGuangzhou 510380China University of Chinese academy of sciences Beijing 100049China

Salinity is recognized as a pivotal factor limiting the migration of freshwater fish to brackish *** largemouth bass(LMB,Micropterus salmoides),a globally translocated freshwater fish,exhibits estuarine distribution,yet its hyperosmoregulatory capacity during early ontogenetic stages remains inadequately *** investigate the impact of freshwater salinization,a series of experiments were conducted in Guangzhou and Foshan,*** reveal that freshwater-activated mature eggs and naturally fertilized oocytes maintained nearly identical osmotic homeostasis,with diameters of 1.38±0.07 mm and 1.37±0.05 mm,***,both exhibited peak water excretion at a salinity of ***,a reduction in water permeability was observed in hyperosmotic *** hatching rates increased from 27.5%±14.4%in the 1.0 group to 75.1%±12.0%in the 6.0 group under fluctuating temperature ***-sac LMB larvae consistently reduced survival time from 12.5 d at 1.0 to 50.7±2.1 min at salinity of ***,more developed larvae also experienced a decrease in survival *** regression models fitting lethal time with salinity indicated a sharp decrease between 10.0 and *** findings offer practical insights for predicting distribution patterns and enhancing aquaculture technology for ***,they may contribute theoretically to the broader understanding of the osmoregulatory mechanisms of freshwater fish.

关键词： osmotic homeostasis acute toxicity median lethal time hatching rate dose-response model

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

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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 ResearchChinese Academy of SciencesBeijing100101China Key research institute of Yellow River Civilization and Sustainable Development Henan UniversityKaifeng475001China University of Chinese academy of sciences Beijing100049China

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 ***,because of limitations in historical data,quantitative estimations and spatially gridded reconstructions of these changes remain challenging,necessitating further methodological *** study focused on china's present-day land area over the past millennium,objectively capturing the characteristics and drivers of forest and grassland cover *** 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 ***,a gridded forest allocation model was established on the basis of deforestation *** the grassland cover,we implemented regionspecific methods,such as the cropland area deduction method and the habitat constraint method,to quantitatively reconstruct historical ***,we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland *** 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 *** 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”*** forest area experienced three distinct phases:a slow decline(AD 1000–1650),a rapid decline(AD 16

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

Priority sources identification and risks assessment of heavy metal(loid)s in agricultural soils of a typical antimony mining watershed

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Journal of Environmental sciences 2025年第1期147卷 153-164页

作者： Lianhua Liu You Li Xiang Gu Roberto Xavier Supe Tulcan Lingling Yan Chunye Lin Junting Pan institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of Environment Beijing Normal UniversityBeijing 100875China Yiyang academy of Agricultural sciences Yiyang 413099China institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China

Heavy metal(loid)(HM)pollution in agricultural soils has become an environmental concern in antimony(Sb)mining ***,priority pollution sources identification and deep understanding of environmental risks of HMs face great challenges due to multiple and complex pollution sources ***,an integrated approach was conducted to distinguish pollution sources and assess human health risk(HHR)and ecological risk(ER)in a typical Sb mining watershed in Southern *** approach combines absolute principal component score-multiple linear regression(APCS-MLR)and positivematrix factorization(PMF)models with ER and HHR *** pollution sources were distinguished for both models,and APCS-MLR model was more accurate and *** HM concentration source was natural source(39.1%),followed by industrial and agricultural activities(23.0%),unknown sources(21.5%)and Sb mining and smelting activities(16.4%).Although natural source contributed the most to HM concentrations,it did not pose a significant *** and agricultural activities predominantly contributed to ER,and attention should be paid to Cd and *** mining and smelting activities were primary anthropogenic sources of HHR,particularly Sb and As *** ER and HHR assessments,Sb mining and smelting,and industrial and agricultural activities are critical sources,causing serious ecological and health *** study showed the advantages of multiple receptor model application in obtaining reliable source identification and providing better source-oriented risk *** pollution management,such as regulating mining and smelting and implementing soil remediation in polluted agricultural soils,is strongly recommended for protecting ecosystems and humans.

关键词： Antimony Heavy metal(loid) Risk assessment Pollution sources Mining and smelting

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science china Chemistry 2025年第1期68卷 134-151页

作者： Jing Niu Shutao Xu Yingxu Wei Zhongmin Liu National Engineering research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese academy of sciences Beijing 100049China

The methanol-to-olefins(MTO)reaction offers an alternative pathway for the production of low-carbon olefins from non-oil *** research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in ***-situ solid-state nuclear magnetic resonance(ss NMR)spectroscopy has emerged as a pivotal tool,offering crucial insights into key species under real-time operando ***,the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ^(13)C MAS NMR and 2D correlation ***,recent technological advancements in hyperpolarization(HP)methods,including HP^(129)Xe NMR and dynamic nuclear polarization(DNP),have significantly improved the sensitivity of ssNMR,enabling detailed structural and kinetic analysis as well as the detection of trace *** this feature article,we summarized recent advancements in(in-situ)ssNMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest *** theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts,thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism

Chemical weathering in Manas River Basin:Driven by sulfuric acid or carbonic acid?

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Acta Geochimica 2025年第1期44卷 59-85页

作者： Jiaxin Zhang Bingqi Zhu Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina University of Chinese academy of sciences BeijingChina

Carbonic acid produced by the dissolution of atmospheric and soil CO_(2)in water is usually the most dominant catalyst for chemical weathering,but a sulfuric aciddriven phenomenon,different from usual,was found in the orogenic belt watersheds dominated by silicate *** study,rooted in comprehensive field investigations in the Manas River Basin(MRB)north of the Tianshan Mountains,delves into the mechanisms and impacts of sulfuric and carbonic acid as catalysts driving diff erent types of chemical weathering in the Central Asian Orogenic *** analyses elucidate that carbonate weathering constitutes 52.4%of the total chemical weathering,while silicate and evaporite account for 18.6%and 25.3%,respectively,with anthropogenic activities and atmospheric precipitation having little eff *** estimated total chemical weathering rate in MRB is approximately 0.075×10^(6)mol/km^(2)/*** findings further suggest that,preceding carbonate precipitation(<10^(4)year),chemical weathering can absorb CO_(2).Subsequently,and following carbonate precipitation(10^(4)-10^(7)year),it will release CO_(2).The release significantly surpasses the global average CO_(2)consumption,contributing to a noteworthy climate *** study underscores the distinctive weathering mechanisms,wherein sulfuric acid emerges as the predominant *** quantity of sulfuric acid as a catalyst is approximately three times that of carbonic *** acid-driven carbonate rock weathering(SCW)is identified as the sole chemical weathering type with a net CO_(2)release eff *** CO_(2)release flux(5176 mol/km^(2)/year)is roughly 2.5 times the CO_(2)absorption by Ca-Mg silicate weathering,highlighting the pivotal role of chemical weathering in sourcing atmospheric CO_(2)over the timescales of carbonate precipitation and sulfate ***,this study posits that catalyst and transport limitations are the most plausible critical factors in *** interplay between s

关键词： Catchment chemical weathering Mid-latitude orogenic belt Sulﬁde oxidation Manas River Basin

Distribution and mapping of temperate savanna in the sandy lands of eastern china

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Science china Earth sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG Xin TIAN Qi LU institute of Ecological Conservation and Restoration Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China institute of Desertification Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China institute of Great Green Wall Bayan Nur015200China Satellite Application Centre for Ecology and Environment MEEBeijing100094China institute of Microelectronics Chinese Academy of SciencesBeijing100029China Aerospace Information research institute Chinese Academy of SciencesBeijing100094China institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in china cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution(VHR)unmanned aerial vehicle(UAV)and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover(FWVC)and fractional herbaceous vegetation cover(FHVC)in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern china was mapped to a unit area of 0.5 *** root-mean-square error(RMSE)values for the FWVC and FHVC models were 10.69%and 11.67%,and the R^(2)values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern china were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10^(6)*** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy Land a

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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Late spring-early summer drought and soil properties jointly modulate two pine species?decline and climatic sensitivity in temperate Northern china

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Forest Ecosystems 2025年第1期12卷 146-158页

作者： Yuheng Li Zhaofei Fan Lihong Xu Xiao Zhang Zhongjie Shi Xiaohui Yang Wei Xiong Ling Cong Semyun Kwon Leilei Pan f Hanzhi Li Shuo Wen Xiaoyan Shang institute of Geographic sciences and Natural Resources research Chinese Academy of SciencesBeijing100101China research institute of Ecological Conservation and Restoration Chinese Academy of ForestryBeijing100091China research institute of Desertification Studies Chinese Academy of ForestryBeijing100091China College of Forestry Wildlife and EnvironmentAuburn UniversityAL36849United States Ecology and Nature Conservation institute Chinese Academy of ForestryBeijing100091China institute of Ecological Restoration Kongju National UniversityChungcheongnam-do32439Republic of Korea University of Chinese academy of sciences Beijing100049China

Increasing temperatures and severe droughts threaten forest vitality *** of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts on the growth of tree species,likely driven by local climatic aridity,climate trends,edaphic conditions,and the climatic adaption of tree *** ability of tree species to cope with changing climate and the effects of environmental variables on growth trends and growth-climate relationships across diverse bioclimatic regions are still poorly understood for many *** study investigated radial growth trends,interannual growth variability,and growth-climate sensitivity of two dominant tree species,Pinus tabulaeformis(PT)and Pinus sylvestris ***(PS),across a broad climatic gradient with a variety of soil properties in temperate Northern *** a network of 83 tree ring chronologies(54 for PT and 29 for PS)from 1971 to 2010,we documented that both species maintained constant growth trends at wet sites,while both displayed rapid declines at dry *** reported the species-specific drivers of spatial heterogeneity in growth trends,interannual growth variability,and growth-climate *** climatic variables and soil properties were identified as the most critical factors affecting the growth trends and growth-climate ***,climatic variables play more essential roles than soil properties in determining the spatial heterogeneity of the growth-climate *** clay content and higher soil nutrient regimes can exacerbate the moisture-related susceptibility of tree *** findings highlight that soil properties emerged as important modulating factors to predict the drought vulnerability of forests in addition to climatic *** the continued climate warmingdrying trend in the future,both pines will face a more severe growth decline and increase in drought vulnerability at dri

关键词： Tree rings Climate sensitivity Growth decline Global warming Drought Soil property

Predicting the efficiency of arsenic immobilization in soils by biochar using machine learning

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Journal of Environmental sciences 2025年第1期147卷 259-267页

作者： Jin-Man Cao Yu-Qian Liu Yan-Qing Liu Shu-Dan Xue Hai-Hong Xiong Chong-Lin Xu Qi Xu Gui-Lan Duan State Key Lab of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Henan institute of Advanced Technology Zhengzhou UniversityZhengzhou 450052China University of Chinese academy of sciences Beijing 100049China

Arsenic(As)pollution in soils is a pervasive environmental *** immobilization offers a promising solution for addressing soil As *** efficiency of biochar in immobilizing As in soils primarily hinges on the characteristics of both the soil and the ***,the influence of a specific property on As immobilization varies among different studies,and the development and application of arsenic passivation materials based on biochar often rely on empirical *** enhance immobilization efficiency and reduce labor and time costs,a machine learning(ML)model was employed to predict As immobilization efficiency before biochar *** this study,we collected a dataset comprising 182 data points on As immobilization efficiency from 17 publications to construct three ML *** results demonstrated that the random forest(RF)model outperformed gradient boost regression tree and support vector regression models in predictive *** importance analysis and partial dependence plots based on the RF model were conducted to identify the most crucial factors influencing As *** findings highlighted the significant roles of biochar application time and biochar pH in As immobilization efficiency in ***,the study revealed that Fe-modified biochar exhibited a substantial improvement in As *** insights can facilitate targeted biochar property design and optimization of biochar application conditions to enhance As immobilization efficiency.

关键词： Biochar Arsenic immobilization Soil Machine learning

How sediment dredging alters phosphorus dynamics in a lowland rural river?

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Journal of Environmental sciences 2025年第1期147卷 189-199页

作者： Qimou Zhang Jiacong Huang Yulai Ji Jing Zhang Shuai Zhang Junfeng Gao Key Laboratory of Watershed Geographic sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese academy of sciences Beijing 10094China

china’s lowland rural rivers are facing severe eutrophication problems due to excessive phosphorus(P)from anthropogenic ***,quantifying P dynamics in a lowland rural river is challenging due to its complex interaction with surrounding areas.A P dynamic model(River-P)was specifically designed for lowland rural rivers to address this *** modelwas coupled with the Environmental Fluid Dynamics Code(EFDC)and the Phosphorus Dynamic Model for lowland Polder systems(PDP)to characterize P dynamics under the impact of dredging in a lowland rural *** on a two-year(2020-2021)dataset from a representative lowland rural river in the Lake Taihu Basin,china,the coupled model was calibrated and achieved a model performance(R^(2)>0.59,RMSEresearch in the study river revealed that(1)the time scale for the effectiveness of sediment dredging for P control was~300 days,with an increase in P retention capacity by 74.8 kg/year and a decrease in TP concentrations of 23%after dredging.(2)Dredging significantly reduced P release from sediment by 98%,while increased P resuspension and settling capacities by 16%and 46%,respectively.(3)The sediment-water interface(SWI)plays a critical role in P transfer within the river,as resuspension accounts for 16%of TP imports,and settling accounts for 47%of TP *** the large P retention capacity of lowland rural rivers,drainage ditches and ponds with macrophytes are promising approaches to enhance P retention *** study provides valuable insights for local environmental departments,allowing a comprehensive understanding of P dynamics in lowland rural *** enable the evaluation of the efficacy of sediment dredging in P control and the implementation of corresponding P control measures.

关键词： Lowland rural river Phosphorus Sediment dredging Model ensemble Retention capacity