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Green Synthesis and Catalysis 2024年第2期5卷 102-107页

作者： Hui Zhang Bing Xu Liejin Zhou Zhan-Ming Zhang Junliang Zhang College of Marine ecology and Environment Shanghai Ocean University999 Hucheng Ring RoadShanghai 201306China Department of Chemistry Fudan University2005 Songhu RoadShanghai 200438China graduate School of Pharmaceutical Sciences Tohoku UniversitySendai 980-8578Japan Fudan Zhangjiang Institute Shanghai 201203China

Heterogeneous asymmetric catalysis is an important strategy for the industrial production of chiral ***,we reported a polymer-bound Xu-Phos-derived palladium catalyst that shows good performance in heterogeneous asymmetric reductive Heck reaction of allyl aryl *** heterogeneous catalyst was easily prepared by efficient immobilization of the sulfonamide phosphine ligand(Xu-Phos)in the cross-linked polystyrene via copolymerization,and exhibits similar catalytic activity and enantioselectivity to that of the homogeneous ***,the heterogeneous catalyst system is proved to be easily recovered and reused several times without losing catalytic activity obviously.

关键词： Heterogeneous catalysis Recoverability Palladium Hydroarylation Asymmetric catalysis

Potential distribution of Haloxylon ammodendron in Central Asia under climate change

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Journal of Arid Land 2024年第9期16卷 1255-1269页

作者： CHEN Zhuo SHAO Minghao HU Zihao GAO Xin LEI Jiaqiang Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China National Engineering Technology Research Center for Desert-Oasis Ecological Construction Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Emergency Management Beijing 101601China

Understanding the spatial distribution of plant species and their dynamic changes in arid areas is crucial for addressing the challenges posed by climate *** ammodendron shelterbelts are essential for the protection of plant resources and the control of desertification in Central *** far,the potential suitable habitats of *** in Central Asia are still uncertain in the future under global climate change *** study utilised the maximum entropy(MaxEnt)model to combine the current distribution data of *** with its growth-related data to analyze the potential distribution pattern of *** across Central *** results show that there are suitable habitats of *** in the Aralkum Desert,northern slopes of the Tianshan Mountains,and the upstream of the Tarim River and western edge of the Taklimakan Desert in the Tarim Basin under the current climate *** period from 2021 to 2040 is projected to undergo significant changes in the suitable habitat area of *** in Central Asia,with a projected 15.0% decrease in the unsuitable habitat *** areas farther from the ocean,such as the Caspian Sea and Aralkum Desert,will continue to experience a decrease in the suitable habitats of *** exhibiting frequent fluctuations in the habitat suitability levels are primarily found along the axis stretching from Astana to Kazakhskiy Melkosopochnik in *** regions can transition into suitable habitats under varying climate conditions,requiring the implementation of appropriate human intervention measures to prevent *** climate conditions are expected to cause an eastward shift in the geometric centre of the potential suitable habitats of ***,with the extent of this shift amplifying alongside more greenhouse gas *** study can provide theoretical support for the spatial configuration of *** shelterbelts and desertification co

关键词： Haloxylon ammodendron potential suitable habitats climate change desertification maximum entropy(MaxEnt)model Central Asia Aralkum Desert

Discrepant responses of soil organic carbon dynamics to nitrogen addition in different layers: a case study in an agroecosystem

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 314-325页

作者： Hualing HU Liang ZHAO Wenbing TAN Guoan WANG Beidou XI Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China

Empirical research indicates that heightened soil nitrogen availability can potentially diminish microbial decomposition of soil organic carbon(SOC).Nevertheless, the relationship between SOC turnover response to N addition and soil depth remains unclear. In this study, soils under varying N fertilizer application rates were sampled up to 100 cm deep to examine the contribution of both new and old carbon to SOC across different soil depths,using a coupled carbon and nitrogen isotopic approach. The SOC turnover time for the plot receiving low N addition(250 kg·ha^(-1)·yr^(-1) N) was about 20-40 years. Conversely, the plot receiving high N(450 kg·ha^(-1)·yr^(-1) N) had a longer SOC turnover time than the low N plot, reaching about 100 years in the upper 10-20 cm layer. The rise in SOC over the entire profile with low N addition primarily resulted from an increase in the upper soil(0-40 cm)whereas with high N addition, the increase was mainly from greater SOC in the deeper soil(40-100 cm). Throughout the entire soil layer, the proportion of new organic carbon derived from maize C_4 plant sources was higher in plots treated with a low N rate than those treated with a high N rate. This implies that, in contrast to low N addition agricultural practices, high N addition predominantly enhances the soil potential for fixing SOC by transporting organic matter from surface soils to deeper layers characterized by more stable properties. This research offers a unique insight into the dynamics of deep carbon under increased N deposition, thereby aiding in the formulation of policies for soil carbon management.

关键词： ^(13)C natural abundance nitrogen addition soil depth organic carbon turnover

Comparative Assessment of Impacts of Future Climate Change on Runoff in Upper Daqinghe Basin,China

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Chinese Geographical Science 2024年第3期34卷 564-578页

作者： INGABIRE Romaine CHANG Yuru LIU Xia CAO Bo UMUGWANEZA Adeline SHEN Yanjun Key Laboratory of Agricultural Water Resources Hebei-Key Laboratory of Water Saving AgricultureCenter for Agricultural Re-sources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022China Uni-versity of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Desert and Oasis ecology Xinjiang Insti-tute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China

Assessing runoff changes is of great importance especially its responses to the projected future climate change on local scale basins because such analyses are generally done on global and regional scales which may lead to generalized conclusions rather than specific *** change affected the runoff variation in the past in the upper Daqinghe Basin,however,the climate was mainly considered uncertain and still needs further studies,especially its future impacts on runoff for better water resources management and *** with a set of climate simulations,a daily conceptual hydrological model(MIKE11-NAM)was applied to assess the impact of climate change on runoff conditions in the Daomaguan,Fuping and Zijingguan basins in the upper Daqinghe *** hydrological data(2008–2017)were used to evaluate the applicability of the MIKE11-NAM *** bias correction,future projected climate change and its impacts on runoff(2025–2054)were analysed and compared to the baseline period(1985–2014)under three shared social economic pathways(SSP1-2.6,SSP2-4.5,and SSP5-8.5)scenarios from Coupled Model Intercomparison Project Phase 6(CMIP6)*** MIKE-11 NAM model was applicable in all three Basins,with both R^(2)and Nash-Sutcliffe Efficiency coefficients greater than 0.6 at daily scale for both calibration(2009–2011)and validation(2012–2017)periods,*** uncertainties remain,temperature and precipitation are projected to increase compared to the baseline where higher increases in precipitation and temperature are projected to occur under SSP2-4.5 and SSP5-8.5 scenarios,respectively in all the *** changes will range between 12%–19%whereas temperature change will be 2.0℃–2.5℃ under the SSP2-4.5 and SSP5-8.5 scenarios,*** addition,higher warming is projected to occur in colder months than in warmer ***,the runoff of these three basins is projected to respond to projected climate changes differe

关键词： runoff climate change MIKE11-NAM model Coupled Model Intercomparison Project Phase 6(CMIP6) upper Daqinghe Basin,China

Water-soluble brown carbon in atmospheric aerosols from the resource-dependent cities:Optical properties,chemical compositions and sources

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Journal of Environmental Sciences 2024年第4期138卷 74-87页

作者： Haoji Wang Yue Su Yangzheng Liu Fei Xie Xingjun Zhou Ruihong Yu Changwei Lü Jiang He School of ecology and Environment Inner Mongolia UniversityHohhot 010021China Institute of Environmental Geology Inner Mongolia UniversityHohhot 010021China Environmental Monitoring Center of Inner Mongolia Hohhot 010011China

As a vital type of light-absorbing aerosol,brown carbon(BrC)presents inherent associations with atmospheric photochemistry and climate ***,the understanding of the chemical and optical properties of BrC is limited,especially in some resource-dependent cities with long heating periods in northwest *** study showed that the annual average abundances of Water-soluble BrC(WS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and Wuhai and the concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency(MAE365)of WS-BrC presented significant seasonal patterns,with high values in the heating season and low values in the non-heating season;while showing opposite seasonal trends for the Absorption Angstr?m exponent(AAE_(300-400)).Comparatively,the levels of WS-BrC in developing regions(such as cities in Asia)were higher than those in developed regions(such as cities in Europe and Australia),indicating the significant differences in energy consumption in these *** combining fluorescence excitation-emission matrix(EEM)spectra with the parallel factor(PARAFAC)model,humic-like(C1 and C2)and proteinlike(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at Wuhai,*** results of source apportionment suggested that the potential source regions of WS-BrC varied in heating ***-heating seasons and that the properties of WS-BrC significantly depended on primary emissions(e.g.,combustion emissions)and secondary formation.

关键词： Water-soluble brown carbon Atmospheric aerosols Optical properties PARAFAC Source apportionment

Engineering high-performance dielectric chiral shells with enhanced chiral fields for sensitive chiral biosensor

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Rare Metals 2024年第3期43卷 1197-1206页

作者： Yi-Fan Wang Shan-Shan Huang Zhen-Dong Dai Shi-Lin Xian Xuan-Nan Wu Fu-Hua Gao Yi-Dong Hou College of Physics Sichuan UniversityChengdu610065China graduate School of Sichuan University Sichuan UniversityChengdu610065China

Chiral metamaterials have been a topic of significant research interest in recent years due to their potential for various applications in nanophotonic devices and chiral ***,the intrinsic Ohmic loss in surface plasmonic resonance has limited their practical use,resulting in large light dissipation and weak chiroptical ***,we report on the development of high-performance dielectric chiral shells(DCS)through a two-step Si deposition process on a self-assembled microsphere *** form DCS sample completely oyercomes the cancelation effect originated from the disorder property of the micro-sphere monolayer in macroscale,and at a wavelength of approximately 710 nm,the measured optimal chiral signal(g-factor)and transmittance can reach up to 0.7 and 0.3,*** strong chiroptical effect comes from the asymmetric circular displacement currents(i.e.,magnetic modes)enabled by the specific shell *** chiral shell geometry,electromagnetic properties,sensor sensitivity of chiral molecules and figure of merit are systematically *** DCSs demonstrate highly sensitive detection of chiral biomolecules owing to their easily accessible geometry and enhanced uniform chiral field.

关键词： Dielectric chiral shells(DCS) Si deposition Magnetic resonance Highly sensitive sensor Chiral field

Water quality, habitat, and fish assemblage relationships in middle-order agriculture and forest streams of the Mississippi Alluvial Plain

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Ecological Processes 2024年第1期13卷 217-236页

作者： Matthew L.Skoog Michael A.Eggleton Yushun Chen Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Minnesota Department of Natural Resources State Key Laboratory of Freshwater ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences

Background Agriculture has greatly influenced water quality, habitats, and fish assemblages in streams of the Mississippi Alluvial Plain(MAP) ecoregion. However, MAP streams have historically been understudied compared to streams in other agricultural regions of the USA. In this study, water quality, habitat, and fish assemblage composition were assessed seasonally(spring, summer, and fall) in eight representative MAP streams located across three U.S. states. The study design included four streams containing highly agricultural watersheds(herein termed “agriculture” streams) and four streams containing mostly forested watersheds(herein termed “forest” streams), which were intended to represent reference conditions for MAP *** In general, forest streams contained significantly better instream and riparian habitats than agriculture streams(P = 0.010–0.040) whereas agriculture streams contained significantly greater levels of primary nutrients(P < 0.001–0.010). Differences between agriculture and forest streams with respect to other physical and chemical variables were intermittent and season dependent. Fish assemblages in agriculture and forest streams were structured primarily along an environmental gradient reflecting instream habitat conditions, water nutrient concentrations, and benthic chlorophyll-a production. Structurally, fish assemblages in both stream types contained many regionally common species, though some species appeared to exhibit affinities for a particular stream type. Functionally, fish assemblages in agriculture streams contained more tolerant species, more omnivores, and fewer insectivores compared to forest stream assemblages, which were nearly all insectivores. Overall, one-third of the fish specimens collected in forest streams classified as intolerant *** Our results suggested that stream water quality, habitat, and fish assemblages differed between agriculture and forest streams in the MAP, with fish assemblages e

关键词： Agriculture Stream Land use Water quality Habitat Fish Multivariate statistics Mississippi Alluvial Plain

Effects of Ocean Acidification on Nitrogen Metabolism of Skeletonema costatum

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Journal of Ocean University of China 2024年第5期23卷 1359-1370页

作者： WANG Shuxing MI Tiezhu ZHEN Yu ZHU Jianbin Key Laboratory of Marine Environment and ecology Ministry of EducationCollege of Environmental Science and EngineeringOcean University of ChinaQingdao 266100China Laboratory for Marine ecology and Environmental Science Qingdao Marine Science and Technology CenterQingdao 266237China Frontiers Science Center for Deep Ocean Multispheres and Earth System Ocean University of ChinaQingdao 266100China

Ocean acidification(OA),caused by the rising concentration of atmospheric CO_(2),leads to changes in the marine carbonate ***,in turn,affects the physiological processes of *** response to increased pCO_(2) levels,marine microalgae modulate their physiological responses to meet their energy and metabolic *** metabolism is a critical metabolic pathway,directly affecting the growth and reproductive capacity of marine *** the molecular mechanisms that regulate nitrogen metabolism in microalgae under OA conditions is therefore *** study aimed to investi-gate how OA affects the expression profiles of key genes in the nitrogen metabolic pathway of the marine diatom Skeletonema *** findings indicate that OA upregulates key genes involved in the nitrogen metabolic pathway,specifically those related to nitrate assimilation and glutamate ***,pCO_(2) has been identified as the predominant factor affecting the expression of these genes,with a more significant impact than pH variations in *** research not only advances our understanding of the adaptive mechanisms of *** in response to OA but also provides essential data for predicting the ecological consequences of OA on marine diatoms.

关键词： Skeletonema costatum ocean acidification nitrogen metabolism gene expression transcriptome

Pollen analysis reveals the effects of uncovered interactions,pollen-carrying structures,and pollinator sex on the structure of wild bee-plant networks

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Insect Science 2024年第3期31卷 971-988页

作者： Clément Tourbez Carmelo Gómez-Martínez MiguelÁngel Gonzalez-Estévez Amparo Lazaro Mediterranean Institute for Advanced Studies(UIB-CSIC) Global Change Research GroupEsporlesBalearic IslandsSpain Department of Biology Ecology AreaUniversity of the Balearic/slandsPalmaSpain

Pollination networks are increasingly used to model the complexity of interactions between pollinators and flowering plants in *** methods exist to sample these interactions,with direct observations of plant-pollinator contacts in the field being by far the most *** the identification of pollen carried by pollinators allows uncovering interactions and increasing sample sizes,the methods used to build pollen-transport networks are variable and their effect on network structure remains *** understand how interaction sampling influences the structure of networks,we analyzed the pollen found on wild bees from eight communities across Mallorca Island and investigated the differences in pollen loads between bee body parts(scopa ***)and *** then assessed how these differences,as well as the uncovered interactions not detected in the field,influenced the structure of wild bee-plant *** identified a higher quantity and diversity of pollen in the scopa than in the rest of the female body,but these differences did not lead to differences in structure between plant-pollination(excluding scopa pollen)and bee-feeding interaction(including scopa pollen)***,networks built with pollen data were richer in plant species and interactions and showed lower modularity and specialization(H2'),and higher nestedness than visitation networks based on field *** interactions with plants were stronger compared to those of males,although not ***,females were more generalist(low d')and tended to be more central in interaction networks,indicating their more key role structuring pollination networks in comparison to *** study highlights the importance of palynological data to increase the resolution of networks,as well as to understand important ecological questions such as the differences between plant-pollination and bee-feeding interaction networks,and the role of sexes in pollination.

关键词： palynology pollen-transport networks pollination role of bee sexes sampling methodology visitation networks

High leaf area index expands the contrasting effect of climate warming on Western Siberia taiga forests activity before and after 2000

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Journal of Geographical Sciences 2024年第1期34卷 131-145页

作者： SUN Han WANG Xiangping State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing 100083China School of ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China

The taiga vegetation in Western Siberia has been seriously threatened by climate warming in recent ***,how vegetation in different growing states and climate conditions responds to climate changes differently is still *** we explore the vegetation activity trends in Western Siberia taiga forests using the annual rate of change in leaf area index(LAI)during 1982–2018 so as to answer two questions:(1)how did climate warming affect taiga vegetation activity in the recent last decades?(2)Did the growing state of taiga forest affect its response to climate warming?Our results revealed that climate warming promoted taiga vegetation activity in Western Siberia before ***,continuous warming caused excessive evapotranspiration and led to decreased vegetation activity after ***,the intensity of vegetation growth response to warming was positively related to canopy height and LAI,indicating that both the positive and negative effects of warming were more significant in taiga forests in better growing *** these forests generally have higher productivity and play more important roles in ecosystem functioning(e.g.,carbon sink and biodiversity conservation),our results highlight their vulnerability to future climate change that need more research attention.

关键词： climate warming taiga forest leaf area index(LAI) vegetation activity Western Siberia