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Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations: a global data synthesis

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JOURNAL OF forestry RESEARCH 2024年第1期35卷 1-11页

作者： Nie, Xiuqing Wang, Hui Wang, Jian Liu, Shirong chinese acad forestry Ecol & Nat Conservat Inst Key Lab Forest Ecol & Environm Natl Forestry & Gra 2 Dongxiaofu Beijing 100091 Peoples R China

Different chemical compositions of soil organic carbon (SOC) affect its persistence and whether it significantly differs between natural forests and plantations remains unclear. By synthesizing 234 observations of SOC chemical compositions, we evaluated global patterns of concentration, individual chemical composition (alkyl C, O-alkyl C, aromatic C, and carbonyl C), and their distribution evenness. Our results indicate a notably higher SOC, a markedly larger proportion of recalcitrant alkyl C, and lower easily decomposed carbonyl C proportion in natural forests. However, SOC chemical compositions were appreciably more evenly distributed in plantations. Based on the assumed conceptual index of SOC chemical composition evenness, we deduced that, compared to natural forests, plantations may have higher possible resistance to SOC decomposition under disturbances. In tropical regions, SOC levels, recalcitrant SOC chemical composition, and their distributed evenness were significantly higher in natural forests, indicating that SOC has higher chemical stability and possible resistance to decomposition. Climate factors had minor effects on alkyl C in forests globally, while they notably affected SOC chemical composition in tropical forests. This could contribute to the differences in chemical compositions and their distributed evenness between plantations and natural stands.

关键词： Global data synthesis Natural forest Plantations Soil organic carbon Soil organic carbon chemical composition STATE C-13 NMR SPATIAL-DISTRIBUTION MICROBIAL COMMUNITY MATTER FRACTIONS QUALITY SEQUESTRATION STABILIZATION DECOMPOSITION DIVERSITY

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Tree allometry responses to competition and complementarity in mixed-species plantations of Betula alnoides

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Forest Ecosystems 2024年第4期11卷 469-479页

作者： Boyao Chen Kaili Liu Chunsheng Wang Junjie Guo Junkun Lu Lin Chen Zhigang Zhao Jie Zeng Research Institute of Tropical forestry Chinese Academy of ForestryGuangzhou510520China Central South University of forestry&Technology Changsha410004China Experimental Center of Tropical forestry Chinese Academy of ForestryPingxiang532600China Nanjing forestry University Nanjing210037China

Tree allometry plays a crucial role in tree survival,stability,and timber quantity and quality of mixed-species ***,the responses of tree allometry to resource utilisation within the framework of interspecific competition and complementarity remain poorly *** into consideration strong-and weakspace competition(SC and WC),as well as N_(2)-fixing and non-N_(2)-fixing tree species(FN and nFN),a mixedspecies planting trial was conducted for Betula alnoides,a pioneer tree species,which was separately mixed with Acacia melanoxylon(SC+FN),Erythrophleum fordii(WC+FN),Eucalyptus cloeziana(SC+nFN)and Pinus kesiya ***(WC+nFN)in southern *** years after planting,tree growth,total nitrogen(N)and carbon(C)contents,and the natural abundances of^(15)N and^(13)C in the leaves were measured for each species,and the mycorrhizal colonisation rates of *** were investigated under each *** variations and their relationships with space competition and nutrient-related factors were *** results showed a consistent effect of space competition on the height-diameter relationship of *** in mixtures with FN or *** tree height growth of *** was significantly promoted under high space competition,and growth in diameter at breast height(DBH),tree height and crown size were all expedited in mixtures with *** symbiotic relationship between ectomycorrhizal fungi and *** was significantly influenced by both space competition and N_(2) fixation by the accompanying tree species,whereas such significant effects were absent for arbuscular mycorrhizal ***,high space competition significantly decreased the water use efficiency(WUE)of ***,and its N use efficiency(NUE)was much lower in the FN *** equation modeling further demonstrated that the stem allometry of *** was affected by its NUE and WUE via changes in its height growth,and crown allometry was influ

关键词： Allometric relationship Resources competition and complementarity Mixed-species forest Tree-fungal symbiotic relationship N_2-fixing tree species Resource utilisation strategies

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A real-time calibration method based on time-to-digital converter for accelerator timing system

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第9期35卷 1-14页

作者： Duan, Qi-Hao Ge, Liang Jia, Yan-Hao Zhu, Jie-Yu Zhang, Wei chinese acad Sci Inst modern Phys Lanzhou 730000 Peoples R China Univ chinese acad Sci Beijing 100049 Peoples R China

The high-intensity heavy-ion accelerator facility (HIAF) is a scientific research facility complex composed of multiple cascade accelerators of different types, which pose a scheduling problem for devices distributed over a certain range of 2 km, involving over a hundred devices. The white rabbit, a technology-enhancing Gigabit Ethernet, has shown the capability of scheduling distributed timing devices but still faces the challenge of obtaining real-time synchronization calibration parameters with high precision. This study presents a calibration system based on a time-to-digital converter implemented on an ARM-based System-on-Chip (SoC). The system consists of four multi-sample delay lines, a bubble-proof encoder, an edge controller for managing data from different channels, and a highly effective calibration module that benefits from the SoC architecture. The performance was evaluated with an average RMS precision of 5.51 ps by measuring the time intervals from 0 to 24,000 ps with 120,000 data for every test. The design presented in this study refines the calibration precision of the HIAF timing system. This eliminates the errors caused by manual calibration without efficiency loss and provides data support for fault diagnosis. It can also be easily tailored or ported to other devices for specific applications and provides more space for developing timing systems for particle accelerators, such as white rabbits on HIAF.

关键词： HIAF White rabbit Calibration system Time-to-digital converter (TDC) FPGA

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Discrimination of pharmacodynamic components and volatile compounds of Poria cocos cultivated with five different materials based on GC-IMS analysis

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Food Quality and Safety 2024年第1期8卷 135-144页

作者： Yinan Wang Fei Zhou Hui Wang Jinping Zhang Hongxia Xu Research Institute of Subtropical forestry Chinese Academy of ForestryHangzhouChina Chun‘an County Thousand-island Lake Forest Farm HangzhouChina

Objectives:The chemical constituents of Poria cocos grown with different substrates vary significantly;thus,identifying and comparing their biomarkers are *** and Methods:Herein,the chemical constituents of Poria cocos obtained with five different substrates were assessed using gas chromatography–ion mobility spectrometry(GC-IMS),high-performance liquid chromatography and multivariate statistical ***:The content of moisture,ash,alcohol-soluble matter,and heavy metals,except for those of the miscellaneous wood Poria cocos,conform to the specifications defined in the chinese Pharmacopoeia(Edition 2020),and the polysaccharide contents are all greater than 57%.Conclusions:Based on GC-IMS and the established fingerprints,87 compounds were detected,70 of which were identified in each *** statistical analysis revealed seven compounds(two esters,three alcohols,and two aldehydes),which could be considered as potential marker compounds for discrimination.

关键词： Poria cocos cultivation material pharmacodynamic component gas chromatography-ion mobility spectrometry(GC-IMS) volatile compound.

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More tree growth reduction due to consecutive drought and its legacy effect for a semiarid larch plantation in Northwest China

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Journal of forestry Research 2024年第2期35卷 188-196页

作者： Yanfang Wan Pengtao Yu Yanhui Wang Jiamei Li Yushi Bai Yipeng Yu Bingbing Liu Xiaocha Wei Key Laboratory of Forest Ecology and Environment of National forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091People’s Republic of China

Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more ***,it is poorly understood how tree growth is affected by different drought *** 2006–2009,the larch plantations in the semiarid areas of Northwest China were negatively affected by four consecutive dry years,which was a very rare phenomenon that may occur frequently under future climate *** this study,we analyzed the effect of these consecutive dry years on tree growth based on the data of the tree rings in the dominant layer of the forest canopy on a larch *** found that the tree-ring width index(RWI)in dry years was lower than that in normal years,and it experienced a rapidly decreasing trend from 2006 to 2009(slope=-0.139 year^(-1),r=-0.94)due to water supply deficits in those dry *** induced legacy effects of tree growth reduction,and consecutive dry years corresponded with greater growth reductions and legacy *** reductions and legacy effects were significantly stronger in the third and fourth consecutive dry years than that of single dry year(p<0.05),which might have been due to the cumulative stress caused by consecutive dry *** results showed that larch trees experienced greater tree growth reduction due to consecutive dry years and their legacy effect,and the trees had lower recovery rates after consecutive dry *** results highlight that consecutive dry years pose a new threat to plantations under climate warming,and thus,the effect of climate extremes on tree growth should be considered in growth models in semiarid areas.

关键词： Tree rings Drought effects Legacy effects Growth-climate relationships Larix principis-rupprechtii

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Long-term changes in radial growth of seven tree species in the mixed broadleaf-Korean pine forest in Northeast China: Are deciduous trees favored by climate change?

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JOURNAL OF forestry RESEARCH 2024年第1期35卷 1-15页

作者： Gong, Xiufang Yuan, Danyang Zhu, Liangjun Li, Zongshan Wang, Xiaochun Cent South Univ forestry & Technol Coll Life Sci & Technol Natl Engn Lab Appl Technol Forestry & Ecol South C Changsha 410004 Peoples R China Northeast forestry Univ Ctr Ecol Res Sch Forestry Harbin 150040 Peoples R China Northeast forestry Univ Sch Forestry Key Lab Sustainable Forest Ecosyst Management Minist Educ Harbin 150040 Peoples R China chinese acad Sci Res Ctr Ecoenvironm Sci State Key Lab Urban & Reg Ecol Beijing 100085 Peoples R China

The role of the temperate mixed broadleaf-Korean pine forest (BKF) in global biogeochemical cycles will depend on how the tree species community responds to climate; however, species-specific responses and vulnerabilities of common trees in BKF to extreme climates are poorly understood. Here we used dendrochronological methods to assess radial growth of seven main tree species (Pinus koraiensis, Picea jezoensis, Abies nephrolepis, Fraxinus mandshurica, Phellodendron amurense, Quercus mongolica, and Ulmus davidiana) in an old-growth BKF in response to climate changes in the Xiaoxing'an Mountains and to improve predictions of changes in the tree species composition. Temperature in most months and winter precipitation significantly negatively affected growth of P. jezoensis and A. nephrolepis, but positively impacted growth of P. koraiensis and the broadleaf species, especially F. mandshurica and U. davidiana. Precipitation and relative humidity in June significantly positively impacted the growth of most tree species. The positive effect of the temperature during the previous non-growing season (PNG) on growth of F. mandshurica and Q. mongolica strengthened significantly with rapid warming around 1981, while the impact of PNG temperature on the growth of P. jezoensis and A. nephrolepis changed from significantly negative to weakly negative or positive at this time. The negative response of radial growth of P. jezoensis and A. nephrolepis to precipitation during the growing season gradually weakened, and the negative response to PNG precipitation was enhanced. Among the studied species, P. koraiensis was the most resistant to drought, and U. davidiana recovered the best after extreme drought. Ulmus davidiana, P. jezoensis and A. nephrolepis were more resistant to extreme cold than the other species. Climate warming generally exacerbated the opposite growth patterns of conifer (decline) and broadleaf (increase) species. Deciduous broadleaf tree species in the old-growth

关键词： Tree rings Extreme climate Resistance and recovery Broad-leaved and Korean pine mixed forest DROUGHT TEMPERATURE RESPONSES KORAIENSIS RESILIENCE DYNAMICS IMPACT XYLEM

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Less pressure contributes to gravity-driven membrane ultrafiltration with greater performance:Enhanced driving efficiency and reduced disinfection by-products formation potential

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Journal of Environmental Sciences 2024年第3期137卷 407-419页

作者： Xiaoting Wu Yufei Li Zhaoyang Su Long Tian Muhammad Saboor Siddique Wenzheng Yu Colleges of forestry Northeast Forestry UniversityHarbin 150040China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Gravity-driven membrane(GDM)systems have been well developed previously;however,impacts of driving(i.e.,transmembrane)pressure on their performance received little attention,which may infuence GDM *** this study,we evaluated 4 GDM systems via altering the transmembrane pressure from 50 mbar to 150 mbar with 2 groups,treating surface water in Beijing,*** showed that less driving pressure was more ***,compared to groups(150 mbar),groups under a pressure of 50 mbar were found to have greater normalized permeability and lower total *** the whole operation period,the quality of effuents was gradually *** example,the removal efficiency of UV254was significantly improved;particularly,under low driving pressure,the removal efficiency of UV254in PES GDM system increased by 11.91%,as compared to the corresponding system under high driving *** observation was consistent with the reduction on disinfection by-products(DBPs)formation potential;groups under 50 mbar achieved better DBPs potential control,indicating the advantages of lower driving *** were analyzed and responsible for these differences,and distinct distributions of bacteria communities of two GDM systems under 50 and 150 mbar may be responsible for various humic-like substances removal ***,GDM systems under less pressure should be considered and expected to provide suggestions on the design of GDM systems in real applications.

关键词： Ultrafiltration Gravity driven operation Membrane fouling Biofilms Disinfection by-products

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Molecular evolution of Toll-like receptors in rodents

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Integrative Zoology 2024年第3期19卷 371-386页

作者： Qianqian SU Yi CHEN Hongxuan HE College of forestry Central South University of Forestry and TechnologyChangshaChina National Research Center for Wildlife-Borne Diseases Institute of ZoologyChinese Academy of SciencesBeijingChina

Toll-like receptors(TLRs),the key sensor molecules in vertebrates,trigger the innate immunity and prime the adaptive immune *** TLR family of rodents,the largest order of mammals,typically contains 13 TLR ***,a clear picture of the evolution of the rodent TLR family has not yet emerged and the TLR evolutionary patterns are unclear in rodent ***,we analyzed the natural variation and the evolutionary processes acting on the TLR family in rodents at both the interspecific and population *** results showed that rodent TLRs were dominated by purifying selection,but a series of positively selected sites(PSSs)primarily located in the ligand-binding domain was also *** numbers of PSSs differed among TLRs,and nonviralsensing TLRs had more PSSs than those in viral-sensing ***-conversion events were found between TLR1 and TLR6 in most rodent *** genetic analyses showed that TLR2,TLR8,and TLR12 were under positive selection in Rattus norvegicus and ***,whereas positive selection also acted on TLR5 and TLR9 in the former species,as well as TLR1 and TLR7 in the latter ***,we found that the proportion of polymorphisms with potentially functional change was much lower in viral-sensing TLRs than in nonviral-sensing TLRs in both of these rat *** findings revealed the first thorough insight into the evolution of the rodent TLR genetic variability and provided important novel insights into the evolutionary history of TLRs over long and short timescales.

关键词： adaptive evolution gene conversion positive selection rodents Toll-like receptors

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Spatio-temporal variation of water salinity in mangroves revealed by continuous monitoring and its relationship to floristic diversity

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Plant Diversity 2024年第1期46卷 134-143页

作者： Wei Wang Kun Xin Yujun Chen Yuechao Chen Zhongmao Jiang Nong Sheng Baowen Liao Yanmei Xiong Research Institute of Tropical forestry Chinese Academy of ForestryGuangzhou 510520PR China Guangdong Zhanjiang Mangrove National Nature Reserve Administration Zhanjiang 524088PR China

Salinity is among the most critical factors limiting the growth and species distribution of coastal *** salinity in estuarine ecosystems varies temporally and spatially,but the variation patterns across different time scales and salinity fluctuation have rarely been *** effects of salinity on floristic diversity in mangroves are not fully understood due to the temporal and spatial heterogeneity of *** this study,we monitored water salinity at an interval of 10-min over one year in three mangrove catchment areas representing the outer part,middle part,and inner part respectively of Dongzhai Bay,Hainan,*** number of mangrove community types and dominant mangrove species of the three catchment areas were also *** found that the diurnal variation and dry-season intra-month variation in water salinity were driven by tidal *** seasonal variation in water salinity was mainly driven by rainfall with higher salinity occurring in the dry season and lower salinity occurring in the wet ***,water salinity was highest at the outer part,intermediate at the middle part,and lowest at the inner part of the *** intra-month and annual fluctuations of water salinity were highest at the middle part and lowest at the outer part of the *** number of mangrove community types and dominant species were lowest at the outer part,intermediate at the middle part,and highest at the inner part of the *** results suggest that the temporal variation of water salinity in mangroves is driven by different factors at different time scales and therefore it is necessary to measure water salinity at different time scales to get a complete picture of the saline environment that mangroves ***,lower salinity levels benefit mangrove species richness within a bay landscape,however,further research is needed to distinguish the effects of salinity fluctuation and salinity level in affecting mangrove species richness.

关键词： Coastal wetlands Mangroves Salinity fluctuation Species diversity Species richness

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Optimization of fertilizer performances in long-term garlic cropping soils

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Pedosphere 2024年第3期34卷 577-589页

作者： Tianqi WEI Hongmei ZHOU Huayang HONG Yanyun REN Qin LIU Yanhua SU Institute of Soil Science Chinese Academy of SciencesNanjing 210008(China) University of chinese academy of Sciences Beijing 100049(China) University of chinese academy of Sciences NanjingNanjing 211135(China) Jining academy of Agricultural Sciences Jining 272100(China) College of forestry Nanjing Forestry UniversityNanjing 210037(China)

Continuous cropping is a common pattern of modern agriculture that takes regional advantages for crop yield *** the progress of mono-cropping continuously supported by intensive fertilizer inputs,such a cropping pattern often undergoes serious problems with low fertilizer use efficiencies and unsustainable crop *** this study,we dealt with a>25-year continuous garlic cropping system as an example for a problem-solving *** garlic cropping soils underwent problems characterized by loss of soil organic matter,dramatic retention of NH_(4)^(+)-N,and excess accumulation of phosphate and potash *** hydroponic simulations,we revealed that the presence of NH_(4)^(+)-N inhibited the root uptake of NO_(3)^(-)-N and K by 68% and 88%,*** the traditionally emphasized importance of K,we observed the negative effect of high K on the growth of garlic *** field experiments demonstrated that P and K applications can be reduced by 60% and 50%,respectively,without loss of *** thus developed a high-performance fertilization strategy by integrating a recomposed NPK fertilizer formulation to reduce unnecessary P and K inputs,a supplementary application of long-lasting C of woody peat to compensate for the soil C loss,and a foliar K approach to strengthen the stomatal function improvement with *** strategy allowed a 15% increase of garlic yield and a seasonal soil C profit of ca.1.8 Mg ha^(-1)even at ca.30% lower fertilizer *** study would be helpful in managing garlic fertilization and developing compound fertilizers,with broader significance for other long-term cropping soils.

关键词： fertilization strategy fertilizer input field validation hydroponic simulation optimized fertilization soil nutrient balance yield profit

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