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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 vulnerable.However,it is poorly understood how tree growth is affected by different drought events.In 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 warming.In 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 plantation.We 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 years.Drought induced legacy effects of tree growth reduction,and consecutive dry years corresponded with greater growth reductions and legacy effects.Growth 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 years.Our 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 years.Our 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

Accurate Shortwave Radiation Simulation with a Two-Layer Aerosol Model in Xinjiang Region

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Journal of Meteorological Research 2024年第1期38卷 69-87页

作者： Guan HUANG Yonghang CHEN Qiong LIU pengtao wang Qianshan HE Qing HE Shuai LI Weiling SHAO Ting FAN School of Tourism&Research Institute of Human Geography Xi’an International Studies UniversityXi’an 710128 Center for Silk Road and Eurasian Civilization Studies Xi’an International Studies UniversityXi’an 710128 College of Environmental Science and Engineering Donghua UniversityShanghai 201620 Shanghai Meteorological Service Shanghai 200030 Shanghai Key Laboratory of Meteorology and Health Shanghai 200030 Taklimakan Desert Meteorology Field Experiment Station of China Meteorological Administration Institute of Desert MeteorologyUrumqi 830002 Xinjiang Climate Centre Xinjiang Meteorological ServiceUrumqi 830002

To harness the rich solar energy resources in Xinjiang Region of Northwest China,this study tries to address the issue of lack of downward surface shortwave radiation(DSSR)observations and the need to improve the accuracy of satellite retrieval and numerical simulation of DSSR under varied sky and meteorological conditions.(1)A two-layer aerosol model specific to Xinjiang was developed to capture the vertical distributions of aerosols based on multiple data sources including lidar,GPS sounding,ground meteorological observations,and profiles from the ECMWF reanalysis version 5(ERA5)data.The results show that the ERA5/PBLH(planetary boundary layer height)and ERA5/ALH(aerosol layer height)could be used to establish the two-layer aerosol model and characterize the vertical distribution of aerosols in Xinjiang Region.(2)Using the Santa Barbara Discrete Atmospheric Radiative Transfer(SBDART)model,a localized inverse model of clear-sky DSSR was established.After parameter adjustment and using the optimal combination of input parameters for DSSR simulation together with the two-layer aerosol model,the model-simulated DSSR(DSSRSBD)under clear-sky conditions improved significantly compared to the initial results,with all fitting indices greatly improved.(3)In addition,the study demonstrated that the impact of the two-layer aerosol model on DSSR was more pronounced under dust conditions than clear-sky conditions.(4)Using the localized clear-sky DSSR inversion model and its required parameters,simulations were also conducted to capture the spatiotemporal distribution of DSSR under clear-sky conditions in Xinjiang from 2017 to 2019.The annual average DSSR_(SBD)under clear-sky conditions in Xinjiang during 2017–2019 was 606.78 W m^(-2),while DSSR from CERES(DSSR_(CER))under the same conditions was generally higher(703.95 W m^(-2)).(5)It is found that satellite remote sensing products experienced data loss in high-altitude snow areas,where numerical simulation technology could serve as a valuable complement.

关键词： downward surface shortwave radiation(DSSR) aerosol vertical distribution Clouds and the Earth’s Radiant Energy System(CERES) Santa Barbara Discrete Atmospheric Radiative Transfer(SBDART) Xinjiang

Increased long-distance and homo-trans interactions related to H3K27me3 in Arabidopsis hybrids

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Journal of Integrative Plant Biology 2024年第2期66卷 208-227页

作者： Zhaoxu Gao Yanning Su Le Chang Guanzhong Jiao Yang Ou Mei Yang Chao Xu pengtao Liu Zejia wang Zewen Qi Wenwen Liu Linhua Sun Guangming He Xing wang Deng Hang He School of Advanced Agriculture Sciences and School of Life Sciences State Key Laboratory of Protein and Plant Gene ResearchPeking UniversityBeijing 100871China College of Grassland Science Beijing Forestry UniversityBeijing 100083China Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agricultural Sciences in WeifangWeifang 261325China

In plants,the genome structure of hybrids changes compared with their parents,but the effects of these changes in hybrids remain elusive.Comparing reciprocal crosses between Col×C24 and C24×Col in Arabidopsis using high-throughput chromosome conformation capture assay(Hi-C)analysis,we found that hybrid three-dimensional(3D)chromatin organization had more long-distance interactions relative to parents,and this was mainly located in promoter regions and enriched in genes with heterosis-related pathways.The interactions between euchromatin and heterochromatin were increased,and the compartment strength decreased in hybrids.In compartment domain(CD)boundaries,the distal interactions were more in hybrids than their parents.In the hybrids of CURLY LEAF(clf)mutants clfCol×clfC24and clfC24×clfCol,the heterosis phenotype was damaged,and the long-distance interactions in hybrids were fewer than in their parents with lower H3K27me3.ChIP-seq data revealed higher levels of H3K27me3 in the region adjacent to the CD boundary and the same interactional homo-trans sites in the wild-type(WT)hybrids,which may have led to more long-distance interactions.In addition,the differentially expressed genes(DEGs)located in the boundaries of CDs and loop regions changed obviously in WT,and the functional enrichment for DEGs was different between WT and clf in the longdistance interactions and loop regions.Our findings may therefore propose a new epigenetic explanation of heterosis in the Arabidopsis hybrids and provide new insights into crop breeding and yield increase.

关键词： 3D chromatin organization H3K27me3 homo-trans hybrids long-distanceinteractions

Seasonal Responses of Net Primary Productivity of Vegetation to Phenological Dynamics in the Loess Plateau, China

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Chinese Geographical Science 2022年第2期32卷 340-357页

作者： HAN Hongzhu BAI Jianjun MA Gao YAN Jianwu wang Xiaohui TA Zhijie wang pengtao School of Tourism&Research Institute of Human Geography Xi'an International Studies UniversityXi'an 710128China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China China Academy of Space Technology-Xi'an Xi'an 710000China School of Humanities and Social Sciences Xi'an University of Posts and TelecommunicationsXi'an 710121China

With global warming, the great changes in the patterns of plant growth have occurred. The conditions in early spring and late autumn have changed the process of vegetation photosynthesis, which are expected to have a significant impact on net primary productivity(NPP) and affect the global carbon cycle. Currently, the seasonal response characteristics of NPP to phenological changes in dryland ecosystems are still not well defined. This article calibrated and analyzed the normalized difference vegetation index(NDVI)time series of Advanced Very-High-Resolution Radiometer(AVHRR) data from 1982 to 2015 in the Loess Plateau, China. The spatial and temporal distributions of vegetation phenology and NPP in the Loess Plateau under semihumid and semiarid conditions were investigated. The seasonal variation in the NPP response to vegetation phenology under the climate change was also analyzed. The results showed that, different from the northern forest, there was distinct spatial heterogeneity in the effect of climate change on the dynamic change in vegetation growth in the Loess Plateau: 1) an advance of the start of the growing season(SOS) and a delay of the end of the growing season(EOS) significantly increased the NPP in spring and autumn, respectively, in the humid southeast;2) in the arid northwest, the NPP did not significantly increase in spring and autumn but significantly decreased in summer.

关键词： climate change normalized difference vegetation index phenology net primary productivity Loess Plateau,China

全民阅读背景下数字阅读供给的自治理机制设计

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出版发行研究 2024年第4期 18-24,90页

作者：王鹏涛南京大学信息管理学院

在全民阅读发展过程中,拓展阅读对象的种类与范围固然重要,但如何保障这些出版物尤其是数字阅读供给的质量与可靠性,已成为亟须解决的问题。文章构建了数字阅读供给质量的自治理机制,以适应数字时代的新趋势,解决当前阅读推广中面临的... 详细信息

在全民阅读发展过程中,拓展阅读对象的种类与范围固然重要,但如何保障这些出版物尤其是数字阅读供给的质量与可靠性,已成为亟须解决的问题。文章构建了数字阅读供给质量的自治理机制,以适应数字时代的新趋势,解决当前阅读推广中面临的新问题。该机制强调通过制定明确的规则和标准、建立多方协同的评估体系、确保全程信息公开透明、鼓励用户反馈与参与,以及公布违约责任和惩罚措施等方式,全面提升阅读推广的效果,确保公民能够获取优质、安全的数字阅读资源,推动全民阅读工作深入发展,促进出版业以及公共文化事业繁荣兴盛。

关键词：全民阅读数字出版物自治理机制

人机协同审核:出版审核工作智能化转型的必经之路

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出版科学 2024年第2期32卷 105-111页

作者：宋明珍王鹏涛南京大学信息管理学院/出版融合发展战略研究所南京210023

阐述人机协同模式在出版审核工作中的价值,提出在把握以编辑为主体、共建共享、需求导向以及共识先行的原则基础上构建人机协同出版审核系统,从而改变传统出版审核工作流程和模式,提升审核工作的效率和效果。从政府部门、出版机构、编... 详细信息

阐述人机协同模式在出版审核工作中的价值,提出在把握以编辑为主体、共建共享、需求导向以及共识先行的原则基础上构建人机协同出版审核系统,从而改变传统出版审核工作流程和模式,提升审核工作的效率和效果。从政府部门、出版机构、编辑个人三个层面为新型出版审核模式的落实给出具体的行动建议。

关键词：出版审核人机协同智能出版人工智能数字出版

Probability Analysis of the Wave-Slamming Pressure Values of the Horizontal Deck with Elastic Support

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Journal of Ocean University of China 2018年第3期17卷 507-515页

作者： ZUO Weiguang LIU Ming FAN Tianhui wang pengtao North China University of Water Resources and Electric Power Zhengzhou 450045 China CCCC First Harbor Engineering Company Ltd. Tianjin 300461 China South China University of Technology Guangzhou 510640 China

This paper presents the probability distribution of the slamming pressure from an experimental study of regular wave slamming on an elastically supported horizontal deck. The time series of the slamming pressure during the wave impact were first obtained through statistical analyses on experimental data. The exceeding probability distribution of the maximum slamming pressure peak and distribution parameters were analyzed, and the results show that the exceeding probability distribution of the maximum slamming pressure peak accords with the three-parameter Weibull distribution. Furthermore, the range and relationships of the distribution parameters were studied. The sum of the location parameter D and the scale parameter L was approximately equal to 1.0, and the exceeding probability was more than 36.79% when the random peak was equal to the sample average during the wave impact. The variation of the distribution parameters and slamming pressure under different model conditions were comprehensively presented, and the parameter values of the Weibull distribution of wave-slamming pressure peaks were different due to different test models. The parameter values were found to decrease due to the increased stiffness of the elastic support. The damage criterion of the structure model caused by the wave impact was initially discussed, and the structure model was destroyed when the average slamming time was greater than a certain value during the duration of the wave impact. The conclusions of the experimental study were then described.

关键词：撞击压力概率分析波浪价值弹性水准甲板 Weibull

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实体书店红色文化空间构建与延伸路径研究

出版发行研究 2024年第1期 18-23,11页

作者：朱赫男王鹏涛南京大学信息管理学院

建党百年来,实体书店始终是红色文化传播的重要空间。作为出版物的陈列售卖空间、读者的交流互动空间和思想文化的传播空间,实体书店具有思想性和文化性的场所特性。新时代实体书店做好宣传思想文化工作,需要借助叙事使红色文化深入人... 详细信息

建党百年来,实体书店始终是红色文化传播的重要空间。作为出版物的陈列售卖空间、读者的交流互动空间和思想文化的传播空间,实体书店具有思想性和文化性的场所特性。新时代实体书店做好宣传思想文化工作,需要借助叙事使红色文化深入人心。实体书店作为文化空间具有物质性和精神性融合、在地性与相关性交织、延展性与再生产性联结的特点。文章基于书店文化空间的特点,从空间叙事角度,提出在文本层、时空体层和地志层将场所精神和红色文化融入实体书店环境,构建红色文化空间的路径,并进一步探索实体书店红色文化空间从物理空间向虚拟空间、从公共空间向私人空间的延伸路径,促进读者在多重空间中形成对红色文化的认同。

关键词：实体书店空间叙事红色文化场所精神记忆共同体

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采煤机截割部低照度图像的边缘检测技术

煤田地质与勘探 2024年第4期52卷 172-178页

作者：贾澎涛靳路伟王斌郭风景李娜西安科技大学计算机科学与技术学院陕西西安710054 陕西建新煤化有限责任公司陕西黄陵727300 陕西陕煤蒲白矿业有限公司陕西渭南715517

针对井下低照度环境下采煤机截割部边缘检测任务中存在的边缘缺失、细节模糊等问题,提出一种基于分数阶微分的边缘检测Lif算法。首先采用更大的检测模板尺寸,根据Grünwald-Let-nikov分数阶定义构造最初的分数阶掩膜算子;然后根据Pasca... 详细信息

针对井下低照度环境下采煤机截割部边缘检测任务中存在的边缘缺失、细节模糊等问题,提出一种基于分数阶微分的边缘检测Lif算法。首先采用更大的检测模板尺寸,根据Grünwald-Let-nikov分数阶定义构造最初的分数阶掩膜算子;然后根据Pascal三角形理论确定掩膜算子上各位置的权重系数,并将掩膜算子扩展到4个不同方向;最后将得到的掩膜算子与图像进行卷积,利用图像的局部特征信息对每个方向的微分结果进行后处理。结果表明:(1)在进行多个不同场景的井下低照度图像上的实验时,Lif算法可以更全面地获取图像中不同方向上的边缘信息,在处理低照度图像时具备更强的抗噪性能,并且提取的边缘线条比其余边缘检测算法更加清晰、完整,保留了更多的纹理细节信息。(2)在客观指标评价的对比上,与基于分数阶灰色系统模型的边缘检测算法以及改进的分数阶Sobel边缘检测算法相比,Lif算法在Entropy指标上分别提高了43%、11%,AG指标上分别提高了23%、23%,SSIM指标上分别提高了152%、6%。表明Lif算法在进行采煤机截割部的边缘检测任务时更具优势,研究对井下设备工作运行时的安全性和可靠性提升具有重要意义。

关键词：低照度图像分数阶微分边缘检测采煤机截割部煤矿