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Spatial patterns of insect herbivory within a forest landscape:the role of soil type and forest stratum

Forest Ecosystems 2021年第4期8卷 923-936页

作者： xinliang shao Qin Zhang Xitian Yang Key Laboratory of Plant Genetics and Molecular Breeding Zhoukou Normal University466001 ZhoukouChina College of Forestry Henan Agricultural University450002 ZhengzhouChina

Background:Insect herbivory has profound impacts on ecosystem processes and *** many efforts have been made to recognize the main drivers of insect herbivory at different scales,the results are *** likely reason is that studies have insufficiently captured the spatially heterogeneous factors such as soil type and forest stratum within the stand that may significantly affect insect *** particular,there is a lack of studies that address the detailed spatial patterns of insect herbivory which are influenced by these ***:We measured the detailed spatial patterns of insect herbivory on cork oak(Quercus variabilis Bl.)in response to soil type(gravel soil and loam)and forest stratum(the upper,lower,and sapling stratum),and correlated these patterns with a set of influencing factors(litter coverage,coverage of shrubs and herbs,soil nutrients,soil moisture,and leaf traits)in a forest ***:Generally,insect herbivory was spatially heterogeneous within *** was significantly lower in gravel soil areas than in loam soil areas and the highest herbivory occurred in the lower ***,there were also 41 individual plots in which the highest herbivory occurred in the upper stratum and 29 plots in which the highest herbivory occurred in the sapling *** were significant differences in soil nutrient and water status between soil types,but no significant differences in leaf *** effects of forest stratum on leaf traits were also inconsistent with those on insect ***:Leaf traits may not be the main factors influencing insect herbivory in the *** type may have major effects on herbivory patterns by influencing litter coverage while higher coverage of shrubs and herbs may reduce herbivory in the sapling *** findings may advance our understanding of tree-herbivore interactions in real-world situations and have important implications for the sustainable managemen

关键词： Forest stratum Heterogeneity Insect herbivory Leaf litter Leaf traits Soil nutrient Soil type

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Effects of tree diversity on insect herbivory

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Journal of Forestry Research 2022年第2期33卷 391-396页

作者： xinliang shao Ke Cheng Yuhua Kong Qin Zhang Xitian Yang College of Forestry Henan Agricultural UniversityZhengzhou 450002People’s Republic of China Zhengzhou Yaoling Technology Co. Ltd.Zhengzhou 450000People’s Republic of China

Tree diversity has long been considered a key driver of insect herbivory in forest ***,studies have given contradictory results:increased tree diversity can have positive,negative or neutral effects on insect *** many issues can complicate the tree-herbivore interactions,the descriptor‘tree diversity’per se actually has only limited explanatory power for insect ***,in addition to the direct bottom-up effects on insect herbivores,tree diversity may have stronger indirect top-down effects via natural enemies of insect ***,most research has addressed only direct bottom-up *** fact,insect herbivory is the result of complex interactions(food webs)among all the species in a *** it is hard to integrate all functionally important species and dynamic information into food webs,the effects of tree diversity on insect herbivory are highly dependent on the dominant species at different trophic *** is important and practical to simultaneously consider the characteristics of main trees,herbivores,and natural enemies when attempting to predict the overall effects of forest tree diversity on insect *** order to ensure comparability between studies,it is necessary to classify them according to the descriptors of insect herbivory and tree diversity,and to compare results within each *** measures might enhance our understanding of the mechanisms by which tree diversity drives insect herbivory and,in turn,help to develop sustainable pest management strategies for forests.

关键词： Enemy diversity Food webs Sustainable pest management Tree diversity Tree-herbivore interactions

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Grassland degradation in the ＂Three-River Headwaters＂ region, Qinghai Province

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Journal of Geographical Sciences 2008年第3期18卷 259-273页

作者： LIU Jiyuan XU xinliang shao Quanqin Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Supported by MSS images in the mid and late 1970s,TM images in the early 1990s and TM/ETM images in 2004,grassland degradation in the＂Three-River Headwaters＂region （TRH region）was interpreted through analysis on RS images in two time series,then the spatial and temporal characteristics of grassland degradation in the TRH region were analyzed since the *** results showed that grassland degradation in the TRH region was a continuous change process which had large affected area and long time scale,and rapidly strengthen phenomenon did not exist in the 1990s as a *** degradation pattern in the TRH region took shape initially in the mid and late *** the 1970s,this degradation process has taken place continuously,obviously characterizing different rules in different *** humid and semi-humid meadow region,grassland firstly fragmentized, then vegetation coverage decreased continuously,and finally＂black-soil-patch＂degraded grassland was *** in semi-arid and arid steppe region,the vegetation coverage decreased continuously,and finally desertification was *** grassland degradation had obviously regional differences in the TRH region,it could be regionalized into 7 zones, and each zone had different characteristics in type,grade,scale and time process of grassland degradation.

关键词： "Three-River Headwaters" region Qinghai grassland degradation remote sensing spatial pattern temporal process

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Effects of an ecological conservation and restoration project in the Three-River Source Region, China

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Journal of Geographical Sciences 2017年第2期27卷 183-204页

作者： shao Quanqin CAO Wei FAN Jiangwen HUANG Lin XU xinliang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

The first-stage of an ecological conservation and restoration project in the Three-River Source Region（TRSR）, China, has been in progress for eight years. However, because the ecological effects of this project remain unknown, decision making for future project implementation is hindered. Thus, in this study, we developed an index system to evaluate the effects of the ecological restoration project, by integrating field observations, remote sensing, and process-based models. Effects were assessed using trend analyses of ecosystem structures and services. Results showed positive trends in the TRSR since the beginning of the project, but not yet a return to the optima of the 1970 s. Specifically, while continued degradation in grassland has been initially contained, results are still far from the desired objective, ‘grassland coverage increasing by an average of 20%–40%＇. In contrast, wetlands and water bodies have generally been restored, while the water conservation and water supply capacity of watersheds have increased. Indeed, the volume of water conservation achieved in the project meets the objective of a 1.32 billion m^3 increase. The effects of ecological restoration inside project regions was more significant than outside, and, in addition to climate change projects, we concluded that the implementation of ecological conservation and restoration projects has substantially contributed to vegetation restoration. Nevertheless, the degradation of grasslands has not been fundamentally reversed, and to date the project has not prevented increasing soil erosion. In sum, the effects and challenges of this first-stage project highlight the necessity of continuous and long-term ecosystem conservation efforts in this region.

关键词： Three-River Source Region ecological conservation and restoration ecosystem monitoring and assessment ecological effects

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Ultra-broadband pulse generation via hollow-core fiber compression and frequency doubling for ultra-intense lasers

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High Power Laser Science and Engineering 2023年第1期11卷 38-43页

作者： Yanyan Li Beijie shao Yujie Peng Junyu Qian Wenkai Li xinliang Wang Xingyan Liu Xiaoming Lu Yi Xu Yuxin Leng Ruxin Li State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-intense Laser Science Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)ShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina

We demonstrate an ultra-broadband high temporal contrast infrared laser source based on cascaded optical parametric amplification,hollow-core fiber(HCF)and second harmonic generation *** this setup,the spectrum of an approximately 1.8μm laser pulse has near 1μm full bandwidth by employing an argon gas-filled ***,after frequency doubling with cascaded crystals and dispersion compensation by a fused silica wedge pair,9.6 fs(~3cycles)and 150μJ pulses centered at 910 nm with full bandwidth of over 300 nm can be *** energy stability of the output laser pulse is excellent with 0.8%(root mean square)over 20 min,and the temporal contrast is>10^(12)at-10 ps before the main *** excellent temporal and spatial characteristics and stability make this laser able to be used as a good seed source for ultra-intense and ultrafast laser systems.

关键词： few-cycle laser high temporal contrast ultra-broadband ultrafast laser

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基于WinCC和串口通讯的炉温监控系统设计

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仪表技术与传感器 2013年第12期 58-60,63页

作者：张新良杜韶河南理工大学电气工程与自动化学院河南焦作454000

文中给出了利用WinCC组态软件和串口通讯方式,进行电加热炉炉温监控系统设计的具体实现方案。选用热电偶作为温度传感器测量电加热炉的温度,利用曲线拟合的方法得到热电偶分度表的电动势-温度关系,给出了一种改进的补偿冷端电压的方法,... 详细信息

文中给出了利用WinCC组态软件和串口通讯方式,进行电加热炉炉温监控系统设计的具体实现方案。选用热电偶作为温度传感器测量电加热炉的温度,利用曲线拟合的方法得到热电偶分度表的电动势-温度关系,给出了一种改进的补偿冷端电压的方法,避免使用查表方式,提高了测量精度。上位计算机监控系统基于WinCC组态软件构建,使用Windows的MSCOMM控件实现与下位单片机的串口通讯,并给出了程序的关键代码。同时,设计了一种带有引导码的串口通讯方式,保证了数据的准确、快速传输。实验结果表明,该系统运行稳定、可靠,具有实际的应用价值。

关键词： MSCOMM控件热电偶串口通讯曲线拟合电加热炉 WinCC

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基于改进的两步移动搜索法的山区医疗服务空间可达性——以重庆市石柱县为例

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地理科学进展 2015年第6期34卷 716-725页

作者：邓丽邵景安郭跃徐新良重庆师范大学地理与旅游学院重庆400047 三峡库区地表过程与环境遥感重庆市重点实验室重庆400047 资源与环境信息系统国家重点实验室中国科学院地理科学与资源研究所北京100101

针对贫困山区医疗资源短缺、分布不均衡、服务能力差等问题,以重庆市石柱县为例,基于自然村尺度,采用改进的两步移动搜索法,从供需角度分析研究区医疗服务空间可达性特征。设置不同的时间阻抗进行敏感性分析,探究可达性变化规律。通过... 详细信息

针对贫困山区医疗资源短缺、分布不均衡、服务能力差等问题,以重庆市石柱县为例,基于自然村尺度,采用改进的两步移动搜索法,从供需角度分析研究区医疗服务空间可达性特征。设置不同的时间阻抗进行敏感性分析,探究可达性变化规律。通过对石柱县医疗资源空间布局的均衡性评价,为山区未来医疗布局的合理规划与医疗标准的配备提供决策依据。结果表明:1石柱县整体医疗服务可达性差,低于重庆市平均水平。2县域医疗资源布局不均衡,空间差异明显。高值区主要集中在方斗山中低山区和黄水镇,低值区主要集中在南部中山区,两极分异明显。3医院的规模、级别,道路的等级、疏密对可达性有一定的影响:靠近县城的乡镇、路网密集的地方可达性一般较好。4随着出行阻抗的增大,医疗服务的可达性随之变好,边缘乡镇的可达性随之变差,可达性值变化幅度减缓,医疗服务空间可达性分异变小;医疗资源配备充足的乡镇,随着时间阻抗增加,对周边乡镇可达性的影响增强。

关键词：贫困山区医疗服务改进的两步移动搜索法空间可达性敏感性重庆

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基于熵权-TOPSIS的山区乡镇通达性研究--以重庆市石柱县为例

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地理科学进展 2016年第9期35卷 1144-1154页

作者：马雪莹邵景安徐新良重庆师范大学地理与旅游学院重庆400047 三峡库区地表过程与环境遥感重庆市重点实验室重庆400047 中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101

交通是支撑区域经济社会发展的基础之一,通达性则是反映交通设施水平的有效评价指标。本文以重庆市石柱县为例,选取空间数据和调研数据,引入熵权-TOPSIS模型构建集内外通达性和摩擦阻抗于一体的指标体系,客观分析山区乡镇的通达性,以期... 详细信息

交通是支撑区域经济社会发展的基础之一,通达性则是反映交通设施水平的有效评价指标。本文以重庆市石柱县为例,选取空间数据和调研数据,引入熵权-TOPSIS模型构建集内外通达性和摩擦阻抗于一体的指标体系,客观分析山区乡镇的通达性,以期为交通合理规划提供参考。结果表明:(1)通达性指标对区域综合通达性影响程度为:交通设施技术(C_4)>摩擦阻抗(C_5)>等效道路密度(C_2)>乡镇内部连通度(C_1)>与省干道衔接度(C_3)。(2)贴近度变异系数达0.5410,说明样区交通通达性水平空间差异大。(3)通达性空间格局表现出以南宾、西沱、悦崃为极核点向外围扩散递减趋势;通达性空间分布表现为西高东低,高通达区主要分布在平缓区,低通达区主要分布在陡峭山区。(4)通达性良好区域呈"一环一轴"模式分布,呈显著主干道指向性。(5)样区乡镇通达性空间分布格局与经济发展水平和土地流转面积有较高趋同性。研究结果能为区域协调发展、交通合理规划提供良好的理论与实践指导。

关键词：交通通达性空间变异通道—阻隔效应熵权-TOPSIS 山区重庆石柱县

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结构和工况参数对动压滑动轴承润滑性能影响的研究

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轴承 2018年第9期 29-33页

作者：邵钢胡新亮孙军中国船舶重工集团公司第七○三研究所哈尔滨150078 合肥工业大学机械工程学院合肥230009 合肥工业大学汽车与交通工程学院合肥230009

在动压滑动轴承润滑分析基础上,应用正交试验设计法,研究结构参数(轴承直径、宽径比和间隙比)和工况参数(线速度和比压)对动压滑动轴承润滑性能的影响。结果表明:线速度和比压对轴承最大油膜压力影响显著,比压和轴承直径对轴承承载力影... 详细信息

在动压滑动轴承润滑分析基础上,应用正交试验设计法,研究结构参数(轴承直径、宽径比和间隙比)和工况参数(线速度和比压)对动压滑动轴承润滑性能的影响。结果表明:线速度和比压对轴承最大油膜压力影响显著,比压和轴承直径对轴承承载力影响显著,轴承直径和线速度对轴承端泄流量影响显著;低黏度润滑剂下线速度对轴承摩擦功耗影响最为显著,高黏度润滑剂下间隙比、比压和轴承直径对轴承摩擦功耗影响变大。

关键词：动压滑动轴承结构参数工况参数润滑性能

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山区乡村学校空间格局演变特征及发展水平

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地理研究 2016年第3期35卷 455-470页

作者：赵晨旭邵景安郭跃徐新良重庆师范大学地理与旅游学院重庆400047 三峡库区地表过程与环境遥感重庆市重点实验室重庆400047 资源与环境信息系统国家重点实验室中国科学院地理科学与资源研究所北京100101

作为农村基础设施的乡村学校在工业化、城镇化的快速推进过程中正在面临极为严峻的形势。利用趋势面分析、空间热点探测分析、核密度估计、主成分分析、聚类分析等方法对2004-2014年山区乡村学校空间格局演变特征及发展水平进行实证分析... 详细信息

作为农村基础设施的乡村学校在工业化、城镇化的快速推进过程中正在面临极为严峻的形势。利用趋势面分析、空间热点探测分析、核密度估计、主成分分析、聚类分析等方法对2004-2014年山区乡村学校空间格局演变特征及发展水平进行实证分析,结果表明:1乡村学校的规模总体上大幅减少,尤其是学校的数量减少最为明显,减少接近一半(49.0%)。学校的高集聚区分布于沿江平坝区和两山所夹槽谷区,而两山区相对较低。2不同类型区乡村学校的服务范围显著缩小,特别是丘陵区2014年较2004年服务半径缩小62.0%,其次是低山区缩小47.2%。3乡村学校发展表现出空间变化较为强烈的相对不协调情景,由2004年发展的不均匀、不合理变为2014年的正常合理发展。4乡村学校的变化具有显著地正向空间集聚现象,整体呈随机分布状态,现已形成一个以西南部南宾镇为中心的大面积热点区和东南向以新乐、金玲和金竹为代表的低值区。5研究区乡村学校的发展可分为:基础差—衰落区、基础好—衰落区、基础差—发展区和基础好—发展区,这一格局与地形、经济、交通区位等对教育资源的分配影响有很大关系。6未来研究区乡村学校的发展方略应着重考虑优化乡村学校的布局,适时引导适龄儿童的家庭就近就地迁移,强调中心校、"大校"和"名校"建设。在山区人口大规模流动的背景下,明确现阶段和未来的发展思路和策略,对指导山区乡村学校发展有重要意义。

关键词：乡村学校空间格局演变特征发展水平山区

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