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Habitat heterogeneity and biotic interactions mediate climate influences on seedling survival in a temperate forest

Forest Ecosystems 2023年第5期10卷 579-588页

作者： Haikun Liu Hang Shi Quan Zhou Man Hu Xiao Shu kerong zhang Quanfa zhang Haishan Dang Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan430074China University of Chinese Academy of Sciences Beijing100049China

Seedling stage has long been recognized as the bottleneck of forest regeneration,and the biotic and abiotic processes that dominate at seedling stage largely affect the dynamics of forest.Seedlings might be particularly vulnerable to climate stress,so elucidating the role of interannual climate variation in fostering community dynamics is crucial to understanding the response of forest to climate change.Using seedling survival data of 69 woody species collected for five consecutive years from a 25-ha permanent plot in a temperate deciduous forest,we identified the effects of biotic interactions and habitat factors on seedling survival,and examined how those effects changed over time.We found that interannual climate variations,followed by biotic interactions and habitat conditions,were the most significant predictors of seedling survival.Understory light showed a positive impact on seedling mortality,and seedling survival responded differently to soil and air temperature.Effects of conspecific neighbor density were significantly strengthened with the increase of maximum air temperature and vapor pressure deficits in the growing season,but were weakened by increased maximum soil temperature and precipitation in the non-growing season.Surprisingly,seedling survival was strongly correlated with interannual climate variability at all life stages,and the strength of the correlation increased with seedling age.In addition,the importance of biotic and abiotic factors on seedling survival differed significantly among species-trait groups.Thus,the neighborhood-mediated effects on mortality might be significantly contributing or even inverting the direct effects of varying abiotic conditions on seedling survival,and density-dependent effects could not be the only important factor influencing seedling survival at an early stage.

关键词： Seedling survival Extreme interannual climate Negative density-dependence Species coexistence

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Patterns of species diversity and its determinants in a temperate deciduous broad-leaved forest

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Forest Ecosystems 2022年第5期9卷 647-656页

作者： Rui He Man Hu Hang Shi Quan Zhou Xiao Shu kerong zhang Quanfa zhang Haishan Dang Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan430074China University of Chinese Academy of Sciences Beijing100049China

Biodiversity conservation has long been a subject of extreme interest to community ecologists,with a particular focus on exploring the underlying causes of species diversity based on niche and neutral theories.This study aims to identify the potential determinants of species diversity in a deciduous broad-leaved forest in the transitional region from subtropical to temperate climate in China.We collected woody plant data and environmental variables in a fully mapped 25-ha permanent forest plot,partitioned the beta-diversity into local contributions(LCBD)and species contributions(SCBD),and then applied multivariate linear regression analysis to test the effects of biotic and abiotic factors on alpha-diversity,LCBD,and SCBD.We used variation partitioning in combination with environmental variables and spatial distance to determine the contribution of environment-related variations versus spatial variations.Our results showed that the indices of alpha-diversity(i.e.,species abundance and richness)were positively correlated with soil available phosphorus(P)and negatively with slope.For the betadiversity,environment and space together explained nearly half of the variations in community composition.Approximately 60%of the variation of LCBD in the understory layer,40%in the substory layer,and 29%in the canopy layer were jointly explained by topographic,soil and biological variables,with biotic factors playing a dominant role in determining the beta-diversity.Species abundance accounted for a large proportion of the variations in SCBD in each vertical stratum,and niche position(NP)was the ecological trait that significantly affected the variations in SCBD in the substory and canopy layers.Our findings help to gain better understanding on how species diversity in forest ecosystem responds to environmental conditions and how it is influenced by biotic factors and ecological traits of species.

关键词： Alpha-diversity Beta-diversity Vertical strata Multivariate linear regression

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Regeneration dynamics of subalpine fir (Abies fargesii) forest across the altitudinal range in the Shennongjia Mountains, central China

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Journal of Plant Ecology 2013年第1期6卷 36-47页

作者： Haishan Dang kerong zhang Yanjun zhang Xunzhang Tong Quanfa zhang Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074People’s Republic of China

Aims Age structure and regeneration dynamics have been used to infer population response to environmental events and reconstruct forest development history.The aim of this study was to characterize and examine the differences of the age structure and regeneration dynamics of subalpine fir(Abies fargesii)forest across the altitudinal range in the north and south aspects in the Shennongjia Mountains,central China.Methods Ten plots(20×20 m)at each altitudinal zone(i.***.the low elevation,the middle elevation and the high elevation)were established in both the north and south aspects of the Shennongjia Mountains,central China.Dendroecological techniques were applied to obtain information about ages of the trees in the plots.The population age structure was analyzed to investigate the regeneration dynamics across the altitudinal range.Important findings Fir regeneration dynamics and age structure were similar in both aspects,and a unimodal population age structure was found at different altitudinal sites of both aspects,indicating that environmental factors might play an important role in shaping the regeneration dynamics and age structure of A.fargesii across its altitudinal range.There was a sustained recruitment during the 19th century,but the regeneration was rarer in the last century at low and midelevations.A significant greater number of fir seedlings and saplings recruited at high elevations in the last century,and fir tree density at high elevations was significantly higher than that at low elevations.Thus,the fir population at the high elevations showed a significant increase in recruitment and stem density in the last century,and we propose that the gradual infilling of fir seedlings might result in changes in regeneration dynamics and stand structure of the subalpine fir forest at high elevations in the Shennongjia Mountains,central China.

关键词： regeneration dynamics age structure Abies fargesii the Shennongjia Mountains

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Spatial–temporal variability of terrestrial vegetation productivity in the Yangtze River Basin during 2000–2009

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Journal of Plant Ecology 2014年第1期7卷 10-23页

作者： Yulong zhang Conghe Song kerong zhang Xiaoli Cheng Quanfa zhang Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of Sciences1 Moshan RoadWuhan 430074China Department of Geography University of North Carolina209 South RoadChapel HillNC 27599USA Department of Life Science University of the Chinese Academy of Sciences19 Yuquan RoadBeijing 100049China School of Forestry and Landscape Architecture Anhui Agricultural University130 West Changjiang RoadHefeiAnhui 230026China

Aims Terrestrial net primary production(NPP),the balance of gross primary production(GPP)and autotrophic respiration(AR),is a critical measure of carbon sequestration capacity for the Earth’s land surface.The aim of this study was to understand the spatio-temporal variability of NPP associated with GPP and AR in the Yangtze River Basin(YRB),China,from 2000 to 2009 during which the basin warmed significantly.Methods We first derived AR and carbon-use efficiency(CUE)from the improved Moderate Resolution Imaging Spectroradiometer GPP/NPP products(MOD17)and then conducted spatial analysis to quantify how NPP relates to GPP,AR and their relationship with key observed climate variables(temperature,precipitation and sunshine percentage)in the YRB during 2000–2009.Important Findings The spatial pattern of NPP in the YRB was predominantly determined by GPP and further modified by AR.Higher GPP and relatively low AR made the southern Jinshajiang sub-basin the most productive area in NPP in the YRB.A large portion of the YRB experienced a warmer and drier climate trend in the growing season during 2000–2009.In the upper reaches of the basin,possessing a relatively low temperature base,increases in temperature led to greater increases in GPP than those in AR,resulting in greater increased NPP.However,in the middle and lower reaches of the basin where the base temperature is relatively high,increases in temperature led to greater increases in AR than those in GPP,leading to decreases in NPP.Overall,86.7%of the vegetated area showed a consistent GPP and NPP trend through time with 71.3%of the vegetated area having a positive trend both in GPP and NPP,and the remaining 13.3%of vegetated areas showed an opposite trend in GPP and NPP,with positive GPP and negative NPP trajectories dominating(10.1%of vegetated area)the trend.Although climate warming generally had positive effects on vegetation growth in most areas of the basin,areas with increased NPP(74.5%)were less extensive than those with increased GPP(81.4%)due to the wider i

关键词： Yangtze River Basin climate warming GPP AR NPP CUE spatial-temporal variability

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微晶玻璃固结磨料研磨加工亚表面损伤预测研究

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表面技术 2024年第2期53卷 158-167页

作者：王科荣宗傲牛凤丽张羽斐朱永伟南京航空航天大学机电学院南京210016 南京航空航天大学江苏省精密与微细制造技术重点实验室南京210016 金华职业技术学院机电工程学院浙江金华321000

目的快速、准确预测微晶玻璃在研磨加工过程中的亚表面损伤状况,制定合理的加工工艺。方法通过建立微晶玻璃的离散元模型,仿真分析了研磨压力等研磨工艺参数对工件亚表面损伤的影响规律,并采用角度抛光法对研磨后微晶玻璃的亚表面损... 详细信息

目的快速、准确预测微晶玻璃在研磨加工过程中的亚表面损伤状况,制定合理的加工工艺。方法通过建立微晶玻璃的离散元模型,仿真分析了研磨压力等研磨工艺参数对工件亚表面损伤的影响规律,并采用角度抛光法对研磨后微晶玻璃的亚表面损伤状况进行了实验验证。结果采用W14金刚石固结磨料垫研磨微晶玻璃,当研磨压力为10 kPa时,工件亚表面裂纹层深度为1.75μm,当研磨压力降低至3.5 kPa时,工件亚表面裂纹层深度为1.38μm;随着研磨压力的降低,亚表面微裂纹数量减少。研磨残余应力层分布深度大于微裂纹层的,且在微裂纹的尖端存在较大的残余拉应力。结论角度抛光法得到的亚表面裂纹层深度与仿真结果一致,偏差范围为-10.87%~11.29%,残余应力仿真结果与试验结果的偏差为7.89%。离散元仿真能够比较准确地预测固结磨料研磨微晶玻璃的亚表面损伤状况,为其研磨抛光工艺参数的制定提供了理论参考依据。

关键词：微晶玻璃固结磨料研磨亚表面损伤残余应力离散元仿真

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质量风险视角下的电网物资供应商履约行为分析与对策研究

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上海管理科学 2024年第1期46卷 108-113页

作者：李钊汤颖丽夏宁泽张可融国网湖北省电力有限公司湖北武汉430077 国网湖北物资公司湖北武汉430010 同济大学经济与管理学院上海200092

国家电网配网物资供应链中的产品质量对于配电网的安全运行具有非常重要的意义,其质量风险监控是电网企业的重要管理难题。基于企业实际检测运行数据,构建了相应的供应商履约行为分析模型,并基于实证研究探索了供应商非诚信履约行为与... 详细信息

国家电网配网物资供应链中的产品质量对于配电网的安全运行具有非常重要的意义,其质量风险监控是电网企业的重要管理难题。基于企业实际检测运行数据,构建了相应的供应商履约行为分析模型,并基于实证研究探索了供应商非诚信履约行为与物资原材料价格之间的动态关联,发现原材料价格的增长型波动并不必然导致供应商的不诚信履约,利润空间总变动小或单位利润空间占比低对于供应商的履约行为有重要的指示性意义,进而在此基础上建立了相应的配网物资供应商非诚信行为预警模型。在数字化转型背景下,这一分析结果有助于为企业精准风控和运营管理提供新的思路与对策。

关键词：供应商履约质量风险国家电网配网物资

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妊娠期阴道微生态的研究现状

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中外女性健康研究 2024年第3期 38-40页

作者：乔志莉廖祥余李崇敏张科荣川北医学院附属医院妇产科四川南充637000

女性阴道是一个由阴道内的微生物菌群、宿主的内分泌系统、阴道解剖结构及局部免疫系统共同组成的动态微环境。当阴道菌群、宿主及环境之间相互作用的动态平衡被打破,就可能引起一系列的疾病。妊娠又是一个复杂并且动态变化的生理过程,... 详细信息

女性阴道是一个由阴道内的微生物菌群、宿主的内分泌系统、阴道解剖结构及局部免疫系统共同组成的动态微环境。当阴道菌群、宿主及环境之间相互作用的动态平衡被打破,就可能引起一系列的疾病。妊娠又是一个复杂并且动态变化的生理过程,可能影响阴道微生态的平衡,导致出现不良妊娠结局。本文对非妊娠和妊娠女性阴道微生态的特点和影响因素进行综述,旨在对预防妊娠期阴道微生态失衡提供一定的参考。

关键词：妊娠期阴道微生态影响因素

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硝普钠对谷子烯禾啶药害的缓解效应

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植物保护 2024年第2期50卷 137-143页

作者：武茜张世芳王馨茹苏新宇樊珂荣慕泽男王育选赵娟山西农业大学农学院太谷030801 山西农业大学软件学院太谷030801

为了解硝普钠是否可以缓解除草剂烯禾啶对谷子的药害,本试验以谷子优质品种‘晋谷21号’愈伤组织为试验材料,将不同浓度硝普钠与烯禾啶复配后添加到培养基中对其进行胁迫处理,观察不同处理下愈伤组织的生长情况,并分别测定其抗氧化酶活... 详细信息

为了解硝普钠是否可以缓解除草剂烯禾啶对谷子的药害,本试验以谷子优质品种‘晋谷21号’愈伤组织为试验材料,将不同浓度硝普钠与烯禾啶复配后添加到培养基中对其进行胁迫处理,观察不同处理下愈伤组织的生长情况,并分别测定其抗氧化酶活性,渗透调节物质含量等相关生理指标,通过分析比较这些指标在不同处理间的差异,了解硝普钠对烯禾啶药害的缓解效应,并对其解毒机制进行初步探讨。结果表明,硝普钠对谷子烯禾啶药害有一定缓解作用,且缓解作用随烯禾啶处理浓度而发生变化,硝普钠浓度需根据烯禾啶浓度进行调整。硝普钠与烯禾啶复配提高了愈伤组织细胞抗氧化酶活性和渗透调节物质含量,减轻烯禾啶对谷子的损伤。本研究为生产中使用硝普钠减轻谷子烯禾啶药害提供了一定的理论依据。

关键词：谷子愈伤组织硝普钠烯禾啶缓解药害

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安徽省能源、经济与生态环境三大系统耦合协调发展研究

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西安文理学院学报（自然科学版） 2024年第1期27卷 117-124页

作者：金燕芝张克荣王思元姜亮宇阜阳师范大学商学院安徽阜阳236000

为推进能源、经济与生态环境相互融合、协调发展,采用改进熵值法测算2016—2020年安徽省16个地级市能源、经济与生态环境系统综合发展值,并采用耦合协调度模型评价各系统间协调发展水平.得出结论:2016—2020年间三大系统综合发展水平为... 详细信息

为推进能源、经济与生态环境相互融合、协调发展,采用改进熵值法测算2016—2020年安徽省16个地级市能源、经济与生态环境系统综合发展值,并采用耦合协调度模型评价各系统间协调发展水平.得出结论:2016—2020年间三大系统综合发展水平为生态环境系统>经济系统>能源系统,三大系统耦合协调度呈“上升-下降”状态,其中经济与生态环境协调度最高.从演变格局来看,能源与经济耦合协调发展呈现“皖北>皖南”格局,其中皖南地区呈“U型”发展;经济与生态环境协调发展呈现安徽省中部城市低于其相邻城市的分布特征,并且高耦合协调度城市由皖南地区逐步向北扩散.能源与生态环境耦合协调发展呈现“皖北>皖中>皖南”格局,其中皖北地区呈现波动式上升趋势.

关键词：能源经济生态环境综合发展水平耦合协调度

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功能近红外光谱在癫痫中的应用及研究进展

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昆明医科大学学报 2024年第5期45卷 178-183页

作者：朱琳李依陈科容张永花施红伶云南省第三人民医院康复医学科云南昆明650011

功能近红外光谱学(functional near-infrared spectroscopy,fNIRS)被广泛应用于神经病学的研究,癫痫是其中之一。通过联合脑电图(electroencephalogram,EEG)监测,能够完整的监测到痫性发作过程,有助于进一步研究癫痫的病理生理机制。此... 详细信息

功能近红外光谱学(functional near-infrared spectroscopy,fNIRS)被广泛应用于神经病学的研究,癫痫是其中之一。通过联合脑电图(electroencephalogram,EEG)监测,能够完整的监测到痫性发作过程,有助于进一步研究癫痫的病理生理机制。此外,fNIRS还能够辅助癫痫灶定位、语言侧化中枢评估,为癫痫的临床诊疗提供帮助。就fNIRS在癫痫中的应用及研究进展进行回顾,以期对后续的研究提供参考。

关键词：癫痫功能近红外光谱致痫灶语言侧化

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