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New indices to balanceα-diversity against tree size inequality

Journal of Forestry Research 2024年第1期35卷 229-237页

作者： Li Zhang Brady K.Quinn cang hui Meng Lian Johan Gielis Jie Gao Peijian Shi College of Ecology and Environment Bamboo Research InstituteNanjing Forestry University159 Longpan RoadNanjing 210037People’s Republic of China Fisheries and Oceans Canada Andrews Biological Station125 Marine Science DriveSt.AndrewsNB E5B 0E4Canada Department of Mathematical Sciences Centre for Invasion BiologyStellenbosch UniversityMatieland 7602South Africa Mathematical and Physical Biosciences African Institute for Mathematical SciencesCape Town 7945South Africa Department of Biosciences Engineering University of AntwerpB-2020 AntwerpBelgium College of Life Science Xinjiang Normal University102 Xinyi RoadUrumqi 830054People’s Republic of China

The number and composition of species in a community can be quantified withα-diversity indices,including species richness(R),Simpson’s index(D),and the Shannon-Wiener index(H΄).In forest communities,there are large variations in tree size among species and individu-als of the same species,which result in differences in eco-logical processes and ecosystem ***,tree size inequality(TSI)has been largely neglected in studies using the available diversity *** TSI in the diameter at breast height(DBH)data for each of 99920 m×20 m forest census quadrats was quantified using the Gini index(GI),a measure of the inequality of size *** generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per *** also examined the relationships ofα-diversity indices with the GI using correlation *** generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions,with most root-mean-square errors(990 out of 999 quadrats)being<*** were significant positive correlations between each of threeα-diversity indices(i.e.,R,D,and H’)and the ***,the total abundance of trees in each quadrat did not significantly influence the *** means that the TSI increased with increasing spe-cies ***,two new indices are proposed that can balanceα-diversity against the extent of TSI in the com-munity:(1−GI)×D,and(1−GI)×H’.These new indices were significantly correlated with the original D and H΄,and did not increase the extent of variation within each group of *** study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities,especially in the face of cumulative species loss under global climate change.

关键词： Diameter at breast height(DBH) Gini index Shannon-Wiener index Simpson’s index Quadrat Tree size

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Quantifying multiple-site compositional turnover in an Afrotemperate forest, using zeta diversity

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Forest Ecosystems 2018年第2期5卷 189-197页

作者： cang hui Wessel Vermeulen Graham Durrheim Centre for Invasion Biology Department of Mathematical SciencesStellenbosch University Mathematical and Physical Biosciences African Institute for Mathematical Sciences Garden Route Scientific Services South African National Parks

Background： Species turnover is typically measured by partitioning diversity components into alpha and pairwise beta diversity. However, alpha and beta components cannot express the full spectrum of multiple-site compositional turnover. To this end, zeta diversity has been proposed as an extended framework to allow complete biodiversity partitioning and to measure multiple-site species turnover. We use a zeta-diversity framework to explore the turnover and potential community assembly processes of an African Montane Forest. Methods： Using a 20 m grid, we explore the species turnover in a 4.55 ha forest plot located in the Garden Route National Park of South Africa, with 47 and 27 canopy and sub-canopy tree species in the regional poo We first calculate how zeta diversity declines and how the probability of retention of species with particular occupancies changes with increasing zeta orders （i.e. the number of sites [grid cells] involved in the calculation）. Using null models with row sums and column sums constrained respectively, we explore whether species turnover is driven by mechanisms of ecological differences （species-specific occupancies） or habitat heterogeneity （site-specific alpha diversity and thus environmental filters）. Results： The decline of zeta diversity with zeta order followed a power law; that is, the probability of retention increased with species occupancies, suggesting common species being more likely to be discovered in extra sites. The null model retaining row sums （species＇ occupancy） of the species-by-site matrix recreated perfectly the decline of zeta diversity, while the null model of habitat heterogeneity （retaining column sums） was rejected. This suggests that mechanisms driving species-specific occupancies （i.e. ecological differences between species） dictate the multi-site species turnover in the community. The spatial patterns of zeta diversity revealed little spatial structuring forces, supporting a fine-grain structure in these sou

关键词： Species turnover Diversity partitioning Zeta diversity Community assembly Southern cape forest Afromontane forest

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Finish line plant-insect interactions mediated by insect feeding mode and plant interference： a case study of Brassica interactions with diamondback moth and turnip aphid

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Insect Science 2018年第4期25卷 690-702页

作者： Mahmoud Soufbaf Yaghoub Fathipour Jeffrey A. Harvey cang hui Department of Entomology Faculty of Agriculture Tarbiat Modares University Tehran Iran Department of Terrestnal Ecology Netherlands Institute of Ecology Wageningen the Netherlands Section Animal Ecology Department of Ecological Sciences VU University Amsterdam Amsterdam the Netherlands Department of Mathematical Sciences Centre for Invasion Biology Stellenbosch University Matieland South Africa Mathematical and Physical Biosciences African Institute for Mathematical Sciences Cape Town South Africa

There are gaps in our understanding of plant responses under different insect phytophagy modes and their subsequent effects on the insect herbivores＇ performance at late season. Here we compared different types of insect feeding by an aphid, Lipaphis erysimi, and a lepidopteran, Plutella xylostella, and how this affected defensive metabolites in leaves of 2 Brassica species when plants gain maturity. Thiocyanate concentrations after P xylostella and L. erysimi feeding activities were the same. Total phenolics was higher after the phloem feeder feeding than the folivore activity. The plants compensatory responses （i.e., tolerance） to L. erysimi feeding was significantly higher than the responses to P xylostella. This study showed that L. erysirni had higher carbon than P xylostella whereas nitrogen in P xylostella was 1.42 times that in L. erysimi. Population size of the phloem feeder was not affected by plant species or insect coexistence. However, there was no correlation between plant defensive metabolites and both insects＇ population size and biomass. This suggests that plant root biomass and tolerance index after different insect herbivory modes are not necessarily unidirectional. Importantly, the interaction between the folivore and the phloem feeder insects is asymmetric and the phloem feeder might be a trickier problem for plants than the folivore. Moreover, as both plants＇ common and special defenses decreased under interspecific interference, we suggest that specialist insect herbivores can be more challenged in ecosystems in which plants are not involved in interspecific interference.

关键词： glucosinolates herbivory mode plant resistance stoichiometric analysis tolerance

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Modeling the transmission of Buruli ulcer in fluctuating environments

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International Journal of Biomathematics 2017年第5期10卷 45-67页

作者： Belthasara Assan Farai Nyabadza Pietro Landi cang hui Department of Mathematical Sciences Stellenbosch University Private Bag X1 Matieland Cape Town 7602 South Africa African Institute for Mathematical Sciences (AIMS) Cape Town 7945 South Africa

The transmission dynamics of Buruli ulcer （BU） largely depends on environmental changes. In this paper a deterministic model for the transmission of BU in fluctuating environments is proposed. The model incorporates periodicity in the disease transmission pathways and the Mycobacterium ulcerans density that are thought to vary seasonally. Two reproduction numbers, the time-averaged reproduction number [R0l and the basic reproduction number R0, are determined and compared. It is shown that the time-averaged reproduction underestimates the number of infections. Numerical simulations confirmed that if R0 〉 1 the infection is sustained seasonally. The model outcome suggests that environmental fluctuations should be taken into consideration in designing policies aimed at BU control and management.

关键词： Buruli ulcer time-averaged reproduction number basic reproduction number extinction persistence.

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Synthesis and Crystal Structure of a New Organic-inorganic Hybrid One-dimensional Polymer: [Zn(C_8H_(23)N_5)]_2(Pb_3I_(10))

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Chinese Journal of Structural Chemistry 2005年第6期24卷 679-683页

作者： YERuo-Bai HUANGChang-cang ZHANGHan-hui LIHao-Hong YANGQi-Yu SUNRui-Qing DepartmentofChemistryandKeyLaboratoryofChemistryofSolidMaterials FuzhouUniversityFuzhouFujian350002China

A new organic-inorganic hybrid coordinated polymer [Zn(C8H23N5)]2(Pb3I10) (C8H23N5 = tetraethylene pentamine) was synthesized by hydrothermal reaction. It crystallizes in triclinic, space group P1 with a = 9.781(2), b = 11.442(3), c = 11.565(3) ?, α = 99.075(8), β = 90.540(9), γ = 109.967(5)o, Zn2C16H46N10Pb3I10, Mr = 2399.94, V = 1198.4(5) ?3, Z = 1, Dc = 3.325 g/cm3, F(000) = 1048.0, μ(MoKα) = 17.951 mm-1, the final R = 0.0412 and wR = 0.0993 for 3375 observed reflections with I > 2σ(I). The title compound consists of [Zn(C8H23N5)]2+ cations and anionic chains [Pb3I10]n4n-, which are combined with each other via electrostatic attractive forces and N–H…I hydrogen bonds.

关键词： polymeric complex iodoplumbate crystal structure chain-like structure

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BET法测定勃姆石比表面积的研究

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广州化工 2024年第15期52卷 85-87页

作者：马卫丹仓向辉王开爱中铝郑州有色金属研究院有限公司河南郑州450041

采用不同的预处理温度、预处理时间和相对压力等条件,对勃姆石的比表面积进行测定,并依据建立的数学模型,分析不确定度产生的来源,对各不确定度分量和扩展不确定度进行计算。结果表明,测量勃姆石比表面积的最佳预处理温度为110℃,处理... 详细信息

采用不同的预处理温度、预处理时间和相对压力等条件,对勃姆石的比表面积进行测定,并依据建立的数学模型,分析不确定度产生的来源,对各不确定度分量和扩展不确定度进行计算。结果表明,测量勃姆石比表面积的最佳预处理温度为110℃,处理时间为3 h,BET单点法相对压力取值为0.20。测量不确定度主要来自于单层饱和吸附量的测定和仪器校准,勃姆石试样的比表面积为3.89 m^(2)/g,扩展不确定度为0.36 m^(2)/g。

关键词：勃姆石比表面积不确定度

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气顶边底水油藏开发后期见水规律分析及对策

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内蒙古石油化工 2024年第6期50卷 121-124页

作者：王宁仓辉宋强曹卿荣余若愚刘柯陕西延长石油(集团)有限责任公司研究院陕西西安710075 延长油田股份有限公司定边采油厂陕西延安718600

气顶边底水油藏在注水开发后期,由于气窜、边底水、注入水、套损等多重因素的影响,造成的高含水关停井不断增加,本次研究中主要对油藏天然能量重新评价、对关停井原因分类分析、剩余潜力分布再认识,通过注水开发井网调整、注水参数优化... 详细信息

气顶边底水油藏在注水开发后期,由于气窜、边底水、注入水、套损等多重因素的影响,造成的高含水关停井不断增加,本次研究中主要对油藏天然能量重新评价、对关停井原因分类分析、剩余潜力分布再认识,通过注水开发井网调整、注水参数优化、关停井治理等方面研究,制定出不同见水类型针对性治理对策,提高了注水波及体积,见到了一定的增油降水效果。在研究过程中首次对优势通道类型甄别及治理对策进行了总结归纳,为今后同类型油藏调驱堵水及综合治理提供了技术参考。

关键词：气顶边底水天然能量评价关停井分析见水类型井网调整调驱井优选

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一种简易牵引装置在结肠内镜黏膜下剥离术中的临床应用(含视频)

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中华消化内镜杂志 2024年第5期41卷 405-407页

作者：王文平冷霞仓慧刘华敏刘鹏飞孙岳军王芳军南通大学附属江阴医院消化内科江阴214400

评估在结肠内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)中,金属夹联合丝线和橡皮圈作为简易内牵引装置的临床应用价值。以2021年1月至2022年7月间,在南通大学附属江阴医院进行ESD治疗的56例早期结肠癌和癌前病变患者为研... 详细信息

评估在结肠内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)中,金属夹联合丝线和橡皮圈作为简易内牵引装置的临床应用价值。以2021年1月至2022年7月间,在南通大学附属江阴医院进行ESD治疗的56例早期结肠癌和癌前病变患者为研究对象,采用计算机软件随机分配,分为常规ESD治疗的对照组(n=28)和金属夹联合丝线及橡皮圈牵引的牵引组(n=28)。对两组患者的ESD手术总时间、黏膜剥离时间、黏膜下注射次数、完整切除病灶率、手术并发症等情况进行综合比较。结果牵引组手术总时间较对照组短[(74.64±33.25)min比(117.18±35.75)min,t=4.61,P0.05)。可见,金属夹联合丝线及橡皮圈的作为牵引辅助装置,可以降低结肠ESD的技术难度,缩短手术时间。

关键词：结肠肿瘤牵引内镜黏膜下剥离术金属夹

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New indices to balance α-diversity against tree size inequality

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林业研究（英文版） 2024年第1期 233页

作者： Li Zhang Brady K.Quinn cang hui Meng Lian Johan Gielis Jie Gao Peijian Shi

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Variation in individual biomass decreases faster than mean biomass with increasing density of bamboo stands

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Journal of Forestry Research 2020年第3期31卷 981-987页

作者： Guohua Liu cang hui Ming Chen Lauren SPile GGeoff Wang Fusheng Wang Peijian Shi Co-Innovation Centre for Sustainable Forestry in Southern China Bamboo Research InstituteNanjing Forestry UniversityNanjing 210037People’s Republic of China Department of Mathematical Sciences Centre for Invasion BiologyStellenbosch UniversityMatieland 7602South Africa Mathematical and Physical Biosciences African Institute for Mathematical SciencesCape Town 7945South Africa USDA Forest Service Sierra National Forest—High Sierra Ranger DistrictPratherCA 93651USA Department Forestry and Environmental Conservation Clemson UniversityClemsonSC 29634USA

The total biomass of a stand is an indicator of stand productivity and is closely related to the density of plants. According to the self-thinning law, mean individual biomass follows a negative power law with plant density. If the variance of individual biomass is constant, we can expect increased stand productivity with increasing plant density. However, Taylor's power law(TPL) that relates the variance and the mean of many biological measures(e.g. bilateral areal differences of a leaf, plant biomass atdifferent times, developmental rates at different temperatures, population densities on different spatial or temporal scales), affects the estimate of stand productivity when it is defined as the total biomass of large plants in a *** the variance of individual biomass decreases faster than mean individual biomass, differences in individual biomass decline with increasing density, leading to more homogeneous timbers of greater economic value. We tested whether TPL in plant biomass holds for different species and whether the variance of individual biomass changes faster than the mean with increasing stand *** height, ground diameter and fresh weight of 50 bamboo species were measured in 50 stands ranging from 1 m by 1 m to 30 m by 30 m to ensure more than 150 bamboos in every stand. We separately examined TPL in height,ground diameter, and weight, and found that TPL holds for all three biological measures, with the relationship strongest for weight. Using analysis of covariance to compare the regression slopes of logarithmic mean and variance against the logarithm of density, we found that the variance in individual biomass declined faster than the mean with increasing density. This suggests that dense planting reduced mean individual biomass but homogenized individual biomass. Thus, there exists a trade-off between effective stand productivity and stand density for optimal forest management. Sparse planting leads to large variation in individual bi

关键词： Bamboo Linear fitting Self-thinning law Taylor's power law Variance

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