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Microbial community diversity analysis of <i>Panax ginseng</i>rhizosphere and non-rhizosphere soil using randomly amplified polymorphic DNA method 被引量:3
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作者 Yong Li Yixin Ying +1 位作者 Dongyue Zhao Wanlong Ding 《Open Journal of Genetics》 2012年第2期95-102,共8页
DNA sequence diversities of soil microbial communities in rhizosphere and non-rhizosphere of 1 - 6 years Panax ginseng were evaluated by random amplified polymorphic DNA (RAPD). Total genomic DNA of soil samples were ... DNA sequence diversities of soil microbial communities in rhizosphere and non-rhizosphere of 1 - 6 years Panax ginseng were evaluated by random amplified polymorphic DNA (RAPD). Total genomic DNA of soil samples were amplified by twenty-four out of two hundred random primers. The products were separated in agarose gel, and 359 and 181 reliable fragments were generated, of which, 324 and 123 were polymorphic. The gene diversity index, Shannon’s information index, and similarity coefficient were calculated, and results showed that, diversity of soil microbial community at DNA level was present. Furthermore, with the increasing of P. ginseng growing at one site, deference on soil microbial community DNA sequence between rhizosphere and non-rhizosphere tend to be more and more significant. In addition, RAPD technique was proved to be an effective tool to assess the diversity of soil microbial communities. From results we deduced that, the ecological function that performed by soil microbes may changed following the change of microbial community in rhizospheric and non-rhizospheric soils, and finally broke the balance of soil nutrition and energy cycle, soil spatial structure, microbial ecology etc. 展开更多
关键词 p. GINSENG MICROBIAL Community Genetic diversity RHIZOSpHERE Soil
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Phylogeography and Cryptic Species Diversity of Paramesotriton caudopunctatus Species Group(Salamandridae: Paramesotriton) in Guizhou, China 被引量:2
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作者 Tao LUO Huamei WEN +2 位作者 Kai GAO Jun ZHOU Jiang ZHOU 《Asian Herpetological Research》 SCIE CSCD 2021年第2期188-200,共13页
The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary rel... The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal. 展开更多
关键词 p.caudopunctatus species group pHYLOGEOGRApHY cryptic diversity BIOGEOGRApHY species delimitation GUIZHOU
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耦合优化蚁群算法与P-Median model的选址模型设计
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作者 顾梓程 胡新玲 《现代电子技术》 北大核心 2024年第3期109-114,共6页
为节省城建部门对于公共体育设施的投入成本以及提高城市人民生活质量,以运动场所优化选址为例,提出一种新型设施选址模型。该模型主要基于P-Median model(最小化阻抗模型)根据需求点数量从全部候选设施选址中选择设施空间位置,让用户... 为节省城建部门对于公共体育设施的投入成本以及提高城市人民生活质量,以运动场所优化选址为例,提出一种新型设施选址模型。该模型主要基于P-Median model(最小化阻抗模型)根据需求点数量从全部候选设施选址中选择设施空间位置,让用户达到离自己最近设施距离成本总和最小的目的,对选址的基本原则和实际情况提出要求,构造目标函数用于优化后蚁群算法求解进行选址工作。优化蚁群算法实现基于Python语言模块,通过改进蚁群原始信息素,提升原有算法的收敛速度,求出目标函数最优解,可以很好地模拟对于运动场所的选址。用二者耦合进行优势互补所设计的选址模型来搜寻研究区蚁群信息素浓度残留最大的栅格像元,从而确定未被已有设施点服务半径覆盖的最佳设施点建立位置。实验结果表明,该新型选址模型相较于最小化阻抗模型与最大化覆盖模型,新增优化设施点使整体服务半径覆盖率分别高出10.42%和6.95%,适合求解较为精确且小规模空间下的选址问题。 展开更多
关键词 蚁群算法 p-Median model 选址模型 GIS 运动场所 位置分配 pYTHON
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Effects of Vegetation Restoration Age on Soil C:N:P Stoichiometry in Yellow River Delta Coastal Wetland of China
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作者 CAO Qixue WANG Xiajie +7 位作者 CHU Xiaojing ZHAO Mingliang WANG Lianjing SONG Weimin LI Peiguang ZHANG Xiaoshuai XU Shendong HAN Guangxuan 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1045-1059,共15页
Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this s... Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this study,we examined the re-sponses of soil C,N,and P contents and their stoichiometric ratios to vegetation restoration age,focusing on below-ground processes and their relationships to aboveground vegetation community characteristics.We conducted an analysis of temporal gradients based on the'space for time'method to synthesize the effects of restoration age on soil C:N:P stoichiometry in the Yellow River Delta wetland of China.The findings suggest that the combined effects of restoration age and soil depth create complex patterns of shifting soil C:N:P stoichiometry.Specifically,restoration age significantly increased all topsoil C:N:P stoichiometries,except for soil total phosphorus(TP)and the C:N ratio,and slightly affected subsoil C:N:P stoichiometry.The effects of restoration age on the soil C:N ratio was well constrained owing to the coupled relationship between soil organic carbon(SOC)and total nitrogen(TN)contents,while soil TP con-tent was closely related to changes in plant species diversity.Importantly,we found that the topsoil C:N:P stoichiometry was signific-antly affected by plant species diversity,whereas the subsoil C:N:P stoichiometry was more easily regulated by pH and electric con-ductivity(EC).Overall,this study shows that vegetation restoration age elevated SOC and N contents and alleviated N limitation,which is useful for further assessing soil C:N:P stoichiometry in coastal restoration wetlands. 展开更多
关键词 coastal wetland restoration age soil C:N:p stoichiometry soil properties plant species diversity Yellow River Delta of China
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Species,growth form,and biogeographic diversity of summit vegetation along an elevation gradient in the tropical Andes:a baseline for climate change monitoring
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作者 Luis D.LLAMBI Luis E.GAMEZ +6 位作者 Roxibell PELAYO Carmen J.AZOCAR Jesus E.TORRES Nelson J.MARQUEZ Monica B.BERDUGO Francisco CUESTA Lirey A.RAMIREZ 《Journal of Mountain Science》 SCIE CSCD 2022年第12期3441-3457,共17页
Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species compositio... Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species composition,richness and community structure along tropical alpine altitudinal gradients is of primary importance,both the functional and historical/biogeographic dimensions of vegetation diversity remain largely unexplored.We used Generalized Linear Models and multivariate analyses to assess changes in species,growth forms,and biogeographic groups richness and abundance,in response to habitat variables along an elevation gradient in seven summits(3800 to 4600 m asl)in the Venezuelan Andes,studied using the standardized approach of the GLORIA-Andes monitoring network.The habitat variables assessed were soil temperature(-10 cm),soil organic matter,slope inclination,and substrate cover.We found 113 species,representing72 genera,32 families,13 growth forms,and seven biogeographic origins,that included 25%of endemic elements.We observed richer vegetation,both in terms of species and growth forms,in summits with higher soil temperatures and higher SOM content,as well as higher biogeographic origin richness with increasing soil temperatures.The presence of holarctic elements increased toward higher elevations,while the occurrence of austral antarctic elements increased toward lower elevations.Our results indicate that biogeographic and functional approaches to vegetation diversity capture well the effect of abiotic filtering on community structuring in these tropical alpine environments.These findings constitute an important baseline for monitoring vegetation dynamics linked to climate change in the Venezuelan Andes by highlighting the functional and historical perspective on vegetation analyses,in contrast with more traditional approaches,based only on taxonomic species diversity. 展开更多
关键词 Alpine vegetation BIOGEOGRApHY Elevation gradient Functional diversity páramo Soil organic matter Temperature Tropical Andes
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NT4p53(N15)Ant重组腺病毒对肝癌细胞腹腔种植瘤的治疗作用 被引量:2
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作者 吴学元 白斌 +1 位作者 张党锋 马巍 《西安交通大学学报(医学版)》 CAS CSCD 北大核心 2014年第1期73-76,107,共5页
目的研究NT4p53(N15)Ant融合基因重组腺病毒预先感染ICR小鼠腹腔后,对肝癌细胞株H22腹腔种植瘤的治疗作用。方法将16只ICR小鼠随机平均分成2组,分别于腹腔内预先感染Ad-NT4p53(N15)Ant(治疗组)及等量空病毒(对照组)。将H22细胞悬液接种... 目的研究NT4p53(N15)Ant融合基因重组腺病毒预先感染ICR小鼠腹腔后,对肝癌细胞株H22腹腔种植瘤的治疗作用。方法将16只ICR小鼠随机平均分成2组,分别于腹腔内预先感染Ad-NT4p53(N15)Ant(治疗组)及等量空病毒(对照组)。将H22细胞悬液接种于小鼠腹腔,建立小鼠腹腔泛发性种植瘤模型。根据小鼠生长情况、生存期以及腹水瘤细胞形态、细胞凋亡率和小鼠腹腔内瘤体重量等结果,评价Ad-NT4p53(N15)Ant对H22细胞种植瘤及癌性腹水的治疗效果。结果成功构建了小鼠腹腔泛发性种植瘤动物模型。与对照组相比,Ad-NT4p53(N15)Ant组小鼠生存期延长、腹水的产生时间延迟,腹水中多核巨细胞减少,细胞凋亡及坏死的比率升高,腹腔内瘤体的质量减少。结论 Ad-NT4p53(15)Ant可有效抑制H22肝癌细胞腹腔移植瘤生长,延迟腹水形成,诱导体内腹水瘤细胞凋亡及坏死,延长小鼠生存期。 展开更多
关键词 NT4p53(N15)ant 重组腺相关病毒 肝癌 凋亡 癌转移 腹水
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NT4p53(N15)Ant融合基因重组腺病毒的构建及其体外抑瘤作用 被引量:1
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作者 宋丽萍 李跃萍 +3 位作者 邱曙东 黄辰 王爱英 李围围 《癌症》 SCIE CAS CSCD 北大核心 2008年第2期144-148,共5页
背景与目的:有研究发现P53氨基端15肽与穿膜肽(antennapedia,Ant)的融合肽能迅速穿透细胞膜,直接、快速引起乳腺癌、胰腺癌细胞坏死而非凋亡,但对正常细胞几乎没有毒性。本研究构建缺陷型腺病毒载体表达NT4p53(N15)Ant融合基因,研究其... 背景与目的:有研究发现P53氨基端15肽与穿膜肽(antennapedia,Ant)的融合肽能迅速穿透细胞膜,直接、快速引起乳腺癌、胰腺癌细胞坏死而非凋亡,但对正常细胞几乎没有毒性。本研究构建缺陷型腺病毒载体表达NT4p53(N15)Ant融合基因,研究其体外抑瘤作用。方法:应用Ad-EasyTM系统,在大肠杆菌同源重组,构建NT4p53(N15)Ant腺病毒表达载体,在HEK-293细胞内成功包装并鉴定后,感染肝癌细胞株HepG2,用倒置相差显微镜、透射电镜观察细胞形态学变化、四甲基偶氮唑蓝(MTT)比色实验及培养基中的乳酸脱氢酶(lactatedehydrogenase,LDH)测定研究其体外抑瘤作用。结果:Ad-NT4p53(N15)Ant对肝癌细胞株HepG2有明显抑制作用,48、72、96h细胞存活率分别为36.67%、20.47%、17.82%,与空病毒处理组比较差异有统计学意义(P<0.05);电镜观察到感染的HepG2细胞胞膜、核膜破坏,胞浆内出现囊泡状物质,染色质聚集。Ad-NT4p53(N15)Ant处理HepG2细胞24、48、72、96h时培养液中LDH释放分别为94、236、267、313U/L,较空病毒处理组明显增加,其差异有统计学意义(P<0.05)。结论:构建的腺病毒载体Ad-NT4p53(N15)Ant感染HepG2细胞后能抑制细胞增殖。 展开更多
关键词 NT4p53(N15)ant 腺病毒载体 肿瘤 基因治疗
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重组腺相关病毒-NT4p53(C22)Ant对肝癌荷瘤小鼠的治疗作用 被引量:1
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作者 周琦 纪宗正 《南方医科大学学报》 CAS CSCD 北大核心 2007年第9期1355-1357,1367,共4页
目的研究NT4p53(C22)Ant重组腺相关病毒(rAAV)对肝癌荷瘤小鼠的治疗作用。方法构建NT4p53(C22)Ant,将其亚克隆于重组腺相关病毒载体中,经293细胞包装、扩增构成具有感染性的rAAV-NT4p53(C22)Ant,将小鼠源的H22肿瘤细胞接种于ICR小鼠皮下... 目的研究NT4p53(C22)Ant重组腺相关病毒(rAAV)对肝癌荷瘤小鼠的治疗作用。方法构建NT4p53(C22)Ant,将其亚克隆于重组腺相关病毒载体中,经293细胞包装、扩增构成具有感染性的rAAV-NT4p53(C22)Ant,将小鼠源的H22肿瘤细胞接种于ICR小鼠皮下,成瘤后根据瘤体质量、抑制率、动物生存时间及病理组织学结果,评价rAAV-NT4p53(C22)Ant治疗肝癌细胞(H22)的移植瘤作用。结果一次性肿瘤局部注射NT4p53(C22)Ant重组腺相关病毒100μl/次(2×1011pfu/ml)接种于ICR荷瘤小鼠皮下的H22肝癌细胞,12只小鼠7只瘤块消失,1只死亡,瘤体的质量明显减小,生存时间大于70d;而对照组中,7只小鼠均死亡,死亡率100%,生存时间约为30d,较治疗组明显缩短。治疗组肿瘤抑制率大于90%,较未治疗和注射空病毒对照组有显著性差异,组织学观察rAAV-NT4p53(C22)Ant治疗组较对照组肿瘤细胞明显减少。结论NT4p53(C22)Ant重组腺相关病毒可以有效地杀伤小鼠体内的H22肝癌细胞,诱导肿瘤细胞凋亡,抑制肿瘤生长,生存期延长。 展开更多
关键词 NT4p53(C22)ant 重组腺相关病毒 肝癌 荷瘤小鼠
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NT4p53(C22)Ant重组腺伴病毒对人Miapaca-Ⅱ胰腺癌细胞的杀伤作用
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作者 周琦 纪宗正 《第四军医大学学报》 CAS 北大核心 2006年第22期2054-2056,共3页
目的:研究NT4p53(C22)Ant重组腺伴病毒对人M iapaca-Ⅱ胰腺癌细胞杀伤作用.方法:构建NT4p53(C22)Ant,将其亚克隆于腺伴病毒载体中,经293细胞包装、扩增构成具有感染性的重组腺伴病毒AAV-NT4p53(C22)Ant,转染人胰腺癌M iapaca-Ⅱ细胞,经... 目的:研究NT4p53(C22)Ant重组腺伴病毒对人M iapaca-Ⅱ胰腺癌细胞杀伤作用.方法:构建NT4p53(C22)Ant,将其亚克隆于腺伴病毒载体中,经293细胞包装、扩增构成具有感染性的重组腺伴病毒AAV-NT4p53(C22)Ant,转染人胰腺癌M iapaca-Ⅱ细胞,经光镜下观察、MTT比色试验、PI染色实验及乳酸脱氢酶释放检测(LDH),观察AAV-NT4p53(C22)Ant对细胞的杀伤作用.结果:光镜下可见随AAV-NT4p53(C22)Ant感染Miapaca-Ⅱ细胞时间延长,肿瘤细胞数目明显减少;MTT实验检测发现细胞存活率明显降低(P<0.05);流式细胞检测凋亡细胞数目较对照组及空病毒组增加(P<0.05);LDH检测培养基中LDH只有轻度增加(P>0.05).结论:重组腺伴病毒NT4p53(C22)Ant对胰腺癌细胞有杀伤作用,并且是通过引起细胞凋亡而实现的. 展开更多
关键词 NT4p53(C22)ant 重组腺伴病毒 胰腺肿瘤 细胞系
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Response of ants to grazing disturbance at the central Monte Desert of Argentina: community descriptors and functional group scheme 被引量:1
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作者 Silvia CLAVER Susana L SILNIK Florencia F CAMPóN 《Journal of Arid Land》 SCIE CSCD 2014年第1期117-127,共11页
Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants... Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants are good biological indicators due to the environmental fidelity of some of their community parameters.We described the functional structure of the ant community in the central Monte of Mendoza,Argentina,and examined the effect of grazing using richness,diversity and the functional group scheme.We used pitfall traps to sample ants at a reserve with 30-year cattle exclusion and at an adjacent ranch.Eleven of the 27 recorded species showed significant differences in their abundance and two species were absent at the ranch.While richness and diversity did not reflect these differences,functional groups did.Hot Climate Specialists were more abundant at the ranch while Cryptic Species and Generalized Myrmicinae increased at the reserve.This study supports the utility of the functional group scheme to study the effects of grazing disturbance in ant communities of arid regions. 展开更多
关键词 ants cattle grazing functional groups richness diversity arid zones Monte Desert
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Ants Assemblage Method According to an Age Gradient of Mango Orchards in Korhogo (C&ocirc;te d’Ivoire)
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作者 Tra Bi Crolaud Sylvain Soro Senan +5 位作者 Kouakou Lombart Yeboue Lucie Yacouba Hanna-Thérèse Bissiri Yeo Kolo Konate Souleymane Tano Yao 《Advances in Entomology》 2020年第1期56-71,共16页
This study was conducted in the Korhogo region in an age gradient of mango orchards. The goal was to assess diversity and determine the influence of the environment on the composition of these organisms. Sampling was ... This study was conducted in the Korhogo region in an age gradient of mango orchards. The goal was to assess diversity and determine the influence of the environment on the composition of these organisms. Sampling was done using pitfall traps, threshing and manual collection. A total of 82 ant species were sampled on all plots. The cultivated plots are richer in ant species than the natural environment. Of the three (3) sampling methods, the Manual Collection proved to be more efficient (eff = 79.52%), followed by threshing (eff = 75.15%) and finally the least effective trap pit (eff = 73.39%). The number of individuals of the species varies according to the environment. The highest value was obtained in the young plot (485 individuals), followed by the intermediate plot (478 individuals), then the older plot (426 individuals) and finally the control plot (320 individuals). The species Camponotus acvapimensis was harvested mainly with 159 individuals. On the other hand, the species Lepisiota sp.1;Camponotus rufigenis, Camponotus sericeus and Oecophylla longinoda were specifically harvested in the control, young, intermediate and aged plots, respectively. 展开更多
关键词 ant MANGO TREE Age GRADIENT ASSEMBLAGE diversity
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A Routing Algorithm for Risk-Scanning Agents Using Ant Colony Algorithm in P2P Network
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作者 TANG Zhuo LU Zhengding LI Ruixuan 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1097-1103,共7页
This paper describes a routing algorithm for risk scanning agents using ant colony algorithm in P2P(peerto peer) network. Every peer in the P2P network is capable of updating its routing table in a real-time way, wh... This paper describes a routing algorithm for risk scanning agents using ant colony algorithm in P2P(peerto peer) network. Every peer in the P2P network is capable of updating its routing table in a real-time way, which enables agents to dynamically and automatically select, according to current traffic condition of the network, the global optimal traversal path. An adjusting mechanism is given to adjust the routing table when peers join or leave. By means of exchanging pheromone intensity of part of paths, the algorithm provides agents with more choices as to which one to move and avoids prematurely reaching local optimal path. And parameters of the algorithm are determined by lots of simulation testing. And we also compare with other routing algorithms in unstructured P2P network in the end. 展开更多
关键词 RISK ant colony algorithm p2p
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State of Art of Ants (Hymenoptera: Formicidae) at Caxiuanã, Melgaco, Pará, Brazil
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作者 Ana Yoshi Harada 《Advances in Entomology》 2016年第3期115-132,共18页
The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the know... The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place. 展开更多
关键词 ants Amazonia diversity Richness
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State of Art of Ants (Hymenoptera: Formicidae) at Caxiuanã, Melgaco, Pará, Brazil
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作者 Ana Yoshi Harada 《Advances in Entomology》 2016年第3期115-132,共18页
The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the know... The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place. 展开更多
关键词 ants Amazonia diversity Richness
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常绿阔叶林植物叶片N、P化学计量特征对毛竹扩张的响应
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作者 王琳 欧阳明 +6 位作者 宋述望 曾小霞 宋庆妮 刘骏 方熊 栾丰刚 杨清培 《广西植物》 CAS CSCD 北大核心 2023年第9期1737-1746,共10页
为从生态化学计量内平衡角度解释常绿阔叶林不同层次植物对毛竹(Phyllostachys edulis)扩张的生存响应差异性,该研究采用空间代替时间的方法,在江西井冈山国家级自然保护区沿毛竹扩张方向选取典型毛竹-常绿阔叶林界面,依次设置毛竹林、... 为从生态化学计量内平衡角度解释常绿阔叶林不同层次植物对毛竹(Phyllostachys edulis)扩张的生存响应差异性,该研究采用空间代替时间的方法,在江西井冈山国家级自然保护区沿毛竹扩张方向选取典型毛竹-常绿阔叶林界面,依次设置毛竹林、竹阔混交林和常绿阔叶林样地,比较分析了毛竹扩张方向上样地内不同乔木层、灌木层、草本层植物叶片及土壤N、P含量及比例。结果表明:(1)从毛竹林到阔叶林,土壤N含量上升,P含量下降,N∶P上升(P<0.05);乔木层树种[红楠(Machilus thunbergii)、赤杨叶(Alniphyllum fortunei)及交让木(Daphniphyllum macropodum)]叶片P含量下降,N∶P上升(P<0.05);除灌木层的红果山胡椒(Lindera erythrocarpa)外,各林分中的灌木层和草本层植物N、P含量及比例变化较小。(2)土壤N∶P与乔木层、草本层和灌木层植物叶片N∶P分布呈显著正相关、负相关与不相关。(3)在各林分中,毛竹叶片N、P含量及比例较稳定。综上认为,毛竹通过改变土壤N、P化学计量特征进行扩张,引起植物体N、P元素化学计量特征发生变化。灌木及草本植物受土壤异质性影响较小,但是乔木层植物N、P元素化学计量特征却因此失衡,这可能是阔叶林乔木层树种存亡受威胁的重要原因。 展开更多
关键词 毛竹扩张 植物多样性 生态化学计量内平衡 土壤N∶p 江西井冈山国家级自然保护区
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腾格里沙漠东南缘固沙植被区蚁丘对中小型土壤节肢动物群落的影响
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作者 周磊 刘任涛 曾飞越 《生态学报》 CAS CSCD 北大核心 2024年第20期9252-9263,共12页
为阐明固沙植被区中蚂蚁筑巢活动形成蚁丘对中小型土壤节肢动物群落的影响规律,于2022年在腾格里沙漠东南缘建植第5、8、34、57年的固沙植被区中,分别采集蚁丘内、外土壤样品,采用干漏斗法分离中小型土壤节肢动物,调查了固沙植被演替过... 为阐明固沙植被区中蚂蚁筑巢活动形成蚁丘对中小型土壤节肢动物群落的影响规律,于2022年在腾格里沙漠东南缘建植第5、8、34、57年的固沙植被区中,分别采集蚁丘内、外土壤样品,采用干漏斗法分离中小型土壤节肢动物,调查了固沙植被演替过程中蚁丘内外中小型土壤节肢动物群落组成、多样性分布特征及影响因素。结果显示:(1)中小型土壤动物的优势类群包括球角虫兆属、等节虫兆属和小真古螨科,分别从第8、34、57年开始呈现出蚁丘内显著高于蚁丘外的分布特征(P<0.05)。中小型土壤节肢动物优势类群个体数及总个体数均从固沙植被建植第8年开始,蚁丘内显著高于蚁丘外(P<0.05)。(2)中小型土壤动物群落类群数和Shannon-Wiener指数均表现为从固沙植被建植第34年开始,表现为蚁丘内显著高于蚁丘外(P<0.05),而且34年固沙植被区蚁丘内分别是蚁丘外的1.6倍、2.2倍,57年固沙植被区蚁丘内分别是蚁丘外的2.3倍、3.9倍;均匀度指数仅在固沙57年呈现出蚁丘内显著高于蚁丘外(P<0.05)的分布特征,即蚁丘内是蚁丘外的5.4倍。(3)结构方程模型显示,在固沙初期,土壤黏粒含量是影响中小型土壤节肢动物群落分布的主要环境因子,而在中后期则为土壤全氮和全钾含量。综合分析表明,腾格里沙漠东南缘固沙植被演替初期蚁丘仅增加中小型土壤节肢动物个体数,而只有在长期演替后蚁丘才表现为显著增加其个体数和多样性、直至改变群落组成结构,并对裸沙地中小型土壤节肢动物个体数分布具有重要辐射作用。 展开更多
关键词 中小型土壤节肢动物 群落多样性 固沙植被区 生态系统演替 蚁丘 腾格里沙漠
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缙云山森林土壤速效P的分布特征及其与物种多样性的关系研究 被引量:42
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作者 杨万勤 钟章成 陶建平 《生态学杂志》 CAS CSCD 北大核心 2001年第4期24-27,共4页
Distribution characteristics of soil phosphorus availability and its correlations with plant species diversity in the forest ecosystem of Mt.Jinyun are studied in this paper.The results are as follows:①Available P of... Distribution characteristics of soil phosphorus availability and its correlations with plant species diversity in the forest ecosystem of Mt.Jinyun are studied in this paper.The results are as follows:①Available P of soil profile in different communities has an evident gradient,i.e.,A(humus layer)>B(deposition layer)>C(parent material layer).②Except for shrub-grassland,soil available P content orderly increases along the successional directions,i.e.,Pinus massoniana forest<P.massonia-Symplocos setchuensis mixed forest<evergreen broadleaved forest.③Different degree’s of correlations exist between soil available P and plant species diversity.The correlation between tree diversity and available P content of A and B layers is very significant. 展开更多
关键词 缙云山 重庆 森林土壤 速效p 分布特征 物种多样性
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大针茅种群RAPD多样性及其与若干生态因子的相关关系 被引量:22
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作者 赵念席 高玉葆 +2 位作者 王金龙 任安芝 徐华 《生态学报》 CAS CSCD 北大核心 2006年第5期1312-1319,共8页
利用RAPD分子标记,对锡林郭勒草原主要建群种大针茅(StipagrandisP.Smirn.)5个种群共90个基因株的遗传多样性进行了分析。由16个10碱基随机引物共扩增得到310条清晰可重复的RAPD片段,且全部为多态性条带。利用POPGENE软件对RAPD数据进... 利用RAPD分子标记,对锡林郭勒草原主要建群种大针茅(StipagrandisP.Smirn.)5个种群共90个基因株的遗传多样性进行了分析。由16个10碱基随机引物共扩增得到310条清晰可重复的RAPD片段,且全部为多态性条带。利用POPGENE软件对RAPD数据进行分析可以看出,不同地理种群大针茅存在很高的遗传变异,且大部分变异存在于种群之内,只有少量变异存在于种群之间(≈28%)。Pearson相关分析表明,大针茅种群内基因多样性与温度因子(≥10℃年积温、年均温和1月份均温)之间存在显著(p<0·05)或极显著(p<0·01)的相关关系;Mantel检验结果显示,大针茅种群间的遗传距离与种群间的实际地理距离之间不存在显著的相关关系(r=0·184,p=0·261),但与水热因子的分异之间存在显著(p<0·05)或极显著(p<0·01)的相关关系。这些都表明水热差异的自然选择引起大针茅种群RAPD标记的生态地理分化,而迁移和遗传漂变对大针茅种群间的分化不起决定作用。 展开更多
关键词 大针茅 建群种 RApD 遗传多样性 气候因子 自然选择
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苎麻疫霉群体的RAPD分析 被引量:16
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作者 王建营 郑小波 《菌物系统》 CSCD 北大核心 2003年第2期228-234,共7页
利用从126个RAPD(RandomAmplifiedPolymorphicDNAs)随机引物中筛选到的可扩增出清晰条带、主带明显、稳定的8条引物,对采集自江苏、安徽和江西不同寄主的45个Phytophthoraboehmeriae菌株进行全基因组DNARAPD标记遗传多样性分析。选用引... 利用从126个RAPD(RandomAmplifiedPolymorphicDNAs)随机引物中筛选到的可扩增出清晰条带、主带明显、稳定的8条引物,对采集自江苏、安徽和江西不同寄主的45个Phytophthoraboehmeriae菌株进行全基因组DNARAPD标记遗传多样性分析。选用引物共标出DNA指纹图带68条,其中多态性条带20条,多态性检测率为29.4%,表明该种内不同地区和寄主来源的菌株间变异较小。利用Popgene软件计算供试菌株间的遗传距离并绘制聚类树状图,供试菌株被划分为2个遗传聚类组。菌株间的遗传相似性与菌株的寄主来源有一定的相关性,来自江苏、江西和安徽棉花上的27个菌株被划分在同一遗传聚类组内,而分离自构树、枫杨和苎麻的18个菌株被划分在另一个遗传聚类组。结果还表明菌株间遗传相似性与其地区来源无直接相关性。 展开更多
关键词 苎麻疫霉 RApD 遗传多样性 遗传相似性
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N-对甲苯磺酰β-丙氨酸稀土(Pr、Yb)一维链配合物的合成、晶体结构及抑菌活性 被引量:3
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作者 马录芳 王利亚 +3 位作者 杜仲祥 梁福沛 张漫波 郁开北 《应用化学》 CAS CSCD 北大核心 2005年第3期246-249,共4页
合成了N 对甲苯磺酰β 丙氨酸与稀土Pr3+离子和Yb3+离子的配合物,并进行了元素分析及红外光谱表征。测定了 2个配合物的晶体结构。配合物组成为 [Ln2 (H2O)4 (Ts -β -Ala- )6 ]n·4nH2O(Ln为Pr(1)、Yb(2),Ts -β- Ala-为N 对甲苯... 合成了N 对甲苯磺酰β 丙氨酸与稀土Pr3+离子和Yb3+离子的配合物,并进行了元素分析及红外光谱表征。测定了 2个配合物的晶体结构。配合物组成为 [Ln2 (H2O)4 (Ts -β -Ala- )6 ]n·4nH2O(Ln为Pr(1)、Yb(2),Ts -β- Ala-为N 对甲苯磺酰β- 丙氨酸阴离子 ),配合物属单斜晶系,P21 /n空间群;晶胞参数:配合物(1):a=0. 953 2(3)nm,b=1 .909 5(6)nm,c=2. 298 0(8)nm,β=99. 73(2)°;配合物(2):a=0 .956 9(1)nm,b=1 888 0(3)nm,c=2. 286 8(3)nm,β=100 .41(1)°。配合物 (1)和 (2)均为无限一维链结构,但链中羧基桥连方式不同;Pr3+为 9配位而Yb3+为 8配位。抑菌实验表明,配合物的抑菌效果明显好于配体。 展开更多
关键词 对甲苯磺酰β-丙氨酸 稀土配合物 晶体结构 抑菌活性
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