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1.
2012年7月29日在内蒙古大兴安岭西坡汗马国家级自然保护区野外考察时,记录到1只松雀(Pinicola enucleator)。经查阅文献和检视标本,发现该种在中国实际已有若干春夏季的分布记录。该种已知在某些年份具有爆发式迁徙的习性,繁殖期和越冬期分布范围的年际变化很大。根据上述记录,推测松雀在国内的分布状况除以往所认知的冬候鸟而外,还应是罕见的夏候鸟。而在四川金城山地区的松雀记录实际应为红眉松雀(P.subhimachala)。  相似文献   

2.
干旱胁迫下4种常用植物幼苗的光合和荧光特性综合评价   总被引:5,自引:0,他引:5  
卢广超  许建新  薛立  刘斌  李诗刚  邵怡若 《生态学报》2013,33(24):7872-7881
老鸭嘴,山毛豆,假连翘和葛藤是常见的矿山植被恢复植物。采用盆栽控制土壤水分的方法,测定了这 4 种幼苗叶片的光合和荧光指标,以期为矿山植被的恢复植物筛选提供依据。结果表明(1)干旱胁迫处理期间,4 种幼苗叶片的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)和胞间CO2 浓度(Ci)持续下降,复水8 d后Pn均显著增加,老鸭嘴和山毛豆的GsTr恢复到对照水平,山毛豆和葛藤的Ci恢复到对照水平;假连翘幼苗叶片的气孔限制值(Ls)随干旱胁迫时间的延长而逐渐增加,其他3 种幼苗略降后增加,复水8 d后均恢复到对照水平。(2)干旱胁迫处理期间,4 种幼苗叶片的photosystemⅡ(PSⅡ)光能捕获效率(Fv’/Fm’)、实际光化学量子效率(Yield)和表观电子传递速率(ETR)持续降低,8 d时显著小于对照。复水8 d后,Fv’/Fm’小幅波动,Yield和ETR有所恢复,其中葛藤的Yield和山毛豆的ETR恢复到对照水平;4种幼苗叶片的非化学淬灭(NPQ)持续上升,在第8天显著大于对照,复水8 d后,均持续下降,其中葛藤恢复到对照水平。(3)对光合和荧光指标进行主成分分析表明,干旱胁迫下4 种幼苗的抗旱性能大小顺序为山毛豆 > 老鸭嘴 > 假连翘 > 葛藤。  相似文献   

3.
报道中国茜草科(Rubiaceae)玉叶金花属一新记录种——长瓣玉叶金花(Mussaenda longipetala H. L. Li)。该种在形态上与尾裂玉叶金花(M. caudatiloba D. Fang)和狭瓣玉叶金花(M. lancipetal X. F. Deng & D. X. Zhang)相似,但区别在于叶片长圆状卵形或椭圆状卵形,托叶早落,正常的萼裂片长6~8 mm,花冠管长约3 cm,裂片披针形,长约12 mm。目前仅知分布于越南北部的广宁省和中国的广西北部湾沿海地区。凭证标本存放于广西植物标本馆(IBK)。  相似文献   

4.
Michelia tonkinensis A. Chev.这个名称在发表时未指定模式,曾被处理为M. balansae (Aug. DC.) Dandy的异名。在查阅了其原白和原始材料后,确认采自越南北部Tuyen Quang省的标本——Fleury 37.667 (P)是该种唯一的原始材料,应该作为模式看待,同时确认Michelia tonkinensis是一独立的种,不应该处理为M. balansae的异名。此外,还提供了M. tonkinensis的异名、俗名、描述、分布及查阅的标本等综合信息。  相似文献   

5.
长潭水库是广东梅州市重要的备用水源地,属于国家一类水源保护区。2010年7月,通过分析长潭水库浮游生物群落组成、生物量及多样性指数等群落结构特征和水体理化指标,揭示长潭水库富营养化水平。结果显示,长潭水库鉴定出55种浮游植物,隶属于6个门,优势种为绿藻门的栅藻(Scenedesmus sp.)、蓝藻门的微囊藻(Microcystis sp.)和伪鱼腥藻(Pseudanabaena sp.)、隐藻门的隐藻(Cryptophyta sp.)以及硅藻门的小环藻(Cyclotella sp.)和针杆藻(Synedra sp.);藻类密度范围1.71×106~2.44×108 cells/L;浮游动物共检出44种,包括轮虫、枝角类和桡足类,其中轮虫是主要类群。综合营养状态指数评价结果显示,长潭水库部分水体呈轻度富营养化。典范对应分析结果显示,浮游动物、溶解氧、总氮、总磷和化学需氧量是影响长潭水库浮游植物群落结构的关键环境因子。  相似文献   

6.
首次报道中国爵床科(Acanthaceae)一新记录种:大叶可爱花(Eranthemum macrophyllum Wall.ex Nees)。该种原记载分布于缅甸,在中国仅见于云南省铜壁关省级自然保护区。为名称Eranthemum macrophullus指定了后选模式。  相似文献   

7.
苹果三维树冠的净光合速率分布模拟   总被引:3,自引:0,他引:3  
高照全  赵晨霞  张显川  冯社章 《生态学报》2012,32(21):6688-6694
构建三维树冠光合模型可模拟出叶片净光合速率(Pn)、气孔导度(Gs)和光能利用效率(LUE)在树冠内的三维分布。以17年生纺锤形"富士"苹果树(Malus domestica Borkh. cv. ‘Fuji’)为试材,通过实测确定三维树冠内叶片和辐射分布,根据不同部位叶片最大光合速率经验公式模拟叶片Pn 在三维树冠空间内分布,并据2007-2009年测定数据拟合相关模型参数。模拟表明,苹果树冠叶片Pn 和辐射的三维分布相似,在树冠上部Pn 三维分布比较平缓,然后随辐射的减少而迅速降低。高辐射条件下(PAR=1500 μmol·m-2·s-1),从树冠上部3 m处降到到1 m,平均相对辐射从71.18%降到8.05%,减少了89%,叶片平均Pn从15.05 μmol·m-2·s-1降到1.92 μmol·m-2·s-1,减少了87%。单位体积小室内的总净光合速率大小主要取决于叶面积密度,部分取决于PnGs三维分布与Pn相似,而LUE分布与辐射相反,中下部高,上部低。根据光合机理模型、树冠内辐射和叶面积三维分布可模拟出苹果三维树冠内叶片的PnGs和LUE分布,该模型参数少,可方便用于其它果树三维光合模型构建和果树整形修剪研究。  相似文献   

8.
关于厦门的紫水鸡   总被引:1,自引:1,他引:0  
19世纪中叶,英国鸟类学家Robert Swinhoe曾两次报道紫水鸡(Porphyrio porphyrio)在福建厦门的记录:当他本人第一次看到1只饲养在他人笼舍中的个体时,即判定它肯定不是P.poliocephalus[Latham,1801]而有可能是P.smaragdinus[Temminck,1827][1];两年后,当Swinhoe得到1只活体时,他认为该鸟应当是P.smaragdinus之下的一个亚种,同时,考虑到该鸟在形态上与P.smaragdinus略有差异,Swinhoe又"试探性地"将它命名为Porphyrio coelestis sp.nov.[2]。无论Swinhoe当年的分类意见得当与否,他的这两次记录,都应当是发表于正式学术刊物上论证紫水鸡在中国有见的最初记录。  相似文献   

9.
利用聚合酶链式反应-单链构象多态(PCR-SSCP)技术检测中国美利奴羊(Ovis aries var. Merino)心型脂肪酸结合蛋白基因(H-FABP)外显子2的单核苷酸多态性(SNPs)和遗传多态性,分析其与肌内脂肪(IMF)含量、肌纤维直径和肌纤维密度的相互关系,为该品种绵羊的分子标记辅助选择提供理论依据。结果显示,H-FABP基因外显子2有AA、AB和BB 3种基因型,AA型和BB型在778位均发生了C缺失,939位均发生了A→G转换,BB型还在789位发生了T→C转换,该突变导致所编码氨基酸发生了缬氨酸→丙氨酸的替换;BB型为IMF的优势基因型,与AB型相比差异显著(P<0.05),与AA型相比差异极显著(P<0.01);BB型对肌纤维直径存在负相关。结果提示,中国美利奴羊H-FABP基因外显子2具有多态性,该基因可能是中国美利奴羊肉质性状的主效基因,或者与控制肉质性状的主效基因相连锁。  相似文献   

10.
为了确定γ-氨基丁酸B受体(gamma-aminobutyric acid B receptor,GABABR)基因在异育银鲫(Carassius auratus gibelio)不同组织中的表达,本实验分别对异育银鲫不同组织中GABABR1基因进行RT-PCR扩增,并进行了克隆和测序,在与GenBank基因库中已知GABABR1序列进行同源性比对的基础上采用邻接法构建系统发育树,并进一步分析其在异育银鲫不同组织内的表达水平。经克隆获得异育银鲫GABABR1基因CDS区序列383 bp,编码127个氨基酸。荧光定量PCR结果显示,GABABR1基因在异育银鲫脑、肝、肾、心、肠、鳔、鳃、肌、尾鳍、脾、卵巢、精巢组织中均有表达,且在不同组织中的表达水平由高到低依次是:脑>尾鳍>精巢>心、肠、鳔>卵巢、脾、鳃、肌>肝、肾。本研究证实了GABABR1基因在异育银鲫各组织中表达的广泛性,且有明显的组织特异性。  相似文献   

11.
We present a network of thirteen annual ring-width chronologies from high elevation whitebark pine (Pinus albicaulis Engelm.) sites in the western Canadian Cordillera in order to assess the dendroclimatic potential of this long-lived tree species. The temperature signal within the chronologies is complex and strongly influenced by diverging trends in the summer temperature and ring-width records from across the region. A first differences transformation of the tree-ring and temperature records illustrates a loss of frequency coherence in growth response to summer temperatures following reduced radial growth in the 1950s. Prior to reduced growth, we note a positive association with summer temperatures for both first differenced (rd = 0.60) and traditional (r = 0.50) records. Following reduced growth, the association at first differences is maintained (rd = 0.49) whereas there is a change in the lower frequency component of tree growth response to summer temperatures (r = ?0.34). We suggest the cause of this reduced temperature sensitivity is related to the interaction between diurnal temperature and cloud cover patterns, the hydrological regime of snowpack, and site conditions which have been amenable to the initiation of moisture stress during the latter half of the 20th century. Reduced radial growth is coincident with the arrival of white pine blister rust (Cronatium ribicola J.C. Fisch. ex Raben) into the study region which suggests this infestation may be related to the observed reduction in radial growth. Whitebark pine has considerable potential for the field of dendroclimatology. Unfortunately, the decline of the species due to the combined effects of climate change, white pine blister rust, mountain pine beetle (Dendroctonus ponderosae Hopk.), and forest fire exclusion practices indicate this potential may remain unfulfilled.  相似文献   

12.
彭剑峰  杨爱荣  田沁花 《生态学报》2011,31(20):5977-5983
以万仙山油松(Pinus tabulaeformis)为样本,建立了油松树木年轮宽度序列的标准年表(STD)。与附近气象因子的相关结果表明:与当年6月平均温度呈较为显著的负相关,与前一年的9月和当年的5月以及春季(3-5月)的降水量呈显著正相关,显然影响万仙山油松生长的主要气候因子是5月(或说春季)降水和6月温度。树轮指数与各月PDSI相关值都很高(其中与当年5月的PDSI相关值高达0.614),都超过95%的置信水平,说明水热组合是该区域油松生长的主要限制因子。研究表明,影响本区油松生长的气候因子与我国北方地区油松生长的影响因子有较高的一致性,尤其是生长季前期的温度影响都很大;而其降水的影响及其与PDSI的相关都明显超前于黄土高原及北方地区,这既说明影响油松生长的大气候因子相似,又表明夏季风从东南向西北的不断推进。  相似文献   

13.
The pinewood nematode, Bursaphelenchus xylophilus, was inoculated into established native jack and red pines (Pinus banksiana and P. resinosa) and exotic Austrian pine (P. nigra) in Minnesota and Wisconsin forests during summer 1981. The nematode isolates did not kill established nonstressed pine trees growing in the forest. However, the same nematode isolates killed pine seedlings under greenhouse conditions. Girdling the main stem of some trees to induce stress resulted in the death of the majority of inoculated and noninoculated branches of Austrian and jack pines, but no branch death was observed on red pine. Greater numbers of nematodes were extracted from branches of inoculated, girdled trees than from nongirdled trees. The mean number of nematodes extracted from branches of inoculated, nongirdled trees was 0.3 - 14 nematodes per gram of wood.  相似文献   

14.
The transmission of Bursaphelenchus xylophilus from Monochamus alternatus males to Pinus densiflora trees via oviposition wounds has been determined. Nematode-infested males, with mandibles fixed experimentally to prevent feeding, were placed for 48 hours with pine bolts containing oviposition wounds that had been made by nematode-free females. After removal of the nematode-infested males, the pine bolts were held for 1 month and then examined for the presence of nematodes. Reproducing nematode populations were recovered from pine bolts that were exposed to male beetles carrying a high number of nematodes. No reproducing nematode population could be recovered from pine bolts exposed to beetles with a small number of nematodes. Nematode reproduction in the pine bolts was not related to the number of oviposition wounds per bolt. Fourth-stage dispersal B. xylophilus juveniles, collected from beetle body surfaces, were inoculated on pine bolt bark 0, 5, 10, and 15 cm away from a single artificial, small hole. These dauer juveniles successfully entered some bolts. The probability of successful nematode reproduction decreased with increased distance between inoculation point and artificial hole. The results indicated that B. xylophilus can move a significant distance to oviposition wounds along the bark surface and enter a tree via the wounds. The new transmission pathway is considered important for the nematode to persist in pine forests such as in North America where pine wilt disease does not occur.  相似文献   

15.
马泽清 《生态学报》2011,31(6):1525-1537
基于树干解析和树轮分析,结合野外调查,揭示了我国主要外来树种--湿地松(Pinus elliottii)的生长规律,从而为人工林经营管理和生态系统服务功能评估提供了依据。2005年调查了1948年江西吉安青原山引种后存留的564株湿地松(1954 1958年生)。胸径(DBH, diameter at breast height)平均值为34.2 cm(18.4-58cm),树高平均值为19.5 m(9-33m)。青原山湿地松树轮分析结果显示:52年间,年树轮宽度增长量平均值为0.32 cm,最大年增长量不超过1.14 cm。胸径年生长量总体上呈下降趋势,直径生长高峰出现在10a左右;林龄达到20a左右时,直径年生长量开始下降;林龄40a后,生长变得极为缓慢。距青原山西南100km的千烟洲湿地松林(20年生)胸径和树高平均值分别为15.9 cm和11.0 m;20a的胸径生长量平均值为0.86 cm;材积方程为V= 0.0000213 D2.9870924(V为带皮材积,D为胸径)。千烟洲湿地松林生物量低于同期营造的马尾松(Pinus massoniana)林生物量,也明显低于中亚热带地带性植被樟树(Cinnamomum camphora)林的生物量。经比较发现,引种营造的湿地松林,其生长量远不如原产地美国佛罗里达州湿地松林。  相似文献   

16.
Using low‐coverage whole‐genome sequencing, analysis of vocalizations, and inferences from natural history, we document a first‐generation hybrid between a rose‐breasted grosbeak (Pheucticus ludovicianus) and a scarlet tanager (Piranga olivacea). These two species occur sympatrically throughout much of eastern North America, although were not previously known to interbreed. Following the field identification of a putative hybrid, we use genetic and bioacoustic data to show that a rose‐breasted grosbeak was the maternal parent and a scarlet tanager was the paternal parent of the hybrid, whose song was similar to the latter species. These two species diverged >10 million years ago, and thus it is surprising to find a hybrid formed under natural conditions in the wild. Notably, the hybrid has an exceptionally heterozygous genome, with a conservative estimate of a heterozygous base every 100 bp. The observation that this hybrid of such highly divergent parental taxa has survived until adulthood serves as another example of the capacity for hybrid birds to survive with an exceptionally divergent genomic composition.  相似文献   

17.
Michael Staab 《ZooKeys》2014,(391):65-73
A new species of army ant from the Aenictus wroughtonii group is described and illustrated based on the worker caste. Aenictus gutianshanensis Staab, sp. n. is known form a single colony collected in the subtropical mixed evergreen broad-leaved forest of the Gutianshan National Nature Reserve, South-East China. The new species is probably most closely related to A. vieti Jaitrong & Yamane, 2010 known from North Vietnam and Taiwan. It is suggested that the abundant records of A. camposi Wheeler & Chapman, 1925 from East and South-East China should be reevaluated, as they are probably A. gutianshanensis or A. vieti and not A. camposi, which is distributed in Sundaland, the Philippines, and the southernmost part of continental South-East Asia.  相似文献   

18.
Based on the examination of newly collected material and additional specimens housed in Chinese collections, our knowledge of Gastroserica Brenske, 1897, is expanded. Here, seven new species are described, including habitus photographs and illustrations of the male genitalia: Gastroserica haoyui sp. n. (China: Zhejiang Prov.), G. fengduana sp. n. (China: Sichuan Prov.), G. wenzhui sp. n. (China: Guangxi Prov.), G. damingshanica sp. n. (from China: Guangxi Prov.), G. jinxiuensis sp. n. (China: Guangxi Prov.), G. liboensis sp. n. (China: Yunnan Prov.) and G. carolusi sp. n. (Laos). Additionally, we provide a distribution map of the new taxa and new distribution records of the known taxa.  相似文献   

19.
Bursaphelenchus xylophilus, pinewood nematode (PWN), is the most serious pest of pine forests in Japan, but in North America its role in pine wilt disease is still being studied. The PWN is known to infest many species of Pinus, with P. nigra, P. sylvestris, and P. thunbergii the most susceptible in the eastern United States. Because of its potential, several European countries (Finland, Norway, and Sweden) and Korea have established embargoes against the importation of coniferous wood from regions of the world known to be infested with the PWN. Although the PWN is not considered an economic pest in North American forests, the recent embargoes have established an impact on current forest management practices and an economic impact on North American export trade.  相似文献   

20.
自Swinhoe的早期记录跨越140余年后,2012年3月紫水鸡(Porphyrio porphyrio)终于在厦门被重新发现并得以确认其繁殖群的存在.继而在检视以往文献过程中,注意到对于紫水鸡在中国状况的认识,无论是对其分布,还是亚种认定,均多存疑问之处.本文对紫水鸡在中国南方各省(区)的发现和记录过程做了大致梳理,概述了以往对中国东南沿海地区紫水鸡分布认识误区的产生原因,并指出当今中国鸟类学界对中国紫水鸡亚种分布态势上的不同意见.作者提出这些问题与同行探讨,以期促成消弭疑问,并希望鸟学界同仁能够关注紫水鸡在中国的动态变化与发展.  相似文献   

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