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1.
天牛科纤维素酶同工酶研究 总被引：8，自引：1，他引：8
用聚丙烯酰胺凝胶等电聚焦电泳方法分析了天牛科两个亚科１８种雌成虫、１２种幼虫消化道中肠组织纤维素酶复合酶中Ｃｘ酶同工酶．Ｃｘ酶同工酶在亚科间、族间差异较大；同族内各属间的酶谱差异也较大；同属内不同种间酶谱较接近，但每种各具其特征酶带，彼此易区分。Ｃｘ酶同工酶用于亲缘关系相近种的分类、鉴定有重要价值，可作为天牛科分子分类的一个有用的辅助手段。文章还就楔天牛族Ｓａｐｅｒｄｉｎｉ的分类系统问题进行了讨沦． 相似文献
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Several native poplar species meet at the margins of their natural distributions in southern Alberta, Canada. In this semi-arid area, poplars are obligate riparian species but they occupy several intergrading ecoregions. Populus deltoides Bartr. ex Marsh predominates in the warmest and driest eastern prairie ecoregions; P. balsamifera L. occupies the cooler and wetter western parkland and montane ecoregions; and P. angustifolia James and hybrids between the species occur in the intermediate grassland ecoregions. We investigated stomatal characteristics of these poplars in 51 genotypes collected across the range of ecoregions and grown in a semi-arid common garden. Stomatal length differed among genotypes within species but did not differ among species, ranging from 19 to 22 microm. Total stomatal densities (adaxial plus abaxial) differed among genotypes within species but were similar among species (290-420 stomata mm(-2)). Single-surface stomatal densities differed among species and consequently, the ratio of adaxial:abaxial stomatal density also differed, ranging from 0.94 for P. deltoides to 0.27 for P. balsamifera, with intermediate stomatal density ratios in P. angustifolia and hybrids. In a subsequent study of a subset of the same genotypes, stomatal density was correlated with stomatal conductance (r2 = 0.75) and the conductance ratios differed among species in the same manner as the stomatal density ratios. We conclude that: (1) diverse poplar genotypes respond similarly to a semi-arid environment by producing comparatively small and dense stomata; (2) differences in stomatal density underlie differences in stomatal conductance and differences among species in stomatal density ratio or conductance ratio may reflect adaptation to climatic differences among ecoregions; and (3) there is substantial variation in stomatal characteristics within and among species and hybrids in this area that could be useful for the selection and breeding of poplars adapted to different climatic conditions. 相似文献
3.
2016~2017年,对贵州省德江县楠杆省级自然保护区范围内的兽类资源进行了调查,基本掌握了保护区内兽类资源状况。调查共记录兽类41种,隶属8目19科。区系上,以东洋界物种和广布种居多,其中,古北界物种5种(12.20%)、广布物种17种(41.46%)、东洋界物种19种(46.34%);分布型上,东洋型物种较多,共23种(56.10%),古北型8种(19.51%),南中国型7种(17.07%),全北型、季风型和不易归类型物种均为1种(2.44%);生态型方面,以地面生活型最多(18种),其次为半地下生活型(11种);国家I、II级重点保护动物10种,占保护区兽类总数的24.39%;中国脊椎动物红色名录中极危物种2种,濒危物种3种,近危物种8种,易危物种7种。贵州楠杆保护区与梵净山保护区(Jaccard相似性系数为0.42)和宽阔水保护区(Jaccard相似性系数为0.46)兽类物种均表现为中等不相似;与麻阳河保护区的兽类群落相似性则表现出中等相似的现象(C=0.53)。楠杆自然保护区内兽类物种主要体现东洋界亚热带物种为主的区系特征,保护物种较丰富,但受人为干扰较严重,管理机构应加强保护区内野生动物保护工作,并完善相应的管理法规,为保护区内生物资源保护打下坚实基础。 相似文献
4.
通过对湖南书院洲国家湿地公园两个不同断面鱼类进行了连续监测,对其群落组成、生物多样性、优势种组成进行了比较分析。调查发现:有鱼类30种,隶属于5目9科。两个不同生境断面的鱼类小型鱼类均以鲤形目鲤科鱼类为主,且多为小型鱼类。在鱼类的群落结构多样性度量值差异不大:(1)断面Ⅰ鱼类分5目7科22种;断面Ⅱ有鱼类分4目7科19种;(2)断面Ⅰ和断面Ⅱ的多样性指数分别是2.58和2.67,均衡度指数是0.835和1.1,种类相似性指数是53.7%。本次调查还发现湿地公园鲤形目鲤科鱼类新记录5种:分别是银鮈、似鮈、达式鲌、飘鱼和红唇薄鳅。 相似文献
5.
北京山区植物多样性保护区域规划研究 总被引：4，自引：0，他引：4
对北京地区东灵山、松山、雾灵山等13个保护区的植物物种的丰富度,植被类型多样性进行调查,其中松山保护区的物种数最多,有787种;喇叭沟门保护区群系类型最多,有26个。不同保护区之间的物种相似系数很高,大部分在0．6以上,群系类型的相似系数较低,大部分在0．5以下,说明不同保护区之间的群系类型存在一些差异,聚类分析结果基本与相似性系数分析的结果一致。根据相似性分析和聚类结果把北京地区划分为4个物种、植被类型相对较为一致的植物多样性保护区域。 相似文献
6.
The mountain pine beetle (MPB), the most serious pest of lodgepole pine in mountainous western Canada, spread northeastward into lodgepole × jack pine hybrids in the boreal forest of Alberta in 2006. The MPB vectors three species of blue‐stain fungi, which contribute to the success of the beetles. These fungi were isolated from MPB larvae and galleries in several lodgepole × jack pine stands in the Grande Prairie region of northwestern Alberta in autumn 2006 and winter and spring 2007. Fungi were recovered from more than 95% of gallery systems. The three fungi were similarly prevalent but Ophiostoma montium was the most frequently isolated fungus at each sampling point, isolated from 72% to 90% of gallery systems compared with 63% to 78% for Grosmannia clavigera, and 61% to 86% for Leptographium longiclavatum. Ophiostoma montium and G. clavigera were isolated from more larvae than gallery samples, with the opposite true for L. longiclavatum. Most gallery systems contained multiple fungi with three fungi per gallery system being more common in autumn and winter and two fungi more common in the spring. The combination of G. clavigera and L. longiclavatum was less common among gallery systems with two fungi than either of the pairwise combinations containing O. montium. Fungal prevalence was the same above and below snow level. The prevalence of the three fungi did not differ significantly among stands sampled in the spring but stands with more G. clavigera tended to have less L. longiclavatum. The winter of 2006–2007 was colder than average throughout Alberta with temperatures below ?30°C in November, January and February, and all three fungi were present after the cold winter while most larvae had died, suggesting that overwintering mortality of the fungi will not limit persistence and spread of MPB in the boreal forest. 相似文献
7.
M. Kauhanen E. J. Vainio J. Hantula G. G. Eyjolfsdottir P. Niemelä 《Forest Pathology》2006,36(6):434-446
Endophytic fungi were isolated from surface‐sterilized needles of the Siberian larch. Samples were collected from a native growing site of the Siberian larch in north‐western Russia and from sites in Russia, Finland and Iceland where the Siberian larch has been introduced. The isolated fungi were classified to operational taxonomic units (OTUs) using colony morphology and molecular characteristics. Needle colonization rates were 50–99% and in total 79 OTUs were found. There were five common OTUs, which covered 86.2% of all isolates. The most common OTU lacked from the youngest plantations in Finland (Solböle) and in Iceland (Kjarnaskógur). The highest similarity in regard to the frequency of OTUs occurred among the stands established long ago in Finland, and the UPGMA clustering using similarity indices separated the seven stands into two major groups. 相似文献
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9.
C. R. Y. Munthali P. W. Chirwa W. J. Changadeya F. K. Akinnifesi 《Agroforestry Systems》2013,87(1):117-130
Baobab (Adansonia digitata L) belonging to Bombacaceae family, is one of the most widely used indigenous priority tree species in sub-Saharan Africa, valued in the cosmetic industry for its seed oil, and powdery fruit pulp for juice making. Baobab has high potential for domestication in southern Africa, therefore understanding its genetic diversity and population structuring is warranted. The study investigated the level of genetic diversity and differentiation of five populations of A. digitata L. sampled from four diverse silvicultural zones in Malawi. Variation at nine microsatellite loci were examined in 150 individual trees. Low mean genetic diversity was expressed through genetic diversity indices: Nei’s genetic diversity (h, 0.18 ± 0.03), Shannon Information Index (I, 0.21 ± 0.07), observed number of alleles (na, 1.47 ± 0.10), effective number of alleles (ne, 1.23 ± 0.04) and percentage polymorphic loci (pp, 48 %). The low genetic variation found is attributed to the population growing in marginal areas of genetic centre of diversity of the species, anthropogenic factors and founder effects. Moderate genetic differentiation was observed among populations (Gst = 0.13) indicating the presence of a large number of common alleles resulting in a homogenisation effect. Clustering of individual trees by genetic similarity coefficients indicated that mainland trees were genetically closer than the trees on Likoma Island. Mantel’s test showed a weak positive insignificant correlation (Z = 0.12; P = 0.64) between genetic distance among populations and actual distance on the ground implying that geneflow was not directly influenced by isolation by distance. The results suggest that seed distribution and tree improvement should recognise the presence of ecotypes and conservation measures should protect all the populations due to existence of private alleles which are of adaptive importance. 相似文献
10.
Photosynthetic light and temperature response curves were measured seasonally in seedlings of white spruce (Picea glauca (Moench.) Voss) grown for two years in the understory of aspen (Populus tremuloides Michx.) or in the open in central Alberta. Light-saturated rate of net photosynthesis, the optimum temperature for net photosynthesis, transpiration rate, photochemical efficiency, and stomatal and mesophyll conductances increased from spring to summer and declined thereafter, whereas dark respiration rate and compensation and saturation points were highest in spring. Depression of photosynthetic parameters was greater in open-grown seedlings than in understory seedlings during the periods in spring and autumn when night frosts were common. Net photosynthetic rates were similar in understory and open-grown seedlings in summer, but they were significantly lower in open-grown seedlings in spring and autumn. Significantly lower transpiration rates and stomatal conductances in open-grown seedlings than in understory seedlings were also observed at 15 and 25 degrees C in the autumn. Shoot and needle growth were less in open-grown seedlings than in understory seedlings. In summer, when irradiances were low in the aspen understory, understory white spruce seedlings maintained a positive carbon balance by decreasing their compensation and saturation points and increasing their photochemical efficiency compared to spring and autumn. 相似文献
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12.
雷公山自然保护区交密辖区鸟类多样性 总被引：1，自引：0，他引：1
2007年7月至2008年6月,采用路线法对雷公山国家级自然保护区交密管理站辖区内的鸟种类进行调查,共记录鸟类76种,分别隶属于10目30科。从居留类型来看：留鸟55种,夏候鸟15种,冬候鸟4种及旅鸟3种;从区系从属来看：东洋种44种,古北种8种,广布种24种。此次调查共记录保护区新纪录8种,受《濒危野生动植物种国际贸易公约》保护的鸟类2种,国家Ⅱ级重点保护的鸟类7种。并对自然保护区的鸟类资源保护提出了几点建议。 相似文献
13.
用支序分析方法讨论了7种紫胶虫之间的系统发育关系,选择肛突长度、膊背高度等22个形态性状,进行支序分析,得出7种紫胶虫系统发育关系图.结果显示:中华紫胶虫的形态较为特殊,与其它6种差异较大,最先从群体中分化出来,是最原始的种类;其它6种紫胶虫稳定地分化为两大支系:信德紫胶虫与紫胶蚧构成一个支系,二者在外部形态结构上有许多相似的地方,形成紧密的姐妹群关系,主要分布在印度次大陆热带地区,属于较原始的种类;在另一支系中,尼泊尔紫胶虫首先分化出来,也属于比较原始的种类;普萨紫胶虫紧随其后分化出来;田紫胶虫与云南紫胶虫最后分化出来,是最进化的物种,同时它们在形态结构上相似,形成姐妹群关系,这4种紫胶虫主要分布在欧亚板块的热带、亚热带地区.紫胶虫的外部形态与其地理分布及生境有着密切的关系. 相似文献
14.
Herbivores, such as beavers (Castor canadensis) and ungulates, can dramatically alter the species composition and structure of riparian vegetation communities. We examined how four different levels of beaver presence and ungulate density influenced the structure and composition of riparian vegetation communities in the mixed-wood boreal region of east-central Alberta, Canada. Beavers, as central-place foragers, focus on similar species utilized by the six ungulate species in our study area. However, we found that vegetation responded differently relative to the percent cover and heights of emergent, shrub, herbaceous dicots, and tree species depending on the varying combinations of beaver presence and ungulate densities. There was an obvious negative effect of ungulate herbivory on shrub heights and cover; however, we were unable to find any significant effects on the overall composition and structure of vegetation communities that were exclusively related to beaver activities. In areas with no beavers and lower ungulate densities there was a positive growth response in preferred species (e.g., Salix spp., Prunus spp.), which clearly demonstrated the degree of combined influence that these herbivores have on riparian communities. In these areas, Salix spp. was four times shorter than in areas where beavers were not present and ungulate densities were lower. In addition percent cover was lowest for emergent vegetation and herbaceous dicots in areas with higher ungulate densities. Many studies focus on single-species effects on forage resources, yet our research shows that the study of combined effects of multiple herbivores can provide a new insight into these complex systems. 相似文献
15.
蒙格罕山自然保护区野生脊椎动物资源调查结果表明：保护区内野生脊椎动物有4大类17目37科103种,其中：以鸟类种数最多,有11目24科76种,占保护区脊椎动物总数的73.8%;其次是哺乳类,有4目9科17种,占16.5%;两栖类有1目2科4种,占3.9%;爬行类有1目2科6种,占5.8%。 相似文献
16.
江西庐山自然保护区爬行动物多样性调查与分析 总被引：2，自引：0，他引：2
为促进自然保护区的管理,加强生物多样性的保护,申报国家级自然保护区,于2005年8月中旬、2006年5月下旬~6月上旬、2006年7月下旬,前后3次对江西庐山自然保护区爬行动物资源进行了实地调查.结果表明:江西庐山自然保护区现已记录的爬行动物有42种,隶属3目9科,占江西省已记录80种爬行动物的52.50%,比庐山爬行动物原记录新增10种,其中32种属东洋界种类,10种属广布种、无古北界种类,42种爬行动物均属"国家保护的有益的或者有经济、科学研究价值的陆生野生动物".最后同江西省其它6个自然保护区的爬行动物进行了物种相似性系数比较和聚类分析,并提出了5条保护建议. 相似文献
17.
四川海子山自然保护区鸟类群落结构及多样性 总被引：5，自引：0，他引：5
应用样线法,调查海子山自然保护区鸟类的组成和群落结构,经调查确认保护区内有鸟类16目48科210种,以留鸟和夏候鸟为主,鸟类区系成分复杂,古北界种类略占优势。根据鸟类栖息地的生境类型,将保护区鸟类划分为5个群落。调查得知,不同群落的优势种、常见种有较大差异;同一群落类型的物种组成、数量、遇见频次的季节差异明显。运用Shannon Weinner指数计算各群落的多样性;采用E=H／Hmax。计算群落中各群落物种的均匀度;用百分率相似性数（index of percent similarity）对各群落做相似性比较。结果表明：保护区内鸟类群落结构与各群落类型内部的空间异质性程度密切相关,群落的空间结构越复杂,则物种多样性就越高;湿地鸟类群落的均匀度指数最高,而高山灌丛鸟类群落的均匀度指数最低;各群落类型百分比相似性指数均较低;鸟类群落结构具有较大差异。 相似文献
18.
The semiterrestrial grapsid crab Chasmagnathus granulata Dana is one of the most predominant inhabitants of brackish salt marsh ecosystems in South America. Its early postembryonic stages were reared in the laboratory from hatching of the first larval stage through the first juvenile crab instar, and changes in the quantity and elemental composition of biomass (measured as dry weight, W; carbon, C; nitrogen, N; hydrogen, H) were investigated in short intervals of time (every 1 or 2 d). In a series of successive developmental stages, the accumulation of biomass per individual can be described as an exponential function of the number of moults. In contrast, the pattern of growth within individual moulting cycles is described with best fit of observed and predicted data as a quadratic function of development time elapsed since last ecdysis. Weight-specific instantaneous growth rates show decreasing trends within the moulting cycle. Cumulative biomass increments during larval development of C. granulata are among the highest on record for brachyuran crabs. The quantities and patterns of larval growth are in this species similar as in most marine brachyuran crabs, for which data are available, but different from those in some other semiterrestrial grapsid crab species, which live in similar brackish water habitats as C. granulata. Hence, the early postembryonic stages of C. granulata do not show special bioenergetic adaptations to the non-marine conditions, which prevail in the adult habitat of this species. This reflects a strategy of larval export to the sea, i.e. a reproductive dependence of this species on the marine environment. 相似文献
19.
We compared vertical gradients in leaf gas exchange, CO(2) concentrations, and refixation of respired CO(2) in stands of Populus tremuloides Michx., Pinus banksiana Lamb. and Picea mariana (Mill.) B.S.P. at the northern and southern boundaries of the central Canadian boreal forest. Midsummer gas exchange rates in Populus tremuloides were over twice those of the two conifer species, and Pinus banksiana rates were greater than Picea mariana rates. Gas exchange differences among the species were attributed to variation in leaf nitrogen concentration. Despite these differences, ratios of intercellular CO(2) to ambient CO(2) (c(i)/c(a)) were similar among species, indicating a common balance between photosynthesis and stomatal conductance in boreal trees. At night, CO(2) concentrations were high and vertically stratified within the canopy, with maximum concentrations near the soil surface. Daytime CO(2) gradients were reduced and concentrations throughout the canopy were similar to the CO(2) concentration in the well-mixed atmosphere above the canopy space. Photosynthesis had a diurnal pattern opposite to the CO(2) profile, with the highest rates of photosynthesis occurring when CO(2) concentrations and gradients were lowest. After accounting for this diurnal interaction, we determined that photosynthesizing leaves in the understory experienced greater daily CO(2) concentrations than leaves at the top of the canopy. These elevated CO(2) concentrations were the result of plant and soil respiration. We estimated that understory leaves in the Picea mariana and Pinus banksiana stands gained approximately 5 to 6% of their carbon from respired CO(2). 相似文献
20.
《林业研究》2016,(5)
The genus Armeniaca Scop.is well known for its popular cultivated edible fruit trees such as Armeniaca vulgaris Lam.and ornamental flowers such as A.mume Sieb.Another species,A.cathayana Fu et al.,one of six important dry fruits(kernel-using apricot),is cultivated for its edible seeds in North China.In the present study,DNA from 70 individuals of Armeniaca,including 38 of A.cathayana,18 of A.vulgaris,12 of A.sibirica,1 of A.dasycarpa and 1 of A.mume,was extracted and analyzed using microsatellites and capillary electrophoresis.For 20 polymorphic loci selected,339 alleles and 140.7 effective alleles were detected.The number of alleles per locus ranged from 8 to 28,with an average of 16.95 alleles per locus.The observed heterozygosity(Ho) and the expected heterozygosity(He) ranged from 0.427 to 0.971 and from 0.737 to 0.912,respectively.The polymorphism information content varied from 0.708 to0.905,with an average of 0.827.Based on the genetic similarity among 70 individuals,a UPGMA was used to establish the phylogenetic relationships.The taxonomic positions among five species were clearly revealed,and A.cathayana was more closely related to A.vulgaris than to A.sibirica.The results will provide a scientific basis for research on the taxonomy,germplasm resources and breeding of Armeniaca,especially for A.cathayana. 相似文献