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1.
The Phytophagous Insects Data Base (PIDB) was used to summarize information about 6933 species of British insects/mites and their food-plant families. Total species in 183 insect families on 127 vascular plant families were correlated with numbers of plant species in each family in Britain and Europe, accounting for 41.8% of the variation. Families with trees had more insects, while ferns and aquatic, uncommon and ephemeral plants, particularly orchids, had fewer. Seven individual insect families were analysed separately: Aphididae were more closely correlated with plant species numbers than were the more polyphagous Geometridae. Agromyzidae were uncommon on families with trees. Of insect species 75.8% fed on only one plant family and 10.1% were recorded on two families. Species feeding on three families or more were considered to be polyphagous. In the 30 largest insect families, eight had species feeding on only one plant family, while 12 had more than 20% of their species polyphagous. Proportions of family-restricted insects were high on Pinaceae, Gramineae and Compositae, but low on Corylaceae, Primulaceae and Tiliaceae. More pest species were polyphagous. Polyphagy was related to large larvae, larvae overwintering, wood-feeding, ephemeral food sources, poor dispersal abilities and omnivory. Some polyphagous species might be actively evolving in exploitation of vacant niches, leading to later progressive specialization to food-plants.  相似文献   

2.
The anthocyanin content of 23 grass species (Poaceae) belonging to five subfamilies has been determined. Altogether 11 anthocyanins were identified; the 3-(6″-malonylglucosides) and 3-glucosides of cyanidin, peonidin and delphinidin, the 3-(3″,6″-dimalonylglucoside), 3-(6″-rhamnosylglucoside) and 3-(6″-glucosylglucoside) of cyanidin, in addition to peonidin 3-(dimalonylglucoside) and delphinidin 3-(6″-rhamnosylglucoside). Anthocyanins acylated with one and/or two malonic acid moieties dominated the anthocyanin profiles of all the species in the subfamilies Pooideae and Panicoideae. On the other hand, the 3-glucoside and 3-rutinoside of cyanidin were the major anthocyanins in Sinarundinaria murielae (subfamily Bambusoideae) and Molinia caerulea (subfamily Arundinoideae), while the 3-glucosides of cyanidin and peonidin were the principal anthocyanins in rice, Oryza sativum (subfamily Oryzoideae). Pelargonidin derivatives and free anthocyanidins have previously been reported to occur in several Poaceae species, however, not identified in any of the species included in this survey.  相似文献   

3.
河南省猛禽的调查   总被引:5,自引:1,他引:4  
主要论述河南省猛禽的种类、数量、分布及迁徙规律,河南省的猛禽共计41种,其中隼形目鸟类2科29种,Hao形目鸟类2科12种。  相似文献   

4.
重庆市主城区苔藓植物区系研究   总被引:1,自引:0,他引:1       下载免费PDF全文
对采集的1500份标本进行鉴定并查阅相关文献,共统计出重庆市主城区苔藓植物34科65属206种(含苔类13科14属25种,藓类21科51属181种,重庆市新记录80种),并整理了重庆市主城区苔藓植物名录。其中优势科有丛藓科、青藓科、真藓科、灰藓科、绢藓科和羽藓科,占总种数的62.14%;优势属有青藓属Brachythecium、真藓属Bryum、绢藓属Entodon、美喙藓属Eurhynchium、毛口藓属Trichostomum、凤尾藓属Fissidens、湿地藓属Hyophila和灰藓属Hypnum,占总种数的41.26%。区系成分以北温带和东亚成分为主,分别占32.75%和30.41%;其次是热带成分和中国特有成分。通过与临近4个地区的苔藓植物区系比较发现,重庆市主城区与同纬度的杭州市区苔藓植物区系属、种相似性系数最高;而与其地理距离较近的3个区县的属、种相似性系数较低,这主要是由于重庆市主城区与杭州市区处于同纬度,且均以城市人工生境为主。本研究丰富了重庆市苔藓植物资料,为重庆市苔藓植物区系研究奠定了基础。  相似文献   

5.
The conservation of biodiversity is an important goal of most forest management efforts, and proper monitoring of biodiversity requires immediate attention. Coleoptera, the largest order of organisms on Earth, should be monitored as a crucial part of overall biodiversity. To facilitate monitoring of Coleopteran diversity, indicators at the family level that adequately represent the beetle diversity were investigated. One Malaise trap was placed in each of 52 forest stands in the central mountainous region of Japan; all captured beetles were identified to species. Pearson’s correlation coefficients were calculated between the number of species in each family and the total number of species in all families combined. The relationship between the species composition of each family and the overall composition of all families was examined using Mantel tests. Families with high correlation coefficients for species richness included Cerambycidae, Cleridae, Curculionidae, Lycidae, Elateridae. Families exhibiting strong similarity in composition to the composition of all families were Scolytidae, Elateridae, Curculionidae, Cerambycidae, and Staphylinidae and the Cerambycidae, Curculionidae, and Elateridae were determined to be useful surrogates for Coleopteran diversity. All significant pairwise correlations between each of these three families and other Coleopteran families were positive, indicating that each was appropriate as a competent surrogate. Thus, this study identified adequate diversity indicators in Coleoptera that can be caught by Malaise traps. The accumulation of data on indicators obtained through different methods or in different climates is necessary to ensure the selection of widely applicable indicator families as stable surrogates of beetle diversity.  相似文献   

6.
刘艳  皮春燕  田尚 《生物多样性》2016,24(2):244-662
大巴山国家级自然保护区是我国35个生物多样性优先保护区域之一, 但苔藓植物的相关研究仍是空白。本文在详细的野外调查基础上, 记录该保护区苔藓植物57科141属390种, 其中苔类21科31属82种, 藓类36科110属308种, 新增重庆市苔藓植物新记录80种。物种多样性最丰富的科(种数≥ 10种)分别是青藓科、丛藓科、灰藓科、真藓科、提灯藓科和曲尾藓科, 共占总种数的41.03%。物种多样性最丰富的属(种数≥ 10种)分别是青藓属(Brachythecium)、真藓属(Bryum)、绢藓属(Entodon)、光萼苔属(Porella)和耳叶苔属(Frullania), 共占总种数的15.64%。在海拔1,000-2,480 m之间, 苔藓植物的物种多样性呈现随海拔升高先增加后减少的趋势, 其中, 在海拔1,200-1,600 m段物种最为丰富, 建议将这一地带进行优先保护。  相似文献   

7.
山西庞泉沟国家自然保护区种子植物区系研究   总被引:11,自引:1,他引:10  
庞泉沟自然保护区共有种子植物89科359属809种,其中裸子植物2科6属7种,被子植物87科353属802种。含5属以上的科15科,单、寡种属共330属,这些科、属在植物区系组成中具有重要作用。种子植物科、属、种的区系地理成分复杂多样。科的分布区类型中,世界分布型40科,北温带分布型24科,分别占总科数的44.94%和26.97%。属的分布区类型中,温带成分256属,占总属数的82.05%,反映出该区植物区系的温带性质。种的分布区类型中,中国特有分布种居首位,尤以华北成分占优势,其中华北落叶松、黄刺玫、油松等为该区植被建群种或优势种。科、属、种的特有现象不平衡,没有中国特有科,中国特有属、特有种分别为7属、325种。  相似文献   

8.
Aim A comparison of biodiversity patterns within Malesia in relation to surface area. Location Analysis of the patterns in species richness and endemism of vascular plants in the five major Malesian islands, i.e. Java, Sulawesi, Sumatra, Borneo and New Guinea. Methods Available data on species richness and species ranges in correlation with the surface area of the respective islands were examined in this work. Estimations of total species numbers for these islands are presented based on extrapolation of all available published Flora Malesiana information and recent checklists, all in all comprising 12,000 different species. The regression analysis of overall species richness and endemism were studied for all species together as well as for different plant families to compare the fit with the Arrhenius species–area model. Results The five islands form a series of independent areas of increasing size suited for an analysis of the species–area relationships at the regional scale. All species taken together and those of families with even distribution throughout Malesia show significant species–area relationships. Non‐significant relationships were detected in families with western or eastern‐centred Malesian distribution patterns. Relationships between number of endemic species and surface area are significant for all species and for the majority of the families with significant species–area relationships. Main conclusions Species–area relationships of families appear to be dependent on species number. Families with high numbers of species usually have a significant species–area relationship whereas small families have not. For the families that display an eastern or western Malesian centred pattern, a historical biogeographical explanation should be invoked. Island surface area appears to be a predictor for island percent endemism in Malesian vascular plants. None of the islands appears to be a hotspot of endemism nor of species diversity, as no significant departure from the Arrhenius model was noted for any of them.  相似文献   

9.
It has been argued recently that the combination of male-only parental care and classical polyandry in birds is the most interesting and yet the least understood of all avian breeding systems. Despite a huge number of hypotheses, careful comparative analyses have repeatedly failed to identify consistent ecological differences between species showing male-only care and closely related species showing other patterns of care. This has led to the suggestion that such analyses fail because the crucial differences are between ancient lineages rather than between closely related species. Here, therefore, I use comparisons between families to test three well-known hypotheses: that male-only care is associated with: (i) a low rate of fecundity; (ii) large egg size relative to female size; or (iii) female-biased opportunities for remating. Families showing male-only care do not differ from families showing female-only care with respect to rate of fecundity or relative egg size. There is, however, a significant difference between these two groups of families with respect to an index of remating opportunities, nesting density. Families showing female-only care nest at high density, while those showing male-only care nest at very low density. This is one of the first times a consistent ecological correlate has been identified for male-only care in birds. It suggests that female-only care arises (or persists) in families where remating opportunities are abundant for both sexes, whereas male-only care arises (or persists) in families where remating opportunities are rare for both sexes and particularly scarce for males. This in turn suggests that sex differences in remating opportunities are the key ecological factor in determining male-only care and classical polyandry in birds.  相似文献   

10.
长白山区珍稀濒危观赏植物优先保护定量研究   总被引:7,自引:0,他引:7  
长白山区属温带气候,野生观赏植物资源十分丰富。经过7年的野外调查和查阅文献资料,首次建立了以蕴藏系数、保护缓急程度等9项指标在内的定量评价珍稀濒危观赏植物指标体系。结果表明:长白山区目前804种野生观赏植物中,受到生存威胁的观赏植物种类共有57科、129属、170种。其中急需保护的有27科、43属、52种,分别占长白山区科、属、种总数的47.39%、33.33%、30.59%,代表种类主要有长白松(Pinus sylvestriform is)、东北红豆杉(Taxus cuspidata)、朝鲜崖柏(Thuja koraiensis)等;需要保护的有32科、53属、62种,分别占科、属、种总数的56.14%,41.09%,36.47%,代表种类主要有牛皮杜鹃(Rhododendron chrysanthum)、木通马兜铃(Aristoloehia man-shuriensis)、花楸树(Sorbus pohuashanensis)等;一般保护的有36科、48属、56种,分别占科、属、种总数的63.16%,37.21%,32.94%,代表种类主要有芍药(Paeonia lactiflora)、长白瑞香(Daphne koreana)、溪荪(Iris sanguinea)等。  相似文献   

11.
Three anthocyanins were isolated from the red flowers of chenille plant, Acalypha hispida Burm. (Euphorbiaceae) by a combination of chromatographic techniques. Their structures were elucidated mainly by homo- and heteronuclear nuclear magnetic resonance spectroscopy and electrospray mass spectrometry, and supported with complete assignments of 13C NMR resonances. The novel pigment, cyanidin 3-O-(2"-galloyl-6"-O-alpha-rhamnopyranosyl-beta-galactopyranoside) (5%), contains the disaccharide robinoside. The other anthocyanins were identified as cyanidin 3-O-(2"-galloyl-beta-galactopyranoside) (85%), and cyanidin 3-O-beta-galactopyranoside (5%). Anthocyanins acylated with gallic acid have previously been identified in species from the families Nymphaeaceae and Aceraceae, and tentatively in Abrus precatorius (Leguminosae).  相似文献   

12.
13.
Long terminal retrotransposons are major components of eukaryotic transposable elements. We have surveyed the long terminal repeats (LTR) retrotransposons of domesticated silkworm (Bombyx mori) by mining the data produced by Bombyx mori Genome Sequencing Project. At least 29 separate families of LTR retrotransposons are identified in this survey, comprising of 11.8% of the complete sequence. Families of domesticated silkworm LTR retrotransposons can be mainly classified into three groups: gypsy-like, copia-like, Pao-Bel. Fourteen families identified consist of gypsy-like elements, four families consist of copia-like elements and seven families consist of Pao-Bel elements. In addition to the three groups of LTR retrotransposons, two families of unusual non-coding elements are identified in the genome of this species. Further phylogenetic analysis of RT domain indicates that the elements of B.mori show high diversity and can form different clades in each group. An analysis of sequence variation from different families reveals distinct patterns of variation for the elements belonging to three groups. The analysis of the domesticated silkworm LTR retrotransposons should assist in our understanding of the roles of retroelement in lepidopteron insect genome evolution.  相似文献   

14.
In prokaryotes, GC levels range from 25% to 75%, and Topt from approximately 0 degrees C to >100 degrees C. When all species are considered together, no correlation is found between the two variables. Correlations are found, however, when Families of prokaryotes are analysed. Indeed, when Families comprising at least 10 species were studied (a set of 20 Families), positive correlations are found for 15 of them. Furthermore, a comparative analysis by independent contrasts made within the Families in order to control for phylogenetic non-independence showed qualitatively equivalent results. We conclude that Topt is one of the factors that influences genomic GC in prokaryotes.  相似文献   

15.
通过野外实地调查,对广州市萝岗区风水林的植物组成及群落结构进行了分析.结果表明:萝岗区单个风水林面积为40 ~600 hm2,共有维管植物112科255属387种;其中,蕨类植物15科21属35种,裸子植物1科1属2种,被子植物96科233属350种;草本和乔木种类较多,分别有122和111种;灌木和藤本种类较少,分别有84和70种;其中,包含国家级珍稀保护植物5种和一些需要关注的种类,以及林下凤尾蕨(Pteris grevilleana Wall.ex Agardh)和虎克鳞盖蕨[Microlepia hookeriana (Wall.) Presl]2种广州市新记录种.优势科较明显,包含茜草科(Rubiaceae)、菊科(Compositae)、大戟科(Euphorbiaceae)、禾本科(Poaceae)、蝶形花科(Papilionaceae)、樟科( Lauraceae)等;虽然寡属科和寡种科所占比例较大,但包含种数较少;寡种属所占比例较大,占总属数的90.59%.植被类型属于南亚热带季风常绿阔叶林,以南亚热带常绿树种为主,可分为乔木层、灌木层和草本层,层间有丰富的藤本植物;作为群落的主体结构,木本植物较草本植物有优势.群落优势建群种主要为樟科、大戟科、壳斗科(Fagaceae)、山茶科(Theaceae)、胡桃科(Juglandaceae)和苏木科(Caesalpiniaceae)等科的种类,依据优势种不同可划分为13个群系.根据调查结果,对广州市萝岗区风水林的保护和资源利用提出了建议.  相似文献   

16.
A report and an updated list with comments on the species of freshwater molluscs of Argentina which covers an area of 2 777 815 km2 is presented. Distributions of Gastropoda and Bivalvia families, endemic, exotic, invasive as well as entities of sanitary importance are also studied and recommendations on their conservation are provided. Molluscs related to the Del Plata Basin have been thoroughly studied in comparison to others areas of the country. This fauna exhibits relatively the biggest specific richness and keeps its affinity with the fauna of other regions of the basin in areas of Paraguay and Brasil. The 4 500 records of molluscs considered in this paper arise from the study of the collections of Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", Buenos Aires; Museo de La Plata, La Plata and Fundación "Miguel Lillo", Tucumán. These institutions keep very important collections of molluscs in southern South America. Field information has recently been obtained and localities cited by other authors are also included in the data base. Until today, 166 species have been described, 101 belonging to 10 families of Gastropoda and 65 to 7 of Bivalvia. Families with highest specific richness are Lithoglyphidae (22) and Sphaeriidae (25), respectively. The number of endemic species (those present only in Argentina) by family is: Gastropoda: Ampullariidae (1), Cochliopidae (10), Lithoglyphidae (11), Thiariidae (3), Chilinidae (11), Lymnaeidae (2) and Physidae (2?); Bivalvia: Hyriidae (1?); Etheriidae (1?) and Sphaeriidae (10). Families with a distribution that comprise almost the whole country are: the Sphaeriidae and the gastropods Cochliopidae, Chilinidae and Lymnaeidae. Families Erodonidae and Solecurtidae (Bivalvia) were registered in mixohaline environments from Buenos Aires province. Gastropod families Thiaridae and Glacidorbiidae show a very restricted distribution. The rest of the families are present mainly in the center and north of the country. Species of sanitary interest are the propagators of: schistosomiasis -Biomphalaria peregrina, B. straminea y B. tenagophila, Planorbidae-, fasciolasis -Lymnaea viatrix and L. columnella, Lymnaeidae- and dermatitis -Chilina gibbosa and C. fluminea, Chilinidae. Invasive species are: Corbicula fluminea (Corbiculidae) and Limnoperna fortunei (Mytilidae). The construction of new areas for the protection and conservation of the high risk endemic species of freshwater molluscs is a priority. It is necessary to give special attention to the species of the patagonic mountain range and of the mesopotamic area of the Del Plata Basin.  相似文献   

17.
深圳市大鹏半岛蕨类植物区系及其生态特点   总被引:6,自引:1,他引:6  
深圳市大鹏半岛的蕨类植物共有105种,它们隶属于35科、65属。其中含5种以上的科有水龙骨科(Dryopteridaceae)、金星蕨科(Thely pteridaceae)、凤尾蕨科(Pteridaceae)、卷柏科(Selaginellaceae)、鳞毛蕨科(Dryopteridaceae)、蹄盖蕨科(Athy riaceae)、铁角蕨科(Aspleniaceae)、鳞始蕨科(Lindsaeaceae)。其区系具有较强的热带性质,科、属、种的分布区类型均以热带至亚热带为主,分别占总科数的54.26%,总属数的92.86%以及总种数的70.87%。单属科和单种属的比例较高,分别占总科数的54.26%,总属数的69.23%。按生长基质的不同,将大鹏半岛的蕨类植物划为土生、石生、水生和附生四种生态类型,其中以土生类型为主。  相似文献   

18.
武陵山区蕨类植物研究   总被引:6,自引:0,他引:6  
吴世福 《植物研究》1998,18(3):291-303
武陵山区蕨类植物资源丰富,现知有644种(包括变种),分属116属, 46科;蕨类区系属热带-亚热带山地类型;属的地理成份有12种类型,与日本、印度-马来西亚有密切关系;武陵山区蕨类区系属我国西南区系,与华中华东区关系密切,华南、华北区次之;蕨类垂直分布分四带。  相似文献   

19.
长白山区野生珍稀濒危药用植物资源评价体系的初步研究   总被引:30,自引:0,他引:30  
周繇 《西北植物学报》2006,26(3):599-605
长白山区属温带气候,野生药用植物资源十分丰富。经过6年的野外调查和查阅文献资料,首次建立了以蕴藏系数、保护缓急程度等7项指标在内的定量评价珍稀濒危药用植物指标体系。结果表明:长白山区目前1 004种(含变种、变型)野生药用植物中,受到生存威胁的药用植物种类共有59科、98属、124种。其中急需保护的有22科、30属、31种,分别占受威胁药用植物的科、属、种数的37.29%,30.61%,25%,代表种类主要有草苁蓉、人参、天麻、刺参、黄檗、平贝母等;需要保护的有29科、43属、53种,分别占受威胁药用植物的科、属、种数的49.15%,43.88%,42.74%,代表种类主要有高山红景天、木通马兜铃、刺五加、党参、辽细辛、北五味子等;一般保护的有34科、38属、40种,分别占受威胁药用植物的科、属、种数的57.63%,38.78%,32.26%,代表种类主要有穿龙薯蓣、祁州漏芦、黄花乌头、羊乳、手参、大叶小檗等。  相似文献   

20.
Variation in species and genus richness among families of flowering plants was examined with respect to four classification variables: geographical distribution, growth form, pollination mode, and dispersal mode. Previous studies have estimated rates of species proliferation from age and contemporary diversity. Here we found that the earliest appearances in the fossil record are correlated with contemporary familial species richness, abundance in the fossil record, and the independent variables considered in this analysis. Thus, we believe that the fossil record does not provide reasonable estimates of the ages of families and that the rate of species proliferation cannot be calculated from such data without bias. Accordingly, our subsequent analyses were based on contemporary species richness of families. Although the classification variables were interrelated, each made largely independent contributions to familial species richness. Cosmopolitan families were 5.6 times more species-rich than strictly tropical families and 35 times more species-rich than strictly temperate families. Families including both herbaceous and woody growth forms were 5.7 and 14 times more species-rich than families with either growth form alone. Although animal pollination was significantly associated with elevated familial species richness, the effect was statistically weak. The most prominent effect was that families with both abiotic and biotic dispersal had more than 10 times as many species as families with either dispersal mode alone. Our analyses also revealed that families having both dispersal modes were more likely to have several growth forms, suggesting that evolutionary flexibility of morphology may be generalized over diverse aspects of life history. These results do not support the idea that pollination and dispersal by animals were primarily responsible for the tremendous proliferation of angiosperm species, either by producing population structures conducive to speciation or by applying selection for diversification. Instead, the importance of varied dispersal mode, growth form, and climate zone in predicting high familial species richness suggests that a capacity to diversify morphologically and physiologically may have been primarily responsible for high rates of species proliferation in the flowering plants.  相似文献   

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