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1.
A. F. A. Hawkins 《Journal of Biogeography》1999,26(3):447-458
Aim To describe variation in forest bird communities with altitude and latitude. Location Eastern Madagascar. Methods Extraction of data from forest bird inventories conducted in eastern Madagascar. Results There is a strong decline in species richness with altitude, above about 1300 m. Below this altitude, species richness is about constant or declines slightly. Seventy-eight percent of species occurring regularly in forest are absent from at least one of low, mid-altitude or high altitude forest. Of eighty-seven species occurring regularly in forest, only four or possibly five have latitudinally limited distributions, over a latitudinal range of over 1200 km. Three or possibly four are limited to the northern two-thirds, and one appears to be at least much more common in the southern half. Main conclusions Eastern Malagasy rain forest birds show previously unanalysed variation in altitudinal distribution. There is much less latitudinal variation. Species currently considered threatened are concentrated in the lowland and high-altitude zones. This may be at least partly due to lack of survey effort giving the impression that these species are rare, but lowland forests at least are under great human pressure. Bird conservation initiatives would probably have most effect if targeted at lowland east Malagasy rain forest. 相似文献
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Geographical and seasonal influences on the distribution of fungal endophytes in Quercus ilex 总被引:2,自引:0,他引:2
A systematic survey of the endophytic assemblages of Quercus ilex in central Spain has been performed, with the goal of evaluating the importance of geographical and seasonal factors on these fungal communities. Four sampling sites were selected; one of them was sampled twice, in the spring and the autumn. The collected plant material consisted of bark, twigs and leaves from eight trees per site. Fungal strains were isolated with the use of a surface-sterilization method with sodium hypochlorite. A total of 2921 fungal strains grouped into 149 'species' or morphological types were recovered. The 10 dominant species, with isolation frequencies >1.5%, were Pyrenochaeta sp., Periconiella anamorph of Biscogniauxia mediterranea (De Not.) Kuntze, Pseudonectria sp., Cryptosporiopsis quercina Petrak, Alternaria alternata (Fr:) Keissl., two undetermined coelomycetes, Penicillium funiculosum Thom, Diplodia mutila Fr. apud Mont. and Ascochyta sp. Medians of fungal species per tree were significantly different among the sampled sites. The isolation frequencies of the dominant species, as well as other less frequent species, were significantly dependent on the sampling site. The degree of endophytic infection and the diversity of fungal species were significantly higher in the spring. The frequencies of all dominant species at one of the sites depended significantly on the season, except for C. quercina , Acremonium sclerotigenum (F & V Moreau ex Valenta) Gams. and D. mutila . Cluster analysis of the whole endophytic mycoflora of the sampled trees suggested that the geographical factor affects the endophytic distribution patterns more significantly than the seasonal factor. 相似文献
3.
R. Terry Chesser 《The Journal of animal ecology》1998,67(1):69-77
1. Patterns of distribution of breeding austral migrant tyrant-flycatchers in temperate South America were quantified and analysed in conjunction with a variety of ecological, biogeographical and climatic variables.
2. The pattern of proportion of migratory to total breeding tyrannids was most strongly associated with latitude and two temperature variables, mean temperature of the coldest month and relative annual range of temperature.
3. The strong associations of latitude and temperature with percentage of migrants are consistent with the results of most similar investigations of the breeding distributions of migratory birds, both for migrants breeding in North America and in Europe, but contradict the hypothesis that habitat complexity plays a major role in structuring the proportion of migrants in communities of breeding birds.
4. The consistency of results among studies of migrants on different continents suggests that temperature and latitude, presumably a surrogate for one or more climatic variables, are globally significant factors in the breeding distributions of migratory birds.
5. The results for austral migrant flycatchers are consistent with the hypothesis that the prevalence of migration at any particular locality is ultimately dependent on the abundance of resources in the breeding season and the severity of the winter season, or on the difference in resource levels between summer and winter. 相似文献
2. The pattern of proportion of migratory to total breeding tyrannids was most strongly associated with latitude and two temperature variables, mean temperature of the coldest month and relative annual range of temperature.
3. The strong associations of latitude and temperature with percentage of migrants are consistent with the results of most similar investigations of the breeding distributions of migratory birds, both for migrants breeding in North America and in Europe, but contradict the hypothesis that habitat complexity plays a major role in structuring the proportion of migrants in communities of breeding birds.
4. The consistency of results among studies of migrants on different continents suggests that temperature and latitude, presumably a surrogate for one or more climatic variables, are globally significant factors in the breeding distributions of migratory birds.
5. The results for austral migrant flycatchers are consistent with the hypothesis that the prevalence of migration at any particular locality is ultimately dependent on the abundance of resources in the breeding season and the severity of the winter season, or on the difference in resource levels between summer and winter. 相似文献
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The rate at which migrant birds replenish their energy stores at intermittent stopovers largely determines overall migration
speed, the manner in which migration proceeds and success of migration. In this study, data on the fuel deposition rate (FDR)
of three long-distance migrants from 17 ringing sites along their autumn migration route were used to examine: (1) effects
of endogenous factors on FDR, and (2) how relationships between exogenous factors and FDR affect the organisation of migration.
We developed a model to estimate FDR from retrapped birds which takes into account time of day and various other factors which
might influence FDR. The two endogenous factors, moult and current energy stores, generally reduced FDR. This may result in
lower departure energy loads and more stopovers than expected from optimal migration theory. Differences between species with
respect to seasonal, year-to-year and geographical patterns of FDR could be related to differences in availability and predictability
of food resources, and help to explain differences in the organisation of migration. A low FDR in northern and central Europe
could be related to low, but predictable, food resources and an early departure during moult of the reed warbler (Acrocephalus scirpaceus); FDRs varying between years were related to large spatial and year-to-year variation in the density of the main prey of
the sedge warbler (Acrocephalus schoenobaenus); and a high FDR in the garden warbler (Sylvia borin) was related to abundant food resources, due to a switch from a purely invertebrate diet to a mixed diet including fruits
which are abundant over large areas of Europe and north Africa. This study demonstrated that the organisation of migration
is the outcome of a complex interplay of the seasonal timing of moult, food availability and predictability and a seasonal
switch in diet, and can be modified by individual birds in response to a limited amount of time in which to migrate.
Received: 26 April 1999 / Accepted: 24 September 1999 相似文献
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Climatic adaptations in the Drosophila immigrans species group: seasonal migration and thermal tolerance 总被引:2,自引:0,他引:2
Abstract. 1. In central Japan, Drosophila curviceps Okada and Kurokawa was collected in spring and autumn but not in summer at lowlands (alt. 500–1200 m), while it was collected only in summer at highlands (1500–2000 m). Experiments on its thermal tolerance suggested that summer heat at the lowlands and winter low temperatures at the highlands were adverse to this species. It is considered that this species escapes from these extreme temperatures by undergoing seasonal migration between the lowlands and the highlands. This species had no photo-periodic diapause and bred at both lowlands and highlands.
2. D.immigrans Sturtevant was less cold-hardy but more heat-tolerant than D.curviceps. It is considered that this species is unable to overwinter outdoors at least in the study areas (i.e. alt. 500m or higher in central Japan) and its populations in these areas originate with migrants from warmer areas.
3. D.albomicans Duda, a subtropical species, was less cold-hardy but more heat-tolerant than the above two species.
4. Climatic adaptations and distributions of these species are discussed with reference to their thermal tolerance. 相似文献
2. D.immigrans Sturtevant was less cold-hardy but more heat-tolerant than D.curviceps. It is considered that this species is unable to overwinter outdoors at least in the study areas (i.e. alt. 500m or higher in central Japan) and its populations in these areas originate with migrants from warmer areas.
3. D.albomicans Duda, a subtropical species, was less cold-hardy but more heat-tolerant than the above two species.
4. Climatic adaptations and distributions of these species are discussed with reference to their thermal tolerance. 相似文献
8.
Winger BM Lovette IJ Winkler DW 《Proceedings. Biological sciences / The Royal Society》2012,279(1728):610-618
Seasonal migration in birds is known to be highly labile and subject to rapid change in response to selection, such that researchers have hypothesized that phylogenetic relationships should neither predict nor constrain the migratory behaviour of a species. Many theories on the evolution of bird migration assume a framework that extant migratory species have evolved repeatedly and relatively recently from sedentary tropical or subtropical ancestors. We performed ancestral state reconstructions of migratory behaviour using a comprehensive, well-supported phylogeny of the Parulidae (the 'wood-warblers'), a large family of Neotropical and Nearctic migratory and sedentary songbirds, and examined the rates of gain and loss of migration throughout the Parulidae. Counter to traditional hypotheses, our results suggest that the ancestral wood-warbler was migratory and that losses of migration have been at least as prevalent as gains throughout the history of Parulidae. Therefore, extant sedentary tropical radiations in the Parulidae represent losses of latitudinal migration and colonization of the tropics from temperate regions. We also tested for phylogenetic signal in migratory behaviour, and our results indicate that although migratory behaviour is variable within some wood-warbler species and clades, phylogeny significantly predicts the migratory distance of species in the Parulidae. 相似文献
9.
An overview of the Tipulidae known to occur in northern Morocco with an emphasis on the Rif mountains is given, incorporating new distribution data based on recently collected material in the area. Dolichopeza (Dolichopeza) hispanica, Tipula (Lunatipula) subpustulata, and Tipula (Yamatotipula) afriberia afriberia are recorded for the first time for the Rif. Tipula (L.) stimulosa Mannheims, 1973 and T. (Vestiplex) vaillanti vaillanti Theowald, 1977 are reported for the first time for the Rif and Morocco. Tipula (Lunatipula) pseudocinerascens Strobl, 1906 and Tipula (Savtshenkia) confusa van der Wulp, 1883 are recorded for the first time for the Rif, Morocco and North Africa. A new species of the subgenus Lunatipula, T. (L.) pjotri n. sp., is described and illustrated. Nephrotoma exastigma, previously reported for the Rif, seems to be absent in Morocco. Reports of Tipula (Emodotipula) obscuriventris Strobl, 1900 for Morocco actually refer to T. (E.) leo. This brings the number of Tipulidae for Morocco to 39 species and for the Rif to 28. An updated checklist of the Tipulidae of Morocco is provided. 相似文献
10.
Acantholycosa azarkinaesp. n. is described from the Maritime Province of Russia on the basis of both sexes. Acantholycosa norvegica (Thorell, 1872) is reported from the Maritime Province for the first time. A key and illustrations to all six species that occur in Far East Asia are provided. 相似文献
11.
One hundred and thirty species of Cladocera have been recorded from the Indian subcontinent which extends from 6°N to 37°N latitude and covers an area of 4.5 million km2. The equatorial region has few Daphnia species, all belonging to the sub-genus Ctenodaphnia while the more northern parts have more species of Daphni including Daphnia s. str. The limnetic Cladocera lacks the carnivorous Polyphemidae and Leptodoridae at lower latitudes (equatorial). The common limnetic species of the equatorial region are eurytopic and extend throughout the subcontinent. 相似文献
12.
Ecological processes are changing in response to climatic warming. Birds, in particular, have been documented to arrive and breed earlier in spring and this has been attributed to elevated spring temperatures. It is not clear, however, how long-distance migratory birds that overwinter thousands of kilometers to the south in the tropics cue into changes in temperature or plant phenology on northern breeding areas. We explored the relationships between the timing and rate of spring migration of long-distance migratory birds, and variables such as temperature, the North Atlantic Oscillation (NAO) and plant phenology, using mist net capture data from three ringing stations in North America over a 40-year period. Mean April/May temperatures in eastern North America varied over a 5°C range, but with no significant trend during this period. Similarly, we found few significant trends toward earlier median capture dates of birds. Median capture dates were not related to the NAO, but were inversely correlated to spring temperatures for almost all species. For every 1°C increase in spring temperature, median capture dates of migratory birds averaged, across species, one day earlier. Lilac (Syringa vulgaris) budburst, however, averaged 3 days earlier for every 1°C increase in spring temperature, suggesting that the impact of temperature on plant phenology is three times greater than on bird phenology. To address whether migratory birds adjust their rate of northward migration to changes in temperature, we compared median capture dates for 15 species between a ringing station on the Gulf Coast of Louisiana in the southern USA with two stations approximately 2,500 km to the north. The interval between median capture dates in Louisiana and at the other two ringing stations was inversely correlated with temperature, with an average interval of 22 days, that decreased by 0.8 days per 1°C increase in temperature. Our results suggest that, although the onset of migration may be determined endogenously, the timing of migration is flexible and can be adjusted in response to variation in weather and/or phenology along migration routes. 相似文献
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中国十字花科(Cruciferae)的地理分布 总被引:9,自引:0,他引:9
在评述十字花科(Cruciferae)分类系统,分析主要性状演化趋势和科、属分布的基础上,提出中国十字花科植物可能是本土起源的观点,其起源中心和分布中心可能在以青藏高原为主体的西部高山和丘陵地区,起源时间至少在第三纪晚期以前,并认为中国十字花科植物自起源地(青藏高原)可能有3条主要的散布途径:第1条是自青藏高原向东北部,沿宁夏、陕西、内蒙古、山西、河北,到达东北大小兴安岭一带,并在蒙古高原及东北山地形成次分布中心;第2条自青藏高原向东,经重庆、湖南、湖北,沿长江流域分布,到达东部沿海一带;第3条自青藏高原向东南部,经贵州、广西、广东、福建,延伸到台湾。 相似文献
16.
Claude Besuchet 《法国昆虫学会纪事》2013,49(1-2):155-172
The species belonging to Tychus rufus group are revised. Eleven species are recognized, described and illustrated and a key to their identification is provided. Nine taxa are new to science: Tychus carpathius n. sp. from Karpathos island (Greece); T. torticornis n. sp. from Lesbos Island (Greece); T. pisidicus n. sp. and T. inermis n. sp. from southwestern Turkey; T. antiocheus n. sp. and T. effeminatus n. sp. from southeastern Turkey; T. artvinensis n. sp. from northeastern Turkey, and T. sidonicus n. sp. and T. libanus n. sp. from Lebanon. 相似文献
17.
To understand the global distribution patterns of litter-dwelling thrips, a total 150 leaf litter samples were collected from 6 natural reserves located in three climatic regions, temperate, subtropical and tropical. The results showed the relative abundance of Thysanoptera was over 3.0% in 4 natural reserves from subtropical and tropical zone, and reached 5.9% in one tropical reserve, only less than Acarina and Collembola. In contrast it was only 0.3% in the warm temperate natural reserves, and no thrips were collected in a mid temperate reserve. The order on the average species numbers per plot of litter thrips was tropic > subtropics > temperate (n=25, p<0.05). Mean density of litter thrips per plots in the tropics and subtropics was significantly higher than that in the temperate region (n=25, p<0.05), but the average density was not significantly different between tropical and subtropical zones (n=25, p>0.05). The diversity of litter thrips in the tropics and subtropics was much higher than that in the temperate area based on comparsions of Shannon-Wiener diversity index (H’), Pielou eveness index (J), and Simpson dominance index (D). All of these results indicated that litter-dwelling thrips lived mainly in tropical and subtropical regions; meanwhile, species number and relative abundance increased with decreasing latitude. 相似文献
18.
Influence of climate change on the abundance, distribution and phenology of woodland bird species in temperate regions 总被引:1,自引:1,他引:1
There is now overwhelming evidence that an increase in the concentration of greenhouse gases in the Earth's atmosphere has caused global temperatures to increase by 0.6 °C since 1900 and further increases of between 1.4 and 5.8 °C are predicted over the next century. Changes in climatic conditions have already influenced the demography, phenology and distribution of a wide range of plant and animal taxa. This review focuses on the impacts, both observed and potential, of climate change on birds breeding in temperate woodlands of the Western Palaearctic, a significant proportion of which are currently declining. Changes in ambient temperatures and patterns of precipitation may have direct and indirect effects on the survival rates and productivity of bird species, thus influencing population sizes. For some species or populations, the timing of events such as egg-laying and return from the wintering grounds is also changing in relation to shifts in the peak of food availability during the breeding season. The degree to which different individuals are able to track these temporal changes will have a significant bearing on population sizes and distributions in the future. Unless active management steps are taken, the relatively low dispersal rates of tree species may lead to a decrease in the total area of some woodland habitat types as losses at the southern edge of the range are likely to occur much more quickly than expansion at the northern edge. In addition, the dispersal rates of many woodland birds are themselves low, which could affect their ability to move to new habitat patches if currently occupied areas become unsuitable. Thus, woodland birds may be particularly susceptible to the impacts of climate change. 相似文献
19.
The genus name Limnobaris Bedel is applied in a restricted sense to baridine weevils with a covered pygidium and non-prominent, decussate mandibles which occur on sedges in the Palaearctic Region and immediately adjacent parts of tropical Southeast Asia. Calyptopygus Marshall and Pertorcus Voss are syn. n. of Limnobaris. Some species from Africa and the Americas are maintained provisionally in Limnobaris in the widest sense but will need to be transferred to other genera in future studies. A total of eleven species is recognized in Asia, two of which are widespread and occur also in the Western Palaearctic Region. Limnobaris martensi Korotyaev sp. n. is described from Nepal. Pertorcus tibialis basalis Voss is raised to species rank, as L. basalis (stat. prom.). New or reestablished synonyms are L. dolorosa (Goeze) (= L. jucunda Reitter, = L. koltzei Reitter), L. tibialis (Voss) (= Pertorcus tibialis pilifer Voss) and L. t-album (Linnaeus) (= L. bedeli Reitter, = Baridius crocopelmus Gyllenhal, = L. sahlbergi Reitter, = L. scutellaris Reitter, = Baris t-album sculpturata Faust). Calandra uniseriata Dufour is considered a junior synonym of Sitophilus oryzae (L.) (syn. n.). A key for identification and a distribution map are provided. 相似文献
20.
中国前胡属酯酶同工酶与种类演化和地理分布格局 总被引:3,自引:2,他引:3
利用聚丙烯酰胺凝胶电泳方法分析比较我国前胡属(PeucedanumL.)18种4变种的叶片酯酶同工酶酶谱,并结合形态特征和地理分布,从基因位点分布规律出发,探讨该属种间亲缘关系和地理分布格局。前胡属种类的酯酶同工酶酶谱能较好地反映种间的亲缘关系,基因位点随所分析种类的地理分布而呈现出明显的地带性变化。讨论了滨海前胡(P.japonicumThunb.)、马山前胡(P.mashanenseShanetSheh)和广西前胡(P.guangxienseShanetSheh)、石防风〔P.terebinthaceum(Fisch.)Fisch.exTurcz.〕和宽叶石防风〔P.terebinthaceumvar.deltoideam(MakinoexYabe)Makino〕、红前胡(P.rubricauleShanetSheh)和刺尖前胡(P.elegansKomarov),以及华中前胡(P.medicumDunn)和华北前胡(P.harrysmithiiFeddeexWolff)等种类的酯酶同工酶酶谱类型与系统演化的关系。根据前胡属植物区系,将我国前胡属分成7个酯酶同工酶地理表型。 相似文献