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1.
Vocalizations of Hainan partridges (Arborophila ardens) during the breeding season were studied, by making use of playback experiments, in Yinggeling Nature Reserve, Hainan Island, China. Both males and females were found to crow and to produce duet calls during the breeding season, and there was a sex difference in crowing as shown by spectrogram analyses. Both sexes responded strongly to simulated intrusion from pairs of conspecifics. However, it was found that males responded to intrasexual intrusion to a greater extent than to intersexual intrusion. Moreover, females responded strongly to both intra- and intersexual intrusion. Female-female response is proposed as a behavioral mechanism that favors monogamy in the Hainan partridge, and a generally high response to any kind of vocal stimuli indicates that females may play an important role in territory defense in this species. To our knowledge, this is the first report for female crowing in the genus Arborophila, and the second case for female crowing in the family Phasianidae.  相似文献   

2.
Anthropogenic global climate changes are one of the greatest threats to biodiversity. Distribution modeling can predict the effects of climate changes and potentially their effects on genetic diversity. DNA barcoding quickly identifies patterns of genetic diversity. As a case study, we use DNA barcodes and distribution models to predict threats under climate changes in the frog Nanorana parkeri, which is endemic to the Qinghai-Tibetan Plateau. Barcoding identifies major lineages W and E. Lineage W has a single origin in a refugium and Lineage E derives from three refugia. All refugia locate in river valleys and each greatly contributes to the current level of intraspecific genetic diversity. Species distribution models suggest that global climate changes will greatly influence N. parkeri, especially in the level of genetic diversity, because two former refugia will fail to provide suitable habitat. Our pipeline provides a novel application of DNA barcoding and has important implications for the conservation of biodiversity in southern areas of the Qinghai-Tibetan Plateau.  相似文献   

3.
四川山鹧鸪(Arborophila rufipectus)是中国西南山地特产珍稀鸟类,由于亚热带阔叶林破碎化,其种群数量显著下降。2005年11—12月在老君山自然保护区,共记录四川山鹧鸪非繁殖期栖息地20个。以其新鲜粪便为中心设一个10m×10m大样方和4个1m×1m的小样方,测量每个样方中与栖息地利用有关的12个生境因子(海拔、坡向、坡度、乔木层盖度、灌木高、灌木密度、灌木层盖度、竹盖度、竹密度、雪盖度、林缘距离和道路距离);并在距栖息地100m处任意设对照样方1—2个,共获取30个对照样方,测量相同的生境因子。结果表明,四川山鹧鸪非繁殖期以靠近林间小道和森林边缘的次生落叶阔叶林为栖息地,主要利用海拔高度为1000—1600m,坡度为2—15°的南坡;其偏爱的栖息地竹盖度、竹密度和雪盖度明显小于对照样方,而灌木盖度明显大于对照样方。对栖息地变量进一步分析表明,影响四川山鹧鸪栖息地利用的主要因子依次为地面层食物因子、地型因子、隐蔽因子、温度因子等,其中食物条件的贡献率为29.407%。四川山鹧鸪在利用栖息地时可能面对食物资源与天敌风险的权衡。因此,为了更好地保护四川山鹧鸪栖息地,应重视阔叶林的保护和恢复。  相似文献   

4.
The climatic cycles of the Quaternary, during which global mean annual temperatures have regularly changed by 5–10°C, provide a special opportunity for studying the rate, magnitude, and effects of geographic responses to changing climates. During the Quaternary, high- and mid-latitude species were extirpated from regions that were covered by ice or otherwise became unsuitable, persisting in refugial retreats where the environment was compatible with their tolerances. In this study we combine modern geographic range data, phylogeny, Pleistocene paleoclimatic models, and isotopic records of changes in global mean annual temperature, to produce a temporally continuous model of geographic changes in potential habitat for 59 species of North American turtles over the past 320 Ka (three full glacial-interglacial cycles). These paleophylogeographic models indicate the areas where past climates were compatible with the modern ranges of the species and serve as hypotheses for how their geographic ranges would have changed in response to Quaternary climate cycles. We test these hypotheses against physiological, genetic, taxonomic and fossil evidence, and we then use them to measure the effects of Quaternary climate cycles on species distributions. Patterns of range expansion, contraction, and fragmentation in the models are strongly congruent with (i) phylogeographic differentiation; (ii) morphological variation; (iii) physiological tolerances; and (iv) intraspecific genetic variability. Modern species with significant interspecific differentiation have geographic ranges that strongly fluctuated and repeatedly fragmented throughout the Quaternary. Modern species with low genetic diversity have geographic distributions that were highly variable and at times exceedingly small in the past. Our results reveal the potential for paleophylogeographic models to (i) reconstruct past geographic range modifications, (ii) identify geographic processes that result in genetic bottlenecks; and (iii) predict threats due to anthropogenic climate change in the future.  相似文献   

5.
Sichuan Hill Partridge (Arborophila rufipectus) is a globally endangered species endemic to China. However, the genetic diversity of this species was poorly studied due to lack of molecular markers. We used 454 pyrosequencing to discover microsatellites from the A. rufipectus genome in this study. A total of 6280 di-nucleotides, 8139 tri-nucleotides, and 11,987 tetra-nucleotides with sufficient flanking region for primer design were screened with in silico mining. Ultimately, 18 tetra-nucleotide polymorphic loci were first identified and used to examine the genetic diversity in the Laojunshan population. The number of alleles per locus ranged from 5 to 13, observed and expected heterozygosity varied from 0.292 to 0.917 and 0.722 to 0.909, respectively. These results revealed that this endangered species' genetic diversity as not as low as expected. However, a heterozygote deficit was found in the Laojunshan population. We proposed that the management should focus on increasing the connectivity of remnant patches and fragments to increase the opportunity of greater gene flow among fragmented populations of A. rufipectus. This is the first time that polymorphic microsatellite markers were reported for A. rufipectus. These markers provide a valuable resource for future population genetics studies and for the management and conservation of this species.  相似文献   

6.
Choice of variables, climate models and emissions scenarios all influence the results of species distribution models under future climatic conditions. However, an overview of applied studies suggests that the uncertainty associated with these factors is not always appropriately incorporated or even considered. We examine the effects of choice of variables, climate models and emissions scenarios can have on future species distribution models using two endangered species: one a short-lived invertebrate species (Ptunarra Brown Butterfly), and the other a long-lived paleo-endemic tree species (King Billy Pine). We show the range in projected distributions that result from different variable selection, climate models and emissions scenarios. The extent to which results are affected by these choices depends on the characteristics of the species modelled, but they all have the potential to substantially alter conclusions about the impacts of climate change. We discuss implications for conservation planning and management, and provide recommendations to conservation practitioners on variable selection and accommodating uncertainty when using future climate projections in species distribution models.  相似文献   

7.
Wang  R.Z. 《Photosynthetica》2004,42(1):71-79
Natural occurrence of C4 species, life forms, and their longitudinal distribution patterns along the Northeast China Transect (NECT) were studied. Six vegetation regions experiencing similar irradiation regimes, but differing in longitude, precipitation, and altitude were selected along the NECT from 108 to 131 °E, around altitude of 43.5 °N. Seventy C4 species were identified in 41 genera and 13 families. 84 % of the total C4 species were found in four families: Gramineae (38 species), Chenopodiaceae (11 species), Cyperaceae (5 species), and Amaranthaceae (5 species). C4 grasses make up 54 % of the total identified C4 species along the NECT and form the leading C4 family in meadow, steppe, and desert along the NECT. C4 Chenopodiaceae species make up about 16 % of the C4 species and become less important, particularly in the meadow and the eastern end of the NECT. 57 % of the total C4 species are therophytes and 37 % are hemicryptophytes, which is consistent with floristic composition and land utilization. In general, the number of C4 species decreased significantly from the west to the east or from dry to moist areas along the NECT, and was remarkably correlated with annual precipitation (r 2= 0.677) and aridity (r 2= 0.912), except for salinized meadow region. The proportion of C4 species from all the six vegetation regions was considerably correlated with these two climatic parameters (r 2= 0.626 or 0.706, respectively). These findings suggest that the natural occurrence of C4 species varies significantly along the large-scale longitudinal gradient of the NECT. The notable relationship of C4 species number and proportion in the flora with variations in annual precipitation and aridity suggest that these two climatic parameters are the main factors controlling the longitudinal distribution patterns of C4 species along the NECT.  相似文献   

8.
Environmental change drives demographic and evolutionary processes that determine diversity within and among species. Tracking these processes during periods of change reveals mechanisms for the establishment of populations and provides predictive data on response to potential future impacts, including those caused by anthropogenic climate change. Here we show how a highly mobile marine species responded to the gain and loss of new breeding habitat. Southern elephant seal, Mirounga leonina, remains were found along the Victoria Land Coast (VLC) in the Ross Sea, Antarctica, 2,500 km from the nearest extant breeding site on Macquarie Island (MQ). This habitat was released after retreat of the grounded ice sheet in the Ross Sea Embayment 7,500–8,000 cal YBP, and is within the range of modern foraging excursions from the MQ colony. Using ancient mtDNA and coalescent models, we tracked the population dynamics of the now extinct VLC colony and the connectivity between this and extant breeding sites. We found a clear expansion signal in the VLC population ~8,000 YBP, followed by directional migration away from VLC and the loss of diversity at ~1,000 YBP, when sea ice is thought to have expanded. Our data suggest that VLC seals came initially from MQ and that some returned there once the VLC habitat was lost, ~7,000 years later. We track the founder-extinction dynamics of a population from inception to extinction in the context of Holocene climate change and present evidence that an unexpectedly diverse, differentiated breeding population was founded from a distant source population soon after habitat became available.  相似文献   

9.
10.
The Lao newt (Laotriton laoensis) is a recently described species currently known only from northern Laos. Little is known about the species, but it is threatened as a result of overharvesting. We integrated field survey results with climate and altitude data to predict the geographic distribution of this species using the niche modeling program Maxent, and we validated these predictions by using interviews with local residents to confirm model predictions of presence and absence. The results of the validated Maxent models were then used to characterize the environmental conditions of areas predicted suitable for L. laoensis. Finally, we overlaid the resulting model with a map of current national protected areas in Laos to determine whether or not any land predicted to be suitable for this species is coincident with a national protected area. We found that both area under the curve (AUC) values and interview data provided strong support for the predictive power of these models, and we suggest that interview data could be used more widely in species distribution niche modeling. Our results further indicated that this species is mostly likely geographically restricted to high altitude regions (i.e., over 1,000 m elevation) in northern Laos and that only a minute fraction of suitable habitat is currently protected. This work thus emphasizes that increased protection efforts, including listing this species as endangered and the establishment of protected areas in the region predicted to be suitable for L. laoensis, are urgently needed.  相似文献   

11.
描述海南岛青冈属一新种—燕千青冈。  相似文献   

12.
琼桂地区短翼蚱科二新种(直翅目)   总被引:2,自引:0,他引:2  
记述采自海南及广西地区短翼蚱科2新种,即兴安大磨蚱Macromtettix xinganensis,sp,nov.及黑背波蚱Bolivaritettix,celaenotus,sp.nov..模式标本保存于陕西师范大学动物研究所昆虫标本室.  相似文献   

13.
14.
符国瑷  潘坤 《植物研究》2012,(3):257-259
海南岛发现(木兰科)含笑属二新植物。  相似文献   

15.
The importance of climatic conditions in shaping the geographic distribution of amphibian species is mainly associated to their high sensitivity to environmental conditions. How they cope with climate gradients through behavioral adaptations throughout their distribution is an important issue due to the ecological and evolutionary implications for population viability. Given their low dispersal abilities, the response to seasonal climate changes may not be migration, but behavioral and physiological adaptations. Here we tested whether shifts in climatic seasonality can predict the temporal variation of surface activity of the fossorial Lowland Burrowing Treefrog (Smilisca fodiens) across its geographical distribution. We employed Ecological Niche Modeling (ENM) to perform a monthly analysis of spatial variation of suitable climatic conditions (defined by the July conditions, the month of greatest activity), and then evaluated the geographical correspondence of monthly projections with the occurrence data per month. We found that the species activity, based on the species'' occurrence data, corresponds with the latitudinal variation of suitable climatic conditions. Due to the behavioral response of this fossorial frog to seasonal climate variation, we suggest that precipitation and temperature have played a major role in the definition of geographical and temporal distribution patterns, as well as in shaping behavioral adaptations to local climatic conditions. This highlights the influence of macroclimate on shaping activity patterns and the important role of fossorials habits to meet the environmental requirements necessary for survival.  相似文献   

16.
The paper presents a diatom succession in the Late Glacial and Holocene sediments of the Przedni Staw lake in the Pie Stawów Polskich Valley High Tatra Mts. Ten diatom phases are distinguished and presented against a pollen diagram from the analyzed core showing continuous sedimentation from the Oldest Dryas to the Subatlantic period. The diatom flora in the Late Glacial sediments is predominantly littoral — Fragilaria, Navicula, Nitzschia, Diploneis, Pinnularia and Amphora species. The Holocene sediments enclose more abundant planktonic species such as Cyclotella quadriiuncta, Asterionella formosa and Melosira distans.  相似文献   

17.
Seeds of the submerged vascular plants Najas marina, Najas minor and Najas flexilis are reported from submarine Holocene deposits from the southwestern part of the Baltic Sea, and we also report on a find of Najas minor from an Eemian deposit in Jutland, which is the first record of this species from the Eemian of Denmark. The common and widespread occurrence of especially the southern extralimital N. minor is indicative of higher than present summer temperatures during the period from 10300 to 8000cal.yearsBP.  相似文献   

18.
Climate change during the past five decades has impacted significantly on natural ecosystems, and the rate of current climate change is of great concern among conservation biologists. Species Distribution Models (SDMs) have been used widely to project changes in species’ bioclimatic envelopes under future climate scenarios. Here, we aimed to advance this technique by assessing future changes in the bioclimatic envelopes of an entire mammalian order, the Lagomorpha, using a novel framework for model validation based jointly on subjective expert evaluation and objective model evaluation statistics. SDMs were built using climatic, topographical, and habitat variables for all 87 lagomorph species under past and current climate scenarios. Expert evaluation and Kappa values were used to validate past and current models and only those deemed ‘modellable’ within our framework were projected under future climate scenarios (58 species). Phylogenetically-controlled regressions were used to test whether species traits correlated with predicted responses to climate change. Climate change is likely to impact more than two-thirds of lagomorph species, with leporids (rabbits, hares, and jackrabbits) likely to undertake poleward shifts with little overall change in range extent, whilst pikas are likely to show extreme shifts to higher altitudes associated with marked range declines, including the likely extinction of Kozlov’s Pika (Ochotona koslowi). Smaller-bodied species were more likely to exhibit range contractions and elevational increases, but showing little poleward movement, and fecund species were more likely to shift latitudinally and elevationally. Our results suggest that species traits may be important indicators of future climate change and we believe multi-species approaches, as demonstrated here, are likely to lead to more effective mitigation measures and conservation management. We strongly advocate studies minimising data gaps in our knowledge of the Order, specifically collecting more specimens for biodiversity archives and targeting data deficient geographic regions.  相似文献   

19.
Aim In this study we present a new view on the extinction of Myotragus balearicus, an extinct highly modified dwarf caprine from the Gymnesic Islands (or eastern Balearic Islands), as a methodological case study for interpretation of Late Quaternary extinctions (LQEs). Methods We analyse all available 14C ages obtained from M. balearicus bones from the uppermost part of the Pleistocene and the Holocene, together with the available chronological data of the putative causes of Myotragus extinction. Results It has been possible to define two critical dates that allow us to establish an ‘uncertainty period for the Myotragus extinction’ (UPME) in each analysed island (Mallorca, Menorca and Cabrera). For Mallorca, the UPME corresponds to the interval c. 3700 to 2030 calbc (i.e. c. 1670 years of uncertainty). In the case of Menorca, the UPME spans from 10,000 to 1930 calbc (8070 years of uncertainity). In Cabrera the UPME is placed between 3650 and 300 calbc (3350 years of uncertainty). These periods, together with a review of the available information on the chronology of human arrival and the chronology of Holocene climatic change, shed light on the possible causes of the extinction of this species. Main conclusions Extinction of Myotragus because of climatic change can be definitively rejected. The Myotragus extinction must be attributed to the rapid effects of the first human occupation. The use of uncertainity periods for the disappearance of species represents a useful tool for the analysis of LQEs.  相似文献   

20.
Species Distribution Models (SDMs) could be an important tool to limit search efforts by selecting the areas where field surveys are to be carried out; due to the constant decrease of financial funds, this challenging purpose is particularly necessary. In particular, these methods are useful when applied to endangered and/or rare species with a poor known distribution area, especially due to difficulties in plant detection and in reaching the study areas.We hereby describe the development of maximum-entropy (Maxent) models for the endangered yellow gentian Gentiana lutea L. in Sardinia with the aims of (i) guiding survey efforts; (ii) estimating SDMs utility by post-test species current/extinct localities through the Observed Positive Predictive Power (OPPP) values; and (iii) evaluating the influence of sample data addition. Besides the Area Under Curve (AUC) values, we used the OPPP (observed/modelled positive localities ratio) to compare results from eight, 24 and 58 presence-only data points. Even with the initial small and biased sample data, we found that surveys could be effectively guided using such methods, whereby the focus of our research was on 48% of our initial 721 km2 study area. The high OPPPs values additionally proved the reliability of our results in discovering 16 new localities of G. lutea. Nevertheless, the predictive models should be considered as a complementary tool rather than a replacement for expert knowledge.  相似文献   

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