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1.
Islands exhibit disproportionally high biodiversity, however high levels of endemism and simplified food webs make their communities susceptible to invasive species. Introduced goats (Capra hircus), a generalist herbivore, are among the most harmful invasive species on islands. Concern about goat impacts on island communities have resulted in eradication programs, which have been generally implemented without comprehensive evaluation and monitoring. Unintended consequences may follow eradication, as grazing can have complex effects on island food webs. Using whole island manipulations, we evaluate the long-term, community-wide effects of goat herbivory, as well as their subsequent removal, in a system of 16 islands in the Aegean Sea (Greece) located within the Mediterranean biodiversity hotspot. Goat grazing on these islands is a major conservation concern, as these support endemic plant communities that have evolved in low herbivory conditions and lack appropriate defenses. We show that goat introductions lead to significant decreases in vegetation height, percent cover, and biomass but not to immediate plant species loss, as native island endemics are replaced with widespread generalist taxa carried in by the livestock. Additionally, goats contribute to the desertification of islands by initiating a long-term soil loss cycle that continues even after goats are removed; however, remaining soil structure and chemistry are not affected. Island arthropod populations do not appear to be significantly impacted by goat introduction or removal, except for a distinct increase in the order Diptera with goat presence. This study also reaffirms the role of seabirds in providing important marine subsidies, rich in nitrogen and phosphorus, to island food webs. Plant species diversity declines following goat removal, and vegetation cover returns only partially, as further recovery is being prevented by the long-term loss of soil. This suggests that following goat removal, island communities may require additional restoration efforts, including seabird reestablishment and reintroduction of extirpated plant populations, to promote island recovery.  相似文献   

2.
3.
South Georgia has been the southernmost location where populations of invasive house mice Mus musculus are found. The distribution of mice was investigated at Cape Rosa and the Nuñez Peninsula, the two areas of South Georgia where the species is known to occur. Live-trapping and kill-trapping took place during March 2012, at the end of the austral summer, with traps in four grids (3.2–4.0 ha in area) and on 34 trap lines distributed across a range of habitats from the shoreline to 250 m above sea level. Mice were scarce, with just 68 captures in about 1750 trap nights. Mouse densities in tussock habitat were estimated at 2.1–2.8 mice/ha, with higher densities of 5.3–6.4 mice/ha along the coastline. Mice were found in all habitats apart from higher-altitude fellfield, but were relatively less abundant in tussock habitat with large numbers of seals. Mice were breeding at both sites with 58 % of mature females pregnant or lactating. Litter size (7.1 ± 2.3 embryos) and adult body mass (21.4 ± 4.6 g) were typical of most other island mice populations. Population densities of mice on South Georgia are two orders of magnitude lower than mouse densities measured at other sub-Antarctic islands. The very low population density and its restricted distribution, with most captures close to the shore, and the presence of large numbers of burrowing petrels and South Georgia pipits Anthus antarcticus at both sites, suggest that mice have a relatively limited impact on South Georgia’s vertebrate biodiversity.  相似文献   

4.
Extraction, thin layer chromatography and gas chromatography–mass spectrometry of Solena amplexicaulis (Lam.) Gandhi, commonly known as creeping cucumber, (Cucurbitaceae) leaves revealed 21 long-chain primary alcohols, and 100 g leaves indicated presence of 3651.59 ± 327.18 SE µg long-chain primary alcohols. 1-Heptadecanol and 1-triacontanol were the predominant and least abundant primary alcohols, representing for 780.44 ± 42.59 and 3.28 ± 0.55 SE μg, respectively. Antibacterial property of the complete synthetic blend (0.1%), comparable to long-chain alcohols as detected by GC-FID of 100 g S. amplexicaulis leaf extracts was evaluated on the pathogenic bacteria Salmonella gallinarum by agar well diffusion method, and exhibited 20.4, 26.7 and 38.2 mm zone of inhibition at 25, 50 and 100 μl doses, respectively. One hundred µl dose of 6 individual pure synthetic compounds, 1-tridecanol, 1-pentadecanol, 1-heptadecanol, 1-nonadecanol, 1-eicosanol and 1-tricosanol comparable to the amounts present in 0.1% solution of pure isolated alcohols from S. amplexicaulis leaves displayed 16.2, 17.7, 18.6, 22.8, 15.8 and 14.5 mm zone of inhibition against this bacterium, respectively. Hundred µl dose from a synthetic blend of above 6 compounds (comparable to the proportions as present in 0.1% solution of pure isolated alcohols from 100 g S. amplexicaulis leaves) exhibited 38.1 mm zone of inhibition against this bacterium. Furthermore, 100 μl dose from a mixture (1:1) comprising of chloramphenicol (1 µg/ml) and a synthetic blend of above 6 compounds displayed 38.8 mm inhibition zone against S. gallinarum, and hence, this combination might be used against this pathogenic bacteria.  相似文献   

5.
The concentration of cadmium in human tissues obtained on the basis of autopsies of non-poisoned Polish people (n = 150), aged from 1 to 80 years, examined between 1990 and 2010, is presented. The following values were found in wet digested samples by flame atomic absorption spectrometry (FAAS) (mean ± SD, median, and range, μg/g of wet weight): brain 0.020 ± 0.031, 0.084, 0–0.120 (n = 41); stomach 0.148 ± 0.195, 0.084, 0–1.25 (n = 89); small intestine 0.227 ± 0.231, 0.130, 0–0.830 (n = 39); liver 1.54 ± 1.55, 1.01, 0.015–9.65 (n = 99); kidney 16.0 ± 13.2, 14.0, 0.62–61.3 (n = 91); lung 0.304 ± 0.414, 0.130, 0–1.90 (n = 25); and heart 0.137 ± 0.107, 0.140, 0.017–0.250 (n = 4). Additionally, results (n = 13 people, aged from 2 to 83 years, 63 samples) obtained by inductively coupled plasma optical emission spectrometry (ICP OES) between 2010 and 2015 are given. The obtained data on Cd concentration in the human body can be used to estimate the amounts occurring in “healthy” people and those occurring in cases of chronic or acute poisonings with Cd compounds, which are examined for forensic purposes or to assess environmental exposure levels.  相似文献   

6.
Trypanosomiasis is a neglected tropical disease of both livestock and humans. Although pastoral communities of the Maasai Steppe have been able to adapt to trypanosomiasis in the past, their traditional strategies are now constrained by changes in climate and land regimes that affect their ability to move with their herds and continually shape the communities’ vulnerability to trypanosomiasis. Despite these constraints, information on communities’ vulnerability and adaptive capacity to trypanosomiasis is limited. A cross-sectional study was therefore conducted in Simanjiro and Monduli districts of the Maasai Steppe to establish pastoralists’ vulnerability to animal trypanosomiasis and factors that determined their adaptation strategies. A weighted overlay approach in ArcGIS 10.4 was used to analyze vulnerability levels while binomial and multinomial logistic regressions in R 3.3.2 were used to analyze the determinants of adaptation. Simanjiro district was the most vulnerable to trypanosomiasis. The majority (87.5%, n = 136) of the respondents were aware of trypanosomiasis in animals, but only 7.4% (n = 136) knew about the human form of the disease. Reported impacts of animal trypanosomiasis were low milk production (95.6%, n = 136), death of livestock (96.8%, n = 136) and emaciation of animals (99.9%, n = 136). Crop farming was the most frequently reported animal trypanosomiasis adaptation strategy (66%, n = 136). At a 95% confidence interval, accessibility to livestock extension services (β = 7.61, SE = 3.28, df = 135, P = 0.02), years of livestock keeping experience (β = 6.17, SE = 1.95, df = 135, P = 0.001), number of cattle owned (β = 5.85, SE = 2.70, df = 135, P = 0.03) and membership in associations (β = ? 4.11, SE = 1.79, df = 135, P = 0.02) had a significant impact on the probability of adapting to animal trypanosomiasis.  相似文献   

7.
Native forests on oceanic islands are among the most threatened ecosystems. The forests formed on Sekimon uplifted limestone in Haha-jima Island (Ogasawara Islands) have not yet been destroyed by human activities and remain as primary forests harboring several narrow endemic endangered plants. In this paper, we described the plant species diversity, community structure, and status of invasion by alien plants in the mesic forests of Sekimon. The Sekimon forest was characterized by low tree diversity (37 species), high stem density (1731 ha?1), and high basal area (63.9 m2 ha?1), comparing with natural forests in world islands. The forests were dominated in the number of stems by the sub-tree Ardisia sieboldii followed by the trees Pisonia umbellifera and Elaeocarpus photiniifolius. The invasive tree Bischofia javanica ranked fourth for basal area and third for the number of stems (DBH?≥?10 cm), and its distribution expanded, especially near a past plantation site. Surveys of forest floor vegetation revealed that species richness of vascular plants was 109 species and that many alien plants had already invaded the forests. Despite the low species richness of alien (16% for vascular flora and 8% for trees), the high frequency of aliens on the forest floor suggests that they have colonized successfully in the Sekimon forest. Extrapolation analysis based on the rarefaction curves predicted that the vascular plants in the Sekimon (25 ha) accounted for 135 species (29.9% of the vascular flora of the Ogasawara Islands) and endemic plants were 85 species (62.0%). The fact that the 39 vascular species recorded in our plots were listed in Japanese Red List suggests that the Sekimon forest should be conserved as a sanctuary of biodiversity. Because alien plants are invading the forests without apparent anthropogenic disturbance, immediate action to eradicate these invaders is highly needed.  相似文献   

8.
We investigate the timing of diversification in allopolyploids of Nicotiana (Solanaceae) utilising sequence data of maternal and paternal origin to look for evidence of a lag phase during which diploidisation took place. Bayesian relaxed clock phylogenetic methods show recent allopolyploids are a result of several unique polyploidisation events, and older allopolyploid sections have undergone subsequent speciation at the polyploid level (i.e. a number of these polyploid species share a singular origin). The independently formed recent polyploid species in the genus all have mean age estimates below 1 million years ago (Ma). Nicotiana section Polydicliae (two species) evolved 1.5 Ma, N. section Repandae (four species) formed 4 Ma, and N. section Suaveolentes (~35 species) is about 6 million years old. A general trend of higher speciation rates in older polyploids is evident, but diversification dramatically increases at approximately 6 Ma (in section Suaveolentes). Nicotiana sect. Suaveolentes has spectacularly radiated to form 35 species in Australia and some Pacific islands following a lag phase of almost 6 million years. Species have filled new ecological niches and undergone extensive diploidisation (e.g. chromosome fusions bringing the ancestral allotetraploid number, n = 24, down to n = 15 and ribosomal loci numbers back to diploid condition). Considering the progenitors of Suaveolentes inhabit South America, this represents the colonisation of Australia by polyploids that have subsequently undergone a recent radiation into new environments. To our knowledge, this study is the first report of a substantial lag phase being investigated below the family level.  相似文献   

9.
The coconut hispine beetle, Brontispa longissima (Gestro), supposedly originated from Papua New Guinea and Indonesia but has recently invaded Southeast and East Asian countries where it has been causing serious damage to Cocos nucifera L. This insect also occurs on the Southwest Islands off Kyushu Island in Japan. To evaluate the potential northward range expansion of this insect in Japan, we investigated its cold tolerance at 0, 5, and 10 °C (egg, larva, pupa, and adult), 13 °C (adult), and 15 °C (egg and hatched larva). At 15 °C, few eggs hatched, and the larvae that hatched died within a few days of hatching. At 13 °C, Ltime95 was estimated to be 23 days for adults, with the most cold-tolerant developmental stage at 10 °C. At all developmental stages, Ltime95 of B. longissima was estimated to be 19 days at 10 °C, 8 days at 5 °C, and 5 days at 0 °C, suggesting the cold tolerance of this beetle is very low. Considering average daily temperatures, it is unlikely that B. longissima can establish itself north of Amami-Oshima Island, located in the far south off the main island of Japan.  相似文献   

10.
The southern giant petrel (Macronectes giganteus) has a circumpolar distribution and breeds on subantarctic islands and a few continental Antarctic sites. Although this species has recently been down-listed to “Least Concern” by the World Conservation Union (IUCN), there are strong fluctuations in abundance and variable long-term trends recorded at different sites. Systematic, long-term monitoring is essential to determine drivers underlying its population dynamics. Here, we examine long-term changes in population size and productivity of southern giant petrels at Signy Island, South Orkney Islands. Comparing estimated numbers of breeding pairs over the whole island in 2000/2001, 2005/2006, 2009/2010 and 2014/2015 with historical data revealed several phases of population change: a 64 % decline (6.2 % per annum) from 1968/1969 to 1984/1985, a 162 % increase (6.2 % per annum) to 2000/2001, stability until 2005/2006, a 56 % decline (18.3 % per annum) to 2009/2010 and stability until 2014/2015. This represents a 1.8 % decline per annum between 1968/1969 and 2014/2015. Annual counts within focal study areas suggested a more rapid increase from 1996/1997 to 2006/2007, but the same downward trend from 2006/2007 to present, underlining potential pitfalls in inferring trends from part-island counts. There was also a 20 % decline in breeding success from 1996/1997 to 2014/2015. Our results indicate substantial fluctuations in southern giant petrel abundance at Signy Island over 4–5 decades and a recent decline in breeding numbers and success. As the southern giant petrels breeding at the South Orkney Islands represents ~5–10 % of the global population, continuation of these declines would be of high conservation concern.  相似文献   

11.
In this study, we combined remote sensing data and in situ observations to explore the potential habitats of macroalgae at Libukang Island, Indonesia. High-resolution satellite images from the GeoEye-1 were used to estimate and to map the geomorphological structures together with macroalgal species in the study area. Seasonal variations of percentage cover and biomass of macroalgae associated with substrates were investigated in May and November 2014, and June 2015, using quadrats as sampling unit. A total of nine common genera were found in the study area with three dominant genera: Sargassum, Padina, and Turbinaria. Most of macroalgae was observed in the eastern part of the Island, on several substrate types and particular oceanographic conditions (wave and current). Mean biomasses of Sargassum and Padina were high in May (1189.6 ± 455 and 166.7 ± 15.4 g DW.m?2, respectively), while the biomass of Turbinaria was high in November (3245 ± 599.8 g DW.m?2). The map accuracy of image classification for all typology substrates was 74.19%. Overall, approximately 62.3% of the total study area can be considered as potential for natural macroalgae habitats. Spectral response characteristic of shallow water substrates at study area based on GeoEye-1 is also presented. The results of this study exhibit a potential utilization of natural macroalgae in the study area, and provide information for a possible diversification of the use of macroalgae in Indonesia. The method could be useful for habitat management and future biomonitoring in the study area or other similar areas in Indonesia.  相似文献   

12.
Hybridisation between an endangered species and a more common species can facilitate population decline and extinction of the endangered species due to wasted reproductive effort, outbreeding depression and/or swamping of alleles due to widespread or complete admixture. The Chatham Island black robin (Petroica traversi) is an endangered songbird species, which was reduced to only five individuals in 1980. Intensive cross-fostering, whereby black robin offspring were placed into nests of the closely related Chatham Island tomtit (Petroica macrocephala chathamensis) to increase reproductive output, contributed to the rapid recovery of the species within 10 years. Several hybridisation events occurred and although those hybrids were successfully eliminated from the population, concerns remained for the possibility of introgression between the two species that may have gone unnoticed. In this study, we genotyped seven microsatellite loci in both species from the two islands where they coexist, to assess the level of hybridisation and the extent of introgression between the two species. The two species shared no alleles at five of the seven loci genotyped, and cluster analysis, AMOVA and admixture analysis of a total of 174 black robins and 78 Chatham Island tomtits showed no evidence of hybridisation or introgression on either of the two islands where they co-exist. As a result, there is no evidence that black robins are currently in any danger of population decline or extinction through hybridisation with tomtits, although small population size and skewed sex ratio, particularly in the smaller of the two populations, may facilitate future hybridisation events.  相似文献   

13.
Analyzing chromosomal traits is one of the pragmatic ways to establish evolutionary and genetic database of plants that has complicated phylogenetic system. There are some conflicts on the exact phylogeny and evolutionary pathway of Lilium, and section martagon is the most complicated part among them. In this study, chromosomal traits of martagon lily species are described. All martagon lilies were analyzed with FISH (Fluorescence in situ hybridization) technique, followed by detailed karyotyping. Each species showed 2n = 2x = 24 of chromosome complement. Size of chromosomes ranged from 451.04 to 680.06 µm. 5S and 45S ribosomal DNA, general molecular markers in modern evolutionary research were used as probe in this study. Variation in rDNA loci and chromosome translocation were observed in Lilium hansonii; the highest number of 45S rDNA loci was detected in Lilium hansonii, followed by other martagon lilies, in similar locations but with differences, and chromosome translocation was observed from one individual of Lilium hansonii. Additionally, Lilium tsingtauense from Jeju-do Island, Korea was detected with two extra chromosomes. These kind of genetic variations through karyotyping indicate ongoing genetic variations in martagon lilies. In this study, precise analysis of chromosome traits in Lilium species belonging to section martagonperformed to contribute to better comprehension of the evolutionary pathway and establishment of cytogenetic database for further plant breeding research.  相似文献   

14.
The behavior of polar deep-sea nekton is very poorly known. To obtain insight into mating behavior of the abundant and ecologically important sub-Antarctic deep-sea squid Onykia ingens, our goals were to (1) quantify spermatophore production; (2) determine the preferred location for spermatangia deposition; (3) investigate whether male and female O. ingens mate with multiple mates; and (4) discuss the location of implanted spermatangia in light of mating behavior and egg fertilization. Toward this end, we examined male and female O. ingens specimens from Falkland Island and New Zealand waters. Male O. ingens store up to 198 spermatophores (mean 103 ± 61; n = 12) in their reproductive system, which are produced over a period of considerable somatic growth (200–400 mm ML), and which may have a considerable size range. Males insert their long extendible terminal organ in the mantle cavity of the female, potentially through the funnel, to deposit spermatophores in one or more of four regions on the female’s body. Most implanted spermatangia (52.5 %) were found in the funnel region, but many were also found inside the mantle cavity closer to the oviducts. Males with longer terminal organs therefore may be able to position closer to the oviducts where fertilization chances are higher than for spermatangia located in the funnel region. The number of implanted spermatangia per individual female (4–60, mean 29 ± 20; n = 24), the multiregional spermatangia deposition, and the different outer appearance of spermatangia, suggested that females have multiple mating events. Since males produce more spermatophores (up to 200) than the number of spermatangia in one region (<60), it is likely that males too mate with more than one female. We show how quantitative assessment of reproductive characteristics can provide insight into the reproductive behavior of deep-sea species for which in situ observations are currently lacking.  相似文献   

15.
A new species of labrid fish Oxycheilinus samurai sp. nov. is described on the basis of five specimens from the Ryukyu Islands, Japan, and Panay Island, the Philippines. The new species is most similar to the Indo-West Pacific species Oxycheilinus orientalis in having a slender compressed body, 12 pectoral-fin rays, a blackish blotch around the anterior portion of the lateral-line anterior series, and a dark blotch basally on the membrane between the first and second dorsal-fin spines. However, O. samurai can be distinguished from O. orientalis by the following combination of characters: gill rakers 4 + 7–8; snout rounded with maximum circumference 49.8–63.5 % of standard length (SL); interorbital width 7.7–9.2 % of SL; caudal-peduncle depth 13.8–15.3 % of SL; posterior margin of caudal fin white; black or dark red area just before white posterior margin of caudal fin; poorly defined blackish blotches on inner surface of opercle in preserved specimens.  相似文献   

16.
We characterized the foraging behavior and habitat associations of lactating female northern fur seals (Callorhinus ursinus) from two of four rookeries comprising the stable population on the Commander Islands (CI). The CI females included in the study were from Severo-Zapadnoe rookery (SZR in 2008 and 2009) and Servernoe rookery (SR in 2009) which are 16 km apart on the northern tip of Bering Island (BI). We used satellite-linked tags and time–depth recorders to track the animals at sea and record dive behavior. For SZR females, the average foraging trip duration, mean dive depth, and maximum travel distance for both years were 3.4 ± 1.42 days, 16 ± 9.8 m, and 85 ± 59.6 km, respectively. The same measures for SR females were 4.4 ± 1.90 days, 20 ± 9.7 m, and 159 ± 70.8 km, respectively. The mean duration of foraging trips, mean number of bouts per trip and trip duration, mean direction of foraging trips, and size of foraging areas were significantly different between females from SR and SZR. Foraging trips of females from neither rookery were associated with high chl-a concentration. Overall, females on the CI appeared to expend less time and energy during foraging trips than females on the Pribilof Islands, and this may explain why the latter population is declining while the CI population is stable.  相似文献   

17.
作为典型的陆桥岛屿, 千岛湖成为检验栖息地片段化理论的自然研究平台。2011年5月1日至2014年3月31日, 我们在千岛湖32个岛屿和1个大陆对照样点布设了60台红外相机, 对千岛湖体型较大的地栖兽类及其最小监测时长进行了监测和研究。在27,798个相机日的监测中, 共获得动物影像照片23,639张, 照片清晰、可进行物种鉴定的有2,414张, 占照片总数的10.2%; 其中体型较大的地栖兽类独立照片988张, 识别为9个物种: 穿山甲(Manis pentadactyla)、黄麂(Muntiacus reevesi)、野猪(Sus scrofa)、华南兔(Lepus sinensis)、马来豪猪(Hystrix brachyuran)、猪獾(Arctonyx collaris)、鼬獾(Melogale moschata)、花面狸(Paguma larvata)和豹猫(Prionailurus bengalensis), 平均独立照片拍摄率为40.9%。种-面积曲线研究表明, 岛屿上的地栖兽类物种丰富度随着岛屿面积的增大而增大, 曲线的z值为0.27。大岛(>10 ha)中, 最小监测时长随面积增加而增加, 而小岛没有明显趋势; 最小监测时长随隔离度增加而减小, 但关系不显著(d.f. = 20, F = 3.067, P = 0.095), 表明建湖后栖息地的片段化与岛屿化导致了一些对面积或栖息地较为敏感的大型兽类在小岛屿上的局部灭绝。因此, 我们建议对于面积较大的片段化栖息地, 红外相机应保证较长的最小监测时长, 而面积较小的片段化栖息地在监测中应根据隔离度、基质性质、物种种类适时调整调查强度, 以完整反映当地物种实际情况。  相似文献   

18.
In order to elucidate the causes for the increased mortality of aged patients with bacterial central nervous system (CNS) infections, we compared the course of Streptococcus pneumoniae (S. pneumoniae) meningitis in aged and young mice. Aged (21.2?±?3.1 months, n?=?40) and young (3.2?±?0.9 months, n?=?42) C57BL/6N and B6/SJL mice were infected by intracerebral injection of 50–70 CFU S. pneumoniae serotype 3 and monitored for 15 days. Aged and young mice did not differ concerning mortality (35% versus 38%), weight loss, development of clinical symptoms, bacterial concentrations in cerebellum and spleen as well as the number of leukocytes infiltrating the CNS. In contrast to results from our geriatric mouse model of Escherichia coli (E. coli) meningitis, where aged mice showed a higher mortality and an impaired elimination of bacteria, we did not find any differences between aged and young mice after intracerebral infection with S. pneumoniae serotype 3. This indicates that the increased susceptibility of aged mice to bacterial CNS infections is pathogen-specific: It appears less prominent in infections caused by hardly phagocytable pathogens with thick capsules like S. pneumoniae serotype 3, where the age-related decline of the phagocytic capacity of microglia and macrophages has a minor influence on the disease course.  相似文献   

19.
Despite the significance of biological invasions in the Antarctic region, understanding of the rates of spread and impact of introduced species is limited. Such information is necessary to develop and to justify management actions. Here we quantify rates of spread and changes in impact of the introduced wasp Aphidius matricariae Haliday, which parasitizes the invasive aphid Rhopalosiphum padi (L.), on sub-Antarctic Marion Island, to which the wasp was introduced in ca. 2001. Between 2006 and 2011, the wasp had colonised all coastal sites, with an estimated rate of spread of 3–5 km year?1. Adult abundance doubled over the period, while impact, measured as mean percentage parasitism of R. padi, had increased from 6.9 to 30.1 %. Adult wasps have thermal tolerances (LT50s) of between ?18 and 33.8 °C, with a crystallization temperature of ?22.9 °C, and little tolerance (ca. 37 h) of low humidity at 10 °C. Desiccation intolerance is probably limiting for the adult wasps, while distribution of their aphid host likely sets ultimate distributional limits, especially towards higher elevations where R. padi is absent, despite the presence of its host grass on the island, Poa cookii (Hook. f.). Rising temperatures are benefitting P. cookii, and will probably do the same for both R. padi and A. matricariae. Our study shows that once established, spread of introduced species on the island may be rapid, emphasizing the importance of initial quarantine.  相似文献   

20.
Many species of the butterfly genus Phengaris are regarded as endangered in many parts of their distribution. Several species are also widely distributed across northern China. Due to land use change and overgrazing, their habitats are declining and many patches have been lost. This paper investigates the distribution and habitats of the Chinese Phengaris species (of the subgenus Maculinea). Shrub-grassland near forests seem the most frequent habitat for Phengaris, while flat open grasslands are mostly over-grazed and thus survival for Phengaris butterflies there seems difficult. Throughout Europe, P. teleius is an endangered species, while there is still no information on its status in China. To improve the knowledge on the population ecology of P. teleius, its population structure, adult behaviour and movement were studied through mark–release–recapture methods in the Qinling Mountains of Taibai County. Eight grassland patches which were potentially suitable were found in the area in 2013. In total, 480 individuals (274 females) were marked, resulting in an overall recapture rate of 16 %. The average daily population size was 44 butterflies (±23 SD) during the adult flight period. Sixty-seven percent of the females and 38 % of the males moved less than 50 m, and 17 % of recaptured females and 38 % of males moved more than 200 m. The mean movement distance was 107 ± 177 m for males and 182 ± 122 m for females. The majority of the recaptures (86 %) were made within the patches, only a few individuals (14 %) moved between patches. Due to human disturbance and destruction, all of the eight potentially suitable patches are becoming smaller and increasingly isolated, thus these populations of P. teleius may face an increasing risk of extinction, which may well be a tip of the iceberg of habitat loss and fragmentation of P. teleius in Taibai County and possibly beyond. Hence we hope our initial study of P. teleius could have positive impacts on the conservation of Phengaris butterflies in China.  相似文献   

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