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Peter D.  Gabbutt 《Journal of Zoology》1966,150(2):165-181
A new pseudoscorpion, Chthonius (Ephippiochthonius) kewi sp. n., was collected at Colne Point, Essex. The deutonymph, tritonymph and adults are described in detail, particular attention being paid to the chaetotaxy. Its taxonomic status is discussed, and keys are provided to allow its inclusion among both the European and British species. The significance of the changes in the chaetal series during development is discussed in relation to the taxonomy of the genus.  相似文献   

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The International Union for the Conservation of Nature (IUCN) Red List of ecosystems and Red List of threatened species are global standards for assessing risks of ecosystem collapse and species extinction. However, misconceptions of the Red List assessment process, along with its technically demanding nature, can result in the misapplication of their criteria, leading to inconsistent and potentially unreliable assessments. To address this problem, we developed redlistr, an R package aiding in the production of consistent species and ecosystem Red List assessments. Redlistr's features include methods to calculate 1) area from spatial data, 2) range size metrics, 3) rates of change of distributions or populations, and 4) distribution or population at another time from these rates. A key feature of the package is the systematic approach used to eliminate geometric uncertainty when estimating area of occupancy. Here, we develop two case studies to demonstrate the functionalities of redlistr with typical workflows for both species and ecosystems. Redlistr was developed to be accessible to users with a broad range of experience in programming for spatial and temporal data analysis, and sufficiently flexible to allow users to parameterise functions and select equations to fit their purposes. The package specifically aims to assist researchers and conservation practitioners to conduct robust and transparent risk assessments of ecosystems and species under the IUCN Red List criteria but is also useful for other studies requiring analyses of range size, area change and calculations of rates of change.  相似文献   

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Abstract. In order to stress successes in restoration and conservation of species, regionally, nationally or globally, a new instrument has been developed, the ‘Blue Lists’, ‘registers of those Red List species that show a durable overall stabilization or increase of abundance in the region (nation, world) considered’. ‘Blue Data Books’ include additional information on the ecology, conservation, and promotion of the species. For describing the overall change of abundance of every individual species six categories are defined. Furthermore, the effects of nature conservation techniques (NCT) on a species are evaluated using six additional categories. In a test area of 3 431 km2 in northern Switzerland, information was compiled on the change in abundance of the 708 Red List species of higher plants (spermatophyta) over the last 10-15 yr. Overall, 33% of these species showed a stabilization or even increase in abundance; these are Blue List species; ca.20% showed a decline and for almost 50% the change in abundance is not known. NCTs have been successfully applied to more than 50 % of all the species, at least locally. For about a further 30%, the required NCTs are known but have not yet been tried out. If these techniques were applied on a large scale, the decline of very many species in the test area could be stopped.  相似文献   

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Abstract.
  • 1 The bush crickets Platycleis albopunctata (Goeze) and Metriop-tera roeselii (Hagenbach) interact acoustically in the laboratory. The interaction is principally one-way, resulting in modification of the song pattern of P. albopunctata or its inhibition. Similarity of the frequency spectra of songs of both species is one of the principal reasons for reactivity.
  • 2 Nymphal male P. albopunctata individuals are randomly distributed in dense Brachypodium pinnatum L. grasslands. Adult males become regularly spaced with the onset of singing activity. Acoustic behaviour is the most likely mechanism maintaining regular spacing within the male P.albopunctata population.
  • 3 In many localities juvenile P. albopunctata and M. roeselii are sympatric, occurring together in the same vegetation.
  • 4 With the onset of singing activity by the adult males the two species separate though there is no detectable difference in habitat preference.
  • 5 The separation is effected by a negative phonotactic response by P. albopunctata to the song of M. roeselii. It is suggested that this response is derived from behaviour patterns that result in ‘territorial’ spacing within the P. albopunctata (male) population.
  • 6 This behaviour prevents the occurrence of song modification in the field but also excludes P. albopunctata from areas of suitable habitat where the population density of M. roeselii is high.
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Information contained on specimen labels of natural history collections is often the most reliable and available source of information to guide conservation decisions. When used for making IUCN Red List assessments, the inherent limitations associated with specimen information affect the assignment of Red List categories, and the case of the southern African plant Red Lists reflects this. Red List assessments that are based on specimen information can result in predictable outcomes, namely the tendency to assign the following categories: Data Deficient, Lower Risk-least concern, Vulnerable D2 or a threatened category using Criterion B. The reason for this is that specimen information satisfies distribution parameters of the IUCN system more readily than demographic parameters.  相似文献   

10.
A checklist of 137 liverwort and 445 moss species is established for Andorra based on a review of the literature and a long-term floristic survey. Five moss species, Barbula amplexifolia, Ditrichum zonatum, Grimmia donniana, Pohlia bulbifera, and P. lutescens, are new to the Iberian Peninsula. Another 7 liverwort and 156 moss species are new to Andorra. For each species, the distribution at the scale of 1?km2 and altitudinal range are documented, resulting in an improved assessment of the frequency and distribution of 101 moss species previously reported from a single record. Haplomitrium hookeri and Scapania verrucosa, which are the two Regionally Extinct species of the Spanish Red List of liverworts, occur in Andorra, which hosts between 23 and 37% of the species listed as Critically Rare, Endangered, or Vulnerable in the Spanish Red List of bryophytes. Therefore, it appears that Andorra is a key area for the conservation of the high-altitude flora of the Iberian Peninsula.  相似文献   

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The distribution of sulphate-reducing bacteria (SRB) in the sediments of the Colne River estuary, Essex, UK covering different saline concentrations of sediment porewater was investigated by the use of quantitative competitive PCR. Here, we show that a new PCR primer set and a new quantitative method using PCR are useful tools for the detection and the enumeration of SRB in natural environments. A PCR primer set selective for the dissimilatory sulphite reductase gene (dsr) of SRB was designed. PCR amplification using the single set of dsr-specific primers resulted in PCR products of the expected size from all 27 SRB strains tested, including Gram-negative and positive species. Sixty clones derived from sediment DNA using the primers were sequenced and all were closely related with the predicted dsr of SRB. These results indicate that PCR using the newly designed primer set are useful for the selective detection of SRB from a natural sample. This primer set was used to estimate cell numbers by dsr selective competitive PCR using a competitor, which was about 20% shorter than the targeted region of dsr. This procedure was applied to sediment samples from the River Colne estuary, Essex, UK together with simultaneous measurement of in situ rates of sulphate reduction. High densities of SRB ranging from 0.2 ? 5.7 × 108 cells ml? 1 wet sediment were estimated by the competitive PCR assuming that all SRB have a single copy of dsr. Using these estimates cell specific sulphate reduction rates of 10? 17 to 10? 15 mol of SO4 2 ? cell? 1 day? 1 were calculated, which is within the range of, or lower than, those previously reported for pure cultures of SRB. Our results show that the newly developed competitive PCR technique targeted to dsr is a powerful tool for rapid and reproducible estimation of SRB numbers in situ and is superior to the use of culture-dependent techniques.  相似文献   

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“The New Red List of the Italian Flora” includes all the Italian policy species and other species of known conservation concerns for a total of 400 taxa, 65% of which are threatened with extinction. The Red List is based on a huge georeferenced data-set useful for conservation purposes.  相似文献   

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The conservation status of Attacus wardi, a large iconic moth endemic to north-western Australia, is reviewed based on new data. Available evidence on the spatial distribution, critical habitat and threatening processes suggests the species qualifies as threatened according to IUCN Red List Criteria, and that its conservation status nationally should be revised from Endangered to Vulnerable. The species depends on relatively large patches of wet and dry coastal tropical monsoon forest, and it has the potential to be an important flagship species for the conservation of these ecological communities. Further studies are needed to determine minimum patch size and spatial connectivity among patches to support viable populations of the moth.  相似文献   

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Conservation management cannot proceed in the absence of the basic ecological data necessary to develop conservation strategies for a species. Species considered Data Deficient and possibly extinct are poorly known, and are often overlooked in conservation planning. This is despite a growing body of evidence indicating that Data Deficient species are more likely to be threatened by extinction compared to well-studied taxa. Hence, there is an immediate need to resolve data deficiency, and to search for species that are possibly extinct. Here, we conducted the first systematic search for a Data Deficient Australian skink, Lampropholis elongata (long sunskink), which prior to our study, had not been seen for approximately 9 years. A combination of pitfall trapping and active searches was used in attempt to detect the species. We rediscovered L. elongata at four sites within its known distribution on the southern edge of the New England Tablelands Bioregion in New South Wales, Australia. Our findings suggest that the species can be detected relatively easily using active survey methods, especially by inspecting tussock bases. We further highlight that areas of high canopy openness and high cover of Poa sieberiana (grey tussock-grass) appear to be key habitat for the species.  相似文献   

15.
Trapping at air temperatures close to, or exceeding, critical thermal maxima is important for comprehensive sampling of vertebrate assemblages and collection of sufficient data for impact assessment. However, pitfall trapping on hot days also potentially exposes trapped animals to stress or death through overheating or desiccation. We investigate causes of mortality from 14 305 captures over a 22‐year pitfall trap study in arid South Australia and compared mortality rates with maximum temperatures, solar radiation and rainfall. Overall mortality rate was 3.2% with chewing by rodents and handling accidents the most influential cause of death recorded. The highest mortality rates were experienced by the tiny skink, Lerista labialis, which was difficult to detect in traps each day and hence problematic to assess the effect of weather variables on capture mortality. For all other abundant species, high maximum temperature was only a significant explanatory variable for increased death rates of the house mouse Mus domesticus, and increased solar radiation was positively related to capture mortality for the house mouse, the frog Neobatrachus sudelli and the small skink Ctenotus schomburgkii. However, capture rates for these taxa and eight other common species would have been significantly lower if trapping did not occur on days of 40 °C or more. We conclude that trapping in hot weather is both desirable and justifiable and suggest techniques for further reducing mortality rates in pitfall studies.  相似文献   

16.
Abstract

The Australian giant bulldog ant Myrmecia brevinoda Forel was first observed in New Zealand in 1940 (Keall 1981). Further observations of this species were made at a location in Devonport in 1948 and 1965, and a nest destroyed at this site in 1981. Since this time no further observations have been made, yet the status of this species is commonly listed as “uncertain establishment” on New Zealand faunal lists. We describe the control procedure used in 1981. In addition, to determine its current status we resurveyed ants in the area of earlier infestation using visual searches, pitfall trapping, and a reward for discovery posted to local residents. No evidence of M. brevinoda was found, though several other invasive species were found, including the Argentine ant Linepithema humile (Mayr), Pheidole rugosula Forel, and a recently established Australian cryptic Solenopsis species. Given the results of our survey and the absence of other reports of M. brevinoda over the last 24 years, we consider this species to be extinct or eradicated from New Zealand.  相似文献   

17.
New records of the Japanese seahorse Hippocampus mohnikei from Cambodia, Malaysia, Thailand and Vietnam, along with recently published studies from India and Singapore, have greatly expanded the known range of H. mohnikei within Southeast Asia. These new records reveal novel habitat preferences and threats to H. mohnikei in the region. Although the global conservation status of H. mohnikei is classified as Data Deficient according to the IUCN Red List of Threatened Species, new sightings indicate that this species is found in similar habitats and faces similar threats as other Hippocampus species that are considered Vulnerable.  相似文献   

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The Red List Categories and the accompanying five criteria developed by the International Union for Conservation of Nature (IUCN) provide an authoritative and comprehensive methodology to assess the conservation status of organisms. Red List criterion B, which principally uses distribution data, is the most widely used to assess conservation status, particularly of plant species. No software package has previously been available to perform large‐scale multispecies calculations of the three main criterion B parameters [extent of occurrence (EOO), area of occupancy (AOO) and an estimate of the number of locations] and provide preliminary conservation assessments using an automated batch process. We developed ConR, a dedicated R package, as a rapid and efficient tool to conduct large numbers of preliminary assessments, thereby facilitating complete Red List assessment. ConR (1) calculates key geographic range parameters (AOO and EOO) and estimates the number of locations sensu IUCN needed for an assessment under criterion B; (2) uses this information in a batch process to generate preliminary assessments of multiple species; (3) summarize the parameters and preliminary assessments in a spreadsheet; and (4) provides a visualization of the results by generating maps suitable for the submission of full assessments to the IUCN Red List. ConR can be used for any living organism for which reliable georeferenced distribution data are available. As distributional data for taxa become increasingly available via large open access datasets, ConR provides a novel, timely tool to guide and accelerate the work of the conservation and taxonomic communities by enabling practitioners to conduct preliminary assessments simultaneously for hundreds or even thousands of species in an efficient and time‐saving way.  相似文献   

19.
通过野外调查、文献查阅、专家咨询及市场调查等手段获得长白山高山苔原带植物生存状况、分布数量的基本数据。在查阅文献的基础上,借助专家咨询构建了长白山高山苔原带植物受危等级、优先保护定量评估体系。该体系包含3个子系统,每个子系统下设不同指标共计12个。通过专家咨询法和层次分析法相结合的方法确定各子系统及各指标的权重。共评估植物94种,其中极危种3种,濒危种6种,易危种22种,近危种42种,无危种21种;在保护的缓急程度上,属于特级保护的有5种,一级保护的有6种,二级保护的有34种,三级保护的有30种,暂缓保护的有19种。评估结果与以往的红色名录进行了比较,一些从未列入红色目录的种类在本研究结果中有所体现。相反,有些曾被列入红色名录的物种在本次评估中被列为"无危"。对评估结果与以往红色名录之间产生差异种类及原因进行了讨论。  相似文献   

20.
Red Lists are widely used to indicate species at risk of extinction. Specimen sheets in herbaria provide an important source of data relevant for Red List assessments. The aims of this paper are to establish which data can be sourced from specimen information to satisfy IUCN Red Data List criteria and to identify the specific criteria that can be used. Red List parameters are measured within a Geographical Information System (GIS), as this provides an objective and repeatable methodology which is less subjective than manual methods. Data used to explore this were gathered during the course of preparing a monograph on Plectranthus (Lamiaceae). Criteria relating to distribution (extent of occurrence, area of occupancy and fragmentation) and population profile (projected continuing decline and number of subpopulations) proved most suitable for assigning categories of threat. Estimates of mature individuals, generation length, population size, population reduction, extreme fluctuation and number of locations could not be derived from herbarium material without making inconsistent subjective decisions. In addition to comprehensively databased specimen information, extensive field knowledge is required to produce better estimates for assessing extinction risk. In order to enhance the usefulness of specimen information in the future, improvements in recording additional botanical data at the time of collection would be beneficial. Overall, herbaria provide a useful starting point for conservation-related work and can help to guide future work.  相似文献   

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