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1.
The first record of Misgurnus anguillicaudatus in Germany 总被引:1,自引:0,他引:1
Oriental weatherfish Misgurnus anguillicaudatus , from southern China, have been imported to Germany in large numbers for the garden pond trade. The first record of M. anguillicaudatus from Central Europe, a population that has been established for at least 14 years in a small nature reserve in Germany, is detailed. 相似文献
2.
Christina M. Giovas Michelle J. LeFebvre Scott M. Fitzpatrick 《Journal of Biogeography》2012,39(3):476-487
Aim This paper investigates the prehistoric introduction of five mammalian taxa to Carriacou (Lesser Antilles) and refines the known anthropogenic ranges for these fauna in the pre‐Columbian West Indies. The importance of such records for understanding the region’s historical biogeography and ecology is considered. Location Carriacou Island, Grenada (12°28′ N, 61°26′ W). Methods Zooarchaeological assemblages from Carriacou’s earliest documented prehistoric sites, Grand Bay and Sabazan, were analysed, and exotic taxa were identified and quantified. The timing of introductions was established based on multiple radiocarbon assays, including three new accelerator mass spectrometry (AMS) direct dates obtained on the bone of exotic taxa. Source species and location(s) are considered and compared with known prehistoric records for the Caribbean to synthesize anthropogenic distributions for the pre‐Columbian period. The contexts of the zooarchaeological remains are evaluated to better understand the nature and purpose of introductions. Results Zooarchaeological investigation on Carriacou reveals the occurrence of multiple mammal introductions from South American between c. ad 700 and ad 1400. This paper presents the first records for guinea pig (Cavia sp.), armadillo (Dasypus sp.), peccary (Tayassu/Pecari sp.), opossum (Didelphis sp.) and agouti (Dasyprocta sp.) from the island. Human‐mediated transport of these taxa is indicated by their absence from the record prior to human settlement of Carriacou. Several translocated species are either rare or entirely unknown for the region, and overall West Indian distributions are temporally and spatially discontinuous. Archaeological contexts indicate that mammalian introductions arose from human subsistence needs, but other social factors may have shaped the dispersal of these fauna. Main conclusions The taxonomic combination and richness of Carriacou’s introduced fauna are unusual within the region. Importantly, the new records significantly improve the known pre‐Columbian geographic range for peccary, guinea pig and armadillo. Integrated with regional records, these data augment our understanding of the Caribbean’s historical biogeography, and have the potential to improve our understanding of human mobility and anthropogenic environmental impacts in the West Indies prior to the arrival of Europeans. 相似文献
3.
A Lacoursière-Roussel DG Bock ME Cristescu F Guichard P Girard P Legendre CW McKindsey 《Molecular ecology》2012,21(17):4227-4241
The relative importance of multiple vectors to the initial establishment, spread and population dynamics of invasive species remains poorly understood. This study used molecular methods to clarify the roles of commercial shipping and recreational boating in the invasion by the cosmopolitan tunicate, Botryllus schlosseri. We evaluated (i) single vs. multiple introduction scenarios, (ii) the relative importance of shipping and boating to primary introductions, (iii) the interaction between these vectors for spread (i.e. the presence of a shipping-boating network) and (iv) the role of boating in determining population similarity. Tunicates were sampled from 26 populations along the Nova Scotia, Canada, coast that were exposed to either shipping (i.e. ports) or boating (i.e. marinas) activities. A total of 874 individuals (c. 30 per population) from five ports and 21 marinas was collected and analysed using both mitochondrial cytochrome c oxidase subunit I gene (COI) and 10 nuclear microsatellite markers. The geographical location of multiple hotspot populations indicates that multiple invasions have occurred in Nova Scotia. A loss of genetic diversity from port to marina populations suggests a stronger influence of ships than recreational boats on primary coastal introductions. Population genetic similarity analysis reveals a dependence of marina populations on those that had been previously established in ports. Empirical data on marina connectivity because of boating better explains patterns in population similarities than does natural spread. We conclude that frequent primary introductions arise by ships and that secondary spread occurs gradually thereafter around individual ports, facilitated by recreational boating. 相似文献
4.
Résumé Le parasitePauesia cedrobii Stary et Leclant, spécifique du puceron du CèdreCedrobium laportei Remaudière, a été récolté dans le Moyen-Atlas, (Maroc) puis introduit dans un peuplement de cèdre (Cedrus atlantica Manetti) du sud-est de la France au printemps 1981. La méthode utilisée a consisté en une introduction directe des parasites,
préalablement isolés sur le lieu de récolte (momies) puis mis à éclore en chambre climatisée de fa?on à éliminer les hyperparasites.
Après accouplement, 225 adultes ont été introduits dans des manchons installés sur des rameaux abritant des colonies deC. laportei. L'évolution des populations de l'h?te et du parasite a été suivie au niveau des points de lacher d'une part, et dans la
parcelle d'autre part. L'installation définitive du parasite dans la parcelle s'est produite, 1 an après le lacher, grace
à un automne et à un hiver particulièrement doux, qui ont favorisé la multiplication de l'h?te. Le parasite est définitivement
implanté: il est encore présent 4 années après le lacher. Entre temps, il a été étendu à d'autres forêts de cèdre du sud-est
de la France. Huit espèces d'hyperparasites autochtones se sont portés surP. cedrobii, mais ceci ne remet pas en cause la réussite de l'introduction de l'aphidiide.
Avec la collaboration technique deE. Robert, A. Chalon, J. Chizky. 相似文献
5.
ABSTRACT.
- 1 A study was made of the insect species present on twenty-eight colonies of H.chamaecistus Mill, in 1978 ranging in size (cover) from 0.4 m2 to about 6500 m2 and separated from nearest large neighbours by distances up to 6.5 km. Twenty-three insect species were collected of which nine or ten were more or less monophagous.
- 2 There was a clear relationship between species richness and size of host colony. Sites with less than 30 m2 of rock-rose, about 67% of those in the study area, were likely to have less than half of the monophagous species. Distance to neighbouring colonies did not contribute significantly to species richness.
- 3 The consistency of results from year to year was examined at five sites re-sampled in 1979. The 1978 data were also used to compare‘expected’and observed faunas at five new sites sampled in 1979 based upon the species-area relationship and the relative frequency of species at known sites.
- 4 Insect dispersal was examined using a suction trap placed near the largest rock-rose site. Colonization of new sites was studied by experimental outplanting of pot-grown plants.
- 5 These direct observations, and the monitoring of fourteen sites for 5 years, suggested that colonization and interchange of faunas were rare events. The experimental introduction of one to five species at four sites showed in several cases that the sites were suitable for the species, and that introduction could significantly enhance a site's complement.
6.
农业生态系统中新物种引进的初步探讨 总被引:5,自引:0,他引:5
在现有的农业生态系统中,引进某些新物种,往往可以使整个系统的功能发生变化。如果新物种引进得当,则可产生良好的效果,系统功能得以改善,效益提高;反之,则会造成人力、物力、财力的损失,削弱系统的功能,甚至可能遗患无穷。因此,对农业生态系统中 相似文献
7.
桑白蚧恩蚜小蜂Encarsia(=Prospaltella)berlesel(Howard)是寄生桑白蚧Pseudaulacaspls pentagona(Targioni-Tozzctti)的重要寄生蜂,许多国家进行了引进移植,对控制桑白蚧的为害取得明显的成效.本记述了桑白蚧恩蚜小蜂形态特征的鉴别。以及各国引进利用的概况.并讨论了利用寄生蜂防治桑白蚧的重要性. 相似文献
8.
Rafael Muñoz-Mas Franz Essl Mark van Kleunen Hanno Seebens Wayne Dawson Christine Marie V. Casal Emili García-Berthou 《Global Ecology and Biogeography》2023,32(9):1632-1644
Aim
Investigating major freshwater fish flows (translocations) between biogeographic regions and their temporal dynamics and also quantifying spatial patterns and temporal changes in the array of introduced species, and the emergence and distance between major donor and recipient regions.Location
Global.Time Period
1800–2020.Major Taxa Studied
Freshwater fishes.Methods
We analysed a global dataset on freshwater fish introductions (4241 events of 688 species). Freshwater fish flows were investigated with flow diagrams and χ2 tests, while PERMANOVA (permutational multivariate analysis of variance) was used to test the association between species and regions and temporal shifts. Cluster analysis revealed major recipient areas and composition of the introduced species. Finally, changes in distances between donor and recipient sites were tested with PERMANOVA.Results
The number of introductions between biogeographic regions mirrored the European and North American dominance before World War II (WWII) and the trends in recreational fishing, biocontrol programmes and food production, especially in the Sino-Oriental region, which has a long tradition of aquaculture and fishkeeping. Over the years, the origins and composition of introduced species changed uniquely in each biogeographic region, although the most introduced species are common to every region. Salmonids and other cold-water species were frequently introduced before the 1950s, whereas tropical ornamental and aquaculture species currently prevail. Distances between donor and recipient sites did not vary over the time. After WWII, the Sino-Oriental region consolidated its dominance and the Ethiopian and Neotropical regions emerged as new global donor and recipient regions.Main Conclusions
Global policy should focus on tropical ornamental and aquaculture species, which could benefit from global warming, especially in the Sino-Oriental region, because it currently dominates freshwater fish species flows, and the Ethiopian and Neotropical regions, because they recently emerged as important global donor and recipient regions of freshwater fish introductions. 相似文献9.
10.