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1.
Environmental pollution is currently identified as one of the major drivers of rapid decline of insect populations, and this finding has revitalized interest in insect responses to pollution. We tested the hypothesis that the pollution-induced decline of insect populations can be predicted from phenotypic stress responses expressed as morphological differences between populations inhabiting polluted and unpolluted sites. We explored populations of the brassy tortrix Eulia ministrana in subarctic forests along an environmental disturbance gradient created by long-lasting severe impacts of aerial emissions of the copper–nickel smelter in Monchegorsk, northwestern Russia. We used pheromone traps to measure the population densities of this leafrolling moth and to collect specimens for assessment of three morphological stress indices: size, forewing melanization, and fluctuating asymmetry in wing venation. Wing length of E. ministrana increased by 10%, and neither forewing melanization nor fluctuating asymmetry changed from the unpolluted forest to the heavily polluted industrial barren. However, the population density of E. ministrana decreased 5 to 10 fold in the same pollution gradient. Thus, none of the studied potential morphological stress indicators signaled vulnerability of E. ministrana to environmental pollution and/or to pollution-induced environmental disturbance. We conclude that insect populations can decline without any visible signs of stress. The use of morphological proxies of insect fitness to predict the consequences of human impact on insect populations is therefore risky until causal relationships between these proxies and insect abundance are deciphered.  相似文献   
2.
Abstract

The shrublands growing on siliceous and/or calcium-poor substrata of the hilly and mountainous areas of north-western and central Italy were studied. This secondary vegetation is dominated by several acidophilous shrubs like Ulex europaeus, Cytisus scoparius, Erica arborea, E. scoparia and Calluna vulgaris. The synecology, synchorology and syntaxonomy of this vegetation was studied using multivariate methods, and discussed in comparison with similar types described in other zones of the Italian peninsula. Two new subassociations are proposed here: Erico arboreae-Arbutetum unedonis genistetosum germanicae and Calluno-Sarothamnetum ericetosum scopariae. Calluno-Sarothamnetum is typified; the Sarothamnion alliance is discussed and referred to Cytisetea scopario-striati. The presence of Calluno-Ulicetea and Cytisetea scopario-striati classes is discussed, and a syntaxonomical scheme is proposed.  相似文献   
3.
R. H. L. Disney 《ZooKeys》2013,(342):45-74
64 species of Phoridae, in 6 genera, are reported from the Kola Peninsula, north of the Arctic Circle. The new species Megaselia elenae and Megaselia kozlovi are described. 33 species of Megaselia, only known from females, are given code numbers. Keys to the species of all the females of Megaselia and Phora are provided; and also a key to the males European Megaselia species with a notopleural cleft.  相似文献   
4.
The butterfly fauna on the Korean peninsula are comprised of both the Palearctic and Oriental species. We hypothesized that the Oriental species (immigrated across the sea) tend to have a wider niche breadth compared with the Palearctic species (immigrated from the continent) since the former migrates long distances across the sea and has to adapt to new environments. We tested this hypothesis using Korean butterfly data on distribution, habitat, food and life history traits. The distribution and ecological traits such as habitat breadth, overwintering stage, and voltinism of the Oriental species were found to be significantly different from the Palearctic species. However, the diet breadth and food plant type were not different. These results partly confirm the peninsula niche breadth hypothesis, which predicted that Oriental species have a broader niche breadth than Palearctic species.  相似文献   
5.
Indochina Peninsula is the primary centre of diversity of rice and lies partly in the centre of origin of cultivated rice (Oryza sativa) where the wild ancestor (Oryza rufipogon) is still abundant. The wild gene pool is potentially endangered by urbanisation and the expansion of agriculture, and by introgression hybridisation with locally cultivated rice varieties. To determine genetic diversity and structure of the wild rice of the region we genotyped nearly 1000 individuals using 20 microsatellite loci. We found ecological differentiation in 48 populations, distinguishable by their life‐history traits and the country of origin. Geographical divergence was suggested by isolation of the perennial Myanmar populations from those of Cambodia, Laos and Thailand. The annual types would be most likely to have lost genetic variation because of genetic drift and inbreeding. The growing of cultivated and wild rice together, however, gives ample opportunities for hybridisation, which already shows signs of genetic mixing, and will ultimately lead to replacement of the original wild rice gene pool. For conservation we suggest that wild rice should be conserved ex situ in order to prevent introgression from cultivated rice, along with in situ conservation in individual countries for the recurrent evolutionary process through local adaptation, but with sufficient isolation from cultivated rice fields to preserve genetic integrity of the wild populations.  相似文献   
6.
7.
This study demonstrates for the first time the presence of marine‐associated mites in the Andaman Sea and Strait of Malacca and reveals a relatively high diversity of these taxa with six species from two different families: Selenoribatidae and Fortuyniidae. Indopacifica, a new genus of Selenoribatidae, is described from Thailand and Malaysia, with two new species, Indopacifica pantai n. sp. and Indopacifica parva n. sp. The genus is characterized by the unique combination of following characters: lacking lamellar ridges, incomplete dorsosejugal suture, fourteen pairs of notogastral setae, and presence of epimeral foveae. A phylogenetic reconstruction based on 18S ribosomal RNA sequences clearly confirms the distinctness of the new genus Indopacifica and places it close to the genus Rhizophobates. The lack of molecular genetic data of possible relatives impedes a clear assessment, and hence, we emphasize the need for further combined approaches using morphological and molecular genetic sequence data. All species show wide distribution areas within this geographic region suggesting that these taxa are good dispersers despite their minute size and wingless body. Molecular genetic data demonstrate recent gene flow between far distant populations of I. pantai n. sp. from the coasts of Thailand and two islands of Malaysia and hence confirm this assumption. The seasonally changing surface currents within this geographic area may favor hydrochorous dispersal and hence genetic exchange. Nevertheless, morphometric data show a slight trend to morphological divergence among the studied populations, whereas this variation is suggested to be a result of genetic drift but also of habitat differences in one population of Alismobates pseudoreticulatus.  相似文献   
8.
This study focuses on plant species richness, taxonomic diversity, and endemism of the Sinai peninsula as a whole and Saint Catherine area in particular. Beta diversity was also measured using T to represent the biotic change between different landforms in the St. Catherine area. The peninsula supports about 1285 species including the infraspecific taxa of which about 800 species (also including the infraspecific taxa) are recorded in the southern Sinai south of El-Tih Desert. The present study reveals that southern Sinai is more diverse as compared with the Sinai peninsula as a whole. Southern Sinai also supports more than the expected numbers of rare and very rare species (about 62%) and about 4.3% endemic species. Beta diversity between different landforms in the St. Catherine area reflect a large biotic change between slopes and terraces on the one hand and between terraces and ridges on the other. Finally, the study recommends appropriate management of the peninsula and more research for the management requirements of the numerous endemic and rare species in the Sinai peninsula.  相似文献   
9.
The peninsula effect – a decrease in species richness from the base to the tip of a peninsula – has been tested for a diverse range of taxa at continental and regional scales. We investigated the peninsula effect at a local scale by examining bird species occurrence in riparian strips (peninsulas) of native eucalypt forest within a radiata pine plantation in the Tumut region, south-eastern Australia. Peninsulas were elongated but 'blind' extensions of a core area of native eucalypt forest. Birds were surveyed by the area search method, within 1.0-ha quadrats established along peninsulas ( n =14), in October and November 2002. Data were analysed using generalized linear mixed models. A significant decrease in bird species richness from the base towards the tip of the peninsulas was observed. The proportion of large bird species recorded per quadrat showed a significant decrease from the base towards the tip of the peninsulas. This pattern was not observed for small birds. Several species were more abundant at the base of the peninsulas than away from the core area of eucalypt forest. The peninsula effect can occur locally in landscape mosaics. Factors leading to the observed patterns of species occurrence may be distinct from those proposed in investigations of the peninsula effect with a biogeographical (macroscale) context. In our microscale study, foraging incursions of individual birds from the core area of native forest through peninsulas were a major factor giving rise to higher bird species richness in the more basal portions of peninsulas.  相似文献   
10.
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