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1.
The Euxinian and the Hyrcanian floristic province are analysed in respect to their trees and shrubs. These provinces mark the southern limit of the Euro-Siberian Region in SW. Asia. Mesophyllic forests dominate; they are deciduous, but there is a substantial component of evergreen shrubs in the understorey. Characteristics species frequently have a relic nature. Species lists and some exemplary distribution maps are presented for the Euxinian and the Hyrcanian element, both with endemic and more wide-spread species, including the characteristic Euxine-Hyrcanian group.  相似文献   
2.
The mesic Caspian (Hyrcanian) forest and ecotone communities provide a marked contrast to the arid and semiarid landscapes associated with most of the territory of Iran. To date, the ecological characteristics of these habitats, threatened and of conservation importance, have been little studied. Accordingly, ecological profiles of some important plant species of these communities have been assessed along two altitudinal gradients (300–2300 m a.s.l.). Vegetation and soils were sampled every 100 m in elevation, with the data subsequently analyzed using TWINSPAN and corrected frequency (CF) analyses. Relationships between soil variables (subdivided into three classes, the lowest, the middle and the upper third of all values) and herbaceous and shrub species (presence/absence data) were analyzed by the polythetic divisive classification method. 379 plant species and eleven soil variables – N, P, K, CaCO3, EC, pH, organic matter, C/N ratio and percentage of sand, clay and silt – were considered. The ecological profile method was used to evaluate the affinity and significance of associations between the probability of species’ occurrence and topsoil characteristics found by the polythetic method. Five vegetation groups were identified: two groups, with Acer campestre and Quercus macranthera in the tree layer and Veronica mazanderanae and Phuopsis stylosa as herbs, were restricted to forest-steppe ecotones and the upper mountain areas. Three groups, with Acer velutinum, Ruscus hyrcanus, Carpinus betulus, Danae racemosa, Fagus orientalis and Aruncus vulgaris as indicator species, occurred in the forest itself. Of the 42 plant species assessed as being of particular importance, 13 had significant relationships with eight soil factors. Thus, certain species, including endemic plant species of restricted distribution and conservation importance, can be used as indicators of particular soil conditions in the Hyrcanian forest area.  相似文献   
3.
New systematic conservation approaches have high potential in evaluation of different conservation scenarios and can be used as decision support tools for managers and planners with multiple goals. The present study focused on two major issues in conservation planning including socioeconomic costs and zoning procedure. The goal was to prioritize and identify representative areas for bird conservation, while minimizing the economic cost for the silvicultural sector and resolve conflicts with recreational activities. The study was conducted in forest areas of Golestan Province as part of Hyrcanian mixed forests, located along the southern coasts of the Caspian Sea and northern slopes of the Alborz Mountains, northern Iran. We used systematic conservation software Marxan with Zones to select candidate areas for conservation. Two types of conservation networks were defined, one with high and partial protection zones and the other with high protection zones only. We focused on four conservation scenarios varying in targets, costs, and multiple zones. The results showed that incorporation of socioeconomic costs significantly decreases the potential impacts on the silvicultural and recreational sectors without significant change in the area of protection zones. Furthermore, we found that design of multiple zone conservation areas facilitates evaluation of a wider range of conservation scenarios that can reduce potential socioeconomic impacts on other interests.  相似文献   
4.
The vascular flora of the Siahrud e Rudbar protected area was investigated in the years 2007 and 2008. It is a sylvatic area in the Guilan province with a total area of approximately 28289 hectares. A total of 711 plant specimens were collected and 616 species, subspecies, and varieties, belonging to 373 genera and 101 families were identified. Of these, 14 species (23%) are endemic to Iran. The documented flora exhibited many typically Hyrcanian species, including Hyrcanian endemics. The global phytogeographical affinities of the species were as follows: Euro Siberian 212%, Iran Turanian & Euro Siberian 168%, Pluriregional 117%, Iran Turanian 106%, and Cosmopolite 55%.  相似文献   
5.
Addressing widespread livestock losses to carnivores requires information on which livestock categories are preferentially selected. We analyzed an individual‐based database of cattle grazing in forest (n = 932) and having been killed (n = 70) by leopards (Panthera pardus) in the Hyrcanian forest, Iran. We calculated Jacobs’ selectivity index for cattle age, sex, and coloration across four scales: the study area as a whole, three sites, nine villages, and 60 cattle owners. Naturally colored cattle were significantly preferred by leopards at all scales in comparison with black and black‐and‐white cattle, and there was also a preference for males and juveniles at the study area level. More research is needed to see whether cattle losses would decrease if the share of naturally colored individuals in local holdings was reduced and males and juveniles had limited access to forest. We conclude that phenotypic and biologic characteristics of livestock can affect depredation and appeal for more research in this direction, particularly within the predator–prey framework.  相似文献   
6.
Recent epidemics of box (boxwood) blight caused by the fungus Calonectria pseudonaviculata in Hyrcanian forests led to the search for eco-friendly fungicides. Essential oils (EOs) of medicinal plants undoubtedly have been highlighted as a new therapeutic approach. In this study, EOs from Cuminum cyminum, Lavandula angustifolia, Thymus daenensis, Trachyspermum copticum and Hyssopus officinalis were evaluated for their inhibitory activities against C. pseudonaviculata Cy-08 in vitro. Quantitative and qualitative composition variations of the EOs were also analysed by GC–MS. Based on the high inhibitory efficacy and low related EC50, MFC and MIC values, T. copticum, L. angustifolia and Th. daenensis EOs can be mentioned as those providing extraordinary efficacy against Cy-08, respectively. Major chemical components of T. copticum, L. angustifolia and Th. daenensis EOs were thymol, linalyl acetate and thymol, respectively. Thymol and linalyl acetate may be the most effective compounds against C. pseudonaviculata.  相似文献   
7.
The Hyrcanian forest of northern Iran is considered one of the potential centres for the evolution and domestication of the genus Malus (Rosaceae). However, the biogeography, phylogenetic position, and taxonomic status of the Hyrcanian wild apples have never been evaluated. In our study, the nucleotide sequences of the internal transcribed spacer (ITS) and the trnH-psbA intergenic spacer region from 14 natural populations were analysed. Phylogenetic analysis based on the ITS and the Maximum-likelihood (ML) tree showed that all Hyrcanian samples were closely related to M. orientalis and M. asiatica and can be placed within section Malus and series Malus. Furthermore, based on a comparison of ITS2 secondary structures, the Hyrcanian samples were identical to M. orientalis and M. sieversii. Biogeographic scenarios constructed using Statistical Dispersal-Vicariance Analysis (S-DIVA) and the Bayesian Binary Method (BBM) indicated that the ancestor of Malus originated during the Eocene, ~53 million years ago (Ma), and that China played a vital role in the expansion of the range of the genus. The members of Malus colonized the Hyrcanian region from China during the Miocene, ~22-10?Ma.  相似文献   
8.
We hypothesized that associations among plant functional traits may differ within different ecological assemblages and plant communities. Association among plant traits including plant maximum height, seed weight, fruit type, pollination mode, mean leaf area, and leaf type were explored within life forms, plant strategy groups along with lowland and montane forest vegetation. In total, 83 sampling plots of 400 m2 were placed along a 2400 m altitudinal gradient in Hyrcanian forest. Importance‐values of species within vegetation types were used for weighting data and trait associations were explored using categorical principal component analysis. A G‐test and Fisher's exact test of independence were used to retest significance of the correlations. Different paired trait associations (association lines) including height–leaf, height–seed, height–pollination, leaf–seed, seed–fruit and fruit–pollination were observed and their ecological or physiological basis was discussed. Life forms, strategy types and vegetation types differed based on association lines. Some of the well‐known trade‐offs appear by increasing scale from ecological groups to vegetation types in Hyrcanian forest. The observed patterns of trait associations in Hyrcanian forest and several other ecosystems of the world call the generality of previously accepted trait correlations into question.  相似文献   
9.
The west Asian Viola sintenisii W.Becker, described from temperate woodlands of northern Iran and south-western Turkmenistan on the Caspian coast, was long considered a vicariant geographical subspecies of the mainly south European V. alba Besser. The new findings of V. sintenisii in four geographically separated stations in north-eastern Azerbaijan significantly expands its range of distribution. These occurrences are within the range of V. alba ssp. alba . Here the two taxa frequently co-occur but remain distinct and V. sintenisii is therefore justified at species level. It is likely that the two species are also sympatric in the Hyrcanian region, a range previously attributed uniquely to the latter. Viola sintenisii seems to be fairly common in the eastern parts of the Great Caucasus, but there are reasons to suggest that it has there been misinterpreted as V. suavis . The chromosome number of V. sintenisii , 2 n  = 20, is reported here for the first time.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 91–98.  相似文献   
10.
Iran's Hyrcanian forests cover a relatively narrow strip in the northeastern part of the country, and are among the most important and valuable ecosystems inscribed in United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage List. European yew Taxus baccata L. is a Tertiary relict in the region and a long-lived dioecious tree with high ecological and economic importance in the Hyrcanian forests. To study the structure and analysing the survivorship of yew stands, we selected two forest reserves (Gazou and Afratakhteh) with European yew. In the two study areas, we established 165 0.1 ha circular sample plots (75 of the sample plots were in Gazou and 90 sample plots were in Afratakhteh) and measured three characteristics of each tree. The structure of the stands was quantified by means of 1) size distributions by diameter at breast height (DBH), 2) height classes, 3) and stand basal area. Comparison of the diameter distribution by DBH classes in two the forest reserves showed that there was no statistical difference between the two populations. The highest number of yew trees in the Afratakhteh and Gazou populations were in the 12–16 and 18–24 m height classes, respectively. In Gazou, abundance was greatest at 1000 m a.s.l. on mesic exposures and intermediate slopes (40–50%), whereas in Afratakhteh it was found at 1600–1620 m a.s.l. on east-facing areas with 55–65% slopes. Static life tables indicated that the first two age classes have particularily high mortality. Based on these results, we conclude that forest managers should support the regeneration of stands and increase survival rates by applying treatments such as thinning and selective removal of shrubs and saplings of other tree species.  相似文献   
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