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1.
Butterflies were studied, at the species level, in 47 mountain meadows in a 1.5 × 1.6 km study area in the Picos de Europa National Park, Spain. Butterfly transects were carried out on nine occasions in June and July 2004 and the summed data used in binary logistic and stepwise multiple regression analyses using 28 biotic and abiotic parameters. Models were created for 37 species in total: 24 using logistic regression and 24 with multiple regression; models from both approaches were obtained for 11 species. Abiotic factors dominated many analyses with factors such as proximity to water, aspect and altitude being prominent. Abiotic factors may reflect acceptable minimum conditions for presence of a species and interact with biotic factors to determine habitat quality. Classification of the meadows as either under hay or summer grazing management, or ??winter grazing or abandoned?? was not particularly revealing probably due to inherent variability in management intensity within meadows and degree of abandonment. Features that reflected management influences, lack of management, disturbance, and sward condition featured in many analyses. Whilst many meadows are still actively managed, features that can be related to abandonment are evident for many species. The early stages of relaxation of management intensity can be positive for butterflies, but if management is not restored losses are likely as succession proceeds. The implications of this are briefly discussed.  相似文献   

2.
Semi-natural grasslands resulting from traditional land use practices (mowing and grazing) are severely endangered throughout Europe due to the intensification of agriculture. The ecological impact of mowing and grazing on grassland butterflies was studied in eight mown meadows and eight grazed pastures under traditional animal husbandry in NW Russia and adjacent Finland. Transect count data over 3 years (1997–1999) covered a total of 48 species and 5742 individuals. The butterfly fauna was rather similar under both management forms; species richness, diversity and total abundance did not differ significantly between meadows and pastures, yet meadows were preferred by more species. In both groups, the most abundant species were Aphantopus hyperantus, Pieris napi and Thymelicus lineola. Of 37 species observed as a minimum of five individuals, Polyommatus amandus, Ochlodes sylvanus and A. hyperantus showed a significant preference for mowing management. According to the ordination, butterfly communities were affected more by the origin and age of the grassland than the present management method. Landscape factors (meadow or pasture surrounded by forests or open environments), the abundance of nectar plants and the intensity of tilling were the most important factors differentiating older grasslands from the younger ones evolved from old Finnish hay fields cultivated prior to the 1940s.  相似文献   

3.
In 2004 and 2005, we investigated the distribution of the Glanville fritillary butterfly (Melitaea cinxia) and its host plant in the Tianshan Mountains of China, in order to clarify its habitat utilization. Female butterflies were almost captured on dry meadows on slopes, where plenty of host plant (Veronica spicata) is distributed. Although there are host plants on meadows at higher altitude (>2,050 m), no butterfly was found there. Among the meadows with host plants, a patch of dry meadow (newly-found meadow) was considered as a natal site because of the high density and freshness of butterflies. Unlike females, male butterflies were almost captured in valleys, where there are no host plants and fewer nectar plants. It might be related to specific mating system of M. cinxia in the study site, or specific environmental factors. Thus valleys are important habitat for males. Although the status of M. cinxia is yet unknown in China, we give some suggestions for conservation based on this study. First, dry meadows with host plants are the essential component for persistence of M. cinxia, among which the specific sites with more favourable conditions, such as natal site, are most important. Second, as a site with adult resource requirement, valleys should be included as part of the habitat of the butterfly. Finally, meadows at higher altitude are not utilized at present but they are potential habitats which need to be maintained for any shifts in altitudinal range in response to global warming in the future. Hence, the trade-off of present cost and future benefit should be taken into account when formulating a conservation strategy for M. cinxia in the Tianshan Mountains of China.  相似文献   

4.
During recent decades, concern about the loss of biodiversity on agricultural land has increased, and semi‐natural grasslands have been highlighted as critical habitats. Temperate European agricultural landscapes require distinct and appropriate management to prevent further impoverishment of the flora and fauna. This is especially urgent for pollinating insects that provide important ecosystem services. Our aim was to examine how species richness of three important groups of pollinating insects; solitary bees, butterflies and burnet moths are related to different farm characteristics, and if there are any differences between these three groups. A further aim was to test if red‐listed species are related to any farm characteristics. Species richness of solitary bees, butterflies and burnets was measured on all semi‐natural grasslands at 16 farms in a forest‐dominated area of 50 km2 in southern Sweden, using systematic transect walks in April to September 2003 (only butterflies and burnets) and 2005. Species richness of solitary bees and butterflies was intercorrelated, both before and after controlling for the area of semi‐natural grassland. Species richness of solitary bees increased with the area of semi‐natural grassland. After controlling for the effect of the area of semi‐natural grassland species richness was strongly positively related with the density of the plant Knautia arvensis and negatively related with the proportion of grazed grassland. The results were similar for solitary bees and butterflies. The number of red‐listed solitary bees was positively related to the proportion of meadows with late harvest (after mid‐July) and decreased with increased farm isolation. The number of burnet species (all red‐listed) was positively related to vegetation height, flower density and the proportion of meadows with late harvest on a farm. Areas with a high density of K. arvensis and with traditional hay‐meadow with late harvest present, harbour most species. Promoting traditional hay‐meadows, late extensive grazing and the herb K. arvensis, people managing agricultural biodiversity can encompass high species richness of pollinating insects and support red‐listed species. Further, we suggest that the density of K. arvensis at a farm can be used as a biodiversity indicator, at least for pollinating insects.  相似文献   

5.
A chronosequence, representing a successional series, was used for the comparison of a hay meadow site managed in an old traditional way for at least a hundred years, and hay meadow sites abandoned for about 10, 20 and 30 years, respectively. Old traditional management included grazing early and late in the growing season, mowing in August and light or no fertilizing. The tree cover was the most important factor deciding the composition of vegetation. Time since abandonment was not completely correlated to tree cover, as some plots had a dense canopy and others were situated in the open. The total species number decreased with number of years since abandonment in plots > 0.001 m2and <100 m2. The highest species number in 1 m2 plots was recorded in the managed site, with 38 species of phanerogams. Fourtyeight % of the indicators of traditional management present in the managed site was recorded in the site which had been abandoned for 30 years. Frequency — log area curves made it possible to group species according to persistence in the sward. As a result, a group of functional indicators of rare hay meadows in the region was distinguished.  相似文献   

6.
Species pool theory claims that diaspore and microsite availability limit species richness in plant communities. Wet meadows (Calthion) and litter meadows (Molinion, Caricion davallianae) belonging to the most species-rich meadows in the foothills of the Alps have suffered from a strong decrease since the 1970s. Restoration efforts including nutrient impoverishment and rewetting management after drainage and fertilization did not result in the re-establishment of the former species richness although the abiotic filter would have been appropriate for the re-colonization of many locally extinct species. In our experiment at four sites in the largest fen of Southwest-Germany we tested if the restoration success was seed- and gap-limited. We applied sowing and hay spreading (hay seed) as treatments to make seeds available and harrowing to increase gap availability. Sowing seeds or hay seed of species of the former meadow types increased species richness immediately. The proportion of re-established species was higher when additional harrowing was applied. Species richness could be increased not only in vascular plants but also in bryophytes when hay spreading was applied. The strongest re-development towards the target communities (defined through the abiotic filter and the species richness before drainage and fertilization) took place on those sites where hay spreading and harrowing were applied. Sowing seeds and hay seed were traditional techniques to establish e.g. litter meadows, both techniques have been applied for centuries. Even harrowing was described as early as the 19th century to increase the chance of establishing certain species. Therefore, the “application of the knowledge coming from the species pool theory” (although not named during this time) has been common practice since at least the 19th century.  相似文献   

7.
Conservation status of hay meadows highly depends on their management. The main goal of this study was to assess the efficiency of different mowing regimes in maintenance of plant species richness and diversity of mesic hay meadows. The field experiment was carried out on a species rich, mesic hay meadow in Western Hungary. We evaluated the effects of four alternative types of management on the plant community after 7 years of continuous treatment: (1) mowing twice a year, typical traditional management, (2) mowing once a year in May, most practised currently by local farmers, (3) mowing once a year in September, often proposed for conservation management and (4) abandonment of mowing. Traditional mowing resulted in significantly higher number and higher diversity of vascular plant species than other mowing regimes. Mowing twice a year was the only efficient way to control the spread of the invasive Solidago gigantea, and mowing in September was more successful in it than mowing in May. We conclude that the traditional mowing regime is the most suitable to maintain botanical diversity of mesic hay meadows; however, other regimes should also be considered if certain priority species are targeted by conservation.  相似文献   

8.
Abstract. A local seed mixture from plants growing in a species‐rich, traditionally managed hay meadow site at Varaldsoy, Hardanger, western Norway, where many endangered hay meadow species of the region are growing, was sown in a newly harrowed experimental field 1 km from the source meadow in order to increase the habitat area for the endangered species. Of 25 endangered species recorded in the source meadow, only one (Holcus lanatus) was present in the target meadow. After sowing, 16 of the endangered species in addition to Holcus lanatus were recorded in the new site. Six species were only present in sown plots and seven others were more frequent there, while three species might have arrived by chance or originated from the seed bank. Replacing the traditional management regime, including one late cut and grazing in spring and in autumn, with three cutting times and the creation of gaps in the sward, resulted in a higher number of endangered species in plots which were only cut, possibly because the grazing was too intensive in the small enclosures.  相似文献   

9.
Butterfly, spider, and plant species richness and diversity were investigated in five different land-use types in Sardinia. In 16 one-hectare plots we measured a set of 15 environmental variables to detect the most important factors determining patterns of variation in species richness, particularly endemicity. The studied land-use types encompassed homogeneous and heterogeneous shrublands, shrublands with tree-overstorey, Quercus forest and agricultural land. A total of 30 butterfly species, among which 10 endemics, and 50 spider (morpho)species, were recorded. Butterfly and spider community composition differed according to land-use type. The main environmental factors determining diversity patterns in butterflies were the presence of flowers and trees. Spiders reacted mainly to habitat heterogeneity and land-use type. Traditional land-use did not have adverse effects on the diversity of butterflies, spiders, or plants. The number of endemic butterfly species per treatment increased with total species richness and altitude. Butterfly and spider richness did not co-vary across the five land-use types. Butterflies were, however, positively associated with plant species richness and elevation, whereas spiders were not. Conclusively, butterflies did not appear to be good indicators for spider diversity and species richness at the studied sites.  相似文献   

10.
Abstract. Sheep grazing was investigated as an alternative to traditional management of meadows in the Krkono?e Mts. Until the second World War these meadows were mown in mid‐summer and grazed by cattle for the rest of the season. Subsequent abandonment of the meadows has resulted in decreasing species richness. Degradation phases of the former communities have been replacing the original species‐rich vegetation. Significant changes were apparent six years after the introduction of sheep grazing. In grazed plots the proportion of dominant herbs (Polygonum bistorta and Hypericum maculatum) decreased and grasses (Deschampsia cespitosa, Festuca rubra, Agrostis capillaris, Anthoxanthum alpinum) increased. The increase in grasses was positively correlated with an increase in several herbs. The proportion of some herbs increased despite being selectively grazed (Adenostyles alliariae, Melandrium rubrum, Veratrum lobelianum). Any losses caused by grazing of mature plants were probably compensated by successful seedling establishment. Cessation of grazing resulted in significant changes in vegetation within three years. The cover of nitrophilous tall herbs and grasses (e.g. Rumex alpestris, Holcus mollis, Deschampsia cespitosa, Geranium sylvaticum) increased in the abandoned plots. In the plots grazed for nine years cover of species‐rich mountain meadow species increased (e.g. fine‐leaved grasses, Campanula bohemica, Potentilla aurea, Viola lutea, Silene vulgaris). The main conservation risk is the expansion of a competitive species with low palatability, Deschampsia cespitosa. This species can be suppressed by a combination of grazing and mowing. In order for grazing to be effective, the number of sheep should be proportional to meadow production. This may be difficult to maintain as production is variable and is impossible to predict at the beginning of a growing season. A large part of the biomass may thus remain intact in some years. Negative effects of grazing may be, at least partly, eliminated by a combination of cutting and grazing.  相似文献   

11.
Early succession of butterfly and plant communities on set-aside fields   总被引:9,自引:0,他引:9  
 Hypotheses on secondary succession of butterfly and plant communities were tested using naturally developed 1- to 4-year-old set-aside fields (n = 16), sown fields (n = 8) and old meadows (n = 4) in 1992 in South Germany. Pioneer successional fields (1st and 2nd year of succession, dominated by annuals) and early successional fields (3rd and 4th year of succession where perennials, especially grasses became dominant) had fewer plant species than mid-successional fields (old meadows). In contrast to established hypotheses, mean number of plant species decreased from 1- to 4-year-old set-aside fields. Species richness of butterfly communities did not change during the first four years of succession, but species composition changed greatly. Pioneer successional fields were characterized by (1) specialized butterflies depending on annual pioneer foodplants (e.g. Issoria lathonia), and (2) species preferring the pioneer successions despite their host plants being more abundant on early and mid-successional fields (e.g. Papilio machaon). The variability in butterfly species richness was best explained by flower abundance which was closely correlated with plant species richness. Species whose abundance was correlated with habitat connectivity were significantly smaller than species which correlated with flower abundance. Numbers of caterpillar species were correlated with numbers of adult butterfly species. Life-history features of butterflies changed significantly from pioneer to early and mid-successional fields. We found decreasing body size and migrational ability, decreasing numbers of species hibernating as imago, decreasing numbers of generations and increasing larval stage duration with age of succession, but, contrary to expectation, host plant specialization, numbers of egg-cluster laying species and egg diameter did not change with successional age. Received 18 September 1995 / Accepted: 17 July 1996  相似文献   

12.
Abstract. The biodiversity of species‐rich semi‐natural meadows is declining across Europe due to ceased management. In this study we aimed to find out how successfully the local species richness of an overgrown semi‐natural mesic meadow could be restored by sheep grazing after a long period of abandonment. The cover of vascular plant species in grazed plots and ungrazed exclosures was studied for five years and the responses of different functional plant groups were followed (herbs vs grasses, tall vs short species, species differing in flowering time, species representing different Grime's CSR strategies and species indicative of rich vs poor soil). Grazing increased species number by nearly 30%. On grazed plots the litter cover practically disappeared, favouring small herbs such as Rhinanthus minor, Ranunculus acris, Trifolium pratense and the grass Agrostis capillaris. Grazing decreased the cover of the late flowering tall herb Epilobium angustifolium but had no effect on the abundance of the early flowering tall herbs Anthriscus sylvestris or Geranium sylvaticum. We suggest that to succeed in restoration it is useful to determine the responses of different functional plant groups to grazing. Grassland managers need this information to optimize the methods and timing of management used in restoration. Additional management practices, such as mowing, may be needed in mesic meadows to decrease the dominance of tall species. The availability of propagules seemed to restrict further increase of species richness in our study area.  相似文献   

13.
Aggressive growth by legumes may restrict the diversity of species-rich meadows recreated on sites restored after mineral extraction. We investigated the ability of mineral nitrogen (N) applications and spring grazing to control the legume component of such meadows. The use of N suppressed Trifolium repens but had no effect on other legume species or on the species richness, diversity, or equitability of the meadow community. Spring grazing significantly reduced the yield from the legume component of the meadow. This was accompanied by an increase in the equitability index of the community, suggesting that the aggressive nature of the legumes had been checked. Spring grazing may therefore provide a means of controlling aggressive legume growth and may maintain the diversity of species-rich meadows established on restored sites.  相似文献   

14.
How flooding regimes shape temperate-zone butterfly communities has received little attention. At the river Danube in eastern Austria, a levee has largely interrupted natural river dynamics since the late nineteenth century. Only a fraction of the floodplain area still experiences annual summer inundations after snow-melt in the Alps. We surveyed meadow butterfly communities on either side of the levee in a year with an unusually strong flood (2013), and in a season with a weak flood typical for the region (2012). Altogether we observed 67 butterfly species. Butterfly abundance and species richness were lower on meadows with stronger flood impact, but differences were modest. In contrast, species composition differed prominently relative to flooding regime and nectar availability. Grass-feeding species tended to be rarer on flooded meadows, while Brassicaceae-feeding species were more prevalent on nutrient-rich flood-prone meadows. Highly dispersive butterflies made up a larger share on flooded meadows, whereas highly philopatric species were relatively more common at sites with little or no inundation. These results indicate that summer inundations at the river Danube act as filters for the local species composition of butterflies on floodplain meadows. Local resource availability and the differential potential of species to re-colonize meadows after catastrophic floods are likely drivers of these differences. Effects of inundations were not consistently stronger in a year of a catastrophic flood than in a normal season. Butterfly communities on non-flooded meadows had a higher regional conservation value.  相似文献   

15.
The objective of this study was to compare butterfly abundances and diversity between wildflower strips and extensively used meadows to identify which butterfly species can be supported by establishing wildflower strips. Butterflies were recorded along transects during one season in twenty-five sown wildflower strips and eleven extensively used meadows in a Swiss lowland agricultural landscape (600 ha). In total 1,669 butterflies of 25 species were observed (25 in the strips, 18 in meadows). This can be related to 38 species recorded in the region (lowland part of Kanton Fribourg) within the Swiss Biodiversity Monitoring Programme. In wildflower strips the number of butterflies per transect meter was significantly higher than in the meadows, but there was no significant difference in species richness. Butterfly communities, though, were quite different between the two habitat types. Habitat type, abundances of flowering plants and presence of forest within 50 m were identified as factors influencing butterfly species richness. Butterfly abundances were affected by habitat type and abundance of flowering plants. In wildflower strips, 65% of all flower visits by butterflies were observed on Origanum. It can be concluded that sown wildflower strips can support a substantial part of a regions species pool. This is mostly true for common species, but can apply to rare species when, for example, larval food plant requirements are met.  相似文献   

16.
新疆东部天山蝶类多样性及其垂直分布   总被引:5,自引:0,他引:5  
张鑫  胡红英  吕昭智 《生态学报》2013,33(17):5329-5338
2006-2008年研究了新疆东部天山蝶类多样性和垂直分布.结果表明:研究区域内共记录蝴蝶7科43属63种,占新疆已记录蝶类种数的24.80%,区系组成主要是古北种,占73%;其次是广布种,占27%,没有发现东洋种.其中蛱蝶科的物种数最多,为11属19种,蚬蝶科的物种数最少,只有1属1种.按海拔将生境分为5个垂直自然带,包括低山灌木草原带、山地森林草原带、亚高山草甸带、高山草甸带、垫状植被带.蝶类物种数和个体数排序为亚高山草甸带>山地森林草原带>低山灌木草原带>高山草甸带>垫状植被带.采用Shannon-Wiener指数和G-F指数对蝶类物种和科、属的多样性进行了分析评价,结果显示亚高山草甸带的蝶类多样性最为丰富,其次是山地森林草原带和低山灌木草原带,而高山草甸带和垫状植被带的蝶类多样性相对较低,物种和科、属多样性分析结果均一致.蝶类垂直分布明显,物种数和个体数随海拔变化的趋势类似,均为先增加后下降.蝶类区系成分随着海拔升高发生改变,广布种的比例逐渐降低,高山草甸带和垫状植被带只有古北种分布.研究结果显示,生境改变对蝴蝶群落影响明显,保护生境是保护蝴蝶生存的最主要措施.  相似文献   

17.
Habitat type and quality are recognised as important local determinants of species richness, but other processes operating at the landscape scale can also affect diversity patterns. The evidence regarding the relative importance of landscape context on vascular plants is diverse, and little is known about the effects of this complex factor in Alpine environments. Hence, the primary purpose of the study was to elucidate the relative effects of the determinants of plant species richness by decomposing the variation into local and landscape components. We sampled 99 hay meadows in the Italian Alps, and recorded 14 explanatory variables ascribed to three sets: two sets of local variables, meadow management and abiotic environment, and a set of landscape variables. Plant diversity was affected primarily by local determinants. Species richness tended to increase in less fertilised meadows, confirming the detrimental effect of intensive meadow management on plant diversity. Site conditions such as steep slopes also enhanced plant species richness, showing a most pronounced positive effect in meadows that were cut less frequently. As to the landscape determinants, a high proportion of urban elements affected species richness negatively probably due to further eutrophication. In contrast, an increased length of meadow edges had a positive effect, particularly in meadows located on shallow soils. Partitioning analyses revealed that the three sets of variables showed relatively large shared effects with each other (over half of the total variation explained). In conclusion, the composition of the surrounding landscape had a lower impact on vascular plant species richness than did meadow management and local abiotic environment.  相似文献   

18.
Questions: Which factors influence the persistence of vascular grassland plants in long‐abandoned (at least 50 yr) arable fields and meadows? What might be the implications of current levels of species richness on abandoned arable fields and meadows for future restoration? Location: Forested highlands of Kilsbergen, south central Sweden. Methods: The abundance of all vascular plant species was investigated in three habitat types: former arable fields, hay meadows and outlands (pastures) at 27 farms, abandoned for either approximately 50 yr or 90 yr. Time since abandonment, tree cover, soil depth, degree of soil podsol development, size of the infield area and two measures of connectivity were used as predictors for species richness and species composition. Results: Former outland had denser tree cover, fewer species and fewer grassland species than former arable fields and hay meadows, irrespective of time since abandonment. Former hay meadows and arable fields with a longer time since abandonment were less rich in species, more wooded and had greater podsolization than meadows and fields abandoned at a later stage. Species richness was higher in hay meadows and arable fields at farms with larger infield area and deeper soils compared with farms with smaller infield area and shallower soils. The greatest richness of species and most open habitat were former arable fields at larger farms abandoned 50 yr before the study. Former arable fields had the highest number of grassland species. Conclusion: After 50 yr of abandonment, former arable fields were the most important remnant habitats for grassland species and may be a more promising target for restoration than formerly managed grasslands.  相似文献   

19.

Aims

Once widely used across Europe, grazing of hay meadows is now a rare agricultural practice that is mainly applied in rural regions with maintained traditional agriculture. In this review, we examine the knowledge on grazing hay meadows in the Carpathian Mountains, including its historical distribution, implementation and timing, potential impacts on grassland productivity and biodiversity, and implications for grassland conservation and restoration.

Location

The Carpathian Mountains (43.8–50.1°N, 16.9–27.1°E).

Methods

We conducted a literature review including biological, ecological, agricultural, ethnological, and historical sources.

Results and Conclusions

In each of the seven farming systems that existed in parallel in the Carpathian Mountains before agricultural intensification, grazing of hay meadows was applied regularly. Spring, autumn, and occasionally summer grazing, along with corralling and manuring of hay meadows, were integral parts of these systems, adapted to the seasonal movement of dairy farms across various agroecosystems. The data reviewed provide insight into the role of animals in hay meadow management, as well as how the breakdown of these historical farming systems is impacting local biodiversity, the economy, and the community. According to the literature sources, grazing hay meadows has numerous positive impacts on grassland biodiversity, including suppressing fast-growing competitors, reducing the accumulation of litter, increasing the availability of germination gaps, dispersing seeds through zoochory, supporting ground-nesting birds through later mowing, and promoting the regeneration of plants from seeds. From this perspective, the combination of mowing and grazing can be considered a promising tool in current grassland conservation and restoration efforts.  相似文献   

20.
A survey was conducted on the species composition, richness and abundance of Papilionoidea (excluding Lycaenidae) butterfly fauna in habitats with various degrees of disturbance and altitudes in tropical forests at Tam Dao National Park, northern Vietnam in 2001. The transect method was used to collect data in the survey. Six transects representing different habitat types at two sites, one site located at a low elevation of 200–250 m a.s.l., and the other located at a high elevation of 950–1000 m a.s.l., were chosen: three transects for each site, with a length of 500 m for each transect. A total of 3594 individuals of 127 species in 240 sets of data were recorded from various habitats. The differences in butterfly composition, species richness, abundance and diversity in different habitat types and altitudes were analyzed. The results showed significant differences of butterfly diversity among the different habitat types and between the low and high altitude sites. The butterfly diversity, species richness and species abundance in the low elevation habitats were higher than in the high elevation habitats. The highest diversity of butterflies occurred in the mixed habitats of agriculture, scrub and clearing lands of high disturbance. However, butterflies most important for conservation are associated with undisturbed or moderately disturbed forests only.  相似文献   

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