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351.
Pasi Laihonen Mia Rönkä Harri Tolvanen Risto Kalliola 《Biodiversity and Conservation》2003,12(1):103-120
To function effectively, the international biodiversity Clearing HouseMechanism (CHM), based on the Convention on Biological Diversity (CBD), needs tobe rooted at the regional and local levels. This article presents an example ofhow stakeholders of regional data and information can be encouraged to formnetworks linked to national biodiversity focal points (NFPs). We pay specialattention to exploiting the geospatial properties of biodiversity data andinformation, and demonstrate how data and information can best be filtered,classified and labelled to facilitate geographically based information retrievalon the Internet. The geocodability of bibliographic reports proved to be poor,indicating an urgent need to reconsider the geographical properties ofbiodiversity information under production. Also, it is useful to utilisenetworking processes with information from fields other than biodiversity wheninitiating the network. Finally, we present and discuss problems of integrityand interoperability of data, and also the process of biodiversity informationproduction from the point of view of general information theory and innovationsoffered by modern information technology. 相似文献
352.
We used electrophoretically identified material to assess the geographical distributions, life cycles and interspecific hybridization
of two sibling species of the Mysis relicta species group (sp. I and sp. II) in the northern Baltic region. In the Gulf of
Finland, sp. I prevails in inshore waters and sp. II in the open sea; the distributions overlap in the outer archipelago zone.
In the Gulf of Bothnia, only sp. II was found in the southern part (Bothnian Sea), whereas the two species coexist throughout
the northerly Bothnian Bay. Both the local and large-scale distributions are salinity-related, but salinity alone does not
explain the differences. The two species exhibit different patterns of geographical variation in their life histories. In
strict sympatry in the north they have identical two-year life cycles with winter breeding. Further south (Gulf of Finland),
sp. I exhibits a predominantly one-year winter-breeding cycle, whereas sp. II breeds throughout the year. The patterns comply
with the concept of a great phenotypic flexibility and environmental control of life history characteristics in the Mysis
relicta group, and make a contrast to the stable life cycle of the congeneric M. mixta. F1 hybrids between the two M. relicta
group species were found at a low frequency (0.6%) in the Bothnian Bay, but not in other areas of sympatry.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
353.
Delayed density-dependent mortality induced by delayed numerical response of predators can drive prey populations to fluctuate in high-amplitude cycles. We studied numerical response of goshawks Accipiter gentilis to varying densities of their main prey (forest grouse) in western Finland during 1979–1996. Occupancy rate of goshawk territories tracked grouse numbers with a two year lag. Occupancy rate of goshawk territories and pooled number of adult and young goshawks correlated negatively with a 1–2 year lag to the chick production of grouse. Goshawk to grouse ratio was negatively related to grouse density. This suggests that goshawk predation on grouse is inversely dependent on grouse density. We conclude that in northern Europe with few alternative preys, goshawk predation might contribute to the generation of multiannual cycles of forest grouse. This should be tested experimentally. 相似文献
354.
Jane Koskimäki Otso Huitu Janne S. Kotiaho Satu Lampila Antero Mäkelä Risto Sulkava Mikko Mönkkönen 《Population Ecology》2014,56(2):341-348
To devise effective conservation actions, it is important to know which factors are associated with the population parameters of a declining population. Using mark–recapture methods, we estimated the annual population size, growth rate and survival probability of an ear-tagged flying squirrel population over a 15-year period in a 4,500 ha study area in western Finland. The species is considered vulnerable, but detailed knowledge concerning population sizes or trends is lacking. The population parameters and changes therein were regressed against habitat availability, an indicator of predation pressure, and mean winter temperature (an indicator of climate change), to reveal potential reasons for trends in the population. The best-fit models suggested the annual growth rate to be below one, and on average it was 0.93 (±0.06; SE) across the 15-year period. The survival probability was about 0.22 (±0.03) for juveniles and 0.50 (±0.03) for adults. The population size of adult flying squirrels decreased from 65 (±11) individuals in 1995 to 29 (±6) individuals in 2009. The number of flying squirrels was associated with the amount of available habitat, but the decline in population size was more rapid than the loss of habitat area. If the current decreasing trend in habitat availability continues, the population might become extinct by the year 2020. To halt the population decline, it is necessary to refrain from clear-cutting mature spruce stands until new suitable habitats develop from the maturation of younger forests. 相似文献
355.
356.
Assessing the vulnerability of European butterflies to climate change using multiple criteria 总被引:1,自引:0,他引:1
Risto K. Heikkinen Miska Luoto Niko Leikola Juha Pöyry Josef Settele Otakar Kudrna Mathieu Marmion Stefan Fronzek Wilfried Thuiller 《Biodiversity and Conservation》2010,19(3):695-723
Vulnerability of 100 European butterfly species to climate change was assessed using 13 different criteria and data on species
distributions, climate, land cover and topography from 1,608 grid squares 30′ × 60′ in size, and species characteristics increasing
the susceptibility to climate change. Four bioclimatic model-based criteria were developed for each species by comparing the
present-day distribution and climatic suitability of the occupied grid cells with projected distribution and suitability in
the future using the HadCM3-A2 climate scenario for 2051–2080. The proportions of disadvantageous land cover types (bare areas,
water, snow and ice, artificial surfaces) and cultivated and managed land in the occupied grid squares and their surroundings
were measured to indicate the amount of unfavourable land cover and dispersal barriers for butterflies, and topographical
heterogeneity to indicate the availability of potential climatic refugia. Vulnerability was also assessed based on species
dispersal ability, geographical localization and habitat specialization. Northern European species appeared to be amongst
the most vulnerable European butterflies. However, there is much species-to-species variation, and species appear to be threatened
due to different combinations of critical characteristics. Inclusion of additional criteria, such as life-history species
characteristics, topography and land cover to complement the bioclimatic model-based species vulnerability measures can significantly
deepen the assessments of species susceptibility to climate change. 相似文献
357.
Heidi K. Mod Risto K. Heikkinen Peter C. le Roux Henry Väre Miska Luoto 《Polar Biology》2016,39(4):649-657
Biotic interactions may strongly affect the distribution of individual species and the resulting patterns of species richness. However, the impacts can vary depending on the species or taxa examined, suggesting that the influences of interactions on species distributions and diversity are not always straightforward and can be taxon-contingent. The aim of this study was therefore to examine how the importance of biotic interactions varies within a community. We incorporated three biotic predictors (cover of the dominant vascular species) into two correlative species richness modelling frameworks to predict spatial variation in the number of vascular plants, bryophytes and lichens in arctic–alpine Fennoscandia, in N Europe. In addition, predictions based on single-species distribution models were used to determine the nature of the impact (negative vs. positive outcome) of the three dominant species on individual vascular plant, bryophyte and lichen species. Our results suggest that biotic variables can be as important as abiotic variables, but their relative contributions in explaining the richness of sub-dominant species vary among dominant species, species group and the modelling framework implemented. Similarly, the impacts of biotic interactions on individual species varied among the three species groups and dominant species, with the observed patterns partly reflecting species’ biogeographic range. Our study provides additional support for the importance of biotic interactions in modifying arctic–alpine biodiversity patterns and highlights that the impacts of interactions are not constant across taxa or biotic drivers. The influence of biotic interactions, including the taxon contingency and range-based impacts, should therefore be accounted for when developing biodiversity forecasts. 相似文献
358.
Using data from 46 sites in southern Finland and ordination methods, we examined plant-environment relationships in boreal
mesic semi-natural grasslands at two spatial scales (grain sizes), using plots of 0.25 ha and 1 × 1 m. We applied the variation
partitioning approach to determine the pure fractions of environmental variable groups and their joint effects on plant species
compositional variation in the studied grasslands. The variables related to land-use intensity and high nutrient level (especially
phosphorus) had a major role in explaining the species composition at both scales, although soil heterogeneity and habitat
characteristics also accounted for a notable amount of the species compositional variation at the 0.25 ha grain size. At the
1 × 1 m grain size, the majority of the species compositional variation was related to the “pure” spatial differences between
the studied grasslands (i.e. the site identity (dummy 0/1) variable), whereas the impacts of within-site variation of local
environmental factors were considerably smaller. High nutrient levels and variables related to low land-use intensity, e.g.
litter accumulation, were also significantly correlated with floristic variation at the 1 × 1 m grain size. Rare and declining
grassland species are associated with low-nutrient grassland sites and patches. The main recommendation for the management
planning of boreal semi-natural grasslands is that the first restoration attempts should be targeted to areas where nutrient
levels, particularly that of phosphorus, are relatively low. Soil properties and plant species composition can provide useful
guidelines for defining the correct management procedures for different sites. 相似文献
359.