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1.
Preservation of woodland key habitats has become an integral part of biodiversity-oriented forest management in northern Europe. In Finland, brook-side spruce forests constitute the most important key-habitat type in terms of total area and timber volume. Our aim was to compare polypore diversity and the occurrence of red-listed species between brook-side key habitats and comparable sites of managed forest as controls. Furthermore, we assessed the importance of stand structural features to polypore communities, and contrasted regions with different land-use history. Altogether 69 key habitats and 70 controls were inventoried in four regions across southern Finland. A total of 28,023 surveyed dead-wood units had 3,307 occurrences of 114 species of which 25 species were red-listed. Key habitats hosted on average 28% (about two species) more polypore species (mainly deciduous-specialists) than controls because of a larger average volume of dead wood and a higher proportion of dead deciduous wood. However, the average number of red-listed species was low and did not differ between the two forest categories. We detected a landscape effect connected with the intensity and length of forest management history, with the highest numbers of all and red-listed species per site in eastern Finland. Volume and diversity of dead wood were the most important variables explaining variation in species richness. Presently, key habitats in managed forests appear to contribute only little to the conservation of red-listed polypore species.  相似文献   

2.
Conservation and sustainable forestry are essential in a multi-functional landscape. In this respect, ecological studies on epiphytes are needed to determine abiotic and biotic factors associated with high diversity. The aim of the present study was to evaluate relative sensitivity of conservation targets (epiphytic bryophytes and lichens) in relation to contrasting environmental variables (tree species, tree diameter at breast height, bark crevice depth, pH, tree inclination, pH, forest stand age, area and type) in boreo-nemoral forests. The study was conducted in Latvian 34 woodland key habitat (WKH) boreo-nemoral forest stands. Generalized linear mixed models and canonical correspondence analysis showed that tree species and tree bark pH were the most important variables explaining epiphytic bryophyte and lichen composition and richness (total, Red-listed, WKH indicator species). Forest stand level factors, such as stand size and habitat type, had only minor influence on epiphytic species composition and richness. The results of the present study indicate a need to maintain the diversity of tree species and large trees, particularly Acer platanoides, Carpinus betulus, Fraxinus excelsior, Populus tremula, Tilia cordata, Ulmus glabra and Ulmus laevis in conservation of epiphytic bryophyte and lichen communities in the future.  相似文献   

3.
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Successful biodiversity conservation needs to be based on reliable data regarding the distribution and abundance of species. Red Lists summarize the status of rare and declining species. Here we present the first detailed survey (10 m × 10 m resolution) of nationally red-listed bryophytes and lichens at stand level in boreal forests. 30 managed forest production stands in boreal Sweden, soon to be harvested, were surveyed in detail regarding red-listed bryophytes and lichens. On the 180 ha totally investigated, 33 red-listed species were found, representing 35% of all forest red-listed bryophytes and lichens so far recorded from this part of Sweden. The mean number of red-listed species per stand was 10 and varied between 5 and 16. Excluding three species which were so common that, given the time-limit, it was not possible to record all of their occurrences, there were on average 6 number of observations ha−1. The presence and density exceed those earlier found in ‘key habitats’, defined as hot-spots for red-listed species. Almost all observations were made on trees, with 48% on living trees and 52% on dead. Altitude, area and stem volume explained 67% of the red-list species density. The results highlight the importance of unprotected areas for rare and declining species and point to a hitherto unacknowledged high biodiversity value of mature managed boreal forest stands, shaped by a less intense forestry than today's. It also raises questions regarding the use of red-listed species to identify areas of importance to biodiversity. Objective and systematic surveys of red-listed species in the forest landscape, including younger stands, are urgent.Der erfolgreiche Schutz der Biodiversität muss auf verlässlichen Daten über die Verbreitung und Abundanz der Arten basieren. Rote Listen fassen den Status seltener und abnehmender Arten zusammen. Hier präsentieren wir die erste detaillierte Erfassung (10 m × 10 m Auflösung) von Bryophyten und Flechten der nationalen Rote Liste auf Bestandsniveau in borealen Wäldern. Im borealen Schweden wurden in 30 bewirtschafteten Produktionswälder, die bald geerntet werden sollen, die Bryophyten und Flechten der Roten Liste im Detail erfasst. Auf den insgesamt untersuchten 180 ha wurden 33 Arten der Roten Liste gefunden, die 35% aller Wald-Bryophyten und-Flechten der Roten Liste repräsentieren, die bisher in diesem Teil Schwedens erfasst wurden. Die mittlere Anzahl derRote-Liste-Arten pro Bestand war 10 und variierte zwischen 5 und 16. Unter Ausschluss von drei Arten, die so gewöhnlich waren, dass es bei dem gegebenen Zeitlimit nicht möglich war alle ihre Vorkommen zu erfassen, gab es im Durchschnitt 6 Beobachtungen ha−1. Vorkommen und Dichten übertrafen die früher in “Schlüsselhabitaten” gefundenen, die als ‘hot spots’ bezeichnet werden. Fast alle Beobachtungen wurden auf Bäumen gemacht, mit 48% auf lebenden und 52% auf toten Bäumen. Die Höhe, das Gebiet und das Stammvolumen erklärten 67% der Dichte der Rote-Liste-Arten. Die Ergebnisse heben die Wichtigkeit nicht-geschützter Gebiete für seltene und abnehmende Arten hervor und weisen auf einen bisher nicht wahrgenommenen hohen Biodiversitätswert von alten bewirtschafteten borealen Waldbeständen hin, die von einer weniger intensiven Forstwirtschaft als der heutigen geformt wurden. Es stellen sich ebenso Fragen, die die Verwendung der Rote-Liste-Arten betreffen, um für die Biodiversität wichtige Gebiete zu identifizieren. Objektive und systematische Erfassungen der Rote-Liste-Arten in Waldlandschaften inklusive der jüngeren Bestände sind dringend.  相似文献   

5.
The three major threats to lichens in Sweden; forestry, air pollution, and structural changes in the agricultural landscape, are outlined. Forestry is the most serious. The majority of the red-listed lichens in forests are found in productive forests with a continuity in tree growth, but nearly 70% of the protected area in Sweden consists of alpine landscapes. Examples of important habitats with red-listed lichens are described, e.g. Alnus glutinosa marshes, alvar-vegetation, broad-leaved deciduous forests and different Picea abies forests. The use of selected indicator species of lichens and macrofungi (mainly red-listed species) in boreal coniferous forests provides information on continuity in tree growth of an area, and on earlier influences of forestry. Examples of indicator species for different types of forest are presented and discussed. In spite of the Swedish right of common accesso, collecting of lichens is forbidden without permission from the land-owner. Collecting in protected areas is allowed only with a permit obtained from the authorities.  相似文献   

6.
In Dutch forests the species density of vascular plants ranges from 1 to 61 species per 300 m2. The vascular plant species density is high in the coastal dunes, southern Limburg, river valleys, and fen areas. With the exception of southern Limburg, these areas constitute the Holocene part of the Netherlands. Low species densities occur in the sandy centre of the country. To a large extent, the areas of high species density of vascular plants follow the main river valleys. The bryophyte species densities range from 0 to 21 species per 300 m2. High bryophyte species densities occur mainly in the sandy centre and in the north-eastern part of the Netherlands. The highest species densities occur in fen woodlands and derelict coppices. Bryophyte species density is low in the coastal dunes and the very young woodlands in the recently reclaimed areas (polders). The species density contour maps of vascular plants and bryophytes in the Netherlands have little in common.  相似文献   

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8.
Current occurrence patterns of species associated with ancient trees may reflect higher historical habitat densities, because the dynamics of the habitat and the colonisation-extinction processes for many inhabiting species are expected to be slow. We tested this hypothesis in southeast Sweden by analysing species occurrence per parish for twelve redlisted lichen species and nine redlisted fungus species in relation with current density of big oaks, the density of oaks in the 1830s and connectivity with parishes with the species present. For most species, the occurrence was positively related with current density of habitat (for 18 species out of 21) and parish area (for 16 species). Historical habitat density was positively related with occurrence for 11 species, while connectivity with current occurrences in the surroundings was positive for the occurrence of 12 species and negative for the occurrence of two. For lichen species the connectivity measure that best explained the variation was at a larger spatial scale as compared to fungus species. Even if the density of old oaks remains in the future, inhabiting species will most likely decline because their distribution patterns are not in equilibrium with the current habitat density. Therefore, to allow long-term persistence of inhabiting species the number of old oaks should be increased. Areas where such an increase is most urgent could be identified based on species occurrence data and current habitat density, but because species data will always be incomplete data on the historical habitat distribution is valuable.  相似文献   

9.
10.
双棘长蠹属的检疫鉴定   总被引:1,自引:0,他引:1  
长期以来,双棘长蠹的英文和中文资料不但收录的种类少,而且与莱纳的权威著述在有些形态描述上不一致。本文根据莱纳的法文原著,将双棘长蠹属害虫的主要形态特征和38种的检索表结合特征图编译如下,供口岸检疫鉴定和国内林木害虫调查时作参考。  相似文献   

11.
12.
Nitrogen represents a critical nutrient in raised bogs. In Sphagna , dominating this habitat, the prevalent storage amino acid asparagine is catabolized predominantly by the enzyme L-asparaginase (EC 3.5.1.1). L-asparaginase activity has been detected in each of 10 Sphagnum species investigated. In Sphagnum fallax Klinggr. (Klinggr. clone 1) cultivated under axenie conditions in continuous feed bioreactors, the enzyme displayed a light dependent increase in activity. We separated two isoforms, designated L-asparaginase 1 and 2, characterized by their different elution patterns from an anion-exchange column. In stem segments only L-asparaginase 2 could be detected, whereas in capitulae L-asparaginase 1 represented the dominating isoform. Purified chloroplasts displayed no L-asparaginase activity. Almost the entire activity was located in the cytosohc fraction. L-asparaginase 1 and 2 have been purified 82-fold and 188-fold, respectively, by ion-exchange, size-exclusion and hydrophobic interaction chrornatography. Identical pH optima (8.2) and molecular weights (126 000) were determined. The Km values for asparagine (7.4 m M for L-asparaginase 1 and 6.2 m M for L-asparaginase 2) were in the range of those described for higher plants. On the other hand Sphagnum L-asparaginase is comprised of four subunits as are the L-asparaginases of microorganisms. So, the characteristics of the bryophyte enzyme appear to be intermediate between those from higher plants and those from microorganisms.  相似文献   

13.
The effects of regular litter removal and annual variation in temperature and precipitation on seedling recruitment of species differing in their seed size and mode of dispersal were studied in a 16-year (1984-1999) experiment in a mixed oak-pine wood in southern Poland. Litter was the most important factor in determining spatial variability in seedling recruitment, whereas differences in climatic conditions among years, especially temperature fluctuations in late winter and early spring, determined the temporal variability in seedling recruitment. Compared with control plots, significantly more new individuals of bryophytes and seedlings as well as a number of new species of vascular plants were noted in the litter-removal plots over the 16-year study. Litter strongly impeded seedling emergence of small-seeded species. The negative effect of litter on seedling recruitment of large-seeded species and the recruitment of new shoots in species growing clonally was much weaker. There was a significant positive correlation between the numbers of seedlings in the litter-removal and control plots and temperatures in January to March. In the litter-removal plots this mainly affected small-seeded species. Seedling recruitment was less consistently related to variation in precipitation. Positive relationships were found only between the number of seedlings of large-seeded species in the litter-removal plots and precipitation in July of the current year and in September of the previous year, and between the number of seedlings in the control plots and precipitation in September and November of the previous year.  相似文献   

14.
A survey was carried out to determine the density and species composition of germinable seed in the surface soil layers of 30 plots within a coniferized lowland woodland in East Kent in order to establish the resources available for habitat creation in the event of some areas being modified during a proposed holiday village development. The selected plots included conifer plantations (up to 69 years old), broad-leaved plantations and the semi-natural broad-leaved edges that remain on parts of the perimeter of the site which were used as the control. A total of 13 682 seedlings emerged from the soil samples during the four-month germination trials. Fifty-two species were identified of which eight were ancient woodland indicator species for south-east England. The most abundant species represented in the seed banks were: Juncus effusus, Rubus fruticosus, Carex sylvatica, Betula pendula and Agrostis tenuis. Between-site comparisons of coniferous plots of different ages revealed a marked reduction in the seed species and seed density in plantations over 65 years old. Results of soil nutrient and texture analyses ruled out the likelihood of edaphic factors being responsible for between-site differences in seed bank composition. Seed species richness and diversity (Shannon-Wiener diversity index) were greatest in the semi-natural broad-leaved edges, but the diversity index used also showed that two replanted conifer sites had high values despite few species being present. The usefulness and limitations of diversity indices in the context of seed bank studies is discussed. From the results of the study, management proposals for the site have been put forward in order to maintain floristic diversity and mitigate the impact of the proposed development.  相似文献   

15.
Galli L  Capurro M  Torti C 《ZooKeys》2011,(146):19-67
The Italian Protura were studied basing on 5103 specimens from 198 sampling areas, along with bibliographic data from 49 collecting sites. 17 out of the 20 Italian regions are covered. As a result, 40 species have been identified (belonging to 8 genera and 4 families), 6 of which are new records for the Italian fauna.A key to the Italian species is reported, followed by a series of distribution maps and brief remarks for some of them. A preliminary biogeographical overview allowed us to delineate the chorological categories of these species, 10 of which are actually known only in Italy. The comparison with the species richness known for some best studied Central and Eastern European Countries leads us to speculate that widening our research, Italian Protura check-list will be much implemented.  相似文献   

16.
To examine the effects of human land use and disturbance on butterfly communities we compared the diversity and structure of communities in relatively undisturbed, semi-natural grassland habitats and highly disturbed, human-modified ones. Comparisons were based on transect counts conducted at 6 study sites at the foot of Mt. Fuji in the cool temperate zone of central Japan during 1995. Out of the six community parameters used in the analyses, the species richness, species diversities H and 1/, and dominance indices were significantly different between the two habitat types stated above. That is, butterfly communities in semi-natural habitats had higher species richness and diversity, and lower dominance indices than those in human-modified ones. This suggests that heavy land modification and disturbance to semi-natural habitats change greatly its butterfly community structure, which, indeed, leads to decreasing species richness and diversity mainly due to the loss of species that are confined to semi-natural habitats. Through the comparisons of various species' characteristics, it was found that the species confined to semi-natural habitats had lower population abundance, fewer generations per year, more restricted local distributions, and narrower geographic range size in Japan than the other component species. Based on our results, it is critical that the persistence of the species that are limited to semi-natural habitats be ensured in order to maintain high species richness and diversity in grassland butterfly communities. Thus, conservation plans that retain as much semi-natural habitat as possible within the process of human grassland use, development, and modification are needed.  相似文献   

17.
S Serri  Z Pan  MA Bologna 《ZooKeys》2012,(219):81-86
A new species of Mylabris of the nominate subgenus is described and figured. This species is apparently endemic to the south-eastern Iranian province of Kerman and seems to be phenetically very distinct from all other species of this subgenus, primarily because of the unique elytral pattern. A key to the species of the nominate subgenus distributed in Iran is also presented.  相似文献   

18.
We examined the capability of hyperspectral imagery to map habitat types of under-storey plants in a moist tall grassland dominated by Phragmites australis and Miscanthus sacchariflorus, using hyperspectral remotely-sensed shoot densities of the two grasses. Our procedure (1) grouped the species using multivariate analysis and discriminated habitat types (species groups) based on P. australis and M. sacchariflorus shoot densities, (2) used estimated shoot densities from hyperspectral data to draw a habitat type map, and (3) analyzed the association of threatened species with habitat types. Our identification of four habitat types, using cluster analysis of the vegetation survey coverage data, was based on P. australis and M. sacchariflorus shoot density ratios and had an overall accuracy of 77.1% (kappa coefficient = 0.71). Linear regression models based on hyperspectral imagery band data had good accuracy in estimating P. australis and M. sacchariflorus shoot densities (adjusted R 2 = 0.686 and 0.708, respectively). These results enabled us to map under-storey plant habitat types to an approximate prediction accuracy of 0.537. Among the eight threatened species we examined, four exhibited a significantly biased distribution among habitat types, indicating species-specific habitat use. These results suggest that this procedure can provide useful information on the status of potential habitats of threatened species.  相似文献   

19.
A new species of Hycleus belonging to the phaleratus group, and close to Hycleus phaleratus, is described. The new species, Hycleus marcipoli, is distributed in China (Gansu and Taiwan), Laos, and northern Thailand. A key to the Chinese species of this group is presented.  相似文献   

20.
H Bharti  R Kumar 《ZooKeys》2012,(207):11-35
Two new species of Tetramorium Mayr, namely Tetramorium shivalikensesp. n. and Tetramorium triangulatumsp. n. are described. Tetramorium triangulatumsp. n. belongs to the inglebyi-species group and is described based on worker, queen and male caste, while Tetramorium shivalikensesp. n. belongs to the ciliatum-species group and is described based on worker caste only. Three species viz., Tetramorium caldarium (Roger), Tetramorium tonganum Mayr and Tetramorium urbanii Bolton represent first records from India. The male caste is described for the first time in the case of Tetramorium tonganum. Among these, Tetramorium caldarium is a tramp species which extends its limit to India as well. A revised key to the Indian ants of this genus is also provided herewith.  相似文献   

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