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1.
Forestry is obliged to record as well as maintain and/or enhance biological diversity in forests due to national and international
agreements. Accordingly, it is necessary to work out methodological approaches for the assessment of biodiversity in forests.
In the study presented here, we focus on the total plant species pool (563 vascular plant and bryophyte species) of pine (Pinus sylvestris L.) forests in NE Germany to identify indicators for plant species richness. We distinguished several groups like “herb”,
“grass-like”, “woody”, “endangered”, and “exotic species”, for which we detected indicators for low (class #1), intermediate
(class #2), and high (class #3) species numbers. From a total of 84 species, which were identified by a three-step procedure,
most indicators were found for class #3. Only few indicators have been revealed for intermediate species numbers, i.e. class
#2. With help of Ellenberg’s ecological indicator values and information on the main occurrence in Central European vegetation
types and plant communities, respectively, we characterized the indicator species ecologically. The ecological site preferences
of the indicator species in general reflect the fact that species richness is highest in base-rich, light, and anthropogenically
disturbed pine forests. On the contrary, species-poor forests were revealed by indicators, which mainly occur on acidic sites.
It is concluded that a considerable set of indicators for species richness can help facilitate biodiversity assessments in
forestry and ecosystem restoration practice.
Electronic Supplementary Material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
2.
3.
Cornelia Ebert Ditmar Huckschlag Holger K. Schulz Ulf Hohmann 《European Journal of Wildlife Research》2010,56(4):583-590
Reliable estimation of population size remains a major challenge in wildlife ecology and management. Lately, genotyping of
non-invasively obtained tissue samples integrated in a modified capture–recapture approach provides new perspectives. Faeces,
moulted feathers, or hairs can be easily sampled in the field. However, an important assumption is homogeneity of sampling
across the population. In this pilot study, we tested the suitability of baited barbed wire hair sampling stations (‘hair
traps’) for homogeneous genetic sampling for population estimation. A video system based on a new network internet protocol
was used to observe the behaviour of wild boar visiting baited hair traps for gaining information about potential heterogeneities
in the individual sampling probability. Within 92 monitoring nights at two sampling stations, 216 wild boar visits were recorded
and 142 hair samples containing 2,124 single hairs were collected. Video analysis revealed distinct differences in the behaviour
of wild boar with respect to the sampling station which are most likely to result in heterogeneous individual sampling probabilities.
Adult and subadult animals differed in their behaviour dependent on their group status. This result indicates that hair sampling
with baited hair traps is not suitable for representative non-invasive sampling of free ranging wild boar populations. 相似文献
4.
Common methods to assess diversity and abundance of Orthoptera are sweep netting, transect counts and box-quadrat sampling.
Pitfall trapping, by contrast, is rarely used, and the value of this method is still being questioned. In 2008, we studied
Orthoptera species richness and abundance in five vegetation types along a gradient of dune succession on the Baltic Sea island
of Hiddensee (NE Germany) by comparing transect-count and pitfall-trapping data. Using transect counts, 12 species were detected
in the study area. With pitfall traps, three chorto- and thamnobiont Ensifera species (C. dorsalis, M. roeselii and T. viridissima) were not caught at all, and it was only in low-growing and sparsely-vegetated grey dunes that all present species were detected.
With pitfall traps, the proportion of present species recorded strongly declined with increasing height and density of the
vegetation type. Assuming that transect counts are a good proxy for relative Orthoptera densities, densities ascertained by
pitfall traps are strongly biased by vegetation structure and locomotive behaviour of the species. More than 80% of all individuals
were caught in sparsely-vegetated grey dunes. Frequency patterns of the species also differed. Using pitfall traps, especially
chortobiont species were significantly underrepresented. Qualitative and quantitative sampling of Orthoptera using pitfall
traps seems only reasonable in habitats with low and sparse vegetation and a high proportion of geobiont species. 相似文献
5.
- Bees are prolific, vital pollinators in agricultural and natural settings, but some taxa are declining. Surveying bees is crucial to understand the needs of these taxa; however, we lack a fine-grained understanding of assemblages associated with different sampling methods that would enable us to analyse data range-wide.
- Here we examine the difference in abundance and richness of bees (bee bowls and vane traps only) and bumble bees (genus Bombus; bee bowls, blue vane traps and target netting) sampled with these methods from mixed-grass prairie to alpine habitats in Wyoming, USA.
- We collected four times more bees and twice as many genera of bees in vane traps than bee bowls. Vane traps captured more individuals of abundant genera than bee bowls.
- Bombus species abundance did not vary between vane traps and target netting; however, richness was higher in vane traps. Bee bowls captured few Bombus species.
- Overall, we recommend using vane traps to sample most bees, and a combination of vane traps and target netting to collect bumble bees. We evaluated how three sampling techniques perform when surveying for wild bees, which will aid in identifying declining species as well as monitoring species of conservation concern.
6.
A hoverfly (Syrphidae) community was investigated in a cultivated wheat field and the adjacent hedgerow near Debrecen (Hungary). We monitored the change of species richness and abundance of hoverflies along three transects in the hedgerow and in the wheat field in different distances (10 m, 20 m) from the hedgerow. The effect of sampling methods on the number of hoverfly species and individuals was analyzed. Two sampling methods were used to catch hoverflies: netting and pan traps. The whole sampling period was divided into three subperiods, which are early (22nd April–2nd June), middle (11th June–1st August) and late (6th August–11th September). Altogether 1,214 individuals of 22 species were sampled. Fourteen species with 78% of individuals belonged to the aphidophagous group, feeding on aphids as larvae. Altogether 861 individuals of 22 hoverfly species were sampled by netting and 353 individuals of 10 species by pan traps. The total number of hoverfly species was significant lower in the late period than in the early. The total abundance was higher in the middle period compared to the early. The species richness and abundance of aphidophagous species followed a similar pattern as the total species values. The species richness and abundance of hoverflies were significant higher in 10 m and 20 m distance in the wheat field than along the hedgerow. The results suggest that the pan traps were less efficient in the hedgerow than the netting, but in the wheat field they sampled more hoverflies because of visually alluring effect on hoverflies in the absence of flowers. 相似文献
7.
Bitou bush (Chrysanthemoides monilifera ssp. rotundata) is a major environmental weed of littoral habitats on the southeastern coast of Australia. This study investigates the impacts
upon selected arthropod assemblages of habitat invasion by this weed. Sixteen sites were placed at four geographic localities
within nature reserves between Forster and Budgewoi on the coast of New South Wales. The sampling design included two spatial
scales (between and within localities) and eight repeat samples (taken at two scales of temporal separation). Arthropods were
collected from both arboreal and epigaeic micro-habitats. Specimens of ants (Hymenoptera: Formicidae), beetles (Coleoptera),
true bugs (Heteroptera) and spiders (Araneae) were identified to species level. Differences in α diversity and species abundance
distributions between the taxonomic assemblages are described, along with comparisons of data contrasts between bitou bush-free
(“control”) and bitou bush-invaded (“impact”) habitats and between geographic localities. A subsidiary impact associated with
herbicide application for control of the weed is also examined. Analysis of environmental differences indicates that bitou
bush acts as a dampening agent, reducing the degree of seasonal fluctuation in factors such as leaf litter cover. Arboreal
Heteroptera were the only group to show consistent evidence of significant differences in taxon richness or abundance between
control and impact treatments within a locality, seen as a disruption of normal seasonal variation in diversity in bitou bush-impacted
sites. Significant differences between geographic localities were more common, suggesting an effect at broader spatial scales.
Evidence for arthropod assemblages characteristic of specific vegetation types was detected for several groups, as were changes
in arthropod assemblage composition following application of herbicide for bitou bush control. 相似文献
8.
Summary Strains of Staphylococci originally resistant to chloramphenicol, tetracycline and erythromycin, or made resistantin vitro to tyrothricin and streptomycin, were transformed into the “L” form and subcultured in this phase for more than twenty passages.
The “L” colonies of the entire series could be reversed to bacterial forms. From all theisolated staphylococci strains the
phage pattern was found to be maintained; slight changes in the number of active phages and the degree of activity are deemed
to be insignificant. New types were never found. The strains made resistant to tyrothricin and streptomycin remained insensitive,
those, however, that were originally resistant to chloramphenicol, tetracycline and erythromycin, became sensitive after a
number of passages in the “L” phase. This loss of resistance—the only significant change from the original strains—is thought
not to be due to mutation.
Working with grants of the foundation “De Drie Lichten” and the “Stichting ter Bevordering van Medisch-Wetenschappelijk Onderzoek”. 相似文献
Résumé Des souches de Staphylocoques sensibles à la pénicilline, mais naturellement résistantes au chloramphénicol, à la tétracycline et à l'érythromycine, aussi bien que des souches rendues insensibles à la tyrothricine ou à la streptomycine, étaient transformées en phase “L”. Dans cette phase plus de vingt subcultures étaient faites; les colonies “L” de chaque passage pouvaient être reversées en phase bacillaire. Toutes les souches récupérées avaient conservé le type bactériophagique des souches d'origine; l'augmentation du nombre des phages actifs et le changement du degré de leur activité ne peuvent être considérés signifiants. Nous n'avons jamais trouvé de nouveaux types. Les souches résistantes à la streptomycine et à la tyrothricine restaient insensibles; celles au contraire, qui étaient naturellement résistantes a la tétracycline, à l'érythromycine ou au chloramphénicol devenaient sensibles après peu de subcultures en phase “L”. Cette perte de résistance est considérée être d'origine non-mutationelle. L'existence d'un cycle “L” des Staphylocoques s'est averée ainsi.
Working with grants of the foundation “De Drie Lichten” and the “Stichting ter Bevordering van Medisch-Wetenschappelijk Onderzoek”. 相似文献
9.
Arthropods were sampled using pitfall traps, sticky traps, sweep netting, Malaise traps and visual sampling at a national botanic garden, KwaZulu-Natal, South Africa, where the taxonomic impediment is great. The aims were to compare two sites, one of native vegetation and the other of mainly exotic plants, to determine the possible localized extent of biodiversity change across the land mosaic, and to test and compare methodologies and indicator taxa and to make recommendations for ecological landscaping of a botanic garden. Species richness and evenness varied considerably with sampling technique used. From results of a single replicate of data from all trapping methods including 821 arthropod species and 3831 individuals, a number of conclusions could be drawn. Trapping procedures such as sweep netting and pitfall traps, which focus on species with restricted mobility and/or host plant requirements, indicated greatest differences in diversity between two closely located sites. Taxa varied in sensitivity to microlandscape, again depending on the extent of their mobility. Cicindelid and carabid beetles were particularly good indicators of habitat disturbance and type. The management recommendations are that in a species-rich urban botanic garden such as this, as many ecotopes as possible should be preserved or created. These should vary in topography, landscape characteristics and vegetation composition, with as much connectivity as possible. This is a feasible blanket approach to give home to a large number of nameless species and morphs. Patches of different ecotopes should not be separated by more than a few metres by expanses of mown lawn which isolates much of the fauna. 相似文献
10.
Quantifying biodiversity: procedures and pitfalls in the measurement and comparison of species richness 总被引:15,自引:0,他引:15
Species richness is a fundamental measurement of community and regional diversity, and it underlies many ecological models and conservation strategies. In spite of its importance, ecologists have not always appreciated the effects of abundance and sampling effort on richness measures and comparisons. We survey a series of common pitfalls in quantifying and comparing taxon richness. These pitfalls can be largely avoided by using accumulation and rarefaction curves, which may be based on either individuals or samples. These taxon sampling curves contain the basic information for valid richness comparisons, including category–subcategory ratios (species-to-genus and species-to-individual ratios). Rarefaction methods – both sample-based and individual-based – allow for meaningful standardization and comparison of datasets. Standardizing data sets by area or sampling effort may produce very different results compared to standardizing by number of individuals collected, and it is not always clear which measure of diversity is more appropriate. Asymptotic richness estimators provide lower-bound estimates for taxon-rich groups such as tropical arthropods, in which observed richness rarely reaches an asymptote, despite intensive sampling. Recent examples of diversity studies of tropical trees, stream invertebrates, and herbaceous plants emphasize the importance of carefully quantifying species richness using taxon sampling curves. 相似文献
11.
12.
Ricardo Figueroa Victor Ruíz Xavier Niell Elizabeth Araya Alejandro Palma 《Hydrobiologia》2006,571(1):409-417
The macrozoobenthos colonization process on artificial substrata in lotic environments was evaluated. Two seasonal periods,
autumn–winter and spring–summer, of a relatively undisturbed fluvial system, the Estero Nonguén (VIII Region, Chile), have
been studied. Five stations, two in riffles and three on sandy bottoms, extending from a head water stream to 5 km down river,
were sampled. For all stations and for each season the results were as follows: (a) 32% of the total number of taxa found
in this study colonized the artificial substrata on the first day of exposure, (b) the taxa that colonized sandy bottoms were
typical for riffle, (c) the colonization process showed the same abundance, specific and cumulative richness and diversity
patterns over time, and (d) equilibrium was reached approximately 2 weeks after initial exposure. This suggests that “Estero
Nonguén” stream presents a nearly pristine condition and can be considered as a reference site to carry out biodiversity and
ecosystem functionality studies, and giving information on time recovery for sectors previously disturbed.
Electronic supplementary material Electronic supplementary material is available for this article at
and accessible for authorised users. 相似文献
13.
Pedro Cardoso Sérgio S. Henriques Clara Gaspar Luis C. Crespo Rui Carvalho Jesper B. Schmidt Pedro Sousa Tamás Szűts 《Journal of Insect Conservation》2009,13(1):45-55
Intensive fieldwork has been undertaken in Portugal in order to develop a standardized and optimized sampling protocol for
Mediterranean spiders. The present study had the objectives of testing the use of semi-quantitative sampling for obtaining
an exhaustive species richness assessment of spiders and testing the effects of day, time of day, collector and sampling method
on the collected species richness and composition of a Mediterranean scrubland. The collecting summed 224 samples corresponding
to one person-hour of effective fieldwork each. In total, 115 species were captured, of which 110 were recorded inside a delimited
one-hectare plot, corresponding to more than 70% of the about 160 estimated species. Although no estimator reached the asymptote,
the Michaelis-Menten curve behaviour indicates that the estimated richness should be accurate. Most different sampling approaches
(day, time of day, collector and sampling method) were found to influence richness, abundance or composition of the samples
to some extent, although sampling method had the strongest influence whereas “collector” showed no effect at all. The results
support the idea that the only variables that need to be controlled in similar protocols are the sampling methods and the
time of day when each method is executed. We conclude that populations in structurally simple habitats present narrower peaks
of adult abundance, which implies higher percentages of juveniles in samples. Finally, results also indicate that habitats
with a relatively simple structure like scrublands may require as much sampling effort, in order to reach similar proportions
of captured species in relation to the estimated richness, as habitats that are much more complex. 相似文献
14.
Giovanni Bettacchioli Mauro Taormina Fabio Bernini Massimo Migliorini 《Journal of Insect Conservation》2012,16(2):249-261
Studies on disturbance regimes involving carabid beetles have mainly focused on forest habitats. We therefore decided to analyze
the effects of disturbance on carabid communities in a wetland remnant (Lake Chiusi, central Italy). Results highlighted the
presence of a disturbance gradient affecting the species richness and trait-displacement of carabid communities. Carabids
were sampled with pitfall traps from March to October 2008 at nine randomly selected sample stations; a set of landscape attributes
were also collected. Principal Component Analysis (PCA) and generalized linear mixed models (GLMMs) were used to link the
distribution of carabid life-history traits and species richness with the most informative combination of landscape attributes.
The first PCA axis (PC1) showed significant correlation with “distance to the lake shoreline” and “perimeter-area ratio”,
highlighting the presence of a disturbance-axis. The second and third axes accounted only for a trivial portion of the total
variance. GLMMs revealed a progressive decrease in the number of hygrophilous species from the core of the wetland to its
outer areas. Similar trends were observed for species richness and for predator species with good dispersal ability and larval
period in summer. Our results highlight the importance of taking into account community-wide functional implications in landscape
ecology studies. 相似文献
15.
《African Journal of Aquatic Science》2013,38(1):15-23
A study was undertaken in November 2003 to derive a suitable sampling technique for collecting a representative sample of aquatic macroinvertebrates from a selected emergent vegetation biotope in a palustrine wetland, Melmoth Vlei, KwaZulu-Natal, South Africa. The aim was to undertake a preliminary investigation on the development and testing of a macroinvertebrate sampling technique for use in emergent sedge-dominated palustrine wetlands (sensu Cowardin et al. 1979), which could contribute to the development of a South African wetland health biomonitoring programme. Sweep nets and activity traps were evaluated for their effectiveness in terms of macroinvertebrate collection. Sweep net sampling was tested over a range of sweep intensities to determine the minimum number of sweeps required to collect a representative sample. Sampling efficiency of activity traps placed at four depths was tested, and taxon diversity and composition of sweep net and activity trap samples were compared to determine whether activity traps are required to supplement sweep net data. A total of 32 taxa (identified mainly to family level) were identified in the samples collected. Taxon diversity and composition did not differ in the activity traps placed at the four depth locations. Taxon diversity did not differ significantly between different sweep intensities. This may be a result of high variability of macroinvertebrate distribution within a wetland. There is evidence, however, to suggest that this result is due to an inadequate sample size. There was a significant difference in taxon composition between the different sweep intensities (P < 0.05) and between activity trap and sweep net samples (P < 0.05). Sixty-eight percent of taxa appeared more frequently in sweep net sampling than in activity trap sampling. Two taxa were found exclusively in activity traps, although the numbers of these taxa collected were not significant, and they do not represent any unique trophic group. Based on these findings, it was concluded that activity traps are not required to supplement sweep net data, and a technique using a sweep net with a sweep intensity of five would be suitable for collecting a representative sample of macroinvertebrates from a palustrine wetland. 相似文献
16.
Chyuan-Yih Lee 《Bulletin of mathematical biology》1980,42(4):489-505
To explain the sodium conductance change using Wei's dipole model (Wei, 1969), we may expect that during depolarization the
dipole's population difference, ΔN, is first reduced and then returns more slowly to its resting value. This paper shows that the experimental results of gating
currents support this idea. Such time course of ΔN, however, is not a usual relaxation process. To account for the unusual behavior of ΔN, we propose two additional assumptions: (1) there exists a special coupling system (probably the intramolecular vibrations)
whose coupling strength with the dipoles is much stronger than with the thermal bath (intermolecular vibrations), and (2)
there also exist “traps” for the dipole's excitation energy so that this energy is transformed into other energy forms at
a rate increasing with the increase of depolarization. Experiments suggest that the traps are proteins located at the inner
membrane surface. 相似文献
17.
Hanna Ciecierska 《Hydrobiologia》2006,570(1):141-146
Urban lakes belong to various groups, for example from “young” to “old” with regard to development, and from “natural” to
“anthropogenic” with respect to transformations due to human activity. The majority of these lakes are eutrophic and polytrophic,
but special attention should be paid to mesotrophic ones, with relatively unchanged vegetation, with species of the class
Charetea, e.g. Lake Redykajny (43.3% of the phytolittoral) or Lake Tyrsko (44.0% of the phytolittoral). 相似文献
18.
Jun-Ichi Kojima 《The Botanical review》2003,69(1):44-58
Acceptable methods of defining taxon (or clade) names in the draft PhyloCode, or so-called phylogenetic nomenclature, are
“node based,” “stem based,” and “apomorphy based.” All of them define a clade name by pinpointing a node; whereas node-based
and stem-based definitions require two or more taxon “specifiers” to define names, an apomorphy-based definition requires
two specifiers of different types; namely, a single-taxon specifier and a character specifier. The taxon specifier in an apomorphy-based
definition is completely different from the “type” in the Linnaean system. Taxon (or clade) names in the PhyloCode are characterized
in two entirely different manners: One is a name that does not change, either in its orthography or in the contents of the
taxon referred to by it (or its meaning) over time; the other is a name that is just like a pure mark and thus has no meaning.
Communication through such PhyloCode names is very ineffective or impossible. 相似文献
19.
Gonzalo Castillo-Campos Gonzalo Halffter Claudia E. Moreno 《Biodiversity and Conservation》2008,17(7):1701-1714
The floristic diversity of Mexican tropical deciduous forests (TDF) is of critical importance given the high species richness
(alpha diversity), species turnover (beta diversity), and the intense deforestation rates. Currently, most TDF landscapes
are mosaics of agricultural land, secondary vegetation, and patches of relatively undisturbed primary vegetation. Here we
illustrate how both primary forest remnants and secondary vegetation patches contribute to the floristic diversity of TDF
in a landscape of volcanic origin in central Veracruz, Mexico. Our objectives were to assess sampling efficiency and inventory
completeness, to compare mean and cumulative species richness between primary forest and secondary vegetation sites, and to
analyze beta diversity between vegetation types. In an area of 12,300 m2 we recorded 105 families, 390 genera, and 682 species.
Species inventories for both vegetation types were about 80% complete. Secondary vegetation is more alpha diverse than primary
forest, both in terms of cumulative and mean species richness. We found a remarkably high beta diversity between vegetation
types (75% of complementarity, 91.60% of mean dissimilarity). We also identified the species that contribute the most to similarity
within vegetation types and to dissimilarity between vegetation types. Our results support the idea that assessing biodiversity
on the landscape scale is an appropriate way to ascertain the impact of human activities. For this land mosaic, conservation
of the flora would not be possible by focusing solely on primary forest remnants. We propose the implementation of a network
of small conservation areas with a flexible structure, following the “archipelago reserve” model. 相似文献
20.
The bottom fauna (16–30 m depth) of Kongsfjord (Svalbard) was investigated by direct observation, a SCUBA-diver operated
suction sampler (quantitative) and underwater photography (semi-quantitative). The fauna on horizontal surfaces showed low
similarity to that on vertical faces and overhangs, and had larger species heterogeneity between sampling sites. This was
due to sedimentation and ice-rafted pebbles and stones creating “soft-bottom habitats” on the rocky bottom. Suction sampling
resulted in collection of 73 taxa, including some species usually regarded as “soft-bottom” inhabitants. Fewer species were
observed on the photographs, demonstrating the selectivity of this technique, but underwater photography may be a useful “non-destructive”
method for obtaining information about conspicuous epifaunal taxa.
Accepted: 18 July 2000 相似文献