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991.
Population dynamics of wireworms (Coleoptera,Elateridae) in arable land after abandonment 总被引:1,自引:0,他引:1
The community of elaterid larvae of three sites (field and two fallows), representing different stages of secondary succession,
were studied using soil sampling from 1986 to 1993. All three sites were abandoned arable land: a field cultivated until 1991,
a fallow I abandoned in 1986, and a fallow II abandoned about 1976. The fallow II was used as a meadow after abandonment and
was regularly mown until 1985, when cultivation stopped. Six species of Elateridae larvae were found at all three study sites.
In the field, Agriotes obscurus, Athous niger, Athous subsuscus, Dalopius marginatus and Athous vittatus were found, A. niger and A. obscurus being the most abundant species. During cultivation, larval densities were very low, however, larval abundance increased
up to 8.8 ± 8.3 ind. m-2 when cultivation stopped. Only small A. obscurus larvae were found during cultivation, whereas larval size increased after abandonment. In fallow I A. obscurus, A. niger, A. subsuscus, D. marginatus, and Agrypnus murinus were found and the average annual abundance fluctuated between 0.8 ± 1.4 to 40.8 ± 10.9 ind. m-2 with A. obscurus being the most abundant species. Fallow II supported the highest densities of wireworms from all plots studied (71.2±35.2
to 280.0±24.8 ind. m-2). A. obscurus, A. niger, A. subsuscus and D. marginatus were found in fallow II. The abundance of all larval Elateridae as well as the dominant species A. obscurus decreased during the study period, while simultaneously the occurrence of small sized A. obscurus larvae decreased. The frequency of cultivation and time elapsed since last cultivation appeared to be the most important
factors affecting elaterid occurrence in the field and fallow I. In fallow II, the decrease in abundance correlates with the
accumulation of a dense litter layer, which may correspond with soil surface structure, plant community changes or predator
pressure. 相似文献
992.
The influence of depth,site exposure and season on the intensity of iceberg scouring in nearshore Antarctic waters 总被引:2,自引:3,他引:2
Ice scour disturbance has a significant effect on the physical and biological characteristics of polar benthos. A series of
grids, each consisting of 25 markers, were deployed along depth transects and replicated at two contrasting study sites at
Adelaide Island, West Antarctic Peninsula. Markers were surveyed and replaced every 3 months for 2 years in order to assess
the frequency and intensity of iceberg impacts. Depth, site, season and year were all highly significant factors influencing
ice scouring frequency. We observed a high variation in the duration of winter fast ice between sites and years, which had
a marked effect on ice scouring frequency. The ecological effects of the disturbance regime are likely to include depth zonation
of benthic assemblages, patchiness of communities at varying stages of recovery and the near denudation of sessile fauna in
the shallow subtidal.
相似文献
Dan A. SmaleEmail: |
993.
994.
A new approach to rapid, genome-wide identification and ranking of horizontal transfer candidate proteins is presented. The method is quantitative, reproducible, and computationally undemanding. It can be combined with genomic signature and/or phylogenetic tree-building procedures to improve accuracy and efficiency. The method is also useful for retrospective assessments of horizontal transfer prediction reliability, recognizing orthologous sequences that may have been previously overlooked or unavailable. These features are demonstrated in bacterial, archaeal, and eukaryotic examples. 相似文献
995.
Power-law-like distributions in biomedical publications and research funding 总被引:1,自引:0,他引:1 下载免费PDF全文
Gene annotation, as measured by links to the biomedical literature and funded grants, is governed by a power law, indicating that researchers favor the extensive study of relatively few genes. This emphasizes the need for data-driven science to accomplish genome-wide gene annotation. 相似文献
996.
Background
Affymetrix GeneChip technology enables the parallel observations of tens of thousands of genes. It is important that the probe set annotations are reliable so that biological inferences can be made about genes which undergo differential expression. Probe sets representing the same gene might be expected to show similar fold changes/z-scores, however this is in fact not the case. 相似文献997.
Max Bylesjö Daniel Eriksson Andreas Sjödin Stefan Jansson Thomas Moritz Johan Trygg 《BMC bioinformatics》2007,8(1):207
Background
During generation of microarray data, various forms of systematic biases are frequently introduced which limits accuracy and precision of the results. In order to properly estimate biological effects, these biases must be identified and discarded. 相似文献998.
Rui P Galao Nicoletta Scheller Isabel Alves-Rodrigues Tanja Breinig Andreas Meyerhans Juana Díez 《Microbial cell factories》2007,6(1):32
The yeast Saccharomyces cerevisiae is a well-established model system for understanding fundamental cellular processes relevant to higher eukaryotic organisms.
Less known is its value for virus research, an area in which Saccharomyces cerevisiae has proven to be very fruitful as well. The present review will discuss the main achievements of yeast-based studies in basic
and applied virus research. These include the analysis of the function of individual proteins from important pathogenic viruses,
the elucidation of key processes in viral replication through the development of systems that allow the replication of higher
eukayotic viruses in yeast, and the use of yeast in antiviral drug development and vaccine production. 相似文献
999.
Alessio Mortelliti Giovanni Amori Giampiero Sammuri Luigi Boitani 《Acta theriologica》2007,52(1):75-84
We studied the factors affecting the distribution of an endemic shrewSorex samniticus Altobello, 1926 in the Province of Siena, central Italy. Distribution data were obtained by examining pellets from 31 barn
owlTyto alba sites (roosts) over a period spanning from 1974 to 2005. We constructed a model using logistic regression analysis on presence/absence
data. Results show that an increase in forest dominated byQuercus cerris andCastanea sativa led to the local extinction of this species. Results were confirmed through the examination of one box, with 3044 prey items
deposited in layers, that documents the expansion of the species in that area following increased logging ofQuercus cerris andCastanea sativa forests. Cessation of logging has again led to the absence of the species from the area. We discuss these results from the
perspective of ecological network planning, showing that utilisation of non-detailed maps, such as Corine Land Cover, that
do not distinguish between the various kind of broadleaved forests is inadequate to describe the finer grade of habitat selection
of this small mammal. 相似文献
1000.