ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Numerische Mathematik 45 (1984), S. 403-409 
    ISSN: 0945-3245
    Keywords: AMS-MOS 65F15,20
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Summary In this paper it is shown how a triangular product of Householder reflections can be updated with an arbitrary elementary orthogonal transformation. The amount of work required is 5/2n 2 multiplications for absorbing an arbitrary reflection and 3n 2 multiplications for absorbing a plane rotation on subsequent indices.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-5117
    Keywords: Helochares ; habitat ; geographical distribution ; environmental variables ; life-cycle ; Index of Representation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Adult water beetles were collected from 841 localities in the Netherlands. The distribution maps of the three species of the genus Helochares (Coleoptera; Hydrophilidae) in the Netherlands are given. They are based on specimens from museum collections and this investigation. H. lividus occurs all over the Netherlands, except for the north-east. This northern limit of its European distribution area coincides with the 8.5°C isotherm for the mean year temperature. H. obscurus is limited in its distribution to clay and peat-bog, but in the sandy coastal dune area H. obscurus replaces H. punctatus. H. punctatus is limited in its distribution to soils consisting of peat-moor or sand, but it is absent from the coastal dune area. Co-existence of H. lividus with either H. obscurus or H. punctatus occurs regularly. Co-existence of H. obscurus and H. punctatus has been observed only once, these species exclude each other by different ecological requirements. H. lividus and H. obscurus show two optima in abundance during the year which corresponds with a univoltine life-cycle. H. punctatus shows no clear maximum in abundance. However, on the basis of the presence of females carrying egg-cases and the presence of teneral adults a univoltine life-cycle for all three Helochares spp. can be deduced. A small proportion of the beetles hibernates either as larva or as pupa and emerges in spring. The distribution of Helochares spp. has been related to some environmental variables using the Index of Representation. H. lividus has a clear preference for waters with a high pH, high conductivity and high chlorinity with a luxurious vegetation of floating leaved and submerged plants on mineral soils. Occasionally running waters or waters with a low current velocity are preferred. Preferred habitats are regulated lowland streams, clay- and sand-ditches, and clay- and sand-canals. H. obscurus has a clear preference for stagnant waters with a high pH, high conductivity and high chlorinity (but the optimum is lower than for H. lividus) with a luxurious vegetation of floating leaved and submerged plants. Preferred habitats are clay- and sand-ditches. H. punctatus has a very clear preference for waters with a low pH, low conductivity and low chlorinity. With respect to vegetation and type of current the species shows no significant preferences or aversions. Preferred habitats are moorland pools, peat-canals and peat-cuttings.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-5125
    Keywords: Trichostegia minor ; woodland pools ; life cycle ; Trichoptera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Larvae of the caddisTrichostegia minor (Curtis) were collected from four woodland pools in The Netherlands, three of which are temporary, from August 1986 till June 1987. Eggs and larvae of this species proved to be very well adapted to drought, freezing, strongly fluctuating pH and alkalinity levels and prolonged oxygen deficit. The life cycle ofT.minor in a small woodland marsh overgrown byCalla palustris took one year. Adult flight period started at the end of May. Oviposition took place independent of water. Hatching of the eggs started in September and was probably induced by immersion. During the larval stage from September until May, 5 instars could be distinguished by the size of the head capsule. Growth of instars I, II and III during autumn was moderate. Most larvae overwintered as instar III or IV. Possibly there was a larval diapause during winter. In spring rapid growth to instar V took place prior to pupation. Growth rate, expressed as the increase of mean individual dry weight was highest from March to April (2.05±0.75% DW.m−2.d−1). In extremely shallow water growth in spring was initially more rapid compared to growth in deeper water. During winter the growth rate decreased to 0.038±0.071% DW.m−2.d−1. Net annual production based on the changes of momentary biomass was 183.2±31.7 mg DW.m−2.y−1 or 177.2±31.3 mg AFDW.m−2.y−1. Production loss during the winter season was 75.1±10.8 mg DW.m−2.y−1 or 72.3±10.6 mg AFDW.m−2.y−1.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-5125
    Keywords: classification ; macro-invertebrates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An ecological classification of surface waters in the Netherlands is presented. This classification is based on literature data and the authors opinions concerning the habitat range of macroinvertebrate taxa. Water types were defined by key factors. Taxa were assigned to these water types and provided with a characterizing weight. The list may be a useful tool in the ecological management of waters.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1573-5125
    Keywords: Glossiphonia paludosa ; life cycle ; Hirudinea ; The Netherlands
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The widely distributed but rare leechGlossiphonia paludosa (Carena) was collected for the first time in The Netherlands in 1988 in a eutrophic ditch in the nature reserve ‘De Regulieren’ near Geldermalsen. The habitat is described briefly and, for the first time, the life cycle ofG. paludosa is presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Numerische Mathematik 36 (1980), S. 177-195 
    ISSN: 0945-3245
    Keywords: AMS (MOS): 65F15, 68C25 ; CR: 5.14, 5.25
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Summary A method is given for calculating the eigenvalues of a symmetric tridiagonal matrix. The method is shown to be stable and for a large class of matrices it is, asymptotically, faster by an order of magnitude than theQR method.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    facet.materialart.
    Unknown
    EIS-Nederland
    Publication Date: 2015-06-03
    Keywords: Kevers ; Coleoptera ; Graphoderus bilineatus ; gestreepte waterroofkever ; Nederland ; bescherming ; Habitatrichtlijn ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Part of book or chapter of book
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2015-06-03
    Description: Harmonia axyridis in the Netherlands: a gain for the fauna or an unwanted intruder (Coleoptera: Coccinellidae)? The coccinellid Harmonia axyridis (Pallas, 1773), a well-known aphid predator originating from Asia, was found for the first time in the Netherlands (Heilige Landstichting near Nijmegen) in 2002. During 2003, the species was collected at several localities in the southern part of the country. In the surroundings of Tilburg and Rotterdam the species is already considered as common. Its establishment could be the result of either survival of independently released (or escaped) specimens for biological control (very likely for the population in Rotterdam), or a colonisation from Belgium were outbreaks of H. axyridis were recorded in the preceding years (likely for the surroundings of Tilburg). Risks and regulations with respect to the introduction of exotic species as biological control agents of pests in indoor and outdoor cultures are discussed. Recently, regulations have been sharpened in the Netherlands, but they are too late to prevent the establishment of H. axyridis, wanted or not. Once an exotic species has established itself it is virtually impossible to get rid of it.
    Keywords: Coccinellidae ; Harmonia axyridis ; Herkenning, Biologie ; Nederland ; Verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 13 (1983), S. 0 
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SUMMARY. 1. Adult Hygrotus beetles were collected from about 400 localities out of 621 sampled in the Netherlands. Distribution of the three Dutch species of this genus has been related to different environmental variables, principally by use of the Index of Representation (I.R.).2. Hygrotus decoratus is an acidophilous and haloxenous species. It inhabits small water bodies such as peat-ditches, reed-lands and overgrown ditches where emergent plants are abundant. Hygrotus inaequalis occurs in all of the habitats studied and has no clear preferences or aversions with respect to the environmental variables examined. Hygrotus versicolor inhabits permanent water bodies such as clay- and sand-canals which have a rich growth of submerged plants and a weak current. The species has a significant preference for waters with a pH between 7.1 and 8.0 and a chlorinity between 60 and 200 mg 1-−1.3. H. decoratus and H. versicolor rarely co-exist because of their different environmental requirements, but both species often co-exist with H. inaequalis. Structural environmental variables such as water depth and abundance and growth-form of the aquatic plants play a greater role than chemical factors in habitat selection by Hygrotus spp.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...