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311.
312.
313.
Rainer Brüggemann Andreas Kaune Joachim Klein Reinhard Zellner 《Environmental Sciences Europe》1996,8(2):89-96
Using four dynamic criteria, the following environmental changes were evaluated: Global warming; destruction, of the stratospheric ozone layer; eutrophication and acidification of aquatic ecosystems; photochemical smog; reduction of the available area of agricultural soils; loss of species diversity; consumption of resources; reduction of crop yield; forest decline; noise, and smell. These ecosystem changes, or negative effects, were characterized by four dynamic criteria: 1) Regional importance, 2) extent of alteration, 3) resilience and 4) irreversibility. A multi-criteria assessment, accounting simultaneously for all four criteria, requires a generalized concept of order. Here, the concept of partially ordered sets, visualized by Hasse diagrams, was used to derive a priority list of environmental changes. Highest priority was equally assigned to the loss of species diversity, the consumption of resources and the destruction of the ozone layer. However, these ecosystem changes are incomparable to each other concerning the four criteria used and thus require different management strategies. 相似文献
314.
Joachim G. Frommen Marion Mehlis Christina Brendler Theo C. M. Bakker 《Behavioral ecology and sociobiology》2007,61(4):533-539
Shoaling with familiar kin is a well-known phenomenon. It has been described both for adult and for fry of three-spined sticklebacks
(Gasterosteus aculeatus). However, evidence of preference for kin independent of familiarity is scarce. Furthermore, inbreeding effects have not
been studied for shoaling preferences and there is a lack of studies about changes in individuals’ ability to recognise kin
during different phases of life history. We gave inbred and outbred, nonreproductive sticklebacks of different age the choice
to shoal with a group of familiar siblings vs unfamiliar non-siblings and with unfamiliar siblings vs unfamiliar non-siblings.
Subadult sticklebacks preferred to shoal with familiar kin over unfamiliar non-kin, but inbred and outbred individuals had
similar preferences. When given the choice between unfamiliar siblings and unfamiliar non-sibs, adult outbred fish preferred
the shoal of kin, while inbred fish behaved indifferently. Body characteristics of the group such as body mass, standard length
and condition of its members did not significantly explain the shoaling preferences for kin. Thus, sticklebacks were capable
of recognising familiar and unfamiliar kin. The latter capability was lost by inbreeding. 相似文献
315.
316.
Gerrit Schüürmann Klaus-Dieter Wenzel Ludwig Weißflog Klaus Wienhold Eckhard Müller 《Environmental Sciences Europe》1994,6(5):265-270
The spatial variation of the immission patterns of Cr, Fe, Pb and V in the region Leipzig-Halle is dicussed in terms of similarities as well as dissimilarities. The representation by isopleths enables the identification of areas with high and low air pollution. The immission patterns can be used as criteria to select areas suitable for in-field testing so that possible effects on fauna und flora and xenobiotic fluxes can be studied at representative sites. The comparison with literature data yields a first characterization of the ecotoxic potential of the heavy-metal immission for the region. By the principal component analysis a comparative evaluation of the spatial structure of all element contents is performed, which leads to conclusions about emission sources and the physicochemical behaviour of the elements. 相似文献
317.
Robert J. Paxton Nicole Weißschuh Wolf Engels Klaus Hartfelder J. Javier G. Quezada-Euan 《Die Naturwissenschaften》1999,86(3):143-146
Queens of the large, pantropical and fully eusocial taxon Meliponinae (stingless bees) are generally considered to be singly
mated. We indirectly estimated queen mating frequency in two meliponids, Melipona beecheii and Scaptotrigona postica, by examining genotypes of workers at microsatellite DNA loci. Microsatellites were highly variable, providing suitable markers
with which to assign patrilinial origin of workers within colonies headed by single queens. Queen mating frequency varied
between 1 and 3 (M. beecheii) and 1 and 6 (S. postica), representing the first clear documentation of polyandry in the Meliponinae. Effective paternity frequency, m
e
, was lower, although above 2 for S. postica. Stingless bees may provide suitable subjects for the testing of recent inclusive fitness arguments describing intracolony
kin conflict in social Hymenoptera.
Received: 26 August 1998 / Accepted in revised form: 18 November 1998 相似文献
318.
319.
As part of the research project “information system for environmental chemicals” a factual databank on a testset of 68 chemicals was developed. The set-up of the databank is described and the analysis of the results is shown for benzo(k)fluoranthene using a graphical boxplot illustration. 相似文献
320.
Michael Neumann Joachim Baumeister Matthias Liess und Ralf Schulz 《Umweltwissenschaften und Schadstoff-Forschung》2003,15(3):152-156
Zusammenfassung Die Entwicklung, der Aufbau und die Evaluierung eines biologischen Indikatorsystems für die Pflanzenschutzmittel-Belastung
in kleinen Flie?gew?ssern wird vorgestellt. In Flie?gew?ssern mit landwirtschaftlichem Einzugsgebiet stuft das Expertensystem
LIMPACT die Belastung in vier Klassen ‘unbelastet/nicht nachgewiesen’, ‘gering’, ‘mittel’ und ‘hoch’ belastet ein. Eingangsdaten
sind dabei die Abundanzdaten der benthischen Makroinvertebraten-Fauna zu vier Terminen im Jahresverlauf (M?rz/April; Mai/Juni;
Juli/August; September/Oktober) und neun physikalisch-chemische bzw. morphologische Flie?gew?sserparameter. Die Wissenbasis
wurde mit dem Shellbaukasten D3 aufgebaut und enth?lt 921 Regeln zum etablieren oder de-etablieren einer Bewertungsklasse.
Es wurden 39 Arten und Taxa analysiert und dabei 13 positive und 24 negative Indikatorspezies definiert. Positive Indikatorarten
zeigen eine hohe Belastung durch hohe Abundanzen an, w?hrend negative Indikatorarten durch eine hohe Abundanz eine Belastung
ausschlie?en und unbelastete B?che anzeigen. Die Datenbasis enthielt 157 j?hrliche Untersuchungen und wurde auch zur Evaluierung
eingesetzt. Die korrekte Klassifikationsrate liegt bei 66,7–85,5% der F?lle. Die meisten verbleibenden F?llen werden nicht
falsch eingestuft, sondern infolge der konservativen Bewertung bei geringer Datengrundlage nicht klassifiziert.
Online First: 31.05.2002 相似文献