Kurzidim, M. (1995). Lausbub im Internet – WWW-Server für Windows 3.1.
Schlüsselwörter: internet, e-mail, www, software, Grundlage
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Otto, T. (1994). Auf zufälligen Wegen zum Ziel.
Schlüsselwörter: Simulation, Methode, Mathematik, Pascal, Listing, Algorithmus
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Fore, L. S., Karr, J. R., & Conquest, L. L. (1994). Statistical properties of an index of biological integrity used to evaluate water resources (Vol. 51).
Zusammenfassung: The authors determined the statistical properties of the index of biotic integrity (IBI) from electrofishing samples collected from Ohio streams. Although IBI is widely used to evaluate the condition of water resources by biologists and resource managers, expanding its role as a regulatory tool depends on statistical validation of its precision and power. We addressed these issues by constructing an additive variance model for IBI and testing the assumptions of that model directly with a bootstrap resampling algorithm and simulations using field data. Statistical properties of IBI supported the use of standard analysis techniques such as ANOVA for hypothesis testing. We determined with power analysis that IBI can distinguish between five and six nonoverlapping categories of biotic integrity based on a model that includes the effects of measurement error, variability of fish assemblages through time, and statistical interaction of location and time.
Schlüsselwörter: Umweltverschmutzung, Fisch, Elektrofischerei, Methode, Mathematik, Modell, Statistik, ANOVA
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Swain, D. P., & Sinclair, A. F. (1994). Fish distribution and catchability: What is the appropriate measure of distribution? (Vol. 51).
Zusammenfassung: The authors show that spatially uniform changes in abundance can affect catchability given certain models for the distribution of fishing effort, but that this effect is slight compared with the effect of changes in the spatial spread of fish distribution. An index of distribution is described that depends only on spatial spread: the minimum area over which a specified percentage of the population is spread. We tested the density dependence of this index using data on Atlantic cod (Gadus morhua) in the southern Gulf of St. Lawrence. Results depended on the percentage of the population for which the index was evaluated. The area containing most (90 or 95%) of the population was density dependent, expanding as population size increased. The area of highest cod concentration (i.e., the area containing 50% of the population) did not expand significantly as population size increased.
Schlüsselwörter: Fisch, Statistik, Population, Fischerei, Geographisch, Mathematik, Modell
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Angermeier, P. L., & Smogor, R. A. (1995). Estimating number of species and relative abundances in stream-fish communities: Effects of sampling effort and discontinuous spatial distributions (Vol. 52).
Zusammenfassung: The authors sampled fishes and measured microhabitat in series of contiguous habitat units (riffles, runs, pools) in three Virginia streams. Monte Carlo simulations were used to construct hypothetical series of habitat units, then examined how number of species, similarity in relative abundances, and number of microhabitats accumulated with increasing number of habitat units (i.e., sampling effort). The curves indicated that 90% of the species present were usually found by sampling 5 to 14 habitat units (stream length of 22-67 stream widths). Estimates of species relative abundances required less sampling effort for a given accuracy than estimates of number of species. Rates of species accumulation (with effort) varied among streams and reflected discontinuity in species distributions among habitat units. Most discontinuity seemed to be due to low population density rather than to habitat selectivity. Results from an Illinois stream corroborated our findings from Virginia, and suggested that greater sampling effort is needed to characterize fish community structure in more homogeneous stream reaches.
Schlüsselwörter: Fisch, Fließgewässer, Habitat, Verbreitung
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Poschwitz, H. (2005). Die Bewertung von Fließgewässern nach der Europäischen Wasserrahmenrichtlinie (EG-WRRL) (Vol. 94).
Schlüsselwörter: Fisch, WRRL, Methode
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Steinmann, P. (1949). Gründe für das verschiedene Aussehen frischgeschlüpfter Felchenbrut (Vol. 56).
Schlüsselwörter: Fisch, Felchen, Coregonus, Larven, Morphologie
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Hinrichs, D. Der Einfluss der Gewässerunterhaltung auf die Fischfauna von Meliorationsgräben (Vol. 50).
Schlüsselwörter: Fisch, Fauna, Gewässerunterhaltung, Meliorationsgraben
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Poschwitz, H. (2007). Die Fischfauna des staugeregelten Untermains zwischen 1850 und heute (Vol. 58).
Schlüsselwörter: Fisch, Vorkommen, Main, WRRL, historisch
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Poschwitz, H. (2008). Heimische Krebse: seltene Bewohner der Fließgewässer des Untermaingebietes. Fischer und Teichwirt, 59(5), 166?169.
Schlüsselwörter: Krebs, Verbreitung, Krebspest, Vorkommen, Gefährdung
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