Ordination of Zooplankton Community Data to Detect Pesticide Effects in Pond Enclosures

Abstract

Trends in community structure of crustacean zooplankton among 17 forest pond enclosures (5 m x 5 m x 1 m deep) were examined and analyzed to determine effects of two candidate forest pesticides. Eight enclosures were treated at two concentrations of an experimental insecticide, tebufenozide; five were treated at two concentrations of a biological herbicide, bialaphos; and four served as controls. Zooplankton community structure was characterized by ordination of species assemblages using principle components analysis (PCA) and correspondence analysis (CA). Two-dimensional plots of the first two axes from PCA and CA were constructed to explore temporal and treatment-related patterns in community structure. The first four axes of both ordination functions were used as multivariate descriptors of community structure and were examined for differences among treatments by ANOVA. Species ordination plots and sorted rotated factor loadings provided objective means of identifying the species important in determining divergence in community structure. These were considered indicator species and were examined for differences among treatments by ANOVA and specified contrasts. The ordination and subsequent analysis revealed trends in community structure and sample differences that indicated clear, concentration-dependent effects of bialaphos and equivocal effects of tebufenozide.

Tebufenozide has limited direct effects on simulated aquatic communities

“…The communities we established in the mesocosms are therefore representative of those in the area, but were missing some potential species. Our results are comparable to previous work that found no effect exposure to Tebufenozide on zooplankton communities (Kreutzweiser et al 1998 ; Kreutzweiser and Faber 1999 ).…”

“…A significant amount of prior work investigating non-target effects found no treatment effects at environmentally realistic exposures on zooplankton communities (Kreutzweiser et al 1998 ; Kreutzweiser and Faber 1999 ), phytoplankton abundance (Kreutzweiser and Thomas 1995 ), macroinvertebrates (Kreutzweiser et al 1994 ), aquatic arthropods (Song et al 1997 ) amphibian embryo hatching (Pauli et al 1999 ), and soil invertebrates (Addison 1996 ). The hormone, 20-hydroxyecdysone, which Tebufenozide mimics, or hormones of similar structure are produced by a variety of insect taxa (Smagghe and Degheele 1994 ; Hahn et al 2001 ).…”

Discriminant analysis of biogeochemical indicators of nutrient enrichment in a Florida wetland

“…The analysis of combinations of biological and chemical characteristics requires multivariate methods. A well-known and much used multivariate technique to examine and compare the structure of biological communities is principal component analysis (PCA; Kreutzweiser & Faber, 1999). Principal components are linear combinations of the original variables that maximize the variation represented in as few orthogonal factors as possible.…”

An optical biosensing film for biochemical oxygen demand determination in seawater with an automatic flow sampling system

“…Ru(ph 2 phen) 3 (ClO 4 ) 2 [ph 2 phen = 4,7-diphenyl-1,10-phenanthroline], used as an oxygen-sensing indicator, was synthesized and purified in the laboratory of the Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University. Glucose/glutamate (GGA) solution was prepared by adding 0.0750 g glucose and 0.0750 g L-glutamic acid to 100 ml phosphate buffer solution (pH 7.8), and this was used as the standard BOD solution (1000 ± 185 mg l −1 ) [22]. All other chemicals were of analytical grade without further purification and distilled water was used throughout.…”