Constrained ordination methods include constrained (or canonical) correspondence analysis (CCA), redundancy analysis (RDA) and distancebased redundancy analysis (db-RDA). Constraining means that ordination only shows the community variation that can be explained by external environmental variables or constraints. This document describes the following basic concepts (1) usage of constrained ordi...

This paper presents the R package anacor for the computation of simple and canonical correspondence analysis with missing values. The canonical correspondence analysis is specified in a rather general way by imposing covariates on the rows and/or the columns of the two-dimensional frequency table. The package allows for scaling methods such as standard, Benzécri, centroid, and Goodman scaling. ...

This study describes the current status of the small fish community in Niushan Lake in China, and examines the spatial and seasonal variations of the community in relation to key environmental factors. Based on macrophyte cover conditions, the lake was divided into three major habitat types: (1) Potamogeton maackianus habitat, (2) Potamogeton maackianus and Myriophyllum spicatum habitat, and (3...

Multi-scale investigations of species /environment relationships are an important tool in ecological research. The scale at which independent and dependent variables are measured, and how they are coded for analysis, can strongly influence the relationships that are discovered. However, little is known about how the coding of the dependent variable set influences community-level analyses. In th...

Canonical correspondence analysis (CCA) is perhaps the most popular multivariate technique used by environmental ecologists for constrained ordination; it is an approximation to the maximum likelihood solution of the Gaussian response model. In this article, we look at the constrained ordination problem from a slightly different point of view and argue that it is this particular point of view t...

Along the paper the new method called Invertebrate Bankfull Assessment method (IBA method) of determination of bankfull discharge is presented. The investigation of bankfull discharge using IBA were performed within one Polish Carpathian stream in the mountain region: the Ochotnica Stream. As an index of bankfull the existence of certain species of invertebrates was used which are present and r...

Natural habitats surrounding agricultural Þelds provide a source of natural enemies to assist in pest control. The boundaries among landscape elements Þlter some organisms attempting to cross them, resulting in differing communities within the landscape elements. Ground beetles are numerous and generally disperse by walking. These qualities make them excellent organisms for the study of boundar...