abstract this paper presents a quantitative account of vegetation–environmental factor relationships in arid rangelands. vegetation cover was recorded using braun-blanquet combined abundance-cover scale in each quadrat. within each quadrat, one profile was dug and soil samples being taken at 0-20cm and 20-100cm depths. under study physical-chemical characteristics included texture, lime, organi...

the distribution of macroinvertebrate communities from 5 sampling sites of the tajan river were used to examine the relationship among physiochemical parameters with macroinvertebrate communities and also to assess ecological classification system as a tool for the management and conservation purposes. the amount of variation explained in macroinvertebrate taxa composition is within values repo...

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...

Macroinvertebrate communities and environmental variables were assessed seasonally for 1 year in a temporary river in South Portugal receiving an effluent with high conductivity, pH, sulphates, nitrates and low oxygen content. The usefulness of the ordination method canonical correspondence analysis (CCA) and the classification method cluster analysis (UPGMA) were examined to evaluate the pertu...

Canonical Correspondence Analysis (CCA) is quickly becoming the most widely used gradient analysis technique in ecology. The CCA algorithm is based upon Correspondence Analysis (CA), an indirect gradient analysis (ordination) technique. CA and a related ordination technique, Detrended Correspondence Analysis, have been criticized for a number of reasons. To test whether CCA suffers from the sam...

the aim of this study was to investigate relationships between soil properties and plant species to determine the most effective factors separating vegetation communities in rineh rangeland. three stratifying variables were selected including slop, aspect and elevation. the study area was partitioned by combining these classes to generate homogenous units. 1m2 quadrates were located at sampling...

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...

The aim of this study was to investigate relationships between soil properties and plant species to determine the most effective factors separating vegetation communities in Rineh rangeland. Three stratifying variables were selected including slop, aspect and elevation. The study area was partitioned by combining these classes to generate homogenous units. 1m2 quadrates were located at sampling...

The integration between vegetation data, human disturbance factors, and geo-spatial data (Digital Elevation Model (DEM) and image data) is a particular challenge for vegetation mapping in mountainous areas. The present study aimed to incorporate the relationships between species distribution (or vegetation spatial distribution pattern) and topography and human disturbance factors with remote se...

The assessment of Burkholderia diversity in agricultural areas is important considering the potential use of this genus for agronomic and environmental applications. Therefore, the aim of this work was to ascertain how plant species and land use management drive the diversity of the genus Burkholderia. In a greenhouse experiment, different crops, i.e., maize, oat, barley, and grass, were plante...