Canonical Correspondence Analysis (CCA),
Redundancy Analysis (RDA)
Multiple Regression (MR).
Stepwise Regression (SR)
Researchers in other fields such as palaeontology, archaeology and the social sciences
also use many of these methods.
A particular feature of ECOM is the graphical output that enables you to quickly
visualise the complex relationships within your data set. For example, CCA output
includes plots of sample and species ordinations, environmental correlation vectors
and biplots of species arranged along individual environmental axes. All aspects of the
graphs can be altered, and printed or exported in a wide variety of formats.
The user supplies two input data sets, in a 2 D array, holding the biological and
physical data for the samples (sites) respectively. In ecology, it is usual for the
samples, which are normally collected from set localities and may be called, for
example, quadrates or stations, to form the columns. The variables for each sample
are the rows and in the case of the biological data comprise the numbers of each
species or other taxon observed.
The environmental data may be either continuous variables such as pH, temperature
or current speed; or binary variables such as soil or treatment type, which are scored
as either a 0 or 1. ECOM complements CAP (Community Analysis Package) and
Species Diversity and Richness II (SDR) which offer a range of techniques that
only require biological data to undertake the analysis.
Species Diversity and Richness II
Home page link
A program to calculate and compare species diversity, estimate total species richness
and study patterns of abundance
Species diversity and richness
is a Windows 95/98 program designed for both the
professional ecologist and students. The methods on offer range from the familiar,
such as the calculation of various diversity indices and the fitting of common
distributions to more recently developed techniques such diversity ordering and total
species richness estimators. Together they provide a powerful suite of methods to
explore, compare and analyse community diversity. Species diversity and richness
version 2 offers considerable improvements over version 1. Existing users will
immediately note the redesigned menu system and improved graphics, data input and
printing. Probably the greatest recent improvements have been the extended range of
methods and statistical tests on offer. The program offers all the analytical tools that
a general ecologist needs for analysing and comparing the diversity of communities.
Because most users have now moved to Windows 95/98 version 2 is not available for
Windows 3.1. Version 1 of the program is supplied for 3.1 users.
Methods available within Species diversity and richness include
9 Alpha diversity indices including Shannon s, Simpson s, Fisher s and Q statistic.
Bootstrapping of confidence intervals.
Randomization tests to compare diversity between sites.
2 diversity ordering methods.
6 methods to estimate total species richness
Rank order and species accumulation curves.
Copyright 2004 PISCES Conservation Ltd