The benthic ecology and community structure in Lyttelton Harbour ...

60.
mud and mudd~
regions and basically may be considererl
to include the continuum that was suggested by the
results of FaCJer~
The fourth group,
..
119 7 falls into the sandy
Purau Bay mouth_
recurrent groups analysis.
123, i25, j21? i22, j19, and.
on 1D the vicinity of
The generalized Mahalanobis D-square was
23525.7~ Dixon (1964) states that th value may be used
as chi-square under assumption of normality with m(g-l)
degrees of freedom.
In this content m represents the
number of variables and 9 the number of groups formed
from the variableso
value with 120 degrees of freedom ~s
In the present study th9 chi-square
very highly
significant. This may be interpreted as indicating
that there very little probabi ty that the groups ilS
indicated could have been formed by chance and that
the separation between them is complete and very large.
Discriminant analys
was used to formulate
~ groups 0 When each of the discriminant equations J
(se~
Table 3), evolved in the computation was applied to
coefficients d~~ived by consideration all of the
available parameters each site a, set of discriminC1nt
values was producede There ar~ four sets of
d
criminant values, that is, four values for each site.
The separation of the groups may be checked
visually by graphing
against one anothero
discriminant values as funct16ns
Fig 18. shows the separation
achieved by graphing functions 1 and 2 and Fig 19
shows the result of the graphing of functions 3 and 4.
At first glance three groups stand out as clearly
differentiated with the fourth rather indis
nctly
separated. Considering both graphs there is clearly a