Hj. Read et al., INVERTEBRATES IN WOODLANDS POLLUTED BY HEAVY-METALS - AN EVALUATION USING CANONICAL CORRESPONDENCE-ANALYSIS, Water, air and soil pollution, 106(1-2), 1998, pp. 17-42
Ground running invertebrates were sampled by pitfall trapping in woodl
ands with high and low aerial pollution by heavy metals. Principal com
ponent analysis calculated for the environmental variables showed degr
ee of metal contamination to be the most important difference between
the sites. Calculation of canonical correspondence analysis (CCA) for
different groups of animals e.g. Diplopoda, Opiliones, Aranaea and Car
abidae was carried out and produced plots which can be interpreted wit
h respect to the pollution effect. The effect of different environment
al factors on individual species or subgroups delimited by size, breed
ing season, diet etc. was determined. Species associating with or disa
ssociating from high pollution levels can be identified. No clear patt
erns were shown when examining size or breeding season in Carabids in
relation to pollution. The highly polluted woods near the main polluti
on source at Avonmouth are lacking in lycosid spiders, the vacant nich
e may be filled by a large species of ground running agelenid which ma
y be more adaptable in habits than the lycosids. CCA plots of both Ara
naea and all species pooled together show a triangular shape. This is
interpreted as representing a small number of species able to adapt to
high pollution levels and a larger potential number found at 'clean'
sites.