The bar charts below illustrate the
distribution of individual plant species along the East/West Belt Transect. The red bars
represent the % cover of the plant species in each 1m quadrat along the line. This shows
where each species occurred on the line, as well as how much of it there was at each
point. The vertical scale is the same for each bar chart. The blue bars in the charts
represent the water depth, with maximum depth being 65cm.
These bar charts can be directly related to the plant zonation diagrams produced as part of the line transect
results. The species colours are co-ordinated between the diagrams and these charts.
Comparison of the two illustrates the difference in the type of results obtained using
line and belt transect methods.
Most species will have an optimum zone within their
range where the environmental conditions are best suited to their growth. In the diagrams
below, this zone will be indicated by the area where the species reaches its maximum %
cover. The percentage cover will often tail off gradually to either side of the optimum
zone.
The optimum zone for Bog Bean is clearly in the deepest
water areas. Reedmace and Branched Bur-reed both occupy a wide range across the centre of
the transect where the water levels vary, but are fairly shallow. Branched Bur-reed is
more dominant (the red bars are taller).
Silver Birch and Alder are found in the drier areas on
either side of the transect, while Willow also extends into the wetter marsh areas.
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