9780521861724htl 1..2

0

1

2

3

4

5

0

1

2

3

4

5

01230123012301230123

Trophic level

Trophic level

Log 10 Biomass (g m–2)

01230123012301230123

Figure 7.4Trophic pyramids from the five lakes with the fastest (upper) and slowest

(lower) turnover of primary producers (estimated as the proportion of the biomass that

was slow relative to fast turnover primary producers) across a gradient of increasing

intensity of top-down effects of fish (fish–invertebrates–periphyton–plants; Jones &

Sayer, 2003 ).

–0.5

–0.4

–0.3

–0.2

–0.1

0

0.1

0.2

0 0.2 0.4 0.6 0.8 1 1.2

Slope of Trophic Pyramid

Proportion of Biomass of Slow to Fast Turnover Primary

Producers

Square–Inverted

Triangular

Phytoplankton Macrophytes































 Figure 7.5Relationship

between slope of the

trophic pyramids in

17 lakes across a

gradient of increasing

intensity of top-down

effects of fish and the

proportion of biomass of

slow to fast turnover

primary producers.

y¼0.5104xþ0.196,

R^2 ¼0.387, p¼0.004.

130 J. I. JONES AND E. JEPPESEN