Experimental Approaches to Sediment Communities
800
400
350
"'E 300
~ 250
' Of;
i!! 200
~ 150
§ 100
I:
50
cage control
1
10g
o I---'H---l--+-+38
54
~II
76
'108
152
215
304
430
610
860
1720 2400 3500
equivalent spherical diameter
347
Fig. 16.4. Body-size spectra of invertebrates in an undisturbed area (225 cm 2 ) of
intertidal mudflat, and in similar areas enriched with 10 and 30 g of Enteromorpha (see
text), Ythan estuary, Scotland. Solid bars on spectra show location of meio- and macrofaunal modes and arrows indicate locations of troughs, as defined by a kernel estimation
procedure. Spectra are the mean of five replicates per treatment. (Raffaelli et al. 2000)
16.4 Production and Biodiversity
Many factors determine species richness (biodiversity), but the supply of
useable energy has been increasingly proposed as a mechanism (e. g. Wright
et al. 1993; Hall 2000). However, the relationship between energy supply and
species richness is probably scale-dependent (Hall 2000). On a global scale,
richness increases monotonically with energy supply (Currie 1991), whilst on
regional scales (hundreds of kilometres), a hump-shaped relationship exists
between diversity and productivity, with the greatest diversity at intermediate