Community Ecology Processes, Models, and Applications

(a)

Small starfish

(Leptasterias)

Snails

(Nucella)

Birds

(Larus, Haematopus, Corvus)

Goose

barnacles

(Pollicipes)

Acorn 0

barnacles

(Semibalanus)

Mussels

(Mytilus)

− − −− −

−

−

− −

−

+

+ + +

−

+ +

+ +

(b)

644

4534

100103 106

kc/m^2 /yr

3890

0.6%

28175

1620

180

3890

224

81

Spiders

Recycling

Bact.

27995

Spartina

Photo.

Mech.

Photo.

Mech.

Resp.

Mech.

Resp.

Mech.

Algae

53

23

28

5

59

(^9031)
25
Mud Crabs
6
372
3671
Crabs
Nemas
Insects
462
305
6585
6280
600000
1800
34580
4010
32709
5.4%
563620
93.9%
Net
Export
(c)
Figure 1.1Examples of three kinds of ecological networks. (a) A food web for a portion of the grassland community near
Silwood Park, UK. Reprinted with permission from http://www.foodwebs.org using data from Dawahet al.(1995). (b) An
interaction network showing the signs of interactions among a subset of species in a community from the rocky intertidal
zone of the Pacific Coast of northwestern USA. Reprinted from Wootton (1994), with permission of the Ecological
Society of America. (c) A network of energy flow from a salt marsh in southeastern USA. Reprinted from Teal (1962),
with permission of the Ecological Society of America.
8 SHAPE AND STRUCTURE