171 
The salt marsh system is extremely productive and it compares 
favorably with agricultural areas. The results of chemical analysis of 
plant materials varies with species, but all of the plants produce 
protein, fat, carbohydrates, and vitamins in substantial amounts. On 
the basis of dry weight of material produced, the marshes surpass 
most agricultural lands, including intensely farmed areas of developed 
countries, (fig. III). It must be noted that this high production is 
realized without any effort by man and that this production is available 
to be utilized by man. 
_ It should also be noted that this productive system 1s a self sustain- 
ing one and does not need to be constantly and artificially maintained 
as does an agricultural system. The utilization of the very high salt 
marsh production is especially interesting because in this system, 
unlike most others, production gets ahead of in sito consumption and 
there is an excess of energy-bearing material. This material can be 
stored for later use or can be exported, and it is the export of material 
from the salt marsh to the estuary that makes the system so important. 
The salt marsh production is utilized in two ways. First, and least 
important, is direct consumption of fresh plant material by herbivores 
and plant parasites. This path way accounts for about 5 percent of the 
total crop. The second type of consumption is that of detritus feeders 
(crabs, snails, mollusks, worms), who utilize the material after it has 
been broken down by bacteria and fungi. Decomposition of marsh 
grass and algae occurs in the gut of plant grazers, and the residue is 
available to other organisms in the form of feces. Decomposition of the 
actual plant by bacterial action begins with the rupture of cell mem- 
branes and subsequent release of cell components to the environment. 
Fresh detritus is especially nutritive for detritus feeders because it 
still contains protoplasmic material and adhering bacteria which are 
easily digested. Older detritus contains relatively more carbohydrate 
and less protein, but because decomposition is a continuing process 
there is usually a mixture of both old and new on the surface of the 
salt marsh. 
Grams of organic material per meter * per year 
iene Levers shes Oe) eer ere Eel yh, lhe he oP urepe er yeet ee Qeey seer ee 2, 000 
@eccanhiContimental/Shelf_ oe win: pack inj) aes) seep ee fedee ea See RE 300 
Casa. Cpe. ae ae 2S a SRS a Pee Pee Sa: 222 100 
MinearmeenjOrldl average -- 8-222 ee 340 
umeciieenmesenontnm yields “A. mee ON AIS ee ee ee oe 1, 400 
Fieure III.—Table showing annual production (dry weight) of marsh land, 
oceanic areas, and agricultural land. 
spiders 
Spartina ——-———> Herbivorous Insects ————————» sparrows 
(chewers and suckers) dragon flies 
Aleae / 
i 
\ Bacteria 
pe am 
Mud Dwellers PEERS. 5 aE y= Secondary Consumers 
(feed on detritus and dead vegetion) raccoons, rails, etce) 
Fig. IV: diagrammatic representation of the flow of energy-bearing 
materials through the salt marsh system. (after Teal), 
57-242—_71—_—_12 
