no fresh water coming in at all. If there is a fresh water table 

 it is lying in the dunes. Now what happens is you get your 

 Juncus maritimus zone lying up against the dunes. There is 

 no possibility of that Juncus maritimus zone going into any- 

 thing else at all. It represents the final climax on the marshes 

 simply because physiographically there is no fresh water and 

 it cannot go any further. For that reason I call it a physio- 

 graphic climax or a sere climax. It is not the true climax 

 because if you get on to the mainland where there is fresh 

 water coming in you know it is going to go somewhere else. 

 I think if you use Weaver and Clements terminology it would 

 become the free climax if you want to use that. I think, for 

 convenience' sake, I would simply call it the sere climax. 



Odum: 



Is there evidence indicating which of these associations go 

 toward increasing organic matter or increasing soil and up 

 into something else other than marsh where the sea level is 

 constant? Is it certain, for example, that there is always a 

 succession in some kinds of these types as opposed to others, 

 succession away from marsh into something of a more ter- 

 restrial type ? 



Chapman: Well I think if sea level is constant and no fresh water is com- 



ing down, all that happens is that the community is going to 

 lie adjacent to an entirely different community, a sand dune 

 community if you like, or it is going to lie adjacent to a 

 meadow. 



Odum: It does not accumulate then? 



Chapman: No, it does not because unless there is a change of sea level 



there is no possible means of its accumulating. 



Redfield: Suppose you have an accumulation of silt so that the surface 



built up and you got shorter tidal exposure. 



Chapman: I see what you mean Dr. Redfield. I think the only thing is 



what Dr. Odum has mentioned. Now you would have to get an 

 accumulation of peat. In other words your final plant would 

 have to be a peat former to get any further innovation because 

 the only way in which you can get the accumulation of organic 

 matter would be by decay of the actual plant remains, because 

 if your tide does not come over the area you cannot get any 

 further accretion of silt simply by a tidal phenomenon. Sim- 

 ilarly unless you have fresh water coming down you could not 

 get any accumulation of silt from the fresh water source, so 

 the accumulation of peat would be the only way that you could 

 get anywhere. In a case like that you would have the picture 

 that you find at the head of the Bay of Fundy marshes where 



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