CURRENT LITERATURE 



BOOK REVIEWS 



Ecology of tide lands 



There is no place more suitable for the study of dynamic ecology than in 

 areas swept over by the tides, and there is no one better able to write on the 

 problems of such areas than Professor Oliver. 1 For years he and his stu- 

 dents have attacked seashore problems, first on the coast of Brittany, and 

 more recently on the coast of Norfolk. The Bouche d'Erquy and Blakeney 

 are household words to all students of shore ecology. The main results of 

 Oliver's studies are now incorporated in book form, and, quite in the spirit of 

 the time, he has become associated with an engineer, who presents the practical 

 application of ecological principles to engineering problems along shore; the 

 result is a masterpiece of applied ecology. 



The first chapters deal with tide and current data, the tidal compart- 

 ments of rivers, and the foreshore. That the problem is one of no mean 

 importance is shown by the fact that in the British Isles there are 8000 miles 

 of shore line and 11,000 miles of river front at high water; and there are 

 1250 square miles of area between tides. Oliver's greatest contribution is 

 in chapters iv-vii, which deal with the function of vegetation, sand dunes 

 and their fixation, and shingle beaches and their fixation. The fundamental 

 importance of plants in the stabilization of shore lines has been inadequately 

 realized by engineers, although sporadic and often ineffectual planting of sand 

 dunes has been more or less indulged in for a century. A perusal of this work 

 makes it clear that ecology must form a large part of the education of an 

 engineer who really wishes to get at the foundations of shore problems. So 

 far as dunes are concerned, Britain's problem is not as great as that of Gascony 

 and other continental tracts. The most satisfactory plant for dune fixation 

 is Psamma (Ammophila), although Elymus arenarius, Car ex arenaria, and 

 other species may also be used. Even lichens and mosses have a fixative 

 value. The chief factor in dune fixation lies in the development of an effec- 

 tive foredune. 



One of the striking features of British shores is the shingle beach, where 

 cobblestones are piled up by vigorous wave movement. At Dungeness the 

 shingle covers 10,000 acres. At Blakeney on the Norfolk coast the shingle is 

 piled up to a height of 10 feet above high water, and at Chesil on the Atlantic 

 shore, the height is 30 feet. Shingle is kept mobile (1) by wave impact and 



^— ■■— 1 — t 



1 Carey, A. E., and Oliver, F. W., Tidal lands; a study of shore problems. 

 8vo. pp. 284. pis. 29. figs. 54. London: Blackie & Son. 1918. 



35o 



