detrital fragments, respectively. Organic carbon was a decreasing proportion 

 of the dry weight of the three fractions on a dry weight basis; there was a 

 significant increase on an ash-free dry weight basis for the dead blades. 

 During senescence there was a loss of nitrogen from the leaves and an increase 

 in the nitrogen of the detritus relative to the dead leaves. The relative 

 proportions of nitrogen-acetyl-glucosamine, nitrogen and organic carbon were 

 all higher in the fall and winter. 



125. THAYER, G.W. , WOLFE, D.A. , and WILLIAMS, R.B., "The Impact of Man on Sea- 

 grass Ecosystems," Ameviaan Scientist, Vol. 63, 1975, pp. 288-296. 



This report discusses seagrasses, especially Zostera and Thalassia and 

 their distribution, environmental tolerances, and productivity. Coastal 

 development, including dredging and pollution, can destroy seagrass beds by 

 reducing light penetration, changing the redox potential of anerobic soils, or 

 by adding toxins to the seagrass ecosystem. Other environmental disturbances 

 are crude oil spillage, heated water discharge, and commercial fishing. The 

 destruction of seagrass beds can have far-reaching impacts on organisms 

 dependent on the grasses and detritus. 



126. THOMAS, L.D. , MOORE, D.R. , and WORK, R.C., "Effects of the Hurricane 

 Donna on the Turtle Grass Beds of Biscayne Bay, Florida," Bulletin of 

 Marine Science, Vol. 11, No. 2, June 1961, pp. 191-197. 



The dry and wet weight of Thalassia testudinum washed ashore at Biscayne 

 Bay during Hurricane Donna in 1960 is estimated. Agents destructive to 

 turtlegrass (other than wind) are discussed, and additional observations are 

 included of hurricane damage to the turtlegrass beds of the Bahama banks. 



127. THOMAS, M.L.H., and DUFFY, J.R., "Butoxyethanol Ester of 2, 4-D in the 

 Control of Eelgrass {Zosteva marina L. ) and its Effects on Oysters 

 (Crassostrea virginica gmelin) and other Benthos," Proceedings of the 

 Northeastern Weed Control Conference, Vol. 22, 1968, pp. 168-194. ^ 



Eelgrass {Zostera marina) growth has a detrimental effect on oyster farm- 

 ing in eastern Canada. Results of preliminary experiments in chemical and 

 mechanical control of eelgrass showed that mechanical control attempts by 

 cutting or digging were short-lived, expensive, and frequently a failure. In 

 earlier trials with various herbicides, only one was effective at reasonable 

 concentrations without causing unacceptable mortalities of associated biota. 

 This was a granular formulation of the butoxyethanol ester of 2N 4-D. Liter- 

 ature indicates that concentrations found in the field are not expected to 

 harm animals. 



128. THORHAUG, A., "Transplantation of the Seagrass Thalassia testudinum 

 Konig," Aquaculture, Vol. 4, 1974, pp. 177-183. 



The article covers gathering seed pods of turtlegrass, and preparing and 

 planting the seeds. Laboratory seeding resulted in poor plant survival and 

 near failure. However, field trials in Biscayne Bay, Florida, were successful 

 with approximately 70-percent survival of seedlings 8 months after planting. 



129. THORHAUG, A., "Transplantation Techniques for the Seagrass Thalassia 

 testudinum," Sea Grant, Technical Bulletin No. 34, University of Miami, 

 Miami, Fla., June 1976. 



Turtlegrass {Thalassia testudinum) can be planted throughout the Gulf of 

 Mexico, southeast Florida coast, and the Caribbean. Two planting methods, 



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