The Variation of the Condition of Sea-water, Especially the 



Hydrogen-ion Concentration, and Its Relation 



to Marine Organisms* 



Edwin B. Powers 

 University of Nebraska, Lincoln 



Contents Pago 



1. Introduction and methods 369 



2. Experimental data 371 



S. Hydrogen-ion concentration and oxygen content of 



surface sea-water 371 



4. Hydrogen-ion concentration and oxygen content of sea-water 



at different depths 374 



5. Hydrogen-ion concentration and oxygen content of surface 



sea-water, and their relation to tide 376 



6. Hydrogen-ion concentration of sea-water of a small lagoon 379 



7. Effect of vegetation and animal organisms upon hydrogen-ion 



concentration and oxygen content of sea-water 380 



8. Discussion 381 



9. Acknowledgments 383 



10. Bibliography 383 



1. Introduction and methods 



During the summers of 1918 and 1919 work was undertaken at the 

 Puget Sound Biological Station to determine the condition of the sea-water 

 in the vicinity of the station. Special attention was paid to the hydrogen- 

 ion concentration in relation to marine organisms. 



The colorimetric method of Sorensen (1909, 1909a) and Sorensen 

 and Palitzsch (1910, 1910a) was employed in all determinations of the 

 hydrogen-ion concentration of the sea-water. During the summer of 1918 

 the buffers and indicators as suggested by Clark and Lubs (1917) for 

 bacteriological work were used. It was with great difficulty that the 

 buffers were prepared at the station. Specially was this true of the 

 sodium hydroxide solution. To avoid any error due to a possible inac- 

 curacy in the stock solutions for the buffers each mixture was compared 



* Studies from The Department of Zoology, The University of Nebraska, 

 No. 127. 



(369) 



