Vegetation and habitat data from the individual sites indicate that soil 

 moisture is the limiting factor for both past and present plant growth. Deposi- 

 tion of spoil on the canal banks has led to less uniform and more dynamic condi- 

 tions of soil moisture and has increased the range of soil moisture potentials. 

 These effects are observable in the vegetation pattern. Alternatives for the 

 placement and management of spoil materials are presented that allow some 

 control over the distribution and composition of vegetation. 



185. VENKATARAMIAH, A., LASKSMI , G.J. , and GUNTER, G., "Studies on the Effects 

 of Salinity and Temperature on the Commercial Shrimp, Penaeus azteaus 

 Ives, with Special Regard to Survival Limits, Growth, Oxygen Consumption 

 and Ionic Regulation," Report H-74-2, Office of the Chief of Engineers, 

 U.S. Army, Corps of Engineers, Washington, D.C., 1974. 



The distribution and abundance of most commercial and sports marine 

 fisheries species of the Middle Atlantic to Gulf Coast States are dependent on 

 estuarine areas. Some species such as the oyster Crassostrea virginica and 

 the clam Rangia ouneata spend their entire lives in the estuaries, while 

 several motile species use this habitat as a nursery ground. Species living 

 in low salinities avoid many enemies, parasites, and predators that do not 

 invade low salinity waters. The low salinity estuaries are essential to many 

 species, and they are certainly conducive to the normal development of the 

 young stages. It was observed that low salinity waters were essential for 

 the faster growth and better survival of young brown shrimp. The juvenile 

 shrimp in their estuarin° life stage require low salinity and warm waters for 

 normal growth and survival, rather than high salinity and low temperature. 



186. VENKATARAMIAH, A., et al . , "Studies on the Time Course of Salinity and 

 Temperature Adaptation in the Commercial Brown Shrimp Penaeus aztecus 

 Ives," Report H-77-1, Office of the Chief of Engineers, U.S. Army, Corps 

 of Engineers, Washington, D.C., 1977. 



The period of time it takes brown shrimp, Penaeus azteaus, to adapt to 

 changes in salinity and temperature was determined by analyses of certain 

 behavioral and physiological responses, respiratory rates, and osmotic and 

 ionic regulation. In brown shrimp, salinity and temperature requirements are 

 shown to be size-dependent. The optima for subadult shrimp (95-millimeter mean 

 length) seem to exist above 10 parts per thousand, preferably between 15 and 

 25 parts per thousand, and below 25° Celsius. In contrast the juveniles (70- 

 millimeter mean length) in previous studies have shown preferences for salinities 

 lower than 17 parts per thousand and for temperatures slightly higher than 26° 

 Celsius. The possible existence of seasonal salinity and temperature optimal 

 rhythms is discussed in relation to the life cycle of brown shrimp. 



187. VITTOR, B.A., "Effects of Channel Dredging on Biota of a Shallow Alabama 

 Estuary," Journal of Marine Science, Vol. 2, No. 3, Sept., 1974, pp. 111- 

 134. 



Channel dredging had temporary and localized direct effects on turbidity 

 in D' Olive Bay. It had no effect on water temperature, dissolved oxygen, sa- 

 linity, or circulation. A late summer dike break caused a 2.8-hectare mudflow, 

 which significantly reduced primary productivity of pelagic algae, and destroyed 

 most submerged vegetation and benthic fauna. These effects persisted for at 

 least 8 months after the accident occurred. Most benthic animals in the channel 



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