. Coast watch. Marine resources; Oceanography; Coastal zone management; Coastal ecology. complaining that catches had declined and that red sore disease was on the rise. Many claimed that they had not seen red sores on fish until the early 1970s, when the algal blooms began. Surveys revealed red sore outbreaks from the Chowan River to the Scuppemong River, with the highest incidence in the Chowan. In 1976, an outbreak of the disease killed about 95 percent of the Albemarle Sound's white perch population. Research- ers determined that the sores were caused by Aeromonas hydrophila, a bacteria th
. Coast watch. Marine resources; Oceanography; Coastal zone management; Coastal ecology. complaining that catches had declined and that red sore disease was on the rise. Many claimed that they had not seen red sores on fish until the early 1970s, when the algal blooms began. Surveys revealed red sore outbreaks from the Chowan River to the Scuppemong River, with the highest incidence in the Chowan. In 1976, an outbreak of the disease killed about 95 percent of the Albemarle Sound's white perch population. Research- ers determined that the sores were caused by Aeromonas hydrophila, a bacteria that flourishes in polluted water. They sus- pected that environmental stress from the declining water quality in the Chowan River was contributing to the outbreaks. The only way to fight the disease was to improve water quality. A fertilizer plant near Tunis was implicated as a primary source of nutrients contributing to the algal bloom problem in the Chowan River. As many as 4,000 pounds of nitrogen were being discharged from the plant into the river each day. Research also strongly implicated farming practices and changes in drainage and forest cover as contributors to the problem. Researchers from the University of North Carolina at Chapel Hill noted that though there had been a decrease in farmland in the river basin since 1950, the yields for all major crops had risen due to mechanization and increased fertilizer usage. This study also documented that 67 percent of the North Carolina farmland in the Chowan River had been ditched for drainage to the river, compared to only 6 percent of Virginia farmland. In addition, there was a 30 percent decrease in wet- lands forested with oak, gum and cypress in the North Carolina portion of the basin between 1964 and 1974. These changes in land use are signifi- cant to nutrient loading. Increased fertilizer use creates a greater potential for excess nutrient runoff. Ditching and draining of cropland decreases the travel time of water mo
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Keywords: ., bookcentury1900, bookcollectionunclibra, booksubjectoceanography
