Photo by Steve Murray 



Sea Grant researcher Don Stanley says 

 decomposition of dying algae and dino- 

 flagellates along the river bottom can rob 

 waters of needed oxygen. 



Couple the decomposition with no tur- 

 bulence from wind and wave action to mix 

 oxygen-rich surface waters with oxygen- 

 poor bottom waters and waters can again 

 become anoxic, Stanley says. 



But oxygen depletion isn't the only prob- 

 lem. Nuisance algae and dinoflagellates 

 aren't considered "tasty" by some fish and 

 shellfish. This taste discrepancy can alter 

 the food chain, leaving waters inhabited by 

 less desirable bottom fish. And the algae 

 and dinoflagellates can release toxins that 

 can kill fish and shellfish. 



And those are just the problems caused 

 by algal blooms. An abundance of nutrients 

 and poor water quality have also been 

 connected to fish and shellfish diseases. 



Sea Grant scientist Ed Noga has deter- 

 mined that ulcerative mycosis, a fish 

 disease that infects menhaden and other 

 fish, is directly linked to the stresses 

 caused in the fish by poor water quality 

 and nutrients. 



Since nutrients are clearly the "germs" 

 causing the Tar-Pamlico's ailment, the 



EMC placed restrictions on their input. 

 Phosphorus inputs into the basin are to be 

 decreased 64 percent. Most of the de- 

 crease will come when Texasgulf Inc. 

 lowers its input in 1992. Meanwhile, the 

 EMC required that nitrogen inputs drop by 

 10 percent. 



The DEM will work with industries and 

 waste treatment plants through discharge 

 permits to decrease nutrient output from 

 these sources. And farmers will be en- 

 couraged through the NC. Agricultural 

 Cost Share Program to implement Best 

 Management Practices in their barnyards 

 and fields. The BMPs include contour plow- 

 ing, terraces, crop rotation, grassed water- 

 ways and animal waste management. 



Although the nutrient-sensitive designa- 

 tion is a step in the right direction for the 

 Tar-Pamlico, Rader feels the restrictions 

 were not tough enough. 



"The state is waiting for results from the 

 Albemarle-Pamlico Estuarine Study to im- 

 plement tougher restrictions," Rader says. 

 "But I'm not sure the river can wait for 

 science. Virginia officials are planning to 

 reduce nitrogen and phosphorus levels in 

 the Chesapeake by 40 percent using seat- 

 of-the-pants science. That's the kind of thing 



I believe we need to do on the Pamlico." 



And Rader is concerned about nitrogen 

 input from acid rain. "EPA (Environmental 

 Protection Agency) estimates that by 2030, 

 emission of nitrogen (from combustion 

 engines in cars and trucks) into the air will 

 go up 60 percent in the Southeast," he 

 says. "If so, that will be a big change, and 

 the state needs to address that." 



As "doctors" to the ailing rivers, scientists 

 such as Paerl, Stanley and Noga are be- 

 ginning to diagnose the symptoms and of- 

 fer resource managers some remedies. And 

 they're broadening their examinations to 

 include the estuarine systems downstream. 



All of North Carolina's nutrient-sensitive 

 rivers empty into vital, productive estuaries 

 that serve as nurseries to 90 percent of the 

 state's commercially important species of 

 fish and shellfish. And in that flow of water 

 teems plenty of nutrients that are just 

 beginning to cause estuarine maladies. 



Paerl says he is seeing more salt-tolerant 

 algal blooms in estuaries. And the input of 

 nitrogen from acid rain may have an even 

 greater impact in estuaries and nearshore 

 waters than it does in our rivers, he says. 



But the prognosis is not all bad. 



"With good science and proper man- 

 agement, the nutrient problem can be 

 reversed," Paerl says. "But we have to start 

 now. The environment can't absorb any 

 more than we're putting in it presently." 



Photo by Allen Weiss 



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