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ecosystems, such as erosion rates, harbor usage, salt marsh bed loss, 

 and drift algae accumulation will be documented as well. 



One difficulty of using previous aerial surveys in this study was 

 that the imagery was not taken with submerged features in mind, and 

 field conditions were often unconducive to analysis. It is advisable 

 that any town or agency conducting an aerial survey of the coastal zone, 

 do so using the guidelines in Table 1. Routine vertical aerial surveys 

 should be conducted at least once every 3 years, especially in valuable 

 resource areas or embayments undergoing rapid development. 



Sediment core analysis is the most accurate way of assessing past 

 local fluctuations in eelgrass abundance during this and previous 

 centuries. Furthermore, the physical and chemical characteristics of 

 core sections, along with the remains of plants and animals, can 

 document long term changes in nutrient levels, shellfish abundance, 

 sediment depositional rates, rates pollutant inputs, nutrient loading, 

 and macroalgal and periphyton abundance (Brush and Davis, 1984; Fry et 

 al., 1987, unpub. data). Sites for coring should be chosen carefully, 

 and best results are achieved in quiescent, depositional areas, away 

 from erosion and dredging influences (Davis, 1985). Together with 

 aerial surveys and other documentation, sediment core analysis is a 

 powerful tool for understanding the recent ecological history of coastal 

 waters. 



