APPENDIX D 



STUDY DESIGN RESTRICTIONS 



The primary purpose of this study was to collect data on the benthic 

 macroinf^una and the surface sediments to evaluate the long-term effects of 

 beach nourishment and associated dredging activities. Inherent in any 

 environmental study are limitations on the quantity and types of data that 

 can be collected. A good study plan requires that the data collected 

 enable the investigators to differentiate between manmade and natural per- 

 turbations. If no effects can be detected, then by definition there has 

 been no environmental harm. This emphasizes the need to conduct scientifi-- 

 cally valid studies utilizing beat applicable methodologies. Potential 

 limiting factors encountered in this study are discussed below. 



Sampling Design Adequacy . 



The accuracy of the data collected for the present study and the 

 validity of the interpretations and comparisons made to the base-line study 

 (Saloman, 1976) are dependent on the adequacy of the sampling design. Some 

 of the key factors in establishing sampling and analysis adequacy are: 



(a) Reliability and accuracy of sampling device (consistent sub- 

 strate penetration, no loss of sample during retrieval, etc.). 

 Characteristics for a good sampling device are described by Menzies 

 and Rowe (1968) and Holme and Mclntyre (1971) . 



(b) Adequate sieve size to retain a majority of the macrofauna 

 (Reish, 1959). 



(c) Good and consistent procedures to ensure proper preservation 

 of fauna . 



(d) Adequate niomber of stations to determine spatial varability 

 of fauna. 



(e) Sufficient replication to adequately describe both the within- 

 station faunal variation, and the majority of the species inhabiting 

 the site. 



(f) Sufficient temporal frequency of sampling :o address seasonal 

 variations in fauna. 



(g) The use of identical or comparable methodologies for both 

 prenourishment and postnouris:hment studies. 



(h) Sound taxonomic procedures and use of expert confirmations to 

 ensure accurate identification of organisms. 



(i) Consistent data analysis procedures. 



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