The major modal values for RPD depths were shared between 

 the 4 and 5 cm class interval (Figure 3-59). In September 1984, 

 the RPD distribution had a modal value of 3 cm. The mapped RPD 

 values (Figure 3-60) showed relatively deep values at all stations 

 except for 300S/100E and 300S/300E, where the apparent RPD was less 

 than 3 cm deep. 



All MQR stations exhibited Stage I seres except for 

 stations 500N/500E and 300S/300E (Figure 3-61) . Past experience 

 with the recolonization of other DAMOS mounds has shown that Stage 

 III taxa normally appear on disposed materials within one year, 

 initially on the thin flank deposits. The MQR mound is anomalous 

 in this respect; sediment chemical contaminants are a potential 

 cause for the slow recolonization rate of this mound. 



Most of the OSI values fell within the modal value of +7 

 (Figure 3-59) , indicative of relatively deep RPD values and 

 low-order successional infauna. In September 1984, the major mode 

 was shared between the +5 and +6 classes. The mapped OSI values 

 showed a remarkably uniform distribution over the mound, suggesting 

 that small-scale heterogeneity was not present (Figure 3-62) . The 

 whole mound appeared to be held in a late Stage I condition. 



Post Storm Survey 



On 29 October 1985, one month after Hurricane Gloria, 

 the MQR disposal mound was surveyed to assess the impacts of the 

 storm. The post-storm benthic process map of the MQR mound (Figure 

 3-63) indicated much less evidence of physical disturbance than the 

 images from the other CLIS mounds (including FVP) . A typical image 

 from the MQR post-storm survey revealed (Figure 3-64) a smooth 

 bottom colonized by a Stage I assemblage (sedimentary methane is 

 also evident in this image) . Methane was observed at two stations, 

 2 00N and CTR, indicating high sediment BOD and COD. Methane had 

 not been observed in the August survey. 



Boundary roughness values did not change at MQR between 

 August and October, supporting the interpretation that bottom 

 disturbance due to the hurricane was minimal at this mound. The 

 post-storm distribution of RPD depths at MQR (Figure 3-65) 

 indicated that, as observed at the other CLIS disposal mounds, RPD 

 values had decreased at MQR since the August survey (compare with 

 Figure 3-60; Mann-Whitney U-test, p < 0.001). There was no obvious 

 spatial pattern in the distribution of RPD values indicating a 

 mound-wide disturbance. The presence of methane suggested that 

 organic loading may have been a contributing stress factor. 

 Despite the lack of direct evidence, hurricane-induced disturbance 

 could not be ruled out completely. 



The distribution of infaunal successional stages at the 

 MQR mound (Figure 3-66) showed only two stations with Stage III 



17 



