o 



I- 

 < 



u 



UJ 



cr 

 a. 



T 1 1 r 



Figure 23-2. Monthly Rainfall Since 1960 at a Selected Rain 

 Gauge in the Kaneohe Bay Watershed. 



of hard substratum for settlement; particulate material in the water column 

 lowers light and interferes with feeding mechanisms. 



Nutrient loading from sewage discharge has increased about sixfold since 

 1963 (Figure 23-3). This increase is consistent with the previously cited rate of 

 human population increase in the Kaneohe watershed. Virtually the entire 

 nutrient load delivered to Kaneohe Bay is stripped from the water by biological 

 uptake. There have been several obvious responses to the increased nutrient 

 loading. Benthic algae are locally abundant on the reef flats and compete 

 successfully vWth the corals for space on the reef slopes (2). The zone of 

 present algal dominance on the reef slopes corresponds with the zone left 

 undamaged by the 1965 freshwater kill. Phytoplankton standing crop and 

 productivity are elevated above pre-loading levels; included in this high 

 standing crop are frequent plankton "blooms" (4, plus our ovw data). Various 



350 



