Smithsonian at the Poles: Contributions to International Polar

INTERANNUAL VARIABILITY IN LIGHT ATTENUATION 277
FIGURE 5. Chlorophyll a (chl) values measured in 2004, 2005, and 2006. Samples were collected at (top) 2 m and (bottom) 4 m water depth.
TABLE 1. Measurements of ammonium, phosphate, silicate, and nitrate � nitrite at 30 sites measured annually in July and August 2004,
2005, and 2006. Samples were collected at 2 and 4 m water column depths. Values are x � SE.
Nitrate � Nitrate �
Phosphate Phosphate Silicate Silicate Nitrite Nitrite
YEAR Ammonium Ammonium (PO4 3� ) (PO4 3� ) (SiO4) (SiO4) (NO 2� � (NO 2� �
�M (NH4 � ) 2 m (NH4 � ) 4 m 2 m 4 m 2 m 4 m NO 3� ) 2 m NO 3� ) 4 m
2004 0.12 � 0.06 0.17 � 0.07 0.24 � 0.03 0.19 � 0.05 1.76 � 0.18 1.84 � 0.26 0.14 � 0.10 0.15 � 0.01
2005 0.40 � 0.04 0.65 � 0.05 0.29 � 0.01 0.35 � 0.01 5.64 � 0.19 5.19 � 0.16 0.21 � 0.04 0.29 � 0.08
2006 0.25 � 0.05 0.12 � 0.02 0.17 � 0.01 0.20 � 0.01 7.05 � 0.14 6.89 � 0.16 0.07 � 0.01 0.10 � 0.02
Chl
(�g/L)
0.00 - 0.25
0.26 - 0.50
0.51 - 0.75
0.76 - 1.00
1.01 - 1.25
1.26 - 1.50
1.51 - 1.75
1.76 - 2.00
2.01 - 2.25
2.26 - 2.50
2.51 - 2.75