Nitrite, versus density

Fig. 2 Vertical distribution of temperature (T), salinity (S), dissolved oxygen (02), hydrogen sulfide (H2S), dissolved manganese (Mn diss), nitrate (NO3), nitrite (NO2), ammonia (NH4), phosphate (P04), silicate (Si), pH (pH), total alkalinity (Aik), methane (CH4), organic phosphorus (Porg), organic nitrogen (Norg), and urea (Urea), at a station near Gelendzhik (St. 2618, September, 2006). Concentrations of chemical parameters are in aM. Distributions are plotted versus depth (m) at the top and versus density (agy kg nr3) at the bottom...

When the data are plotted versus density, all of the profiles from different locations fall together in a narrow range. The data for dissolved oxygen, sulfide, iron, and manganese are shown in Figure 5, and the data for dissolved nitrate, nitrite, ammonia, and phosphate are shown in Figure 6. Features in the water column occur at different depths at different locations, but they always occur close to the same density surface. The only exceptions appear to occur in the region close to the Bosporus, where the Black Sea inflow interleaves with ambient water. 

Figure 6. Pump cast profiles of nitrate, nitrite, ammonia, and phosphate versus density (

The cell concentration was determined by optical density (OD) measurement at 600 nm and compared with an OD versus dry weight calibration curve. Nitrate and nitrite concentrations were measured using a segmented flow analyzer (Skalar analytic ). Nitrite detection was based on the colorimetric reaction with N-(l-naphthyl)-ethylenediamine nitrate was detected as nitrite by the same method after reduction by hydrazine. DOC was also measured using the segmented flow analyzer. Carbon compounds were detected as... 

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