geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Chemical determination of particulate nitrogen in san francisco bay california usa nitrogen chlorophyll a ratios in plankton


, : Chemical determination of particulate nitrogen in san francisco bay california usa nitrogen chlorophyll a ratios in plankton. Estuarine Coastal & Shelf Science 19(2): 193-204

Particulate nitrogen (PN) and chlorophyll a (Chla) were measured in the northern reach of San Francisco Bay throughout 1980. The PN values were calculated as the differences between unfiltered and filtered (0.4 .mu.m) samples analyzed using the UV-catalyzed peroxide digestion method. The Chla values were measured spectrophotometrically, with corrections made for phaeopigments. The plot of all PN/Chla data was non-linear and the concentration of suspended particulate matter (SPM) was the best selector for linear subsets of the data. The best-fit slopes of PN/Chla plots, as determined by linear regression (model 2), were interpreted to be the N:Chla ratios of phytoplankton. The Y-intercepts of the regression lines were considered to represent easily-oxidizable detrital nitrogen (EDN). In clear water (< 10 mg l-1 SPM), the N:Chla ratio was 1.07 .mu.g-at N/.mu.g Chla. It decreased to 0.60 in the 10-18 mg l-1 range and averaged 0.31 in the remaining 4 ranges (19-35, 35-65, 65-155 and 155-470 mg l-1). The EDN values were < 1 .mu.g-at N l-1 in the clear water and increased monotonically to almost 12 .mu.g-at N l-1 in the highest SPM range. The N:Chla ratios for the 4 highest SPM ranges agree well with data for phytoplankton in light-limited cultures. In these ranges, phytoplankton-N averaged only 20% of the PN, while EDN averaged 39% and refractory-N 41%.

US$29.90


Other references

Kühn, D.; Juhr, N.; Rommel, M.; Boch, J., 1974: Experimental Toxoplasma infections in the cat. 3. Developmental stages in the cat intestine following oral Toxoplasma oocyst infection. Berliner und Munchener Tierarztliche Wochenschrift 87(3): 41-46

Becker, James M., 2002: Response of wintering bald eagles to industrial construction in southeastern Washington. Wintering bald eagles (Haliaeetus leucocephalus) use night roost trees located along the Columbia River shoreline at the Hanford Site in southeastern Washington state for daytime perching. The Hanford Bald Eagle Site Management Plan requires evalu...

Harris, J., 2002: Biphasic defibrillation. Emergency Nurse 10(7): 33-37

Schneider, U.; Mueller-Vahl, K.R.; Stuhrmann, M.; Gadzicki, D.; Heller, D.; Seifert, J.; Emrich, H.M., 2000: Die Bedeutung des endogenen Cannabinoidsystems bei verschiedenen neuropsychiatrischen Erkrankungen. The endogenous cannabinoid system was first described in 1988. There are two specific receptors, the CB2-receptor, located in the lymphatic system (spleen, lymphocytes), and the CB1-receptor occurring predominantly in the central nervous system. T...

Heckman, C.W., 1982: Atmospheric aerosol. On the basis of Pauling's first rule for ionic bonding, the coordination number of cations with oxygen anions can be determined by comparison of their relative ionic size ratio. In contrast to simple oxides, various site occupancies by multic...

Frost John E., 1958: Geology of the Larap iron ores, Camarines Norte. Philippine Geologist 12(1): 115-116

Yao, M.; Henny, C.; Maresca, J.A., 2016: Freshwater bacteria release methane as a byproduct of phosphorus acquisition. NlmCategory="UNASSIGNED">Freshwater lakes emit large amounts of methane, some of which is produced in oxic surface waters. Two potential pathways for aerobic methane production exist: methanogenesis in oxygenated water, which has been...

Dobrovol'skaya Z.A.; Gubkin V.A.; Motuznyi V.A., 1983: Amygdalo hypothalamic effects in the regulation of motor and evacuatory functions of the digestive tract. The effects of the amygdaloid nuclei on hypothalamic structures, which regulate the motor and evacuatory activity of the gastrointestinal tract, were studied in a chronic experiment with dogs. The regulation of the motor and evacuatory activity of...

Simek, V.S.ros, F., 1975: Continuous cultivation of microorganisms in installations with partical medium circulation. iI. Kvasny prumysl: 21 (10) 226-229

Holliday, C.M.; Gardner, N.M.; Paesani, S.M.; Douthitt, M.; Ratliff, J.L., 2010: Microanatomy of the mandibular symphysis in lizards: patterns in fiber orientation and Meckel's cartilage and their significance in cranial evolution. Although the mandibular symphysis is a functionally and evolutionarily important feature of the vertebrate skull, little is known about the soft-tissue morphology of the joint in squamate reptiles. Lizards evolved a diversity of skull shapes and f...