/* DATA DESCRIPTION:
Citation:	Wasmund, Norbert (2015): Depth integrated nitrogen fixation from the northern Benguela upwelling system during Maria S. Merain cruise MSM18/4 [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.843444
Abstract:	Nitrogen fixation data from the cruise number MSM18/4 with research vessel "Maria S. Merian" from 24.07.-20.08.2011 (from Libreville to Walvis Bay) in front of Angola and northern Namibia. Samples taken by CTD- rosette sampler from different depths and incubated in glass bottles (535 ml) at light intensities that resemble the in situ light intensities of the sampling depth after Delta 15 N2 gas was injected to the sample. After the incubation time of 6 hours, the complete bottle content was filtered onto a pre-combusted Whatman GF/F filter. Filters were frozen, transported to the institute on dry ice and measured in a mass spectrometer for Delta15N. The principle of the method was described by Montoya et al. (1996) and calculation was done according to their spread sheet. From the data of the single depths, the nitrogen fixation per square meter within the upper 40 m of the water column was calculated. The methods are described in detail in a paper submitted by Wasmund et al. in 2014 to be printed in 2015. Some results are surprisingly below zero. This occurs if the Delta15N of the blank is higher than the measurement after incubation. It indicates that no nitrogen fixation occurred. Due to natural variability, the variability of the nitrogen fixation data is high. In an overall estimate, also over several cruises, negative and positive values compensate more or less, suggesting that nitrogen fixation is insignificant in the waters in front of northern Namibia and southern Angola.
Related to:	Wasmund, Norbert; Struck, Ulrich; Hansen, A; Grüttmüller, A; Flohr, Anita; Nausch, Günther; Voss, Maren (2015): Missing nitrogen fixation in the Benguela region. 106, 30-41, https://doi.org/10.1016/j.dsr.2015.10.007
Project(s):	Geochemistry and ecology of the Namibian upwelling system (GENUS) (URI: https://genus.cen.uni-hamburg.de/html/index.html)
Funding:	Bundesministerium für Bildung und Forschung, Bonn (BMBF) (URI: https://www.bmbf.de), grant/award no. 03F0650: Geochemistry and ecology of the Namibian upwelling system
Coverage:	MEDIAN LATITUDE: -13.242906 * MEDIAN LONGITUDE: 11.102921 * SOUTH-BOUND LATITUDE: -17.249330 * WEST-BOUND LONGITUDE: 8.000000 * NORTH-BOUND LATITUDE: -10.497000 * EAST-BOUND LONGITUDE: 13.580830
	DATE/TIME START: 2011-07-28T04:12:00 * DATE/TIME END: 2011-08-15T04:04:00
	MINIMUM DEPTH, water: 20 m * MAXIMUM DEPTH, water: 20 m
Event(s):	MSM18/4_790 (AG11050) * LATITUDE: -10.999660 * LONGITUDE: 8.000000 * DATE/TIME: 2011-07-28T04:12:00 * ELEVATION: -4884.7 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, drift net, Plankton net
	MSM18/4_795 (AG14090) * LATITUDE: -13.999330 * LONGITUDE: 10.122660 * DATE/TIME: 2011-07-29T08:44:00 * ELEVATION: -3889.8 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, Plankton net, Satlantic, Secchi disc
	MSM18/4_802 (IP_Na5) * LATITUDE: -15.094000 * LONGITUDE: 12.106330 * DATE/TIME: 2011-07-30T09:13:00 * ELEVATION: -67.7 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, Dredge, multi net, Plankton net, Satlantic, Secchi disc Tucker trawl, van Veen grab
	MSM18/4_811 (IP_Lo4) * LATITUDE: -12.333000 * LONGITUDE: 13.432160 * DATE/TIME: 2011-07-31T19:49:00 * ELEVATION: -99.4 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, Dredge, drift net, multinet, Plankton net, Tucker trawl, van Veen grab
	MSM18/4_813 (IP_Su5) * LATITUDE: -10.497000 * LONGITUDE: 13.580830 * DATE/TIME: 2011-08-01T11:20:00 * ELEVATION: -25.0 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, Dredge, drift net, multinet, Plankton net, Satlantic,Secchi disc Tucker trawl, van Veen grab
	MSM18/4_816 (IP_Su2) * LATITUDE: -10.500330 * LONGITUDE: 12.999160 * DATE/TIME: 2011-08-01T20:48:00 * ELEVATION: -612.1 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, drift net, multi net, Plankton net
	MSM18/4_827 (AG10502) * LATITUDE: -10.500000 * LONGITUDE: 11.846830 * DATE/TIME: 2011-08-04T05:12:00 * ELEVATION: -1887.8 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, drift net, multi net, Plankton net, Satlantic, Secchi disc
	MSM18/4_831 (AG12502) * LATITUDE: -12.499160 * LONGITUDE: 10.865330 * DATE/TIME: 2011-08-04T21:28:00 * ELEVATION: -3578.2 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, drift net, multi net
	MSM18/4_837 (AG15080) * LATITUDE: -14.999330 * LONGITUDE: 9.623000 * DATE/TIME: 2011-08-06T04:13:00 * ELEVATION: -4067.6 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, drift net, multi net, Plankton net
	MSM18/4_842 (AG17002) * LATITUDE: -17.000830 * LONGITUDE: 8.555830 * DATE/TIME: 2011-08-07T14:45:00 * ELEVATION: -4752.2 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, drift net, multi net, Plankton net
	MSM18/4_848 (IP_Ku1) * LATITUDE: -17.249330 * LONGITUDE: 11.000000 * DATE/TIME: 2011-08-15T04:04:00 * ELEVATION: -2107.2 m * CAMPAIGN: MSM18/4 * BASIS: Maria S. Merian (URI: https://en.wikipedia.org/wiki/RV_Maria_S._Merian) * METHOD/DEVICE: CTD/Rosette (CTD-RO) * COMMENT: CTD, multi net, Plankton net
Parameter(s):	Event label (Event)
	Optional event label (Event 2)
	Sample ID (Sample ID) * PI: Wasmund, Norbert (https://orcid.org/0000-0002-7979-7176, norbert.wasmund@io-warnemuende.de)
	Latitude of event (Latitude)
	Longitude of event (Longitude)
	Date/Time of event (Date/Time)
	DEPTH, water [m] (Depth water) * GEOCODE
	Depth, top/min [m] (Depth top) * PI: Wasmund, Norbert (https://orcid.org/0000-0002-7979-7176, norbert.wasmund@io-warnemuende.de)
	Depth, bottom/max [m] (Depth bot) * PI: Wasmund, Norbert (https://orcid.org/0000-0002-7979-7176, norbert.wasmund@io-warnemuende.de)
	Nitrogen fixation rate, integrated per hour [µmol/m**2/h] (N fix int) * PI: Wasmund, Norbert (https://orcid.org/0000-0002-7979-7176, norbert.wasmund@io-warnemuende.de) * METHOD/DEVICE: Calculated according to Montoya et al. (1996) (URI: https://doi.org/10.1128/aem.62.3.986-993.1996)
License:	Creative Commons Attribution 3.0 Unported (CC-BY-3.0) (URI: https://creativecommons.org/licenses/by/3.0/)
Size:	44 data points
*/
Event	Event 2	Sample ID	Latitude	Longitude	Date/Time	Depth water [m]	Depth top [m]	Depth bot [m]	N fix int [µmol/m**2/h]
MSM18/4_790	AG11050	790	-10.9997	8.0000	2011-07-28T04:12	20	0	40	2.075
MSM18/4_795	AG14090	795	-13.9993	10.1227	2011-07-29T08:44	20	0	40	-1.823
MSM18/4_802	IP_Na5	802	-15.0940	12.1063	2011-07-30T09:13	20	0	40	-4.080
MSM18/4_811	IP_Lo4	811	-12.3330	13.4322	2011-07-31T19:49	20	0	40	-0.823
MSM18/4_813	IP_Su5	813	-10.4970	13.5808	2011-08-01T11:20	20	0	40	-0.534
MSM18/4_816	IP_Su2	816	-10.5003	12.9992	2011-08-01T20:48	20	0	40	0.680
MSM18/4_827	AG10502	827	-10.5000	11.8468	2011-08-04T05:12	20	0	40	-0.683
MSM18/4_831	AG12502	831	-12.4992	10.8653	2011-08-04T21:28	20	0	40	1.140
MSM18/4_837	AG15080	837	-14.9993	9.6230	2011-08-06T04:13	20	0	40	1.473
MSM18/4_842	AG17002	842	-17.0008	8.5558	2011-08-07T14:45	20	0	40	0.060
MSM18/4_848	IP_Ku1	848	-17.2493	11.0000	2011-08-15T04:04	20	0	40	0.614