Cruise No. EP12-1

Access URI: https://www.incois.gov.in/IIOE-2/EP12-1Info.jsp

Alternate Title: Dust Stimulated Nitrogen Fixation in the Arabian Sea - an assessment of HNLC region hypothesis (DUSTNIF)

Brief Description (Abstract):

The oceans act as a major sink for anthropogenic CO2 through primary production. Though the Arabian Sea (area ~6.2 * 10^6 km2) covers only about 1% of the global ocean surface but contributes up to 5% of the global marine primary production2, partly due to high influx of `new` nitrogen via diazotrophic N2 fixation. Iron, whose main source in the ocean is atmospheric transport of dust, is an essential nutrient for sustaining N2 fixation. Despite being in the vicinity of the Thar desert on the east and the Arabia desert on the west, the Arabian Sea has been recently hypothesized to be an HNLC (high nutrient low chlorophyll) region (Naqvi et al., Biogeosciences, 2010). One of the most spectacular biological phenomena is the occurrence of annual spring Trichodesmium blooms in the Arabian Sea. There is a north-south gradient in dust deposition. We hypothesize (i) that this gradient plays a major role in Trichodesmium distribution, and (ii) the HNLC region could be limited just to the south Arabian Sea. In order to test our hypotheses, this project aims a comprehensive study of N2 fixation rates, chemical characterization of the dust and sea water, primary production and community structure analysis along the three transacts in the Arabian Sea during April 2017 onboard FORV Sagar Sampada and on a couple of cruises in coming years.

Status: Completed

Purpose: To investigate dust-induced primary productivity and nitrogen fixation in the Arabian Sea

Credit(s): Dr. Arvind Singh

Edition: 01

Edition Date: 2019-08-23

Presentation Format: TableDigital

Distribution Format: Unknown

Distribution Format Version: Unknown

Supplemental Information:

IIOE-2 endorsed project. The project aligns with IIOE-2 Science Theme 6 (Unique geological, physical, biogeochemical, and ecological features of the Indian Ocean).

Keyword(s): Earth Science-Oceans-Ocean Chemistry-Nitrate, Earth Science, Earth Science-Atmosphere, Earth Science-Oceans-Ocean Chemistry-Nutrients, Earth Science-Oceans-Ocean Chemistry-Nitrogen, Earth Science-Oceans-Ocean Chemistry-Ph, Earth Science-Oceans-Ocean Chemistry-Suspended Solids, Earth Science-Oceans, Earth Science-Oceans-Ocean Chemistry-Chlorophyll, Earth Science-Oceans-Ocean Chemistry-Inorganic Carbon, Earth Science-Oceans-Ocean Chemistry-Marine Geochemistry,

Place/Location(s): Central Arabian Sea,

Project: IIOE-2,

Topic Category(s): GeoScientific Information,

Date(s): 2018-02-09 (Publication), 2018-02-09 (Creation),

Resource Contact(s):
1. Name : Dr. Arvind Singh
    Position : Scientist
    Role : PrincipalInvestigator
    Phone : +91 79 2631 4153
    E-Mail : arvinds [ at ] prl.res.in
    Organization Name : Physical Research Laboratory (PRL)
    Address : Geosciences Division, Physical Research Laboratory, Navrangpura
    City : Ahmedabad
    State : Gujarat
    Postal Code : 380 009
    Country : IND

Distributor Contact(s):
1. Name : Dr S. Rajan
    Position : JPO INDIA IIOE-2 Coordinator
    Role : Distributor
    Phone : +91-40-23886142
    E-Mail : iioe-2 [ at ] incois.gov.in
    Organization Name : Indian National Centre for Ocean Information Services (INCOIS)
    Address : Ocean Valley, Pragathi Nagar (BO), Nizampet (SO)
    City : Hyderabad
    State : Telangana
    Postal Code : 500090
    Country : IND

Metadata Contact(s):
1. Name : Dr. Arvind Singh
    Position : Scientist
    Role : PointOfContact
    Phone : +91 79 2631 4153
    E-Mail : arvinds [ at ] prl.res.in
    Organization Name : Physical Research Laboratory (PRL)
    Address : Geosciences Division, Physical Research Laboratory, Navrangpura
    City : Ahmedabad
    State : Gujarat
    Postal Code : 380 009
    Country : IND

Extent:
Start Date : 2017-04-15
End Date   : 2017-05-03