Premium
Jelly biomass sinking speed reveals a fast carbon export mechanism
Author(s) -
Lebrato Mario,
Mendes Pedro de Jesus,
Steinberg Deborah K.,
Cartes Joan E.,
Jones Bethan M.,
Birsa Laura M.,
Benavides Roberto,
Oschlies Andreas
Publication year - 2013
Publication title -
limnology and oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 197
eISSN - 1939-5590
pISSN - 0024-3590
DOI - 10.4319/lo.2013.58.3.1113
Subject(s) - thermocline , oceanography , temperate climate , biogeochemical cycle , environmental science , biomass (ecology) , carbon fibers , seawater , marine snow , biological pump , gelatinous zooplankton , deep sea , carbon cycle , water column , zooplankton , ecology , environmental chemistry , chemistry , ecosystem , geology , biology , materials science , composite number , composite material
Sinking of gelatinous zooplankton biomass is an important component of the biological pump removing carbon from the upper ocean. The export efficiency, e.g., how much biomass reaches the ocean interior sequestering carbon, is poorly known because of the absence of reliable sinking speed data. We measured sinking rates of gelatinous particulate organic matter (jelly‐POM) from different species of scyphozoans, ctenophores, thaliaceans, and pteropods, both in the field and in the laboratory in vertical columns filled with seawater using high‐quality video. Using these data, we determined taxon‐specific jelly‐POM export efficiencies using equations that integrate biomass decay rate, seawater temperature, and sinking speed. Two depth scenarios in several environments were considered, with jelly‐POM sinking from 200 and 600 m in temperate, tropical, and polar regions. Jelly‐POM sank on average between 850 and 1500 m d −1 (salps: 800–1200 m d −1 ; ctenophores: 1200–1500 m d −1 ; scyphozoans: 1000–1100 m d −1 ; pyrosomes: 1300 m d −1 ). High latitudes represent a fast‐sinking and low‐remineralization corridor, regardless of species. In tropical and temperate regions, significant decomposition takes place above 1500 m unless jelly‐POM sinks below the permanent thermocline. Sinking jelly‐POM sequesters carbon to the deep ocean faster than anticipated, and should be incorporated into biogeochemical and modeling studies to provide more realistic quantification of export via the biological carbon pump worldwide.