Anyone else read this and think “Duh!”?

From: New Scientist published March 27, 2009, authored by Catherine Brahic

“Hungry shrimp eat climate change experiment”

“Earlier this month, the controversial Indian-German Lohafex expedition 
fertilised 300 square kilometres of the Southern Atlantic with six tonnes 
of dissolved iron. The iron triggered a bloom of phytoplankton, which 
doubled their biomass within two weeks by taking in carbon dioxide from 
the seawater. Dead bloom particles were then expected to sink to the ocean 
bed, dragging carbon along with them. Instead, the bloom attracted a swarm 
of hungry copepods. The tiny crustaceans graze on phytoplankton, which 
keeps the carbon in the food chain and prevents it from being stored in 
the ocean sink. Researchers from the Alfred Wegener Institute for Polar 
and Marine Research reported that the copepods were in turn eaten by 
larger crustaceans called amphipods, which serve as food for squid and fin 
whales.”

“The grazing effect had not been seen in previous fertilisation 
experiments. These had caused blooms of diatoms, a type of phytoplankton 
that is protected against grazers by a hard shell of silica. But the 
Lohafex experiment did not trigger a diatom bloom because there was little 
silicic acid available in the water for diatoms to build their shells 
from. Lohafex researchers say the results suggest that using iron 
fertilisation to increase the ocean carbon sink would rely on a complex 
chain of events, making it difficult to control. The Southern Ocean is 
thought to be the planet's largest ocean carbon sink. But most of the 
northern half of the region is low on silicic acid, ruling it out as an 
option for carbon fertilisation. The researchers tried to provoke a second 
bloom by fertilising the same patch of ocean three weeks later, with no 
success — most probably because the water was already saturated in 
iron. ‘It seems that if it is possible to fertilise enough ocean to make a 
difference to climate, we would need to turn vast ocean ecosystems into 
giant plankton farms,’ says Caldeira.”

David Hilmy
Chief Operations Officer, Director of Conservation,
KuTunza Environmental Education Program (KEEP)
Europe: 27 avenue de l'Opéra, 75001 Paris, France
USA: 2804 Shepherd Street, Mount Rainier, MD 20712
888.379.2879 ~ 202.379.2879 ~ 202.316.4902 (cell)

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