An Empire Lacking Food
Once viewed as a barren expanse, the deep seafloor is a biologically elaborate ecosystem whose fate is tied to life above, near the sea surface
An Uncertain Future
I write about our growing insight into the deep sea as Earth is entering another period of momentous fluctuation. As the emission of greenhouse gases changes our planet’s climate, evidence is growing that we have already altered the production and movement of carbon in the oceans. Recent work demonstrates that some areas in the oceans have seen 50-percent reductions in phytoplankton production, whereas others have experienced 50-percent increases. Daniel Boyce of Dalhousie University and his colleagues recently reported that phytoplankton production globally has declined over the last century. This redistribution and reduction of carbon at the ocean surface could alter the deep sea in profound ways in the near decades. Yet, changes in carbon cycling are just one of many daunting threats facing the oceans. A combination of overfishing, pollution, mining, warming and acidification may prove a dangerous cocktail.
Deep-sea organisms exist at environmental extremes of temperature, pressure and, of course, food availability. Across levels of biological organization, from individuals to the ecosystem, extraordinary ecological and evolutionary transformations have taken place in lockstep with those limits. As human activity further alters the deep sea, will its species adapt or perish?
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