Seagrasses and Carbon: study shows they store carbon as well as forests

A press release issued today by the National Science Foundation highlights a recent study that shows that seagrasses are able to store as much carbon as forests.  Florida International University and the National Science Foundation's Florida Coastal Everglades Long-Term Ecological Research site worked together with scientists from Spain, Australia, United Kingdom, Denmark, and Greece to determine that, although seagrass meadows occupy less than 0.2 percent of the world's oceans, they are responsible for more than 10 percent of all the carbon buried annually in the sea.

"Seagrasses are a vital part of the solution to climate change and, per unit area, seagrass meadows can store up to twice as much carbon as the world's temperate and tropical forests.  The [study] results demonstrate that coastal seagrass beds store up to 83,000 metric tons of carbon per square kilometer, mostly in the soils beneath them. As a comparison, a typical terrestrial forest stores about 30,000 metric tons per square kilometer, most of which is in the form of wood," the press release stated. 

"Seagrasses have the unique ability to continue to store carbon in their roots and soil in coastal seas," said James Fourqurean, Florida International University scientists and lead author of the study. "We found places where seagrass beds have been storing carbon for thousands of years."       

And like forests that are subject to deforestation for land development and lumber, seagrasses are among the world's most threatened ecosystems.  Some 29 percent of all historic seagrass meadows have been destroyed, mainly due to dredging and degradation of water quality.  At least 1.5 percent of the Earth's seagrass meadows are lost every year.   

Seagrasses can, when properly managed, regenerate themselves, perhaps even better than denuded forests. According to Karen McGlathery, one of the study's co-authors and a scientist at the University of Virginia, "One remarkable thing about seagrass meadows is that, if restored, they can effectively and rapidly sequester carbon and reestablish lost carbon sinks."       

Besides the ability to sequester carbon, seagrasses play an important role in filtering sediment from the ocean, protecting the shoreline from flood and storm damage, and providing shelter for a variety of marine life and their offspring.  The study's conclusions emphasize the need for conserving and restoring seagrass meadows as they reduce greenhouse gas emissions and increase carbon stores while delivering important ecological benefits to coastal communities as well.  

Source: NSF.gov
                 

Ocean Trash & Climate Change: California takes some small steps in research and adaptation

A couple of interesting items coming out of my home state of California:

You may have heard of the Great Pacific Ocean Garbage Patch, this floating mat of various plastic and trash items that has accumulated due to a convergence of several ocean currents. The "patch" is no small area, estimated to be almost twice the size of the state of Texas and posing an obvious health hazard to sea animals, like sea birds (who mistakenly feed on the debris), or land animals (as fragments of the patch float ashore).

Researchers and students from the Scripps Institution of Oceanography in San Diego, CA are planning a 20-day expedition to better map out this growing reminder of our non-biodegradable product dependence. They will investigate to determine it's size, depth, and make-up. And they will examine its contents in detail to determine whether it is harboring additional pollutants or any invasive species.

What's to be done about the garbage patch in the future remains unclear. Formed by oceanic forces out of our control and residing in open international waters, addressing its removal has been an international and diplomatic challenge. Certainly we know what to do to not add anymore waste to it, but how do we deal with the current situation? Hopefully, an international solution will be reached but it will require considerable technological and logistical resources.

California has often taken stronger environmental positions than those emanating from the federal government, but that is because California lawmakers recognize that the state, both, has a lot to lose if nothing substantial is done, and that the state has been a major contributor over the years to environmental problems ranging from CO2 emissions to overfishing.

In Yosemite National Park, research has been taking place to compare the growth of large-diameter trees. Comparing records dating back to the early 30's, it has been determined that there has been a marked reduction in the density of these trees by as much as 24%.

"Climate change is a likely contributor to these events and should be taken into consideration," said Jan van Wagtendonk, a U.S. Geological Survey scientist. "Warmer conditions increase the length of the summer dry season and decrease the snowpack that provides much of the water for the growing season. A longer summer dry season can also reduce tree growth and vigor, and can reduce trees' ability to resist insects and pathogens."

In addition to the reduced growth, the current condition of the trees exposes them to greater wildfire danger, as there has been a marked shift in some areas from ponderosa pines, a more fire-retardant species, to less fire-retardant white fir and incense cedar.

While California attempts to push some of the boundaries of environmental policy, it apparently recognizes the bureaucratic logjam that impedes new direction in national and international energy and environmental strategies. The California Natural Resource Agency has issued a preliminary report for public review on the subject of climate adaptation - a strategy wherein it is recognized that there will be inevitable climate-related changes and proposes changes in policies and regulations to deal with them. This means preparing for the worst: heat-waves, rising sea levels, flooding, wildlife die-offs, and more.

It is somewhat reassuring to know that a government agency truly recognizes the implications of climate change. But it is unfortunate that this realization comes at a time when, apparently, prevention is not an option regarding some of its impact. This is not to say that we should throw up our hands in defeat. On the contrary, it is reason for us to double our efforts so as to minimize these effects and perhaps even reverse them in the future.