2016-07-28. How Irrigation in Asia Affects Rainfall in Africa.
By Sarah Stanley, EoS Earth and Space News, AGU.
2015-06-22. Amazon Rain Forest Nourished by African Dust.
By Terri Cook, EOS publication of AGU.
2009 October 15. Deep-Sea Microbes May Answer Long-Standing Question About Earth's Nitrogen Cycle. NSF Release 09-201.Excerpt:
...Although lightning, combustion, and other non-biological processes
can create reduced nitrogen, far more is generated by nitrogen-fixing
microorganisms such as bacteria, in particular, photosynthetic aquatic
cyanobacteria. These organisms produce the bulk of the nitrogen
available to living things in the ocean.
When researchers add up all known sources of fixed nitrogen--biological
and otherwise--in the global nitrogen cycle, and compare it to the sinks
(biological uptake for growth and energy), they come up short. More
nitrogen appears to be used than is being made. The "nitrogen budget,"
in effect, does not balance.
The question has been whether the nitrogen cycle is out of balance, or
whether the known inventories of sources and sinks are incomplete, says
Victoria Orphan, a geobiologist at Caltech.
Orphan, along with Caltech graduate student Anne Dekas and Caltech
postdoctoral researcher Rachel Poretsky, suggest the answer is, at least
in part, an incomplete catalogue of the sources of fixed nitrogen.
...The team studied ocean sediment samples in methane cold seeps 20
miles off northern California at a depth of 1,800 feet. The area, known
as the Eel River Basin, is in a region that supports high levels of
natural methane seepage at the sea-floor.
... tiny microbial conglomerations ... averaging 500 cells each, consist
of two types of anaerobic microorganisms living in a unique symbiotic
relationship fueled by methane. ... a bacterium ... reduces the chemical
sulfate into sulfide ...to generate energy. The second is a
methane-oxidizing archaeon ...Working together, these two symbionts are
responsible for consuming the majority of the naturally-released methane
in the deep sea.
Although these symbiotic associations themselves are not new--the
conglomerations were found about a decade ago--the scientists discovered
something unexpected: the methane-consuming archaea were actively
fixing nitrogen, and sharing it with their bacterial neighbors.
This is the first time nitrogen fixation has been documented in methane-oxidizing archaea, say the scientists....
2009 May 28. Serving Suggestion. By Karen Solomon, OnEarth (NRDC ISSUE: Summer 2009) Excerpt:
With Sasha and Malia growing arugula in the White House garden, and
with more and more farmers' markets on our streets, it seems shocking
that prefab Tater Tots and canned fruit cocktail should continue to rule
the lunchrooms of our public schools.
Until October 2005, the Berkeley Unified School District in California
was no exception. Its 9,000 students were served the usual highly
processed, highly subsidized heat-and-serve dreck that passed for the
noontime meal. That is, until Ann Cooper became director of nutrition
services, making a radical shift from chicken nuggets to real chicken,
fresh produce instead of ketchup packets, and whole-grain, real bean and
cheese nachos with not a can of cheese sauce in sight. Now Cooper, who
first made a name for herself on the celebrity-chef circuit, is taking
her mission and her menu to school cafeterias nationwide.
"High-fat, high-sugar, high-salt diets with very few fruits and
vegetables and no whole grains will lead to a generation of kids who,
for the first time, will die at a younger age than their parents," says
Cooper, citing Centers for Disease Control statistics that a third of
our nation's children are overweight or obese. Because minority students
are most affected by what's on the daily cafeteria tray, real lunch
reform is "the social justice issue of our time," Cooper says. "We can't
spend another dollar per day per child to feed them healthy food?" she
yells in exasperation. "We can either pay for lifelong wellness now, or
pay later for a tsunami of diabetes. And these kids can't learn if
they're not well nourished."...
2008 July 18. Saharan dust storms sustain life in Atlantic Ocean. Eureka Alert. Excerpt:
Research at the University of Liverpool has found how Saharan dust
storms help sustain life over extensive regions of the North Atlantic
Working aboard research vessels in the Atlantic, scientists mapped the
distribution of nutrients including phosphorous and nitrogen and
investigated how organisms such as phytoplankton are sustained in areas
with low nutrient levels.
They found that plants are able to grow in these regions because they
are able to take advantage of iron minerals in Saharan dust storms. This
allows them to use organic or 'recycled' material from dead or decaying
plants when nutrients such as phosphorous – an essential component of
DNA – in the ocean are low...
"These findings are important because plant life cycles are essential in
maintaining the balance of gases in our atmosphere. In looking at how
plants survive in this area, we have shown how the Atlantic is able to
draw down carbon dioxide from the atmosphere through the growth of
2005 April 21. NASA RELEASE: 05-100. NASA Study Finds Snow Melt Causes Large Ocean Plant Blooms. A
NASA funded study has found a decline in winter and spring snow cover
over Southwest Asia and the Himalayan mountain range is creating
conditions for more widespread blooms of ocean plants in the Arabian
Sea. The decrease in snow cover has led to greater differences in both
temperature and pressure systems between the Indian subcontinent and the
Arabian Sea. The pressure differences generate monsoon winds that mix
the ocean water in the Western Arabian Sea. This mixing leads to better
growing conditions for tiny, free-floating ocean plants called
phytoplankton. ...When winter and spring snow cover is low over Eurasia,
the amount of solar energy reflected back into the atmosphere is less. A
decline in the amount of snow cover means less of the sun's energy goes
towards melting of snow and evaporation of wet soil. As a result the
land mass heats up more in summer creating a larger temperature
difference between the water of the Arabian Sea and the Indian
subcontinent landmass. The temperature difference is responsible for a
disparity in pressure over land and sea, creating a low pressure system
over the Indian subcontinent and a high pressure system over the Arabian
Sea. This difference in pressure causes winds to blow from the
Southwest Arabian Sea bringing annual rainfall to the subcontinent from
June to September. In the Western Arabian Sea, these winds also cause
upwelling of cooler nutrient-rich water, creating ideal conditions for
phytoplankton to bloom every year during summer. ... while large blooms
of phytoplankton can enhance fisheries, exceptionally large blooms could
be detrimental to the ecosystem. Increases in phytoplankton amounts can
lead to oxygen depletion in the water column and eventually to a
decline in fish populations. More info.
Articles from 2005–present
2: Energy Through a System
5: Carbon in the Biosphere
5: Soil, the Living Skin of the Earth
7: One Global Ocean