Category: Earth & Nature

Sinking down to the summit

By Marci Wills, May 2, 2010

Scientists like to categorize life on Earth into “biomes”. This is just a fancy name for regions characterized by similar biological and physical characteristics. For example, rain forests, temperate forests, savannas and deserts are some of the most well known and explored biomes. Little is known however, about many biomes of the oceans. Just last week, scientists from NOAA and Texas A&M- Corpus Christi revealed data suggesting that oceanic seamounts comprise one of the most widespread and diverse biomes on Earth.

Seamounts are underwater mountains which rise from the ocean floor but do not break the water’s surface. Most often they are extinct volcanoes, as in the emperor seamounts which are an extension of the Hawaiian Islands. Previous perception has been that seamounts were isolated and remote, but this idea is gradually changing. In their paper published last week in Oceanography, Peter Etnoyer, John Wood and Thomas Shirley claim that seamounts cover a substantial portion of the Earth, an area collectively larger than Australia.

Global distribution of 11,880 seamounts rising over 1000m above the seafloor

Their study used “satellite altimetry”, where specially-equipped satellites use radar beams to measure the elevation of the earth and sea level to within a few cm of accuracy. The use of satellite altimetry on the deep ocean floor is less precise, so the researchers looked for the most prominent seamounts rising at least 1000 meters. They counted about 11,880 of these worldwide, covering a cumulative area of 9,938,000 square kilometers, and that is their conservative estimate. That would make seamounts one of the most prevalent biomes in the world, ranking about even with the global extent of tropical humid forests, temperate broadleaf forests and wetlands.

Although organisms living on many seamounts never see sunlight, are surrounded by cold temperatures and high salinity water, and must rely on material falling from the surface waters for food, these elevated regions are undersea islands of biodiversity, sustaining much more life than surrounding seafloor. Only 200 seamounts have been thoroughly explored, but new species have been observed on nearly every submarine dive. In the Gulf of Alaska, two dozen new species of corals and sponges have been collected from seamounts since 2002.

This study demonstrates that rather than isolated features, seamounts often occur in dense clusters which vary significantly in size and number. The densest aggregation of seamounts is in the center of the Pacific Ocean where they are concentrated in a region exceeding the area of China. According to Project leader Peter Etnoyer, “Unlike beaches or coral reefs, most people will never see a seamount, but this study shows that they are clearly one of the predominant ecosystems on the planet”.

Sources:

Entnoyer, P.J., Wood, J., and Shirley, T.C., 2010, How large is the seamount biome?: Oceanography, v. 23, p. 206-209.

http://www.eurekalert.org/pub_releases/2010-04/nh-sis042910.php

Space is big, time is bunk

By Victor Allegretti

Douglas Adams once wrote, “There is a theory which states that if ever for any reason anyone discovers what exactly the Universe is for and why it is here it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another that states that this has already happened.”

A common problem with astrophysics is gravity’s insistence on non-conformity with the three other basic forces of nature: the strong and weak nuclear forces and electromagnetism. Dark energy also mischievously causes physicists to scratch their heads; it expands our universe at an accelerating rate, even though gravity should be contracting it or at least slowing the expansion.

While there isn’t any formal research to Douglas Adams’ statement, there is research from Nikodem Poplawski of Indiana University that postulates our universe exists inside of a black hole somewhere in space. He believes that the classic dark energy and gravity enigmas are the result of physicists commonly stopping their research for the origins of our universe at the Big Bang. According to Poplawski’s research, the collapse of a massive star in another universe could have created a wormhole, a space-time “bridge” (hence the name Einstein-Rosen bridges) to another point in space-time. Poplawski theorizes that within this wormhole, conditions could have existed similar to those associated with the Big Bang, thus possibly forming our universe.

The current conundrums of dark energy and non-conforming gravity can be addressed by this theory. If a universe existed prior to our own, it is possible that nuclear forces and electromagnetism played nice with gravity, and if our universe is expanding towards the end of the wormhole, the inexplicable expansion of our universe can be explained sans dark energy. Don’t be too excited to see whatever strange and bizarre cosmos exists beyond our own, however. The physics of wormholes are similar to the physics of black holes. If you could ever pass through the event horizon of the wormhole to visit the universe on the other side, you could never return. “You will be stuck,” Poplawksi says.

Hopefully Douglas Adams wasn’t right.

Sources:

Icelandic volcanoes spew Hydrofluoric acid… just one more reason why living on Earth is sometimes difficult.

By Marci Wills, April 18th, 2010

It seems that Earth is especially determined to show off its tricks this year. The ongoing eruption of Eyjafjallajokull (how do you pronounce that?) volcano in Iceland this week serves as yet another powerful reminder that we must organize our lives around the unpredictable workings of our planet. The continued cessation of air travel across Europe due to Eyjafjallajokull’s ash cloud is more than a slight inconvenience, but the research of Hildur Gestsdottir of the Institute of Archaeology in Rejkjavik suggests that the eruption may pose an even more severe threat. She believes that hydrofluoric acid emmitted from the Icelandic volcanoes has killed hundreds, if not thousands, of Europeans in previous severe eruptions.

Aerial view of the ash cloud over Eyjafjallajokull last Thursday

Iceland’s most devastating eruption of historic time was that of the offshore volcanic peak, Laki, in 1783. Laki spewed ash into the air over 8 full months and 10,000 Icelanders (roughly 1 in 5) died. Laki’s ash cloud altered European weather patterns, resulting in consecutively one of Europe’s hottest summers followed by its  most severe winter on record in 1873, both of which were associated with higher than normal death rates in Europe that year. Still, Hildur Gestsdottir believed that there were other reasons behind why the death toll in Iceland was so high. Survivors of the Laki eruption noted that their sheep and other livestock developed knobby protrusions from their bones, a telltale sign of fluorosis, or fluoride poisoning, just before dying. When Hildur excavated late 18th century graves in 2004, she found that many of those buried just after the eruption showed similarly abnormal bone growths. Hildur believes that these people were drinking water with concentrations of 30 to 40 ppm of hydrofluoric acid, enough to make you feel sick, but the poisoned ash was so pervasive that they simply had no other option.

The current Eyjafjallajokull eruption is not expected to reach a Laki-like scale. The ash cloud is located at ~30,000 ft, unfortunately the same altitude at which planes fly, but luckily below the stratosphere where volcanic gases can have a global effect because of a lack of rain there. Atmospheric scientist Brian Toon of the University of Colorado Boulder expects that the ash cloud from Eyjafjallajokull will be washed away by rain as it drifts further to the east. Still, hydrofluoric acid may become a worry if the eruption continues much longer. Fluoride-rich volcanic ash clings to vegetation and may affect crops and livestock even at low concentrations. If continuously ingested at high concentrations, people and animals can begin to die within several months. The effects of fluoride-rich volcanic ash are not fully understood as such Fluoride-rich lava is characteristic only of the volcanoes in Iceland and some in Melanesia.

Iceland has about 130 volcanoes, 18 of which have erupted since the settlement of the island in 900 C.E. Events of the scale of the Laki disaster are expected to occur there every 500 to 1000 years. As part of learning to survive on our planet, it is important to consider the challenges of keeping food and drinking water fluoride-free (and free of other various volcanic poisons) in the midst of air traffic, and possibly communication, shutdown due to volcanic eruptions.

Sources:

http://www.eurekalert.org/pub_releases/2010-04/uoca-vei041510.php

http://www.nytimes.com/2010/04/16/world/europe/16iht-scene.html

Stone, R., 2004, Iceland’s Doomsday Scenario: Science, News Focus, v. 306, p. 1278-1281.

Plant cancer leads a double life as a tailor

by Allison Younkins

“Corn Smut” is both a plant cancer and a tailor.  This maize fungus does not tailor clothes but it does tailor its genes to attack the host tissue it is infecting.  This April, researchers and Stanford unlocked some astonishing secrets about how corn smut manipulates genes in its genome to affect its host more severely.

The researchers used laboratory techniques such as DNA microarrays, which allowed them to seem which genes in the pathogen’s genome were activated.  What they found will inevitably change the way pathologist’s study plant pathogens and human cancers.  Their experiment showed that the pathogen had different active genes when it was infecting various parts of the plant including the seedlings or the adult leaves.  About 30% of the pathogen’s genome was activated no matter where the infection was located.  The activation of the remaining 70% varied depending on the location of the infection.  This phenomenon has been overlooked in the past because normally only tissues from one cell type are studied in an experiment.

These findings may allow scientists to return to pathogens retroactively and discover new information about the mechanism of plant diseases including corn smut.

This is a significant finding for the plan pathology community but it also has implications for human disorders.  Corn smut is a tumor-causing plant cancer, and researchers believe that information from this study could fuel new experiments in cancer research.  Their discoveries about this plant cancer suggest that diseases such as cancer can alter their genetic material to better infect a host.  If the activated genes can be targeted, this could create more specific treatments and medications for cancer.

Corn smut has traditionally been overlooked as a research interest because it does not devastate maize crops and is not harmful to humans who eat infected maize.  It is common in Mexico for the plant tumors to be used in food and can even be grown intentionally.  However, this seemingly unimportant pathogen may hold a wealth of information about how diseases attack their hosts and what we can do to stop them.

A maize tassel infected with corn smut. The tumors are the large white, bulbous growths, some of which have turned yellow or brown. Linda A. Cicero, Stanford University News Service

Want to hear a Stanford University researcher speak about her research on corn smut? Check out the link below

Plant Pathogen Tailors Attacks Genetically

Future Protection Found in the Past

By: Kate Good

As the world struggles to create “nature friendly” technology to compensate for our gas-guzzling vehicles and electricity needs, a major solution to global carbon increase has been overlooked. Collaborative research from forest scientists and over 13 universities suggests that the best way to combat global warming is by protecting indigenous lands

Deforestation of indigenous lands causes large amounts of carbon dioxide to be released into the atmosphere, by creating protected areas where the natural habitat is preserved, hundreds of thousands of tons of carbon dioxide will be prevented from entering into the global carbon cycle.

Described as a  “win-win” situation, the protection of indigenous lands will slow forest loss, conserve biodiversity while simultaneously preserving local cultures.

Industry and urbanization does not only pose a threat to natural environments, but cultural ones as well. While this approach seems to be a step backward in the movement to create new “green” technology, logically it makes the most sense.

Research shows that all of the indigenous lands and protected areas (ILPAs) in the world contain more than 312 billion tons of carbon. It is projected that the protected areas founded between 2003 and 2007 could prevent over one-third of the world’s annual greenhouse gas emissions of carbon dioxide from being released by 2050.

In areas such as Brazil, indigenous lands account for approximately four times the area of already existing national and state protected lands, however, without protection, these lands face the direct threat of deforestation.

Brazilian Rainforest

The expansion of industrial land as apposed to the establishment of protected natural areas is not only costly in the monetary sense but also environmentally. Rather than looking to assuage the damage caused by industrialization, efforts to protect and maintain indigenous lands holds a long-term benefit to the health of the environment.

Over the course of the December climate talks in Copenhage, developed countries agreed to financially support poor nations in protecting their forests from deforestation, however there is no governmental mechanism in existence to carry out these changes.

Sources:

http://www.nature.com/news/2010/100315/full/news.2010.123.html

Happy New-Geologic-Epoch!

By Marci Wills, April 4, 2010

Get out your party hats, because we may soon be welcoming in a new geologic epoch! Some scientists believe that humanity has affected the Earth so drastically over the past two centuries that changes may be significant enough to mark a new age of geologic time. Last week, earth scientists Jan Zalaseiwicz, Mark Williams (University of Leicester, UK), Will Steffen (Australian National University, Canberra), and Paul Crutzen (Max-Planck-Institute for Chemistry, Mainz, Germany) formally made the case for the addition of the “Anthropocene Epoch” to the Geologic Time Scale in the American Chemical Society’s journal, Environmental Science and Technology. More importantly, they warn that the Anthropocene could be accompanied by Earth’s next great mass extinction.

Evidence for the Anthropocene appears irrefutable from space

The Geologic Time Scale partitions 4.57 billion years of Earth’s history into four eras which contain shorter periods (For example, the Mesozoic era includes the Triassic, Jurassic, Cretaceous periods) and even finer epochs. Currently we live in the Holocene epoch which began ~11,000 years ago with the end of the most recent ice age.

Transitions between major divisions on the time scale are marked by observable changes in the sedimentary record worldwide. Usually, these are associated with upheavals in the planet’s climate and biodiversity. In their paper last week, the four scientists argue that “The scale of change taken place so far, or that is imminent or unavoidable, appears to have already taken the Earth out of the envelope of conditions and properties that mark the Holocene Epoch”

In addition to widely recognized changes in atmospheric composition, global temperature rise, melting polar ice, and rising sea levels, the study argues that many other human-induced effects are plainly visible on the Planet. Humans have brought about an order of magnitude increase in worldwide erosion rates, and the Anthropocene can be recognized by a variety of human-made sediment layers; the concrete of our roads and cities, the soils of our fields, and the polluted muds of estuaries, to name a few.

Most importantly, these scientists suspect that the Anthropocene may coincide with the world’s 6th mass-extinction event. Already, current extinction rates are estimated to be 100 to 1000 times greater than the normal background level and another 10-fold increase is expected this century.

The geologic time scale is overseen by multiple governing bodies under the International Union of Geological Sciences, all which will have to be convinced before “The Anthropocene” is officially adopted. But according to these four researchers, “However these debates unfold, the Anthropocene represents a new phase in the history of both humankind and of the Earth, when natural forces and human forces become intertwined, so that the fate of one determines the fate of the other. Geologically, this is a remarkable episode in the history of the planet”

Sources:

Zalasiewicz, J., Williams, M., Steffen, W., Crutzen, P., 2010, The new world of the Anthropocene: Environmental Science and Technology, v. 44, p. 2228-2231.

http://www2.le.ac.uk/ebulletin/news/press-releases/2010-2019/2010/03/nparticle.2010-03-26.0882152385

A Truly Sweet Deal

By: Kristen Kocher

Today, geneticists at Cold Spring Harbor Laboratory (CSHL) in New York and their colleagues at Hebrew University in Israel published a recent study about a genetic mutation in tomato plants. According to their research, a gene, called the florigen gene, has been isolated that has the ability to boost the yielding potential of tomato plants and controls when a plant matures and flowers. The harnessing of this gene is incredibly beneficial because it works in a variety of tomato plant species and across a range of environmental conditions.

So, why is this a sweet deal for farmers? Well, the gene would give farmers the ability to grow tomato plants year-round, greatly increasing the income of money of the agricultural market. Head researcher at CSHL, Zach Lippman, Ph.D, notes, “This discovery has potential to have a significant impact on both the billion-dollar tomato industry, as well as agricultural practices designed to get the most yield from other flowering crops.” To make this deal extra sweet, this gene also enhances the taste of the tomato, making it sweeter and more palatable than normal tomatoes. Normal, non-genetically modified tomato plants produce a limited amount of sugar that they equally distribute to their fruits. With the florigen gene, the amount of sugar produced in tomato plants increases, thus making the fruit produced sweeter and better tasting overall.

The discovery of the florigen gene came when the team at CSHL was searching for genes that initiate increased yield, or hybrid vigor. Hybrid vigor, or heterosis, is a breeding process in which two plants of different varieties are crossed to produce hybrid offspring with higher yields. Charles Darwin discovered heterosis over a century ago through the study of corn and rice crops. The CSHL lab team recently rediscovered heterosis and while the mechanism is largely still unknown, their research has provided some clues as to what the mechanism may be.  According to their findings, this phenomenon occurs due to a single gene that when present causes something called, “superdominance.”

The CSHL team tested many varieties of plant to identify if the florigen gene was superdominant, or always expressed when present. They catalogued a collection of 5,000 tomato plants and located single gene mutations that affect certain characteristics of the plant, such as fruit size and leaf shape. In this mutant library they noticed a trend among 60% of the plants that found a certain gene, the florigen gene, causes increased yield. According to a breakthrough publication in 2005, the florigen gene codes for the production of a certain protein, florigen, which is associated with the timing of maturation and flowering.

They believe that in tomato plants there is a delicate balance between the production of the florigen protein and another protein that controls plant development. Maturation, the 60% trend seen in tomato plants with a single gene mutation, still occurs when a single copy of the florigen gene is present, thus suggesting that it may have heterosis properties.

In the future, geneticists working on harnessing heterosis and improving crop yield have planned on researching the effects of the single gene mutation more fully. Lippman comments, “Mutant plants are usually thrown away because of the notion that mutations would have negative effects on growth… our results indicate that breeding with hybrid mutations could prove to be a powerful new way to increase yields, not only in tomato, but all crops.”

Check here for more information

Original Press Release

Breathing Underwater

By: Kate Good

Off the shore of Washington and Oregon low oxygen levels in the Pacific has caused the death of hundreds of Dungeness crabs.  Like mammals, underwater species need oxygen to survive. In a recent study, marine researchers at Oregon State believe that the temperature increase associated with global climate change is directly linked to lowering oxygen levels in oceans.

Causes of Hypoxia

Areas of hypoxia (lacking oxygen) are common in the deep ocean, however, it appears that areas in the Pacific, Atlantic and Indian oceans are spreading.  This phenomenon can be caused by the excess of nutrients within water, causing large increases of algae growth. As algae levels rise, the ability of sunlight to penetrate water decreases along with the amount of oxygen that can be dissolved. As algae die and breakdown they consume oxygen, if the oxygen is not replaced, the result is a dead zone.

Scientists believe that as water temperatures rise, the warm water on the surface acts as a cap, inhibiting the natural circulation patterns, disallowing deep waters from reaching the surface where it can be replenished with oxygen.

There is a delicate balance between upwelling and the ocean ecosystems, as this process provides many low dwelling species with oxygen. Scientists do not yet know the future implications that will follow with mass oxygen depletion. However, the large amount of dead Dungeness crab illustrates the dire consequences of oxygen depletion.

Marine Algae

Though hypoxia takes place in the deep ocean, humans play a large role in its occurrence.  After rain, or excessive watering, the fertilizers used on agricult

ural fields, golf courses, and suburban lawns runoff into lakes and streams that lead to major bodies of water.  The effect that fertilizer has on plants on land is the same with plants in the ocean, however, when underwater excessive plant growth has serious consequences.

Sources:

http://news.yahoo.com/s/mcclatchy/20100307/sc_mcclatchy/3444187_1;_ylt=Akn9Ml_HbwT6n4ol7reh6LzHSpZ4

http://toxics.usgs.gov/definitions/hypoxia.html

http://oceanservice.noaa.gov/products/pubs_hypox.html

Feb. 27th Chilean Earthquake no shock to geophysicists

By Marci Wills, March 6, 2010

A building damaged in Conception, Chile by the February 27th, 2010 earthquake

The enormous magnitude 8.7 earthquake which struck Chile last Saturday (February 27th) in startling proximity to the Haiti disaster has lead some of my friends and family to an apocalyptic level of speculation. They want to know what freak force of nature caused these earthquakes to occur so close together? But it is important to remember that earthquakes are a normal occurrence on Earth that can happen at any time. In fact, last week’s upheaval in Chile came as no surprise to the scientific community and to two geophysicists in particular who expected it to happen.

Jian Lin of the Woods Hole Oceanographic Institute (Woods Hole, MA) and Ross Stein of the United States Geological Survey (Menlo Park, CA), had anticipated an earthquake in the location of the Feb 27th event since the completion of their research in the region 6 years ago. In a paper published in the Journal of Geophysical Research in February of 2004, they warned that this area was at increased risk of a large earthquake due to after effects of the world’s largest recorded quake, a magnitude 9.5 event, which occurred in Chile in 1960.

Both the 1960 and 2010 Chilean earthquakes occurred just off the west coast of Chile along a tectonic plate boundary where the Nazca plate moves beneath the South American plate. Stress accumulates along this boundary until it is suddenly released by movement of the plates during an earthquake. The portion of the plate boundary that moves, called the earthquake’s rupture zone, can stretch hundreds of kilometers. Stress is relieved in this zone following an earthquake but it may increase elsewhere.

Jian Lin and Ross Stein used GPS measurements of tectonic plate motion to estimate changes in stress from the 1960 event and found that stress had greatly increased just north of the 1960 rupture. They predicted that this region would be the next portion of the plate boundary to produce a large earthquake in Chile. Sure enough, last Saturday  the 2010 earthquake picked up where the 1960 earthquake rupture left off.

This sort of progression also occurred after the December 26th, 2004 magnitude 9.0 earthquake in Sumatra, when it was followed by a magnitude 8.7 earthquake on the southern end of the rupture zone just 3 months later on March 28, 2005. “The only difference is that it took 50 years for the northern neighboring section of the 1960 [Chile] earthquake to rupture, while it took only 3 months for the southern adjacent segment to rupture in Sumatra”, Lin noted.

Lin believes that the Haiti earthquake similarly transferred stress further east along the Enriquillo Fault which broke on Jan. 12th, but it would have had no effect on the stress state in Chile.

Lin and Stein also used their method of measuring stress changes to assess which faults in the San Andreas region of southern California are most likely to move next, but only time will reveal the accuracy of their predictions there. It seems as though we are another step closer to understanding and anticipating earthquakes, rather than thinking of them as freak events.

Sources:

Lin, J, and Stein, R.S., 2004, Stress triggering in thrust and subduction earthquakes and stressinteraction between the southern San Andreas and nearby thrust and strike-slip faults: Journal of Geophysical Research, v. 109.

http://www.whoi.edu/page.do?pid=7545&tid=282&cid=69866&ct=162

Fluorescent supermarket lighting leaves spinach more nutritious than ever

Spinach on display under 24-hour light in supermarkets actually gains in content of some nutrients. (Marc Villalobos, USDA-ARS)

by Allison Younkins

Healthier spinach, just add light

Spinach, or Spinacia oleracea, is one of the most nutritious vegetables found in the grocery store.  Normally packaged in a clear plastic container, most spinach leaves are exposed to fluorescent supermarket lights for up to 24 hours a day.  Surprisingly, a study published in March in the Journal of Agricultural and Food Chemistry shows that the light exposure boosts the vegetable’s nutritional content to astonishing levels.  Scientists at the Kika de la Garza Subtropical Agricultural Research Center and the Atlantic Food and Horticulture Research Centre conducted an experiment to test the affect of lighting on the nutritional value of spinach.  They exposed spinach to either continuous light or darkness while under simulated supermarket storage conditions for up to 9 days.  Even spinach leaves exposed to the fluorescent lighting for only three days showed significant increases in important vitamins and antioxidants.  The leaves exposed to nine days of light had increased folate levels by 84-100% and levels of vitamin K between 50-100%.  Even further, the group exposed to no light had declining nutritional values.

How light contributes to nutrition: the connection

The main researcher on this project, Gene Lester of the USDA Agricultural Research Service, explains how supermarket lighting can contribute to vitamin and mineral levels within the leaves of this powerhouse plant.  Lester clarifies that although a leaf has been detached from the original plant, it can still undergo the process of photosynthesis.  The lighting in supermarkets allows the spinach leaves to continue creating vitamins and minerals as they would naturally.  Lester comments, “As long as there is moisture in the leaves and as long as there is gas exchange and light, it is good to go whether they are picked or not.”

How other vegetables and consumers can benefit from this study

The most exciting implication of these results is that other vegetables may receive the same benefits from fluorescent lighting.  Keeping vegetables fresh in grocery stores is a constant struggle, and additional studies may illuminate more effective storage solutions.  One serving of spinach currently provides 20% of your daily recommendation for vitamins C, A, B9, K, and E but with further research soon you may be getting more bang for your nutritional buck!

Want to learn more? Check out the resources I used for this blog:

Supermarket lighting enhances nutrient level of fresh spinach

Want fresh veggies? Let there be light!