Oct 15, 2015 05:23 PM
Castles, Kings, and Ice: A Whirlwind Tour of Latvian Geology
EXCERPT: Our own RQ tormented me a little bit this summer. She kept sending nifty tidbits of geology from her summer excursions in Latvia. And she's got lots! By popular demand, we're going to have a super-swift overview of Latvian geologic yumminess, with the promise of more where that comes from....
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The Hayward Fault: Overdue for Destruction
EXCERPT: [...] On October 21, 1868, a magnitude 7.0 earthquake occurred on the Hayward Fault in the East Bay. A lesser-known cousin of the San Andreas Fault, the Hayward Fault is a crack in the earth’s crust up to 20 miles deep that stretches roughly 70 miles from San Pablo Bay in the north to Fremont and Milpitas at its southernmost end. In 1868, the towns of Hayward, San Leandro and Fremont were hardest hit. Luckily, the area had a population of only about 1000 people at the time. Still, 30 people died in the 1868 earthquake and hundreds of buildings from the East Bay to San Francisco to Gilroy were destroyed.
Research has shown that the last five big earthquakes on the Hayward Fault back to the year 1315 have occurred on average every 140 years. It has now been 147 years since the last big one. And today, more than 2.5 million people live within a stone’s throw of the Hayward Fault, including in densely populated areas like downtown Oakland. According to the U.S. Geological Survey’s 2015 statewide earthquake forecast, for every year that passes without a significant seismic event, the chance of another massive earthquake on the Hayward Fault increases....
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Could contaminated land actually be good for trees?
RELEASE: The very act of tolerating some forms of soil pollution may give trees an advantage in the natural world, says University of Montreal plant biologists. Their findings were published this week in BMC Plant Biology.
High chemical tolerant plants can be used to rehabilitate land contaminated with heavy metals or petroleum by-products -- some 30,000 such sites exist in Canada and 342,000 sites in Europe -- through a process termed phytoremediation. The research team compared the molecular response of willow trees growing in contaminated or non-contaminated soil and found that several plant genes were expressed differently between both treatments. "The most fascinating result, however, comes from the fact that genetic information (RNA) from other organisms, such as fungi, bacteria and insects were also found to be expressed differentially in plant tissues. Notably, 99% of RNA from spider mites, a common plant pest, was in higher abundance in trees growing without contamination," explained Nicolas Brereton, co-first author of the study. "This suggests that trees growing in contaminated soils might have reacted in a way that makes them less prone to herbivore attacks by priming their defense machinery."
Decontamination of polluted sites, often many hectares in scale, is costly and in itself can have a high environmental impact. "Phytoremediation plants must have a very high tolerance to pollution as well as high biomass yields. This second trait brings an additional value stream to the process of phytoremediation, outside of the direct benefit of rejuvenating land" Brereton said. Short rotation coppice willow are some of the highest yielding trees, having the ability to produce very large amounts of wood in temperate regions in a very short time and requiring low nitrogen fertilization. "By producing high yields we can use the produced biomass, for example wood, for processes such as lignocellulosic bioenergy production. We term the integration of these two complementary benefits added-value cultivation."
The genetic information exchange the researchers identified is in step with a new field in biology which has rapidly expanded since the advent of modern next-generation genetic sequencing technology: the systems biology approach relating to the "metaorganism." The researchers, directed by Michel Labrecque, Frederic Pitre and Simon Joly, look at all the interacting organisms as a single, dynamic biological entity in order to understand natural complexity. "One of the major discoveries we've been exploring is that when you extract genetic information from any plant tissue, such as RNA, you always also find genetic information from fungi, bacteria and even animals, such as insects and arachnids. In this case, the tree's defense against contamination, which is an abiotic stress, improves resistance to spider mites, a biotic stress," said Emmanuel Gonzalez, co-first author of the study. "The important point here is that genes have been switched on across multiple interacting organisms. This is what we call meta-transcriptomics, meta referring to metaorganism and transcriptome to the activation of genes. The ability to get such a comprehensive snapshot of genetics is very new. While cross-tolerance is known to occur in trees, it has yet to be documented in a phytoremediation context and certainly not using this cutting-edge next-generation sequencing technology."
While the researchers' early experiments were conducted in greenhouses, they are now in the process of repeating the work on mature crop trees grown in real contaminated sites. "We've already found similar interactions with arachnids and insects, the numbers of interacting organisms, especially fungi, are extraordinary high, often in the hundreds, for a given plant tissue if grown outside the laboratory," Gonzalez said.
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Ancient alga knew how to survive on land before it left water and evolved into the first plant
RELEASE: The team of scientists from the John Innes Centre, the University of Wisconsin -- Madison and other international collaborators, has discovered how an ancient alga was able to inhabit land, before it went on to evolve into the world's first plant and colonise the earth.
Up until now it had been assumed that the alga evolved the capability to source essential nutrients for its survival after it arrived on land by forming a close association with a beneficial fungi called arbuscular mycorrhiza (AM), which still exists today and which helps plant roots obtain nutrients and water from soil in exchange for carbon. The previous discovery of 450 million year old fossilised spores similar to the spores of the AM fungi suggests this fungi would have been present in the environment encountered by the first land plants. Remnants of prehistoric fungi have also been found inside the cells of the oldest plant macro-fossils, reinforcing this idea. However, scientists were not clear how the algal ancestor of land plants could have survived long enough to mediate a quid pro quo arrangement with a fungi. This new finding points to the alga developing this crucial capability while still living in the earth's oceans!
Dr Delaux and colleagues analysed DNA and RNA of some of the earliest known land plants and green algae and found evidence that their shared algal ancestor living in the Earth's waters already possessed the set of genes, or symbiotic pathways, it needed to detect and interact with the beneficial AM fungi.
The team of scientists believes this capability was pivotal in enabling the alga to survive out of the water and to colonise the earth. By working with the fungi to find sustenance, the alga was able to buy time to adapt and evolve in a very different and seemingly infertile environment.
Dr Delaux said: "At some point 450 million years ago, alga from the earth's waters splashed up on to barren land. Somehow it survived and took root, a watershed moment that kick-started the evolution of life on earth. Our discovery shows for the first time that the alga already knew how to survive on land while it was still in the water. Without the development of this pre-adapted capability in alga, the earth could be a very different place today.
"This finding has filled a gap in our collective knowledge about the origins of life on earth. None of this would have been possible without the dedication of a world-wide team of scientists including a tremendous contribution from the 1KP initiative led by Gane KS Wong ."
Professor Jean-Michel Ané, from the University of Wisconsin said: "The surprise was finding the mechanisms in algae which allow plants to interact with symbiotic fungi. Nobody has studied beneficial associations in these algae."
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EXCERPT: Our own RQ tormented me a little bit this summer. She kept sending nifty tidbits of geology from her summer excursions in Latvia. And she's got lots! By popular demand, we're going to have a super-swift overview of Latvian geologic yumminess, with the promise of more where that comes from....
- - - - - - -
The Hayward Fault: Overdue for Destruction
EXCERPT: [...] On October 21, 1868, a magnitude 7.0 earthquake occurred on the Hayward Fault in the East Bay. A lesser-known cousin of the San Andreas Fault, the Hayward Fault is a crack in the earth’s crust up to 20 miles deep that stretches roughly 70 miles from San Pablo Bay in the north to Fremont and Milpitas at its southernmost end. In 1868, the towns of Hayward, San Leandro and Fremont were hardest hit. Luckily, the area had a population of only about 1000 people at the time. Still, 30 people died in the 1868 earthquake and hundreds of buildings from the East Bay to San Francisco to Gilroy were destroyed.
Research has shown that the last five big earthquakes on the Hayward Fault back to the year 1315 have occurred on average every 140 years. It has now been 147 years since the last big one. And today, more than 2.5 million people live within a stone’s throw of the Hayward Fault, including in densely populated areas like downtown Oakland. According to the U.S. Geological Survey’s 2015 statewide earthquake forecast, for every year that passes without a significant seismic event, the chance of another massive earthquake on the Hayward Fault increases....
- - - - - - -
Could contaminated land actually be good for trees?
RELEASE: The very act of tolerating some forms of soil pollution may give trees an advantage in the natural world, says University of Montreal plant biologists. Their findings were published this week in BMC Plant Biology.
High chemical tolerant plants can be used to rehabilitate land contaminated with heavy metals or petroleum by-products -- some 30,000 such sites exist in Canada and 342,000 sites in Europe -- through a process termed phytoremediation. The research team compared the molecular response of willow trees growing in contaminated or non-contaminated soil and found that several plant genes were expressed differently between both treatments. "The most fascinating result, however, comes from the fact that genetic information (RNA) from other organisms, such as fungi, bacteria and insects were also found to be expressed differentially in plant tissues. Notably, 99% of RNA from spider mites, a common plant pest, was in higher abundance in trees growing without contamination," explained Nicolas Brereton, co-first author of the study. "This suggests that trees growing in contaminated soils might have reacted in a way that makes them less prone to herbivore attacks by priming their defense machinery."
Decontamination of polluted sites, often many hectares in scale, is costly and in itself can have a high environmental impact. "Phytoremediation plants must have a very high tolerance to pollution as well as high biomass yields. This second trait brings an additional value stream to the process of phytoremediation, outside of the direct benefit of rejuvenating land" Brereton said. Short rotation coppice willow are some of the highest yielding trees, having the ability to produce very large amounts of wood in temperate regions in a very short time and requiring low nitrogen fertilization. "By producing high yields we can use the produced biomass, for example wood, for processes such as lignocellulosic bioenergy production. We term the integration of these two complementary benefits added-value cultivation."
The genetic information exchange the researchers identified is in step with a new field in biology which has rapidly expanded since the advent of modern next-generation genetic sequencing technology: the systems biology approach relating to the "metaorganism." The researchers, directed by Michel Labrecque, Frederic Pitre and Simon Joly, look at all the interacting organisms as a single, dynamic biological entity in order to understand natural complexity. "One of the major discoveries we've been exploring is that when you extract genetic information from any plant tissue, such as RNA, you always also find genetic information from fungi, bacteria and even animals, such as insects and arachnids. In this case, the tree's defense against contamination, which is an abiotic stress, improves resistance to spider mites, a biotic stress," said Emmanuel Gonzalez, co-first author of the study. "The important point here is that genes have been switched on across multiple interacting organisms. This is what we call meta-transcriptomics, meta referring to metaorganism and transcriptome to the activation of genes. The ability to get such a comprehensive snapshot of genetics is very new. While cross-tolerance is known to occur in trees, it has yet to be documented in a phytoremediation context and certainly not using this cutting-edge next-generation sequencing technology."
While the researchers' early experiments were conducted in greenhouses, they are now in the process of repeating the work on mature crop trees grown in real contaminated sites. "We've already found similar interactions with arachnids and insects, the numbers of interacting organisms, especially fungi, are extraordinary high, often in the hundreds, for a given plant tissue if grown outside the laboratory," Gonzalez said.
- - - - - - -
Ancient alga knew how to survive on land before it left water and evolved into the first plant
RELEASE: The team of scientists from the John Innes Centre, the University of Wisconsin -- Madison and other international collaborators, has discovered how an ancient alga was able to inhabit land, before it went on to evolve into the world's first plant and colonise the earth.
Up until now it had been assumed that the alga evolved the capability to source essential nutrients for its survival after it arrived on land by forming a close association with a beneficial fungi called arbuscular mycorrhiza (AM), which still exists today and which helps plant roots obtain nutrients and water from soil in exchange for carbon. The previous discovery of 450 million year old fossilised spores similar to the spores of the AM fungi suggests this fungi would have been present in the environment encountered by the first land plants. Remnants of prehistoric fungi have also been found inside the cells of the oldest plant macro-fossils, reinforcing this idea. However, scientists were not clear how the algal ancestor of land plants could have survived long enough to mediate a quid pro quo arrangement with a fungi. This new finding points to the alga developing this crucial capability while still living in the earth's oceans!
Dr Delaux and colleagues analysed DNA and RNA of some of the earliest known land plants and green algae and found evidence that their shared algal ancestor living in the Earth's waters already possessed the set of genes, or symbiotic pathways, it needed to detect and interact with the beneficial AM fungi.
The team of scientists believes this capability was pivotal in enabling the alga to survive out of the water and to colonise the earth. By working with the fungi to find sustenance, the alga was able to buy time to adapt and evolve in a very different and seemingly infertile environment.
Dr Delaux said: "At some point 450 million years ago, alga from the earth's waters splashed up on to barren land. Somehow it survived and took root, a watershed moment that kick-started the evolution of life on earth. Our discovery shows for the first time that the alga already knew how to survive on land while it was still in the water. Without the development of this pre-adapted capability in alga, the earth could be a very different place today.
"This finding has filled a gap in our collective knowledge about the origins of life on earth. None of this would have been possible without the dedication of a world-wide team of scientists including a tremendous contribution from the 1KP initiative led by Gane KS Wong ."
Professor Jean-Michel Ané, from the University of Wisconsin said: "The surprise was finding the mechanisms in algae which allow plants to interact with symbiotic fungi. Nobody has studied beneficial associations in these algae."
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