Tidal marshes cover only about 45,000 square kilometers worldwide--about the area of Denmark. In comparison with other habitats, tidal marshes support few nonaquatic vertebrate species, but their unique characteristics have led to the evolution of species and subspecies that are endemic (found nowhere else).
These endemic species and subspecies, which seem to be largely restricted to North America, have adaptations that suit them to life in a harsh environment in which seed abundance is low, salinity is high, and flooding is frequent. Yet they face a broad variety of threats from human-caused environmental damage, according to an assessment in the August 2006 issue of BioScience written by Russell Greenberg of the Smithsonian Migratory Bird Center and colleagues.
Tidal marshes occur in mid to high latitudes, along coasts that are protected within estuaries or behind barrier islands. They are most common in North America and China. Some tidal marsh species are protected from high salinity by relatively impermeable skin, and others have kidneys that can concentrate salts from large volumes of water or specialized glands that exude salt. Many are gray or black in color, which is believed to be an advantage because it matches the dark color of the soils often found in tidal marshes. Why endemic tidal marsh species seem to be largely restricted to North America--which has 24 of the worldwide total of 25--is not clear. Although it could reflect differing taxonomic practices in different countries, it may be related to the history of glaciation or of agriculture.
Endemic tidal marsh species are vulnerable to coastal development and to sea level rise, both of which are rapidly reducing the area of tidal marshes. They are also threatened by toxic wastes and invasive species. Greenberg and his coauthors argue for an expanded research program to try to understand how species will respond to these threats.
BioScience publishes commentary and peer-reviewed articles covering a wide range of biological fields, with a focus on Organisms from Molecules to the Environment. The journal has been published since 1964 by the American Institute of Biological Sciences, an umbrella organization for professional scientific societies and organizations that are involved with biology. It represents some 200 member societies and organizations with a combined membership of about 250,000.
Donna Royston | EurekAlert!
Scientists team up on study to save endangered African penguins
16.11.2017 | Florida Atlantic University
Climate change: Urban trees are growing faster worldwide
13.11.2017 | Technische Universität München
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
22.11.2017 | Business and Finance
22.11.2017 | Physics and Astronomy
22.11.2017 | Physics and Astronomy