Navigation Links
River plants may play major role in health of ocean coastal waters
Date:1/29/2008

ter flows into and through a plant canopy, and how long it remains within the canopycan be used to find the right balance between canopy and flow in a river.

Vegetation generates resistance to flow, so the velocity within a canopy is much less than the velocity above it. This spatial gradient of velocity, or shear, produces a coherent swirl of water motion, called a vortex. Using scaled physical models, Nepf and Ghisalberti described the dynamic nature of these vortices and developed predictive models for canopy flushing that fit available field observations. The team showed that vortices control the flushing of canopies by controlling the exchange of fluid between the canopy and overflowing water. Similar vortices also form at the edge of a vegetated channel, setting the exchange between the channel and the vegetation.

The structure and density of the canopy controls the extent to which flow is reduced in the canopy and also the water-renewal time, which ranges from minutes to hours for typical submerged canopies. These timescales are comparable to those measured in much-studied underground hyporheic zones, suggesting that channel vegetation could play a role similar to these zones in nutrient retention. In dense canopies, the larger vortices cannot penetrate the full canopy height. Water renewal in the lower canopy is controlled by much smaller turbulence generated by individual stems and branches.

We now understand more precisely how water moves through and around aquatic canopies, and know that the vortices control the water renewal and momentum exchange, said Nepf. Knowing the timescale over which water is renewed in a bed, and knowing the degree to which currents are reduced within the beds help researchers determine how the size and shape of a canopy will impact stream restoration.


'/>"/>
Contact: Denise Brehm
brehm@mit.edu
617-253-8069
Massachusetts Institute of Technology, Department of Civil and Environmental Engineering
Source:Eurekalert

Page: 1 2

Related biology news :

1. Baiji Dolphin previously thought extinct spotted in the Yangtze River
2. UC Riverside biologist receives prestigious MacArthur Fellowship
3. International team of scientists warns of climate changes impact on global river flow
4. Stronger EPA leadership needed to improve water quality in Mississippi River
5. UC-Riverside partners with Chinese university to address Chinas environmental problems
6. X-effect: female chromosome confirmed a prime driver of speciation
7. Tiny fish can yield big clues to Delaware River health
8. Scientists from the UGR prove that rivers do not act as barriers for groundwater flow
9. More comprehensive analysis of Klamath River basin needed to aid decision makers
10. Chemicals used as fire retardants could be harmful, UC-Riverside researchers say
11. LSU, Yale team study agricultural impact on Mississippi River
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:9/19/2014)... study the unique bioelectric signaling system of the electric ... The OU researcher is working to understand how ... signals used to map the world around them. ... 500-600 discharges a second throughout their lives. The ... but necessary for survival. , "There is evidence that ...
(Date:9/19/2014)... , Sept. 19, 2014 Nxt-ID, Inc. (Nasdaq: ... company focused on the growing m-commerce market, updates the "Wocket in ... in the lightweight and light middleweight weight classes, Vinny Pazienza ... was announced that Game of Thrones actor Ciaran ... with Children star Katey Sagal have been cast ...
(Date:9/18/2014)... located deep in the primitive brainstem has revealed how ... Harvard School of Medicine and the University at Buffalo ... the second "sleep node" identified in the mammalian brain ... to produce deep sleep. , Published online in August ... fully half of all of the brain,s sleep-promoting activity ...
Breaking Biology News(10 mins):NXT-ID's Vinny Paz Celebrity Ad Wocket Update: Katey Sagal and Ciaran Hinds Attached to His Upcoming Movie 2NXT-ID's Vinny Paz Celebrity Ad Wocket Update: Katey Sagal and Ciaran Hinds Attached to His Upcoming Movie 3No sedative necessary: Scientists discover new 'sleep node' in the brain 2
... a huge portion of real estate in western North ... and fossils very different from those in adjacent terranes. ... tectonic styles, metamorphism, and volcanic origins, much like the ... new Geological Society of America Special Paper brings together ...
... Washington, DCMay 28, 2008The 2008 American Society for ... Diagnostic Immunology is presented to Steven A. Rosenberg, ... Surgery, Uniformed Services University of the Health Sciences, ... of Medicine and Health Sciences. Sponsored by Abbott ...
... for Microbiology (ASM) Merck Irving S. Sigal Memorial Award ... Genetics and Microbiology, University of Texas at Austin. Sponsored ... Memorial Award is presented in memory of Irving S. ... therapies to treat HIV/AIDS, to recognize excellence in basic ...
Cached Biology News:American Society for Microbiology honors Steven A. Rosenberg 2
(Date:9/18/2014)... LONDON , Sept. 18, 2014 ... near-patient testing, is performed outside a clinical laboratory. ... hence in administrating appropriate treatments and medication. POCT ... and prevalence of lifestyle diseases such as diabetes, ... and user-friendly. POCT devices are standardized to minimize ...
(Date:9/18/2014)... 2014 Texas Governor Rick Perry, ... A&M Health Science Center CEO Brett Giroir, M.D., ... and Human Services (HHS), State of Texas and ... influenza vaccine manufacturing facility in Bryan, Texas, which ... the Texas A&M Biocorridor – a rapidly evolving ...
(Date:9/18/2014)... DUBLIN , Sept. 18, 2014 ... the "Global Companion Diagnostics (Polymerase Chain Reaction, In-situ ... report to their offering. The ... a CAGR of 22.7% from 2014 to 2019. Factors ... treatment, growing adoption of companion diagnostics by the pharmaceutical ...
(Date:9/18/2014)... SEATTLE , Sept. 18, 2014 /PRNewswire/ - Oncothyreon ... pricing of previously announced concurrent but separate underwritten offerings ... price to the public of $2.00 per share, for ... of its Series A Convertible Preferred Stock at a ... expected gross proceeds of $20 million. Each share of ...
Breaking Biology Technology:POCT Market in China 2014-2018 2Texas A&M Dedicates National Pandemic Influenza Vaccine Manufacturing Facility, on Track for 2016 Start-Up Phase 2Texas A&M Dedicates National Pandemic Influenza Vaccine Manufacturing Facility, on Track for 2016 Start-Up Phase 3Texas A&M Dedicates National Pandemic Influenza Vaccine Manufacturing Facility, on Track for 2016 Start-Up Phase 4Global Companion Diagnostics (Polymerase Chain Reaction, In-situ hybridization, Immunohistochemistry) Market - Trends & Forecasts to 2019 2Global Companion Diagnostics (Polymerase Chain Reaction, In-situ hybridization, Immunohistochemistry) Market - Trends & Forecasts to 2019 3Oncothyreon Prices $40 Million Concurrent Public Offerings of Common Stock and Preferred Stock 2Oncothyreon Prices $40 Million Concurrent Public Offerings of Common Stock and Preferred Stock 3
... was involved in the cloning of Dolly the sheep said ... coverage of embryonic stem cell research, which could be raising ... corner when they are at least a few years away. ... said news of the possibilities of human embryonic stem cell ...
... their best mind you, growing up was "Aftermath", an appropriate label ... 2006- Chicago. , ,As BIO 2006 - Chicago is still fresh ... the outcome, but so many others have already done so that ... more of the facts emerge (like the final attendance number). Suffice ...
... - A young company with a preventive solution to identity ... G. Steven Burrill Technology Business Plan Competition, but if area ... they better act quickly. , , Din and Newport ... plan. Khaja M. Din, president IPIC (Internet ...
Cached Biology Technology:Researchers say scientific reporting needs more perspective, less hype 2Researchers say scientific reporting needs more perspective, less hype 3BIO 2006 aftermath and a taste of bio-generics 2BIO 2006 aftermath and a taste of bio-generics 3BIO 2006 aftermath and a taste of bio-generics 4BIO 2006 aftermath and a taste of bio-generics 5BIO 2006 aftermath and a taste of bio-generics 6BIO 2006 aftermath and a taste of bio-generics 7BIO 2006 aftermath and a taste of bio-generics 8Winner of Burrill competition courted by North Carolina investors 2Winner of Burrill competition courted by North Carolina investors 3
... an expertise in the forefront of chemical ... synthesis and synthesis in solution. , Our ... and analytical HPLC at no extra cost, ... the highest quality standard. , Our team ...
The Wellwash 4 Mk 2 microplate washer combines flexibility, simplicity and ease of use. This reliable microplate washer meets the exacting standards of today's ELISA assay requirements....
... dispensers save space and organize gloves, ... garb. They are the perfect benchtop ... in labs, processing and manufacturing. Clear ... the particles they attract. Many other ...
... These handy dispensers save space ... wipers, hats, and other garb. ... storage bins for small parts ... manufacturing. Clear acrylic. Many other ...
Biology Products: