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Full-Text Articles in Life Sciences

Standard-Level Herbivory In An Old-Growth Conifer Forest Canopy, David C. Shaw, Kristina A. Ernest, H. Bruce Rinker, Margaret D. Lowman Dec 2006

Standard-Level Herbivory In An Old-Growth Conifer Forest Canopy, David C. Shaw, Kristina A. Ernest, H. Bruce Rinker, Margaret D. Lowman

All Faculty Scholarship for the College of the Sciences

Herbivory is an important ecological process in forest canopies but is difficult to measure, especially for whole stands. We used the Wind River Canopy Crane in Washington State to access 101 randomly-located sample points throughout the forest canopy. This provided a relatively quick and convenient way to estimate herbivory for a whole stand. The overall level of herbivory was estimated at 1.6% of leaf area. The distribution was strongly skewed to the lower canopy where broad-leafed species experienced higher levels of herbivory. Herbivory averaged 0.3% in conifers and 13.5% in broad-leafed species. Fully half of the sample points had no …


Distance-Based Genome Rearrangement Phylogeny, Li-San Wang, Tandy Warnow, Bernard M.E. Moret, Robert K. Jansen, Linda A. Raubeson Oct 2006

Distance-Based Genome Rearrangement Phylogeny, Li-San Wang, Tandy Warnow, Bernard M.E. Moret, Robert K. Jansen, Linda A. Raubeson

All Faculty Scholarship for the College of the Sciences

Evolution operates on whole genomes through direct rearrangements of genes, such as inversions, transpositions, and inverted transpositions, as well as through operations, such as duplications, losses, and transfers, that also affect the gene content of the genomes. Because these events are rare relative to nucleotide substitutions, gene order data offer the possibility of resolving ancient branches in the tree of life; the combination of gene order data with sequence data also has the potential to provide more robust phylogenetic reconstructions, since each can elucidate evolution at different time scales. Distance corrections greatly improve the accuracy of phylogeny reconstructions from DNA …


Perchlorate And Nitrate Remediation Efficiency And Microbial Diversity In A Containerized Wetland Bioreactor, Paula Krauter, Bill Daily Jr., Valerie Dibley, Holly Pinkart, Tina Legler Aug 2006

Perchlorate And Nitrate Remediation Efficiency And Microbial Diversity In A Containerized Wetland Bioreactor, Paula Krauter, Bill Daily Jr., Valerie Dibley, Holly Pinkart, Tina Legler

All Faculty Scholarship for the College of the Sciences

We have developed a method to remove perchlorate (14–27 μg/L) and nitrate (48 mg/L) from contaminated groundwater using a wetland bioreactor. The bioreactor has operated continuously in a remote field location for more than 2 yr with a stable ecosystem of indigenous organisms. This study assesses the bioreactor for long-term perchlorate and nitrate remediation by evaluating influent and effluent groundwater for oxidation-reduction conditions and nitrate and perchlorate concentrations. Total community DNA was extracted and purified from 10-g sediment samples retrieved from vertical coring of the bioreactor during winter. Analysis by denaturing gradient gel electrophoresis of short, 16S rDNA, polymerase-chain-reaction products …


Photoreductive Dissolution Of Ferrihydrite By Methanesulfinic Acid: Evidence Of A Direct Link Between Dimethylsulfide And Iron-Bioavailability, Anne M. Johansen, Jennifer M. Key Jul 2006

Photoreductive Dissolution Of Ferrihydrite By Methanesulfinic Acid: Evidence Of A Direct Link Between Dimethylsulfide And Iron-Bioavailability, Anne M. Johansen, Jennifer M. Key

All Faculty Scholarship for the College of the Sciences

Within open‐ocean regions where excess macronutrients are present, phytoplankton growth is limited by the bioavailability of iron supplied to these areas primarily within atmospheric aerosols of crustal origin. However, processes that control the abundance of biologically accessible iron in these aerosols are largely unknown. Here we show that dissolution of ferrihydrite, a surrogate iron(oxy)hydroxide phase found in atmospheric waters, is enhanced in the presence of methanesulfinic acid (MSIA, CH3SO2H, a dimethylsulfide (DMS) oxidation intermediate) in laboratory irradiation experiments with aqueous suspensions that simulate marine aerosol particles. The increased release of soluble Fe(II) is attributed to a …


The Effect Of Male Competition On Female Choice In Brandt’S Vole, Lasiopodomys Brandti, Jianjun Zhang, Dazhao Shi, Lixing Sun Jun 2006

The Effect Of Male Competition On Female Choice In Brandt’S Vole, Lasiopodomys Brandti, Jianjun Zhang, Dazhao Shi, Lixing Sun

All Faculty Scholarship for the College of the Sciences

The effect of male competition on female choice in the Brandt’s vole (Lasiopodomys brandti) was studied in the laboratory. Using a two-way choice test, we showed that when males did not compete, estrous females preferred and mated with the dominant males, but non-estrous females preferred subordinate males. However, when males competed, all dominant males gained the priority to mate, and the amicable behaviour between males, regardless of their dominant status, and between non-estrous females increased, compared with the behaviour between males and the estrous females. These results showed that interactions among Brandt’s voles were not only influenced by …


Effects Of Ultraviolet-B Radiation On Leaf Morphology Of Arabidopsis Thaliana (L.) Heynh. (Brassicaceae), Maria Regina Torres Boeger, Mary E. Poulson Jun 2006

Effects Of Ultraviolet-B Radiation On Leaf Morphology Of Arabidopsis Thaliana (L.) Heynh. (Brassicaceae), Maria Regina Torres Boeger, Mary E. Poulson

Biology Faculty Scholarship

Reduction of the ozone layer results in the increase in ultraviolet radiation reaching the earth's surface, especially the ultraviolet-B (UV-B). The increase of radiation may induce structural and physiological changes in plants, influencing their growth and development. This paper evaluates the effects of ambient UV-B radiation upon to the leaf morphology of Arabidopsis thaliana developed under controlled conditions. The seeds of A. thaliana grown in environmental chamber, with 300 µmol m-2s-1 de photosynthetically active radiation (PAR) with and without 6 kJ m-2 s-1 of radiation UV-Bbe (UV-Bbe; UV-B biologically effective). After 21 …


Efeitos Da Radiação Ultravioleta-B Sobre A Morfologia Foliar De Arabidopsis Thaliana (L.) Heynh. (Brassicaceae), Maria Regina Torres Boeger, Mary Poulson Jan 2006

Efeitos Da Radiação Ultravioleta-B Sobre A Morfologia Foliar De Arabidopsis Thaliana (L.) Heynh. (Brassicaceae), Maria Regina Torres Boeger, Mary Poulson

Biology Faculty Scholarship

Reduction of the ozone layer results in the increase in ultraviolet radiation reaching the earth’s surface, especially the ultraviolet-B (UV-B). The increase of radiation may induce structural and physiological changes in plants, influencing their growth and development. This paper evaluates the effects of ambient UV-B radiation upon to the leaf morphology of Arabidopsis thaliana developed under controlled conditions. The seeds of A. thaliana grown in environmental chamber, with 300 μmol m-2s-1 de photosynthetically active radiation (PAR) with and without 6 kJ m-2 s-1 of radiation UV-Bbe (UV-Bbe; UV-B biologically effective). After 21 days, ten leaves of each treatment (with and …