Pan et al. claim that our results actually support a strong linear positive relationship between productivity and richness, whereas Fridley et al. contend that the data support a strong humped relationship. These responses illustrate how preoccupation with bivariate patterns distracts from a deeper understanding of the multivariate mechanisms that control...
Studies of experimental grassland communities¹⁻⁷ have demonstrated
that plant diversity can stabilize productivity through species
asynchrony, in which decreases in the biomass of some species
are compensated for by increases in others[superscript 1,2]. However, it remains
unknown whether these findings are relevant to natural ecosystems,
especially those for which species...
Human alterations to nutrient cycles[superscript 1,2] and herbivore communities³⁻⁷
are affecting global biodiversity dramatically². Ecological theory predicts
these changes should be strongly counteractive: nutrient addition
drives plant species loss through intensified competition for
light, whereas herbivores prevent competitive exclusion by increasing
ground-level light, particularly in productive systems[superscript 8,9]. Here we...
Exotic species dominate many communities; however the functional significance of species’ biogeographic origin remains highly contentious. This debate is fuelled in part by the lack of globally replicated, systematic data assessing the relationship between species provenance, function and response to perturbations. We examined the abundance of native and exotic plant...
Invasions have increased the size of regional species pools, but are typically assumed to reduce native diversity.
However, global-scale tests of this assumption have been elusive because of the focus on exotic species richness,
rather than relative abundance. This is problematic because low invader richness can indicate invasion resistance by...
Full Text:
X
Charles Mitchell
X X
JoslinL. Moore
X X
John Morgan
X X
Brent
Invasions have increased the size of regional species pools, but are typically assumed to reduce native diversity.
However, global-scale tests of this assumption have been elusive because of the focus on exotic species richness,
rather than relative abundance. This is problematic because low invader richness can indicate invasion resistance by...
Full Text:
MCCULLEY 4 0 ,
BRETT MELBOURNE 4 , CHARLES E . M ITCHELL 4 1 , JO SL IN L . MOORE 4 2 , JOHN MORGAN4 3
Invasions have increased the size of regional species pools, but are typically assumed to reduce native diversity. However, global-scale tests of this assumption have been elusive because of the focus on exotic species richness, rather than relative abundance. This is problematic because low invader richness can indicate invasion resistance by...
Two mathematical computer games, POE and EQUATIONS, were used to
test the effects of games as learning aids in a university entry-level
intermediate algebra course. Specifically, this study investigated
whether use of these games would significantly increase student achievement
in the course and improve student attitude toward mathematics.
EQUATIONS is...
Twenty-one women, lifelong residents of Xichang County, Sichuan Province, China, an area of very low soil selenium (Se), received tablets containing either 100 μg Se daily as Se-enriched yeast (+Se) or no additional Se (-Se), throughout the last trimester of pregnancy and the first three months of lactation. Diet was...
Grafted grapevines will become increasingly important in Oregon vineyards in order to prevent loss of plants to phylloxera infestations. Several rootstocks are now being evaluated in Oregon for horticultural traits and characteristics related to wine quality. Resistance or tolerance to other plant diseases affecting grapevines needs to be examined as...
Oregon is a leader in production of premium wines in the United States and the industry has been expanding rapidly over the past few years. However, continued production and expansion of vineyards are threatened by infestation of phylloxera, Daktulospaira vitifoliae, an insect that feeds on roots. Most grapevines in Oregon...
Hop (Humulus lupulus L.) cones are used extensively in beer brewing to enhance flavor and impart bittering. Verifying hops cultivar identity has traditionally been accomplished by morphological characteristics or a chemical analysis of lupulin glands but these traits may vary according to environmental influences. The objective of this research was...
The scale dependence of velocity variances is studied using data collected from a grassland site, a heather site, and four forested sites. The dependence of velocity variances on averaging time, used to define the fluctuation quantities, is modeled. The crosswind velocity variance is emphasized, because it is more difficult to...
Length of survival of the monogenetic trematode Gyrodactylus stellatus in serum and mucus collected from English soles Pleuronectes vetulus at different stages of a laboratory epizootic suggests that both the mucus and serum may be involved in resistance to the parasite. In general, trematode survival was shorter in the serum...
Published April 1991. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Photosynthetic diatoms and marine bacteria contribute about one third of the net primary production in marine environments. Understanding the interactions between these two organisms is potentially important to the over all flow of carbon in the marine ecosystem.
Crown gall can develop on grapevines wounded by freezing temperatures, mechanical damage or grafting. Increased demand for grape varieties grafted to phylloxera resistant rootstocks has led to increased incidence of crown gall at graft unions. Therefore a search for plant material that is resistant to crown gall has been undertaken....
Crown gall can develop on grapevines wounded by freezing temperatures, mechanical damage or grafting. Pathogenic agrobacteria residing within the vascular system are able to initiate tumor growth in damaged plant cells. Sampling from 21 sites in Oregon vineyards and nurseries yielded diverse populations of pathogenic agrobacteria. Most of the pathogenic...
Published January 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published September 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published September 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Between 1999 and 2009, autonomous hydrophones were deployed to monitor seismic activity from 16° N to 50° N along the Mid-Atlantic Ridge. These data were examined for airgun sounds produced during offshore surveys for oil and gas deposits, as well as the 20 Hz pulse sounds from fin whales, which may...
Published October 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published September 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published April 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published October 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Agrobacterium vitis is a bacterium that causes crown gall in grapevines. Plant injury from freezing temperatures or mechanical damage during cultivation often provide wounds required for infection to occur. Crown gall may kill grapevines and a new shoot is often brought up from the root to replace dead vines. Discovery...
In the study of nutritional variability in potato it is desirable to know the present range of expression and genetic potential for increase. Potato breeding lines and varieties in two separate trials were evaluated for potassium and phosphorus content by wet ashing and Inductively Coupled Argon Plasma Emission Spectrophotometer analysis....
The potential of the developing zebrafish model for toxicology and drug discovery is limited by inefficient approaches to manipulating and chemically exposing zebrafish embryos—namely, manual placement of embryos into 96- or 384-well plates and exposure of embryos while still in the chorion, a barrier of poorly characterized permeability enclosing the...
In this watershed assessment, the authors of the report summarized current conditions and data gaps within the Necanicum River watershed to help to identify how current and past resource management is impacting aquatic resources.
Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Sulfur and copper are important for human health.
Sulfur deficiency is rare, but may occur in the elderly. However,
a large percentage of the U.S. population is deficient in
copper. The purpose of this study was to determine the range
of values for sulfur and copper available in advanced potato...
Calcium and magnesium are two minerals that play prominent roles in animal and plant metabolism. The purpose of this study was to determine if genetic variation exists among advanced potato breeding clones for tuber calcium and magnesium content and the extent of genotype x environment interactions on these two traits....
The temperature and salt dependencies of absorption by liquid water (H₂O) and heavy water (D₂O) were
determined using a hyperspectral absorption and attenuation meter (WET Labs, AC-S). Sodium chloride
(NaCl) was used as a proxy for seawater salts. There was no significant temperature (ψₜ) or salt (ψₛ)
dependency of absorption...
Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The Gibraltar Experiment is a many faceted study of the dynamics
and kinematics of the exchange between the Atlantic and Mediterranean
through the Strait of Gibraltar (Bryden and Kinder, 1986). Net
evaporation over the Mediterranean basin forces a surface inflow of
Atlantic water and a nearly compensating deep outflow of...
Fisheries bycatch threatens populations of marine megafauna such as marine mammals, turtles, seabirds, sharks and rays, but fisheries impacts on non-target populations are often difficult to assess due to factors such as data limitation, poorly defined management objectives and lack of quantitative bycatch reduction targets. Limit reference points can be...
The conceptual framework of an erosion model has been designed to link processes of mass wasting, surface erosion, and channel storage and transport. A program to stimulate mass wasting will be based on a variation of the factor of safety approach which balances forces tending to drive mass movement against...
Recommendations are provided in this watershed analysis to identify actions and management decisions on the part of BLM that might improve watershed health in the Trask River watershed.
In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now...
Integrated Ocean Drilling Program (IODP) Expedition 316 Sites C0006 and C0007 examined the
deformation front of the Nankai accretionary prism offshore the Kii Peninsula, Japan. In the drilling area,
the frontal thrust shows unusual behavior as compared to other regions of the Nankai Trough. Drilling
results, integrated with observations from...
A central goal of green chemistry is to avoid hazard in the design of new chemicals. This objective is best achieved when information about a chemical's potential hazardous effects is obtained as early in the design process as feasible. Endocrine disruption is a type of hazard that to date has...
BACKGROUND: Plant phenotype datasets include many different types of data, formats, and terms from specialized vocabularies. Because these datasets were designed for different audiences, they frequently contain language and details tailored to investigators with different research objectives and backgrounds. Although phenotype comparisons across datasets have long been possible on a...
The carbon system of the western Arctic Ocean is undergoing a rapid transition as sea ice extent and thickness decline. These processes are dynamically forcing the region, with unknown consequences for CO2 fluxes and carbonate mineral saturation states, particularly in the coastal regions where sensitive ecosystems are already under threat...
Abstract: The ChemCam instrument, which provides insight into martian soil chemistry at the submillimeter scale, identified two principal soil types along the Curiosity rover traverse: a fine-grained mafic type and a locally derived, coarse-grained felsic type. The mafic soil component is representative of widespread martian soils and is similar in...
Mars Pathfinder successfully landed at Ares Vallis on July 4, 1997, deployed and navigated
a small rover about l00 m clockwise around the lander, and collected data from three science
instruments and ten technology experiments. The mission operated for three months and returned
2.3 Gbits of data, including over 16,500...