Pastures consisting of mixtures of subclover (Trifolium
subterraneum) and grasses have responded to sulfur fertilization
on many sites in Douglas County, Oregon. The objectives of this
study were to examine specific changes in forage quality which occur
as sulfur is applied in excess of the amount required for maximum
yield...
In order to determine how contaminants from pharmaceutical, agriculture, and industry will move through groundwater systems, it is imperative to further our understanding of the relationship between physical, biological, and chemical properties of aquifers and transport and transformation of these products. Several studies have explored how heterogeneities in groundwater systems...
The uptake of methylammonium (MA) by Chesapeake Bay phytoplankton was measured in short term experiments by using the 14C radioisotope. This uptake was inversely related to ambient NH4+ concentrations, and the specificity for uptake of both substrates was demonstrated by competitive inhibition. At stations with low ambient NH4+, MA uptake...
Using 15N-labeled NH4+, we assessed the time-course of NH4+ uptake, the parameters of saturation kinetics, and the rates of incorporation of NH4+ into trichloroacetic acid-insoluble material by Chesapeake Bay phytoplankton. The amount of NH4+ taken up by the phytoplankton increased linearly with time for 2 h for all samples growing...
Marine sponges are vital components of benthic and coral reef ecosystems, providing
shelter and nutrition for many organisms. In addition, sponges act as an essential carbon
and nutrient link between the pelagic and benthic environment by filtering large quantities
of seawater. Many sponge species harbor a diverse microbial community (including...
Marine sponges are vital components of benthic and coral reef ecosystems, providing
shelter and nutrition for many organisms. In addition, sponges act as an essential carbon
and nutrient link between the pelagic and benthic environment by filtering large quantities
of seawater. Many sponge species harbor a diverse microbial community (including...
Full Text:
, M. L., Blake, E., Mulheron, R., McCarthy, P. J., Blackwelder, P., Thurber,
R. L. V., & Lopez, J. V
Marine sponges are vital components of benthic and coral reef ecosystems, providing shelter and nutrition for many organisms. In addition, sponges act as an essential carbon and nutrient link between the pelagic and benthic environment by filtering large quantities of seawater. Many sponge species harbor a diverse microbial community (including...
A systematic investigation was made of the distribution of short wave radiation within the crown of an open-grown Douglas-fir tree. The study tree was 23 years old, 14 meters tall and had a maximum crown diameter of about ten meters. Global radiation was measured every 15 cm along eight different...
Tbc expanding complexity of database application worlds, and the accelerating pace of change of these worlds mandate data models which support some of the tasks of data interpretation which formerly were borne by the applications programs. Chief among these are the support for virtual data, definition of transactions, and enforcement...