The current paradigm of plant nutrient limitation during ecosystem development predicts a change from nitrogen (N) limitation when substrates are young to phosphorus (P) limitation when substrates are old. However, there are surprisingly few direct tests of this model. We evaluated this theory experimentally along a three million year semi-arid substrate age gradient using resource additions to...

Soil microorganisms drive critical functions in plant-soil systems. As such, various microbial properties have been proposed as indicators of soil functioning, making them potentially useful in evaluating the recovery of polluted soils via phytoremediation strategies. To evaluate microbial responses to metal phytoextraction using hyperaccumulators, a microcosm experiment was carried out to stud...

Diamondback terrapins (Malaclemys terrapin) inhabit estuaries in eastern USA and may tolerate salinity of sea-water for short durations. Many North American estuaries are adversely affected by anthropogenic impacts, such as pollution, dredging and invasion by non-native plants. Many nesting areas have been altered or destroyed, causing terrapins to nest on roadsides and artificial islands made ...

Methanol is an abundant atmospheric volatile organic compound that is released from both living and decaying plant material. In forest and other aerated soils, methanol can be consumed by methanol-utilizing microorganisms that constitute a known terrestrial sink. However, the environmental factors that drive the biodiversity of such methanol-utilizers have been hardly resolved. Soil-derived iso...

Four species of pteromalid parasitoids [Muscidifurax raptor Girault & Sanders, Spalangia cameroniPerkins, Spalangia endiusWalker, Spalangia geminaBoucek, and the chalcididDirhinus himalayanus (Masi)] were evaluated for their ability to locate house ßy pupae at various depths in poultry manure (41% moisture), ßy rearing medium (43% moisture), and sandy soil (4% moisture) from a dairy farm. Searc...

Animal social signals are important for population recognition, communication, and mate choice. Although natural selection often favours cryptic coloration, sexual selection can underlie patterns of coloration that function in interor intrasexual communication. We compared social signal coloration of three lizard species across a substrate colour ecotone in New Mexico. These species exhibit cry...

Soil respiration (Rs) is a combination of autotrophic and heterotrophic respiration, but it is oftenmodeled as a single efflux process, influenced by environmental variables similarly across all time scales. Continued progress in understanding sources of variation in soil CO2 efflux will require development of Rs models that incorporate environmental influences at multiple time scales. Coherenc...

This paper compares five commercially available DNA extraction methods with respect to DNA extraction efficiency of Salmonella enterica serovar Enteritidis from soil, manure, and compost and uses an Escherichia coli strain harboring a plasmid expressing green fluorescent protein as a general internal procedural control. Inclusion of this general internal procedural control permitted more accura...

Stability of a soil property to perturbation comprises both resistance and resilience. Resistance is defined as the ability of the soil to withstand the immediate effects of perturbation, and resilience the ability of the soil to recover from perturbation. Functional stability is used here to describe the stability of a biological function to perturbation, rather than the stability of physical ...

In contrast to other transgenic Bacillus thuringiensis (Bt) crops (e.g. Bt maize and cotton), risk assessments of Bt rice on soil ecosystem are few. To assess the influence of Bt rice on rhizosphere soil ecosystems, soil samples from Bt, non-Bt and controls were taken at seedling, tillering, booting, heading and maturing stages. The activities of dehydrogenases, invertase, phenol oxidases, acid...