Mechanical thinning and prescribed fire are widely used to restore western forests after a century of fire suppression, yet we know little about
how these treatments affect understory communities where plant diversity is highest. We followed understory plants and environmental factors in
old-growth, Sierran mixed conifer for two pre-treatment and...
In order to understand what controls the composition of suspended particulate material (SPM) in estuarine turbidity maxima (ETM), a set of SPM samples collected in the Columbia River and estuary (northwestern USA) during 3 seasons (fall 1990, summer 1991, spring 1992) was analyzed for detrital mineral (Min), total organic matter...
In Sierra Nevada forests, shrubs are considered strong soil moisture competitors with regenerating trees, reducing seedling establishment, and
slowing growth. Recent studies, however, suggest that in some circumstances shrubs can facilitate tree establishment and growth by modifying
harsh microclimate conditions; increasing acquisition of water, carbon, and/or nutrients via shared mycorrhizal...
Nitrogen is a limiting resource in many temperate forests and nitrogen-fixing plants are usually limited to the early
stages of post-disturbance succession. In fire-dependent Sierra Nevada forests, however, Ceanothus cordulatus is
relatively abundant even in old-growth forest conditions which are at least partly maintained by fire.We conducted
a field experiment...
In Sierra Nevada forests, shrubs are considered strong soil moisture competitors with regenerating trees, reducing seedling establishment, and
slowing growth. Recent studies, however, suggest that in some circumstances shrubs can facilitate tree establishment and growth by modifying
harsh microclimate conditions; increasing acquisition of water, carbon, and/or nutrients via shared mycorrhizal...
Nitrogen is a limiting resource in many temperate forests and nitrogen-fixing plants are usually limited to the early stages of post-disturbance succession. In fire-dependent Sierra Nevada forests, however, Ceanothus cordulatus is relatively abundant even in old-growth forest conditions which are at least partly maintained by fire. We conducted a field...
Storage lipids of fifth copepodites (C5) of Culanus finmarchicus from Georges Bank and the Gulf of Maine were quantified from video images and by Iatroscan (thin-layer chromatography with flame-ionization detection, FID). Oil withdrawn from the oil sac by micropipette was pure wax ester (WE); triacylglycerols (TAG) were elsewhere in the...
The vitamin D receptor (VDR) mediates the pleiotropic biologic effects of 1alpha,25
dihydroxy-vitamin D3. Recent in vitro studies suggested that curcumin and poly-unsaturated fatty
acids (PUFAs) also bind to VDR with low affinity. As potential ligands for the VDR, we hypothesized
that curcumin and PUFAs would induce expression of known...
Prescribed fire can release herbaceous forages from woody plant competition thus promoting increased forage plant production, vigor, and accessibility. Prescribe fire also consumes standing litter thereby improving forage quality and palatability. Consequently, prescribed fire is commonly considered an effective tool for manipulating livestock distribution on rangelands. Efficacy of this tool...
Prescribed fire is commonly applied world-wide as a tool for enhancing habitats and altering resource-selection patterns of grazing animals. A scientific basis for this practice has been established in some ecosystems but its efficacy has not been rigorously evaluated on mesic sagebrush steppe. Beginning in 2003, resource-selection patterns of beef...
Plant wax lipids and lignin phenols are the two most common classes of molecular markers that are used to trace vascular plant-derived OM in the marine environment. However, their ¹³C and ¹⁴C compositions have not been directly compared, which can be used to constrain the flux and attenuation of terrestrial...
Marine sediments around volcanic islands contain an archive of volcaniclastic deposits, which can be used to reconstruct the volcanic history of an area. Such records hold many advantages over often incomplete terrestrial data sets. This includes the potential for precise and continuous dating of intervening sediment packages, which allow a...
Measurements of the U₃₇ K’ index and the absolute abundance of alkenones in marine sediments are increasingly used in paleoceanographic research as proxies of past sea surface
temperature and haptophyte (mainly coccolith-bearing species) primary productivity, respectively. An
important aspect of these studies is to be able to compare reliably data...