Di-nitrogen (N₂) fixation plays a well-recognized role in the enhancement of primary production
and arguably particle export in oligotrophic regions of the subtropical and tropical oceans.
However, recent evidence suggests that N₂ fixation may also be significant in regions of the
surface ocean proximate to or overlying zones of intense...
Concurrent measurements of predator and prey δ¹⁵N isotope values demonstrated that a cross-shelf
isotopic gradient can propagate through a marine food web from forage species to top-tier predators and
indicate foraging areas at a scale of tens of kilometers. We measured δ¹³C and δ¹⁵N in muscle tissues of
thick-billed murres...
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...
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...
A large-eddy simulation study was performed to characterize turbulence in sparse, row-oriented canopies. This was accomplished by simulating a set of heterogeneous row-oriented canopies with varying row vegetation density and spacing. To determine the effects of heterogeneity, results were compared to horizontally homogeneous canopies with an equivalent ‘effective’ leaf area...
In September 1991, the Bureau of Land Management asked the Secretary of the Interior to convene the Endangered Species Committee. The Bureau wanted permission to proceed with 44 timber sales In Oregon that the U.S. Fish and Wildlife Service had ruled would jeopardize the continued existence of the northern spotted...
Abstract— This study describes the sound produced by a
hydrokinetic turbine operating in a riverine environment near
Iguigig, AK (USA). Drifting spar buoys equipped with
hydrophones and GPS loggers were used to characterize
temporal and spatial variability in turbine sound over a range of
turbine operating conditions. Because of the...
The ability to reconstruct past ocean currents is essential for determining ocean circulation’s role in global heat transport and climate change. Our understanding of the relationship between circulation and climate in the past allows us to predict the impact of future climate-driven circulation changes. One proposed tracer of past ocean...
Each year, over 45 countries export 30 million fish from coral reefs as part of the
global marine ornamental aquarium trade. This catch volume is partly influenced
by collection methods that cause mortality. Barotrauma in fish resulting from forced
ascent from depth can contribute to post-collection mortality. However, implementing
decompression...