Field observations are made of the formation of backwash ripples
on the beachface, formed by undular hydraulic jumps generated by backwash
down the beach face colliding with wave bores. Measured ripple
wavelengths range from set averages of 48 to 70 cm. Within a particular
set of ripples there is a...
I tested the hypothesis that there is a correlation between inundation period and net primary production (NPP) in estuarine salt marshes through an observational experiment at South Slough National Estuarine Reserve, Oregon. I estimated primary production and inundation period for selected monotypic plant communities in (1) a naturally restored wetland...
A field experiment designed to test the hypothesis that infragravity and lower frequency waves influence the patterns of erosion and deposition on the beach foreshore has been carried out. The data show coherent fluctuations in the foreshore sediment level which can be related to low frequency wave motions. The fluctuations...
Rare plant reintroductions that result in additional or more viable wild populations are important conservation tools for maintaining biodiverse ecosystems. Ideally, such projects are best designed as experiments, to improve biological and ecological knowledge of the selected species and monitoring long-term results. Northern wormwood (Artemisia campestris var. wormskioldii: Asteraceae), a...
Kesterson Reservoir (Kesterson) received subsurface agricultural drainwater containing high levels of salts and other minerals from farmland in the San Joaquin Valley of California. Aquatic plants and invertebrates were sampled at Kesterson in May, August, and December of 1984. The reservoir supported a different biota and lower species diversity than...
Quantification of contemporary sediment and carbon accumulation within Oregon tidal saline wetlands will: (1) fill a critical knowledge gap, and (2) naturally test without complicating variables whether sea level rise or sediment supply primarily control wetland growth. Here we measure vertical accretion rates and carbon burial rates in three Oregon...
Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I radio-marked 72 female mallards in the Willamette Valley of Oregon in March-April 1995-96 to document wetland habitat selection during pre-nesting...
The hypothesis that inoculation of transplants with vesicular-arbuscular mycorrhizal (VAM) fungi before planting into saline soils would alleviate salt effects on growth and productivity was tested on lettuce (Lactuca sativa L.) and onion (Allium cepa L.). A secondary hypothesis was that the fungi isolated from a saline soil would be...
Quantification and comparison of morphological changes over the last ~300 y in Oregon salt marshes provide valuable insights into the tectonic, hydroclimatic, and anthropogenic processes shaping this important intertidal zone. Understanding of the rates and drivers of salt marsh change contextualizes intertidal habitats within the sediment routing system (i.e., source...