A study was made to clarify the relationships of Mentzelia mollis
Peck and two poorly understood taxa of Mentzelia (Loasaceae) to the
other members of the genus, its sections, and its subsections, and
to describe the general ecology of each taxon.
Within the genus, the section Trachyphytum is characterized by...
The goal of the study was to collect data on the ecology and
reproduction of Sophora leachiana in order to help explain the rarity
and restricted range of this species. There are 13 known populations
of S. leachiana, occurring in a 29 by 6.4 km area in the Siskiyou
Mountains...
These essays are an attempt to rebuild memories that explore the nature of work and family. They explore how work knocks against the joints of the body and against the joints between family members, and, as time passes, how the next generation inherits the family line of work only to...
The impact of recent severe droughts throughout the United States, the potential for climate change to intensify the frequency and severity of drought, and discussion about the future of government assistance in agriculture highlight the need for a transition from drought as ‘disaster’ to drought as ‘managed risk’. However, guidance...
Full Text:
Dannele E. Peck for the degree of
Doctor of Philosophy in
Agricultural and Resource Economics
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...
Double-crested cormorants (Phalacrocorax auritus) and Brandt’s cormorants (P. penicillatus) nest sympatrically in a large mixed-species colony on East Sand Island (ESI) in the Columbia River estuary. Ecological theory predicts that such morphologically similar species will partition prey resources when faced with resource limitations. During the summer of 2014, I investigated...
In 1976 the Oregon legislature defeated a bill to assume
primary enforcement responsibility (primacy) of Oregon drinking water
supply systems under the purview of the Safe Drinking Water Act (PL 93-
523), and subsequently reduced state drinking water supervision program
funding by 90%. Since that time Oregon drinking water systems...
A qualitative evaluation was made of the adherence between
borosilicate glass and the ceramics, steatite and alumina. Three
basic adherence studies were performed.
(1) A comparison between the x-ray diffraction patterns of
the ceramic and the fused glass-ceramic powder mixture was made
to determine if any new compounds were formed...