In a study of cumulative effects of riparian disturbance by grazing on the trophic structure of high desert trout streams, watersheds with greater riparian canopy had higher standing crops of rainbow trout Oncorhynchus mykiss, lower daily maximum temperatures (range, 16-23°C compared with 26-31°C), and perennial flow. Watershed aspect influenced the...
Runup kinematics on a gently sloping natural beach are examined with detailed measurements from video images, resistance wires deployed at five elevations (between 5 and 25 cm) above and parallel to the beach face, and pressure sensors located in the inner surf zone. As suggested in a previous study comparing...
Sandbars are ubiquitous, yet not well understood
beach features that change their position and shape in
response to changing wave conditions. We propose and test
a simple empirical model consisting of two coupled linear
differential equations that represents bar dynamics in terms
of wave forcing and two other state variables:...
Alongshore-separated time series of natural swash motions were obtained over a range of environmental conditions using a video technique. Although the frequency spectra and normalized wavenumber spectra for these motions were particularly bland, wavenumber-frequency spectra of these data showed clear partitions of infragravity band energy levels associated with various wave...
Cartwright and Longuet-Higgins (1956) describe the statistical distribution of maxima that would result from the linear superposition of random, Gaussian waves. The distribution function depends solely upon the relative width of the power spectrum and root-mean-square value of the process time series. Runup field data from three experiments are presented...
Beach response to overwash processes is a topic of significant importance. Two
particular aspects of this topic were chosen for detailed analysis: the distribution of
maximum wave runup elevations and the cross-beach celerity gradient of overwash bores
on natural beaches. Data were collected using both traditional nearshore instrumentation
and recently...
There is currently much national and international interest in measuring commercial fishing capacity. Two quantitative methods that will likely be used for this purpose are data envelopment analysis (DEA) and stochastic frontier (SF) production functions. Although both methods can be used to estimate a production frontier, their underlying assumptions and...
National-scale analyses of fire occurrence are needed to prioritize fire policy and
management activities across the United States. However, the drivers of national-scale
patterns of fire occurrence are not well understood, and how the relative importance of human
or biophysical factors varies across the country is unclear. Our research goal...