Understory

This project brought together a broad range of scientists and engineers to start filling in the many knowledge gaps that exist with respect to the nearshore zone of Lake Tahoe. The nearshore zone in any lake is invariably complex. This zone is where the watershed influences first impact the lake and are therefore present at their full impact or largest concentrations; it is where the water depth is continually varying; it is where the interactions between the sediments of the benthic zone and the water column are greatest; it is where temperature extremes are greatest (warmest water in summer ...

California’s forest practices on non-federal timberlands are regulated by federal, state and local laws, including Forest Practice Rules (FPRs) under the Z’berg-Nejedly Forest Practice Act of 1973. The California Department of Forestry and Fire Protection (CAL FIRE) enforces the FPRs and acts as the lead agency for projects under the California Environmental Quality Act (CEQA). Foresters and timber operators must be licensed, with Licensed Timber Operators (LTOs) required to attend a two-day training session on the FPRs, as well as have adequate experience and insurance. Five different state-s...

Currently, only two-dimensional (2D) linear analytical models can be practically used to predict meander migration of rivers at reach-scale. Such models assume that the ratio of channel width to radius of curvature is much smaller than one. Unfortunately, sharp bends are commonly found in nature and in constructed re-meandered channels. Moreover, linear models assume or compute bed topography with a certain degree of idealization. The hydrodynamic fields obtained with 2D linear and fully non-linear models are compared for a restored, highly meandering reach on Trout Creek in the Tahoe Basin, C...

A macroinvertebrate assessment was conducted on the Caspar Creek Experimental Watershed in northwestern California using a functional feeding group (FFG) classification. The approach, developed over 30 years ago (Cummins 1973), has been tested, modified, and employed in many studies (e.g. Cummins and Klug 1979, Cummins and Wilzbach 1985), Merritt and Cummins 2006). The approach categorizes macroinvertebrates based on their morphological and behavioral mechanisms by which they acquire one or more of six general food types: coarse particulate organic matter (CPOM), fine particulate organic matte...

Lake Tahoe's water clarity has decreased from ~100 feet in the 1970 to ~70 feet in the last few years. Fine inorganic particles are causing about 58% of light attenuation in Secchi disk measurements of water clarity. The 2010 draft of the Total Maximum Daily Load (TMDL) report indicated that the sources of sediment include urban upland loading (i.e., storm water runoff, 72%), non-urban upland loading (9%), atmospheric deposition (both dry and wet, 15%), and stream channel erosion (4%). The project report describes measurements and results collected in the Tahoe Basin that investigate the trans...

The paper by Alila et al. [2009, hereafter referred to as AKSH] presents a technique for analyzing altered peak flow frequencies after logging. The paper suggests that the established method of chronologically pairing peak flows by corresponding hydrologic input at control and treated watersheds is inappropriate, leading to irrelevant research hypotheses and impeding scientific progress. In general, we agree that analyses of changes in flood frequency are useful for evaluating the effects of watershed disturbance, and that simple regression models often provide inadequate descriptions of postt...

Objectives of this exploratory research were: 1) to characterize the contribution of size-specific and total concentrations of organic and inorganic components to the suspended load during high and low flow periods in 4 streams in coastal northern California; and 2) to evaluate relationships between composition and nutritive quality of the suspended loa d with feeding efficiency and condition of salmonid fishes and the abundance of their invertebrate prey. In addition, we conducted laboratory feeding trials to evaluate the effects of suspended sediment concentration, organic: inorganic particl...

The vast majority of small watersheds in Northwest California lack stream gage information. Understanding the high flow behavior of these watersheds is crucial for guiding resource managers in project planning. The purpose of this thesis was to develop a predictive relationship between precipitation and peakflow of streams draining small forested watersheds of the Northern California Coast Range. An antecedent precipitation index approach was developed for this purpose.The five selected watersheds are covered by coastal coniferous forests with drainage areas ranging from 0.4 to 34 km2. Streamf...

The amount of forestry-related water quality monitoring in California has increased significantly in the past ten years. Factors leading to more monitoring include federal and state listing of fish species (i.e., coho salmon, Chinook salmon, steelhead trout) as threatened or endangered, listing of watersheds in northwestern California as sediment impaired under Section 303(d) of the federal Clean Water Act, and new requirements by the State’s Regional Water Quality Control Boards for monitoring of Timber Harvesting Plans (THPs). As a result, several large private timberland owners are now moni...

This RNA occurs along the crest of the southern Siskiyou Mountains in extreme western Siskiyou County. It lies approximately two air miles (3 km) east of the eastern boundary of the Siskiyou Wilderness. Rock Creek Butte (RCB) is a northeast-southwest trending ridge, which is now bisected by the Gasquet-Orleans Road.The RCB RNA has an exceptionally good representation of Brewer spruce on northwest-facing slopes. The Rock Creek Butte Brewer spruce stands are healthy, covering about 138 acres (55.9 ha) and are represented by several age classes ranging from seedlings up to trees 48 in. (122 cm) d...