For the first time, a collaborative study [http://iopscience.iop.org/1748-9326/8/1/014039] has compared water quality trends in forested streams across the country that are largely undisturbed by land use or land cover changes. The study draws on 559 years of stream nitrate and 523 years of stream ammonium data from 22 streams in 7 experimental forests across the country. The study found that even near-pristine forested streams are subject to change.
The Kings River Experimental Watersheds hosts the Southern Sierra Critical Zone Observatory--a National Science Foundation effort to gain a better understanding of the zone of earth where "rock meets life." The critical zone extends from the tops of the trees to the groundwater and covers the entire earth where there is land. Download the video created by a UA Flandrau Science Center team to introduce the motivation and science involved in the National Critical Zone Observatory research program.
Kings River Experimental Watersheds (KREW)
KREW Location: Teakettle Experimental Forest
Beginning in 1936, three potential experimental watersheds were the subjects of intensive geology and soil studies: Onion Creek (Tahoe National Forest), and Big Creek and Teakettle Creek (Sierra National Forest). In 1938 a 1,300 ha area surrounding Teakettle Creek was designated the Teakettle Experimental Area and five drainages were chosen for study.
Stream-gauging stations and sediment basins were built and hydrology research begun. Research halted during World War II (1942-1956). In 1957 studies were reactivated and regular records of snowfall and water yields were collected again. The area was officially designated The Teakettle Creek Experimental Forest on 16 December 1958 (North et al. 2002).
The objective of the experimental forest was to develop timber harvest patterns that would increase water yield. However, studies completed in the 1950s and 1960s at Yuba Pass and Sagehen Creek suggested moderate forest cover removal had little effect on water yield in the Sierra Nevada. In the 1960s the focus of Teakettle research switched to water flow measurements in relation to weather patterns. This study was continued into the 1980s until the Forest Service stopped the study because of budget constraints and the logistics of maintaining a remote site. The stream discharge records are on the U.S. Geologic Survey web site for the years that USGS ran the site. The more recent data records (paper and digital) exist for the years that the Forest Service ran the site but are not quality-assured for distribution.
To compare the effects of different levels of thinning and burning on mixed-conifer ecosystems, an experiment was initiated in 1998 called the Teakettle Ecosystem Experiment (North et al. 2002). As a precursor to this experiment, an extensive analysis of vegetation condition at Teakettle was made to map and identify different forest communities. The eastern side of Teakettle has 18 4-ha plots for this experiment (three replicates each of understory thin/no burn, overstory thin/no burn, burn only, understory thin/burn, overstory thin/burn, control). Data collection continues on the effect of these treatments (http://teakettle.ucdavis.edu).
Four of the original stream gauging sites remain and were not impacted by the Teakettle Ecosystem Experiment. Since the Teakettle Experimental Forest was started as a hydrologic study, it provides a unique long-term record regarding stream discharge and sediment loads from a headwater, mixed-conifer forest with little disturbance. While this area has had cattle grazing and fire suppression, it has few roads and no history of timber harvesting. All four of the stream gauging sites were evaluated and three were determined to be in good structural condition. The Kings River Experimental Watershed (Hunsaker and Eagan 2003) selected one of these watersheds (TK3) as a control for the Bull Site and renovated the facility in 2003. This watershed began data collection in October 2003 as part of KREW.