The objective of this study was to determine if the stability of water temperature attributes suggested by an analysis conducted in 2003 (Larson and Larson 2001; 2003) was continued over a 20-yr period. The pattern of degree accumulations observed in the daily heating and cooling cycles of three streams in 1998, 2013, 2014, 2016, and 2018 were studied in Grant County, Oregon. The average air and water temperatures remained stable at each site and followed the expected natural patterns (Larson and Larson 2001) described in an earlier study. Within each sampling year, mean air and water temperature remained within 1-2 degrees C and there were no significant differences between the rates of heating between the study years or between sites. (C) 2020 The Society for Range Management. Published by Elsevier Inc. All rights reserved.

A 2-yr study of livestock/wildlife tracking was conducted on four streams in eastern Oregon. Binomial sampling of tracks proved to be an effective statistical method for monitoring the proportion of samples containing tracks on stream greenlines and testing the observed value against an established standard. Study results indicate that tracks are related to variables outside of the control of livestock grazing management.

•Browse estimates in this study were made using a random sampling strategy to monitor riparian shrub communities using presence or absence to determine the percent of shrub occupancy and intensity of browsing.•This height-based shrub monitoring takes the guesswork out of complex browse estimates.•The strategic timing of monitoring periods facilitates separation of wildlife and livestock browsing impacts.•Height-based shrub monitoring was an efficient and repeatable method for tracking shrub occupancy, maturity, and shrub form.

The viability of the agriculture industry depends on the private landowner having a working knowledge of watershed functions in order to make environmental management a part of their operational plans. A three-year study was designed to capture the temperature signature and substrate sediments of individual stream segments. The daily pattern of temperature change (4 hr. periods between 5 am and 5 pm) in both air and water were examined based on elevation and were classified as cold, cool, and warm stream segments. Thermal gradients and heating rates at the study sites were different when compared by elevation. Data compared across elevation showed cold water sites had the greatest temperature changes occurring between 1 and 5 pm and cool and warm water sites changed most between 9 am and 1 pm. Adiabatic stratification of the watershed environment has an influence on the thermal pattern of stream temperature and should be considered when assessing daily maximum water temperatures. Channel substrate measurement of "fines" was between 0.03% and 4% in 2000 and no substrate sediments were found in quantities greater than 20%. Overall, thermal and sediment pollution were undetected once natural and/or background conditions were established.

Reply by S.L. Larson, L.L. Larson, and P.A. Larson, p. 100-101.

Airborne infrared thermal radiography has been proposed as a tool which may be used to monitor the water temperature along the network of streams and rivers which compose a watershed. The proponents of this method correlate vegetative shadows on a stream channel with reduced infrared radiation (IR) reception in the radiographic data to suggest that the water temperature is reduced in such areas. Two methods are employed to demonstrate that this interpretation of the data is in error. First, the fundamental principles of thermodynamics are employed to show that if the stream is in fact flowing, the water affected by any cooling process cannot remain in the vicinity where it was cooled. Second, temperature data taken from a stream channel are used to show that the water flowing in the channel is essentially unaffected by the patterns of vegetative shade on the surface of the channel.

Field studies were undertaken to study the influence of thermal gradients on rates of stream heating and cooling. Results from the study on four watershed suggest that the rates of stream heating and cooling are strongly influenced by exposure to the surrounding thermal environment. Air temperature, when used as an index of the thermal environment, provided a mechanism for estimating the rate of stream heating or cooling in different thermal environments. Rates were tested for significant difference and summarized to provide a framework for anticipating rates of heating and cooling given thermal environment renditions. Monitoring water temperature for watershed assessments determines how much thermal pollution is in a stream. Collecting temperature data between two established monitoring sites, and wing air or soil temperatures as an indicator of the watershed's thermal response to climatic factors ran help describe why, as well as where, the pollution is occurring This study evaluates a means of quantifying and evaluating rates of water heating through the application of scientific principles.