Forest Image

Type N Monitoring

Stream temperature within the Type N stream and in downstream fish-bearing waters

Temperature dataloggers (Onset StowAway TidbiTs) are used to monitor water, soil, and air temperature at a minimum of four stations within each of the Type N basins. Stations range from the fish-bearing waters boundary (Type N/F junction) to the uppermost point of perennial flow. The middle stations are located relative to the buffer in the basins receiving the current Forests and Fish buffer treatment and in comparable locations in basins receiving the other buffer treatments. Additional water stations are located at the downstream end of tributaries and 100 meters downstream of the Type N/F junction.

Hemispherical canopy photos are taken every year at ten points within each of the Type N basins. The photos are analyzed using Hemiview software to determine the amount of solar radiation and shade at each photo point.

Stream flow, suspended sediment, and nutrient export from Type N streams

The Turbidity Threshold Sampling (TTS) methodology (Lewis 1996) is being used in eight of the 18 study basins to measure stream flow and suspended sediment and nutrient export. The TTS methodology includes a flume or in-situ flow meter, a depth pressure transducer, a turbidity sensor, and a pump sampler at the Type N/F junction. A datalogger records the stage and turbidity data and is programmed to collect water samples at pre-set stage and turbidity thresholds. The water samples are analyzed at the lab for suspended sediment concentration (SSC), total non-volatile suspended solids (TNVSS), nitrite-nitrate (NO2NO3), total persulfate nitrogen (TPN), and total phosphorus (TP). Additional grab samples are collected from the stream basins every six weeks and are analyzed for SSC, TNVSS, ammonia, NO2NO3, TPN, orthophosphate, TP, and total organic carbon.

Organic matter input to and export from Type N streams and macroinvertebrate export from Type N streams

Paired litterfall traps are deployed at four stations within the eight study basins assessed for flow. Stations range from the fish-bearing waters boundary (Type N/F junction) to the uppermost point of perennial flow. The middle stations are located relative to the buffer in the basins receiving the current Forests and Fish buffer treatment and in comparable locations in basins receiving the other buffer treatments. Litterfall trap contents are collected every six weeks, sorted into coniferous, deciduous, wood, and miscellaneous categories, dried, ashed, and weighed.

Drift nets are deployed every six weeks in the eight study basins assessed for flow. The nets are attached to the downstream end of the flume or near the in-situ flow meter. Detritus is sorted into coniferous, deciduous, wood, and miscellaneous categories, dried, ashed, and weighed. Macroinvertebrates are identified and measured, and regression models are used to estimate biomass.