A Monitoring Strategy for Application to Salmon-Bearing Watersheds
Monitoring of stream system health is the systematic collection of data on environmental parameters that are linked to beneficial uses and known to be sensitive to land management activities and natural events. Monitoring is used to investigate relationships, validate assumptions and models, assess current condition and follow trends, and improve the basis for management of resources. Such monitoring may involve collecting data within the stream or on the landscape. In-stream monitoring may involve measurement of the physical or chemical characteristics of the channel or water or may be focused on biological responses of fish and other aquatic or riparian-dependent species. Impacts to the stream system occur by direct actions taken in channels or from the indirect effects of activities occurring in riparian areas, floodplains, hillslopes, or on the entire watershed. These effects can be focused at the scale of a single reach or can be more widespread. The spatial distribution of activities and effects requires that monitoring be conducted with respect to this spatial context and also stratified according to representative components of the landscape and stream system. Also, the spatial distribution and temporal characteristics of environmental variables create “habitat” for aquatic biologic communities at a variety of scales that monitoring and data analysis must elucidate. In fact, land management activities vary in type (forestry, range, mining, agriculture, municipal) but their effects on streams can be evaluated in common terms of sediment, water temperature, channel and bank structure, woody debris, pool frequency and depth, biotic community properties, etc.). Effects of land management activities on a stream may be monitored from single sources close to the activity. And because multiple activities are distributed across a watershed in complex overlapping ways and the degradation and recovery responses are often lagged, their effects on the stream and biota may be both cumulative and out of phase with current levels of activities, thereby making it difficult to attribute all current actions with current condition.
McCullough, D.A. and F.A. Espinosa Jr. 1996. A Monitoring Strategy for Application to Salmon-Bearing Watersheds. Columbia River Inter-Tribal Fish Commission Report reference #96-05, Portland, Oregon.