A 0.05 km2 patterned bog and a 0.29 km2 ribbed fen were compared to determine the influence of their morphometry on runoff and evapotranspiration. The bog hydrology was dominated by irregularly located and poorly linked pools ≤1.0 m deep, separated by prominent ridges containing local water-table maxima. This small basin had an appreciable lag-to-peak time (e.g. 6 h), and a low runoff ratio (0.1 to 0.2), because of the large depression storage of the pools, and a long detention storage caused by the weak pool-to-pool linkage. The ribbed fen was dominated by a 1.3 km water track, which consisted of shallow pools (≤0.25 m deep), separated by low ridges that did not produce local water table maxima. The pools were well linked, but their sequential arrangement resulted in a very large detention storage which trimmed the runoff ratio to only 0.003 to 0.07. The lag-to-peak time was relatively short (approx. 3 h), because of sheet flow in the lower water track, just above the weir. The large depression and detention storage of both systems enhanced evapotranspiration losses. Between July 5 and August 14, 1990, evapotranspiration from the bog was 97 mm, compared to 126 mm from the fen, while runoff was only 12 and 28 mm for the bog and fen, respectively. Evapotranspiration from ridges was 67 and 84% of pool evaporation, in the bog and fen respectively.

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Streams and riparian areas in the Bowron River watershed were assessed using the riparian management routine effectiveness evaluation, a protocol developed for postharvest operational monitoring in British Columbia. Located in the British Columbia interior, the study watershed has had several decades to recover since a period of intensive salvage logging from 1977 to 1987 in response to a spruce beetle (Dendroctonus rufipennis) outbreak. Correlations were found with site-specific watershed characteristics and attributes that are used to answer the protocol indicator questions. Channel width was the strongest covariate, exhibiting the most significant relationships with the stream and riparian attributes. Suggestions on how to adjust standard protocols for stream size and landscape heterogeneity are discussed and include the use of appropriate reference sites for baseline data. We used correlations with watershed characteristics and multiple regressions based on regional reference sites to predict upper and lower threshold values by which attribute measurements could be compared. Sites that were assessed above or below threshold values for an attribute were considered to be outside the range of natural variation and were given a failing score. Attributes with the most failures 20-30 years postharvest were disturbed ground, bare soil, undercut banks, and shade. Résumé :Les cours d'eau et les zones riveraines du bassin hydrographique de la rivière Bowron ont été évalués en appliquant l'évaluation de routine de l'efficacité de la gestion riveraine, un protocole développé pour le suivi opérationnel postrécolte en Colombie-Britannique. Situé à l'intérieur des terres, en Colombie-Britannique, le bassin hydrographique à l'étude a pu récupérer pendant plusieurs décennies depuis la période de coupe de récupération intensive de 1977 à 1987 en réaction à une épidémie du dendroctone de l'épinette. Des corrélations ont été observées entre des caractéristiques du bassin hydrographique propres au site et des attributs utilisés pour répondre aux questions indicatrices du protocole. La largeur du chenal était la covariable la plus significative; elle était la plus significativement reliée aux attributs du cours d'eau et de la zone riveraine. Les auteurs présentent des suggestions pour ajuster les protocoles standard selon la largeur des cours d'eau et l'hétérogénéité du paysage incluant l'utilisation de sites de référence appropriés pour avoir des données de base. Nous avons utilisé les corrélations avec les caractéristiques du bassin hydrographique et des régressions multiples basées sur des sites régionaux de référence pour prédire des valeurs limites supérieure et inférieure auxquelles les mesures des attributs pouvaient être comparées. Les sites pour lesquels la valeur d'un attribut était inférieure ou supérieure aux valeurs limites étaient considérés comme étant à l'extérieur de l'étendue de la variation naturelle et ont reçu une mention d'échec. Les attributs qui ont reçu le plus de mentions d'échec 20 à 30 ans après la coup...

Stream evaluation field data from 44 basins in the Bowron River watershed were used in combination with results from GIS spatial analysis to investigate whether impacts from logging the riparian zone of upperbasin streams could be detected at downstream sites. The field data included responses to stream indicator questions taken from the BC Ministry of Forests and Range's Riparian Management Routine Effectiveness Evaluation (RMREE). The evaluation included questions associated with the following stream indicators: (1) channel bed condition, (2) channel bank condition, (3) in-stream large woody debris processes, (4) channel morphology, (5) aquatic connectivity, (6) fish cover, (7) moss, (8) fine sediment, and (9) aquatic invertebrates. This study examined the negative responses to these indicator questions in relation to the amount of upstream riparian harvesting that took place in each basin. Evaluated reaches that had been harvested to the stream bank were not significantly different from sample reaches with streamside buffers when both groups had harvested upstream riparian areas. Negative responses increased significantly at 30% upstream riparian harvest. Sites were grouped by this threshold (low/high) and compared to nonharvested sites to examine negative responses for each indicator. In discussing the results, we explore the potential role of recovery of harvested drainages, negative responses in the non-harvested group, elevation, soil erodibility, in-stream large woody debris processes, and aquatic invertebrate diversity (which may subsequently impact food and habitat supply for fish). The results support the best management practice of leaving a "no-harvest" riparian reserve on all small streams in order to mitigate downstream impacts.