. Programme d'évaluation des tendances critiques rapport de 2002. Projet d'évaluation des tendances critiques ; la gestion des écosystèmes ; la surveillance de l'environnement ; les ressources naturelles des sondages. HablUt 30,0 35,0 Sam Figure 3. Rang-centile des scores de l'habitat multi-métriques Conclusion Le score de l'habitat fournit un excellent indicateur de la qualité de l'eau pour compléter les divers indicateurs biologiques et le score biologique métriques. C'est significativement corrélé à ces mesures biologiques (coefficient de corrélation de-.5). Plusieurs des mesures de l'habitat des cours qu'il contient peuvent être directement améliorée par la gestion, r

• Contributeur: The Book Worm / Alamy Banque D'Images
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. Critical trends assessment Program 2002 report. Critical Trends Assessment Project; Ecosystem management; Environmental monitoring; Natural resources surveys. 30.0 35.0 HablUt Sam Figure 3. Percentile rank of habitat scores Conclusion The multi-metric habitat score provides an excellent indicator of stream quality to supplement the various biological indicators and the multi-metric biological score. It is significantly correlated to these biological measures (correlation coefficient of-.5). Several of the stream habitat measures that it includes can be directly improved through management, restoration, or pollution control activities. The amount of canopy cover can be affected, the natural channel may be restored, nearby activities that affect stream odor and appearance (and turbidity) may be reduced or buffered, land uses can be changed. Such changes should improve overall stream quality and be reflected in both the habitat and biological scores. Additional habitat characteristics will be added to the multi-metric habitat score in the future. Once the issues related to properly measuring algal growth are resolved, this factor could be included. RiverWatch procedures were recently revised to include a new measure of siltation to replace the embeddedness procedure, which was not consistently implemented. Siltation could replace silt substrate in the index, leaving a single substrate measure in the index. Turbidity may be added as well in the future, although it seems that other measures capture the effects of turbidity. The habitat score would be a more powerful indicator if it were to incorporate additional physical characteristics of streams that are amenable to management and restoration. For example, channel sinuosity, width of the riparian vegetation zone, and stream bank cover or stability all are known to affect the quality of stream habitat. Volunteers could be trained to reliably measure each of these characteristics. Scores on the two multi-metric indices

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