| Successful freshwater management efforts require (1) optimizing water quality monitoring and assessment tools to ensure their accuracy, efficiency, and applicability, and (2) developing adequate mechanisms to foster stakeholder involvement in water resource decision-making. This is especially true for urbanized areas, where human activity shapes the landscape in a multitude of ways across a variety of scales, necessitating a better understanding of linkages between terrestrial and aquatic environments on the part of researchers, decision-makers, and the general public. To determine whether qualitative habitat evaluation methods capture physical features of importance to biological communities, I examined the relationship between a widely used local-scale, observer-based physical habitat assessment and the aquatic macroinvertebrate community at 84 sites on 14 streams running an urban-rural gradient in the San Jose, California metropolitan area. I found that while certain aspects of physical habitat (e.g., channel flow status, riffle frequency, and riparian zone width) were related to biological condition, there was still a great deal of unexplained variation in the macroinvertebrate data, indicating the influence of other, possibly larger scale, variables. Landscape pattern metrics provide the potential to quantify the effects of large-scale human impacts on freshwater ecosystems, but have not been extensively tested, particularly in a watershed context. In the same study area, I quantified landscape pattern using metrics of spatial configuration calculated in site-specific subdrainage areas. After reducing the landscape metrics using multivariate factor analysis, I examined the relationship between aquatic macro invertebrate communities and landscape pattern. I found that landscape pattern metrics, including patch density and contagion, did explain a good deal of variation in the biological community, although the relative importance of specific metrics varied across catchments. This is reflective of the importance of not only the number, density, and distribution of land use/land cover types, but also the shape and intermixing of patches. The application of advanced technology to freshwater management efforts also has implications for enhancing community involvement. Although not yet extensively applied in natural resource management, Internet-based Geographic Information Systems (webGIS) technologies could facilitate public involvement in freshwater monitoring and assessment efforts by allowing users to access data using any web browser at virtually any time. |
