Forest Investment Account (FIA) - Forest Science Program
FIA Project Y071282

    Using GIS and Multivariate Statistical Analysis to Assess the Relations between Aquatic Habitat Indicators and Forest Harvesting at Both Stream Reach and Watershed Scales
Project lead: Wei, Adam
Author: Wei, Adam
Imprint: Kelowna, BC : University of British Columbia Okanagan, 2007
Subject: Forest Investment Account (FIA), Aquatic habitats, British Columbia
Series: Forest Investment Account (FIA) - Forest Science Program
Using appropriate indicators is an important approach to support sustainable forest and watershed management and has been widely recognized in the scientific and resource management communities. This approach is particularly relevant in BC because of the recent introduction of the results-based Forest and Range Practices Act (FRPA). In spite of significant efforts devoted to selection of forest sustainability indicators, many identified watershed indicators have not been well tested and applied in supporting design of forest management strategies for protection of both terrestrial and aquatic values in BC. Lack of well-tested, sensitive, measurable indicators as well as a system for their broad application will greatly constrain our ability to evaluate the environmental implications of the results-based FRPA. In addition, the Department of Fisheries and Oceans recently released The Wild Salmon Policy in June 2005. The goal of this policy is to restore and maintain healthy and diverse salmon populations and their habitats for the benefit and enjoyment of Canadians, in perpetuity. Since most of BC’s watersheds provide critical habitat for salmon and given the close linkage between land and water systems, it has been commonly accepted that the most effective approach for protection of salmon habitat is through sustainable forest or land management. However, implementing such an approach requires a deeper understanding of the relationship between aquatic habitat indicators and forest harvesting. Thus, there is clearly a need to conduct scientific research to assess the relationship between aquatic habitat indicators and forest management to support implementation of FRPA and the Wild Salmon Policy. There are many watershed indicators that include hydrology, water quality, biology and channel morphology. After reviewing and comparing the above-mentioned indicators, MacDonald (1994) suggested that those stream morphology-related aquatic habitat indicators (i.e. in-stream wood, pools, substrates, embedment etc.) are likely more sensitive to forest management and land use changes, and they can also be easily measured and monitored. However, many studies have demonstrated that aquatic habitats are influenced by factors operating at multiple spatial scales (Allen and Johnson 1997; Johnson and Covich 1997; Richards et al., 1997; Stein et al., 2001; Schreier and Brown 2001; Benda 1999). At the watershed scale, geomorphology and climate affect stream hydrology, sedimentation, nutrient input and channel morphology. At more local scales, land use, through alternation of riparian vegetation and stream conditions, can have significant influences on in-stream wood recruitment and its associated habitat attributes (Wei 2003; Chen et al. 2005) as well as macroinvertebrate assemblages (Richards and Host 1994). Thus, stream habitat indicators must be assessed at both reach and watershed scales. A big challenge in watershed management is separating the impacts of forest disturbance at both the reach and watershed scales. Johnson and Gage (1997) provided a useful review on various research methods for understanding landscape or watershed influence upon aquatic ecosystems. These methods include spatial statistics, multivariate statistics, structural equation modeling and fuzzy logic. Among those methods, multivariate statistics combining with GIS spatial analysis has been extensively used, and was approved to be a robust approach (Allen et al., 1997; Richards et al. 1996; Stewart et al., 2001). In this research, we propose to use GIS and multivariate statistical analysis to assess the relations between aquatic habitat indicators and forest harvesting at both stream reach and watershed scales in the BC interior. GIS is a powerful tool for development and analysis of spatial data, enabling researchers to address multi-scale issues much more effectively (Wei and Davidson 1999; Allen and Johnson 1997). However, the utility of GIS is largely dependant upon the quality of data and applied methodologies. In this proposed research, GIS and remote sensing technologies will be used to generate data on watershed properties and land-use changes at both the stream reach and watershed scales. This data will then be used to test their statistical relations to stream habitat indicators obtained from extensive field surveys. Our key purpose of this project is to test several aquatic habitat indicators and their sensitivity to forest harvesting. This proposed project will complement other current research that is being conducted by other hydrologists or stream ecologists in BC. For examples, Dan Hogan from Ministry of Forests has established long-term monitoring sites to assess large woody debris and channel morphology in various biogeoclimatic zones. Field and statistically-tested data from our study will provide important causal information which can be utilized to interpret their monitoring results. Dr. Brain Heise from the Thompson River University and Ian Sharpe from Ministry of Environment have funding from FSP to assess impacts of timber harvesting on macroinvertebrate assemblages in the selected BC interior forest watersheds. Both our proposed research and Dr. Heise’s research can potentially be combined to refine stream ecological indicators. In addition, our proposed research can provide benefit to a study being conducted by Dr. John Richardson from University of British Columbia which focuses on impacts of riparian management on stream ecology. The Ministry of Forests and Range through the FRPA Resource Evaluation Program is currently in the process of developing, testing and applying various indicators and measures to evaluate the effectiveness of FRPA in the stewardship of forest resource values. This research will compliment these efforts and will further develop science-based tools that could be used to evaluate the function and condition of forested watersheds within the BC interior. I currently hold a Research Chair in Watershed Management at the University of British Columbia Okanagan (UBCO), and I am also a working group member with FORREX’s Watershed Management Extension Program. These positions provide me with a unique opportunity to collaborate with the forest industries and government agencies. Such collaboration is needed to identify research sites and to access to the various GIS data for this proposed project. In addition, UBCO (formerly Okanagan University College) has received $1.2milliom from the Canadian Foundation for Innovation (CFI) and the British Columbia Knowledge Development Fund (BCKDF) for watershed research facilities. This, together with our newly-established GIS lab significantly boosts our research capacity to conduct watershed-related research.
Related projects:  FSP_Y082282FSP_Y093282
Contact: Wei, Adam, (250) 807-8750,


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Updated August 16, 2010 

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