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This introductory lecture provides an overview of watershed analysis in forest engineering, emphasizing its importance in managing environmental impacts. We explore the early management practices and regulations that shaped current approaches, highlighting the significance of spatial analysis in understanding watershed dynamics. Key concepts include data collection for individual points in a watershed, calculating processes affecting streams, and using GIS tools like spreadsheets for effective planning. The course will develop GIS skills applicable to various environmental issues and provide hands-on experience with real-world problems.
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FE 423 - Watershed AnalysisLecture 1a - Overview Finn Krogstad UW Forest Engineering http://students.washington.edu
OVERVIEW • why - • what - • when - • where - • how - • who -
EARLY MANAGEMENT • Management was done with little consideration of environmental impacts
Early Regulations • Case-by-case evaluation of roads, harvests, and locations • Still dominates forest management today
Watershed Analysis • APPROACH - basin specific • where are the hazards • what are they sensitive to • will they reach the stream • are there sensitive reaches • are vulnerable fish there • do inputs exceed background
Watershed Analysis • PROBLEMS • Massive expert time • Site-by-site investigation • Stop being watershed specific • Site, not landscape plans • Is plan A worse than plan B?
OVERVIEW • why - spatial approach • what - • when - • where - • how - • who -
WATERSHEDS • Spatial Heterogeneity • Water Flows Downhill
EACH POINT HAS UNIQUE: • Vegetation • Soil • Slope • Aspect • Upslope Area • Distance to Stream • Management
‘DOWNHILL’ IMPACTS • Saturating Hillslopes • Erosion Runoff Filtering • Stream Flow Volumes • Stream Width & Depth • Sediment Supply • Fish Habitat
WE NEED 1a. Data for each point in the watershed 1b. Calculate processes at each point 2a. Sum outputs from upslope area 2b. Sum ‘delivery costs’ to stream
Spreadsheets - The Most Powerful Scientific Tool Ever Developed 1. Bring in data 2. Run calculations 3. Display results Originally was: Programming for Accountants
GRID: the Spreadsheet for Landscapes 1. Bring in spatial data (soils, vegetation, topography, ) 2. Run equations 3. Display results ArcView: not just pretty pictures
Gridding the World Watershed Analysis: in GRID • data for each point • calculation at each point • … along path to the stream • accumulating upstream inputs • accumulating different inputs • compare management plans
OVERVIEW • why - spatial approach • what - downhill in GIS • when - • where - • how - • who -
OVERVIEW • why - spatial approach • what - downhill in GIS • when - schedule • where - • how - • who -
SYLLABUS OSB
OVERVIEW • why - spatial approach • what - downhill in GIS • when - schedule • where - OSB 111 • how - • who -
SYLLABUS Instructors: Finn Krogstad, Peter Schiess Grading:FE423: three exams (33% each)FE523: three exams and a project (25% each) Lectures: Tuesday & Thursday, 9:30-11:20, in OSB 111 (except first day in AND 302) Exams:Each exam will include an in-class and a take-home part. The in-class part is open book, open note, pencil-and-paper discussion of grid-based solution of watershed problems. The take-home part which will require solution of problems. Practice Problems:Each lecture will include a set of problems to provide hands-on experience in the grid-based approach to solving watershed problems. These problems are not handed in, but the exams will look much like these problems, and will assume that students have completed all problems.
READINGS • Hard copy of the online helpCell Based Modeling with GRID • People without ArcView experienceGetting to know ArcView GIS • Another view of Spatial Analyst Extending Arcview GIS • Some Hydrology and Geomorphology Water in Environmental Planning, Watershed Analysis Manual (WFPB) Geomorphology (Chorley, et al)
OVERVIEW • why - spatial approach • what - downhill in GIS • when - schedule • where - OSB 111 • how - syllabus • who -
Why Watershed Analysis in GRID? • PROBLEMS • not a survey class: an approach, not ‘facts’ • learning GIS: requires work • existing software: more accurate ‘black boxes’ • ADVANTAGES • quantitative approach: actually ‘say something’ • insight into process: applicable to many issues • GIS skills: applicable to other types of problems
Should you take this course? • Spatial Hydrology • Landscape Scale • More GIS
Discussion Problems:for Thursday, try and be ready to discuss the following Make a spreadsheet that will estimate the peak flow Q5=.157*A.9*Pa1.35*F-.21 for a five year storm in Region XII, using a table of road crossings with their respective contributing area A, percent forest cover F, and annual rainfall Pa.