NR 422 Data Types II Jim Graham Spring 2010

Simple Data Types Point (2d or 3d) –Coordinates with attributes Polyline (2d or 3d) –Points collected by line segments –2 lines max per point Polygon (2d) –Closed polylines Rasters (2d, 3d elevations) –Points in a grid (one attribute or lookup) Triangulated Irregular Networks (2d or 3d) –3 lines max per point

Triangulated Irregular Networks TINs A “mesh” of triangles Vertices Nodes Edges, Line Segments, Links Arcs

TINs – Complex but Flexible

IDRISI

3d Graphic Solids are TINs! DEMs: 2 triangles per pixel

Topography: Atoll

Water Resource Management Improving Environmental Site Management Through the Use of Internet Resources Authors: Gary Whitton, Clayton Cranor, Michael Lilly, David Nyman

Applications Water resource management Water dynamics (tsunamis) Erosion Earthquakes “Volume” modeling in oceans Species relationships Decease transmission

Describing 3d Structures Contours: –Constant elevations –Variable horizontal resolution Rasters: Constant resolution –Variable elevations –Constant horizontal resolution TINs: –Variable elevations –Variable horizontal resolution

More Complex Data Types Features –Collections of points, polylines, polygons Networks –Related polylines and/or TINs Raster Mosaics –Overlapping rasters Spatial Databases/Datasets –All types and relationships

Complex Features Polyline –Rivers & Streams: Connected networks of “reaches” –Attributes include: quantity of flow Polygons –Groups of islands: Hawaii –“Holes”: Lakes on surfaces Islands on lakes

Networks Spatial, relationships, or both Basically large, complex polylines Or relationships Trophic relationships Bilogical Network Analyais –Gene flow Related to “Graph Theory”

Networks Streams and rivers –Water supply –Flood prediction –National Hydrology Network Transportation (mature): –Freeways, highways, and roads –Ships –Planes Disease vectors (developing) Natural Resource Management (new)

Problems Shortest path Network flow (traffic, water) Transport Problem: Optimal movement of goods

Shortest Path Problem What is the shortest path from 6 to 2? What is the shortest path to visit all nodes starting at 1?

Network Analysis Vertex: Sum of inputs and outputs = 0 Edge: Has maximum capacity Source: Inputs to network Sink: Outputs from the network

Spread of Content in a Network Conserved: –Water –Soil –Nitrogen Non-Conserved: –Infectious deceases –Food (trophic levels)

Global Water Cycle

West Nile Virus US with crow migrations

Link Analysis Seeks relationships between lots of nodes in the network Banks, search engines, fraud, spamming Epidemiology

Trophic Relationships Network Analysis of the St. Marks Wildlife Refuge Seagrass Ecosystem.

Networks of Habitat Trees Networks of roosting trees for bats Brisbane, Australia

Social Networks Social networks of wildlife stakeholders: Insights from waterfowl hunting and furbearer trapping conflicts in New York

Network Analysis in NRM Social Movements and Ecosystem Services-the Role of Social Network Structure in Protecting and Managing Urban Green Areas in Stockholm Management of Natural Resources at the Community Level: Exploring the Role of Social Capital and Leadership in a Rural Fishing Community 'Who's in the Network?' When Stakeholders Influence Data Analysis

2t15n46739g6/ 2t15n46739g6/ stochastic network analysis Serfozo, R Introduction to Stochastic Networks. Springer: New York. Sympatry Inference and Network Analysis in Biogeography