Presentation on theme: "GIS for Environmental Science"— Presentation transcript:
1 GIS for Environmental Science ENSC 3603Class 72/03/09
2 Today's Objectives Quiz GIS Data GeoStor Quick Start Guide NRCS Web Soil SurveyVector DataArcGis, ArcCatalog
3 GIS Data GeoStor 5 quick start guide NRCS Web Soil Survey NRCS Web Soil Survey
4 DataThematic LayersA GIS stores information about the world as a collection of thematic layers that can be linked together by geography.
5 DataGeographic data record the locations and characteristics of natural features or human activities that occur on or near the Earths surface.Data Types:Vector Raster Surface
6 Vector DataVector Data: A conceptual representation of geographic features.Vector Data Model: Object based approach to represent discrete objects.Vector Data Model Concepts use graphical elements:PointsLines or arcsPolygons or areasThese are also known as Feature Classes
7 Reality as Vector Data Points (Man-holes) Lines (Roads, Sewer lines) Real-World entities are abstracted into three basic shapesPoints(Man-holes)Lines(Roads, Sewer lines)Polygons(Wetlands, Fields,Buildings)
11 Vector DataPolygon: Washington County Soil Series
12 Vector DataConverted to Vector dataStructureRaster data Structure
13 Vector DataFeature classes pertain to a particular theme such as vegetation, land parcels, drainage and transportation etc.Feature classes are organized into layersLayers only have one type of graphical element.
14 Vector Data Representing vector data differently at different scales: Cartographic generalization – line and area objects are represented by more coordinates at a large scale than at a small scale.Cartographic symbolization – Vector data are represented by different symbols that visually distinguish them from one another
15 Vector Data Topology: Spatial relationships Adjacency: neighborhood Containment: Inclusion of one spatial object within anotherConnectivity: Linkages among spatial objects
16 Vector Data Topology: Spatial relationships Adjacency: neighborhood Polygon C is Adjacent to Polygons B and D
17 Vector Data Topology: Spatial relationships Containment: Inclusion of one spatial object within another.Polygon A is Contained within Polygon B
18 Vector Data Topology: Spatial relationships Connectivity: Linkages among spatial objects.Point A is Connected to Point BAB
20 Vector Data Input functions Digitizing tables Image scanning Importing data
21 Vector Data Data input functions: Acquisition by digitizing, purchasing, collecting new data by GPS, surveying or photogrammetric and remote sensing methodsEditing to clean and inspect data.Formatting or translating to convert data to a specific physical database format.Linking graphical data to associated attribute data.
22 Vector Data Analysis functions: Nontopological Analysis: Attribute database queryStructured Query Language (SQL)Address geocodingOr Address matching, TIGER filesArea CalculationStatistical computationMean, max, min and standard deviation computed for items in attribute tables.
23 Attribute database query, Structured Query Language (SQL)
24 Attribute database query, Structured Query Language (SQL) Map Result
25 Geocoding Database of address used to Map locations on a map. Database of address used toMap locations on a map.Mapquest uses Geocoding to findlocations.
26 Statistical computation, Mean, max, min and standard deviation computed for items in attribute tablesField F1Soil pH
27 Vector Data Topological Analysis Layer-based Analysis Reclassification Aims to reduce categories of attribute dataLayer-based Overlay analysisTopological Overlay Operators for polygon on polygonUNION: Keeps all area in both layersINTERSECT: Keeps only parts of the first layer falling within the second layerIDENTITY: keeps all layer featuresCLIP: Cuts out a piece of the first layer based on the secondERASECOV: erase part of first layer based on the secondSPLIT: divides the first layer based on the secondNetwork analysis
28 Vector Data Network analysis Linear features that are interconnected Examples, highways, railways, rivers transit routes utility distribution systems.Example problem: Find shortest route between two points.Line segments and junctions can have resistance.
30 Vector Data Feature-based analysis A Buffer is a zone with a specified width that surrounds a spatial feature.BufferingUsed for neighborhood analysisFeature-based overlay analysisExample, point in polygon
31 Vector DataBuffering around a pointBuffering around lines
32 Vector Data Overlay analysis Represents the world in layers Combines human/social with environmentalData must be measured, generalized, and quantifiedBoth visual and analytical analysisTypes Visual, Boolean, Arithmetic
34 Class ProjectA 200 word statement describing a problem to be addressed by the project. Include an:IntroductionObjectivesMethods – Data, Software, AnalysisReferencesExample found at:
35 For Next time Chapter 5 in Lo (2007) Project proposal due February 5th ESRI Module 2 due
36 "Focus not on the commotion around you, but the opportunity ahead of you." - Arnold Palmer "Achievement is largely the product of steadily raising one's levels of aspiration and expectation." - Jack Nicklaus