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Lecture 20 Spatial Decision Support Systems (SDSS). Outline: Introduction Principles and theory Examples Online SDSS. Introduction. The ultimate application? OR... is this where the previous 9 (or 19) lectures have been leading? Use of GIS for environmental applications includes:
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Lecture 20Spatial Decision Support Systems (SDSS) Outline: Introduction Principles and theory Examples Online SDSS GEOG2750 – Earth Observation and GIS of the Physical Environment
Introduction • The ultimate application? OR... is this where the previous 9 (or 19) lectures have been leading? • Use of GIS for environmental applications includes: 1. data management 2. characterisation and assessment 3. modelling and spatial analysis 4. management and decision support • Applications 1 thru 3 culminate in 4... the end use? GEOG2750 – Earth Observation and GIS of the Physical Environment
Application or decision support? • An application may end at any point • CORINE, GRID, GEMS, etc. end at 1 • descriptive/mapping exercise and EA may end at 2 • predictive modelling exercise may end at 3 • BUT they must all start at 1 and work through these stages in sequence • The ultimate end application must be decision making (i.e. management) and use in support of decisions made GEOG2750 – Earth Observation and GIS of the Physical Environment
Aims of EnvSci • Aims of environmental science: • to accumulate knowledge pertaining to the environment? • to understand environmental processes and linkages? • Objectives of environmental science: • gather data pertaining to environmental phenomena and processes via empirical investigation? • to develop theories encompassing environmental themes? • i.e. to gain understanding and insight through study GEOG2750 – Earth Observation and GIS of the Physical Environment
Aims of EnvMan • Aims of environmental management: • to prevent environmental deterioration and degradation? • to promote sustainable use of the environment? • to prevent over use or exploitation of natural resources? • to preserve environmental diversity? • Objectives of environmental management: • to control the environment and/or our influences upon the environment via direct or indirect action? • i.e. putting environmental science to work! GEOG2750 – Earth Observation and GIS of the Physical Environment
Decision making or support? • Decision making vs decision support • GIS can provide certain tools for assisting in the decision making process • i.e.maps/displays as means of visualising the problem • overlays as means of defining relationships • modelling as means of predicting outcomes • etc GEOG2750 – Earth Observation and GIS of the Physical Environment
…the answer • GIS functions on their own are NOT decision making tools... • (i.e. they only ASSIST in the decision making process) • ...therefore, GIS is not a decision making tool, it is a decision SUPPORT tool GEOG2750 – Earth Observation and GIS of the Physical Environment
Decision making • Decision making: • a decision is a choice between alternatives to meet specific objectives • the alternatives may represent: • different courses of action • different hypotheses • different use of a geographical entity • etc. GEOG2750 – Earth Observation and GIS of the Physical Environment
Decision objectives • Objectives are governed by management goals and in turn determine the range of alternatives • e.g. identify areas of high risk in soil erosion example in order to address the goal of preventing soil erosion • resulting alternatives may be different maps representing different management plans • Process governing the way decisions between alternatives are made is the “decision rule” GEOG2750 – Earth Observation and GIS of the Physical Environment
Conflict! Making decisions to meet specific objectives often involves CONFLICT Solving these conflicts is the art of good decision making GEOG2750 – Earth Observation and GIS of the Physical Environment
Why GIS is not decision making • GIS is not a decision making tool kit • to make (good) decisions requires: • knowledge & foresight • insight & intelligence • expertise, etc. • i.e. rational choice between alternatives (especially where conflicts are present) • GIS does not provide the above, BUT it can fulfil important role in decision making by providing decision support GEOG2750 – Earth Observation and GIS of the Physical Environment
Decision support is… • Decision support: • role of aiding the decision making process • simplest level: • expert advice regarding a decision between alternatives • most complex level: • dedicated computer systems • i.e. decision support systems (DSS) GEOG2750 – Earth Observation and GIS of the Physical Environment
Definition of a DSS • In general terms, DSS are: • computer-based systems • dedicated to a restricted but well defined area of application • systems incorporating modelling and analysis with data and database management systems • systems which do not make decisions, but facilitate logistics of decision making process • interactive systems that help decision maker systematise decision making process • providers of custom-built information • providers of user-friendly GUI with short response times GEOG2750 – Earth Observation and GIS of the Physical Environment
Developing Spatial DSS • The role of GIS? • GIS is an INCREDIBLY USEFUL tool • GIS toolbox can be used to develop SDSS • SDSS retain the general characteristics of basic DSS but in addition they include: • spatial data input capabilities • storage of complex structures common in spatial data • analytical techniques unique to spatial data • cartographic output GEOG2750 – Earth Observation and GIS of the Physical Environment
Basic SDSS structure Models G.I.S Database User Interface User: expert knowledge GEOG2750 – Earth Observation and GIS of the Physical Environment
GIS as SDSS? • GIS fits nicely with additional requirements of a SDSS, but still does not meet the overall requirements of a DSS • GIS do not include expert knowledge • GIS do not possess artificial intelligence (AI) • GIS have only limited spatial analysis functionality • GIS are not very user friendly • GIS are not dedicated systems GEOG2750 – Earth Observation and GIS of the Physical Environment
Question… • How can we address these short-comings of GIS in developing SDSS? GEOG2750 – Earth Observation and GIS of the Physical Environment
Example: nuclear waste disposal • Example of a facilities location exercise involving multiple and conflicting criteria • ideal example application for a SDSS from initial site survey through to public inquiry • problem has been approached by NIREX since 1981 and they are now on their fifth attempt • four previous failures due to poor information, poor public communication, obsession with engineering issues, etc. • why didn't they listen to me? GEOG2750 – Earth Observation and GIS of the Physical Environment
Nuclear waste… the problem GEOG2750 – Earth Observation and GIS of the Physical Environment
Nuclear waste disposal… how? GEOG2750 – Earth Observation and GIS of the Physical Environment
A GIS approach… • Basic GIS/MCE site search: • identify screening (constraint) factors and their threshold criteria and use map overlay to identify areas satisfying above constraints • identify multiple site-based factors on which to optimise • establish weighting scheme for factors • run MCE routine to identify optimal or near-optimal sites • run sensitivity analyses and identify final sites • pass the buck! GEOG2750 – Earth Observation and GIS of the Physical Environment
Advantages… • Advantages of such an approach are: • good at deterministic area screening • provides an application framework for MCE • MCE provides GIS with spatial analysis functionality • provides a rational and objective approach GEOG2750 – Earth Observation and GIS of the Physical Environment
Nuclear waste disposal… where? GEOG2750 – Earth Observation and GIS of the Physical Environment
Role of SDSS • SDSS may be used throughout the site selection decision making process as follows: • aiding initial decision making process • public information, consultation and participation • decision support at public inquiry GEOG2750 – Earth Observation and GIS of the Physical Environment
Online SDSS • If public participation is goal then need to: • maximise access to data and tools • maximise scope for public participation • at all stages of planning process • at all stages of decision process • Utilise web-based GIS for SDSS GEOG2750 – Earth Observation and GIS of the Physical Environment
Examples web-based SDSS • Virtual Slaithwaite • WOODS • Nuclear waste siting • Wilderness mapping GEOG2750 – Earth Observation and GIS of the Physical Environment
Conclusions • SDSS is utlimate end application of environmental GIS • development of GIS-based SDSS • online SDSS GEOG2750 – Earth Observation and GIS of the Physical Environment
Practical • Running online SDSS • Run the eMapScholar online GIS exercise • http://www.ccg.leeds.ac.uk/teaching/nuclearwaste/ • You must: • Complete the full exercise • Fill in the profile form • Fill in the feedback form GEOG2750 – Earth Observation and GIS of the Physical Environment