Geographical information systems and remote sensing in inland fisheries and aquaculture

Table of Contents

Dr Geoffery J. Meaden
33 St Stephen's Road
Canterbury, Kent CT2 7 JD
Dr James M. Kapetsky
Inland Water Resources and Aquaculture Service
FAO Fisheries Department

Reprinted 1995

The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.

ISBN 92-5-103052-9

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Food and Agriculture Organization of the United Nations Rome, 1991


The FAO Inland Water Resources and Aquaculture Service has been active for some years in promoting the use of remote sensing and geographical information systems in fisheries and aquaculture. Promotional activities have been carried out by holding training courses and workshops. However, of necessity, the attendance is limited. A larger audience can be reached only by the distribution of technical material. This document was prepared to meet the need for a reference to remote sensing and geographical information systems that maintains a balance between the technologies and their applications in fisheries and aquaculture. Comments are welcome. Information about related, on-going work can be obtained by writing to:

Chief, Inland Water Resources and Aquaculture Service
FAO, Via delle Terme di Caracalla
00100 Rome Italy.


FAO Fisheries Department
FAO Regional Fishery Offices
Directors of Fisheries
CIFA Mailing List
IPFC Mailing List
COPESCAL Mailing List

Meaden, G.J.; Kapetsky, J.M.
Geographical information systems and remote sensing in inland fisheries and aquaculture.
FAO Fisheries Technical Paper. No. 318. Rome, FAO. 1991. 262p.
The rapidly rising world population is causing both a pressure on land and water space and the need to greatly increase food output. A realistic and practicable way of supplying more food protein is to increase fish production through the extension of aquaculture and inland fisheries. Since production sites for these activities need to satisfy fairly complex location criteria, it is important that suitable areas are identified and preferably designated in advance. The location criteria which control aquaculture and inland fisheries are identified and described. These mainly consist of physical and economic considerations though social factors may be important. It is necessary to obtain data to allow for its mapping. The various alternatives for assembling this data are described.
Two fields of applied science and technology have recently emerged which, when used in combination, can greatly assist in the spatial decision-making process. The fundamentals of the first of these, remote sensing, are described giving particular emphasis to the commercial, high resolution environmental satellites and the sensing devices which they carry. The manner in which the aerial photographic and digital images which are produced can be processed and applied to the search for optimum fish production locations is described, and then indications are given as to where and how remotely sensed data can best be procured. Once the various types of locational data are assembled, the necessary maps on which location decisions are made can be drawn up. This task can be greatly expedited by using the second applied science and technology field, that of “geographical information systems”. This emerging methodology relies on the increasing power of the computer to process vast amounts of spatially referenced and encoded data in such a way as to produce any desired maps, tabular or textual output, using a large array of ways to manipulate the data. The required computer hardware and software are reviewed, including examples where appropriate, and we show the considerations which are necessary in setting up a geographical information system for the development and management of aquaculture and inland fisheries. We conclude by giving an divergent selection of relevant case studies.


A number of recurrent and worrying themes increasingly intrude into the comparatively comfortable lives of so many of us - famine, environmental degradation, climatic change, desertification, poverty,inequality, population pressures - and so on. There is a sense in which this study is about all of these things. At the root of many of the problems lies the inability of people to provide for themselves at a most basic level - that is to provide a suitable means of producing sufficient food.

A proliferation in the production of fish may well be part of the solution to this problem. Most readers of this study will be aware that in a few areas of the world, notably in eastern and South-East Asia, intensive and extensive forms of fish rearing have been successful over a very long period of time. Attempts have been made to replicate this success elsewhere but these efforts have had surprisingly little impact, except where aquaculture has been initiated in a highly commercial, intensive form. So, throughout much of the developing world, even where fish production has a great potential to be enhanced, there remains a dominant reliance on imported fish products whose origins are mainly from the decreasing wild-catch fisheries.

One of the barriers both to increasing fisheries output and to enhancing the diffusion processes concerning aquacultural techniques, has been the lack of data on, and methods for, optimizing production locations. A reason for this is that we have generally failed to grasp the significant part which spatial variations, in either physical, economic or social factors, play in the success of a production enterprise. This study is an attempt to show how two rapidly emerging technologies can be utilized to greatly speed up, and make more efficient, location optimizing processes, and how the technologies can allow for a thorough examination of the many spatially variable factors which might affect or control fish production.

The study is written primarily for a variety of personnel in fisheries departments, both in the developing and developed countries. However, since it covers a lot of material relevant to remote sensing (RS) and geographical information systems (GIS), then it could be of value to, amongst others, geographers, agriculturalists, location analysts and to any persons interested in promoting, learning or teaching about these two emerging technologies. We have aimed the study at about undergraduate level, though it could easily be followed by a wider audience since we very deliberately strived to avoid unnecessary jargon and those many acronyms which are so beloved in the worlds of remote sensing and computing! We have also provided further basic reading on particularly important areas covered by the script. Though we are aware that the study will, in some parts, quickly become dated, we are confident that many of the main ideas will enjoy a longer term of relevance, and that a small amount of judicious research could soon make up for the fact that scientific implementation has overtaken us.

After a brief introduction, which sets the scene on both the importance of increasing fisheries production and on securing and optimizing sites for this production, Chapter 2 explains, in varying degrees of detail, the factors which control fish production in both the aquaculture and inland fisheries environments. A large number of mostly physical and economic production functions are identified and discussed. Before any spatial optimization of production can occur, it is necessary to procure relevant data. In Chapter 3 we detail collection techniques for obtaining both primary and secondary data and we suggest that, where this data is lacking or unsuitable, then use might be made of “proxy” data. However, one of the major data sources, remote sensing, is given a complete chapter (No.4) since the data obtained is likely to prove of paramount importance when locations are being considered in much of the developing world, i.e. where traditional spatial data may be non-existent. Additionally, RS data can easily be secured in a favourable, digitized form. We give some background to thetheory and history of RS, we look at different satellites and sensing systems and we briefly cover some of the data processing procedures. We then examine some of the practical and potential uses of RS plus the methods of acquiring and using the necessary imagery. Chapter 5 takes an in-depth look at those traditional mapping sources which have been used in location analysis, looking first at both topographic and thematic maps generally, and then at how thematic maps can be specifically utilized to provide useful information for location optimizing in aquaculture or inland fisheries, or as a source of input data for GISs. In Chapter 6 we examine GISs in some detail, showing first their evolution and development and then going through a step-wise description of how the system's function and the necessary requisites for this functioning in terms of hardware and software. We also show benefits and problems of using GIS and the necessary considerations which must be given before adopting a GIS. We conclude with a variety of case studies which are aimed at showing applications of both RS and GIS to aquaculture and inland fisheries.

Hyperlinks to non-FAO Internet sites do not imply any official endorsement of or responsibility for the opinions, ideas, data or products presented at these locations, or guarantee the validity of the information provided. The sole purpose of links to non-FAO sites is to indicate further information available on related topics.


  1.1 Meeting Food Needs
  1.2 The Varying Nature of “Space” Needs
  1.3 Pressures on the Available Space
  1.4 The Importance of Site Selection and Procurement
  1.5 Towards Handling the Complexities of the Data
  2.1 Production Functions
  2.2 The Production Function Mix Controlling Aquaculture or Inland Fisheries
  2.3 The More Important Production Functions Controlling Aquaculture and Inland Fisheries
    2.3.1 Water Quality
    2.3.2 Water Temperature
    2.3.3 Water Quantity
    2.3.4 Transport Accessibility
    2.3.5 Market Accessibility
  2.4 Considerations of Some Other Spatially Variable Production Functions
    2.4.1 Climatic Factors
    2.4.2 Agglomeration
    2.4.3 Soils
    2.4.4 Relief (Topography)
    2.4.5 Land Costs (or Rent)
    2.4.6 Availability of Credit (or Capital)
    2.4.7 Availability of Fertilizer and Agricultural by-Product Inputs
    2.4.8 Availability of Extension Services
    2.4.9 Current Inland Fishery Levels
  2.5 Other Production Functions Showing Some Spatial Variability
  3.1 Introduction
  3.2 Obtaining Primary (Directly Sensed) Data
    3.2.1 Techniques for Collecting Primary Data
    3.2.2 The Application of Primary Data Collecting Techniques to Aquaculture and Inland Fisheries Direct Mapping and Field Sketching Photography Interviewing Questionnaires Measurement
  3.3 Obtaining Secondary Data
    3.3.1 The Format and Sources of Secondary Data
    3.3.2 The Application of Secondary Data to Delineating Production Function Variability
    3.3.3 Sources of Maps as a Secondary Data Source
  3.4 “Proxy” Data Sources
  4.1 Introduction
  4.2 The Development of Remote Sensing
  4.3 Electromagnetic Radiation - The Basis of Remote Sensing
    4.3.1 Incident Energy
    4.3.2 Effects of Atmosphere
    4.3.3 Ground Influences
  4.4 Remote Sensors
    4.4.1 Framing Sensor Systems
    4.4.2 Framing System Films
    4.4.3 Scanning Sensor Systems

Passive sensors

Active sensors
  4.5 Remote Sensing Platforms and Sensors Being Carried
    4.5.1 Sensor Platforms
    4.5.2 Types of Environmental Satellites

Geostationary satellites

Near-polar orbiting satellites
    4.5.3 The Major Operational Environmental Satellites

Landsat 4 and 5

SPOT - 1

Marine Observation Satellite (MOS-1)

ESA Remote Sensing Satellite (ERS-1)

    4.5.4 The Major Environmental Remote Sensors

Landsat 4 and 5 sensors

SPOT-1 sensors

ERS-1 sensors

MOS-1 sensors

Kosmos sensors

Other sensors of interest to aquaculture and inland fisheries
  4.6 Data Processing of Remotely Sensed Imagery
    4.6.1 Image Pre-Processing
    4.6.2 Image Display and Enhancement
  4.7 The Potential Applications of Remote Sensing to Aquaculture and Inland Fisheries
    4.7.1 Water Quality
    4.7.2 Water Temperature
    4.7.3 Water Quantity
    4.7.4 Economic Production Functions Related to Distance Factors or Population Distributions
    4.7.5 Climatic Factors
    4.7.6 Soils
    4.7.7 Relief
    4.7.8 The Existence of Shelter for Cage Culture
    4.7.9 Bathymetry
  4.8 The Acquisition of Remote Sensing Information
    4.8.1 Remotely Sensed Product Types

Digital data or computer compatible tapes (CCTs)

Photographic products
    4.8.2 Product Availability
    4.8.3 Guidance and Support Facilities

Support given by the major companies and organizations

Other sources of guidance and support
  4.9 Problems of Utilizing Remote Sensing Methodologies
    4.9.1 The Variable Amount of Accessible Data
    4.9.2 The Necessity for Ground Truthing
    4.9.3 Accessibility to Suitable Hardware
    4.9.4 Spatial Resolution
    4.9.5 Commercialization of RS Products
    4.9.6 Long Term Planning and Payload Uncertainty
  4.10 Some Relevant Observations on the Future of Remote Sensing
  5.1 Introduction
  5.2 Topographic Maps
  5.3 Thematic Maps
    5.3.1 Types of Thematic Maps
    5.3.2 Thematic Map Considerations for Aquaculture and Inland Fisheries
  5.4 The Derivation of Some More Complex Thematic Maps
    5.4.1 Water Quantity Maps
    5.4.2 Water Temperature Maps
    5.4.3 Maps Showing the Availability of Underground Water
    5.4.4 Relief Maps
    5.4.5 Land Cost Maps
    5.4.6 Maps Showing Access to Road Transport
    5.4.7 Maps Showing Distance From Catering Markets
  6.1 Introduction
  6.2 Defining GIS
  6.3 The Evolution of GIS
    6.3.1 Factors Causing the Recent Expansion of GIS The proliferation of data

The reduction in computing costs

The integration of parallel developments

Increased opportunities for GIS
    6.3.2 The Historical Development of GIS
  6.4 The Functioning of GIS
    6.4.1 Data Input and Encoding

Data capture methods and hardware used

The structure of spatial data

Linking spatial and non-spatial data

Efficient data storage structures
    6.4.2 Data Manipulation

Data validation, correction and editing

Structure conversion

Geometric conversion, map sheet manipulations or transformations

Map overlay, merge or integration

Generalization and classification

Other manipulations
    6.4.3 Data Retrieval
    6.4.4 Data Analysis
    6.4.5 Data Display

Types of display

Devices used for capturing display
    6.4.6 Data Base Management Systems
  6.5 GIS Software
    6.5.1 An Introduction to GIS Software
    6.5.2 The Varied Characteristics of GIS Software

Software evolution

Software ownership

Linkages between companies or organizations

Pricing policies

Software functional range

Other variations in GIS software
    6.5.3 The Capabilities of Some Typical GIS Packages




  6.6 The Benefits and Problems of Using GIS
    6.6.1 The BenefiZts of GIS
    6.6.2 The Problems of GIS
  6.7 Considerations in Choosing a GIS
    6.7.1 Why is a GIS Needed?
    6.7.2 How Should a GIS Fit Into An Organization?
    6.7.3 What Financial Considerations Should Be Made?
    6.7.4 What Sort of GIS Configuration Should We Adopt?
    6.7.5 What Sort of Software Should We Choose?
    6.7.6 What Are Our Personnel Needs?
    6.7.7 Procedures for Setting Up the GIS
  6.8 Guidance and Support for GIS
    6.8.1 Training in GIS
    6.8.2 Published Information on GIS
    6.8.3 Other Sources of GIS Guidance
  6.9 Future Trends in GIS
  Study 1    “The Preselection of Sites Favourable for Tropical Shrimp Farming”
  Study 2    “Feasibility of Using Remote Sensing to Identify the Aquaculture Potential of Coastal Waters”
  Study 3    “Remote Sensing and Model Simulation Studies of the Norwegian Coastal Current During the Algal Bloom in May 1988”
  Study 4    “Satellite Remote Sensing to Locate and Inventory Small Water Bodies for Fisheries Management and Aquaculture Development in Zimbabwe”
  Study 5    “Use of Remote Sensing in the Study of the Changing Shoreline of Sarykamysh Lake”
  Study 6    “Mapping Potential Effluent Pathways in the Long Point Region of Lake Erie from Landsat Imagery”
  Study 7    “A Geographical Information System for Catfish Farming Development”
  Study 8    “Where Should Trout Farms be in Britain?”
  Study 9 “    Microcomputer Spreadsheets for the Implementation of Geographic Inforamtion System for Aquaculture. A Case Study of Carp in Pakistan”
  Study 10    “A Geographical Information System for Aquaculture Development in Johor State”
  Study 11    “Use of Geographical Information Systems for Aquaculture Survey”
  Study 12    “Where are the best opportunities for fish farming in Ghana? The Ghana Aquaculture Geographical Information System as a decision-making tool”
  Study 13    “The Use of GIS for Coastal Resources Study: Some Case Examples”
  Study 14    Development of a Dispersant-Use Decision-Making System for Oil Spills in the U.S. Gulf of Mexico”
  Study 15    “Use of a Geographic Information System as a Conservation Tool for Rivers in Virginia, U.S.A.”
  Study 16    “Remote Sensing and Geographic Information System Techniques or Aquatic Resource Evaluation”


1.1The complexity and diversity of the aquaculture and inland fisheries production environments
1.2Some spatially related fisheries production factors for which data is mostly lacking - at the level of individual water bodies
2.1Typical production functions controlling aquaculture
2.2Production functions controlling the mariculture of oysters
2.3Some major water qualitative parameters controlling the fishery environment
2.4Summary of spatial considerations relating to water quality
2.5Factors causing spatial or temporal variations in water availability for fish production
2.6Flow rate variability for 9 selected hydrograph stations in England and Wales
2.7Summary of spatial considerations relating to water quantity
2.8Summary of spatial considerations relating to transport access
2.9Summary of spatial considerations relating to market accessibility
2.10Index properties of soils for freshwater fish culture
2.11Further production functions which may show spatial variability
3.1Techniques for primary data collection
3.2Major sources of secondary information on aquaculture and inland fisheries
3.3Selected list of national mapping organizations
3.4Map data products available through the national cartographic information center
3.5Examples of possible uses of “proxy” data
4.1Wave bands of the EMR spectrum of interest to remote sensing
4.2The main environmental polar orbiting satellite systems or programmes
4.3Landsat MSS bands and applications
4.4Bands and applications of the Landsat thematic mapper
4.5Characteristics of the HRVs on SPOT-1
4.6Bands, features and objectives of MOS-1 sensors
4.7Specification of cameras carried by Kosmos satellites
4.8Bands and measurements of the CZCS sensor
4.9Image processing functions found in many image processing systems
4.10Availability of Landsat photographic products
4.11Availability of SPOT photographic products
4.12Kosmos RS products available with prices(U.S.$)
4.13Landsat imagery prices for 1990
4.14Journals which are mostly devoted to remote sensing
5.1Smaller scale topographic map availability in West Africa
5.2Weightings allocated to river flow categories
5.3Weightings allocations to variability ratio classes
5.4Water “supply score” allocated by yield of aquifer
5.5Weightings allocated to classes of population density
5.6Weightings allocated to classes of land use capability
5.7Weightings given to different classes of road
5.8Scores allocated to the aggregate weighted totals of catering outlets
6.1A classification of GIS functions
6.2Main advantages of vector or raster graphical forms
6.3Survey of most GIS software available in 1989
6.4The range of functions available on version 2.0 of IDRISI
6.5Classification of features available on MundoCart/CD
6.6GIS functions supported by ARC/INFO relating to aquaculture and inland fisheries
6.7The main journals or trade magazines covering GIS
7.1Site selection matrix showing suitability for oyster culture
7.2Comparison of SWBs found in N.E. Zimbabwe using satellite and aerial photography
7.3Changes in basic characteristics of Sarykamysh Lake
7.4Characteristics of Frank in parish soils relative to catfish farming development
7.5Spatially variable production functions associated with trout farming in England and Wales
7.6Main criteria and components used in the GIS to identify opportunities for shrimp farming and for cage culture
7.7Hardware and software components used in the Johor aquaculture GIS
7.8Data encoding method and data sources used
7.9Aerial photo characteristics of aquatic macrophytes in Lake Marion


1.1Changes in world population size and distribution
1.2Trends in world fisheries - production and consumption
1.3Schematic diagram showing stages in spatial decision making
2.1Relationship between air and water temperatures for several sites in Britain
2.2Mean maximum, minimum and average monthly pond water and air temperatures for two sites in Malawi
2.3The annual variation of surface temperatures in a series of fourteen African lakes
2.4Frequency of river flow variability ratios for all gauging stations in England and Wales
2.5Flow diagram showing table trout marketing networks in England and Wales
2.6The fish marketing system in Malawi
2.7Relationship of phytoplankton production during the growing season to latitude
3.1Sketch map used to assess environmental quality and soil sampling points
3.2Methods for measuring water depth in a pond or reservoir
3.3Sample work sheet for a stream survey
4.1The electromagnetic spectrum
4.2The key features of the remote sensing data collection process
4.3Percentage of EMR able to pass through the atmosphere as a function of wavelength
4.4Spectral signature of various natural surface features
4.5The concept of IFOV and AFOV
4.6Optical mechanical scanning system
4.7Characteristics of a push broom radiometer
4.8The synthetic aperture radar system
4.9Positions and names of the five geosynchronous satellites providing meteorological data
4.10A typical orbital track for a polar orbiting satellite
4.11Typical orbital track for each orbit and for a repeat visit
4.12The Landsat swathing pattern and successive orbit paths
4.13Configuration of Landsats 4 and 5
4.14SPOT off-nadir revisit capabilities
4.15Stereoscopic viewing capabilities
4.16The configuration of MOS-1
4.17The configuration of ERS-1
4.18The flow of information in the remote sensing system
4.19Some important image processing techniques
4.20Mean reflectance values for several categories of land use
4.21Effluent and sediment yields in the Humber estuary in northern England
4.22Colour slice enhancement showing suspended sediments which allows the quantitative map to be compiled
4.23CZCS composite of bands 1,2 and 3 of the northern Adriatic showing chlorophyll concentrations in orange
4.24Development of a thermal plume in a lake in north Wales
4.25Density-sliced Meteosat images of Lake Chad in November and April
4.26Part of the referencing system used in the SPOT series
4.27Variations in Landsat data acquisition over the U.K. for 1976–1986
4.28Future developments in computer power, data acquisition and earth observation sensors
5.1Examples of large, medium and small scale topographic maps
5.2Examples of a key to a 1:25 000 scale topographic map
5.3Chorochromatic map showing land conservation areas in S.W. England
5.4Choropleth map showing changes in table trout production in England and Wales
5.5Volumetric divided circles showing the employment structure of S.W. England
5.6The construction of an isopleth map
5.7Economic potential isopleths for England and Wales
5.8Flowlines showing fish transport routes in Malawi
5.9Linear map showing water quantity variations
5.10Choropleth map showing water quantity variations in England and Wales
5.11Variability of river water flow in the north of England
5.12The efficiency of river water temperatures in northern England to provide for trout growth
5.13Best-fit curvilinear regression line fitted to curves or points showing salmonid growth rates against water temperatures
5.14The likelihood of being able to procure a licence to abstract underground sources of water in England and Wales
5.15Example of the map scored for “Access to Road Transport”
5.16Methodology used to establish scores for distance from catering markets
6.1Systems diagram to illustrate GIS
6.2Improvements in processor performance over time
6.3The breakdown of the U.K.GIS market till 1999
6.4An electro-mechanical digitizer plus various types of line-following cursors
6.5Flat bed and drum optical scanners
6.6Representation of the layers captured by RS or map digitizing
6.7Modes of organizing mapped data
6.8The creation of a topological data structure
6.9Steps in creating a topologically correct vector polygon data base
6.10Example of a run length code structure
6.11A raster mode map and its quadtree representation
6.12Summary of a vector to raster - raster to vector conversion
6.13Some fundamental geometric manipulations of GIS database files
6.14Venn diagrams to show the results of applying Boolean logic to two or more sets
6.15Some grid-based analytical techniques
6.16The operation and rotation of a drum plotter
6.17Flatbed plotter showing pen holder variations
6.18The integration of external software into a GIS via a RDBMS
6.19A portion of a print out from the IMAGE module of IDRISI
6.20An example of GIMMS output showing some population statistics for Jamaica
6.21Multi-tasking centralized engineering workstation
6.22Centralized configuration using a local area network
6.23Multiple processors and peripheral devices on a distributed network
7.1SPOT image showing shrimp ponds near Guayaquil, Ecuador
7.2SPOT image showing preselection sites for aquaculture in part of New Caledonia
7.3Enlargement of a SPOT image showing the Bouches du Diahot area of New Caledonia in detail
7.4RS image interpretation and analysis processes
7.5Base map of Etolin Island showing selected oyster sites and turbidity zones
7.6Bathymetry of Stikine Strait area looking S.W.
7.7Sequence of NOAA infrared satellite images showing development of an algal bloom over the Skagerrak in 1988
7.8Area of N.E. Zimbabwe covered by Landsat thematic mapper image
7.9Map of the dynamics of the water areas of Sarykamysh Lake
7.10Development areas and bathymetry around Long Point Bay, Lake Erie
7.11Density sliced image, black and white image and interpretation of sediment plumes in Long Point Bay for July 6, 1974
7.12Maps of Franklin parish, Louisiana, showing suitability for catfish farms
7.13Areas of suitability for trout farms, by 10 km2 cells
7.14Scored cells showing suitability for carp culture in Pakistan
7.15Graphic representation of cell scores showing suitability for carp culture in Pakistan
7.16Map produced by the GIS showing main soils and roads in S.E. Johor state
7.17GIS approach used for the site assessment showing the layers and constraints used
7.18Map showing suitable depths for salmonid cage culture in Camas Bruaich Bay, Scotland
7.19Soil suitability for pond development in Ghana
7.20Map showing distribution of fish farming potential in Ghana according to criteria for Integrated Model K2
7.21Fishery dependence of villagers in coastal settlements in southern Johore
7.22Educational attainment by distance from main towns and roads in southern Johore
7.23The geographic distribution of the northern Gulf Brown Shrimp population
7.24Algorithm for computing effects of dispersed or untreated oil on the Brown Shrimp stock and its associated fishery
7.25Plots showing the distribution of threatened or endangered fish and mussel species in Virginia
7.26Plot of the Clinch River basin showing relationship between active coal mines and streams having threatened or endangered species
7.27Location map of the Lake Marion study area
7.28Data sets in the Lake Marion GIS data base
7.29Herbicide spray locations in upper Lake Marion, 1982–85