International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004
Clayton and Dent, 1993) and in four European countries (Zeijl-
Rozema ef al., 1997).
The recorded statements on present day land use system infor-
mation for natural resource management and planning called
for (guidelines on) data harmonization. Aspects to be consid-
ered are listed in Table 2.
Table 1. Constraints regarding effective use of land use
system information as reported by stakeholders
Data Aspect Problem Frequency
Availability : what is where? Occurs
(supply defined?) unobtainable, restricted Often
limited coverage Regular
Format : supplier defined Often
data integration problems Often
different parcel registries Regular
Quality : lack of uniformity Often
no accuracy assessments Regular
Documentation: often incomplete Occurs
poor nomenclature Often
Geo-referencing : | sometimes absent Occurs
Costs : . Often expensive Regular
Updates : poor update frequency Regular
no time series Occurs
Coordination : end users not involved Often
poor between organizations Often
no regulations Occurs
Classification : not tailored to user needs Often
no user consultations Often
lack of uniformity Constant
limited utility Constant
Table 2. Data aspects that need attention if the quality of pre-
sent day land use system information is to be improved
Data Aspect Problem
Concepts differentiate between
land use and land cover
survey methodologies
observation units
Data accuracy and consistency
Scale and legend correctness,
Type of data classes vs. numeric in-
formation
Class definitions user consultations
Definitions nomenclature
Consistency for time-series replicability
Data formats relational database, GIS
formats
Documentation set regulations
Land use information system concepts
At present, digital databases are being developed that form a
part of the information infrastructure required for sustainable
land management at various scales. The development of GIS
has dramatically increased the demand for reliable geo-.
referenced data at all levels of detail.
UN organizations supported by specialized institutes develop
standards and software for the collection and analysis of geo-
referenced information on climate, soil and terrain conditions,
water resources, land use, land cover and bio-diversity, and on
social and economic conditions. All of these must be referenced
with up-to-date and accurate topographic and cadastral
information. (Inter-) national programs are needed to unite such
databases in a uniform geo-information infrastructure. Exam-
ples of initiatives are GSDI (Global Spatial Data Infrastruc-
ture), EUROGI and Eurostat (Europe), and RAVI (The Nether-
lands). The Open GIS Consortium is a similar initiative on a
world scale that was started by US-based Gl-industries.
Figure 2 provides a basic "root structure" (concept) of a com-
prehensive land use systems (LUS) information system. Given
that it was developed from the conceptual LUS-diagram pro-
vided in Figure 3, the part on land use is elaborated in further
detail.
Figure 3 shows that a land use system is composed of two main
elements: land and land use. A Land Use System (LUS) was
defined by De Bie (2000) as: "A specific land use, practiced
during a known period of time on a known unit of land that is
considered homogeneous in land resources"; Land Use was
defined as: "A series of operations on land, carried out by hu-
mans, with the intention to obtain products and/or benefits
through using land resources". Land use purpose(s), i.e. the
intended products or benefits of land use, and an operation se-
quence, i.e. a series of operations on land in order to realize one
or more set land use purposes, characterize land use. Note that
land use systems have both spatial and temporal dimensions.
These must be understood if one endeavors to describe, clas-
sify, survey or study land use systems at the level of spatial
aggregation required for solving specific natural resources
management problems.
For the land use part, Figure 4 suggests two sets of relational
database files as required to capture land use descriptions. The
first set is called “Actual Land Use System Data" and contains
collected land use information, either primary or secondary.
The second is called “Defined A-priori Classification Systems”
and contains information on a-priori land use classes, i.e. class
names and classifiers used to define the classes. Parameter val-
ues used in each set are derived form a *Glossary". The data-
base files are all linked through index-keys; relevant links are
presented in Figure 4. The various data files are:
e Data set identifications: Contains general information
that identifies a particular data set, including the adminis-
trative area; project under which the survey takes place,
names of enumerator and respondent, holder, etc.
e Site Identifications: Contains data that provide detailed
information about the geographic location of the site(s)
under study such as map unit, cadastral no., parcel size etc.
e Land Use System Descriptions: Contains general infor-
mation about the land use system such as plot location and
size, operations seq. duration, a-priori land use class, etc.
e Operations and Observations: Contains data on individ-
ual operations and observations.
e Land Use Classes: Contains information on a-priori land
use classes. A land use class is defined without any tempo-
ral and spatial dimensions. It is a universally applicable
land use description based on well-defined classifiers.
To understand the “operation sequence” better, some defini-
tions follow:
Operations (Figure 5) are intended to modify land aspects, e.g.
soil characteristics or land cover. Some modifications are per-
manent (constructing infrastructure) whereas others can be of a
temporary nature, e.g. the successive land cover types ‘bare
soil, crop, and stubble’ are brought about by ‘ploughing, plant-
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