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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXX V, Part B7. Istanbul 2004 
  
What do sustainability 
studies do: 
   
   
   
     
Best 
they address: BS! case 
e growth limiting 
e yield reducing 
e land modifying 
aspects of LUSs. 
we study 
ES this gap 
Worst case / 3 
Yield or Impact 
  
  
— They relate differences 
In land and manage- 
ment aspects to diffe- 
rences in system 
performances. 
— They use survey data 
from many plots 
  
  
  
AL 
  
Figure 1. What do sustainability studies do? 
Programmes or projects that address the stated sustainability 
issues specifically require timely and reliable (spatial) informa- 
tion on the productivity and sustainability of current agricul- 
tural land use systems. However, there is a general paucity of 
land use information in many developing countries and it is 
often difficult for the range of potential clients to access the 
information that is available. Young (1998) refers to the de- 
scribed vacuum as (see also George and Nachtergaele, 2002): 
e "to an extent which, viewed in retrospect, is remarkable, 
methods for the collection and analysis of land use data 
have lagged behind those for natural resource surveys", 
and 
* — "...the situation with respect to land use classification was 
comparable with that for soils in about 1950: a large num- 
ber of systems devised for national use, with no guidelines 
for comparison", 
whilst: 
"at national level, many countries are now seeking to 
monitor land use change as a basis for policy guidelines 
and action", and *...land use is generally treated as the 
second most fundamental set of statistics, following popu- 
lation". 
In short, we need good land use data to address questions as put 
on record by the UNCED conference in Rio (1992; Agenda 21, 
Chapter 10), e.g.: 
* to identify options to solve future food requirements. 
« .tounderstand and combat environmental degradation. 
and, we need practical concepts and approaches to: 
e gather, manage, classify and map land use informa- 
tion. 
e study various aspects of present day land use systems. 
2. OBJECTIVES 
Noting: 
e the complexity (and back-log) of capturing and managing 
required land use information, 
® the shortcoming to review the extent, variability, and qual- 
ity of existing land use data, 
e the requirements that proper geo-referenced products must 
become available in abundance, and 
* that further reviews of various existing land use concepts 
lead to further delays in producing the required products, 
the aim of this paper is to contribute to the development of 
compilation methods of spatial and temporal land-use data sets 
using existing data sources and improved GIS-based survey 
1149 
methods to subsequently make them available to the public 
with the help of recently developed data-dissemination tools. 
It is envisaged that, among others, collected data can be used 
for enhancing a broad range of studies in areas such as early 
warning in relation to food security, yield gap analysis studies, 
regional to global assessment studies, land-use planning, disas- 
ter mitigation, urban-rural linkages, the monitoring and assess- 
ment of land/water degradation, loss of biodiversity and ecosys- 
tem functions, as well as for project formulation. 
Topics covered are: 
* . Information technology for sustainable land management 
« Geomatics 
* Quality of present day land use information systems 
* Land use information system concepts 
e Use of RS for land use mapping 
e Land use survey aspects 
e Land use classification concepts 
e Classifiers 
e — A-priori versus a-posteriori land use classification 
e Harmonizing classifiers 
3. INFORMATION TECHNOLOGY FOR 
SUSTAINABLE LAND MANAGEMENT 
Geomatics 
In the early nineties, a ‘think-tank’ of the Atlantic Institute, 
representing faculties from NE-USA and E-Canada, came to 
the conclusion that (Beek and Groot, 1994): 
* Trends in land management studies are towards geomatics, 
defined by the Atlantic Institute as “the scientific man- 
agement of spatial information”. Boundaries between for- 
merly separate disciplines have become increasingly 
fuzzy; 
* Developments have moved from a period of innovation 
(1960-1980: technology driven, little data) through a pe- 
riod of integration (1975-2000: building databases) to a 
period of proliferation (1990 -: systems integration, mass 
dissemination, information customer driven). 
Information technology (IT) facilitates integration of informa- 
tion processing. This is obvious from the advent of manage- 
ment decision support systems that grew out of the manage- 
ment information systems. Geographic Information Systems 
(GIS) are a direct result of this integration. GIS provide the user 
community with tools that are unprecedented in their potential 
and challenge existing facilities. IT also has the capability to 
transform a data set at relatively low cost into new information 
products for specific users. An important consequence of these 
integration and customization characteristics of IT is that com- 
bined processing of data sets can deliver new information prod- 
ucts with an added value over the source data sets. IT has par- 
ticular significance for interdisciplinary land use planning. It 
facilitated decentralization of governance and progress in 
communication, it spurred research into sustainable use of natu- 
ral resources, and it opened international markets for technol- 
ogy and knowledge. 
Quality of present day land use information systems 
Stakeholders report that the effective use of GIS technology is 
constrained by the limited adequacy of data on land use systems 
(Table 1). The constraints were recorded at selected (sub-) 
national institutes in a number of developing countries (Dalal-