Within the past decade, there has been a virtual explosion of modelling activities attempting to predict the consequences of global change on ecosystem structure and function. These projects have ranged in scale from continental to global assessments of contemporary and future terrestrial carbon stocks. While such activities have been rigorously defined in terms of model input and output variables, vegetation structure drivers have assumed potential vegetation and ecosystem equilibrium. It has become clear that the fiction inherent in these assumptions could lead the global-change community into unrealistic predictions of carbon flux. An organised database providing land-use and land-cover changes over the past 300 years is crucial to future modelling scenarios regarding the impacts and consequences of global change on terrestrial ecosystems.
The charge of the Land Use Cover/Change core project (LUCC) is to develop case studies at the local and regional scale which focus on understanding the socio-economic and environmental drivers of land-use change and to incorporate those in comprehensive integrated models. While the Land Use Cover/Change (LUCC) core project is currently embarking on developing a historic land-use and land-cover database, this database is not yet currently available or foreseen to be available in the coming years. Further, the LUCC endeavour may not include all the specific land-cover information required for global carbon and vegetation modelling, such as forest removal rates, harvest dates, and the subsequent successional dynamics. Such strong land-cover focus would be criticised by the LUCC community for not including human societal drivers, but this is somewhat less relevant to GAIM in terms of global modelling.
Therefore a rapid development of a fast-track historic land-use and land cover database will be initiated from GAIM in close collaboration with other core projects. This initiative will start from existing studies and databases and develop approaches to estimate and fill in gaps. Available regional land-use databases include those from Richards in S.E. Asia, Ariel Lugo in Amazonia and Sandra Brown in the US. In addition, some global databases have already been compiled. For example, a global 100 yr. crop database has been developed by Ramakutty Navin at the University of Wisconsin and a historic land-use and land-cover database (HYDE) by the IMAGE team at RIVM.
There is an inherent conflict in this activity: The scientific community would like to see a geographic-specific database to build on ongoing activities, whereas people who build the maps don't necessarily understand the biogeochemical consequences of the change: e.g. regrowth or new plant functional types. The key, therefore, is to develop an appropriate database that provides information on the land use /land cover changes over time (the past) and their biogeochemical consequences. The flow of understanding runs in two directions. If the biogeochemical consequences of land cover can be translated into human societal impacts, both the scientific and human dimension communities can profit enormously from a joint collaboration.
The objective of a fast-track historic land-use and land-cover database project is to develop an intersection between GCTE, LUCC, PAGES, and GAIM to identify: (1) existing (regional) databases that may be utilised; (2) key missing components in space and time; and (3) a methodology and appropriate team to translate existing databases from LUCC and other Core Projects to a suitable format for the global modelling community. To this end, a working group is proposed to be held in late 1999 in The Netherlands to develop a workshop that would pull together existing regional and global databases.
Late 1999: working group consisting of members from LUCC, GCTE, PAGES, GAIM, and others (e.g. Jonathon Foley, Sandra Brown, Ariel Lugo, Richards, Elaine Matthews, Ruth DeFries, Marie-Jose Gaillard-Lemdahl, and others) to outline a workshop that would formulate an appropriate methodology for identifying existing databases and identify missing land use/land cover components. Objectives would include the identification of: (1) a minimum criteria for the spatial and temporal resolution of the land use/land cover database; (2) minimum land use/land cover types to be considered in a global database; (3) current existing regional and global databases; and (4) identify missing regions/time slices over the past 300 years. .
Mid 2000: Workshop to develop translation and assembly rules for existing land cover/land use databases.
1. Immediate needs include funds to host the initial working group and workshop. 2. In addition, there will be a need to cover the salary of a technician or post-doc who can be responsible for the ultimate assembly and maintenance of the databases. 3. There will be a need for a data server and location where the databases can be housed online.