The concept of using a demonstration project that all participating networks could find useful and at the same time serve a useful purpose for GCOS and GTOS was introduced by Dr Cihlar. He presented two potential candidates (soil carbon and global forest cover). Dr Cihlar stated in principle a demonstration project should serve several objectives: demonstrate the effectiveness of a Global Observing System Network (GOS-Net) by generating important global data sets which could not be produced otherwise; provide a test bed for the development of mechanisms for the collaboration among networks and sites, including issues of coordination, data sharing and exchange, etc.; and obtain the experience needed for a further development of the global terrestrial network. He noted at the beginning of his presentation that the two particular projects may or may not be appropriate as initial demonstration projects, but was presenting them for two purposes: 1) to give the networks information on other ongoing activities, and 2) to get participants to begin to think about an appropriate project that could be undertaken.
A project to characterise soil carbon was originally identified as a candidate project at the In Situ Observations for the Global Observing Systems meeting held in Geneva in September 1996. The rationale behind the proposal was that soil carbon plays a key role in maintaining soil structure and productivity and is also one of the largest pools in the global carbon cycle. A pre-proposal has been prepared by the TOPC and circulated for comments. The goal of the project would be to produce a global data set for the distribution of the total soil carbon and its associated variables to:
Understand and quantify the role of soil carbon in the global carbon cycle and climate change;
Assess the present state of soil quality and future changes.
The comments received to date are wide-ranging from ‘it is too ambitious’ to ‘this data set is one of the most valuable that could be produced’. Dr Cihlar pointed out that the precise characterisation of carbon in various pools is not feasible at the global scale without much time and financial resources. Hence such a project, while potentially very useful, would be extremely difficult to complete in a relatively short period of time and in a highly accurate manner.
The discussion which followed confirmed that at present such a project was probably not a suitable candidate for an initial collaborative effort and that it should be considered once GTOS is further developed and sources of funding can be found.
The Committee on Earth Observation Satellites (CEOS) has proposed several projects to obtain practical experience in implementing global monitoring based on the integration of satellite and in situ observations. One proposed project is to develop a database of forest cover. The tentative objectives of this proposal are:
To provide a database of systematic, complete and reliable earth observation data with ground resolution in the order of tens of meters, from which information about forest cover and its changes can be derived;
To foster a close collaboration between the data providers and users in order to encourage and facilitate an effective use of the database, including easy and rapid access;
To provide a repository for forest cover information which can be accessed by a wide spectrum of users.
Dr Cihlar pointed out that this project was under development by CEOS, with a key workshop scheduled for July 1997. Nevertheless, he felt that the project presented an opportunity for the networks to become involved. Many of the networks indicated an interest in staying involved with this project as it was further developed. However, some networks from semi-arid regions were uncertain as to the relevance of the project, pointing out that the extent of geographic coverage and the definition of ‘forest’ would be important in their potential participation. The project would also be of limited interest to networks concerned with agroecosystems. While it was decided not to pursue this project further at the meeting it was agreed that the project could meet the demonstration project objectives if the focus were on the forest ecosystems and networks. It was also agreed that additional networks should become involved, according to their interests.
To provide participants with another potential activity on which a demonstration project could be built. Prof. David Norse described the Coordinating Land Use and Cover Data and Analyses in Europe (CLAUDE) project. The overall objective of the project is to develop an internally consistent, Europe-wide plan for land use and land cover monitoring and research, and to link with other international programmes on this issue. The project will evaluate land use and land cover (LUC) data collection methods and data base structures as currently developed and used in several countries of the European Union (EU) in relation to environmental management and policy formulation needs. This will allow the assessment and monitoring of land use and cover changes, including ecosystem process changes, at different scales as a major input into a future joint approach to LUC in the EU. He felt that the data base structures and metadata that are developed in this project could be very useful to GTOS.
It was agreed that the GOS-Net should undertake a project which will demonstrate the potential of an initial network of sites to generate a reliable, useful product with global coverage and regional or local relevance, rapidly and efficiently, by adopting the hierarchical approach and using models to combine in situ and remotely sensed data. The participants concluded a set of output products, which have Net Primary Productivity (NPP) as their common foundation would serve this purpose, and is achievable within the desired time frame by collaboration with existing initiatives. The project is designed so that any network or site regardless of its level of sophistication can make a useful contribution.
Net Primary Production (NPP), which is the amount of new plant growth, which occurs within a given area over a specified time period (g m-2 y-1) is a key integrator of ecosystem function. It is the mechanistic basis of harvest yield, whether it be of edible plant products, timber or meat. Deviation of NPP from its expected value is an objective indicator of ecosystem degradation, which is of direct use to the Convention on Desertification. Net Ecosystem Production (NEP) is a related variable derived from NPP which is of crucial importance in the global carbon cycle, and thus to the Framework Convention on Climate Change.
The calculation of NPP requires the collection of a set of input data which are valuable long-term observations in their own right: rainfall, temperature, soil water holding capacity and nitrogen content, land cover and Leaf Area Index (LAI). Land cover is of direct relevance to the Biodiversity Convention and Climate Change Convention; water holding capacity and nitrogen content of soils are measures of degradation, and nitrogen content correlates closely with soil carbon, of interest in the global carbon cycle. It was mentioned that a similar project was underway in the United States, and that information on that project was available on the Internet (http://atlantic.evsc.virginia.edu/jhp7e/modlers). The NPP/NEP focus thus meets most of the requirements of a demonstration project. (See Annex IV for a preliminary draft of the proposal.)
