An obvious conclusion of this study is that systematic global studies of land use areas are missing and that existing datasets are not sufficient to provide a detailed view of land use dynamics. For specific fields, like forestry or urban areas, knowledge seems to be adequate, although underlying data in these studies are also weak. Given the considerable attention that the environment, rural poverty and food security has enjoyed over past decades in a proliferation of international arrangements, it must be concluded that these arrangements have neither facilitated effective global monitoring and assessment, nor based their decisions related to land use dynamics on verified knowledge – as such knowledge does not exist.
On the specific findings in this paper, it is obvious that several aspects of land use dynamics are not well covered:
- Within-category changes are significant but are not visible in this presentation. For example forest degradation and desertification are processes of major concern that not necessarily leads to transitions betwene land use ctaegories, but that significantly affect productivity and environmental functions of the land and resources. Similarly, the intensification of agriculture has major impacts on agricultural outputs and the environment, but is not shown in a simpolified matrix like this.
- Smaller-size ecosystems, such as mangroves, wetlands of different kinds, specific forest types, some mountain areas, etc., are often severly affected by land use. However, due to relatively small extent, these impacts will not show up in this type of global change matrix.
On data quality, the study has used state-of-the-art statistics of global land use. Nevertheless, it is clear that major discrepancies may still be present. For example, an independent systematic study in FRA 2000 (FAO 2001) showed that the deforestation rate in Africa may be overestimated by more than a factor 2.