Biodiversity loss has been identified as the environmental impact where humankind has been trespassing planetary boundaries most ruthlessly (followed by swelling the nitrogen cycle and climate change - both are main drivers of biodiversity loss). Going beyond the pressures causing damages and analysing their underlying driving forces, a series of drivers can be identified. Systematising them, land use (intensity), material (and substance) flows and energy consumption can be considered key categories, with land use intensity the most important factor. However, they are closely interconnected – for instance, energy consumption based on fuel flows enables additional material flows in agriculture (inputs, mechanisation) contributing to intensification. While aggregate energy flows in ecosystems can be characterised by Net Primary Production NPP and its Human Appropriation HANPP, and substance flows by material flow analysis, no such measure is available yet for land use intensity. Furthermore, statistics for individual components of land use intensity are often lacking, incomplete, with insufficient time series, in particular in developing countries, or are inconsistent. In such cases stakeholder interviews provide a means of identifying land use history as a basis for sustainable land use planning. In particular in countries with relatively weak statistical systems, oral information transfer often plays a high role and is of surprising quality. However, as stakeholders observe rather than measure change, classifying observations requires an ordinal scale approach, with classes wide enough to accommodate the observations but still suitable to characterise land use history. We suggest LUI, a new land use intensity index characterising changes in land use intensity over time, to be used in such cases; such an index does not exist so far (thus this is a conceptual proposal for an index to be tested empirically, with no experimental data available so far). It would be a valuable source of information regarding the dominant driver of biodiversity loss. For the qualitative aspect of ecosystem fragmentation, it can be integrated with the EU’s habitat fragmentation index. Combining the fragmentation index and LUI based on the same data sets would allow for a comprehensive assessment of land use intensity; it could also be used for monitoring if land use intensity is indeed reduced. Its simple and intuitively understandable structure makes it suitable for citizens’ science applications, and thus for participative monitoring when extensive statistical data gathering is not feasible.
Key words
Biodiversity loss, driving forces, land use intensity, fragmentation, Land Use Intensity index LUI
