Professor Sabine Grunwald,   University of Florida.

Professor Sabine Grunwald, University of Florida.

‘Pedo’ and ‘metrics’ emphasize two perspectives, where the former highlights pedological knowledge and the latter the methodology and computational tools used to understand the past, current, future conditions and change of soils. This understanding of pedology and physico-, biological- and chemical transformations has been transposed into sophisticated maps and models. The main focus in this talk is on the “Why” and “How” soils develop, degrade, improve or are sustained in terms of their performance to meet needs (e.g., crop yield in context of food security), functions (e.g., soil carbon sequestration), values and benefits (e.g., water holding capacity), conditions (e.g., various soil properties) or overall perceptions (soil health, quality, and security). Since the invocation of pedometrics we have seen shifts in how physical, chemical, and biological process knowledge has been incorporated in soil models. An increased understanding of relationships between environmental factors and soil properties as well as biogeochemical cycles derived from empirical measurements (e.g. vadose zone) have afforded to improve our body of knowledge. Trends to couple these soil models explicitly with the human and life dimensions are underway to move from simpler model representations (e.g., incorporation of land use) to models that explicitly account for human actions, values, beliefs, decisions, and other organisms (e.g., microbial processes) allowing improved back- and forecasting (e.g., global climate change) and evaluation of scenarios (e.g., adaptation in soil management).  Improved soil-environmental data availability through remote and proximal sensing technologies combined with advancements in computational ability have afforded to build ever better soil factorial models rooted in empirical science.  Specialized process-based soil models to simulate soil change (quasi)mechanistically have been used in standalone mode or embedded in holistic Earth System Simulation Models and ecosystem models. Trends and issues related to how we transpose what we know about soils at a point (site) to spatial and temporal model scales and associated uncertainties will be addressed. I will also discuss the mainstream paradigms in pedometrics rooted in empiricism and reductionism (i.e., deduct data and process-knowledge at finer and finer scales and build more detailed and complex models) in light of the needs to synthesize soil knowledge to resolve the global grand challenges and crises of our time.