Land Degradation in Drylands: Reëvaluating Pattern-Process Interrelationships and the Role of Ecogeomorphology

Abstract

In this book we have argued that improved understanding of land degradation in drylands needs a problem-centred multidisciplinary approach. Specifically, we have argued for an ecogeomorphic approach. In this concluding chapter we review successes and shortcomings of this approach, identify key challenges that need to be overcome, and present the conceptual and methodological advances that need to be made to overcome these challenges. There has been a wealth of research investigating patterns and processes separately at small spatial scales, and, some advances in linking ecology and geomorphology have been made. However, there remains little in the way of true integration across the disciplines that deal with both ecogeomorphic patterns and processes. To overcome this weakness, it is imperative that the lessons of ecology are learned – to value truly coupled eco-hydro-geomorphic studies, in which biogeochemistry, plants, geomorphology, soils and hydrology are all well represented and experimentally manipulated – and that the lessons of geomorphology and hydrology are learned: to value observational studies in which ecological measurements are coupled with hydrological and geomorphological measurements, and the role of exogenous forces is explicitly recognized. No one approach will be applicable to understanding land degradation in drylands. Unique settings, both biophysical and cultural, mean that the solutions to land degradation differ from place to place. Furthermore, evolutionary changes in drylands – degraded or otherwise – mean that methodological approaches employed to study the system may need to be fluid. We conclude the chapter by identifying five key challenges for land-degradation studies in drylands. First, a common language needs to be developed. Secondly, the problem of scale and scale interactions needs to be overcome. Thirdly, the lessons of complexity science need to be accepted and acted upon. Fourthly, the understanding of the interactions of ecogeomorphic processes and people needs to be improved. Fifthly, management strategies for combatting land degradation in drylands need to be developed taking account of scientific advances, but not waiting for an “ultimate solution” that will never arrive.