Landform Stability

Landform Stability

Landform Stability and Evolution

The main objectives of mine rehabilitation and reclamation is to create a safe, stable, non-polluting and self-sustaining landscape. But newly formed landscapes are often not in equilibrium with the environmental conditions in which they have been created. Responses to a state of non-equilibrium may be high reactivity and drastic changes in the physical, mechanical, chemical and biological state of the created landform. And the further the landform is from a state of equilibrium, the more intensive the processes will be. The processes affecting landform stability are across multiple environmental disciplines, such as hydrology, geochemistry, geomechanics and plant sciences. In order to achieve physical, mechanical, chemical and biological stability, the various functions of these processes need to be well understood.
For the abiotic components of a landform, responses to an unstable state can lead to severe consequences, like erosion, consolidation and high intensity chemical reactions. These can also affect the biological elements of a landscape, such as soil materials and vegetation cover, since the various biotic and abiotic processes are often very closely linked.

An understanding of the consequences of such responses can inform the design of stable landforms and their elements, such as soils and cover materials. Similarly, ongoing impacts leading to changes in the stability of a landform (e.g. subsidence), can be addressed by investigating the change in the landforms’ equilibrium with the environment.

The further the landform is from a state of equilibrium, the more intensive the processes will be

Current CMLR research in landform stability includes the optimisation of cover design under various climatic conditions for mine closure planning. Ecohydrological concepts for revegetation are built-in to improve the level of certainty for the successful establishment of the desired vegetation community. Hydrogeochemical parameters, from leaching tests in the laboratory, allow the creation of trajectories of the long-term behaviour of the materials under investigation. This work is closely linked to Environmental Geochemistry and Soil-Plant Systems research. In addition, advanced monitoring technologies utilised by CMLR enable the quantification of these landform processes in space and time.