Landscape Function 

The biophysical processes that affect how landscapes function are inter-related and include the capture of energy, retention and use of water and cycling of nutrients.

The first of these is perhaps the most difficult to understand and is thus often underestimated. Our environment is forever being shaped by two sources of energy: the sun, and gravity compelling water and anything it can carry downhill. Without plants buffering these forces, these forms of energy would continually desiccate and erode our landscapes and waterways. Functional landscapes have a high capacity to buffer this energy.

Functional landscapes provide important biophysical and socioeconomic goods and services. Landscape functions include:  

  • Maintaining basic processes such as capturing and dissipating energy, retaining, using and cycling water and nutrients 

  • Providing habitats for biodiverse populations of plants, animals and micro-organisms 

  • Sustaining people by providing their material, cultural and spiritual needs 

On the other hand, dysfunctional landscapes have impaired capacities for one or more of these functions. Restoring a disturbed landscape means repairing its damaged functions. 

Landscape Resilience 

A functional landscape is a resilient landscape. A resilient landscape is one that can resist or bounce back after a shock such as a drought, flood, or fire. Landscapes are resilient when biological, physical and chemical processes are optimally contributing to the healthy cycling of water, carbon, and nutrients between the atmosphere and the landscape system. A landscape that lacks resilience is one that does not bounce back after a shock. It may be thrust into a downward spiral of accelerating degradation.

The following diagram presents an illustration of systems resilience. It was developed to communicate a “state and transition” approach that can monitor trajectories of change within an interconnected system comprising a complex of biophysical and social interactions (Image sourced from SECAP 2014, p. 33, see references below).

A short animation about solar energy

The analogy presented here is of a ball sitting within a desired condition state (A). The ball (A) is subjected to a shock and is pushed towards a different condition state (B). If the ball is resilient to shocks, it will settle back into a desired condition state (A) when the shock passes. If the ball is not resilient to shocks, it will be pushed towards a threshold (C). Condition states B and C are transitional states. Continued shocks could see the condition state of the ball transition beyond the threshold (D) and tip into a completely different, undesired, condition state (E). 

Some features of hydrated, functional landscapes include:

  • high levels of vegetative groundcover

  • healthy, water-receptive soils

  • clean surface water flows

  • stable stream forms

  • high levels of primary productivity.

Water moves through a functional, hydrated landscape more slowly. The volume stored in soils and vegetation is greater. Stream pulse events are moderated, reducing the erosive energy of flows and increasing the permanency of streams.

The human, social dimension of a landscape system carries the potential to maintain, recover and build healthy, functional, resilient landscapes. When individuals and communities have a solid understanding of key landscape processes, they are equipped to make transformational land management decisions for wide benefit. 

References:

Chapin, F.S, III, G.P. Kofinas, C. Folke (eds.), 2009, Principles of Ecosystem Stewardship: Resilience-Based Natural Resource Management in a Changing World. Springer Verlag, New York. See Chapter 1.

Peel, L., Hazell, P., Bernardi, T., Dovers, S., Freudenberger, D., Hall, C., Hazell, D., Jehne, W., Moore, L. and Nairn, G. (2022), The Mulloon Rehydration Initiative: The project’s establishment and monitoring framework. Ecol Manag Restor, 23: 25-42. https://doi.org/10.1111/emr.12549

South East Catchment Action Plan (2014) Local Land Services - South East, NSW Government. https://www.lls.nsw.gov.au/__data/assets/pdf_file/0009/752832/South-East-CAP.pdf

Tongway, D. J. and J. A. Ludwig (2011). Restoring disturbed landscapes: putting principles into practice, Island Press. 

Tongway, D. & Ludwig, J. (1996) ‘Rehabilitation of Semiarid Landscapes in Australia. I. Restoring Productive Soil Patches’ Restoration Ecology vol 4, no, 4, 388-397. 

Tongway, D. & N Hindley (2004). Landscape Function Analysis: Procedures for Monitoring and Assessing Landscapes. CSIRO, Canberra.