Spatial & temporal scales

Importance of different spatial & temporal scales of rivers

Effective river restoration requires a better understanding of how rivers work and interact on many temporal and spatial scales.

What are the spatial and temporal scales used in restoration studies?

Commonly used spatial and temporal scales in describing rivers and their catchments.

Commonly used spatial and temporal scales in describing rivers and their catchments.

What is the importance of different SPATIAL scales?
The planning, design, and implementation of river restoration (levee removal, channel engineering, planting riparian vegetation, etc.) necessarily occur at the scale of reaches and sub-reaches. However, local restoration projects are most effective if they are designed using a catchment scale, which will bring greater ecological benefit.

Catchment scale provides a larger frame of reference for smaller scale projects, which allows for understanding how valley form, how river network structure and natural disturbances (floods, fires, landsliding) affect restoration projects, positively or negatively. That is, the river reaches depends not only upon natural processes and human interventions within the reach or sub reach scales, but also within of the catchment scale.

And, what is the importance of different TEMPORAL scales?
Responses of river reaches to changes in processes and human pressures across the catchment is often delayed. This is because it takes time for the effects of changes (e.g., land cover change, dam construction) to propagate from their initial location across catchments and through river networks to river reaches and sub-reaches. Thus, understanding rivers ecosystems requires knowledge of processes and human pressures at different temporal scales also.

Without such a spatial and temporal understanding, management interventions cannot be fully informed and so, they may not be sustainable and may potentially require significant ongoing maintenance

The integration of spatial characteristics and their changes through time allows the investigators to identify which spatial units and temporal scales drives the geomorphic and hydrological forms and the ecological processes in catchments. This is the basis for diagnosing the causes and effects to support planning and implementation of local projects of river restoration.

 /Aneliza Melo