Hydrology

Select from the tabs below

• Overview
• Region
• Catchment and subcatchment
• Aggregation/Super reach
• Land unit and subunit
• Patch/Micropatch

Hydrology is important for understanding the landscape and the ecosystems within it. Hydrology influences landscapes and ecosystems and is itself influenced by the ecosystems. Variable water flows, water levels and connections (known as water regime) affect the biological and chemical processes in an ecosystem. Hydrology is different from hydraulics.

How water moves in the landscape is influenced by a range of factors including:

• climate – rainfall (and other precipitation), temperature, evaporation
• physical characteristics – geology, soils, topography, catchment size and shape, modifications (such as dams, weirs or levees)
• biological features - vegetation cover, transpiration
• prior conditions – soil moisture and groundwater levels.

Scale

Hydrology is impacted in a different manner by the landscape and ecosystems at different scales. In order to properly manage a catchment or particular part of the landscape (land unit) it is vital to understand how water moves in the broader landscape/ catchment. Various methods are available to assist in understanding the hydrology of a catchment or subcatchment. These include hydrological modelling and the ‘walking the landscape’ process.

Region

A region is an area that experiences similar rainfall, temperatures and weather patterns (e.g. wet tropics).

Catchment (Subregion)

Larger catchments are made up of smaller subcatchments, which form tributaries to the main watercourse within the catchment. The degree to which the overall catchment affects a smaller subcatchment depends on the degree of connection, through features such as floodplains, where parts of the subcatchment are inundated, during a flood event or through groundwater flows or stream flows.  A catchments hydrology is influenced by the region in which it is located.

Subcatchment (Landscape)

A subcatchment's rainfall, topography and geology are the main influences on the water regime of a subcatchment, including the duration and timing of local runoff, channel inflows, flooding, precipitation and groundwater flows from the broader landscape.

Land unit (Habitat)

Some land units will have very simple hydrology, e.g. upland rainforest receives rainfall and lose water by evapotranspiration, infiltration or runoff. Others, such as wetlands, lower in the landscape, will have complex interactions of local and catchment runoff, groundwater flows, infiltration and evapotranspiration.

Subunit (Community/Site)

A subunit is part of a land unit which may be different than other parts of a land unit, for example, a particular plant community, or flow paths within a wetland.

Additional Information

• The Queensland Water Modelling Network (QWMN) page includes a strategic review of models suite with documents on an assessment framework and model classification.

Pages under this section

References

1. ^ Department of Environment and Conservation (2012), A guide to managing and restoring wetlands in Western Australia. [online], Department of Environment and Conservation, Perth. Available at: https://www.dpaw.wa.gov.au/management/wetlands/publications-and-links/218-a-guide-to-managing-and-restoring-wetlands-in-western-australia.

Last updated: 28 September 2021