Issue: Catchment scale influences - Land and vegetation condition - Vegetation
This is an issue under the Inland waters theme of the Data Reporting System.
The health of in-stream and riparian habitats is vital to the functioning of aquatic ecosystems, as well as to the terrestrial species that depend on the stream for water, food and various other contributions. Activities on the land and condition of terrestrial vegetation will impact on aquatic systems and activities affecting in-stream ecosystems will impact on riparian systems.
Vegetation cover and condition, terrestrial vegetation more broadly as well as wetland vegetation (see Issue: Response of biota - Wetland and floodplain communities ) and riparian vegetation (see Issue: Habitat scale influences - Riparian vegetation ), is also important to the hydrological balance of catchments. For instance, the replacement of deep-rooted perennial vegetation with shallow-rooted short-lived pastures and crops has caused water tables to rise. This has been the major cause of dryland salinity and water-logging. Rising saline watertables can, in turn, prevent vegetation of any kind from surviving (see Issue: Direct pressure of human activities on the land - Salinity ). Vegetation also protects soil from erosion. Erosion can have diverse impacts on inland waters (see Related issues, below).
- IW-26 Forested streamlength
Riparian vegetation protects waterbodies from pollutants by filtering catchment runoff, reduces bank erosion, provides instream and bank habitats and provides food for biota. The condition and extent of the vegetation will impact on its ability to carry out these functions.
Although the indicator does not provide insight into the extent or condition of riparian vegetation, forested streamlength does provide a direct and measurable indication of how much of the length of Australian streams are protected by streamside vegetation, the streams, where it continues to be lost, where revegetation is occurring, and the rate at which the loss or revegetation is occurring.
- IW-34 Examples of deterioration of condition of wetland vegetation
Wetland vegetation is a critical component of land and vegetation condition.
- LD-01 The proportion and area of native vegetation and changes over time
Native vegetation is a determinant of the condition of inland waters. Vegetation helps keep the water table low and protects surface waters by shading them from direct sunlight and holding banks together. Native vegetation cleared is an indicator for this pressure on inland waters.
- LD-03 Change in extent and proportion of woody vegetation, clearing and regrowth
Extent and change in extent, clearing and regrowth of woody vegetative cover is a surrogate indicator of the condition of vegetation.
- LD-17 Fragmentation of remnant vegetation
Fragmentation of vegetation, especially along inland water courses is compounds other pressures impacting on vegetation condition.
- Biodiversity - Pressures on biodiversity- Land clearing
- Biodiversity - Landscapes- Ecosystem diversity
- Biodiversity - Landscapes- Government action on landscape protection
- Land - Land condition- Hydrology
- Land - Direct pressure of human activities on the land- Land clearing
- Land - Contributions and pressures between the land and inland water- Pressures of changes to the land on inland waters
- Land - Contributions and pressures between the land and inland water- Pressures of changes to inland waters on land
- Inland Waters - Catchment scale influences- Land and vegetation condition- Vegetation
- Inland Waters - Habitat scale influences- Riparian vegetation
- Inland Waters - Response of biota- Wetland and floodplain communities
- Inland Waters - Human response - policy and management- Habitat management (including wetland management)
- Inland Waters - Habitat scale influences- Water Quality (for surface and groundwater)- Nutrients
- Inland Waters - Catchment scale influences- Land and vegetation condition- Erosion
- Inland Waters - Catchment scale influences- Land and vegetation condition- Nutrients and sediments - sources and loads
- Inland Waters - Habitat scale influences- In-stream habitat - woody debris and sand slugs
- Land - Direct pressure of human activities on the land- Salinity