Stream bank vegetation
Why we monitor stream bank vegetation
The demands on the region’s rivers and streams continue to increase as the result of land use intensification. The long-term management of these resources is a high priority to ensure fresh water quality and aquatic biodiversity within the Waikato region are preserved for future generations. Riparian management techniques such as fencing and planting of riparian zones are an effective way of improving water quality and increasing aquatic and terrestrial biodiversity.
Waikato Regional Council monitors stream bank vegetation to quantify what proportion of the region’s riparian margins requires further stream bank vegetation planting.
The regional riparian characteristics survey provides a repeatable and quantitative assessment of riparian fencing, vegetation, and stream bank erosion through pastoral land in the Waikato region. In addition to supporting catchment management zone works the survey information potentially supports our biodiversity, biosecurity, and environmental education strategies and programmes.
The survey provides a benchmark on stream bank vegetation and, through ongoing monitoring, can provide a gauge of the effectiveness of Waikato Regional Council’s riparian policies.
Riparian vegetation has been surveyed along 1km lengths of waterways. The vegetation has been classified into woody and non-woody vegetation.
The stream bank vegetation indicator shows:
- The amount of woody vegetation (as a proportion of bank length fenced) across the region has not changed significantly over the 2002-2012 period (24% in 2002 and 26% in 2012).
- There has been a slight decrease in the amount of woody vegetation over the 2007-2012 period, from 31% in 2007 to 26% in 2012).
- The woody vegetation is predominantly comprised of woody exotic vegetation. However, the proportion of bank length with woody native vegetation has increased slightly from 6.6% in 2002 to 8.4% in 2012. The non-woody vegetation is predominantly comprised of pastoral grass cover.
- The predominant structure of the woody vegetation in 2007 and 2012 was described as ‘treeland’ – widely spaced trees (> 3 m in height) with grass in between them.
More detail on this indicator, including how and where the Waikato Regional Council collects this information, is available in the technical information page.
When this indicator is updated
The indicator is updated every five years.
Preparations for the next regional riparian characteristics survey, including any refinements to the survey method and design, will get underway in 2016/17. Data collection for the next survey is due to be undertaken during the summer/autumn period of 2017/18.
Contact at Waikato Regional Council
Land and Soil Scientist – Science and Strategy Directorate