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Research Report 221 A methodology for assessing the biodiversity of road networks: a New Zealand case study

Published: | Category: Environmental impacts of land transport , Research programme , Research & reports | Audience: General

The public road network makes an extensive and unique contribution to the public lands of New Zealand. It has a total area greater than our fifth largest national park, and connects and bisects New Zealand's towns and landscapes.

While the main purposes of road construction and management are transport efficiency and safety, significant benefit can be obtained by enhancing other aspects of the road reserve, such as its biodiversity or scenic values, and reducing the negative impacts of the road and roading activities on the surrounding areas.

This report, researched in 1999–2001, describes a methodology for characterising the biodiversity assets and liabilities of road networks using a combination of rigorous probability sampling, modern spatial analysis, and descriptive surveys.

Digital highway skeletons were developed of the Waikato Region (North Island, New Zealand) state highway network to depict important road attributes and environmental characteristics of roads and road reserves.

The methods for assessing roadside vegetation are demonstrated by focusing on biodiversity values and weed distributions, using new methods of field sampling and surveying.

Keywords: analysis, biodiversity, databases, environment, indigenous vegetation, introduced vegetation, native vegetation, New Zealand, probability, regression analysis, roads, sampling, spatial analysis, statistical analysis, vegetation, Waikato, weeds

Publication details

  • Author:
  • Published: 2002
  • Reference: 221