Ministry of Environment

Sensitive Ecosystems InventoriesSensitive Ecosystems Inventories

Central Okanagan Methodology

Methods

The Central Okanagan Sensitive Ecosystems Inventory used the provincially recognized Terrestrial Ecosystem Mapping (TEM) approach to develop a base map. TEM units were then evaluated for rarity and ecological sensitivity and were assigned to 'sensitive ecosystems' and 'other important ecosystems' categories accordingly. Criteria for ecological sensitivity included the presence of shallow soils, the susceptibility of the site to hydrological changes, erosion, and invasion by noxious weeds, and sensitivity associated with human disturbance.

A detailed description of the methodology used can be found in the Technical Report.

The methods used for this project combined the rigorous inventory work done in the South Okanagan and the user-friendly methods used in the Sensitive Ecosystem Inventory projects on Vancouver Island and the Sunshine Coast. The Terrestrial Ecosystem Mapping (TEM) approach used in this project provides a base map consistent with work done in the South Okanagan, enabling Okanagan-wide analysis and aiding in the development of an Okanagan-wide conservation strategy.

Limitations of the Methods

The SEI and TEM information is intended for use in alerting local and regional decision-makers of the presence of important ecosystems and ecological features. This mapping does not replace the need for on-site assessments of areas where land use changes are proposed or contemplated.

Scale: The accuracy of polygon boundaries is limited by the scale (1:15,000) and date (1994 and 1996) of the aerial photographs on which the sites are delineated. Data should not be enlarged beyond the scale of the photos as this may result in unacceptable distortion and faulty registration with other data sets.

Accuracy: Given the continuing land-uses within the Central Okanagan including development and logging, some polygons may have changed since the data of the aerial photographs and/or fieldwork.

Aerial photograph interpretations provide only limited ability to see specific disturbances such as grazing and invasion of noxious weeds. Some grasslands may be incorrectly assigned to either 'grasslands' or 'disturbed grasslands.'

Size and complexity of polygons: In most cases, small sensitive features or ecosystems are captured as a small component of a larger polygon dominated by another ecosystem. Many polygons are a complex of ecosystem types and sensitive ecosystems may only occupy a portion of that polygon.

For more information on mapping limitations see the Technical Report.

Habitat Conservation Trust Fund, Regional District of Central Okanagan, British Columbia, Environment Canada