Innovation-March_April 2013

f ea t u r e s

appropriate practices on karst. Under FRPA, karst is legally recognized as a resource feature, and surface and sub- surface elements of karst systems must be protected when they are identified through Government Actions Regulation (GAR) Orders. The principal karst inventory and evaluation activity carried out for forestry at an operational scale is the Karst Field Assessment (KFA). KFAs are typically completed prior to cutblock development and/or forest road construction. The main goals of a KFA are to determine: a) The extent of the karst area (or unit) and any associated non-karst catchment areas (that might drain onto the karst unit); b) The location and types of any notable karst surface features (which may need to be evaluated individually for their significance); c) The vulnerability of the broader karst landscape (which includes the estimation of subsurface karst development); d) The nature and characteristics of streams on and flowing onto the karst unit; and

The karst solution processes start with rainfall that dis- solves CO 2 from both the air and soil, and forms a weak carbonic acid. This weak acid infiltrates fractures and reacts with the limestone, dis- solving the bedrock. The inset illustrates the three-dimen- sional nature of a karst land- scape and the connectivity between the surface and subsurface environments, with linkages between air, water, rock, soil and biota.

on the surface and underground, is often valued for recreation and tourism. Forestry Activities and Karst Landscapes In BC, forestry is the primary land-use activ- ity where there is a significant need for karst assessment and management—particularly on the BC coast where timber resources occur in areas underlain by well-developed karst lands (e.g., Northern Vancouver Island and Haida Gwaii). In 1997 karst was first recognized by the BC govern-

e) The nature, extent and depth of any caves. Determining the extent of the karst unit requires experience with field mapping, geology and karst geomorphology. The loca- tions of individual karst features can be established using ground searches (incorporating information from aerial imagery and field knowledge of karst processes), and by using handheld GPS devices for positioning. (LiDAR data have also been found to be useful in identifying karst depression features such as sinkholes.) Careful description and evaluation of any karst features encountered is required, as this often provide clues as to the nature and the karst

ment as a functioning landscape system with elements that needed careful protection and management. This led to the development in 2003 of two key documents for the inventory, evaluation and management of karst landscapes: the Karst Inventory Standards and Vulnerability Assessment Procedures for BC (KISVAP) and the Karst Management Handbook for BC (KMH). Both of these documents, though 10 years old, continue to provide essential guidance for forestry activities on karst lands in BC. With the advent of the Forest and Range Practices Act (FRPA) , professional reliance is now used to support implementation of

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