Classification and mapping forest sites using geographic information system (GIS): a case study in Artvin Province

Area of Science:

• Forestry
• Ecology
• Soil Science

Background:

• Traditional forest management often relies on indirect methods for site productivity assessment, primarily focusing on timber production.
• Implementing ecosystem-based multipurpose forest management necessitates a direct approach to determining forest site productivity.

Purpose of the Study:

• To distinguish and map forest sites using both direct and indirect methods in the Genya Mountain region.
• To compare the outcomes of direct forest site classification with indirect site index estimations.

Main Methods:

• Conducted field studies across 112 sample plots, collecting soil samples and timber inventory data.
• Employed the Soil Moisture Regime (SMR) method, utilizing water holding capacity and physiographic factors (landform, aspect, slope) for direct forest site classification.
• Generated anamorphic site index (SI) equations using a guiding curve for indirect classification.

Main Results:

• Five distinct forest site classes were determined using the direct method: dry, moderate fresh, fresh, humid, and hygric.
• Three site index classes (good, medium, low) were established via the indirect method, showing significant area discrepancies compared to direct method classifications.
• GIS was used to create comparative forest site maps for both methodologies.

Conclusions:

• Direct forest site assessment, particularly using the SMR method, is essential for accurate mapping and management, especially in areas with water deficiency.
• The direct method is recommended for determining forest sites in open and degraded areas.
• Significant differences in area estimations highlight the importance of choosing the appropriate method for forest management objectives.