Presentation of landscape-fuzzy approach of forest capability evaluation (LFAFCE) for degraded sites

Evaluation of forest sites capability (EFSC) is important for the restoration of degraded areas. The current costly EFSC approaches developed based on forest stand structure criteria is too costly for less developed countries (LDC) and not suitable for severely degraded lands. This paper describes an inexpensive Landscape-fuzzy approach for forest capability evaluation (LFAFCE) that can be used to restore degraded forest areas especially in LDC. Five physical criteria of slope, hillshade, altitude, precipitation, and geo formation were evaluated in the Zagros region of western Iran using the fuzzy membership functions, prioritized by analytic network process (ANP), and combined with GIS-based weighted linear combination. We then performed multi-criteria evaluation integrated by GIS. Given the positive correlation between the independent variable of EFSC and the dependent variable of the dominant tree height, the model results were validated based on the linear regression of the relationship between the two variables. The results of the validation showed that the linear regression model with appropriate coefficient of determination was significant. The results of EFSC by LFAFCE showed that most of the forest area was allocated to two classes: well (75%) and moderate (21.8%). In total, only 3.2% of the area belonged to the marginal (0.4%), high (0.1%), and unsuitable regions (2.7%) classes. Our results demonstrate that LFAFCE is valid for low-cost evaluation of degraded area in Zagros and for other similar areas, if calibrated, where normal forest mass parameters are not available.