**3. Results**

The investigation of the changes in the land cover of the Gorganroud watershed showed that during the study period (1984–2012), the largest amount of changes occurred in the field of forest cover destruction (77,214 hectares), and the largest amount of increase is related to agricultural use (28,866 hectares) (**Table 1**).

*A Study of the Comparison between Artificial Neural Networks, Logistic Regression and Similarity… DOI: http://dx.doi.org/10.5772/intechopen.111615*


#### **Table 1.**

*Changes in all classes of land cover in 1984 and 2012 in terms of hectares.*

**Figure 4** shows the increase and decrease for each user class during the period of 1984 to 2012 based on the percentage of the study area. The largest increase observed during this period is related to agricultural use (with an increase of 1.2%), and the largest decrease occurred in dense forest use (with an increase of 1.54%).

As **Figure 5** presents, forest destruction during the years 1984 to 2012 mostly occurred in the northeastern part of the area. Severe erosion in the loess soils and destructive floods in this region are among the most important reasons for forest degradation in the northeastern part of this area [42].

#### **Figure 4.**

*Gains, losses, and net change for each land cover category between 1987 and 2012 in percentage of the study area.*

**Figure 5.**

*Spatial distribution of deforestation. A: Transition of forest cover between 1984 and 2012; B: Spatial trend of changes (deforestation) between 1984 and 2012.*
