# Forest Dynamic in the Italian Apennines
## 3 Results  
On the basis of the LULC maps obtained for the years 1954 and 2016 (see Appendix A, Figure A1), the variation for each of the twenty LULC classes identified was calculated and is summarized in Table A1 (see Appendix A) and shown in Figure 5.  
In the study area covering 82.83 km\({}^{2}\) above 1300 m asl, the reduction of the Xerophilic mesophilic grassland is considerable (18%), although it remains the most widespread LULC, covering about 30% of the whole area. A relevant increase in the class \"Compact deciduous forests with fine texture\", that has almost tripled its surface, is observed, and  
Figure 6: Dynamic of Renaturalization in the period 1954–2016. Figure 7: Clearings dynamics in the period 1954–2016. in 2016 they represented 24% of the study area. Additionally, high is the variation of the class \"Structured deciduous forests\" which increases from 2% up to 11% of the total area. A reduction of \"open deciduous forest\" can be observed, which now, overall, has reached 11%, being equal to 22% of the study area in 1954. The marginal agricultural fields cultivated with cereals or mountain legumes, which represented 2.6% of the surface in 1954, have completely disappeared. The transition matrix among the 20 classes (see Appendix A, Table A2) provides the direction of transformation which occurred and highlights the intense and relevant process of the increase of the crown cover density. In order to highlight the main trends of transformations, a transition matrix analyzing the six macroclasses has been produced (Table 4). The transition matrix of macroclasses highlights a relevant increase of Forests (Net change of 5.22 km\({}^{2}\)) mainly to the detriment of Grassland and to a lesser extent of Shrubs; also, the class Shrubs shows a net change of 1.08 km\({}^{2}\), mainly deriving from a loss of Grassland. A transition from Shrubs to Forest can be observed too, while the class Arable land is almost totally turned into Grassland. Considering the Swap values, Grassland are the most dynamic class with the highest surface subject to changes both in terms of acquisition (essentially from Arable land) and in terms of substitution towards Shrubs and Forests. Moreover, the class Shrub is strongly dynamic, showing a transition to Forests and a contemporary noticeable acquisition from Grassland. Considering Lp, Gp and Cp, the class Shrubs show the most relevant dynamic and show the greatest attitude to change and, specifically, to increase its surface, being Gp > 1. The rate of transitions, calculated simply as the ratio of the net change to the time interval, points out a relevant annual average change for the classes Forests, Shrubs and Grassland. The classes \"Structured deciduous forests\" and \"Compact deciduous forests with fine texture\" show, respectively, an increase of the mean annual area of 12 and 19 ha y\({}^{-1}\), that is lower than the values described in other studies carried on in the Apennines [11] (Table A1). Analyzing the dynamics of forests' structures, an evident trend to the closure of forests is highlighted by an increase of compact structures and a decrease of open and sparse formations. These results clearly show the reduction of the anthropic pressure, the transition from Grassland and herbaceous formations towards Forest systems and the triggering of an ecological succession. In order to describe the dynamics of renaturalization, the difference between the NI scores of 1954 and the NI scores of 2016 on the basis of the detailed LULC maps with 20 classes has been calculated as a raster map (Evolution of naturalness map, Figure A2). The map represents, for each pixel, the extent of the process in terms of the number of jumps in the hierarchical scale of naturalness. For example, a pixel with a value of 6 must be interpreted as a transformation of the historical land use that has 6 steps forward in the 17-step staircase (e.g., a meadow that becomes very sparse wood). In the map, negative values indicate a renaturalization process while positive ones denote the opposite process.