The National Forest Inventory (IFN) is a project of the Ministry for Ecological Transition and the Demographic Challenge that provides homogeneous information at a national level on Spanish forests and their evolution, both from a forestry and forest biodiversity perspective. This project is structured over time with a ten-year periodicity (art. 28 of the Forestry Law), and after 60 years of validity, it is finishing its fourth cycle (IFN4), which began in 2008. The permanent nature of the field plots implemented since IFN2 allows for a continuous source of information when analyzing the behavior of forests over time. The minimum unit of the IFN is the plot, which details the existence of the different main parameters such as volume with and without bark, basal area, number of major and minor trees, annual increase in volume with bark, tree biomass and fixed carbon, among others, in addition to indicators such as the number of tree and shrub species present in the plot, the average height of Assman or the mean quadratic diameter. Other data are also shown such as the 3 main species of the plot, their state of mass and occupation or the municipal term where the location of the plot is included.
Spain