It is important today to take account of the opinions of both experts and stakeholders in the sustainable management of forests. SILVANET (Universidad Politécnica de Madrid, Madrid, Spain) is a software package that offers a useful methodology for assessing the preferences of individuals or groups, and applying them to the design of a sustainable forest management plan. The program starts by identifying the personal preferences of the evaluators based on information provided individually when comparing and selecting sustainability options from a series of site pairs. The evaluator is given information on certain sustainability indicators obtained in the area to be assessed. The scope of the evaluator’s knowledge of sustainable forest management and the consistency of his/her decisions is assessed, and he/she is then included in a group of people with similar systems of preferences to encourage interaction between evaluators in the same group. The preferences are characterized by matrices that encode individual assessments, the maximization of their utility and the analysis of past decisions. Finally, by identifying preferences, we are able to design the forest management system that maximizes the concept of sustainability for each individual or group of individuals. In this paper, we present the results of its application to mono-specific conifer forest stands, although it can be adapted to other forest types. The forestry management experts classify its usability as good, although non-expert users give it a lower rating.

The determination of an asset’s economic value has always been an important step in improving its management. The Madrid Region legislated the application of the first version of the Norma Granada as a method of appraising ornamental trees. However, the trees in the city of Madrid are only assessed in terms of ecosystem services (i-Tree Eco). A photograph of the asset to be appraised is often used in studies on the valuation of publicly-owned socio-environmental assets such as trees or landscapes. As a tree’s value is very closely linked to its size and to a number of features that can be seen through direct observation of the specimen, it is important to verify the validity of photographs as a method for obtaining the public’s opinion. This work presents a comparison between the valuations chosen by members of the public when observing the tree in situ and in a photograph. The aim is to verify the validity of photographs for their application to a larger sample and to understand qualitatively how citizens assess the trees in a city. The following appraisal methods were used: the American method, Council of Tree Landscape Appraisers (CTLA), Norma Granada and the Burnley method. The survey consisted of ten specimens from ten different species, and ten surveys were taken for each stem, making a total of 100 for each tree species and 1000 surveys in all. The surveys were done randomly and individually. Each interviewed chose one of the three values they were shown when observing the specimen in the photograph and in situ; 84% of the 1000 surveys gave as a result the same value choice when looking at the specimen on site and seeing it in a photograph.

Urban trees are generally considered to be a public asset and are an important part of a city’s heritage. The aim of this work is to analyse the influence of season on the economic appraisal of various trees in Madrid. Photographs were taken of 43 individual tree specimens in summer and winter. The survey was designed to compare differences of opinion in the economic assessment of trees. The trees were assessed by eight valuation methods used worldwide. A total of 78 agroforestry engineering students answered a written survey, and the variables considered were: percentage of students who always evaluated the tree equally (%0), percentage of students who assigned more value to the summer photograph (%S), and percentage of students who assigned more value to the winter photograph (%W). The results were analysed by the statistical test of equal proportions and ANOVA to detect differences according to tree type (evergreen or deciduous), species, and other groupings made by the authors in previous works. W and S percentages are similar. The ANOVA analysis rejects the equality of percentages of S and W between groups. The Welch test rejects the equality of the percentage of S, W, and O between species.

We present a new method for the classification of beech (Fagus sylvatica L.) forest plots based on discriminant and frequency analysis. This method can be used as a tool to allow experts to stratify beech forests in a simple and precise way. The method is based on discriminant analysis with cross-validation of 13 variables measured in 142 plots from the 2005 Second National Forest Inventory and 63 plots from an inventory installed in specific locations together with a frequency analysis of the qualifying variables. In the first stage, the method uses the results of a frequency analysis fitted with an iterative discriminant analysis that allows improving the subsequent classifications taking into account the results of the analysis and the correctly- and wrong-classified plots. This method is applied to beech forest in Burgos (Spain) where six structural groups were described. The discriminant functions show that forest structure depends basically on diameter distribution and almost 94% of the plots are correctly classified using this methodology. The high level of correctly assigned plots indicates an accurate classification of structure that can be used to stratify beech forests with only the diameter at breast height measurement.

Rural depopulation is related to several socio-economic variables, including services, transport, communication and employment, among others. This paper assesses the influence of irrigation systems as population fixers in rural municipalities. For this purpose, a national survey was carried out in which the inhabitants of rural municipalities were asked about relevant aspects of depopulation in relation to the presence of irrigation systems in the area. A questionnaire was drawn up, based on expert judgement, containing 45 questions with dichotomous and Likert type answers. The answers were analysed by studying the dependence of the answers on the presence of irrigation systems in the areas surveyed. The results show that rural dwellers are satisfied with life in rural areas, giving greater importance to health and education services, access to the Internet, job opportunities and transport. It is observed that irrigation is perceived as a positive element in both irrigated and non-irrigated municipalities.