Using GIS to measure changes in the temporal and spatial dynamics of forestland: experiences from north-west Spain M.F. MAREY PÉREZ*, V. RODRÍGUEZ VICENTE and R. CRECENTE MASEDA Department of Agroforestry Engineering, University of Santiago de Compostela, Campus Universitario s/n, 27002 Lugo, Spain *Corresponding author. E-mail:
[email protected]
Summary Forestry variables are usually calculated at a forest management unit scale. However, a region’s forestry sector is affected by various other factors that interact over space and time, many of which are not directly associated to silvicultural activities but nonetheless play an important part in its development from a socio-economic or environmental point of view. To understand a region’s forestry dynamics, and especially to predict its future tendencies, we must include all the necessary variables in a single database, calculated for spatial units that are stable over time and adequate for planning purposes. In our study, we developed a Forest Geographic Information System for Galicia called ‘SIFGa’. We used it to examine 310 variables describing the environment, population tendencies, land tenure and forest management in the Spanish autonomous region of Galicia, at both council and parish levels. Results reveal the connections between our variables, which reflect the changes the regional forestry sector has experienced in the past, and explain its current situation. They also confirm the heterogeneity of forestry in the area and the need to adapt forest-planning strategies to each study unit, as well as to the entire region.
Introduction: setting the stage Galicia, a Spanish autonomous region situated in the north-west of the Iberian Peninsula (Figure 1), covers 3 million ha and has 3 million inhabitants, which correspond to 5.8 per cent of the country’s territory and over 6 per cent of its population (INE, 2002). © Institute of Chartered Foresters, 2006. All rights reserved. For Permissions, please email:
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In this predominantly agricultural region, there are still strong ties between its inhabitants and the land. Its history, especially land use changes during the nineteenth and twentieth centuries, resulted in a rural landscape that contrasts with the rest of the country, based on the central role of the ‘family agro-forestry holding’. In the nineteenth century, large grazing areas began to be Forestry, Vol. 79, No. 4, 2006. doi:10.1093/forestry/cpl027 Advance Access publication date 3 August 2006
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Figure 1. Location of Galicia in Spain (Europe) and its four provinces.
divided up because of population growth and the need to increase farm income. The present-day mosaic of small land holdings, characterized by the fragmentation of individual forest property and insecurity of land tenure of common land, is a result of this process (Marey, 2003). The agro-forestry system changed even more remarkably during the 1950s, for mass rural emigration hindered the development of a competitive agricultural sector – despite the previous agricultural intensification – causing instability at the socio-economic and land use levels (Etxezarreta, 1979). As in other European countries, production stopped on a significant number of farms, thus transforming land management and land patterns themselves: farm-level changes in land use are widely acknowledged as a response to decreasing agricultural economic viability. Today, Galicia is still the Spanish region with the highest percentage of farms, smallholdings and rural population, but a low percentage of the country’s agricultural production. The expansion of forest plantations is another response to shifting economic conditions, and commonly associated with population loss. The lack of farm labour caused much land to become abandoned and progressively occupied by scrubland and native woodland. In order to counteract this tendency, the Spanish government’s forest policy – begun in the late nineteenth century and reaching a peak in the mid-twentieth century – encouraged the increase of forest plantations for
the fibre and chipboard industries. At present, Galicia is one of Europe’s major forest regions: forests occupy over 60 per cent of it, which is 20 per cent above the average forest cover in Spain (MMA, 1998). This is also higher than central European countries like Germany or Austria and Nordic countries such as Norway; in fact, the percentage of forest cover is only surpassed by Finland and Sweden (UNECE/FAO, 2000). Our analysis of Galicia’s agro-forestry data identified a series of key issues for the development of a competitive forest sector on a global scale, presented in Table 1. Galician forest management must now face new challenges in order to evolve from its underproductive, and in some places neglected, state. Recovering confidence in this resource will demand a coherent effort to ‘increase’ and ‘take advantage’ of the sector’s strengths and opportunities, as well as to ‘correct’ and ‘avoid’ its main weaknesses and threats (Table 1). To achieve this, the sector must undergo ‘strategic planning’ from structural, social, economic and political perspectives, so that forestry is seen as a ‘clear socio-economic opportunity’ in the region. Galicia’s complex forest history stems from many variables that are interconnected over space and time; any evaluation of forest sustainability must consider the dynamics of these variables. We need to gather, validate and link information on forestry, as well as other parameters of population dynamics and structure, land use and
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Table 1: SWOT analysis for Galicia’s forest sector (Marey, 2003) Strengths Land suitability for forest use Highly representative forests High standing volume and growing stock Main timber producer for Spain Strong ties between owners and their land Weaknesses Absence of a ‘forestry tradition’ Property fragmentation Low quality of wood products Small size of forest enterprises Lack of economic knowledge
Opportunities Multi-purpose forest management Growing environmental awareness Potential forest incentives Growing demand for high-quality wood products Development of forest owner associations Threats Continuing rural exodus Ageing population Deterioration of the family farm High rural unemployment Weak communication structures
SWOT = Strengths, Weaknesses, Opportunities, Threats.
management. Only if we adopt an integrated approach to the sector, including rural dynamics as well as economic issues, will we be able to recommend forest development strategies to support sustainability in rural areas; this is the concept of ‘Rural Development Forestry’ (Slee and Snowdon, 1999). Our study used a systematic diagnosis to identify and describe homogeneous forest areas in Galicia building on a previous study that related characteristics of homogeneous units to ownership (Marey, 2003). Therefore, the ultimate aim of this grouping will be to develop a suitable framework to design planning strategies for the region, as well as specific political measures for each of the forest areas identified previously.
Methodology The SIFGa framework In designing our research methodology, we needed to determine (1) which variables to study and which sources to use (selection–validation), (2) which system would store the information gathered (storage) and (3) how we would organize and combine stored information (classification–integration) to decide (4) how to analyse it (forest analysis). We used various sources of information on rural property, which were validated and brought together to attain the objectives discussed in Materials and methods. Validation ensures that the model has been developed correctly, by com-
paring its outputs with real system values. We chose variables from studies of the forestry, farming and/or livestock production sectors, as well as others such as demographic and socio-economic variables. Specifically, our sources were the Land Register, Cadastre, National Agricultural Survey and National Forest Survey and Map (Figure 2). The ‘Spanish Cadastre’ is a compulsory public register of land ownership, land values and land use for taxation purposes, while the ‘Spanish Land Register’ is a voluntary legal register of property ownership. We stored our variables using Geographic Information Systems (GISs) in vector format, which are very useful tools for storing, processing and manipulating spatial databases. GIS models have become an increasingly important tool to facilitate ex ante evaluation of forestry policy and management, given that such an assessment requires the prediction of changes in interacting rural characteristics over a medium to long time frame. We built ‘SIFGa’, Galicia’s Forest Geographic Information System, as part of a larger research project on forest property in the region (Marey, 2003). In SIFGa, forest patterns were described by mapping land use, land tenure and management units. We used the lowest scale of administrative units in the region – councils and parishes – as the study units that would best reflect its complex forest use (Figure 3). (The ‘council’ is the basic legal geographic unit set up according to the Autonomic Regulation no. 5/1997 of 22 July 1997 on ‘Local Administration in Galicia’, whereas the ‘parish’ constitutes the traditional area of agro-forestry land holding in Galicia.)
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Figure 2. Framework for the SIFGa design and development.
Figure 3. Council distribution in Galicia and parish distribution in one council (using the Castroverde council as an example).
Finally, validation of variables used in our SIFGa model was a difficult task because it involved many parameters that affect the model’s ability to forecast outcomes of forest management options. We therefore chose statistical analysis as the most effective tool for managing large amounts of data (Figure 2). Data were examined in various stages, using different statistical analyses, followed by ranking and a synthesis of the
main characteristics of forest use, structure and management. Materials and methods Source validation and variable selection We examined the sources illustrated in Figure 2, considering the following points: definition, legal basis, scope, information gathered (graphic and
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alphanumerical), aim and responsibilities, land tenure, revision period, accessibility, reliability and possible application to Galicia as an information source in SIFGa. We concluded that the Cadastre, Third Spanish Forest Map (MMA, 1999), 1972–1999 series of National Forest Survey (MMA, 1998) and 1962–1999 series of National Agricultural Survey (INE, 1999) were the most adequate and reliable sources on land tenure and use for our study. We then selected relevant variables, which given their high number (310), we divided into four groups by study parish and council: 1 ‘Identification variables’. These were essential for the implementation of SIFGa, for they identified administrative study units by means of code and text fields. 2 ‘Environmental variables’. Obtained from 1 : 200 000 maps from the National Geographic Institute and Galicia’s Forest Plan, we included them for their information on the regional landscape’s history and present state (Liu and Andersson, 2004). We divided them into ‘physiographical’ and ‘climate’ variables. 3 ‘Socio-economic variables’. We used these because of their role as drivers of land use change (Mansfield, 1961; Rosenberg, 1976; Stoate et al., 2001) and divided them into two types: ‘Demographic’. Produced by the National Statistics Institute, this alphanumeric database allowed us to study past population changes and predict future ones by study parish and/or council. ‘Agricultural structure’. By studying how the structure of rural property (i.e. the number, size and dispersion of units that compose a farm holding) has evolved, we gained an insight into the evolution of land use on those properties. Our main source of information was the National Agricultural Survey, an alphanumeric database with the individual farm holding as the analysis unit. In the present study, these data were structured by mean, minimum and maximum values at the Galician council level. 4
‘Forest property and management’. Here we used the Cadastre and data from Galicia’s Environmental Council (part of regional
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government) as sources of information on land tenure. Within this group, we classified variables into four types: ‘Forest use’. We used the Third Spanish Forest Map at scale 1 : 200 000 to describe forest composition and cover at council scale, developing an alphanumeric and graphic database with the tessera as the analysis unit (i.e. the number, size and dispersion of tesseras that compose a specific land use). Moreover, these data were structured by mean, minimum and maximum values at Galician council level. ‘Forest industry’. During recent years, the main wood consumers in Galicia have changed from family-owned sawmills to large pulp mills and fibre/chipboard industries. During the same period, native forests have been replaced with plantations of fast-growing forest species (such as Pinus pinaster Ait., Pinus radiata (D.) Don. and Eucalyptus globulus Labill.) to supply these industries with raw material. Given the relation between forest industry and forests, studying these companies is useful in developing strategies to support forest harvesting and rational transformation of wood products. ‘Forest subsidies’. Within the European Union’s Common Agricultural Policy for the last decades, one of the subsidies with highest forestry impact was the one that supported afforestation of arable land (Regulation 2080/92), and thus modified land use (Geist and Lambim, 2002; Croissant, 2004). ‘Forest fires’. As one of the main threats to forests in Mediterranean countries, its analysis identified fire-prone areas as part of the regional fire-fighting strategy. These last three types of variables – forest industry, forest subsidies and forest fires – were obtained from alphanumeric public surveys and implemented in the GIS model by parish and/or council, in the same way as the agriculture structure and forest uses variables. Variable storage: a GIS model The SIFGa was constructed using the ArcView™ and ARC-INFO™ modelling software for data processing in order to store, update, process and manipulate spatial features with a temporal component. We used a digitized map (scale of
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1 : 5000) from Galicia’s Land Planning Council as the cartographic basis which allowed us to display visually the forest units of study, i.e. the Galician municipalities and parishes. The spatial features from the previous surveys were digitized over digital maps and the alphanumeric data were stored on text files. All the selected variables were converted to a vector format map layer with the alphanumeric information linked to these two analysis units. We chose to join the fields in a single database and a single map, which we found to be more adequate than the GIS with superimposed ‘layers’ for the various queries. Variable classification and integration: a spatial perspective Because we wanted to analyse variables from different sources, we had to homogenize and optimize them before integrating them in the GIS. To begin with, the variables were assigned to each spatial study unit: the 315 councils and 3793 parishes in Galicia. The extensive range of variables compiled in the survey illustrated the considerable heterogeneity of Galicia’s agro-forestry system, reinforcing the need to group the variables in order to interpret and validate the results. We then extracted and grouped those most closely correlated with Galicia’s forest system and with the most significant factors of each common factor analysis. Cluster analysis was used to differentiate four variables particularly representative of the differences in forest use, structure and management as provided by the full set of original variables. These variables, which facilitated the interpretation and validation of the statistical results, were forest area in communal ownership (percentage of communal tenure), forest area (percentage of forest cover), forested forest area (percentage of forested forest cover) and forest area in public management (percentage of State-managed forest), variables which are described below. We also included ‘non-forested forest area’ (percentage of non-forested forest cover) because of the importance of small areas of sparse woodland, which is not included in the ‘forested’ category, in supporting the traditional agrarian system in Galicia. In order to answer our main research question and considering that these five variables present
any number of responses from a set of pre-defined items, we re-defined and coded them in five new categorical variables that summarize our data survey and satisfy the assumptions of statistical analysis. For this step, and because we did not have reference studies, we applied simple statistical criteria using the programmes SAS-SPSS™ and STAT-GRAPHICS™ (Marey, 2003). Firstly, we produced descriptive statistics and frequency histograms for the grouped variables and, subsequently, we selected statistics of location and dispersion, i.e. the mean χ– and standard deviation σ, respectively (Cao, 2002). Then, we considered this location measurement ( χ– ) as the centre of these grouped variables and calculated the class intervals from the dispersion statistics (σ). These categorical variables are described as follows: 1 Percentage of communal tenure. This variable represents a communal form of land tenure typical of Galicia and unique in Europe, named ‘Montes Veciñais en Man Común’. In this forestland property, land is owned by a neighbours’ assembly, where each neighbour represents a rural family or house. This variable – communal tenure as a percentage of council forest area – reveals the relative proportions of individual and communal tenure in each council. Table 2 shows that 25 per cent of the councils have no communal woodland at all, and in only 38 councils is more than twothirds of the forestland owned collectively. The predominance of individual tenure is typical of European countries. 2 Percentage of forest cover. This variable – percentage of council area occupied by forest – illustrates the importance of forest as a land use. On average, forest occupies 64.8 per cent of the land area of Galician councils. As seen in Table 3, forest is the dominant land use in almost all councils; in over 60 per cent of them, forest covers more than 60 per cent of their area, and only 13 councils have less than 30 per cent forest cover. 3 Percentage of forested forest cover. This variable consists of the council’s forested area as a percentage of council forest area. The difference between forest and forested area is very important and due to our use of FAO’s (2004) definition of ‘forested area’, which is land with more than 10 per cent tree crown cover
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Table 2: Communal woodland as a percentage of total forest area in Galician councils Class
Communal tenure (%)
Number of councils
Total councils (%)
0 1 2 3 4 Total
67.81 –
81 57 55 83 38 314
25.8 18.1 17.5 26.4 12.1 100.0
Table 3: Forest as a percentage of total council area in Galicia Class
Forest cover (%)
Number of councils
Total councils (%)
1 2 3 Total
£34.40 34.41–64.80 >64.80 –
13 135 166 314
4.1 43.0 52.9 100.0
(or equivalent stocking level) and over 0.5 ha. This includes areas normally forming part of the forest area that are temporarily unstocked but expected to revert to forest and scrubland that is likely to develop into forest. In Spain, ‘forest areas’ often include a very significant amount of scrubland, native woodland and uncultivated land in general. In our study, the average forested area per council exceeded 70 per cent of forest area, indicating the productive function of the region’s forests. As presented in Table 4, in almost all councils (almost 95 per cent), the forested area comprises more than 40 per cent of forest area and, in more than half of them, forested areas exceed 78 per cent of total forest area. 4 Percentage of non-forested forest cover. This variable complements the previous one; it is defined as non-forested area as a percentage of council forest area. The average is 22 per cent, but although in over 180 councils non-forested areas are relatively few, in 5 per cent of them, most of forest area is actually scrubland. 5 Percentage of State-managed forest. This variable applies to parishes; in our study, we only looked at those in the Lugo province. It evaluates the importance of private vs state forest
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Table 4: Forested areas as a percentage of the total forest area in Galician councils Class
Forested areas (%)
Number of councils
Total councils (%)
1 2 3 Total
£41.60 41.61–78.10 >78.11 –
16 116 182 314
5.1 36.9 57.9 100.0
management (the latter mainly undertaken via ‘consortiums’ and ‘agreements’ with private communal owners), and is defined as State- managed forests as a percentage of parish forest area. Table 5 illustrates how twothirds of Lugo parishes have only one type of forest management – private. In the other extreme, in 26 parishes, the state manages most of the forest area. The average percentage of the forest area under state management per parish is 28 per cent. To assess the influence of the variables described above on forest use, we carried out a series of statistical analysis, with the aim of examining the following. At council scale, for all of Galicia: The relation between agricultural use and land tenure, as expressed by the variable percentage of communal tenure. Variations in population dynamics and forest use according to land tenure, described by the variables percentage of communal tenure, per centage of forest cover, percentage of forested forest cover and percentage of non-forested forest cover. At parish scale, only for the province of Lugo: The link between land use and type of forest management, given by the variable percentage of State-managed forest. The connections between demographic tendencies and type of forest management, using the variable percentage of State-managed forest. Finally, as regards statistical analysis, we estimated the predictive behaviour of each categorical variable by the correlation between predicted and observed values in continuous dependent
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Table 5: State managed forests as a percentage of parish forest area in the Lugo province Class
State managed forests %
Number of parishes
Total parishes %
0 1 2 3 4 5 Total
74.62 –
863 55 180 117 30 26 1271
67.9 4.3 14.2 9.2 2.3 2.0 100.0
variables of the corresponding SIFGa model. Linear correlation among explanatory variables was examined with Spearman’s coefficient ‘Rho’ (Spearman, 1904) at 0.01 level of significance.
Results and discussion
Figure 4. Box diagram of the relation between the variables percentage of agricultural use and percentage of communal tenure (Rho = −0.352). Open symbol denotes cases with values between 1.5 and 3 times the box length from its upper edge (named outliers). The length of the box is the interquartile amplitude.
Forest patterns at council level Agricultural use and land tenure Arable or livestock farming, combined with forest harvesting, has been the main means of subsistence for Galician rural communities, in a multi-purpose management system that is considered sustainable in many rural regions (Long and Nair, 1999; Sibbald et al., 2001). The loss of this farming system in Galicia, as in most of Europe, is linked to rural population migration (Bičík et al., 2001; Terluin, 2003). It is also partially due to changes that occurred in the farming system itself, as farmers were forced to choose between intensifying production and disappearing from the market place. In this study, the percentage of council land dedicated to agricultural use varied between 6 and 71 per cent (χ– = 31.6 per cent, σ = 13.7 per cent). Figure 4 illustrates the significant negative correlation (Spearman’s coefficient of rank correlation = 1 per cent) between communal woodland and agricultural use, although we cannot establish a direct connection between agricultural area and land tenure. In response to the demands of a market economy, landowners attempted to modernize their
holdings by intensifying production (López, 2000; Vence, 2000). In contrast, landowners in councils with large areas of communal woodland did not have enough land to ensure their farm’s viability (Marey, 2003). Non-forested area per total council area varies between 0 and 66 per cent (χ– = 15.2 per cent, σ = 14.6 per cent). Councils where communal tenure is predominant have significantly more scrubland than those where forest property is essentially private (Figure 5). This reveals the absence of active silvicultural management in communal woodlands; in fact, it is largely attributable to the land having been abandoned that it is forested at all. Individual landowners are the ones who invest in forested areas, as other authors have noted (Hyttinen, 2001; Lillandt, 2001). We can thus distinguish two types of councils: on one hand, those where communal tenure is under 40 per cent and non-forested areas ~10 per cent, and on the other, those where communal tenure is over 40 per cent and non-forested areas reach 20 per cent. Woodland owned by individuals in Galicia is composed of smaller and more dispersed plots
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Figure 5. Box diagram of the relation between the variables percentage of non-forested area and percentage of communal tenure (Rho = −0.367). Asterik denotes cases with values more than three times the box length from its upper edge. Open symbol denotes cases with values between 1.5 and 3 times the box length from its upper edge (named outliers). The length of the box is the interquartile amplitude.
than communal woodlands, small private plots that are common in other regions too (Bockstael, 1996; Turner et al., 1996; Butler et al., 2004). However, for the last 30 years, rural depopulation has led to sharp decreases in investment in common land, because of its negative impact on the continuity of communal land management. Rural exodus is still in progress, and so the traditional agricultural use of common land will continue to give way to scrubland. The percentage of council forestland that is forested varies between 21 and 100 per cent, and again we found a negative correlation between this variable and percentage of communal tenure, whereby an increase in common land is associated to a lower proportion of forested forest cover (Rho = −0.343). As we have noted before, Galicia’s productive forest area has increased significantly in the last decades; we wanted to know what type of tenure productive forest was associated with. We used the variable percentage of council land occupied
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by fast-growing forest species (i.e. P. pinaster Ait., P. radiata (D.) Don., E. globulus Labill. and Populus sp.), and compared it with percentage of communal tenure. Fast-growing forest species occupied between 0 and 76 per cent of council area (χ– = 35 per cent). In fact, both variables are negatively correlated (Rho = −0.156), so that, in those councils with less common land, fastgrowing forest species occupy more area. For individual landowners in Galicia, short-term forest production appears to be an important source of family income (Chas et al., 2002; Marey, 2003), as has been reported in other worldwide studies (Dennis, 1989; Hyberg and Holthausen, 1989; Kuuluvainen and Salo, 1991; Kuuluvainen et al., 1996; Veli-Pekka and Kanto, 2000). Some authors, though, have argued that individual forestry is of little or no economic importance to landowners (Price, 1997; Lonnstedt and Svensson, 2000a, b; Rapey et al., 2001). Population dynamics and forest use according to land tenure During the twentieth century, rural depopulation in Galicia eventually led to an agricultural crisis (Precedo and Vilariño, 1994; López, 2000). It also affected property fragmentation and brought about a situation in which many landowners live far from their land and thus abandon management, as in other regions (Koch and Skovsgaard, 1999; Wickham et al., 2000; Schraml and Härdter, 2002). In addition, the few emigrants who return to their rural origins are usually retired and unwilling to adopt the new management approaches needed to make a profit from their land (MacDonald et al., 2000; Marey, 2003). Considering the national statistics on population, between 1960 and 2001, population density in Galicia dropped by an average of 19.01 inhabitants km−2. Nevertheless, this population decrease has a different intensity considering the degree of forest cover of council. The variables percentage of difference in population density between 1960 and 2001 and percentage of forest cover are negatively correlated (Rho = −0.487), which reveals the influence of population dynamics on current forest cover in Galicia. In councils with less forestland – i.e. where forest occupies less than a third of the council area – population density rose. On the other hand, the councils where forest covers
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over 60 per cent of council area are those where population density has decreased most during the last 40 years. Nevertheless, the trend with population dynamics alters when it is related with the forested forest cover; we found that those councils when more than 78 per cent of forest area is forested experienced a slight population decrease during 1960–2001 (6.4 per cent), while councils with the lowest proportion of forested forest area suffered population losses over 40 per cent (Figure 6). Authors such as Ortoloff (1999), Farrel et al. (2000) or Erickson et al. (2002) have pointed that forest distribution and composition are direct consequences of human intervention, which replaced native woodlands by plantations of fastgrowing species. As MacDonald et al. (2000) have found for many European rural areas, the cessation of traditional activities, combined with demographic and economic recession, alters the balance achieved by traditional farming systems and increases forestland.
As would be expected given the results obtained for forested forest cover, the relation between changes in population density variation and nonforested forest cover indicates how large areas of non-forested forestland are tied to greater population loss (Rho = −0.478), as well as to lower proportions of council area occupied by forestland. Population loss is clearly associated with lack of investment in arable lands, which subsequently turn into scrubland (MacDonald et al., 2000; Butler et al., 2004). Only in councils where population density has been stable for the last years can we find large areas of productive forests – a result of owners living near their land and managing it, independently of its use. Our results support the correlation between forest use, demography and agricultural use. Councils with higher forest cover are less densely populated; here crop and/or livestock production has been abandoned and is being replaced by scrubland, i.e. non-forested forestland. In Galicia, forestland is therefore a ‘social phenomenon’, for human pressure is the key factor affecting land use changes. We also found interesting connections between forest composition on the one hand and tenure and owner profile on the other. Forested areas are chiefly located in councils that have suffered less from population loss and where communal tenure is less frequent. This means that individual owners are the most interested in obtaining income by planting fast-growing forest species. Forest patterns at parish level
Figure 6. Box diagram of the relation between the variables variation of population density and percentage of forested forest cover (Rho = 0.435). Asterik denotes cases with values more than three times the box length from its upper edge. Open symbol denotes cases with values between 1.5 and 3 times the box length from its upper edge (named outliers). The length of the box is the interquartile amplitude.
The Government Forest Administration has managed large forest areas in Galicia since the late nineteenth century, but from 1941 onwards, state intervention in the forest sector was greatly increased by the ‘State Forest Law’ which marked the beginning of large-scale forest planting by the Spanish State. It recommended afforestation of all Spanish areas with forestry potentiality, independently of ownership type, by the owner him/ herself or by the State via consortiums and agreements with the private owner. Given that Galician publicly owned land was scarce, afforestation could only be achieved through partnerships and agreements with individual owners or the entities representing communal lands via financial support programmes.
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Presently, it is applied through the provision of technical advice and forestry extension services and/or state participation in forest management, tools which are better known in European countries that have a longer forestry tradition (Boon and Meilby, 2000; Jensen, 2000; Crabtree et al., 2001; Workman et al., 2003; Tabbush, 2004). In our study, we focused on the impact that financial support programmes (plantation, silviculture and fire-fighting subventions) managed by Galicia’s Forest Administration had on rural systems in the Lugo province’s 1270 parishes. Land use and type of forest management We first attempted to explore the relation between land use and forest management by studying the variables percentage of agricultural use and percentage of State-managed forest. On average, agricultural land occupies over 40 per cent of total parish area in Lugo, but there are two distinct groups of parishes in this province (Figure 7). The first group includes parishes where agricultural land occupies more than the province average and where responsibility for forest management is almost entirely private (class 0 of the
Figure 7. Box diagram of the relation between the variables percentage of agricultural use and percentage of State-managed forest (Rho = 0.110). Open symbol denotes cases with values between 1.5 and 3 times the box length from its upper edge (named outliers). The length of the box is the interquartile amplitude.
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variable percentage of State-managed forest) or exclusively borne by the state (class 5 of the same variable). In class 0 parishes, the privatization of common land that occurred from the late nineteenth century to the mid-twentieth century converted large areas of woodland into pasture, to provide short-term family income for each of the former neighbours of the neighbours’ assembly. In contrast, in class 5 parishes, the government afforestation programme selected flat areas with no scrubland for planting/seeding – that is, traditional grazing areas. Therefore, by force of this expansion of public forest plantations, the remaining less productive communal areas were progressively occupied by new grazing areas with more intensive agrarian production. Considering this land use change on communal lands of parishes in classes 0 and 5, these lands were gradually fragmented to meet the agrarian requirements of rural population, reducing the woodlands to the bare minimum. The second group consists of parishes where agricultural land occupies less than the province average (~ 30 per cent), and private and state management coexist in varying proportions (classes 1, 2, 3 and 4). In this case, the lower percentage of farmland is associated with government afforestation efforts, which caused many active farm holdings to cease production. The more proactive owners chose to forest their land, while those who emigrated simply abandoned it to scrubland, as explained earlier. We also studied the government’s role as a provider of information and training services to private owners (Andersen et al., 2002; O’Brien, 2003). Thus, we examined the current state of forest areas in Lugo parishes according to the existing State forest management. As shown in Figure 8, the relation between percentage of nonforested area per parish forest area and proportion of State-managed forests also points towards two distinctive groups of parishes. The first group contains parishes with the least area under state management (class 0 of the variable percentage of State-managed forest) and those where almost all forests are state managed (class 5); in both cases, scrubland occupies less than 10 per cent of the parish forest area. The second group includes parishes in classes 1, 2, 3 and 4, where forest management type is mixed to varying extents. In this case, the average percentage of scrubland is 14–20 per cent. This result
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that fast-growing species generally occupy higher proportions of land in parishes with more forest area under state management. More than 67 per cent of forestland of Lugo parishes is privately managed; only in 2 per cent of them is it entirely state managed. These parishes, where forest management is neither exclusively private nor the state’s, have not only the highest concentration of fast-growing forest plantations but also the highest forest cover in general. Again, we note how rural exodus and low farm revenue clearly influence forest cover. However, we would also like to stress the individual landowner’s financial interest in fast-growing forest plantations as a means of obtaining income from their former arable lands, as well as the state’s interest in revitalizing rural areas suffering from population loss and land neglection. Figure 8. Box diagram of the relation between the variables percentage of non-forested (parish) forest cover and percentage of State-managed forest (Rho = −0.121). Open symbol denotes cases with values between 1.5 and 3 times the box length from its upper edge (named outliers). The length of the box is the interquartile amplitude.
completes the previous section on the agrarian use on communal lands; mixed forest management in these parishes created potential conflicts between State foresters and the local population, as a consequence of the alteration of the traditional modus vivendi and radical changes in rural landscapes. These social conflicts may be the cause of the lack of interest of the rural population in woodlands, leading eventually to outright opposition to public forest management expressed by means of arson and agrarian occupations (Villares, 1982; Rico, 1995). The Government Forest Administration should supply information and training for landowners by providing an example in the forests it manages. Today, it manages almost half of Galicia’s communal woodlands, i.e. ~15 per cent of the region’s forest area. We investigated the success of the example provided by the state by searching for a possible correlation between the variables percentage of parish land occupied by fast-growing forest species and percentage of State-managed forest. As we expected, we found a positive correlation between both variables (Rho = 0.107), so
Demography and type of forest management Currently, the average population per parish in Lugo is 55.5 per cent of what it was in 1960, with considerable variation among parishes (0–806.1 per cent), as revealed by the high standard deviation (σ = 32.6 per cent). However, our comparison of population tendencies with forest management type revealed no correlation between the degree of state intervention and demography (Rho = 0.050), contrary to what authors such as Balboa (1990) have found.
Conclusions Recent national and regional surveys show an increase in the forest and productive forest cover in Galicia autonomous region, where the distribution of forests results from major changes in land use over the last century. Nevertheless, a more detailed analysis of its forestry expansion at local scales, that is, council or parish levels, shows differences in the forestry variables, as a result of different change processes. This temporal evolution – not only at the parish level but also at the municipality level – has been clearly influenced by the land tenure regime and, as expected, by the land management carried out. Thus, forest ownership characterized by either solely private or solely public management showed a higher incidence of more productive forest types than the mixed management.
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In addition, the demographic aspects linked to these territorial units have contributed, directly or indirectly, to these forestry changes. So, densely populated areas have increased their forestland towards woodlands for timber production, although the environmental component of sustainable forest management requires a special weight given the strong urban and population pressure. On the other hand, the area of productive forestry did not increase in highly depopulated areas (unlike other forestry regions) because the economic incentives were insufficient to promote a future owner’s interest. Our results demonstrate the importance of considering how different rural variables interact and vary over time and space, in order to obtain detailed and consistent information on specific areas, and to develop planning and management policies at different scales in Galicia. We found two administrative units to be the most appropriate planning unit at all decision-making levels, the municipality and the parish. Therefore, the development of tools to support forestry decision making in Galicia – ‘strategic’, ‘tactical’ and ‘operational’ – requires solid sources of agroforestry information, which should be defined consistently for all councils, and especially for all parishes of this autonomous region. On this premise, we developed the SIFGa model, a GIS tool to forest decision making. We thus recommend the rural parish as the basis for the future development of District Forest Plans and Territorial Plans (strategic planning) as well as for implementing and evaluating rural or forest policy (tactical planning), for example. Government intervention is crucial, and should combine instruments such as state participation in forest management, landowner training programmes and land consolidation. To this end, existing government measures must be adapted to Galicia’s current agro-forestry situation, revitalizing a historically agricultural region and, in particular, stimulating the potential of its forest sector. References Andersen, F., Konijnendijk, C.C. and Randrup, T.B. 2002 Higher education on urban forestry in Europe: an overview. Forestry 75, 501–511. Balboa, J. 1990 O monte en Galicia. Ed. Xerais, Vigo, 359 pp.
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Received 29 June 2006
