The contribution of chestnut orchard recovery projects for effective area-based conservation: Two cases in Asturias (North-West Spain)
ECOAGRASOC. Higher Polytechnic School. University of Santiago de Compostela; GIS-Forest Research Group, Universidad de Oviedo; Department of Geography, Swansea University
DATE OF SUBMISSION
Socio-Ecological Production Landscapes and Seascapes (SEPLS) frequently illustrate potential synergies between socio-economic development, multifunctional use of land, preservation of traditional knowledge, enhancement of ecosystem services and the conservation of biodiversity. As such, efforts for the conservation and enhancement of SEPLS can be considered aligned with “Other Effective Area-Based Conservation Measures” (OECM), as defined by Aichi Biodiversity Target 11, established by the Convention on Biological Diversity (CBD) to be attained by 2020. The utility of such areas and practices underlines the importance of acknowledging diversity in approaches to conservation and sustainable use of biodiversity, as well as the integration of communities through local initiatives. Despite this fact, many SEPLS lack specific protection frameworks or measures, as they are sometimes difficult to define clearly as nature conservation entities. However, other measures related to the enhancement of socio-ecological systems themselves can be useful for the maintenance of their nature conservation capacity. In this study we present a project for the recovery of sweet chestnut (Castanea sativa Mill.) orchards in two public forests, Caranga Baxu and Villamorei, in the region of Asturias (North-West Spain). The project was promoted by the regional administration (Principado de Asturias), and its aim was to preserve in situ endangered native cultivars selected by local growers, and to protect the associated landscape, ethnographic and cultural values. In many cases, the chestnut orchards show a noticeable abandonment process, so the conservation efforts involved actions directed to recover the functionality of the systems. To do so, traditional knowledge was combined with modern techniques for operations like reclamation of trees (selection, pruning, grafting, shaping); conservation and maintenance of the orchard (shrub clearing, removal of ill trees); and the reconstruction of traditional stone structures (corros) used for chestnut fruit storage. In addition, efforts were made in the dissemination of knowledge regarding the project among the communities. Chestnut orchards are interesting examples of SEPLS, as they are normally forests cultivated and managed by local owners, who benefit from a range of goods and services, including chestnut fruits, wood, and agro-forestry grazing areas. Their strategic position in the landscape often allows for local climate regulation, erosion protection and water purification. Their structural and functional characteristics host high levels of biodiversity, and are important for the conservation of endangered species like the brown bear (Ursus arctos Linn.). Consequently, recovery actions for maintaining the structure and function of chestnut orchards play an important role in the scope of OECMs.
Area-based conservation; chestnut orchards; Social-Ecological Production Landscapes and Seascapes (SEPLS); rural development
Díaz-Varela, Emilio R., University of Santiago de Compostela; Álvarez-Álvarez, Pedro, Universidad de Oviedo; Roces-Díaz, José V., Universidad de Oviedo/Swansea University; Rodríguez-Morales, Beatriz., University of Santiago de Compostela
The summary sheet for this case study is available here.
Figure 1. Map of the country and case study region
Figure 2. Land use and land cover map of case study site. Caranda Baxu village, North-West Spain.
Figure 3. Land use and land cover map of case study site. Villamorei village, North-West Spain.
The role of SEPLS in area-based conservation measures
Socio-Ecological Production Landscapes and Seascapes (SEPLS) frequently illustrate the capacity to establish synergies among the enhancement of ecosystem services, conservation of biodiversity, multi-stakeholder socio-economic development, multifunctional use of land within the carrying capacity and resilience of the environment, as well as the preservation of traditional knowledge, local traditions and culture (eds. Belàir et al. 2010; Okayasu & Matsumoto 2013). This capacity reveals the potential of SEPLS to be an integrated part of efforts oriented towards biodiversity conservation. In this sense, Aichi Biodiversity Target 11, established by the Convention on Biological Diversity (CBD) to be attained by 2020, states: “By 2020, at least 17 per cent of terrestrial and inland water areas and 10 per cent of coastal and marine areas, especially areas of particular importance for biodiversity and ecosystem services, are conserved through effectively and equitably managed, ecologically representative and well-connected systems of protected areas and other effective area-based conservation measures, and integrated into the wider landscape and seascape”. While the role of protected areas formally defined by different levels of administration is clear, discussions regarding the role of “other effective area-based conservation measures” (OECMs) are still taking place. The inclusion of the latter was an effort to acknowledge the contribution of areas not legally designated as protected areas to effective conservation (Laffoley et al. 2017). Further developments of the concept were recognized to help to avoid overlooking “the diversity of ways of conserving and sustainable use of biodiversity, including by Indigenous peoples and local communities” (McKinnon et al. 2015). This underlines the importance of acknowledging diversity in approaches for conservation and sustainable use of biodiversity, and the integration of communities through local initiatives. Finally, the ongoing development of “guidelines for recognising and reporting Other Effective Area-Based Conservation Measures” (IUCN-WCPA 2018, p.16) provides a provisional definition of an OECM as “a geographically defined space, not recognised as a protected area, which is governed and managed over the long-term in ways that deliver the effective in-situ conservation of biodiversity, with associated ecosystem services and cultural and spiritual values”. SEPLS in many instances fit within this definition without being subjected to specific protection frameworks or measures, as they are sometimes difficult to clearly define as nature conservation entities. However, other measures related to enhancement of the socio-ecological system itself and the improvement of the rural environment, might provide the maintenance of practices that lead to conservation of biodiversity.
As an example of actions to be taken in SEPLS, which, not being directly related to conservation of biodiversity, can contribute to the management of OECMs, we present here a project for the recovery of abandoned sweet chestnut orchards in two public forests in the region of Asturias, North-West Spain. The project was promoted by the regional administration (Principado de Asturias). Project management was developed by a joint team led by the two authors from the Universities of Oviedo and Santiago de Compostela. Activities were carried out by a local environmental services company (Canastur). The stated aim of the project was to preserve in situ endangered genetic material (i.e., native cultivars selected by local growers), and to protect the high value landscape, as well as the ethnographic and cultural value of chestnut orchards. The project took place from 8 March 2011 to 15 March 2012. We explored how actions like those implemented by this project, even when not biodiversity-conservation oriented, could support the objectives of area-based, in-situ conservation of biodiversity by the maintenance of the rural systems supporting SEPLS – a representative criterion for OECM (IUCN-WCPA 2018).
This chapter will first introduce the main features and importance of sweet chestnut orchards and the geographical settings of the project. Then, we describe the activities oriented to the recovery of chestnut orchards and associated heritage. Finally, we discuss how and why this type of action can help to define OECM approaches for conservation of biodiversity.
Sweet chestnut forests and associated SEPLS in NW Spain
Sweet chestnut (Castanea sativa Mill.) forests cover an extension of more than 2.5 million hectares in Europe. Their distribution includes the Mediterranean, Atlantic, Central and Eastern areas (Conedera et al. 2004b, Conedera et al. 2016). Although the species is sensitive to severe cold, and its fructification dependent on summer warmth, in North-West Spain chestnuts are found in Mediterranean and Atlantic climates, rarely above 1200 m of altitude (Diaz Varela et al. 2009; Roces-Díaz et al. 2015). Since the18th century, chestnuts have decreased dramatically, particularly in low lands, due to the spread of ink disease (caused by Phytophtora cambivora and P. cinnamomi) and more recently chestnut blight (Cryphonectria parasitica). Together with changes in land use systems, these are the main causes of the species’ decline (Díaz-Varela et al. 2011). While the species is considered to be native to the Iberian Peninsula (Conedera et al. 2004a; Roces-Díaz et al. 2018b), its relevance as a cultivated species took form in the Medieval Ages (Conedera et al. 2004a). The traditional management of sweet chestnut adopted two different regimes (Conedera et al. 2001): a) Coppice, pure forests regenerated from adventitious or dormant buds; and b) Orchard, grafted trees organized in open stands, known as soutos, castañeros or castañeos in NW Spain. The main use of the former regime was for timber; the latter had a multifunctional use, constituting interesting examples of SEPLS. Normally cultivated and managed by neighbouring communities and/or individual private owners, they provide a number of goods and services. A major one is the provision of food: barely without silviculture, chestnut orchards produce yearly around 3,000 kg of high quality chestnut fruits per hectare, and up to 200 kg of Boletus edulis when mycorrhized (Sinde-Stompel 2015). But other services are also relevant, such as the production of high quality timber for construction (5 m2 per hectare), wood for heating and traditional tools, agro-forestry grazing areas, litter for manure or mulching and honey production (Conedera et al. 2001; Aumeeruddy-Thomas et al. 2012; Roces-Díaz et al. 2018a). In addition, they have been described as outstanding microtopes that contribute to local biodiversity, with a great variety of mushroom species, including some of high market value (Fernández de Ana Magán et al. 1998; Baptista et al. 2010; Sinde-Stompel 2015). Their strategic position in the landscape often allows for climatic regulation, erosion protection and water purification. Their structural and functional characteristics, together with their mosaic arrangement with other ecosystems, provide them with high levels of biodiversity (Gondard et al. 2006; Guitián et al. 2012; Zlatanov et al. 2013). The configuration of mature trees, with abundant hollows and cavities, is inhabited by many species of little mammals and forest birds (Rubio 2009; Zlatanov et al. 2013). In addition, chestnuts are important in the diet of animal species including roe deer (Capreolus capreolus Linn.), red deer (Cervus elaphus Linn), wild boar (Sus scrofa Linn.), and the brown bear (Ursus arctos Linn.) (Naves et al. 2006; Rodríguez et al. 2007), the latter threatened in Spain and an umbrella species for conservation in the area (Fernandez-Gil, 2013).
Chestnut orchards have suffered a process of abandonment and degradation since the middle of the 20th century, due to changes in socio-economic activities in rural areas. The process of abandonment (Roces-Diaz et al. 2018a; Fig. 4) of a fully functional chestnut agroforestry system (Type 1 in Fig. 1) can follow different pathways: passing through a transitional system of abandonment, becoming partially functional (Type 2) and eventually reaching an abandoned state (Type 3). From any of the former types, successional stages can lead, depending on site characteristics and the process itself, to a mixed forest dominated by C. sativa (Type 4) or by any other species (Type 5). The process of abandonment may affect the ecosystem with a decline in biodiversity, as well as with changes in the ecosystem services supply. From the balanced supply of the fully functional system, the abandonment process triggers a trend towards a slightly higher supply of regulation services, as well as some provisional ones (e.g. energy).
Figure 4. Abandonment and restoration pathways between the different types of Castanea sativa forests (left) and consequences for the supply of ecosystem services (right). Adapted from Roces-Diaz et al. 2018a.
This study was centred in two sweet chestnut orchards located in public forests and associated with the villages of Caranga Baxu and Villamorei. Caranga Baxu (43°13’8.42″N 6° 2’16.52″; 250m) has 32 inhabitants (Instituto Nacional de Estadística, 2017), and is one of the settlements of the Municipality of Proaza, in the Autonomous Community of Asturias (North-West Spain). Villamorei (43°12’59.57″N 5°28’5.95″O; 405m), with 81 inhabitants, (Instituto Nacional de Estadística, 2017) is located in the Municipality of Sobrescobiu, Asturias (see Fig. 1). Both settlements are in rural areas, and despite their relatively low altitudes, they can be considered as mountainous areas due to the complicated relief and their position within the Cantabrian Mountain range. Their marginal position, while characterised by the abandonment of the primary sector and an aged population, contributed to the conservation of some traditional agricultural practices. The landscape in these areas was shaped through centuries of interaction between societies and nature, eventually defining a multifunctional agricultural and forest mosaic of which chestnut orchards were a fundamental part (López-Merino et al. 2009; Pérez-Díaz et al. 2016)(see Fig.2 and 3).
Description of activities
While the chestnut orchards have suffered from the abandonment processes described in previous sections, there is still a valuable diversity of varietal genetic materials of the species, the preservation of which was one of the main objectives of the activities undertaken in the study areas. Such activities also aimed to contribute to the maintenance of the landscape, as well as the ethnographic and cultural values of the orchards. Techniques were applied to return the functionality of the systems (i.e., stability and fruit production) that had existed in the past, through a restoration process for orchards suffering the detrimental impacts of abandonment (See Fig. 4). Traditional knowledge was combined with modern techniques for operations like reclamation of trees (selection, pruning, grafting, shaping) and conservation and maintenance of the orchard (shrub clearing, removal of ill trees). Other actions were directed towards the cultural aspects of the orchard, like reconstruction of traditional stone structures (known as corros) used for chestnut fruit storage and conservation. In addition, specific efforts (e.g. placing informative boards in the area) were made for the dissemination of knowledge regarding the project among the community.
Recovery techniques applied on trees and orchards
The recovery of orchards involved four stages.
Felling of trees. One of the main principles for maintaining the functionality of an orchard is to recover the vitality and production capacity of both the whole orchard and the individual trees. To do so, it is important to select and maintain the grafted trees. In this stage, those trees not previously grafted were selected for a) being grafted; b) being kept for pollination; or c) being removed. The removal process used mechanical means—chainsaws for cutting and crane-implemented trucks to remove the spare materials (See Fig. 5). Due to the susceptibility of the species to fungal diseases, special care was taken to avoid infection with Cryphonectria parasitica and other species (e.g. disinfection of cutting tools and elimination of damaged materials), and damage to neighbouring trees.
Figure 5. Use of mechanical means to remove felled trees (Source: GIS-Forest 2012).
Pruning and removal of low sprouts. Pruning was executed in order to remove deadwood in the tree crowns, as well as to lower branch density and increase tree stability. This contributes to the improvement of fruit production and sanitary state of the tree. In addition, sprouts in the lower part of the trees were removed in order not to diminish the vitality of the tree (lower sprouts have the potential of exhausting the grafted tree). These operations were made using mechanical means, keeping the same disinfection protocols as those applied on the cutting tools(see Fig. 6).
Figure 6. Chestnut tree before (left) and after (right) pruning, in Caranga Baxu (Source: GIS-Forest 2012).
Sanitation of trunks using fire. This is a technique reclaimed from traditional knowledge in certain areas of the northwest Iberian Peninsula with chestnut orchards. Old cultivated chestnut trees tend to rot in the centre of their trunk, thus increasing their exposure to diseases. Fire was used to burn the rotten part for a few minutes, creating at the same time a protective layer of charcoal. Temperature is regulated by spraying water in order not to affect the living part of the tree(see Fig.7).
Figure 7. Fire used in sanitation of a tree’s trunk (Source: GIS-Forest 2012).
Grafting. Those trees selected for grafting in the first stage were cut at 1.5-1.8 meters to prepare them as rootstocks. Local cultivars were used for grafting: six in Caranga Baxu (with the local names of Seronda, Verdeta, Tixera, Picona, Moriña and Fanuca) and four in Villamorei (Valduna, Ramiega, Montesa and Sevillana). To preserve their genetic characteristics, stems were directly selected in each respective area to function as scions (i.e, the part of the graft that is inserted in the stem to produce fruit). Traditional techniques such as crown and cleft grafting were used in this stage (see Fig. 8).
Figure 8. Schemes for cleft (left) and crown (center) grafting (Source: Alvarez-Alvarez et al. 2000), and results of crown grafting in the field (right; source: GIS-Forest 2012).
Reconstruction of traditional structures
In the traditional management of chestnut orchards, circular structures made of stone were used for temporary in situ storage of chestnut fruits. Depending on the area, such structures were named corros, corripies, curripas, corripas, corras, cuerrias or xoxas. New approaches towards management, as well as new types of transport and storage means, have left these structures abandoned. Nevertheless, they have been restored in order to preserve the constructed heritage linked to traditional activities (see Fig. 9).
Figure 9. Reconstructed corro (Source: GIS-Forest 2012).
Another cultural aspect considered important in the area was the dissemination of knowledge regarding the project among both the local inhabitants and potential visitors. Informative boards showing the main activities, as well as the importance of chestnut orchards for the local ecology and economy, were placed in strategic locations(see Fig.10).
Figure 10. Content of one of the informative boards (Source: GIS-Forest 2012).
Results and discussion
Recovery of chestnut orchards
A total of 3.3 ha of chestnut orchards (1.3 ha in Caranga Baxu and 2 ha in Villamorei) were recovered using the techniques outlined in the previous sections. The total number of trees treated was 200 in Caranga Baxu and 130 in Villamorei(see Fig.11).
Figure 11. View of the orchard in Villamorei before (left) and after (right) the reclamation procedures (Source: GIS-Forest 2012).
While the main objectives of the project were recovery of the orchards, the preservation of genetic material, and the improvement of landscape quality and heritage features, an early ex-post assessment of the effect of the activities on productivity was made. The assessment consisted of a comparison of the total weight of chestnut fruit harvested in two 10x10m plots, one in the restored orchard of Caranga Baxu, and other in a nearby abandoned forest, at the same hour during two days of the harvest period (20 October and 7 November) in the same year as the execution of the project. The recovered plot showed 20% more production than the abandoned one. Despite the lack of inference validity of the assessment, the results are indicative of improvements made by project actions, and are consistent with studies in similar geographical sites (e.g. Martins et al. 2012).
Potential role of recovered chestnut orchards in biodiversity protection
As explained in the introduction, the objective of the project was the conservation, in two specific sites, of native cultivars of C. sativa, carried out through recovery of the structure of the orchards, under the assumption that the structure may involve functions that support landscape ethnographic and cultural values. As described for other examples of SEPLS (Okayasu & Matsumoto 2013), adequate management of chestnut orchards and plantations may potentially increase species richness (Gondard et al. 2001; Gondard et al. 2006; Martins et al. 2012), being consequently higher than in abandoned orchards. Consequently, the recovery of chestnut orchards may be interpreted as a multi-purpose measure, which contributes to the enhancement of biodiversity levels in the rural landscape, as well as the increase of different ecosystem services, including those that may be of high socio-economic relevance. As “traditional management systems that maintain high levels of associated biodiversity” (IUCN-WCPA 2018), these areas can be the subjects of strategies of “secondary conservation” in the perspective of OECMs, which is achieved through the active conservation of an area where biodiversity outcomes are a secondary management objective (IUCN-WCPA 2018).
In this context, it is important not to neglect that, in Aichi Biodiversity Target 11, both protected areas and OECMs are explicitly considered as parts of “well connected systems”. In this sense, an important contribution of SEPLS in general, and particularly of the one analysed in this study case, is their function as elements that increase connectivity, due to their spatial arrangement and strategic position to act as stepping stones or corridors for diverse animal and plant species. Thus, from a spatial point of view, the reclaimed chestnut orchards function as linkages as well as transition zones between protected areas and the immediate rural environment. For the case of Caranga Baxu, Figure 12 shows the potential connectivity function of the recovered orchard in the area, which can be complemented in other areas of the chestnut forest if similar actions are implemented. The recovered area can thus also be a linkage between a Natural Park, a Natural Monument and a Biosphere Reserve. Also, the area is important for brown bear populations, so recovered orchards could be beneficial to this species, taking into account the low risk of human-bear interactions (Penteriani et al. 2016), if potential damage to different productive activities of the community like livestock, fruit and honey production (Pollo 2006) is appropriately addressed.
Potential role of recovered chestnut orchards in biodiversity protection
Figure 12. Relative position of the recovered orchard in Caranga Baxu (red circle) with respect to protected areas (Natural Parks and Monuments, Bird Special Protection Areas, or Biosphere Reserves). Chestnut forest typologies show where the species is dominant (first), or is the second or third species in abundance. Potential connectivity pathways show the possible function of recovered orchards as ecological linkages.
In Villamorei the situation and potential approach is slightly different. Figure 13 shows how the area is located well inside a Natural Park, coincident with a Biosphere Reserve and a Bird Special Protection Area. In this case, the recovery of the area could complement the efforts developed inside the conservation areas, which can be especially relevant in transition or buffer zones that support nearby core areas with biodiversity spots while low-intensity human activities are taking place.
Figure 13. Relative position of the recovered orchard in Villamorei (red circle) with respect to protected areas (Natural Parks and Monuments, Bird Special Protection Areas, or Biosphere Reserves). Chestnut forest typologies show where the species is dominant (first), or is the second or third species in abundance.
Involvement of local communities and integration in the governance system
The initial idea for the development of the project arose out of the interest shown by the local population to put to use the abandoned chestnut orchards. Motivations included both the recovery of the productive capacity of the orchards for chestnut fruits, as well as heritage preservation. For instance, many among the older inhabitants still named the individual trees by the households owning the access rights to them, which is still customary following the common law. Nevertheless, as explained previously, the orchards are classified as public utility forests, meaning that they are municipal properties, managed by the regional government. In times prior to the development of the project, the local communities tried to restore activity in the chestnut orchards, but were unsuccessful. At their request, the municipalities made a petition to the regional administration for their intervention in the recovery of the chestnut orchards. This, together with the political influence of a political party that supports the initiative, and the positive involvement of the forestry technicians, helped to stir up the interest of the administration in the project. As a result, and as explained in sections 1.1 and 2.1, the project was promoted by the local administration, which assumed the supervision and financing roles. It was managed by university experts in the field who designed the combination of traditional and modern techniques to undertake the project. Likewise, the project was executed by a local company, which carried out the technical implementation.
As a result of project execution, people from the local communities started to collect the chestnut fruits again, and reported improvement in the orchards’ production capacity. In addition, livestock grazing, especially with sheep, goats and pigs, also started in Villamorei immediately following the recovery of the orchard. The recovery is also seen as compatible with other activities of local importance, such as wild boar hunting. Altogether, this is potential evidence of the improvement in the multifunctional aspects of the area.
Communities also responded actively to threats to recovered orchards, for instance with their involvement in firefighting on some occasions when wildfires extended from nearby scrublands and afforested areas. Local newspapers reported the feelings of loss and sadness of the local population after the fires (Arias 2015). Also, local as well as regional administrations have promoted the chestnut orchards in tourist routes and organized educative visits. The local company in charge of the execution, in collaboration with the University of Oviedo, developed a webpage entitled, “recurso castaño” (2011), where the works carried out are shown in video format, for extension and dissemination purposes.
Importance of the rural policy context
Inclusion of the recovery techniques of chestnut orchards into biodiversity conservation schemes should consider the evolution of and new trends in socio-ecological systems in an integrative manner. Productive chestnut orchards have experienced many changes during the last decades, and their resilience and permanence in time will depend on the dynamic exchange between socio-ecological legacies and innovations (Aumeeruddy-Thomas et al. 2012). This could take form of integration of traditional knowledge and modern technologies for the recovery of the forest structure, like in the cases shown in this work, as well as the acknowledgement of new functions, including the conservation of important species and processes in the landscape. In this sense, the management of chestnut orchards from a multifunctional perspective has the potential to create and perpetuate sustainable and resilient socio-ecological systems, promoting economic diversification, biodiversity, and environmental quality (Martins et al. 2011).
Taking all this into account, secondary conservation strategies in the scope of OECMs could benefit from policy context not directly related to biodiversity conservation. For instance, the Rural Development Policy in the European Union is regulated for the period 2014-2020 through the Regulation (EU) nº 1305/2013 of the European Parliament and of the Council (2013). In its Article 5, six “Union priorities for rural development” are defined, including priority 4, “restoring, preserving and enhancing ecosystems related to agriculture and forestry”. Member states and their regions develop Rural Development Programs in order to target the different priorities. In the Regional Programme for Rural Development of Asturias (2017), the region where the study sites are located, the importance of chestnut cultivation for reducing climate change effects is acknowledged, and there are specific subsidies designed for the establishment and maintenance of agroforestry systems, with specific mention of chestnut trees as a potential species. In this framework, projects similar to the one presented here could be developed by local owners and communities for recovery of chestnut areas, enhancing the capacity of this particular socio-ecological production system for multiple functions, including the conservation of biodiversity.
Difficulties and future challenges in implementation
Besides the difficulties associated with the restoration process itself (e.g., compilation of previous research, technology transfer, stakeholder management and communications), one of the main challenges found in the project’s implementation was, as commented in previous sections, the lack of institutional interest and involvement at some levels of public administration. Thus, the connection between bottom-up interest in the project and the top-down support needed for carrying it out should be guaranteed in future similar projects. Nevertheless, on a side note, it should be pointed out that at least six communities contacted the local company (due to the acquired knowledge of recovery techniques) to carry out similar projects without the intermediation of administrative bodies. This underlines the importance of technology transfer, and the interest of pilot studies in the informal adoption of management practices.
In addition, a series of generic, territorial problems were identified that may hinder the continuity and sustainability of the projects. These include: population aging (and the subsequent lack of generational replacement in rural areas); the occurrence of forest fires (that, originating in neighbouring scrublands or afforested areas, may spread into the orchards); and genetic contamination by clones resistant to fungal diseases. Consequently, rural development initiatives, forest prevention and management practices, as well as forest management practices that are non-dependent on clone varieties, should be integrated into the restoration projects.
Chestnut orchards provide a number of environmental functions, genetic resources, and economic and socio-cultural benefits. Framing all these contributions as ecosystem services allows for linking ecosystems with human welfare, ecological value, biodiversity, and the acknowledgement of the important role of these systems in rural development and the preservation of traditional landscapes and culture. Consequently, the recovery of chestnut orchards integrating traditional knowledge and modern technologies may be one of the possible strategies for secondary conservation of biodiversity from the perspective of OECMs, using SEPLS as a reference area, and benefitting from potential synergies with other non-conservation policies and actions like those related to rural planning and development.
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