552 research outputs found

    Environment Workshops 2013. Oak forests coping with global change: ecology and management

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    Congreso celebrado del 30 de septiembre-2 de octubre 2013, en Baeza (JaĂ©n), España.The genus Quercus has about 500 species distributed throughout the Northern Hemisphere. Oak forests and woodlands are very abundant in the Mediterranean region and are vital providing a variety of ecosystem services. They provide with raw materials like cork, wood and fuel, and fodder for wild and domestic animals. The silvopastoral system known as “dehesa” provides habitats for wild animals and contributes to a higher biodiversity at the landscape scale. Oak trees provide a climate regulating service by their capacity to sequester carbon and therefore to mitigate the effects of climatic change. There is an increasing demand for cultural services provided by oak woodlands, mainly for recreation, ecotourism, and to enjoy their aesthetic and spiritual values. However, Global Change is affecting negatively oak forests and therefore diminishing their ecosystem services and in consequence human wellbeing. Main drivers are: land use change, introduction of exotic pathogens, air and soil pollution deteriorating oak health, and climatic change, in particular the reduction of rainfall. The aims of the workshop are to analyse the vulnerability and resilience of Quercus species coping with Global Change; to review the main ecological processes related with the regeneration of oaks and how they influence the recruitment and persistence of oak forests; to discuss the different management options for coping with the decline of oak forests and to assure their sustainability, showing case studies from Spain, Portugal and Mexico.Peer reviewe

    A Methodology for Automatic Identification of Units with Ecological Significance in Dehesa Ecosystems

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    The dehesa is an anthropic complex ecosystem typical of some areas of Spain and Portugal, with a key role in soil and biodiversity conservation and in the search for a balance between production, conservation and ecosystem services. For this reason, it is essential to have tools that allow its characterization, as well as to monitor and support decision-making to improve its sustainability. A multipurpose and scalable tool has been developed and validated, which combines several low-cost technologies, computer vision methods and RGB aerial orthophotographs using open data sources and which allows for automated agroforestry inventories, identifying and quantifying units with important ecological significance such as: trees, groups of trees, ecosystem corridors, regenerated areas and sheets of water. The development has been carried out from images of the national aerial photogrammetry plan of Spain belonging to 32 dehesa farms, representative of the existing variability in terms of density of trees, shrub species and the presence of other ecological elements. First, the process of obtaining and identifying areas of interest was automated using WMS services and shapefile metadata. Then, image analysis techniques were used to detect the different ecological units. Finally, a classification was developed according to the OBIA approach, which stores the results in standardized files for Geographic Information Systems. The results show that a stable solution has been achieved for the automatic and accurate identification of ecological units in dehesa territories. The scalability and generalization to all the dehesa territories, as well as the possibility of segmenting the area occupied by trees and other ecological units opens up a great opportunity to improve the construction of models for interpreting satellite images

    Comparative Sustainability Assessment of Extensive Beef Cattle Farms

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    This chapter analyzes the sustainability of beef cattle systems of the Spanish Rangelands known as “Dehesas”. These are traditional systems of the Iberian Peninsula where native herbaceous vegetation and evergreen species of Quercus provide the basis for extensive livestock farms. These systems are considered as outstanding High Nature Value (HNV) farming systems and the most extensive agroforestry systems in Europe according to CORINE Land Cover. Beef farms in this area show low stocking rates and a small dependence on foodstuff purchases.However, certain changes have occurred in the last decadesdue to the Common Agricultural Policy (CAP). On the one hand, some farms have become more intensified, as a way to maximize the revenues from the CAP subsidies. On the other hand, many farms have turned to organic production, trying to take advantage both of new subsidies and of new market trends. In this regard, the organic livestock farming model is gaining weight as an option for sustainable production since, according to various authors, these systems have advantages over conventional and intensive systems. In fact, organic production in the area has increased substantially in recent years due to several factors, such as the growing interest of the EU towards preserving sensitive ecosystems, the potential role of organic production in the development of rural areas and the growing consumers’ demand for safer and higher quality foods produced under ethical and environmental standards. In this study, we carried out a comparative assessment of the sustainability of different conventional and organic beef production systems located in dehesa rangelands. The systems analyzed were classified as follows. (i) non-organic farms (Conventional); (ii) organic farms that sold calves at weaning age as conventional ones (Organic 1); (iii) organic farms that fattened and sold their calves as organic (Organic 2). An adaptation of the MESMIS multicriteria framework was applied to calculate sustainability indices for each system. The results showed that the Organic 2 farms scored highest on most of the attributes of sustainability, as well as on the environmental and economic dimensions of sustainability. Thus, they were the most sustainable system (66.55%), followed by the Organic 1 (61.04%) and Conventional ones (56.89%). Despite Organic 2 was the most sustainable system, its implementation is complex due to both the high costs of organic inputs and the weak demand for organic beef. The results also showed that all three types of systems need to improve in certain aspects that are crucial in the current and future context of the livestock sector. These aspects are: reducing the dependence on external feed, implementing more environmentally friendly farming practices, and farm diversification

    LINHE Project: Development of new protocols for the integration of digital cameras and LiDAR, NIR and Hyperspectral sensors.

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    The LINHE project aims to develop applications for forest management based on the combined use of LiDAR data, images from spaceborne (multi and hyperspectral) and airborne sensors (panchromatic, colour, near infrared), and NIR field data from a portable sensor. The integration of the different types of data should be performed in a rapid, intuitive, cost-effective and dynamic way. In order to achieve this objective, new algorithms were developed and existing ones were tested, for the correlation of data collected in the field and those gathered by the different sensors. Specific software (LINHE prototype viewer) was developed to support data gathering and consultations, and it was tested in three different forest ecosystems, so as to validate the tool for forest management purposes. The optimisation of the synergic capabilities derived from the combined use of the different sensors will allow the enhancement of their efficiency and provide accurate information for operational forestry

    Spatial distribution of the soil carbon pool in a Holm oak dehesa in Spain

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    Aims Dehesas are agroforestry systems characterized by scattered trees among pastures, crops and/or fallows. A study at a Spanish dehesa has been carried out to estimate the spatial distribution of the soil organic carbon stock and to assess the influence of the tree cover. Methods The soil organic carbon stock was estimated from the five uppermost cm of themineral soil with high spatial resolution at two plots with different grazing intensities. The Universal Kriging technique was used to assess the spatial distribution of the soil organic carbon stocks, using tree coverage within a buffering area as an auxiliary variable. Results A significant positive correlation between tree presence and soil organic carbon stocks up to distances of around 8 m from the trees was found. The tree crown cover within a buffer up to a distance similar to the crown radius around the point absorbed 30 % of the variance in the model for both grazing intensities, but residual variance showed stronger spatial autocorrelation under regular grazing conditions. Conclusions Tree cover increases soil organic carbon stocks, and can be satisfactorily estimated by means of crown parameters. However, other factors are involved in the spatial pattern of the soil organic carbon distribution. Livestock plays an interactive role together with tree presence in soil organic carbon distribution

    The Contribution of Organic Livestock to Sustainable Rural Development in Sensitive Areas

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    Organic production may contribute positively to rural development. However, there is a gap of knowledge with regard to the livestock sector that the present work is aimed at filling by means of a multidisciplinary and participatory approach. The results suggest that ‘fully organic’ holdings (organic farms that sell products as organic) have the highest potential to contribute to the rural development in the area under study. Nevertheless, its implementation requires higher levels of education and implies higher costs. Due to these difficulties, public subsidies should support such production systems. Moreover, systems with low productivity but high environmental services should be also supported, such as those extensive (either conventional or organic)

    Multifunctional natural forest silviculture economics revised: Challenges in meeting landowners’ and society’s wants: A review

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    Aim of study: This paper objective focuses on the contribution of multifunctional natural forest silviculture, incorporating both private and public product managements, to forest and woodland economics. Area of study: Spain and California (USA) Material and methods: This conceptual article has developed a critical revision of the existing literature on the main economic issues for the multifunctional natural forest silviculture in the last decades. Main results: Multifunctional natural silviculture has secular roots as a local practice, but as a science of the natural environment applied to the economic management of forest lands it is still in the process of maturation. Timber silviculture remains the central concern of forest economics investment in scientific publications. By contrast, silvicultural modeling of the natural growth of firewood, browse and other non-timber forest products from trees and shrubs receives scant attention in scientific journals. Even rarer are publications on multifunctional natural silviculture for forest and woodland managements, including environmental services geared to people’s active and passive consumption. Under this umbrella, private environmental self-consumption is represented by the amenities enjoyed by private non-industrial landowners. As for environmental public products, the most relevant are carbon, water, mushrooms, recreation, landscape and threatened biodiversity. Research highlights: This paper is a good example for the conceptual research on forestry techniques and economic concepts applied to multifunctional silviculture in Mediterranean areas of Spain and California. The combination of technical knowledge and private and public economic behaviors definitively contributes to the multifunctional management of natural forest systems

    The effectiveness of policies promoting sustainable permanent grasslands across five European countries (representing five biogeographic regions): mapping, understanding, and key stakeholder perceptions

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    The purpose of this report is to identify, map, and evaluate the most relevant European policies seen to influence permanent grassland (PG) management. To accomplish this, an interdisciplinary, crossnational team from the UK, Switzerland, Spain, Czech Republic, and Sweden reviewed over 50 in-depth policy frameworks. With direction from expert stakeholders and a review of the policy landscape, we identified the most relevant policy instruments influencing PGs across five different biogeographic regions in Europe (Alpine, Atlantic, Boreal, Continental, and Mediterranean). The mapping of each country’s policy mix was guided inter-alia by a ‘cascade framework’ to illustrate the entry points, intermediary actors, mechanisms and pathways through which policies deliver their intended effects on PGs. This entailed an in-depth analysis of publicly available government sources documenting the aims, objectives, targets, monitoring systems, outputs and outcomes of each policy instrument. In total, 24 policies were mapped using 50 different criteria, with 15 of the policies unique to the case study countries. This resulted in an extensive excel database of over 3400 unique cells containing rich qualitative data. The excel data were coded in a consistent manner across the country teams so that they could be compared, synthesized, and used to identify patterns in the policy mix and logic of intervention. We show, for instance, that across Europe, the dominant policy logic uses regulations and incentives to influence farmer adoption of desired landscape compositions. This directly influences, but does not guarantee, the range of ecosystem services (ES) that are possible from the landscape. At the same time, we discovered a lack of policies targeting consumer demand for PG ecosystem services and only a few designed to drive sustainable PG management by directly promoting the value of PGs with beneficiaries. To complement the policy mapping, stakeholders’ assessed the perceived effectiveness of the policy mix in each country. This evaluation included over 50 interviews with key stakeholders across Europe representing government, academia, farmers, and special interests, and covered perceptions of democracy, legitimacy, relevance, efficiency and impact in relation to the effectiveness of policies relevant to the management of PG. Our findings reveal generally positive perceptions of grassland policy effectiveness across Europe, with special interest groups being the least positive and governments the most. The in-depth country case studies reveal striking similarities, as well as differences between countries and stakeholder groups, which are illustrative of the problems, challenges, and barriers confronting policy effectiveness. We conclude this report by offering insights and policy implications. In particular, we suggest that the following four points are taken into consideration to improve the PG policy landscape: 1) Reduce complexity and administrative burden to make policies more understandable and accessible. 2) Require stakeholder involvement when developing strategic plans and assessing policy. 3) Encourage consideration of trade-offs between PG management and ES delivery, by designing policies to explicitly target the interaction between landscape structures and ES (or target them in parallel). 4) Encourage a balance of policy logic, by moving away from targeting farmers with regulation or subsidies to manage the landscape towards targeting consumer demand for ES (through information) and the value of ES (such as direct payments for regulating and cultural services)
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