It's a keeper: Valuing the carbon storage service of Agroforestry ecosystems in the context of CAP Eco-Schemes
Introduction
Agricultural and agroforestry landscapes across Europe are shaped by complex interactions between the physical environment, socioeconomic factors, and policy settings, among which the Common Agricultural Policy (CAP) plays a vital role (van Zanten et al., 2014, Kristensen, 2016, Ustaoglu and Williams, 2017). In some European countries, including Portugal, CAP incentives are critical for preserving the Montado - an internationally acknowledged landscape with high conservation and socioeconomic value (Bugalho et al., 2016, Campos et al., 2018).
Montados (known in Spain as Dehesas) are agro-silvopastoral systems with a savanna-like land cover pattern that provide multiple benefits to society (Pinto-Correia et al., 2011, Marta-Pedroso et al., 2014a, den Herder et al., 2017). In Portugal, Montado is mainly characterized by the presence of sparse Quercus spp. stands (particularly Quercus suber and Quercus rotundifolia), with grassland-covered understories with extensive grazing. It has been established that Montado landscapes provide a wide range of benefits, from carbon sequestration and soil erosion control to improving nutrient and water cycling, promoting biodiversity, increasing agricultural productivity and offering other socioeconomic benefits (Marta-Pedroso et al., 2018, Pinto-Correia et al., 2018, Brown et al., 2018, Kay et al., 2019a). These benefits can be referred to as Ecosystem Services (ES), a concept that refers to the benefits humans derive from ecosystems (MA 2005), bridging ecology, economics and the other social sciences (Burkhard et al., 2010).
However, the multiple ES provided by Montado landscapes require sustainable management practices that can only be implemented under proper financial incentives (Bugalho et al., 2011, Acosta et al., 2014). In the absence of such incentives, Montado landscapes are most likely doomed to either abandonment (low maintenance management practices) or intensification (increasing grazing pressure) to increase profitability. In fact, national statistics indicate around 148 thousand hectares of cork- and holm-oak Montado converted into either grasslands or shrublands over the last 25 years (ICNF, 2019).
On the one hand, the abandonment of human intervention in Montado will likely result in landscapes dominated by unmanaged shrubland, with prevailing shrub encroachment of mostly native Cystus spp., which poses a significant threat in terms of wildfire risk (Nunes et al., 2019). On the other hand, pasture intensification may compromise the natural regeneration of Quercus spp., which leads to grassland-dominated landscapes and decreasing soil quality and composition (Guerra et al., 2016, Torralba et al., 2016, Rubio-Delgado et al., 2018). As a result, pasture intensification potentially compromises carbon sequestration (Concostrina‐Zubiri et al., 2017, Essen et al., 2019) and impacts biodiversity and habitat structure (Moreno et al., 2018, Pinto-Correia et al., 2018).
Of all the potential ES provided by an agroforestry system, its capacity to store carbon has been long established (Schroeder, 1994, Marta-Pedroso et al., 2014b) and is receiving increasing attention (Kay et al., 2019a). The various biotic components present in the system (trees, grasses, soil) sequester and/or store significant amounts of carbon, thus composing a landscape with paramount potential to contribute to climate change mitigation, especially in Mediterranean landscapes (Kay et al., 2019b).
Greenhouse gas emissions are a leading cause of climate change, and possible climate mitigation mechanisms generally range from increasing carbon sequestration to reducing emission sources (Fawzy et al., 2020). It has been suggested that socioeconomic issues hinder such mechanisms, as emitting agents fail to support the social cost of their carbon emissions and sequestration agents are not rewarded for the carbon sequestration benefits they provide - the so-called externalities (Price et al., 2007). Given this market failure, internalizing carbon emission and sequestration calls for bringing these costs and benefits to markets.
Until now, farmers maintaining sustainable agroforestry systems in Europe are only compensated for foregone benefits (incurred costs) through the AECMs in CAP (Agri-Environment-Climate Measures, Pillar 2),2 without acknowledging the concomitant ES provided by the supported management. The next funding period of CAP after 2020 (CAP2020+), however, addresses this issue by integrating a Payment for Ecosystem Services scheme (PES scheme) through direct payments to farmers in Pillar 1, the so-called Eco-Schemes (Lampkin et al., 2020).
Despite the potential of agroforestry systems to store carbon, inconsistent methodologies and a lack of quantitative reviews have held back the implementation of reward schemes based on carbon (Feliciano et al., 2018). Carbon storage is a stock externality of agroforestry systems, as farmers provide a benefit for which they are unrewarded under current CAP instruments or through the market. Therefore, the objectives of this work are (1) assessing changes in net carbon flow resulting from either abandonment or grazing intensification in Portuguese Montado landscapes, and (2) assigning a value to changes in net carbon flow targeting the design of CAP2020+ Eco-Schemes. To our best knowledge, this work is the first attempt at valuing carbon sequestration in Portuguese agroforestry systems in the context of the Eco-Schemes recently introduced in CAP2020+.
Section snippets
Material & methods
In this work, we have focused on Montado agroforestry systems in Portugal, which comprise sparsely wooded cork-oak (Quercus suber) and holm-oak (Quercus rotundifolia) landscapes with grassland-dominated understories.
We aimed to assess carbon sequestration in Montado given three different land-use change scenarios using biomass equations and accounting for fire risk. Our approach focused on identifying carbon stock changes (hence net carbon flow) within each scenario over a fixed period of time.
Biophysical assessment
Net carbon flow (in tCO2eq.ha-1.year-1) for scenarios A, B, and C, given three different conversion periods (20, 70, or 120 years), have been estimated for both cork and holm oak-dominated Montado (Tables 3 and 4, respectively). Overall, our results indicate that scenarios with land-use change (scenarios A and C) are associated with carbon emissions (negative flow) in all conversion periods considered. In contrast, the scenario with land-use conservation (scenario B) is associated with carbon
Biophysical assessment
In the absence of financial incentives, profit-maximizing farmers in Portugal are usually faced with either abandoning (scenario A) or intensifying grazing activity (scenario C) in Montado systems.
Rural abandonment in Portugal is a widely studied phenomenon (Beilin et al., 2014, Sil et al., 2019), with reports of increasing fragmentation in agroforestry landscapes and increasing shrubland area due to abandonment (Costa et al., 2014). Though there is evidence to suggest that land-use abandonment
Conclusions
In Portugal, the sustainable management of agroforestry Montado systems currently relies on compensations for foregone benefits under Pillar 2 of the European Common Agricultural Policy (CAP).
In this study, we have shown that, in the long haul, abandonment or grazing intensification of Montado ecosystems in Portugal are scenarios that result in negative changes in net carbon flow. Our estimates for the 120-year conversion period indicate annual carbon emissions up to 1.5tCO2eq/ha for the
CRediT authorship contribution statement
Lia Laporta: Conceptualization, Methodology, Formal analysis, Investigation, Writing – original draft, Writing – review & editing. Tiago Domingos: Conceptualization, Methodology, Writing – review & editing, Supervision. Cristina Marta-Pedroso: Conceptualization, Methodology, Writing − review & editing, Supervision.
Declarations of interest
The authors declare that they have no conflict of interest.
Acknowledgements
This work has been partially supported by FCT/MCTES (PIDDAC) throughproject UIDB/EEA/50009/2020 and by the Portuguese Rural Development Programmefor 2020 (PDR2020), intervention area 3 (Technical Assistance), under contract 20.2.3/2018, through project ECOPOL "Internalizing the functionalnarrative of Montado in the formulation, monitoring, and evaluation ofrural development policies". L.L. work was supported by the Portuguese Foundation for Science and Technology (FCT) through the PhD grant
References (90)
- et al.
Long-term sustainability of cork oak agro-forests in the Iberian Peninsula: a model-based approach aimed at supporting the best management options for the montado conservation
Ecol. Model.
(2017) - et al.
Payments by modelled results: a novel design for agri-environmental schemes
Land Use Policy
(2021) - et al.
Analyzing how drivers of agricultural land abandonment affect biodiversity and cultural landscapes using case studies from Scandinavia, Iberia and Oceania
Land Use Policy
(2014) - et al.
Ecosystem services – bridging ecology, economy and social sciences
Ecol. Complex.
(2010) - et al.
Result-oriented agri-environmental schemes in Europe and their potential for promoting behavioural change
Land Use Policy
(2013) - et al.
Assessing impacts of future climate change on extreme fire weather and pyro-regions in Iberian Peninsula
Sci. Total Environ.
(2021) - et al.
Total income and ecosystem service sustainability index: accounting applications to holm oak dehesa case study in Andalusia-Spain
Land Use Policy
(2020) - et al.
Environmental incomes: refined standard and extended accounts applied to cork oak open woodlands in Andalusia, Spain
Ecol. Indic.
(2020) - et al.
Fragmentation patterns of evergreen oak woodlands in Southwestern Iberia: Identifying key spatial indicators
J. Environ. Manag.
(2014) - et al.
Current extent and stratification of agroforestry in the European Union
Agric., Ecosyst. Environ.
(2017)
A review of the combination among global change factors in forests, shrublands and pastures of the Mediterranean Region: Beyond drought effects
Glob. Planet. Change
Socio-economic valuation of abandonment and intensification of Alpine agroecosystems and associated ecosystem services
Land Use Policy
A systematic map of ecosystem services assessments around European agroforestry
Ecol. Indic.
Which agroforestry options give the greatest soil and above ground carbon benefits in different world regions?
Agric., Ecosyst. Environ.
Agroforestry is paying off – economic evaluation of ecosystem services in European landscapes with and without agroforestry systems
Ecosyst. Serv.
Agroforestry creates carbon sinks whilst enhancing the environment in agricultural landscapes in Europe
Land Use Policy
Agriculture and landscape interaction—landowners’ decision-making and drivers of land use change in rural Europe
Land Use Policy
Grazing improves habitat suitability for many ground foraging birds in Mediterranean wooded grasslands
Agric., Ecosyst. Environ.
Agroforestry in Europe: a land management policy tool to combat climate change
Land Use Policy
Local topographic and edaphic factors largely predict shrub encroachment in Mediterranean drylands
Sci. Total Environ.
Effects of grazing abandonment on soil multifunctionality: the role of plant functional traits
Agric., Ecosyst. Environ.
Progress in identifying high nature value montados: impacts of grazing on hardwood rangeland biodiversity
Rangel. Ecol. Manag.
Estimation of soil erosion rates in dehesas using the inflection point of holm oaks
CATENA
Farmland abandonment decreases the fire regulation capacity and the fire protection ecosystem service in mountain landscapes
Ecosyst. Serv.
Different approaches to model future burnt area in the Iberian Peninsula
Agricultural and Forest Meteorology
Soil organic matter dynamics in Portuguese natural and sown rainfed grasslands
Ecol. Model.
A conceptual framework for the analysis of engineered biodiverse pastures
Ecol. Eng.
Do European agroforestry systems enhance biodiversity and ecosystem services? A meta-analysis
Agric., Ecosyst. Environ.
Carbon pricing and deep decarbonization
Energy Policy
Soil carbon changes after establishing woodland and agroforestry trees in a grazed pasture
Geoderma
An agent-based assessment of land use and ecosystem changes in traditional agricultural landscape of Portugal
Intell. Inf. Manag.
Portuguese National Inventory Report on Greenhouse Gases, 1990 – 2012. Submitted Under the United Nations Framework Convention on Climate Change and The Kyoto Protocol
Carbon and nitrogen balances for six shrublands across Europe
Evidence for the impacts of agroforestry on agricultural productivity, ecosystem services, and human well-being in high-income countries: a systematic map protocol
Environ. Evid.
Mediterranean cork oak savannas require human use to sustain biodiversity and ecosystem services
Front. Ecol. Environ.
Using the high conservation value forest concept and Pareto optimization to identify areas maximizing biodiversity and ecosystem services in cork oak landscapes
Agrofor. Syst.
Environmental income of livestock grazing on privately-owned silvopastoral farms in Andalusia, Spain
Land Degrad. Dev.
Effects of land abandonment on plant litter decomposition in a Montado system: relation to litter chemistry and community functional parameters
Plant Soil
Grazing or not grazing: implications for ecosystem services provided by biocrusts in Mediterranean Cork Oak Woodlands
Land Degrad. Dev.
Agroforestry for soil health
Agrofor. Syst.
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