Abstract:Higher biodiversity leads to more productive ecosystems which, in turn, supports more biodiversity. Ongoing global changes affect ecosystem productivity and, therefore, are expected to affect productivity-biodiversity relationships. However, the magnitude of these relationships may be affected by baseline biodiversity and its lifeforms. Cork oak (Quercus suber) woodlands are a highly biodiverse Mediterranean ecosystem managed for cork extraction; as a result of this management cork oak woodlands may have both tree and shrub canopies, just tree and just shrub canopies, and just grasslands. Trees, shrubs, and grasses may respond differently to climatic variables and their combination may, therefore, affect measurements of productivity and the resulting productivity-biodiversity relationships. Here, we asked whether the relationship between productivity and climate is affected by the responses of trees, shrubs, and grasses in cork oak woodlands in Southern Portugal. To answer this question, we linked a 15-year time series of Enhanced Vegetation Index (EVI) derived from Landsat satellites to micrometeorological data to assess the relationship between trends in EVI and climate. Between 2000 and 2013 we observed an overall decrease in EVI. However, EVI increased over cork oaks and decreased over shrublands. EVI trends were strongly positively related to changes in relative humidity and negatively related to temperature. The intra-annual EVI cycle of grasslands and sparse cork oak woodland without understorey (savannah-like ecosystem) had higher variation than the other land-cover types. These results suggest that oaks and shrubs have different responses to changes in water availability, which can be either related to oak physiology, to oaks being either more resilient or having lagged responses to changes in climate, or to the fact that shrublands start senesce earlier than oaks. Our results also suggest that in the future EVI could improve because the rate of increase in minimum EVI is greater than the rate of decrease in maximum EVI, and that this is contingent on management of the shrub understorey as it affects the rate of decrease in maximum EVI. This will be the challenge for the persistence of cork oak woodlands, their associated biodiversity and social-ecological system.

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Mediterranean land systems are amongst the most susceptible to global change, in part due to the region’s vulnerability to climate change and misfit within a high production demanding political and societal setting. The impact of global drivers at a local scale (i.e., the possible trajectories of change of a territory) are context-dependent, and to some extent dependent on how local actors perceive them and act upon them. In this study, we focused on southeast Portugal and conducted 22 interviews and 1 collective workshop to understand how different actors across the territory anticipate the development of the region and its land systems. From our results, we get a picture of a depopulated territory, constrained by ill-adjusted policies to its harsh conditions, including little water availability and continuous depopulation. We found contrasting preferred trajectories of development for the territory. On one hand, there is a preference for prioritizing traditional land systems, usually rainfed and multifunctional. Contrasting, a need for water reservoirs that would increase water availability and allow for profitable agricultural activities and thus fixate population is recognized. The different perspectives fit with a wider debate on the role of agriculture, intensification and ecosystem services under an increasingly arid Mediterranean. The next challenge is to integrate technical expertise and knowledge with local needs and initiatives, to fit in a broader scale strategic plan. We identify a lack of technical support regarding soil health. Poor soil, from the perspective of several stakeholders, is a characteristic of the region. Knowledge dissemination is urgent so that farmers can proactively improve soil health and benefit from its capacity to increase production and retain water. We urge a higher effort from the scientific community focusing on marginal areas, supporting knowledge dissemination and analysis of the impacts of different trajectories of development.

In theory, if a new idea offers a good solution for a current problem and is properly widespread, then there is an ongoing brokering process, and, at a certain moment in time, an innovation is no longer considered as such. In the present study, we examine the case of the Montado, an agro-silvo-pastoral system in southern Portugal, to reflect on when and how innovations become custom. Integrating data from 2013 and 2017, we identified innovative initiatives that, if expanded, could reverse the current decline of the Montado system. We categorized the identified innovations as 1) social and institutional, 2) regulations and policies, 3) products and markets, and 4) farming techniques and management practices. Innovation is deemed necessary for the preservation of the Montado, yet initiatives that have existed for over 20 years are still considered innovative and an exception to the rule. At least since 2013, innovationbrokering processes have been attempted, leading us to question why these innovations are not becoming custom. By examining categories of innovations, we suggest that for innovations to become custom, changes in social and institutional arrangements need to be reinforced by regulations and policies that support changes in products and markets as well as by the adoption of new farming techniques and management practices. We conclude by suggesting a research agenda that starts aligning the evolution of the Montado system with the desired future as soon as possible.

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