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Agroecosystems are vital for supplying ecosystem services to human society, but most modern farming practices impact detrimentally on the environment. Public agricultural support policies have been critically important in influencing the transformation of the farm sectors; however, few of them have been dedicated to enhancing ecosystem services beyond agricultural commodities. The largest agricultural support system worldwide, the European Common Agricultural Policy (CAP), has now come to a critical point, as major decisions concerning its design and implementation after 2013 are about to be taken. The debate on this reform process presents a unique opportunity to trigger a transition from commodity-based subsidy policies to policies centered on efficient provision of ecosystem services from agricultural land. To prompt such discussion, we formulate key recommendations informed by a review of ecosystem services literature and address verifiable links to human well-being, non-market valuation for balanced services provision, treatment of ecosystem services bundles, site-specific and regionalized approaches, matching spatial scales for different ecosystem services, funding permanence for payment schemes, strong monitoring and adaptive approaches to tackling uncertainties, and coherent cross-sectoral policy design. If these issues were to be considered in formulating and implementing future CAP, it might become an exemplar for redirecting agricultural policies elsewhere in the world towards sustainability.
Eastern Mediterranean silvopastoral oak woodlands have been greatly damaged through forest conversion, illegal lumbering, overgrazing, and forest fires. The aim of this study was to assess land-use changes and the legacies that they have imprinted on the forest structure of Quercus macrolepis and accompanying Quercus pubescens and Quercus cerris woodlands on Lesvos Island, Greece. The size-structures of adult oak populations were analyzed as indicators of long-term oak regeneration, while short-term recruitment was determined by counting oak seedlings and saplings. The size-structure of the adult Q. macrolepis population was similar to the inverse J-shaped distribution typical for natural Mediterranean oak forests, indicating continuous recruitment with a constant mortality rate of mature individuals. Seedling and sapling densities were highly variable, but generally low in relation to adult oak densities. Recruitment of oak seedlings and saplings was positively related to determinants such as forest cover, adult oak density and basal area, woody plant richness, and litter cover. Both seedling and sapling occurrence was negatively associated with dung frequency, which suggests that sheep grazing imposes a barrier to oak recruitment. The study outlines a comprehensive land-use transition from the 1950s to the 1970s, during which a complex and multifunctional agrosilvopastoral land-use system was simplified to an intensive grazing system. The discrepancy between the successful long-term regeneration and the less successful short-term recruitment of oaks illustrates that intensified livestock grazing has been a major driver of vegetation change. Grazing impact is likely to interact with increasing drought conditions, which may trigger a negative feedback cycle that undermines the capacity of woodlands to sustain ecosystem services.
Most industrial countries have experienced a transformation of land use: from decreasing to expanding forest areas, the so-called forest transition. Outside closed forests, European rural landscapes exhibit a diversity of tree-based agricultural systems, but the question of whether this forest transition has also affected ‘trees outside forests’ has rarely been studied. The aim of this study is to analyze the spatial-temporal dynamics of farm trees and woodlands in an agricultural landscape in Eastern Germany from 1964 to 2008, based on aerial photographs and digital orthophotos. Taking a landscape ecological perspective, we quantify farm tree dynamics, disentangle processes of gain and loss in the socialist and post-socialist periods of Eastern Germany, and assess differences in ecosystem services provided by farm trees. A substantial increase of overall tree cover by 24.8% was observed for the selected time period, but trajectories have been disparate across different farm tree classes. The increase in tree cover was stronger in steep valleys than on hills and plateaus, indicating a significant interdependence between topography and trajectories of change. Patch numbers of farm trees did not increase, which suggests that the expansion of tree cover is mostly due to a spatial expansion of previously existing tree patches. Overall net gains in tree cover were rather similar during the socialist and post-socialist eras. The general increase in tree cover was accompanied by increases in agriculture-related ecosystem service provision, but the increase in pollination and pest control services was much lower than that in water purification services. These findings present the first empirical evidence from an industrialized country that there is also an ongoing ‘forest transition’ outside closed forests. Potential, partially counteracting drivers of change during the socialist and post-socialist periods have mainly been related to farm policies and the environmental consciousness of land users and society as a whole.
The potential of agriculture, forestry, and other land uses to sequester carbon offers a powerful tool for controlling the global climate regime, but practices capable of creating “collateral” benefits for landscape conservation have thus far been disregarded. This paper calls for greater integration of scattered trees into agricultural landscapes, hypothesizing that agroforestry practices effectively store carbon and deliver other important ecosystem services as well. Several agroforests from the Upper Lusatia area in Eastern Germany have been selected for analysis. They cover relatively large areas of land (8.2%), even within this intensively used agricultural landscape, and their extent increased from 1964-2008 by 19.4%. Practices of conserving or promoting the six agroforest classes are compared with a catalogue of essential properties for becoming effective “carbon offset projects”. Criteria from mandatory and voluntary carbon markets for carbon sequestration are then applied (additionality, baselines, permanence, and carbon leakage). The study concludes that steps towards realization of “carbon sequestration projects” should include collecting empirical evidence regarding the carbon sequestration potential of temperate agroforestry systems, developing localised demonstration projects, and upscaling these projects to participate in established carbon markets.