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Although forest areas have been growing in Europe, some forest types have been declining regionally. Since the 1980 s, there have been reports of defoliation and mortality in evergreen oak woodlands of the Iberian Peninsula. However, long-term and large-scale trends of Iberian oak decline are still poorly understood. We quantified trends in canopy cover for cork oak (Quercus suber) and holm oak (Q. rotundifolia) woodlands in mainland Portugal for a 50 year period (1965 to 2015). We considered loss of canopy cover a proxy of forest degradation and asked how it changed over time, in association with human activity and climate. Between 1965 and 2015, both cork oak and holm oak canopy cover showed declining trends (57.9% and 71.1% of sampling points, respectively). Canopy cover dynamics, however, differed across time. Between 1965 and 1990, canopy cover gains (over 35% of sampling points) prevailed over losses (under 20%), with larger differences for cork oak than holm oak. Between 1990 and 2015, canopy cover losses (over 70% of sampling points) were much higher than gains (under 9%). Oak canopy cover decrease was associated with flatter areas (usually having more intensive land use) for both oak species, higher cattle numbers (holm oak only) and higher mean temperature (cork oak only). Contrastingly, loss of holm oak canopy cover seems to have occurred in less hot and dry regions that enable more intensive land uses. Active restoration is urgently needed to reverse the current decline in canopy cover in Mediterranean evergreen oak woodlands. [ABSTRACT FROM AUTHOR]

Human activities have drastically reshaped global forest ecosystems in recent decades. However, identifying the origins, magnitude, and primary effects of these actions, especially in East Asia (EA), with a long history of human activity, remains challenging. Crucially, unraveling the early anthropogenic impacts on forest ecosystems has substantial implications for characterizing the Anthropocene. In this study, we collated and synthesized Holocene arboreal pollen (AP) sequences from 61 EA lake basins, which demonstrated an overall expansion of forest vegetation during the early to middle Holocene, followed by a retreat from 5 cal. ka BP. The cooling and drying climate during the mid- and late Holocene proved inimical to forest proliferation across EA. Survival imperatives are likely to drive humans to adopt grazing and farming, causing a transformation from forest land to agro-pastoral land. This change further accelerated forest ecosystem degradation. By dividing EA into five subregions, we observed asynchronous declines in forest vegetation from 8 cal. ka BP to 3 cal. ka BP. This trend is primarily attributed to human impacts, given the pronounced coincidence between forest reduction and emergence and prosperity of Neolithic agriculture in each region. Significantly, the positive feedback loop between population growth and agricultural expansion can amplify human impacts. Coupled with climatic effects, these factors resulted in EA's forest vegetation plummeting to its lowest level since 10 cal. ka BP at 2.1 cal. ka BP. Furthermore, the anthropogenic influences on EA forest vegetation mirror land use, soil erosion, and vegetation variability observed globally in terms of timeline. These alterations are driven by human activities, almost coinciding with shifts in atmospheric greenhouse gas levels away from their natural trajectory. We, therefore, argue that the Anthropocene definition should consider the aggregate environmental impact of human activities over millennia, rather than restricting to the most recent centuries. [ABSTRACT FROM AUTHOR]