Top-down segregated policies undermine the maintenance of traditional wooded landscapes: Evidence from oaks at the European Union’s eastern border

Abstract

Semi-open oak woods and solitary oaks commonly dominate the wooded fabric (i.e. the 'oakscape') of European traditional rural agricultural landscapes based on animal husbandry. However, modern land use systems fail to perpetuate oakscapes, posing a serious threat to biodiversity conservation and the associated diversity of ecosystem services. Reconstructing the dynamics of oakscape remnants can provide valuable insights concerning the maintenance of oakscapes. We used the socioeconomic transitions at the European Union's eastern border as a natural experiment to explore the drivers for successful oak recruitment in 27 selected units representing 4 oakscape categories. Analyses of tree-ring data, historical maps, and orthophotos were used to reconstruct the oakscapes' establishment trajectories in relation to land use changes in the period 1790-2010. The oaks in cultural semi-open woods and wood-pastures differed substantially from those in closed canopy forests by more stocky shape and faster early age DBH annual increase. We found two distinct recruitment patterns: (1) FASTrecruitment usually completed within 2-3 decades, attributed to an unconstrained succession of abandoned agricultural land, and (2) SLOWrecruitment extending over several or more decades. In Ukraine, frequent illegal grass burning in marginal woods was the most successful mechanism perpetuating oak recruitment. Top-down policy encouraging specialized intensive farming, sustained yield forestry, and conservation efforts concentrated on the preservation of closed canopy forests compromise the future of traditional agro-silvo-pastoral systems. Maintenance of traditional integrated agro-silvo-pastoral management sustaining oakscapes needs to combine local traditional knowledge and landscape stewardship.

Influence of canopy openness, ungulate exclosure, and low‐intensity fire for improved oak regeneration in temperate Europe

“…Rather multiple fires have been more successful (Dey & Hartman, ; Hutchinson et al, ). This corresponds to Ziobro et al () and Bobiec et al (), who reported that reoccurring grass burning promoted Q. robur regeneration by reducing competing shade‐tolerant species in Ukrainian woodlands. We, therefore, suggest that additional experiments involving multiple burning events are needed to determine whether reoccurring fire provides Q. robur and Q. petraea competitive advantage.…”

“…Rather multiple fires have been more successful (Dey & Hartman, 2005;Hutchinson et al, 2012). This corresponds to Ziobro et al (2016) and Bobiec et al (2019) (Brose et al, 2014). Though burning was conducted at the very end of the growing season in this study, it is likely that the timing of the burns we applied impacted plants that were physiologically active.…”

“…The reduction of conifer reproduction that we observed through burning supports the application of low‐intensity fire as an efficient management tool in such situations. Fire would likely also be efficient in situations where shade‐tolerant F. sylvatica and C. betulus constitute the main competitors, which is often the case in central temperate Europe (Bobiec et al, ; Ziobro et al, ). However, further research is needed in several areas before we can recommend prescribed burns in oak‐dominated forests.…”

“…In addition to sufficient light, successful oak regeneration hinges on a variety of other factors that often influence each other, including competing vegetation, ungulate browsing, and site conditions (Annighöfer et al, 2015;Harmer, 2001;Jensen & Löf, 2017;Lorimer, Chapman, & Lambert, 1994). Though knowledge is lacking regarding the combined influence of different disturbance types on suitable environmental conditions, traditional land-use systems that included grazing regimes, utilization of low-intensity fire, and cutting of shade-tolerant trees, likely promoted oak regeneration (Bobiec et al, 2019;Bobiec, Reif, & Öllerer, 2018;Vera, 2000).…”

“…However, reconstructions of past forest conditions suggest that fire may have had an important role in the dynamics of certain temperate European forest types as well (Bradshaw & Lindbladh, 2005;Niklasson, Lindbladh, & Björkman, 2002;Niklasson et al, 2010;Tinner, Conedera, Ammann, & Lotter, 2005). In western Ukraine, woodland fires may effectively prevent understory development of hazel (Corylus avellana L.), hornbeam (Carpinus betulus L.), and beech (Fagus sylvatica L.), thereby favoring pedunculate oak (Quercus robur L.) reproduction (Bobiec et al, 2019;Ziobro et al, 2016). Moreover, Adámek, Hadincová, and Wild (2016) found that survival rates of sessile oak [Quercus petraea (Matt.)…”