The Role of Canopy Cover Dynamics over a Decade of Changes in the Understory of an Atlantic Beech-Oak Forest

Forests

Mercedes Valerio¹  Ricardo Ibáñez¹  Antonio Gazol² 

[1] Departamento de Biología Ambiental, Facultad de Ciencias, Universidad de Navarra, Calle Irunlarrea 1, 31008 Pamplona, Spain;Instituto Pirenaico de Ecología (CSIC), Avenida Montañana 1005, 50059 Zaragoza, Spain;

关键词: community ecology;    understory species;    canopy gap;    niche;    temporal variation;    seed bank;   

DOI  :  10.3390/f12070938

来源: DOAJ

【 摘 要 】

The understory of temperate forests harbour most of the plant species diversity present in these ecosystems. The maintenance of this diversity is strongly dependent on canopy gap formation, a disturbance naturally happening in non-managed forests, which promotes spatiotemporal heterogeneity in understory conditions. This, in turn, favours regeneration dynamics, functioning and structural complexity by allowing changes in light, moisture and nutrient availability. Our aim is to study how gap dynamics influence the stability of understory plant communities over a decade, particularly in their structure and function. The study was carried out in 102 permanent plots (sampled in 2006 and revisited in 2016) distributed throughout a 132 ha basin located in a non-managed temperate beech-oak forest (Bertiz Natural Park, Spain). We related changes in the taxonomical and functional composition and diversity of the understory vegetation to changes in canopy coverage. We found that gap dynamics influenced the species composition and richness of the understory through changes in light availability and leaf litter cover. Species with different strategies related to shade tolerance and dispersion established in the understory following the temporal evolution of gaps. However, changes in understory species composition in response to canopy dynamics occur at a slow speed in old-growth temperate forests, needing more than a decade to really be significant. The presence of gaps persisting more than ten years is essential for maintaining the heterogeneity and stability of understory vegetation in old-growth temperate forests.

【 授权许可】

Unknown