GEOSCAN, résultats de la recherche


TitreResilience of peatland ecosystem services over millennial timescales: evidence from a degraded British bog
AuteurSwindles, G T; Morris, P J; Wheeler, J; Smith, M; Bacon, K L; Turner, T E; Headley, A; Galloway, J M
SourceEcology vol. 104, 2016 p. 621-636, (Accès ouvert)
Séries alt.Secteur des sciences de la Terre, Contribution externe 20150271
ÉditeurBritish Ecological Society
Documentpublication en série
Mediaen ligne; numérique
Lat/Long OENS -39.1667 -38.5000 47.6333 47.5667
Sujetstourbe; tourbières; analyses de la tourbe; écosystèmes; peuplements biologiques; biogéologie; géologie de l'environnement
Illustrationstables; images; graphs
ProgrammeOutils d'adaptation et d'impacts sur l'environnement pour les mines de métaux, Géosciences environnementales
Diffusé2016 03 17
Résumé(disponible en anglais seulement)
Many peatland ecosystems in Europe have become degraded in the last century owing to the effects of drainage, burning, pollution, and climate change. There is a need to understand the drivers of peatland degradation because management and restoration interventions have implications for the natural ecohydrological dynamics of such sensitive environments, and also attract substantial costs. However, if given enough time peatlands may have the ability to recover spontaneously without deliberate action.We use a comprehensive multiproxy palaeoecological dataset from a degraded raised bog in Northern England to examine its ecosystem stability and long-term dynamics in response to anthropogenic disturbance over a variety of timescales. One feature of many degraded peatlands (including our study site)is the local dominance of Molinia caerulea (Purple Moor-grass), which has expanded at the expense of characteristic peatland plants, including sedges and Sphagnum mosses. Our data show that there has been a long history of human impacts at the site which have led to its current unfavourable condition. Several distinct episodes of peat cutting are evident as hiatuses in peat accumulation; however, peat accumulation and plant community structure has subsequently recovered each time. The appearance of M. caerulea occurs coevally with an unprecedented variety of recent anthropogenic impacts, all of which have contributed to providing a suitable environment for its rise to dominance. We have dated this to the latter half of the twentieth century which corresponds to a number of anthropogenic press disturbances, including: dust loading from post-war expansion of the adjacent quarry; burning; drainage; airborne pollution; and contamination from soil dust and agrochemicals.Our work demonstrates the importance of palaeoecology for understanding the trajectories of peatland ecosystem dynamics, including their resilience and resistance to pulse and press disturbances. We show that peatlands have the capability to recover spontaneously from severe disturbances such as peat cutting, albeit on timescales much longer than those applied to monitoring of restoration efforts. The implications are relevant to determining whether it is better to manage and restore peatlands, or to allow them without human intervention.
Résumé(Résumé en langage clair et simple, non publié)
Notre travail se penche sur les trajectoires des dynamiques des écosystèmes de tourbes, incluant leurs résiliences et résistance aux rythmes et pressions des perturbations. Nous savons que les tourbières ont la capacité de se régénérer spontanément après de sévères perturbations comme des coupes, bien que ce soit sur des échelles de temps beaucoup plus grandes que celles utilisées pour faire le suivi d'efforts de restauration. Les implications sont pertinentes pour déterminer s'il faut gérer et restaurer les tourbières ou les laisser se régénérer naturellement.