RESUMO
BACKGROUND: The Biological Field Station of Paimpont (Station Biologique de Paimpont, SBP), owned by the University of Rennes and located in the Brocéliande Forest of Brittany (France), has been hosting student scientific research and field trips during the last 60 years. The study area of the SBP is a landscape mosaic of 17 ha composed of gorse moors, forests, prairies, ponds and creeks. Land use has evolved over time. Historical surveys by students and researchers focused on insects and birds. With this study, we aimed to increase the range of taxa observations, document changes in species composition and landscape and provide a basis for interdisciplinary research perspectives. We gathered historical data, implemented an all-taxon biodiversity inventory (ATBI) in different habitats of the SBP study area, measured abiotic factors in the air, water and soil and performed a photographical landscape observation during the BioBlitz held in July 2017. NEW INFORMATION: During the 24 h BioBlitz, organised by the SBP and the EcoBio lab from the University of Rennes and the French National Center of Scientific Research (CNRS), different habitats were individually sampled. Seventy-seven experts, accompanied by 120 citizens and 12 young people participating in the European Volunteer Service, observed, identified and databased 660 species covering 5 kingdoms, 8 phyla, 21 classes, 90 orders and 247 families. In total, there were 1819 occurrences including records identified to higher taxon ranks, thereby adding one more kingdom and four more phyla. Historical data collection resulted in 1176 species and 4270 occurrences databased. We also recorded 13 climatic parameters, 10 soil parameters and 18 water parameters during the BioBlitz. Current habitats were mapped and socio-ecological landscape changes were assessed with a diachronic approach using 32 historical photographs and historical maps. The coupling of historical biodiversity data with new biotic and abiotic data and a photographic comparison of landscape changes allows an integrative understanding of how the SBP changed from agriculturally-used land to a managed natural area within the last 60 years. Hence, this BioBlitz represents an important holistic sampling of biodiversity for studies on trophic webs or on trophic interactions or on very diverse, but connected, habitats. The integration of social, biotic and abiotic data opens innovative research opportunities on the evolution of socio-ecosystems and landscapes.
RESUMO
Various studies using pollen stratigraphies have demonstrated significant correlations between Holocene plant diversity, climate, and human activities. Studies that have analyzed longer Holocene timescales tend to discuss cultural data very superficially. This is remarkable because detailed insights into past human activities may be key to gain an understanding of the observed trends in biodiversity. This study aims to reconstruct and explain spatio-temporal trends in past plant diversity (alpha, temporal, and spatial beta diversity) by integrating data on vegetation dynamics, human subsistence economy, and land-use patterns. The landscape of Northwest France during the greater part of the Iron Age and the start of the Roman period (600 BC-AD 100) is selected as a case study. In total, 30 high-quality pollen-stratigraphical sequences allow for the reconstruction of the main long-term trends in plant diversity and more generally of the changing fabric of the landscape. Additionally, increasingly detailed images of the Iron Age rural landscape are available because of a steep increase in archaeological data (aerial photography, surveys, and excavations). These different types of data are integrated and used as input for a wider discussion on the relation between human activities and plant diversity. In general, the taxonomic richness increases steadily during the period under study. Some spatio-temporal differences are observed. The increasing richness values correspond with the growing impact of human activities on the landscape. Archaeologically documented land-use changes on smaller timescales are less clearly reflected in the richness values and vegetation dynamics, which might result from the (large-scale) research design.