Postglacial history of alpine vegetation,fire, and climate from Laguna de Río Seco,Sierra Nevada,southern Spain |
| |
| Authors: | RS Anderson G Jiménez-Moreno JS Carrión C Pérez-Martínez |
| |
| Institution: | 1. Department of Natural Systems and Resources, School of Forestry, Technical University of Madrid (UPM), Ciudad Universitaria s/n, 28040, Madrid, Spain;2. Institute of Plant Sciences, Oeschger Centre for Climate Change Research, University of Bern, Altenbergrain 21, 3013, Bern, Switzerland;3. UMR-CNRS 5805 EPOC University of Bordeaux, EPHE PSL Research University, Laboratory of Palaeoclimatology and Marine Palaeoenvironments, Allée Geoffroy Saint-Hilaire, Bât. 18, 33615, Pessac Cedex, France;4. Limnology Unit, Department of Biology, Ghent University, K.L. Ledeganckstraat 35, 9000, Ghent, Belgium;5. Department of Plant Biology, University of Murcia, 30100, Murcia, Spain;1. G.I. Arqueobiología, Instituto de Historia (CCHS), C.S.I.C., Albasanz 26-28, 28037 Madrid, Spain;2. Departamento de Botánica, Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain;1. Departamento de Estratigrafía y Paleontología, Universidad de Granada, Granada, Spain;2. Instituto Andaluz de Ciencias de la Tierra CSCI-UGR, Armilla, Granada, Spain;3. School of Earth Sciences and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ, USA;1. Departamento de Sistemas y Recursos Naturales, ETSI de Montes, Forestal y del Medio Natural, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain;2. Institute of Plant Sciences and Oeschger Centre for Climate Change Research, University of Bern, Altenbergrain 21, 3013 Bern, Switzerland;3. UMR CNRS 5805 EPOC Université de Bordeaux and EPHE Department of Palaeoclimatology and Marine Palaeoenvironments PSL Research University, Allée Geoffroy Saint-Hilaire Bât. 18N, 33615 Pessac cedex, France;4. Centre for Quaternary Research, Royal Holloway University London, Egham, TW20 0EX Surrey, United Kingdom;5. Limnology Unit, Department of Biology, Ghent University, K.I. Ledeganckstraat 35, 9000 Ghent, Belgium;6. Departamento de Biología Vegetal, Universidad de Murcia, 30100 Murcia, Spain;1. Instituto Andaluz de Ciencias de la Tierra (IACT-CSIC-UGR), Consejo Superior de Investigaciones Científicas-Universidad de Granada, Avenida de las Palmeras no 4, 18100 Granada, Spain;2. Departamento de Estratigrafía y Paleontología, Universidad de Granada, 18071, Spain;3. Departamento de Prehistoria y Arqueología. Universidad de Sevilla, Sevilla, Spain;4. Departamento de Prehistoria y Arqueología, Universidad de Granada. Granada, Spain;5. Delegación Provincial de Cultura. Junta de Andalucía, Málaga, Spain;6. Estudios geológicos y Medioambientales S.L. Las Gabias, Granada, Spain;7. School of Earth Sciences and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ, USA |
| |
| Abstract: | The Sierra Nevada of southern Spain is a landscape with a rich biological and cultural heritage. The range was extensively glaciated during the late Pleistocene. However, the postglacial paleoecologic history of the highest range in southern Europe is nearly completely unknown. Here we use sediments from a small lake above present treeline – Laguna de Río Seco at 3020 m elevation – in a paleoecological study documenting over 11,500 calendar years of vegetation, fire and climate change, addressing ecological and paleoclimatic issues unique to this area through comparison with regional paleoecological sequences. The early record is dominated by Pinus pollen, with Betula, deciduous Quercus, and grasses, with an understory of shrubs. It is unlikely that pine trees grew around the lake, and fire was relatively unimportant at this site during this period. Aquatic microfossils indicate that the wettest conditions and highest lake levels at Laguna de Río Seco occurred before 7800 cal yr BP. This is in contrast to lower elevation sites, where wettest conditions occurred after ca 7800. Greater differences in early Holocene seasonal insolation may have translated to greater snowpack and subsequently higher lake levels at higher elevations, but not necessarily at lower elevations, where higher evaporation rates prevailed. With declining seasonality after ca 8000 cal yr BP, but continuing summer precipitation, lake levels at the highest elevation site remained high, but lake levels at lower elevation sites increased as evaporation rates declined. Drier conditions commenced regionally after ca 5700 cal yr BP, shown at Laguna de Río Seco by declines in wetland pollen, and increases in high elevation steppe shrubs common today (Juniperus, Artemisia, and others). The disappearance or decline of mesophytes, such as Betula from ca 4000 cal yr BP is part of a regional depletion in Mediterranean Spain and elsewhere in Europe from the mid to late Holocene. On the other hand, Castanea sativa increased in Laguna de Río Seco record after ca 4000 cal yr BP, and especially in post-Roman times, probably due to arboriculture. Though not as important at high than at low elevations, fire occurrence was elevated, particularly after ca 3700 years ago, in response to regional human population expansion. The local and regional impact of humans increased substantially after ca 2700 years ago, with the loss of Pinus forest within the mountain range, increases in evidence of pasturing herbivores around the lake, and Olea cultivation at lower elevations. Though human impact was not as extensive at high elevation as at lower elevation sites in southern Iberia, this record confirms that even remote sites were not free of direct human influence during the Holocene. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
