Vegetation history and climate of the last 15,000 years at Laghi di Monticchio, southern Italy
ABSTRACT In southern Italy, vegetation contemporary with the end of the last glacial maximum, from 15,000 to 12,000 years ago, is shown by pollen-analysis to have been treeless and steppe-like in character. At 12,500 BP (years before present), Betula (birch) expanded into the steppe, quickly followed by Quercus (oak), Fagus (beech), Tilia (lime) and other tree genera of mesic forest. High percentages of Tilia point to a rich mesic forest that was contemporary with the ‘Allerød’ interstadial of northern Europe. A major decline in mesic trees with an accompanying return of Betula and steppe genera dated to 10,500 years ago identifies a ‘Younger Dryas’ climatic reversal. Betula and steppe genera were replaced by forest of Quercus and other mesic trees, notably Ulmus (elm), as the Holocene began. In the later Holocene, ca. 4000 years ago, Abies (fir), Carpinus betulus (hornbeam) and Taxus (yew) appeared. Abies and Taxus became extinct locally about 2500 years ago, either because of climatic change, or perhaps because of the effects of early agriculture. The Full-glacial climate is thought to have been cold and summer-dry with mainly winter precipitation. The Lateglacial ‘Bølling-Allerød’ Interstadial was summer-wet and warm. The response-surface based climate reconstruction indicates an early Holocene climate with markedly colder winter conditions than today, about −5°C compared with 3.9°C today as a mean temperature for the coldest month. The annual temperature sum is reconstructed as somewhat higher than today, 3500 degree days as compared with a calculated value of 2900 for today. The later Holocene had a climate like today's. Rainfall, and variation in its seasonal distribution, has been a critical determinant of the vegetation cover. The fossil pollen record at Laghi Di Monticchio has been complemented by diatom and plant macrofossil studies which provide evidence of former lake environments as well as data on the upland forest. Lake levels remained high during the Full- and Lateglacial with encroachment of shore vegetation during the Holocene. The sediments also have an exceptionally rich record of tephra falls which are of importance in dating and core correlation. Twenty-one macroscopically visible tephras occur in sediments of the last 15,000 years.
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- "A huge amount of yew was exported from Austria to England for preparing crossbows in the middle age to late 18 th century and heavily removed in the last century by human due to the risk of domestic animals especially horses being poisoned by eating parts of the yew   . In southern Italy it became locally extinct about 2500 years ago . There are many archaeological records of the use of yew from Neolithic to Roman as, for example, spears, axe shafts, or bows  . "
ABSTRACT: Human interventions and land-use changes effected the structure and species composition of the temperate forests in Europe. The English yew (Taxus baccata L.) populations have been negatively affected by this ongoing process which led to a decrease of most of their ranges all over Europe. Yew is distinct from the other evergreen coniferous tree species: it is a dioecious, long living, non-resinous gymnosperm. Although yew is getting priority for conservation activities the knowledge about conservation management is scarce. Several studies on the ecology, genetics and management of yew populations in Austria try to overcome this knowledge gap. The most significant risk factors for the viability of yew populations are light availability, browsing, tree competition, illegal logging, and lack of public awareness. Findings have shown that a shortcoming of certain regeneration height classes is evident, although most of the population indicated abundant number of one-year seedlings. Considering the vitality of the adult yews it reveals that vitality is related to tree height and DBH as well as influenced by the inter-specific competition of the neighbouring tree species. For the analysis of the genetic structure, English yew populations showed a high level of genetic variation (He = 0.274 and Ho=0.238) with a medium level of inbreeding (0.130). The conservation propositions of English yew in the Eastern Alps are discussed in the light of ecological condition, genetic structure and social aspect of this species.Endangered Species: Habitat, Protection and Ecological Significance, 1st edited by Manuel Esteban Lucas-Borja, 01/2013: chapter One: pages 1-16; NOVA Publisher., ISBN: 978-1-62257-532-9
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- "During the early Neolithic period, the mean annual temperature is supposed to have been somewhat higher than at present, and probably coincides with the Optimum Climaticum that in Sardinia has been estimated at around 8000 BP (Watts et al., 1996; Cacho et al., 2001; Rohling et al., 2002; Porcu et al., 2007). Apparently, also in Sardinia, and at Sa Punta (5476e5028 2s cal BC) specifically, the vegetational assessment is mainly induced by climate; the human impact seems not to produce remarkable effect on the environment. "
ABSTRACT: The major goal of the present study has been to assess the ecological context of the Early Neolithic settlement under excavation in the coastal site of Sa Punta-Marceddì (Terralba, Sardinia, Italy) where a trench of Neolithic age has been brought to light. Based on the origins of the site's organic fossiliferous content, the purpose of this work is to achieve an understanding of: 1) the reasons why this location was chosen by EN man and 2) its functions. This research has enabled us to suggest a human paleoecological scenario over the course of the last three centuries of the 6th millennium BC in the inland area of the Oristano Gulf. On the basis of pollen spectra and the phytolith morphologies recognised, it is suggested that herbaceous vegetation covered the alluvial plain. Arable agriculture does not seem to have been practiced on the site, but the record of coprophilous fungi and endoparasites, along with clues that there were burning practices, suggest livestock farming activity. To date, a univocal interpretation of the function of this trench is still lacking. However, it is the oldest and the only evidence in Sardinia of a remarkable transformation of an open-air space due to settlement.Journal of Archaeological Science 05/2012; 39(5):1260-1270. DOI:10.1016/j.jas.2012.01.014 · 2.20 Impact Factor
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- "Among these peat-forming communities composed by Cyperaceae, ferns, Alnus glutinosa/incana and Salix (Fig. 5), a few appear to be assignable to alder carrs (Fig. 6). Alder communities been recorded during the Holocene throughout the whole Europe, from southern Spain (Carrión et al., 2003) and southern Italy (Watts et al., 1996) to Fennoscandia (Tallantire, 1974). Their postglacial dynamics have been strongly dependent on local conditions: some alder carrs were successional stages that have been later replaced by mature forests (Tallis, 1983; Walker, 1970), but others were stable and long-persisting communities (Barthelmes et al., 2006; Marek, 1965), sometimes through cyclic successions with sedge fens (Pokorný et al., 2000). "
ABSTRACT: Wetland conservation and management are generally only based on present-day studies, without integrat-ing historical considerations. However, wetlands contain palaeoecological archives that can provide accu-rate records of their own history. Our study aims at reconciling this paradox in the central French Alps, by reconstructing the past wetland diversity/richness and the controls of Holocene hydroseral dynamics, and by discussing on this historical basis their conservation, management and restoration. Previously pub-lished data, complemented by the palaeoecological study of a sedge mire, reveal three main stages in the regional hydroseral succession: initial aquatic plant communities (Nymphaea alba, Nuphar cf. lutea, Menyanthes trifoliata), carrs (Alnus glutinosa/incana, Salix spp., Thelypteris palustris), then sedge meadows (Cyperaceae, Poaceae, Lythrum salicaria…). This dynamic comprises (1) a classical evolution from open water bodies to treed wet communities, controlled by the relationships between sedimentation processes and climate, and (2) an unexpected return to herbaceous wet habitats mainly triggered by Subatlantic human-induced managements. Such recent changes induced in the studied region the decline of Alnus cf. glutinosa, the disappearance of Thelypteris palustris, and the extinction of the carr communities they consti-tuted. The historically-based assessment of community naturalness and resilience appears critical for defin-ing conservation priorities, refining management actions, and identifying baseline conditions for restoration initiatives. The main implications of our results are to reinforce conservation measures on the less impacted habitats and to increase the diversity/richness of isolated lowland mires, notably by restoring alder communities in some of them.Review of Palaeobotany and Palynology 01/2012; 171:124-139. DOI:10.1016/j.revpalbo.2011.12.005 · 1.94 Impact Factor