Search results for "Cultura."
showing 10 items of 14458 documents
The Bronze Age in France
2013
A Serravallian (Middle Miocene) shark fauna from Southeastern Spain and its palaeoenvironment significance
2017
The study of a new Serravallian (Middle Miocene) locality from the Southeastern Spain has yielded a shark assemblage characterized by microremains of at least seven taxa (Deania calcea, ¿Isistius triangulus, ¿Squaliolus cf. S. schaubi, ¿Paraetmopterus sp., Pristiophorus sp., Scyliorhinus sp. and a cf. Squaliformes indet) of three different orders (Squaliformes, Pristiophoriformes and Carcharhiniformes). In addition, associated macroremains have also been found, including teeth of ¿Cosmopolitodus hastalis, Isurus sp., Hemipristis serra, Odontaspis sp., Carcharhinus spp. and ¿Otodus (Megaselachus) megalodon. The assemblage contains taxa with disparate environmental preferences including not o…
Muridae from the late Miocene site of Venta del Moro (Eastern Spain)
2016
AbstractMurids are usually the dominant faunas of the late Miocene and early Pliocene micromammal assemblages. The present work deals with the murid faunas of the well-known late Miocene locality of Venta del Moro, comprising over 2700 molars ascribed to the taxa Apodemus gorafensis, Occitanomys alcalai, Paraethomys meini and Stephanomys dubari. This list differs from those of previous studies by the presence of A. gorafensis instead of A. gudrunae. The presence of A. gudrunae in younger localities than Venta del Moro implies that both species, considered ancestor and descendant, coexisted for some time. In addition, the analysis of such an extensive collection has allowed us to check the v…
New advances on the Aurignacian in the central Iberian Mediterranean basin
2021
Abstract This study aims to obtain a chronological and cultural framework of the Evolved Aurignacian in the central Iberian Mediterranean basin and find agreement between this framework and other sequences of the Iberian southeast. Over the last few years, there has been remarkable progress in the research of the Evolved Aurignacian sites in the Valencian area, making a review of the main characteristics of the technocomplex on a regional scale necessary. The recent fieldwork carried out in Cova de les Malladetes (Valencia) and in Cova de les Cendres (Alicante) have been key to understanding the lithic, osseous and ornament assemblages ascribed to the Evolved Aurignacian. Several Bayesian m…
Soil physicochemical and microbial drivers of temperature sensitivity of soil organic matter decomposition under boreal forests
2020
Abstract Soil organic matter (SOM) in boreal forests is an important carbon sink. The aim of this study was to assess and to detect factors controlling the temperature sensitivity of SOM decomposition. Soils were collected from Scots pine, Norway spruce, silver birch, and mixed forests (O horizon) in northern Finland, and their basal respiration rates at five different temperatures (from 4 to 28 °C) were measured. The Q10 values, showing the respiration rate changes with a 10 °C increase, were calculated using a Gaussian function and were based on temperature-dependent changes. Several soil physicochemical parameters were measured, and the functional diversity of the soil microbial communit…
The revolution of crossdating in marine palaeoecology and palaeoclimatology.
2019
Over the past century, the dendrochronology technique of crossdating has been widely used to generate a global network of tree-ring chronologies that serves as a leading indicator of environmental variability and change. Only recently, however, has this same approach been applied to growth increments in calcified structures of bivalves, fish and corals in the world's oceans. As in trees, these crossdated marine chronologies are well replicated, annually resolved and absolutely dated, providing uninterrupted multi-decadal to millennial histories of ocean palaeoclimatic and palaeoecological processes. Moreover, they span an extensive geographical range, multiple trophic levels, habitats and f…
How ocean acidification can benefit calcifiers.
2017
Reduction in seawater pH due to rising levels of anthropogenic carbon dioxide (CO2) in the world's oceans is a major force set to shape the future of marine ecosystems and the ecological services they provide [1,2]. In particular, ocean acidification is predicted to have a detrimental effect on the physiology of calcifying organisms [3]. Yet, the indirect effects of ocean acidification on calcifying organisms, which may counter or exacerbate direct effects, is uncertain. Using volcanic CO2 vents, we tested the indirect effects of ocean acidification on a calcifying herbivore (gastropod) within the natural complexity of an ecological system. Contrary to predictions, the abundance of this cal…
Conflicting objectives in production forests pose a challenge for forest management
2017
Conflicts among different ecosystem services have been shown to be common and potentially exacerbated by management interventions. In order to improve the sustainability of natural resource use, the occurrence of these conflicts and the effects that management actions have on them need to be understood. We studied the conflicts between ecosystem services and the potential to solve them by management choices in boreal production forests. Our study area consisted of nearly 30,000 forest stands which were simulated for 50 years into the future under alternative management scenarios. The study included four ecosystem services – timber production, bilberry production, carbon storage, and pest re…
Stochastic models for phytoplankton dynamics in Mediterranean Sea
2016
Abstract In this paper, we review some results obtained from three one-dimensional stochastic models, which were used to analyze picophytoplankton dynamics in two sites of the Mediterranean Sea. Firstly, we present a stochastic advection–reaction–diffusion model to describe the vertical spatial distribution of picoeukaryotes in a site of the Sicily Channel. The second model, which is an extended version of the first one, is used to obtain the vertical stationary profiles of two groups of picophytoplankton, i.e. Pelagophytes and Prochlorococcus, in the same marine site as in the previous case. Here, we include intraspecific competition of picophytoplanktonic groups for limiting factors, i.e.…
Trophic state changes can affect the importance of methane-derived carbon in aquatic food webs
2017
Methane-derived carbon, incorporated by methane-oxidizing bacteria, has been identified as a significant source of carbon in food webs of many lakes. By measuring the stable carbon isotopic composition (δ13C values) of particulate organic matter, Chironomidae andDaphniaspp. and their resting eggs (ephippia), we show that methane-derived carbon presently plays a relevant role in the food web of hypertrophic Lake De Waay, The Netherlands. Sediment geochemistry, diatom analyses and δ13C measurements of chironomid andDaphniaremains in the lake sediments indicate that oligotrophication and re-eutrophication of the lake during the twentieth century had a strong impact on in-lake oxygen availabili…