Search results for "pea"
showing 10 items of 6599 documents
From USSR to EU: 20 years of rural landscape changes in Vidzeme, Latvia
2012
Landscape changes have been observed throughout rural Europe over the past decades in relation to intensifying agriculture and land marginalisation. This is particularly true for Central and Eastern Europe as drastic political and socio-economic changes have taken place over the past century, as is the case for Latvia. Using a detailed time series of high-resolution remotely sensed images spanning from 1988 to 2007, the landscape structure (composition and configuration) in Vidzeme, central Latvia, is examined and compared between periods. Major recent events for the country, such as independence and entry into the European Union are covered. The effect on landscape structure of various soc…
Age and sedimentary record of inland eolian sediments in Lithuania, NE European Sand Belt
2015
We present a study based on four inland eolian locations in Eastern, Central and Southeastern Lithuania belonging to the northeastern part of the ‘European Sand Belt’ (ESB). Although there have been several previous studies of the ESB, this north-eastern extension has not been investigated before in any detail. The sedimentary structural–textural features are investigated and a chronology was derived using optically stimulated luminescence on both quartz and feldspar. The sedimentary structures and the rounding and surface characteristics of the quartz grains argue for a predominance of eolian transport. Additionally, some structural alternations and a significant contribution of non-eolian…
The north-eastern aeolian ‘European Sand Belt’ as potential record of environmental changes: A case study from Eastern Latvia and Southern Estonia
2016
Abstract The Latvian and Estonian inland dunes belong to the north-eastern part of the ‘European Sand Belt’ (ESB). These dunes are widely distributed over broad glaciolacustrine plains and Late Glacial alluvial deltas, considered to be potential sources for the aeolian material. Little is known about these aeolian sediments and their substratum; here we present a detailed sedimentary structural and textural characterisation together with a luminescence-based chronology. Through a comparison between grain-size, rounding of quartz grains and surface characteristics in medium/coarse (0.5–0.8 mm) sand, and the light mineral content, we found an alternation of aeolian and periglacial components.…
An intractable climate archive — Sclerochronological and shell oxygen isotope analyses of the Pacific geoduck, Panopea abrupta (bivalve mollusk) from…
2008
Abstract Annual growth increment patterns of cardinal teeth (CT) of Panopea abrupta (Conrad) can reportedly provide information about past climate variations. However, little is known about the intra-annual timing and rate of shell growth necessary to interpret such records. In addition, it remains unclear whether actual temperatures can be reliably inferred from δ18O values of geoduck {goo'e-duk} shells. This study compared high-resolution environmental records (hourly to monthly resolved temperature, bi-weekly to monthly δ18Owater and salinity data) with temperatures reconstructed from oxygen isotope values of the outer shell layer (Tδ18OOSL) and cardinal tooth portions (Tδ18OCT) of diffe…
Carbon accumulation rate in a raised bog in Latvia, NE Europe, in relation to climate warming
2018
The carbon accumulation rate (CAR) over the last 180 years was estimated by measuring carbon concentrations in 1-cm layers in a fine-resolution dated and analysed peat sequence in Teiči Bog, Latvia, NE Europe. We used the Granger causality test to examine the temporal (lagged) relationships between the CAR and the historical climate variables. Our results showed that the average CAR was 192 g C m–2 yr–1 during the last 180 years and 169 g C m–2 yr–1 when excluding the acrotelm where decomposition and the stock of carbon are still not in the balance. The Granger causality test showed significant positive temporal associations between the temperature and the CAR, indicating that the temperatu…
The response of a shallow lake and its catchment to Late Glacial climate changes — A case study from eastern Poland
2015
In this study we investigate how climate fluctuation in the Late Glacial period influenced the development of a lake and its catchment located in the East European Plain. We analyzed the sediments of the lake for pollen, subfossil Cladocera, macrofossils and chemical composition. We aimed at disentangling: (1) the climate changes and their limno-ecological responses, (2) temperature dynamics with the use of Cladocera-based transfer function (MJT) and macrofossil-based reconstruction of mean minimum July temperature (MMJT), (3) timing of the response of different proxies to environmental changes. The results of multiproxy analyses explicitly suggest that the main driver for changes in aquati…
Experimental basis in lithic arrows usage and hafting at the end of the last glaciation in the French Alps
2017
Abstract To identify lithic arrowheads from Prehistoric sites is very difficult because there is a great variability in their morphology and in the ways of hafting and throwing them. Variables playing in their use are numerous. Some experimental approaches try to explain traces in prehistorical lithic points by mean of paying attention at some of these variables. Many researchers have used morphological parameters to distinguish spear from arrowheads, showing which characteristics define the potential of each type of weapon in ethnographical examples. However, only an accurate use-wear analysis that pays attention on macro and micro-wear traces and which is grounded on systematically experi…
A 2000-year record of lake ontogeny and climate variability from the north-eastern European Russian Arctic
2016
A lake sediment record from the north-eastern European Russian Arctic was examined using palaeolimnological methods, including subfossil chironomid and diatom analysis. The objective of this study is to disentangle environmental history of the lake and climate variability during the past 2000 years. The sediment profile was divided into two main sections following changes in the lithology, separating the limno-telmatic phase between ~2000 and 1200 cal. yr BP and the lacustrine phase between ~1200 cal. yr BP and the present. Owing to the large proportion of semi-terrestrial chironomids and poor modern analogues, a reliable chironomid-based temperature reconstruction for the limno-telmatic p…
Identifying fossil rabbit warrens: Insights from a taphonomical analysis of a modern warren
2016
14 pages; International audience; The European rabbit is a small burrowing mammal that is particularly abundant in Western Europe since the Pleistocene and introduced around the world over the last few centuries. Rabbit bones are regularly recovered from archaeological and palaeontological sites; however, demonstrating their contemporaneity with associated material is often difficult. Additionally, determining the origin of rabbit remains in fossil sites is equally problematic due to the lack of reference collections for natural accumulations. In order to address these issues, we excavated a modern rabbit warren in southwestern France using modern archaeological field methods and techniques…
Five centuries of Central European temperature extremes reconstructed from tree-ring density and documentary evidence
2010
Future climate change will likely influence the frequency and intensity of weather extremes. As such events are by definition rare, long records are required to understand their characteristics, drivers, and consequences on ecology and society. Herein we provide a unique perspective on regional-scale temperature extremes over the past millennium, using three tree-ring maximum latewood density (MXD) chronologies from higher elevations in the European Alps. We verify the tree-ring-based extremes using documentary evidences from Switzerland, the Czech Republic, and Central Europe that allowed the identification of 44 summer extremes over the 1550-2003 period. These events include cold temperat…