Search results for "VEGETATION"
showing 10 items of 1069 documents
The use of wood in funerary pyres: random gathering or special selection of species? Case study of three necropolises from Poland
2012
Abstract In this study, the analysis of charcoal remains from three prehistoric necropolises is presented. This botanical material formed part of funerary pyres and thus represents purposely gathered wood used for cremation ceremonies. Therefore, its anthracological analysis may indicate a special selection of wood, which may be a source of palaeoethnographic information about past rituals. However, a question remains as to whether or not the charcoal assemblages that originated from graves may also provide some palaeoecological information. In order to test both hypotheses, analysis of three Polish necropolises dating to the Bronze and the Iron Age were performed. In all charcoal assemblag…
Vegetation changes and human action from the Neolithic to the Bronze Age (7000?4000 B.P.) in Alicante, Spain, based on charcoal analysis
1994
Charcoal analysis reveals various palaeo-ecological phases from the Neolithic to the Bronze Age. Agriculture starts about 7000 B.P. in favourable ecological conditions. Most of the charcoal spectra from sites on the coast represent thermomediterranean holm-oak forest; those from the inland mountains represent mesome-diterranean holm-oak forest. The Neolithic I Impressed Ware people were the first to clear the forest to plant their crops. This clearance of primary woodland resulted in the development of secondary vegetation of pine woods or scrub. The scrub reached its maximum during the Bell Beaker phase and Bronze Age in the Cova de les Cendres. In the Neolithic II open air sites, the perc…
Mid-Holocene vegetation dynamics in the Tejo River estuary based on palaeobotanical records from Ponta da Passadeira (Barreiro-Setúbal, Portugal)
2014
This paper presents the results of pollen and charcoal analyses carried out in the sedimentary formation of Ponta da Passadeira, south of the Tejo River estuary, Portugal. The data provide information regarding the evolution of the coastline and ecosystem of the estuary during the mid and late Holocene. The study focuses on a group of upright woody fossilized tree remains that, together with those identified earlier by Garcia-Amorena et al. (2007), form part of the fossil forest of Ponta da Passadeira. Eight remains were identified as Pinus pinaster, four as Pinus pinea and one as Pinus sp. Two specimens of these species were dated to 6523 and 5805 cal. a BP. Pollen analysis was undertaken …
The effects of vegetation on indoor thermal comfort: the application of a multi-scale simulation methodology on a residential neighborhood renovation…
2017
Abstract Despite the acknowledged positive effects of vegetation at urban, neighborhood and building scales, there are still only limited comprehensive design tools for multi-scale evaluation of the microclimate and thermal benefits of plants and building-integrated vegetation (BIV) systems. The paper describes a case study in the city of Palermo (Italy) that applied simulation methodology to quantitatively assess the microclimate effects of different neighborhood and building retrofit scenarios where vegetation plays a main role. The simulation workflow moves from a micro-urban to a building scale assessment by linking the ENVI-met software to the building energy simulation program EnergyP…
Potential of Natural Ventilation and Vegetation for Achieving Low-Energy Tall Buildings in Tropical Climate: An Overview
2019
Climate change and rise in urban temperatures have further increased the cooling load demands for tall buildings located in hot climatic regions. Cooling loads in tall buildings can be reduced by integrating them with natural ventilation (NV) and building integrated vegetation (BIV) techniques. This study explores the potential of NV and BIV for obtaining low-energy buildings by analyzing ten tall buildings as case studies. Buildings are analyzed for NV, BIV, architecture design parameters, and energy savings. The results show that mixed-mode ventilation is the most commonly employed, and circular building plans have the highest potential for energy savings. Furthermore, the combination of …
Feasibility of hyperspectral vegetation indices for the detection of chlorophyll concentration in three high Arctic plants: Salix polaris, Bistorta v…
2018
Remote sensing, which is based on a reflected electromagnetic spectrum, offers a wide range of research methods. It allows for the identification of plant properties, e.g., chlorophyll, but a registered signal not only comes from green parts but also from dry shoots, soil, and other objects located next to the plants. It is, thus, important to identify the most applicable remote-acquired indices for chlorophyll detection in polar regions, which play a primary role in global monitoring systems but consist of areas with high and low accessibility. This study focuses on an analysis of in situ-acquired hyperspectral properties, which was verified by simultaneously measuring the chlorophyll conc…
Milankovitch forcing of Early Jurassic wildfires
2019
The Early Jurassic was characterized by major climatic and environmental perturbations which can be seen preserved at high resolution on orbital timescales. The Early Jurassic is a period of overall global warmth, and therefore serves as a suitable modern-day analogue to understand changes in the Earth System. Presently, Earth’s climate is warming and the frequency of large wildfires appears to be increasing. Recent research has indicated that Quaternary deposits reveal that wildfires respond to orbital forcings; however, to date no study has been able to test whether wildfire activity corresponds to changes over Milankovitch timescales in the deep past. A high-resolution astrochronology ex…
Interaction of radiation fog with tall vegetation
1999
Abstract A one-dimensional radiation fog model is presented. It is coupled with a second model to include the effects of tall vegetation. The fog model describes in detail the dynamics, thermodynamics, and microphysical structure of a fog, as well as the interactions with the atmospheric radiative transfer. A two-dimensional joint size distribution for the aerosol particles and activated fog droplets is used, the activation of aerosol particles is explicitly modeled. The implications of the presence of tall vegetation on the state of the atmosphere and on the evolution of radiation fog are stated. It is shown that the existence of tall vegetation impedes the evolution of radiation fog. The …
A one-dimensional simulation of the interaction between land surface processes and the atmosphere
1992
A one-dimensional soil-vegetation model is developed for future incorporation into a mesoscale model. The interaction of land surface processes with the overlying atmosphere is treated in terms of three coupled balance equations describing the energy and moisture transfer at the ground and the energy state of the vegetation layer. For a complete description of the interaction, the coupled processes of heat and moisture transport within the soil are included as a multilayer soil model. As model verification, successful reproductions of the observed energy fluxes over vegetated surfaces from the HAPEX-MOBILHY experiment in southwestern France and from the LOTREX-10E/HIBE88 field experiment in…
Long-term accuracy assessment of land surface temperatures derived from the Advanced Along-Track Scanning Radiometer
2012
Abstract The accuracy of land surface temperatures (LSTs) derived from the Advanced Along-Track Scanning Radiometer (AATSR) was assessed in a test site in Valencia, Spain from 2002 to 2008. AATSR LSTs were directly compared with concurrent ground measurements over homogeneous, full-vegetated rice fields in the conventional temperature-based (T-based) method. We also applied the new radiance-based (R-based) method over bare soil and water surfaces, where ground LST measurements were not available. In the R-based method, ground LSTs are simulated from AATSR brightness temperatures in the 11 μm band and radiative transfer simulations using surface emissivity data and atmospheric water vapor an…