Search results for "35"
showing 10 items of 2413 documents
Shoreline Extraction and Change Detection using 1:5000 Scale Orthophoto Maps: A Case Study of Latvia-Riga
2015
Coastal management requires rapid, up-to-date, and
 correct information. Thus, the determination of coastal movements and its
 directions has primary importance for coastal managers. For monitoring the
 change of shorelines, remote sensing data, very high resolution aerial images
 and orthophoto maps are utilized for detections of change on shorelines. It is
 possible to monitor coastal changes by extracting the coastline from orthophoto
 maps. Along the Baltic Sea and Riga Gulf, Latvian coastline length is 496 km.
 It is rich of coastal resources and natural biodiversity.  Around 120 km of coastline are affected by
 significant coastal chang…
Studies on the zooplankton of the deep subalpine Lake Garda
1999
The specific composition and seasonal dynamics of the zooplankton of Lake Garda have been studied through monthly surveys in two annual cycles (December 1994-November 1995 and January-December 1997). The assemblage is largely dominated by Copipo-diaptomus steueri, a typical calanoid presently identified in deep (Garda, Iseo) and shallow lakes of NE Italy and in the hinterland of the central Adriatic region (Dalmatia and Marche Region). Cladocerans and the smaller rotifers represent a significant component of the zooplankton from spring to autumn. A re-examination of the results obtained in previous studies does not seem to demonstrate substantial shifts in the composition of the dominant sp…
Community response to environmental noise in Valencia
1990
Abstract In Valencia, Spain, 263 residents were interviewed at five different locations in order to investigate the subjective response to environmental noise in urban areas. External noise levels were measured over five consecutive days at each site. Noise levels were high in two of the selected sites ( L eq 24h about 75 dBA) and lower in the other two ( L eq 24h about 65 dBA). The fifth location had a night noise problem because of the presence of many leisure places (pubs, restaurants, etc.). The scores of the sample with their satisfaction with their neighbourhood were notably higher in the quiet than in the noisy areas (83% and 64% respectively). Road traffic and pub noise (in the fift…
The Influence of an Environment on the Content of Macro- and Microelements in the Tanacetum vulgare
2019
Tansy (Tanacetum vulgare L.) grows in moderate area of the northern hemisphere, in Poland – its range covers the whole country. It appears on the farm wastelands, by roadsides, on enbankments, river banks, forest lips and in open spaces. The present paper has faced the challenge of defining the influence of the environmental conditions on the mineral composition of Tanacetum vulgare leaves. The plants were picked in the blooming period from May to September 2017 in 12 natural environments of their growth and at different contamination levels. The dried and minced plant material was submitted to chemical analyses of the bio elements content (K, P, Cu, Zn, Mo) of leaves. A great variety was o…
The Influence of Urban Agglomeration on the Accumulation of Certain Heavy Metal Ions in Tansy (Tanacetum vulgare L.)
2020
Different compounds including toxic heavy metals ions have been used in various industrial branches for ages. Therefore, these compounds are nowadays often identified in the natural environment. Plants usually function like indirect transporters through which heavy metals, in the form of ions, infiltrate from the environment into the human and animals’ food chains. The present paper studied the influence of urban agglomeration on the accumulation of certain heavy metals in tansy. The content of heavy metals ions (Cr, Ni, Cd and Pb) was marked in the tansy leaves. Depending on the location of sampling, large variations in the heavy metal content were observed in the plant material. The resea…
Multi-elemental EDXRF mapping of polluted soil from former horticultural land.
2004
The distribution of major and trace elements was systematically investigated by use of energy dispersive X-ray fluorescence spectrometry (EDXRF) on a former horticultural soil. The purpose of the study was to combine mapping of soil element concentration levels with multivariate statistics for characterisation of soil metal pollution in relation to previous and present land use. A 1-ha study site was chosen from a former horticulture where a previous preliminary survey indicated increased concentration levels of toxic elements. The soil was sampled from the top 20 cm of the soil surface in a 10×10-m grid-like pattern covering the 1-ha study area. In addition, three soil profiles were studie…
Experimental test on the use of MS-222 for ostracod anaesthesia: concentration, immersion period and recovery time
2010
Anaesthesia of animals may be useful for different purposes, particularly for veterinary reasons or in experimental research, for manipulation or treatment of immobilized but alive animals. Its use in crustaceans is not uncommon, but it has never been described for Ostracoda. We provide brief and preliminary guidelines on the use of the tricaine mesylate (MS-222) on the widespread freshwater ostracod Eucypris virens and we show that this compound is an effective anaesthetic used as a bath treatment at minimum concentrations of 500 mg L-1. This value is considerably higher than that recommended for other aquatic animals like fish. Recovery time, ranging from 5 to 15 minutes, is mostly determ…
La relación entre toponimia urbana y topografía en la Ciutat Vella de Valencia: análisis mediante métodos cuantitativos y cualitativos
2017
El casco antiguo o Ciutat Vella de Valencia se caracteriza en apariencia por el escaso desnivel del terreno; sin embargo, algunos de sus topónimos describen o denotan un relieve accidentado que parece desmentir dicha impresión de planitud. Gracias a la tecnología LIDAR, capaz de detectar variaciones de centímetros en la altitud de la superficie terrestre, podemos comprobar si dichos orotopónimos se corresponden con superficies irregulares. Mediante métodos cuantitativos (LIDAR) y cualitativos (toponimia) se detectan y analizan desniveles del terreno, y se observa cómo estos han influido notablemente en la segregación social y en la distribución de los usos del suelo. València's Ciutat Vella…
Methodology for Calculating the Potential Maritime Wind Park Area by Taking into Account the Needs of Shipping Sector
2018
Renewable energy sources (wind energy, solar energy, hydroelectricity, ocean energy, geothermal energy, biomass and biofuels) are alternatives to fossil fuel that help to reduce greenhouse gas emissions, diversify energy supplies and reduce dependency on markets of unsustainable and volatile fossil fuels, particularly oil and gas. Wind energy is one of the renewable energy sources and is considered to be self-renewable as it is the result of the Sun’s activity. Using wind energy is a rapidly developing industry today, and more and more wind turbines are installed worldwide every year, land-based wind turbines being more widespread than offshore ones. In Latvia, spread of land-based wind par…
Wake and Turbulence Analysis for Wind Turbine Layouts in an Island
2018
There is a big wind energy potential in supplying the power in an island and most of the islands are off-grid. Due to the limited area in island(s), there is need to find appropriate layout / location for wind turbines suited to the local wind conditions. In this paper, we have considered the wind resources data of an island in Trøndelag region of the Northern Norway, situated on the coastal line. The wind resources data of this island have been analysed for wake losses and turbulence on wind turbines for determining appropriate locations of wind turbines in this island. These analyses are very important for understanding the fatigue and mechanical stress on the wind turbines. In this work,…