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Andrzej Kaim and Przemysław Sztajner

ABSTRACT

Kaim, A. and Sztajner, P. 2012. Faunal dynamics of bivalves and scaphopods in the Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland. Acta Geologica Polonica, 62(3), 381- 395. Warszawa.

The environment at the Gnaszyn section - as deduced from bivalve and scaphopod dynamics - was controlled by the substrate consistency and possibly oxygen deficiency near the sediment-water interface and/or oxygen content fluctuations. The middle part of the section dominated by nuculoid and corbulid bivalves and Laevidentalium -type scaphopods probably reflects a soupy substrate and possibly oxygen deficiency in the sediment. Slightly coarser and better-oxygenated silts in the upper and lower parts of the section offered a less soupy substrate consistency, allowing the development of communities dominated by astartids, byssate bivalves, and Dentalium - and Plagioglypta-type scaphopods.

Open access

Mohamed Gliz, Boualem Remini, Djamel Anteur and Mohammed Makhlouf

Abstract

Located in the north west of Algeria, the watershed of Wadi El Hammam is threatened by water erosion that has resulted the silting of reservoirs at cascade: Ouizert, Bouhanifia and Fergoug. The objective of this study is to develop a methodology using remote sensing and geographical information systems (GIS) to map the zones presenting sensibility of water erosion in this watershed. It aims to produce a sensibility map that can be used as a reference document for planners. The methodology presented consists of three factors that control erosion: the slope, the friability material and the land use, which were integrated into a GIS. The derived erosion sensibility map shows three areas of vulnerability to water erosion: low, medium and high. The area of high vulnerability corresponds to sub-basin of Fergoug.

Open access

Maja Bryk

Ocena Szorstkości Powierzchni Agregatów Glebowych za Pomocą Analizy Obrazu

Open access

Anna Miechówka, Tomasz Zaleski and Elżbieta Kowalczyk

Abstract

The aim of the study was to determine soil-forming processes in soils formed from the Magura sandstones (Carpathian flysch) under wooded spruce Plagiothecio-Piccetum tatricum in the Gorce Mts., southern Poland. The research focused on distribution of non-silicate forms of iron and aluminum in soil profiles. The content of pyrophosphate, oxalate, and dithionite phases of iron and aluminum in the genetic horizons of four soil profiles was measured and selected pedogenic factors were calculated. Based on the obtained results podzolization and brunification are dominant soil-forming processes in the studied soils. The brunification effect was more common in the soils under the large share of Athyrium distentifolium, whereas podzolization predominates in the soils where Vaccinium myrtillus prevails in forest floor. Studied soils were classified as Dystric Endoskeletic Cambisol (Loamic, Humic), Dystric Cambisol (Siltic, Humic) and Skeletic Folic Albic Podzol (Arenic).

Open access

Karin Sowada

Abstract

During excavations in 1996 on a tomb in the Teti Cemetery at Saqqara by the Australian Centre for Egyptology (Macquarie University, Sydney, Australia), evidence of ancient weather events was revealed. The tomb belonged to the high official Inumin, who late in his career served as vizier of King Pepy I of the Sixth Dynasty. Over a metre of eolian sand sealed by extensive laminated silt deposits in the subterranean burial chamber was the result of a sustained dry windy period, followed by a short period of intense rainfall. These events are dated on stratigraphic grounds to the Late Old Kingdom - early First Intermediate Period. Evidence of the same weather event was recorded near the enclosure of Netjerykhet Djoser at Saqqara, which was dated by the excavators to the 23rd century BC

Open access

Barbara Stojek

Abstract

The purpose of this paper was the estimate of the substratum compaction in various soil types and under various conditions of use. The compaction characteristics were performed on the basis of bulk density of soil. It was performed on various types of soil, built of various materials, occurring in the vicinity of Płock. The soils are farming land. The greatest sub-stratum compaction was observed in arable lands, built of light loam, silt and loamy sand. The difference in bulk density between the layer at the depth of 25 – 35 cm and the adjacent horizons reaches 0.3 Mg per cubic metre. In soils used for green crops the substratum layer does not show a large difference between the adjacent layers, but the values of bulk density are equal to about 1.6 – 1.8 Mg per cubic metre already near the surface. Higher values of bulk density at the depth of 25 – 35 cm were observed in 68% of soils under investigation.

Open access

Gábor Sándor and György Szabó

Abstract

Soil profiles of the city centre of Debrecen were investigated in order to examine their properties and investigate the vertical distribution of heavy metals as a measure the anthropogenic activity. During the laboratory work the basic soil features were identified (texture, artefact content, pH, CaCO3, and amounts of organic matter). Furthermore, contents of Pb, Zn, Cu and Co in the soils were measured. Most of the metals showed a strong positive correlation with the humus content and the silt fraction. The soils of the city centre are exposed to a significant anthropogenic effect, therefore the original soil morphologies are usually difficult to identify. The soil profiles are greatly disturbed, which is traceable in the vertical distribution of certain soil features and metal contents.

Open access

Linda Olsvig-Whittaker, Margareta Walczak, David Jobse and Bertrand Boeken

ABSTRACT

The EBONE (European Biodiversity Observation Network project) asked the Israel Nature and Parks Authority to test methodology correlating patterns of species distribution with habitat in arid regions. A test of this methodology was conducted at the Avdat LTER site in the Negev Desert. Four square kilometers were mapped using the EBONE system of structural habitat mapping. Samples of vegetation, reptile and arthropod communities were taken using stratified random sampling of the mapped habitat polygons. Habitat type correlated poorly with species richness, but correlated well with community composition across all the taxonomic groups. We also found that the correlation of species composition to habitat type coincided with a gradient of substrate texture, from fine silt, sand, gravel and stones to large boulders and bedrock outcrops.

Open access

Janusz Urbański, Ryszard Oleszczuk, Andrzej Brandyk and Ewelina Zając

Abstract

This paper involves a comparative analysis of cross-sectional changes at selected reaches of a lowland river, flowing through the areas of mineral and organic soils. The comparisons were made at the background of design and execution assumptions from the period 1967–1971. Main processes, responsible for the observed changes of riverbeds in mineral soils (silting, conservation works) and organic soils (subsidence, disappearance of the peat deposit), were identified. In case of organic soils, the decrease of cross-sectional area by approximately from 30 to 60% was estimated in comparison to the original project assumptions, and the subsidence of river banks reached even 0.5 m in relation to the level determined in 1967. In the area of mineral soils, more considerable variability of cross-sectional area was noted along with minor changes of river banks elevation, that resulted most likely from the performed maintenance works.

Open access

Anna Bucała, Włodzimierz Margielewski, Leszek Starkel, Krzysztof Buczek and Valentina Zernitskaya

Abstract

The paper presents the analysis of organic and mineral sediments filling the depression, which developed over the landslide located at the slope (767–773 m a.s.l.) of Lubań ridge decscending to the Ochotnica river valley in the Polish Flysch Carpathians. The landslide formed in an early stage of the Subatlantic Phase (2490 ± 35 BP). The top of peat is dated at 1360 ± 50 years BP and is covered by 72 cm of clayey silts with some sandy intercalations, which indicate slopewash after deforestation. The pollen of ruderal plants and Cerealia (undiff.) reflect agricultural activity in the surroundings. The fragments of charcoal indicate the age of the forest clearance to the first half of the 17th century. The late forest clearance at the elevated north exposed slopes followed 200–300 years later in relation to the foundation of the village at the valley floor.