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Regionalna wymowa procesów antropogenizacji regionu środkowej Obry na podstawie badań osadów jeziora Wonieść

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Hildebrandt-Radke I. , Spychalski W. , Lutyńska M.

Landform Analysis

2011

tom Vol. 16

92-97

The study was aimed at anthropogenization processes of the Kościan Plain. They are noticeable in local palynological diagrams (eg. at the archaeological site in Bruszczewo) as well as on settlement maps of the Polish Archaeological Record Project. The goal was to determine whether the processes were perceptible also in a regional scale, in deposits of the biggest water body in the examined area, located 15 km to the east from Bruszczewo. Anthropogenic participation in changes of plant cover is clearly visible in the local diagram from Bruszczewo. While compared with the mentioned, anthropogenic influence in deposits of Wonieść Lake is rather inconspicuous. In the Neolithic and Early Bronze Periods, percentage of herbaceous plants (amount of grasses and herbs) maintained the level of 10%. Increase in NAP is marked not earlier than in the Roman Iron Age, and then from the Early Middle Ages until the present time (Dörfler, to be published soon). Comparison of palynological results to sedimentological analyses indicates that periods of increased values of CerealiaandPlantago lanceolataindices are correlated with inflow of mineral material to lacustrine water body. Larger fractions were observed there i.e. fine- and medium-grained sands, and even gravels as well as organic matter. In the geochemical record for the same periods, an increased percentage of trace elements can be visible (however their distinctive escalation is manifested not earlier than in the Middle Ages). These changes are accompanied by intensified eutrophication index (phosphorus percentage) as well as by occurrence of diatoms, which prefer eutrophic conditions.

Geochemical Analysis of Coastal Sediments near Larache and Moulay Bousselham, Morocco

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El Idrissi S. , Labriki A. , Sadiki M. , Akhlidej N. , Bounouira H. , Said S. , Amsil H. , Didi A. , Aarab I. , Chakiri S.

2024

tom Vol. 25, iss. 8

221--231

The aim of this study is to identify the main pollutants and evaluate the mechanisms of sediment transport from land to sea. This goal is justified by environmental pollution in the area associated with dredging and port activities. The objective is planned to be achieved by investigating the geochemical behavior of major and trace elements in fourteen surface sediment samples collected along the Moroccan Atlantic coast, from the mouth of the Lukkous River to the coast between the cities of Larache and Moulay Bousselam. k0-standardization method of neutron activation analysis using neutrons of the Moroccan Triga Mark II research reactor at the National Centre for Nuclear Energy, Science and Technology, has been used for analysis of collected sediment samples. The enrichment factor analysis revealed high levels of arsenic and chlorine, along with significant calcium enrichment, were found along the Atlantic coast. The enrichment factors (FE) for arsenic and chlorine are in the range of 20 < FE < 40, and for calcium, the FE is in the range of 5 < FE < 20. Conversely, some elements exhibited little to no enrichment, suggesting a crustal origin. PCA helped in synthesizing these findings, providing a clearer understanding of the spatial variations in sediment composition based on their multi-elemental signatures. The research examines surface sediments along the Moroccan Atlantic coast, revealing current contamination levels and geochemical behavior. These findings, applicable to similar coastal environments, are crucial for monitoring and managing sediment quality, especially in areas affected by erosion. Additionally, dredging and port activities in this region significantly disturb the sediments, resuspending contaminants and altering sediment composition, which further exacerbates pollution issues. This study offers a comprehensive geochemical characterization of coastal sediments in Morocco, enhancing understanding of sediment contamination and geochemical processes, with implications for environmental protection and sustainable marine resource management.

Zapis procesów prehistorycznej antropopresji w otoczeniu stanowiska archeologicznego w Bruszczewie (centralna Wielkopolska) na podstawie badań osadów rynny glacjalnej Samicy

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Hildebrandt-Radke I. , Janczak-Kostecka B. , Spychalski W.

Landform Analysis

2011

tom Vol. 16

87-91

The sedimentological, geochemical and diatomological research into the core taken from the fossil lake located in the glacial channel of Samica river prove the increasing anthropogenization of the landscape in the microregion surrounding the settlement in Bruszczewo. Anthropogenic indices of the Early Bronze Period in the palynological research include: high decline in the percentage of tree pollens caused by deforestation, indicators of grazing animals and farming as well as noticeable eutrophication of the lake (fungal spores and algae thriving on dung, droppings and excrement). In the sedimentological research, cultural layers correspond with accelerated mineral sedimentation in the basin (mediumand fine-grained sands). Each time it is preceded with organic sedimentation (from humus levels). Above results might signify the initiation of erosion-denudation processes in the catchment, settled and economically exploited by individual cultural groups. Results of the anthropogenic activity are visible also in the geochemical composition of the deposits. Cultural layers are marked with increased percentage of heavy metals, while the Cu : Pb : Zn ratios suggest their anthropogenic character. Additionally, the increase in phosphorus percentage confirms eutrophication of the basin in the settlement periods, that is in the Early and Late Bronze, and Early and Roman Iron Ages.