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Earliest cereal cultivation in Egypt recorded in the Faiyum Oasis lake deposits and its palaeoclimatic context

Welc Fabian, Marks Leszek, Milecka Krystyna

Geological Quarterly

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2023

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Vol. 67, No. 2

art. no. 21

EN

We determine the beginning of the Neolithic farming in northern Egypt, based on analysis of core FA-1 of lake deposits in the Faiyum Oasis in northern Egypt. Regular lamination of the early Middle Holocene lake deposits, supported by radiocarbon dating and pollen analysis, indicates the earliest occurrence of domesticated cereals at ~7.8 cal ka BP in this region. The appearance of cereals in the Faiyum region was possible due to fundamental restructuring of regional climatic conditions caused by the changing atmospheric circulation in the eastern Mediterranean region. Stronger northwestern winds were accompanied by increased precipitation in winter and enabled 3 farming phases in the Faiyum Oasis at 7.8–7.6, 7.4–7.2 and 7.0–6.8 cal ka BP, separated by arid episodes with predominant southern winds. Most probably, cereal cultivation concentrated inside local wadis to the north of the lake and was rainfall-dependent. Therefore, early Egyptian farming did not develop based on irrigation systems as commonly thought, but was rain-fed, this being possible due to marked climate change at the beginning of the Middle Holocene.

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Metagenomic Analysis Reveals Microbial Communities in Lake Qarun – Egypt

Yosef Mahmoud Mohamed, Elrefy Ali Mohamed, Elfeky Fawzy Ali

Journal of Ecological Engineering

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2022

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Vol. 23, nr 2

70--76

EN

Characterization of water quality in Lake Qarun indicated that the water is very poor for irrigation and aquatic life. At the same time, the bacterial community was represented mainly by five bacterial phyla with different proportions: Firmicutes (53%), Proteobacteria (33%), Bacteroidetes (7%), Actinobacteria (5%) and Thermi (1%). Furthermore, metagenomes prediction of bacterial communities using PICRUSt indicated important functional gene families associated with metabolism, environmental information, genetic information processing, and cellular processes. It is worth noting that Benzoate degradation had the highest average relative abundance, followed by aminobenzoate degradation among 18 individual KEGG pathways from xenobiotics biodegradation and metabolism which showed higher relative abundance. The obtained data indicate that a different source of pollution in Qarun Lakes has an impact on the bacterial community’s structure, as well as the biota and is expected to cause health problems.

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Molluscs and ostracods of the Qarun Lake: preliminary report from FA-1 core in Faiyum Oasis, northern Egypt

Szymanek M.

Studia Quaternaria

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2017

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Vol. 34, Nr 1

39--45

EN

A research was conducted on the Holocene lake sediments from the full-cored FA-1 drilling at the southern shore of the Qarun Lake in the Faiyum Oasis in northern Egypt. Altogether 10 taxa of molluscs and 8 taxa of ostracods were identified in the examined deposits, with total amounts of 768 and 2872 individuals, respectively. The fauna was investigated with palaeoecological purpose and allowed for preliminary reconstruction of sedimentary environment in the lake. The occurrence of Valvata nilotica Jickeli, 1874 and Gomphocythere sp. in the lower part of the core and a low proportion of carapaces (2.4–28%) indicated freshwater and higher-energy conditions, respectively. Rapid expansion of Cyprideis torosa (Jones, 1850) at a depth of 18 m could point to very short saline episode in the lake. The increase in salinity and drop of water level were evidenced in the uppermost part of the core (4–3.5 m), when the lake was dominated by Hydrobia ventrosa (Montagu, 1803), Cerastoderma glaucum (Poiret, 1789) and C. torosa. The steady sedimentation in a shallow lake was also supported by considerable amount of complete ostracod carapaces (45%). The faunal assemblage and smooth valves of C. torosa suggested salinity of 14–25‰.

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Diatom stratigraphy of FA-1 core, Qarun Lake, records of Holocene environmental and climatic change in Faiyum Oasis, Egypt

Zalat A. A., Marks L., Welc F., Salem A., Nitychoruk J., Chen Z., Majecka A., Szymanek M., Chodyka M., Tołoczko-Pasek A., Sun Q. L., Zhao X., Jiang J.

Studia Quaternaria

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2017

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Vol. 34, Nr 1

61--69

EN

This study evaluates changes in the environmental and climatic conditions in the Faiyum Oasis during the Holocene based on diatom analyses of the sediment FA-1 core from the southern seashore of the Qarun Lake. The studied FA-1 core was 26 m long and covered the time span ca. 9.000 cal. yrs BP. Diatom taxa were abundant and moderately to well-preserved throughout the core sediments. Planktonic taxa were most abundant than the benthic and epiphytic forms, which were very rare and sparsely distributed. The most dominant planktonic genera were Aulacoseira and Stephanodiscus followed by frequently distribution of Cyclostephanos and Cyclotella species. The stratigraphic distribution patterns of the recorded diatoms through the Holocene sediments explained five ecological diatom groups. Thesegroups represent distinctive environmental conditions, which were mainly related to climatic changes through the earlyand middle Holocene, in addition to anthropogenic activity during the late Holocene. Comparison of diatom assemblages in the studied sediment core suggests that considerable changes occurred in water level as well as salinity. There were several high stands of the freshwater lake level during humid, warmer-wet climatic phases marked by dominance of planktonic, oligohalobous and alkaliphilous diatoms alternated with lowering of the lake level and slight increases in salinity and alkalinity during warm arid conditions evident by prevalence of brackish water diatoms.

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Preliminary report on unique laminated Holocene sediments from the Qarun Lake in Egypt

Marks L., Salem A., Welc F., Nitychoruk J., Chen Z., Zalat A., Majecka A., Chodyka M., Szymanek M., Tołoczko-Pasek A.

Studia Quaternaria

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2016

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Vol. 33, Nr 1

35--46

EN

The Lake Qarun (Faiyum Oasis, northern Egypt) is a relic of the much larger Holocene lake. Past lake levels and extensions were reconstructed, based on setting of archaeological sites scattered along northern paleoshores of the ancient lake. However, geoarcheological works did not yield enough data to establish continuous environmental history of the lake. A deep drilling FA-1 on the southeastern shore of the lake, performed in 2014, supplied with a core, 26 m long that is the one of the longest lake sediment cores in northeastern Africa. The basal section of the core consisted of thin-laminated diatom marly deposits, underlain at the Late Pleistocene/Holocene boundary by coarse-grained sands. The sediment lamine were quite well developed, especially in the lower part of the core. Preliminary results indicated annually deposited sediment sequence with seasonality signals provided by microlamine of diatoms, calcite, organic matter and clastic material. Early Holocene varved sediments from the Faiyum Oasis supplied with exceptional paleoenvironmental data for northeastern Africa, which enriched a record from previous logs drilled at the southwestern margin of the Qarun Lake.