Distribution of Steranes and Triterpanes Biomarkersas Indication of Depositional Environment and Maturity of Sargelu and Kurrachine Formations in Different Wells Northern Iraq

Eight cuttings samples were obtained from Sargelu and Kurrachine formations in different wells at different depths to detect steranes and triterpanes biomarkers as an indicator of the depositional environments and thermal maturity of organic matter. This was accomplished using GC-MS technology. The diasterane/sterane ratio showed low ratios in analyzed samples (BJS2, JKS3, BJK1, JKK4, JKK7) as in most marine carbonate sources, while algal-bacterial organic matter contribution for the samples analyzed based on the predominance of C23 tricyclic relative to the C19 tricyclic terpene and the C23 tricyclic greater than C24 tricyclic terpane. The Gammacerane index indicated that normal salinity conditions during depositions. The biomarkers related to maturation such as diasterane/sterane, Ts/(Ts+Tm), and C29Ts/C29 hopane show that the organic matter in Ain Zalah well (Sargelu Formation) is within early mature (oil window).

Fossil gastropods Campanile lachesis Bayan, 1870 from the upper Eocene of the Eastern Rhodopes (Bulgaria)

The subject of this study is the description of eight specimens of fossil gastropods Campanile lachesis Bayan, 1870, family Campanilidae, from the fund of the Regional Museum of History in Kardzhali. They were found in the area of the village of Gorna Krepost, Kardzhali Municipality, at the eastern foot of the Archeological Complex Perperikon, in the upper Eocene (Priabonian) limestone layers of the so-called Beli Plast Rhyodacite Complex. The paleoecological traits of the present fauna give ground to infer that this was a very shallow reefal environment with a rocky substrate sandy bottom, overgrown with algae, and the water was warm, with normal salinity.

Effect of Planting Methods and Gypsum Application on Yield and Water Productivity of Wheat under Salinity Conditions in North Nile Delta

Salinity and water shortage are the most important factors limiting crop productivity, so increasing the productivity of salt-affected soils is important to address the global food gap. Two field experiments were conducted under typical farm conditions in the North Nile Delta to study the effect of planting methods and gypsum application on wheat yield and water productivity under a range of water and soil salinity levels. In the first experiment, wheat was treated with gypsum (25%, 75%, and 100% gypsum-requirement) with moderate or high salinity in soil and water. The second experiment was conducted for two seasons at two sites to test three planting methods (flat, 60-cm furrows, and 120-cm raised-beds) under normal or high salinity levels of both soil and water. The results showed that gypsum alleviated the hazardous effects of salinity stress on grain yield. Raised furrows or beds under higher salinity levels increased soil salinity, and soil salinity was slightly increased with flat plots. Higher yields, water savings, and water productivities were achieved with raised furrows or beds under normal salinity. To improve yield under normal salinity conditions, raised beds are the recommended planting method. Furthermore, gypsum application in cultivated fields can mitigate the negative effects of salinity stress.

A new molluscan assemblage from the pre-evaporitic Messinian of Crete (Greece)

<p>The Messinian Salinity Crisis (MSC) was an environmental perturbation with dramatic environmental consequences that greatly affected marine organisms. Messinian deposits are found in several locations around the Mediterranean, but few offer marine faunas rich in molluscs. A section near Heraklion, central Crete, has provided new material that contains a well preserved and rich molluscan fauna that includes many micromorphic species. The section is of early Messinian age, belongs to Agios Miron Formation, and bears several layers of fossiliferous marly sands.</p><p>Molluscs from a fossiliferous bed of the section are presented here for the first time. Gastropods and bivalves are most common, but scaphopods and chitons are not infrequent. The assemblage seems to be composed of transported elements from nearby environments and the most frequent species are present in comparable abundances for gastropods and bivalves. The gastropod fauna is represented by <em>Bittium</em> sp. and <em>Gibbula </em>sp., accompanied by <em>Diodora</em> cf. <em>graeca</em>, <em>Turritella</em> sp., <em>Jujubinus</em> sp., species of Pyramidellidae and rarer <em>Homalopoma</em> sp. and Haliotis sp. The presence of <em>Bittium</em> sp. together with <em>Jujubinus</em> sp. suggests vegetated environments. Bivalves are represented by species dwelling mostly in sandy environments such as <em>Glycymeris</em> cf. <em>inflata</em> (also occurring in larger specimens), <em>Spisula</em> sp., <em>Timoclea</em> sp. and various cardiids. Exceptionally well-preserved chitons indicate the presence of hard substrates such as rocks, pebbles or roots of seagrass beds. This is confirmed by the presence of the gastropods <em>Diodora</em> cf. <em>graeca</em> and <em>Haliotis</em> sp.</p><p>The assemblage points towards normal salinity shallow marine conditions of sandy bottoms with patches of seagrass-type vegetation before the onset of the MSC.</p>

Ecotypes of Aquatic Plant Vallisneria americana Tolerate Different Salinity Concentrations

Increased salinity caused by saltwater intrusion or runoff from de-icing salts can severely affect freshwater vegetation and deteriorate aquatic ecosystems. These habitats can be restored with freshwater ecotypes (locally adapted populations) that tolerate above-normal salinity. Vallisneria americana is a prominent species in many freshwater ecosystems that responds differently to abiotic conditions such as substrate composition and fertility, so, in this study, we evaluated the effects of salt stress on 24 ecotypes of V. americana. Instant Ocean aquarium salt was used to create saline solutions (0.2 to 20.0 parts per thousand (ppt)), then plants were abruptly exposed to these solutions and maintained in these concentrations for five weeks before being visually assessed for quality and destructively harvested. Analysis of variance and nonlinear regression were used to calculate LC50 values—the lethal concentration of salt that reduced plant biomass and quality by 50% compared to control treatment. Growth rate and visual quality varied significantly among ecotypes, and ecotypes that were most and least sensitive to salt had 50% biomass reductions at 0.47 and 9.10 ppt, respectively. All ecotypes survived 10.0 ppt salinity concentration but none survived at 20.0 ppt, which suggests that the maximum salinity concentration tolerated by these ecotypes is between 15.0 and 20.0 ppt.

Ecotypes of Aquatic Plant Vallisneria americana Tolerate Different Salinity Concentrations

Increased salinity caused by saltwater intrusion or runoff from de-icing salts can severely affect freshwater vegetation and deteriorate aquatic ecosystems. These habitats can be restored with freshwater ecotypes (locally adapted populations) that tolerate above-normal salinity. Vallisneria americana is a prominent species in many freshwater ecosystems that responds differently to abiotic conditions such as substrate composition and fertility, so in this study we evaluated the effects of salt stress on 24 ecotypes of V. americana. Instant Ocean aquarium salt was used to create saline solutions [0.2 to 20.0 parts per thousand (ppt)], then plants were abruptly exposed to these solutions and maintained in these concentrations for 5 weeks before being visually assessed for quality and destructively harvested. Analysis of variance and non-linear regression were used to calculate LC50 values – the lethal concentration of salt that reduced plant biomass and quality by 50% compared to control treatment. Growth rate and visual quality varied significantly among ecotypes, and ecotypes that were most and least sensitive to salt had 50% biomass reductions at 0.47 and 9.10 ppt, respectively. All ecotypes survived 10.0 ppt salinity concentration but none survived at 20.0 ppt, which suggests the maximum salinity concentration tolerated by these ecotypes is between 15.0 and 20.0 ppt.

Měkkýší fauna (Gastropoda, Bivalvia) z lokality Mušlov (vídeňská pánev)

The Mušlov locality is situated 3.5 km ESE from the town of Mikulov and it is a part of the Vienna Basin. On the locality a profile rich in shallow-water middle Miocene (Badenian) fauna was uncovered. Its substantial part was deposited in fine-grained calcareous sand, to a lesser extent the fauna also occurred in pebbles and blocks of gray algal limestones. Mainly stone cores with calcareous and degrading shells were found in the limestones, while in the calcareous sands the fossils were well preserved. A rich set of small fauna from fine-grained sand was obtained by washing of samples. There have been determined 73 species of Gastropoda and 25 species of Bivalvia. The most abundant species of gastropods are Tricolia eichwaldi, Rissoina podolica, Bittium reticulatum, Gibbula aff . umbilicalis, Jujubinus striatus, Neritina picta and Turritella bicarinata. Among bivalves the most abundand species are Cardites partschi partschi and Linga columbella. Quantity and degree of conservation of fauna indicate minimal transport and slow sedimentation on the sea floor. Based on the found species, the fauna was mainly bound to a fine-grained substrate but there were also species that preferred the solid substrate. The abundant occurrence living on algal species is evidenced by their rich stands. The fauna lived in the shallow sea with a good oxygenation and a normal salinity. The occurrence of some species documents a warm sea between 20–28 °C.

Oligocene turbidite fans of the Dukla Basin: New age data from the calcareous nannofossils and paleoenvironmental conditions (Cergowa beds, Polish–Slovakian borderland)

Calcareous nannofossils found in the Cergowa beds of the Dukla and Fore-Dukla tectonic units in the Outer Carpathians indicate a time of deposition in the range of the NP23–NP24 nannoplankton zones of the Lower Oligocene. Nannoplankton assemblages reflect the paleoecological changes at the Eocene–Oligocene transition from: (i) a greenhouse to an icehouse climate; (ii) brackish to normal salinity suggesting open sea conditions, which were controlled by the Paratethys Basin closure followed by opening and connection with the Tethyan Ocean. The absence of nannofossils of NP25 zone, but their presence in the tectonic windows between 40 and 80 km to the west, shows that deposition of the Cergowa beds in the western part of the basin lasted longer than in the east. Occurrences of nannofossils indicating zones NP16 and NP21, found in the uppermost mudstone-rich parts of studied sections, may prove the remobilization and redeposition of sediments of this stratigraphic age. Potentially, eroded material could be derived from some of the following lithostratigraphic units: NP16 — the Hieroglyphic beds, Przybyszów sandstones and Upper variegated shales; NP21 — the Globigerina marls, Mszanka sandstones and sub-Chert marls and shales and/or fine-grained equivalent of these units. Reworked specimens derived from the older Mesozoic strata occur occasionally in various samples.