Non-marine invertebrate trace fossils from the Tertiary Calatayud-Teruel basin, NE Spain

Relatively diverse trace fossils made by insects, other arthropods and oligochaete worms occur in the Miocene lacustrine and marginal lacustrine deposits of the Calatayud-Teruel basin (NE Spain). They include the ichnospecies Celliforma isp., Celliforma? isp. A and B, Celliforma? aff. habari, Rosellichnus cf. arabicus, Spongeliomorpha isp., Labyrintichnus terrerensis n. igen. et isp., Taenidium barreti, Beaconites filiformis n. isp. and Polykladichnus aragonensis n. isp. Their taxonomic and ethologic interpretations and cross-cutting relationships permit to envisage new lines of evidence for reconstructing transitions from dry-ground terrestrial to moist-ground and subaqueous environments, related to episodic floodings in lacustrine ponds. These environmental transitions (related to external controls) are characterized by benthic community replacements, evinced by vertical successions of Termitichnus, Scoyenia and Mermia-like ichnofacies.

Investigation of salt migration in the ground saturated with a chloride-sulphate sodium-magnesium solution in freezing-thawing cycles**

Among the variety of objects in the permafrost zone, soils are encountered, including cryopegs – highly mineralized solutions that have excessive pore pressure. Generally, they have a negative impact, reducing the load-bearing capacity of the ground and causing corrosion of concrete and metal constructions. The study of cryopegs does not receive enough attention from Russian and foreign researchers, not least because of the peculiarities of the thermodynamic state they exist in, therefore detailed investigation of this cryologic object is required in the field and in laboratory conditions. In the presented research the authors study the mechanism of the migration of salt ions in pore water in an enclosed volume of ground during the freezing front movement. To do this, the authors developed an experimental unit and created a measuring unit where the studied moist ground is inserted. Temperature can be set on the opposite sides of the measuring unit. Controlling the extent and speed of temperature change provides a means to regulate freezing front movement (directed from top to bottom). After a number of freezing-thawing cycles salt compositions and concentrations are checked and measured in four intervals of sampling. As a result of the experiments a significant increase in concentration was found at opposite sampling points, and in particular at the beginning of the freezing front movement.

Occurrence of Corncrakes Crex crex in mosaic farmland landscapes in south-central Sweden – effects of habitat and landscape structure

SummaryMost studies of Corncrakes have been conducted in grasslands used for hay-cutting, and earlier hay-cutting has been suggested as the main cause of population decline in this species. Less is known about habitat preferences in relation to other land-uses and landscape structure. This paper investigated habitat composition and landscape structure in territories and at random sites in arable fields and meadows in south-central Sweden. Calling Corncrakes preferred sites with tall vegetation, moist ground, and locations close to ditches (55% of territories). Suitable conditions occurred on abandoned unmanaged wet meadows (31% of territories), mown wet meadows (14%), leys (30%) and non-rotational set-asides (15% of territories). Corncrakes avoided annual crops and other crops with short vegetation in the spring. Cutting of vegetation before mid-July was recorded in 21% of the territories and resulted in 100% abandonment of these sites. In contrast to many other ground nesting farmland birds, Corncrakes did not avoid forest edges (42% of territories within 100 m of edges). A strategy to conserve Corncrake populations should focus on maintenance of moist natural and sown grasslands (unmanaged or mown late) with tall vegetation and prevention of succession to woodland. Target areas should be in forested landscapes, because many other meadow birds that are more dependent on management (e.g. yearly mowing or grazing) prefer open landscapes.

V. An account of the fall of a meteoric stone the Cold Bokkeveld, Cape of Good Hope. By Thomas Maclear, Esq. F. R. S. &c. in a letter to Sir John F. W. Herschel, Bart. V. P. R. S. &c. &c. Communicated by Sir J. F. W. Herschel

Dear Sir John, A Meteor exploded on the 13th of October in the Cold Bokkeveld, with a noise so loud as to be heard over an area of more than seventy miles in diameter, in broad daylight, about half-past nine in the morning. It was seen traversing the atmosphere north-east of the point where it exploded sixty miles, of a silvery hue, the air at the time calm, hot, and sultry. The barometer chanced to be observed at Worcester, where the air was also calm and hot. It stood at the lowest point of its range, but, from the construction of the instrument, that point cannot be noted in inches unless by comparison with another, which I will endeavour to have done the first opportunity. The explosion was accompanied by a noise like that from artillery, followed by the fall of pieces of matter, of which I send you the largest and best specimen I have seen, procured by Mr. Watermeyer. Portions fell or were dispersed on the ground at the distance of an hour, or five miles from each other. Some falling on hard ground were smashed; others on moist ground plunged into the earth; and I am told that one piece made a hole as broad as three feet, and sunk deep. It is stated to have been so soft as to admit of being cut with a knife where it first fell; then it hardened, but I cannot learn anything as to its temperature at that moment. If the reports are correct, I estimate the original solid mass at five cubic feet, viz. the sum of all the portions that fell to the ground.