The Vyazivok loess sequence from the Dnieper Plain, Ukraine, documents regional environmental changes during the late Pleistocene and Holocene. Pedological and palynological analyses and low-field magnetic susceptibility document changes from dense temperate forest during the last interglacial maximum to open, harsh, loess–steppe during the latest Pleistocene. The Vyazivok section overlies hillwash derived from a lower Pleistocene terrace and consists of two stratified soil complexes (Kaydaky and Pryluky; marine isotope stage [MIS] 5 equivalent) separated by a layer of eolian dust (Tyasmyn silt). The lower soils in both complexes formed within forest. These soils are overlain by the Uday (MIS4) and Bug (MIS2) loess units, which are separated by boreal soils of the Vytachiv (MIS3) complex. The coldest conditions within the record occurred in the youngest loess. Holocene soils cap the Bug loess. The Vyazivok section shows remarkable similarities with other classical loess sequences in western Europe, the Czech Republic, and Austria. The Kaydaky, Pryluky, and Vytachiv deposits, correlate with the PKIII, PKII, and PKI soil complexes, respectively, of the Czech Republic. The Tyasmyn and Prylyky silt layers correspond to marker horizons from central Europe.

Based on multivariate analysis of mollusk assemblages and magnetic susceptibility of the Eustis section in western Nebraska, the climate of the Peoria loess steppe was relatively mild and, in terms of annual precipitation, relatively moist during the advance stages of Woodfordian ice. It was cold and dry during ice retreat. The diversity and composition of mollusk species indicates that the extreme cold and dry climate was reached during the late phase of Peoria time, in mollusk zone MZ3. Although soil moisture during the growing season at that time was high, the growing season was short and annual precipitation totals were low. Low values of magnetic susceptibility imply relatively rapid dust deposition during this interval, Judging from the current ecological tolerance of the species, no closed forest existed in the area. Only scattered shrubs or isolated tree stands may have been present. The late Peoria MZ3 assemblage compares favorably with the Columella fauna of Europe. In contrast, the early Peoria mollusk assemblages MZ1 and MZ2 compare well with the European pleniglacial Pupilla associations. Based on available 14 C dates from the studied region and on assumed relation of magnetic susceptibility to sedimentation rates, the estimated age of the MZ1 and MZ2 zones is 24,000 to 16,000 yr, whereas that of MZ3 is 16,000 to 12,000 yr.

Two brown algae, Pelvetia canaliculata and Laminaria saccharina, from the higher and lower mediolittoral belts respectively, have been tested for their capacity to overcome high-light stress in water and in air (in both fully hydrated and desiccated states). When exposed to supersaturating light irradiance in water, the two species developed non-photochemical quenching of fluorescence (NPQ) which was correlated with an increase in the de-epoxidation ratio (DR) of the xanthophyll cycle carotenoids (violaxanthin, antheraxanthin and zeaxanthin) and was followed by a slower decrease in oxygen evolution. NPQ reached values of up to 9 in P. canaliculata but only 4·5 in L. saccharina, at DRs of 0·65 and 0·5, respectively. In air, the xanthophyll cycle was also operative but the efficiency of de-epoxidation decreased linearly with the degree of hydration of the thallus. Photoprotection capacities in air also appeared higher in P. canaliculata than in L. saccharina, probably due to the higher molar content of the xanthophyll cycle pool size relative to chlorophyll a (Chl a) in the former (nearly double of that L. saccharina at 19 carotenoid molecules per 100 Chl a), which may be associated with a higher DR at the same level of desiccation. The concomitant higher accumulation of zeaxanthin in P. canaliculata might divert a higher percentage of the incident energy from the reaction centres, as demonstrated by the levels of NPQ, with steady-state fluorescence reduced to below the initial F0 level. Such differences, together with the unequal resistance to desiccation of the operation of the xanthophyll cycle, should be considered as possible factors responsible for the distribution for these two species on the shore.