The genesis of some types of patterned ground, including hummocks, frost boils and sorted stone circles, has been attributed to differential frost heave (DFH). However, a theoretical model that adequately describes DFH has yet to be developed and validated. In this paper, we present a mathematical model for the initiation of DFH, and discuss how variations in physical (i.e. soil/vegetation prop...

The agricultural sector in Poland is of considerable social and economic importance for the nation. Climate variability and change are of primary relevance to this largely climate-dependent sector. Changes in seven temperature-related agroclimatic indices (lengths of the growing season and of the frost-free season, days of occurrence of the last spring frost and of the first autumn frost; and a...

Abiotic stress experienced by autumn-sown crops during winter is of great economic importance as it can have a severe negative impact on yield. In this study, we investigated the genetic architecture of winter hardiness and frost tolerance in triticale. To this end, we used a large mapping population of 647 DH lines phenotyped for both traits in combination with genome-wide marker data. Employi...

Foliar frost resistance of three endemic New Zealand land trees, Nothofagus menziesii (Hook. f.) Oerst. (Fagaceae), Pittosporum eugenioides A. Cunn. (Pittosporaceae) and Griselinia littoralis Forst. f. (Cornaceae), was examined as the trees hardened from late summer to midwinter in a lowland forest site. The lowest temperatures causing 50% damage (LT(50)) occurred in late winter and were simila...

The relationship between the water relations of six olive cultivars exposed to different soil temperatures (14 ± 0.1, 9.9 ± 0.1 and 5.8 ± 0.2°C) and their inherent frost resistance (as determined by two different methods) was investigated. Soil chilling was achieved by introducing pots of olive plants into water baths. The water relations of these plants were compared to those of plants kept un...

Miscanthus × giganteus grown in cool temperate regions of North America and Europe can exhibit severe mortality in the year after planting, and poor frost tolerance of leaves. Spartina pectinata (prairie cordgrass), a productive C4 perennial grass native to North America, has been suggested as an alternative biofuel feedstock for colder regions; however, its cold tolerance relative to M. × giga...

Nonsorted circles are relatively barren patterned-ground features common in most arctic tundra regions. We studied how vegetation changes on nonsorted circles might affect cryogenic processes, which is of relevance as arctic vegetation responds to climate change. Twenty-eight circles at a moist nonacidic tundra site in northern Alaska received one of four treatments: (a) vegetation removal; (b)...

Most studies of evolutionary responses to climate change have focused on phenological responses to warming, and provide only weak evidence for evolutionary adaptation. This could be because phenological changes are more weakly linked to fitness than more direct mechanisms of climate change impacts, such as selective mortality during extreme weather events which have immediate fitness consequenc...

PREMISE OF STUDY Leaf shape is predicted to have important ecophysiological consequences; for example, theory predicts that lobed leaves should track air temperature more closely than their entire-margined counterparts. Hence, leaf-lobing may be advantageous during cold nights (∼0°C) when there is the risk of damage by radiation frost (a phenomenon whereby leaves fall below air temperature beca...

[1] In mountainous landscapes the role of periglacial processes in producing sediment is poorly defined, despite evidence of abundant talus slopes. Ice growth in rock has long been recognized as an efficient erosion mechanism, but the effects have not been readily applied to landscape evolution in response to tectonic and climatic forcing. Here, we quantify how and where ice-driven mechanical e...