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Clues of climate change on the Alashan Plateau since the last glacial period (40 ka) are important for revealing the mechanism of desertification of middle-latitude deserts in the Northern Hemisphere (NH). Studies are still rare for the understanding of the specific relationship of climate changes between the Alashan Plateau and the global. Based on a systematic and comparative analysis of the existing research in China and the international academic community, this paper reviews the environmental evolution history of the Alashan Plateau since the last glacial period from the records of paleo-environment and geomorphological characteristics in different deserts of the plateau (e.g., Badanjilin, Tenggeli, and Wulanbuhe). From about 40 ka to the end of the last glacial maximum, the climate on the plateau was wetter than it is today, and to the end of the Pleistocene, the climate was generally dry and the aeolian activities were enhanced. However, the climate was arid during the whole last glacial period in the Wulanbuhe Desert, evidently different from the overall pattern of the plateau. The Tenggeli Desert was characterized by an arid climate in the early Holocene. The most controversial events for the Alashan Plateau are the drought events in the middle Holocene in the Badanjilin Desert. The role and impact of the westerlies and the East Asian Summer Monsoon (EASM) systems on the climate change of the desert and even the whole plateau is a vexed question that brings different views in different periods. There is still a lack of definite evidence representing the events of global environmental change that occurred on the plateau during the discussed period. The distinctive morphology of dune mountains and the distribution of sand dunes are mutually indicative of the direction and energy of wind systems on the plateau. It is suggested that appropriate wind energy is the significant key to the desertification in these middle-latitude deserts on the plateau. From a global-scale review of climate change, the desertification of the modern-scale sandy desert landscapes on the Alashan Plateau is generally related to the global glacial period and the cold and dry climate during the past 40 ka. [ABSTRACT FROM AUTHOR]

Understanding life history of natural forest and woodland is important as we need to prepare for, to cope with and to tackle problems associated with the ongoing global environmental changes. The present paper focuses on one of the world's terrestrial biomes, the arctic tundra, which is a type of biome where the tree growth is hindered by low temperatures and short growing seasons. A severe threat to tundra is global warming, which causes permafrost to melt affecting species survival, and which releases soil-bound carbon in the form of greenhouse gases. Tundra vegetation is composed of dwarf shrubs, sedges and grasses, mosses and lichens - a woodland type of vegetation dominated primarily by birch shrubs. The aim of this paper is to summarize and highlight my thirty three years of genetic studies of birch woodlands in Iceland, from the discovery of introgressive hybridization in birch and estimating the extent of introgression, to uncovering past hybridization events since the end of the last glaciation about 9000 years ago. The studies use different approaches, from cytogenetic and botanical, to molecular and palynological. The overall results show clearly that hybridization between B. nana and B. pubescens is widespread in Iceland; the resulting gene flow via introgressive hybridization is bi-directional; and that the process is continuous through time and space. Iceland could be considered a birch hybrid zone, harbouring genetic variation which may be advantageous in subarctic regions. However, waves of hybridization associated with climate warming could drive one of the species into extinction. [ABSTRACT FROM AUTHOR]

The paper presents a brief account of the temporal changes found in proportions of the mammal components in the diets of several species of predators (owls and carnivores) collected from various sites in Slovakia and originating in various periods (Late Pleistocene–Recent). The material collected from the Šarkanica Cave (Muráňska planina Mts.) contained bones in three layers, dated using the radiocarbon analysis (14 C) to 18,000–21,000 years BP (18–21 Ka), showing relatively small differences in composition of the fossil diet of Bubo scandiacus with predominance of Lasiopodomys gregalis (73.3%) and Chio- nomys nivalis (6.9%). A similar type of material from the Nový 3 Cave (Belianske Tatry Mts.), dated to the period of 30 Ka, contained more numerous remnants of Lemmus cf. lemmus and Sorex tundrensis. Undated samples from the Nový 1 Cave and from the Šarkania diera Cave (Súľovské skaly Mts.), which differ in their higher abundance of Dicrostonyx cf. gulielmi, are probably dated from the colder period of the last glacial maximum. Three samples from caves in the Veľká Fatra Mts. dated from the Late Pleisto- cene (Upper Dryas) originated from carnivores, with differences in relative proportions of predominant prey species: Chionomys nivalis (80.0%) and Lasiopodomys gregalis (14.3%), while remains of Cricetus cricetus (0.6%) also appear there. Two examples of differences in the diet composition of Strix aluco in the Veľká Fatra Mts. are present in samples dated to the Holocene period: natural development of forest fauna in the environs of Dolný Harmanec and anthropogenic influence in the form of three deforestation periods in the Tlstá massif near Blatnica (both Veľká Fatra Mts.). A sample set of the diet of Tyto alba dated >500 years BP from a church in Žilina is compared with a recent sample set of this owl diet from the Turčianska kotlina Basin and from the Danubian Lowland (Tekovské Lužany). The main difference lies in the greater proportion of the murid rodents and the relatively lower abundance of Microtus arvalis in the sample from the 16th century. Similar results were found comparing samples of Tyto alba diet, taken from a cave near Hatiny (Slovenský kras Mts.) and expected to be 100 years old, with more recent samples from the Košická kotlina Basin. The collection from the Hatiny Cave differs from the recent material in the presence of Sicista trizona and Alexandromys oeconomus. The recent samples of the diet of Bubo bubo taken from the Horné Považie Basin differ from the samples dated back more than 70 years ago by a high proportion of the genus Apodemus and a predominant incidence of frogs, while the old samples come from the period of the communist influence of the agricultural production causing serious environmental changes in the countryside (1950s) and as a result, a greater volume of large prey species, Rattus norvegicus, Arvicola amphibius, Lepus europaeus, and Erinaceus roumanicus. Since 1990, the availability of large prey for Bubo bubo has decreased due to the decline of livestock farming and a con- sequent successional overgrowing of pasture land by trees. [ABSTRACT FROM AUTHOR]

This paper introduces the reader to a special issue of articles that explores links and processes behind societal change, climate change and environmental change in a Holocene perspective in the Mediterranean region. All papers are, by purpose, co-authored by scientists representing different disciplines. The cross-cutting theme has been to reach beyond simple explanations of potential climate-society relationships and advance our understanding on how to improve research methods and theories in the field. The thirteen papers in this issue address these questions in three different ways, by i) conceptual/methodological approaches; ii) review papers; and iii) case studies. [ABSTRACT FROM AUTHOR]

Abandoned river channels may provide rich primary sources of palaeoenvironmental and cultural information elucidating landscape evolution, climate change, vegetation history and human impact, especially since the beginning of the Holocene epoch. However, although potentially an important resource, palaeochannels are not often recorded systematically and only rarely enjoy robust statutory protection (in the UK as Sites of Special Scientific Interest). In consequence, it is challenging to mitigate and manage this important geoarchaeological resource effectively within the UK planning framework. Whilst palaeochannels have long been recognised on aerial photographs and historic maps, the advent of airborne laser scanning (Lidar) and other remote-sensing technologies has provided a hitherto unforeseen opportunity to record such landforms and related features at a catchment scale. This paper provides a case study from the Nottinghamshire reach of the Trent Valley, where a desk-based methodology that is now being extended across the entire catchment has been developed for recording, geospatially locating and defining the attributes of observed palaeochannels. After outlining the methodology, we consider how this approach to resource management can aid archaeological research and future heritage management, especially in the light of predicted climate and environmental change. [ABSTRACT FROM AUTHOR]

Deserts and sandylands that are located in the semi-arid and arid regions in the middle latitudes of the Northern Hemisphere are usually regarded as environmentally sensitive change belts which respond to global climatic change. In northern China, activation or immobilization of sand dunes is mainly influenced by humid and dry variation and is related to stronger or weaker Asian monsoons. In this paper, the history of Holocene millennial-scale climatic and environmental change is reconstructed by the systematic analysis of the geochemical element contents and parameters, along with the OSL and C chronologies, from the different lithologies of the palaeosol-aeolian sand sequence in the south-eastern Mu Us Desert, northern China. Our results indicate that the region was dominated by a dry climate with intensive aeolian activity before 7.2 ka BP, and there was an optimal humid climate and fixed desert in 7.2-4.6 ka. Afterwards, the dune fields became mobile again as the effective humidity declined. Additionally, six dry events were discovered with times of ~7.2, 7.0-6.8, 6.6-5.7, 4.6-4.1, 3.7-3.5, and 3.3-2.5 ka, which were not only coincident with the intervals of millennial-scale weaker Asian summer monsoons, but also accordant with the cold events evidenced in the ice cores and deep-sea deposits of the high latitudes in the Northern Hemisphere. In general, the Holocene climatic and environmental changes had the characteristics of the 'monsoonal mode' and 'abrupt millennial-scale oscillation' in the Mu Us Desert. [ABSTRACT FROM AUTHOR]