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In this paper, we presented a reply to the comments on modern pollen rain and interpretations about the Last Glacial Maximum (LGM) by D’Apolito et al. Carajás may be considered as a micro-hotspot of plant endemism, mainly related to edaphic conditions and presence of different micro-habitats for canga vegetation into ironstone domains. These plants developed several survival strategies, including morphological and physiological adaptations, which is difficult for comparisons with any other distinct biomes or ecosystems. Furthermore, inaccurate interpretation of pollen taxa and habitat types by the previous palynological studies in Carajás, which are keys points presented in Guimarães et al., were not questioned by D’Apolito et al. Therefore, incomplete pollen database, uncertainties about pollen descriptions and plant–pollen habitat, poor knowledge about pollen production and dispersion in edaphically conditioned areas, as well as missing of multiproxy evidences about geology, geomorphology, faciology, and geochemistry can make LGM interpretations a very challenging task. This can produce more noises than reliable signals of paleoclimate changes. [ABSTRACT FROM AUTHOR]

Assessment of the wild or cultivated origin of Olea europaea L. during the middle to late Holocene according to pollen analyses is of palaeoecological and evolutionary interest as olive is thought to be one of the earliest cultivated trees and is still one of the most important fruit trees of the eastern Mediterranean. This paper considers data from the Bronze-Iron Age harbour-town, Tell Tweini, of the Ugarit Kingdom, in the Syrian coastal lowland near Jableh (17 m a.s.l.) and from the Hellenistic-Roman Moatra-Bereket (1410 m a.s.l.), in the territory of Sagalassos, in Turkey's western Taurus Mountains. Both of these sites have recorded the rise and collapse of early eastern Mediterranean urban systems from 4200 to 1600 cal. yr BP. The Syrian data suggest that the Olea pollen-type originated from wild varieties during the Bronze and Iron Ages despite archaeological evidence for olive cultivation in the northern Levant. For Turkey, the results of the pollen-numerical analyses support the existing archaeological evidence of a wealthy oleoculture in Hellenistic and Roman Anatolia and suggest important anthropogenic pressures on local ecosystems. [ABSTRACT FROM AUTHOR]

The Gunditjmara people developed a socio-economic system based on the modification of wetland ecosystems associated with the Mt Eccles lava flow primarily for sustainable production and management of the highly nutritious shortfin eel (Anguilla australis). This paper examines the environmental history of these landscapes since their inception about 30 000 years ago, through palaeoecological analysis of sediment cores from associated lakes and swamps, in order to contribute to an understanding of the causes and timing of cultural transformation. Two records cover the whole of the 30 000 year history of the landscape while two others provide evidence of change within the Holocene. A great deal of variation within the landscape is revealed, both temporally and spatially, with opportunities for human exploitation through the whole recorded period. Although most features of the records can be explained by natural landscape development and climate change, some human modification can be suggested from around the Pleistocene-Holocene transition while more obvious indications of management relating to eel aquaculture are evident from about 4000 cal. yr BP that appear to include adaptations to the onset of a drier and more variable climate. The study has implications for the explanation of intensification of settlement in Australia more generally within the mid to late Holocene. [ABSTRACT FROM AUTHOR]

Pollen analysis of a 48 m AMS radiocarbon-dated sediment sequence from the Guadiana estuary provides the first record of Lateglacial and Holocene vegetation history in the Algarve province of Portugal. This paper focuses on the record of terrestrial pollen taxa, which document a series of forest expansions and declines during the period 13 000 cal. BP to 1600 cal. BP and provide insights into climate evolution in southwestern Iberia. The main vegetation phases identified in the Guadiana valley are (1) Lateglacial interstadial (Allerød) forest with Quercus and Pinus under a temperate, moist, continental climate; (2) a Younger Dryas forest decline (Quercus) and expansion of pinewoods, xeric scrub and open ground habitats (with Juniperus, Artemisia, Ephedra distachya type, Centaurea scabiosa type) under arid and cold conditions; (3) an early Holocene forest/scrub/open-ground vegetation mosaic developing under a warm, dry and continental climate; (4) a maximum of Quercus forest and thermomediterranean evergreen taxa (Olea, Phillyrea, Pistacia) reflecting a warm, moist oceanic climate between c. 9000 cal. BP and c. 5000 cal. BP; and (5) the expansion of shrublands with Cistaceae and Ericaceae under a drier climatic regime and increasing anthropogenic activity since c. 5000 cal. BP. Holocene episodes of maximum climatic aridity are identified in the record of xerophytic taxa (Juniperus, Artemisia, Ephedra distachya type) centred around 10 200 cal. BP, 7800 cal. BP, 4800 cal. BP, 3100 cal. BP and 1700 cal. BP. Regional comparisons suggest a correlation of arid phases across southern Iberia and northwest Africa, which can be related to abrupt North Atlantic coolings (Bond events). [ABSTRACT FROM AUTHOR]

This paper describes our recent extraction of ancient DNA (aDNA) from Holocene pollen and discusses the potential of the technique for elucidating timescales of evolutionary change. We show that plastid DNA is recoverable and usable from pollen grains of Scots pine Pinus sylvestris from 10 ka and 100 years ago. Comparison of the ancient sequences with modern sequences, obtained from an extant population, establish a first genetic link between modern and fossil samples of Scots pine, providing a genetic continuity through time. One common haplotype is present in each of the three periods investigated, suggesting that it persisted near the lake throughout the postglacial. The retrieval of aDNA from pollen has major implications for palaeoecology by allowing (i) investigation of population-level dynamics in time and space, and (ii) tracing ancestry of populations and developing phylogenetic trees that include extinct as well as extant taxa. The method should work over the last glacial oscillation, thus giving access to ancestry of populations over a crucial period of time for the understanding of the relationship between speciation and climate change. [ABSTRACT FROM AUTHOR]

The Western Liaohe River Basin in northeastern China is one of the cradles of ancient Chinese civilization. Archaeological records from this region indicate that human occupation began about 8000 years ago and that agriculture and pastoralism were important activities from an early stage. Very little is known, however, about the effects that these activities had upon the landscape. This paper presents the results of a palaeoecological study from a 3.6 m sedimentary sequence in a relict oxbow lake in the Western Liaohe River Basin of southeast Inner Mongolia. The 5400-yr sequence indicates that human activities had a noticeable impact on an apparently open landscape. Buckwheat cultivation began as early as 5400 cal. yr BP with intensification of agricultural activities from approximately 4700 cal. yr BP. Nitrophilous plants such as Solanum and Cerastium, and also Artemisia were growing in the region at certain times, linked with fluctuations in the δ15N record and probably indicative of increased pastoralism and unintentional/intentional manuring. Burning was probably used for clearance of the steppe vegetation for agriculture with a close relationship apparent between increased influx of microfossil charcoal and the presence of buckwheat. Superimposed upon this record of human impact is also clear indication of three significant intervals of climate change between 2900 and 2600, 1200 and 600 and 600 and 30 cal. yr BP. The latter two are discussed in relation to the 'Mediaeval Warm Period' and 'Little Ice Age' apparent in sedimentary sequences across the Northern Hemisphere. Discussions are therefore made in terms of the impact that both climate change and ancient Chinese civilizations had upon shaping the present day landscape and vegetation. [ABSTRACT FROM AUTHOR]

Interactions between Holocene environmental changes and human subsistence strategies in semi-arid parts of eastern Africa are relatively poorly understood because of a paucity of sites where contemporaneous archaeological and palaeoenvironmental records are preserved. This paper presents new AMS 14C-dated palaeoenvironmental evidence of mid- to late-Holocene vegetation changes, in the form of pollen, charcoal, mineralogical and δ13Cbulk data, from a floodplain location on the Laikipia Plateau, Kenya, and in the context of information on modern plant–environment relationships, existing and new archaeological and historical data, and published palaeoclimatic records. Although relatively poorly resolved, the evidence indicates more wooded and relatively humid conditions compared with the present from before c. 6600 BP to c. 1900 BP. Evidence for vegetation changes over the last two millennia is more finely resolved and indicates increased burning and the expansion of fire-modified Acacia bushland c. 1900 BP and grassland c. 1700 BP. Burning to improve and extend pasture, and possibly to eradicate disease-prone habitats, may have been facilitated by prolonged periods of moisture deficits that might also have facilitated the spread of food production technologies. Vegetation changes c. 700 BP are associated with evidence for the occurrence of fires locally and could represent the activities of people and their animals close to the study site. [ABSTRACT FROM AUTHOR]

This paper examines the importance of palynological site selection criteria, specifically basin size, for the detection of vegetation mosaics and small- or local-scale human activity within a spatially diverse, mosaic landscape. Using a site selection strategy which recognizes landscape patchiness, pollen analyses from three small peat basins (10-56 m diameter) in an open, exposed upland valley (>250 m OD) provide records which are sensitive to local vegetation mosaics and small-scale, localized agriculture. The results indicate c. 4000 [sup 14]C years (4400 cal. years) of land use, with spatial and temporal variations in the valley. Contrasts between the sequences suggest that local pollen production remains an important component of the pollen rain deposited in small peat basins, even in open environments; this is especially true of palynological 'agricultural indicators'. By comparison, sites with regional pollen source areas underestimate the spatial diversity of the upland landscape, and are insensitive to small-scale human activity in an environment where the fragmentary distribution of soils suitable for agriculture favoured a small-scale, dispersed pattern of farming. It is therefore essential to match the spatial resolution of pollen records with the grain size or scale of variations in the environment under investigation in order to sense the scale of mosaics in vegetation and agriculture within patchy landscapes. [ABSTRACT FROM AUTHOR]

This paper examines the mid- to late-Holocene (c. 6850-1160 cal. yr BP) environmental history of Sierra de Gádor in southern Spain. The local vegetation dynamics are reconstructed through the palaeoecological record obtained from a lacustrine deposit situated at 1530 m. Various hypotheses are considered to explain the vegetation dynamics apparent in the palaeoecological evidence, including climatic change, fire occurrence and human activity. Although the vegetation in this region is sensitive to climatic change, threshold events driven by ecological factors are also apparent. Climatic events include a thermo-mesophytic optimum with abundance of deciduous trees and maximum lake water level found from c. 6850 to 5500 cal. yr BP. In contrast, changes in the frequency of major fire episodes appear to have shaped interspecific relationships and vegetation change, especially from c. 4200 cal. yr BP onwards. Biotic properties of the ecosystem such as the inertia of established tree populations, interconnected with competition adjustments, appear also to have played a role. Over the last two millennia, overgrazing, combined with natural and/or human-set fires, appears to have pushed mountain forests over a threshold leading to the spread of grassland, thorny scrub, junipers and nitrophilous communities. [ABSTRACT FROM AUTHOR]