A Paleo-Lake and wetland paleoecology associated with human use of the distal Old River Bed Delta at the Pleistocene-Holocene transition in the Bonneville Basin, Utah, USA

Investigating Environmental (Climate and Vegetation) Change of Eastern Amazonia During Pleistocene and Holocene Using Multi-Proxy Analysis

Late Pleistocene and early Holocene climate and limnological changes in the Sierra Nevada, California, USA inferred from midges (Insecta: Diptera: Chironomidae)

Late Quaternary glaciation of México

High-resolution analysis of pollen from Poza Cortador, Cuatrociénegas, Mexico was conducted for the period 13,600–11,300 cal yr BP. Results indicate that rapid cooling, coincident with the Younger Dryas chronozone, led to rapid shifts in the vegetation of the Chihuahuan Desert. Prior to the Younger Dryas, desert taxa like Acacia were increasing in abundance. This expansion was suppressed by apparent cooling and shifts in regional hydrology. The interval associated with the Younger Dryas has two phases. An initial phase from 13,010 to 12,455 cal yr BP had an expansion of mixed conifer woodlands with co-mingled pine, juniper, and oaks. From 12,455 to 11,915 cal yr BP, juniper became dominant in these woodlands. Wetland dynamics show concomitant hydrologic changes impacting the region. Seagrass ( Ruppia ) pollen spiked near 13,010 cal yr BP, suggesting a shift from fresh- to brackish marsh condition early in the Younger Dryas chronozone. A subsequent freshening of the marshes is suggested with increases in sedges for most of this initial period. The second phase of the Younger Dryas, when Juniper became began to dominate woodland composition at 12,455 cal yr BP, coincides with a loss of macrophytes and dominance of the marsh by salt-tolerant grasses, asters and forbs. Detailed analysis of pollen through this period of rapid climate change provides insights into the natural rate of change in aridland ecosystems and the resiliency of these systems to both temperature and hydrologic change.

Holocene paleoecology and paleoceanography of the southwestern Black Sea shelf revealed by ostracod assemblages

Response of prehistoric human activity to environmental changes since 7,000 cal yr BP in Nenjiang River Basin, northeast China

Lateglacial and early-Holocene climate variability reconstructed from multi-proxy records on Andøya, northern Norway

Relict permafrost preserves megafauna, insects, pollen, soils and pore-ice isotopes of the mammoth steppe and its collapse in central Yukon

Aquatic ecosystem responses to environmental and climatic changes in NE China since the last deglaciation (∼17, 500 cal yr BP) tracked by diatom assemblages from Lake Moon

Long-term vegetation dynamics along altitudinal and longitudinal gradients in the Hyrcanian forest region (northern Iran)

Late-Glacial and Holocene forest dynamics at Steregoiu in the Gutaiului Mountains, Northwest Romania

In order to study the stability and dynamics of highly biodiverse mountain rain forest and paramo ecosystems, the late Pleistocene and Holocene climate and fire variability as well as human impact in the Podocarpus National Park region, the first comprehensive palaeoenviremental study from the southeastern Ecuadorian Andes will be presented. An initial study of recent vegetation/modern pollen rain relationship on an altitudinal transects between 1800 and 3200 m elevation in the mountain forest and (sub)-paramo vegetation of the ECSF (Estacion Cientifica San Francisco) research area provide important background information in the interpretation of late Quaternary pollen records. Cluster analysis on the pollen rain data by CONISS, clearly reflects the zonation of the different vegetation units, lower mountain forest (LMF), upper mountain forest (UMF) and (sub)-paramo. A relatively high number of pollen taxa correspond to the altitudinal distribution of genera and families of modern vegetation. The modern tree line in the research area is at ca. 2790 m, which is pointed out by an increase of (sub)-paramo taxa and a decrease of mountain forest taxa in the pollen rain data. Palaeoenvironmental changes, inferred from 9 lake, peat bog and soil deposits, collected at different elevations between ca. 2000 and 3300 m, were investigated by pollen, spores and charcoal analysis, in combination with XRF- and magnetic susceptibility-scanning on the lake sediment cores. During the late Pleistocene from ca. 21,000 to 11,200 cal yr BP, grass-paramo vegetation occurred at the Tiro-Pass (2810 m), reflecting cold and moist climatic conditions as well as a shift of vegetation zones into lower elevation during this period. During the transition from late Pleistocene to early Holocene from ca. 14,500 to 9700 cal yr BP, arboreal taxa, mainly Weinmannia strongly increase at Laguna Cocha Caranga (2710 m), reflecting a raise in temperature. The early Holocene from ca. 11,200 to 8900 cal yr BP (El Tiro-Pass) is characterised by an increase of temperature and moisture, as well as a shift of vegetation zones into higher elevation. During the mid Holocene period, from ca. 8900 to 3300 cal yr BP, upper mountain forest vegetation developed at the El Tiro-Pass, where subparamo vegetation occurred in recent times, suggesting a warmer climate than present day at this elevation. XRF-scanning data from Laguna Rabadilla de Vaca (3310 m) reflects a drier period from ca. 8990 to 6380 cal yr BP and a wetter period from ca. 6380 to 3680 cal yr BP. The green algae Botryococcus braunii, Isoetes and Cyperaceae were used to reconstruct Holocene wet/dry phases at Laguna Cocha Caranga. Drier climatic conditions occurred from ca. 9700 to 6900 cal yr BP and from ca. 4200 to 1300 cal yr BP. From ca. 6900 to 4200 cal yr BP and from ca. 1300 cal yr BP to modern time"s wetter climatic conditions occurred. During the late Holocene, modern climatic conditions, as well as recent vegetation established since ca. 3680 cal yr BP at Laguna Rabadilla de Vaca and since ca. 3300 cal yr BP at the El Tiro-Pass. An increase of fire intensity during the early to mid Holocene period after ca. 9700 cal yr BP at Laguna Cocha Caranga and after about 7500 cal yr BP at the El Tiro-Pass reflects beginning human impact on the ecosystem in the Podocarpus National Park region. High occurrence of grasses document, that past fires have markedly influenced the floristic composition of the mountain rain forest and paramo ecosystems during the mid to late Holocene period. The reduction of fire intensity coupled with a decrease of grasses after ca. 1300 cal yr BP (Laguna Cocha Caranga) and between ca. 970 to 400 cal yr BP (Upper Rio San Francisco valley), coupled with a missing of Zea mais pollen, suggests a reduction and/or absence of human activities, may be as a result of political unrest. After the reduction and/or absence of human influence the mountain forest vegetation starts to recover.

Late Quaternary environmental changes in Marguerite Bay, Antarctic Peninsula, inferred from lake sediments and raised beaches

Reconstruction of climatic and environmental changes in NW Romania during the early part of the last deglaciation (∼15,000–13,600 cal yr BP)

Palaeoenvironmental changes since Pleistocene–Holocene transition: Pollen analysis from a wetland in southwestern Patagonia (Argentina)