The expansion of Araucaria forest in the southern Brazilian highlands during the last 4000 years and its implications for the development of the Taquara/Itararé Tradition

Reproduced with permission of the publisher. Copyright © Maney Publishing 2007.An examination of the late Holocene environmental and cultural sequences of the southern Brazilian highlands indicates that the colonisation of this region by the Taquara/Itararé people is associated with the expansion of Araucaria forest resulting from the onset of wetter climatic conditions in the region, which started between around 1410 and 900 cal. yr BP. The more intense and permanent human occupation of this region is associated with the advance of Araucaria forest, which provided Taquara/Itararé groups with a newly abundant and reliable resource: Araucaria seeds. In addition, we review the evidence for landscape transformation associated with the beginning of food-production in the region. Charcoal records show that local populations may have practiced slash-and-burn agriculture at lower elevations since the beginning of the late Holocene around 4320 cal. yr BP, and continued this practice during the second part of the late Holocene

Automated spatiotemporal landslide mapping over large areas using RapidEye time series data

In the past, different approaches for automated landslide identification based on multispectral satellite remote sensing were developed to focus on the analysis of the spatial distribution of landslide occurrences related to distinct triggering events. However, many regions, including southern Kyrgyzstan, experience ongoing process activity requiring continual multi-temporal analysis. For this purpose, an automated object-oriented landslide mapping approach has been developed based on RapidEye time series data complemented by relief information. The approach builds on analyzing temporal NDVI-trajectories for the separation between landslide-related surface changes and other land cover changes. To accommodate the variety of landslide phenomena occurring in the 7500 km2 study area, a combination of pixel-based multiple thresholds and object-oriented analysis has been implemented including the discrimination of uncertainty-related landslide likelihood classes. Applying the approach to the whole study area for the time period between 2009 and 2013 has resulted in the multi-temporal identification of 471 landslide objects. A quantitative accuracy assessment for two independent validation sites has revealed overall high mapping accuracy (Quality Percentage: 80%), proving the suitability of the developed approach for efficient spatiotemporal landslide mapping over large areas, representing an important prerequisite for objective landslide hazard and risk assessment at the regional scale

Long-term persistence of steppe vegetation in the highlands of Arasbaran protected area, northwestern Iran, as inferred from a pollen record

Palynological analysis and radiocarbon dating of a short sediment core from a high-altitude mire in the Arasbaran area of northwestern Iran reveals long-term vegetation dynamics, climate change and anthropogenic impact. Our findings indicate the prevalence of semi-desert steppe vegetation, with a variety of Asteraceae - mainly Lactuceae - species from 3000 to 1440 cal yr BP. This period is followed by a higher occurrence of Artemisia spp. and Brassicaceae (1440-1330 cal yr BP), a re-expansion of Lactuceae (1330-1030 cal yr BP) and Brassicaceae (1030-330 cal yr BP) and, finally, Caryophyllaceae species (since 330 cal yr BP). The reconstructed millennia-long dry climate in the highlands of northwestern Iran is in good accordance with climate reconstructions from other east Mediterranean sites. Two phases of moister conditions between 2100-1400 and 1000-350 cal yr BP would correspond to altitudinal Quercus-Carpinus forest expansion in the Arasbaran area. The earliest indication of anthropogenic activity in the area dates back to the onset of the record, around 3000 cal yr BP. The occurrence of small maxima of Juglans regia, Corylus avellana and Cornus mas pollen at around 1350 cal yr BP is interpreted to reflect a temporary expansion of fruit cultivation. For the last millennium the occurrence of pollen attributable to Polygonum, Euphorbia, Plantago and Rumex suggests a diversification of steppe vegetation, which may reflect intensified agropastoral activities in the Arasbaran highlands. Based on our pollen record, the regional vegetation in the Kalan area remained largely stable over the last three millennia. However, changes in local hydrology caused substantial changes in wetland vegetation

BRAZILIAN ARCHIVES OF BIOLOGY AND TECHNOLOGY A N I N T E R N A T I O N A L J O U R N A L Late Holocene Vegetation History and Early Evidence of Araucaria angustifolia in Caçapava do Sul in the Lowland Region of Rio Grande do Sul State, Southern Brazil

ABSTRACT Little is known about the southernmost occurrence of small areas with Araucaria angustifolia populations in Caçapava do Sul in low elevated areas of Rio Grande d

Intensification of agriculture in southwestern Germany between the Bronze Age and Medieval period, based on archaeobotanical data from Baden-Württemberg

A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern Germany since the Bronze Age. It involved fallow periods, where the arable land is left without crops in order to let it recover its fertility for several years while becoming grassland. This led to regeneration of the topsoil humus, which could later be mobilized by cultivation. With later farming systems, the supply of nutrients needed for crops could also be provided by manuring, which allowed shorter fallow periods but required the production of manure. Such cultivation systems with short or even without fallow phases and with intensive manuring are known from the medieval period as one, two or three field systems of agriculture and their development was an important step towards the intensification of farming. The current study considers on-site plant macrofossil data from archaeological sites as well as the off-site pollen data from cores in Baden-Württemberg in order to recognize the main changes towards agricultural intensification through time from the Bronze Age up to medieval times. The various landscape types included in the study area also reveal their different agricultural histories of intensification. In lowlands with good soils, the intensification can be recognized earlier and more strongly than in uplands or other marginal areas. The main shift towards intensification took place in the Roman period, which is also confirmed by written sources of the time that mention manuring as well as a kind of two field system and alternation between grassland and arable land.publishedVersio

Colombian dry moist forest transitions in the Llanos Orientales—Acomparison of model and pollen-based biome reconstructions

Colombian vegetation, at the ecological level of the biome, is reconstructed at six sites using pollen data assigned a priori to plant functional types and biomes. The chosen sites incorporate four savanna sites (Laguna Sardinas, Laguna Angel, El Pin˜al and Laguna Carimagua), a site on the transition between savanna and Amazon rainforest (Loma Linda) and a site within the Amazon rainforest (Pantano de Monica). The areal extent of tropical moist forest, tropical dry forest and steppe have been subject to significant change: differential responses of the vegetation to climatic shifts are related to changes in plant available moisture, duration of dry season and edaphic controls on the vegetation. The record from El Pin˜al shows that the present-day savanna vegetation, dominated by steppe (Poaceae) with little occurrence of woody savanna taxa (e.g. Curatella, Byrsonima), was present since the last glacial period of the northern hemisphere. Unfortunately, El Pin˜al is located on an edaphic savanna and is not particularly responsive to registering change. Most records cover the early Holocene; one site records the El Abra stadial (Younger Dryas equivalent), when forest expansion reflects more humid climatic conditions and higher plant available moisture. During the early and middle Holocene, the maximum expansion of steppe and tropical dry forest occurred, indicating that dry climatic conditions continued to around 4000 CBP. The following period, from shortly before 4000 C BP, is characterised by an increase in forest and gallery forests, reflecting a wetter period probably with a shorter annual dry season. Anthropogenic influence on the vegetation is recorded by all the records over the last millennial, particularly characterised by a reduction in forest cover and high amplitude changes in vegetation. Biome transitions from one type to another, and the environmental controls on this shift, are investigated by applying a vegetation model (BIOME-3). The model uses climatic data from six meteorological stations that, encompass a range of environments within lowland Colombia, which are similar to the pollen data. The signals of vegetation change can be translated to the main environmental controls of temperature and moisture to indicate the degree of change needed in these parameters to record the vegetation change depicted by the pollen data. Moisture balance is the dominant control on driving vegetation change whether under seasonal or annual control. The combined reconstruction from pollen data and model output of biome-scale vegetation dynamics for lowland Colombia allows an understanding of the environmental controls to be developed