This study presents a high-resolution palaeoclimate record from sediment cores collected from the siltation area of Laguna Comercocha (LC) in southern Peru, spanning the last 1070 cal years. The primary objective was to investigate climatic variations and environmental changes before, during and after the Little Ice Age (LIA) in the central Andes, with particular emphasis on precipitation patterns and their relation to solar forcing. The extracted core provided a continuous sedimentary archive, offering insights into climate variability on subcentennial to inter-decadal timescales. The methodology included analysing the sediment cores using X-ray fluorescence (XRF) to measure the concentrations of allogenic elements such as titanium (Ti), silicon (Si), potassium (K), iron (Fe) and calcium (Ca). Ti/coh ratios served as proxy for effective rainfall and runoff from the local catchment. In addition, pollen and non-pollen palynomorphs (NPPs) were identified and quantified to reconstruct past vegetation and climatic conditions. The study revealed that lithogenic input to the LC increased significantly after 1150 cal yr AD, likely due to increased precipitation. In particular, periods of increased lithogenic input were identified during the LIA, corresponding to solar minima and pointing to solar forcing as a major driver of precipitation changes in the central Andes.

This study examines the Roman burgus and medieval lowland castle ‘Zullestein’ near Biblis (Bergstraße district/Hessen/Germany) and its surrounding fluvio-scape. The aim of the study is to reassess the appearance of the fortifications and the surrounding area at the confluence of the River Weschnitz and the River Rhine based on the excavation results from the 1970s and current geoarchaeological research on site. Our approach encompasses electrical resistivity tomography, direct push sensing, sediment coring and the use of a high-resolution digital elevation model in combination with historical depictions of the Zullestein site from the 17th century AD. The findings of this integrative approach indicate that the Roman fort was likely located at a secondary channel of the River Rhine. With the renewed occupation of the Zullestein site by Lorsch Abbey during Carolingian times and the expansion into a lowland castle in the 11th century, the site was now located at the Weschnitz mouth into the Rhine, likely as part of anthropogenic interventions related to the Weschnitz fluvioscape. Traces of the final phase of the castle at the time of the Thirty Years’ War can still be seen in the terrain today and their attribution to individual elements of the historical account can be confirmed by the geoarchaeological results. The combination of methods presented in this study is a suitable option if excavations are not possible.

This integrated pedo-geoarchaeological study focuses on three abandoned pre-Hispanic terrace agricultural systems near Laramate in the southern Andes of Peru (14.5 degrees S), aiming to unravel the pedological and land-use history of the region, which served as a significant agricultural hub during pre-Hispanic times. The key objectives of the investigation involved contextualizing the former agricultural management system within its geomorphological and palaeoecological framework and assessing the impact of agricultural practices on soil development and quality by comparing non-irrigated agricultural terrace soils with their undisturbed palaeo-pedological counterparts. The Laramate terrace complex, with its diverse terrace systems and varied geomorphological and geological settings, provided an ideal setting for the investigation. This comprehensive examination integrated a range of methodologies, including field surveys, digital mapping, and geomorphological analysis based on GIS and remote sensing applications, soil analysis (e.g. grain size, bulk chemistry, nutrient budget), plant microfossils (phytoliths and starch), and radiocarbon dating.In the Laramate region, the geomorphological setting of terrace agricultural systems promotes their optimal functioning. The terraces are often located in sun-sheltered areas with western exposure on middle and lower slopes or valley bottoms, which mitigate intense solar radiation, reduce evapotranspiration, increase soil moisture, and minimize erosion. The study identifies three soil groups in the Laramate region: Phaeozems, Andosols, and Anthrosols. Unique characteristics of Phaeozems challenge typical descriptions, influenced by factors such as climatic seasonality, vegetation, fauna, lithology, and aeolian inputs. The terrace soils in the Laramate region are classified as Terric Anthrosols, showing no significant degradation even after long-term use. Their balanced acidity and nutrient levels support Andean crop cultivation. Traditional non-mechanized tools, such as the chaquitaclla and rucana, likely minimized soil disruption. The terrace tillage horizons have high organic matter, indicating intentional organic manuring. Phytolith concentrations suggest intensive agricultural activity, particularly maize cultivation, with varying patterns suggesting changes in cultivation, fertilization, or mulching practices over time. Starch grain identification aligns with phytolith analyses, reinforcing maize's significance in the region. Although the use of animal-origin fertilizers requires further investigation, there is no evidence of nutrient maintenance through seasonal burning. Irrigation was minimal, and the abandonment of the pre-Hispanic cultivation system was unlikely due to soil exhaustion or terrace instability.Overall, the pre-Hispanic history of terrace agriculture in the Laramate region extends over four development phases, reflecting dynamic interactions between environmental, cultural, and agricultural factors. The initial phase, from the Formative Paracas period to the Early Nasca period (800 BCE-200 CE), witnessed the establishment of agricultural terraces with simple terrace architecture, while the Middle Horizon (600-1000 CE) saw systematic areal expansion influenced by the Wari culture. Adaptations to drier conditions included terrace agriculture on volcanic soils. The Late Intermediate period (1000-1450 CE) witnessed hydrological variability and further terrace expansion to lower altitudes and less agriculturally suitable locations. The final phase, marked by the onset of the Hispanic colonial period in 1535 CE, saw the gradual abandonment of terrace agricultural systems due to demographic shifts and reorganization of production systems. Despite this, the historical trajectory underscores the adaptability and resilience of pre-Hispanic communities in the Laramate region, showcasing innovative terrace agriculture as a means of coping with changing environmental conditions across diverse landscape units.

Intensive human intervention in the natural drainage system of the Hessische Ried (Upper Rhine Graben, Germany) resulted in the transformation of a large wetland into an intensively used cultural landscape. At least since the first century CE, when Romans conducted early river regulation and water management, the natural water network has experienced extensive anthropogenic re-organisation. The LandGraben project focuses on the reconstruction of the natural and anthropogenic watercourse systems along the river Landgraben, a tributary to the river Rhine in the northern Hessische Ried. Several rivers from the southern Hessische Ried could have fed the river Landgraben during Roman times via the meandering Palaeo-Neckar depression, thus increasing both length and discharge of the Roman waterway.In this study, we present results of our investigations within the southern Hessische Ried to reconstruct the former channel network that was used by Romans for the transportation of troops, wares and border security. Our approach integrates the use of high-resolution digital elevation models (DEMs) as a base for geophysical measurements (electrical resistivity tomography, ERT), direct push sensing and sediment coring in combination with sedimentological and geochemical analyses of the encountered sedimentary units. Local chronostratigraphies were established based on radiocarbon dating.Based on our results, we are able to differentiate a palimpsest of several abandoned fluvial channels throughout the southern Hessische Ried and to reconstruct the spatio-temporal development of the corresponding fluvial systems. Chronostratigraphic data show that the Palaeo-Neckar stopped flowing through the Hessische Ried around 10 000 cal BCE. Moreover, we found that the river Weschnitz, the largest of the possible Landgraben tributaries, stopped flowing through the Palaeo-Neckar depression at ca. 3000 cal BCE. Instead, it took a right-angled shortcut westwards to the river Rhine, north of the city of Lorsch. For the first time, we present geomorphological evidence that the river Weschnitz was not diverted by the Romans as speculated so far. This is corroborated by numerous wooden posts of human-made construction crossing an E-W running water course at the modern Weschnitz knee, with the oldest posts being dendrochronologically dated to the fourth and third millennia BCE. We further argue that the river Winkelbach/Lauter formed its knee towards the river Rhine and thus left the Palaeo-Neckar depression not later than the second century CE but most probably even contemporaneously with the formation of the Weschnitz diversion. In the case of the Winkelbach/Lauter, a high-energy flood event presumably related to strong rainfall and/or meltwater processes in the Odenwald Mountains is assumed to be responsible for the initiation of the new, diverted water course. With regard to the Landgraben and its use as a waterway within the Roman fluvioscape of the Hessische Ried, we therefore conclude that the Romans successfully collected water from several smaller rivers, such as from the rivers Modau and Darmbach and from even smaller tributaries, to make the river Landgraben a navigable waterway. The rivers Weschnitz and Winkelbach/Lauter, however, did not contribute any water to the Landgraben system during Roman times. Umfangreiche menschliche Eingriffe in das natü rliche Entwä sserungssystem des Hessischen Rieds (Oberrheingraben, Deutschland) fü hrten zur Umwandlung eines weiträ umigen Feuchtgebiets in eine intensiv genutzte Kulturlandschaft. Spä testens seit dem 1. Jahrhundert n. Chr., als die Rö mer Regulierungsma ss nahmen an Flü ssen ergriffen, wurde das natü rliche Gewä ssernetz tiefgrü ndig umgestaltet. Das LandGraben-Projekt befasst sich mit der Rekonstruktion der natü rlichen und anthropogenen Gewä sserstrukturen entlang des Landgrabens, einem Nebenfluss des Rheins im nö rdlichen Hessischen Ried. Mehrere Flü sse aus dem sü dlichen Hessischen Ried kö nnten den Landgraben wä hrend der Rö merzeit ü ber die Altneckarniederung gespeist haben und damit sowohl die Lä nge als auch den Abfluss der rö mischen Wasserstra ss e vergröss ert haben.Diese Studie stellt die Rekonstruktion des ehemaligen Flussnetzes vor, das von den Rö mern fü r den Transport von Truppen, Waren und zur Grenzsicherung genutzt wurde. Unser Ansatz kombiniert hochauflö sende digitale Gelä ndemodelle, geophysikalische Messungen (Geoelektrische Widerstandstomographie), Direct Push Sensing und Sedimentkernbohrungen in Verbindung mit sedimentologischen und geochemischen Analysen der vorliegenden Sedimenteinheiten. Lokale Chronostratigraphien wurden auf der Grundlage von Radiokohlenstoffdatierungen erstellt.Basierend auf unseren Ergebnissen konnte zwischen verschiedenen verlandeten Flussrinnen im sü dlichen Hessischen Ried differenziert und die raum-zeitliche Entwicklung der entsprechenden fluvialen Systeme rekonstruiert werden. Chronostratigraphische Daten zeigen, dass der Altneckar um ca. 10 000 v. Chr. aufhö rte, durch das Hessische Ried zu entwä ssern. Bereits um ca. 3000 v. Chr. verlie ss die Weschnitz, der gröss te der mö glichen Landgrabenzuflü sse, die Altneckar-Niederung. Stattdessen nahm sie nö rdlich von Lorsch eine rechtwinklige Abkü rzung westwä rts zum Rhein. Damit ist erstmals geomorphologisch nachgewiesen, dass die Weschnitz nicht, wie bisher vermutet, von den Rö mern umgeleitet wurde. Diese Annahme wird durch das Vorhandensein zahlreicher Holzpfä hle unterstü tzt, die der Ü berquerung eines in Ost-West Richtung verlaufenden Flie ss gewä ssers am heutigen Weschnitzknie dienten. Fü r die ä ltesten dieser Pfä hle liegen dendrochronologische Datierungen in das 4. und 3. Jahrtausend v. Chr. vor. Weiterhin konnte festgestellt werden, dass der Winkelbach bzw. die Lauter die Altneckar-Niederung jedenfalls vor dem 2. Jh. n. Chr. in Richtung Rhein verlassen hat und sein Knie bildete. Hö chstwahrscheinlich geschah dies wesentlich frü her, nä mlich gleichzeitig mit der Entstehung des Weschnitzknies. Im Falle der Laufä nderung von Winkelbach bzw. Lauter wird ein hochenergetisches Ü berflutungsereignis, vermutlich im Zusammenhang mit starken Niederschlä gen und/oder Schmelzwasserprozessen im Odenwald verantwortlich gemacht. Im Hinblick auf den Landgraben und seine Nutzung als Wasserstra ss e in der rö mischen Flusslandschaft des Hessischen Rieds lä sst sich festhalten, dass die Rö mer das Wasser mehrerer kleinerer Flü sse, unter anderem der Modau, des Darmbachs sowie weiterer kleinerer Nebenflü sse, sammelten, um den Landgraben schiffbar zu machen. Die Flü sse Weschnitz und Winkelbach bzw. Lauter hingegen fü hrten dem Landgrabensystem in rö mischer Zeit kein Wasser zu.

Due to a general scarcity of archives and a lack of temporally highly resolved records, the response of Central European ecosystems to abrupt climate change during the Late Pleistocene - and notably the Last Glacial - has remained insufficiently explored. To contribute to a better understanding of the impact of short-term climate variability on ecosystems in Central Europe north of the Alps during that time, we present a new, near-continuous pollen record from Furamoos, southern Germany. Except for a hiatus from 28 to 20 ka BP, the record spans the past 130 kyrs in centennial-scale resolution. Our pollen dataset is augmented by sedimentological (i.e., XRF core scanning, loss on ignition, and maceral analysis) and macrobotanical data. This new record represents the yet most complete, temporally highest resolved reconstruction of terrestrial ecosystem dynamics in Central Europe for the Last Glacial period. Our results show that temperate forests thrived at Furamoos during full interglacial conditions (i.e., MIS 5e and MIS 1), boreal forests developed during the early glaciation (MIS 5 d-5a), and a tundra vegetation prevailed during full glacial conditions (MIS 4-2). Fourteen transient expansions (contractions) of tree and shrub populations that are synchronous with increases (decreases) in weathering intensity can be firmly attributed to specific Greenland Interstadials (Greenland Stadials) of the NGRIP ice-core record. By comparing individual expansions/contractions of tree and shrub populations with Greenland delta O-18(ice) ice-core and North Atlantic sea-surface temperature (SST) data, we show that during interstadials vegetation dynamics in Central Europe were closely linked to SSTs in the North Atlantic and decoupled from the climate recorded in Greenland; during stadials, the opposite pattern prevailed. We attribute these patterns to changes in AMOC strength and associated latitudinal shifts of the polar front. (C) 2022 Elsevier Ltd. All rights reserved.

The oribatid mites of a high-Andean cushion peatland in southern Peru were investigated. A total of 17 oribatid mite species, belonging to eight families, could be identified in five different microhabitats. A rarefaction analysis showed a potential mite community of maximum 18 taxa per 1000 specimens for this peatland site. Ranked species abundance analysis revealed three dominant, five subdominant, three recedent, two subrecedent and four sporadic occurring taxa. The abundance of oribatid mites was 3.0 specimens cm-3(SD = 5.9) in mean. However, significantly higher oribatid mite densities were detected in muddy soils and scarcely vegetated parts in comparison to soils covered by dense vegetation cushions. The identification of deposited and damaged remains of oribatid mites is discussed.

Despite a multitude of lead-contamination archives, the history of anthropogenic lead (Pb) contamination in Central Europe during the Holocene has remained incompletely understood. Contributing to a regionally differentiated understanding of Pb contamination in Central Europe since the Late Glacial (14.5 kyrs ago), this paper presents a record of atmospheric Pb deposition from an ombrotrophic peat bog at Furamoos, southern Germany. We combine Pb content and isotope data with pollen data allowing the interpretation of Pb signals within a context of natural change and human activities. The data show that Pb accumulation rates during the Late Glacial and early Holocene (0.074 mg*m(-2)*yr(-1)) were considerably higher than those during the midHolocene (0.016 mg*m(-2)*yr(-1)). Anthropogenic Pb contamination commenced at 3600 years BP and originates primarily from the Western Mediterranean region until the demise of the Roman Empire, after which contamination sources shifted to Britain, France, and Germany. For the past 3600 years, the data document an exponential increase in Pb contamination (max 5.6 mg*m(-2)*yr(-1)) that is unhinged from natural Pb deposition and far exceeds the natural Holocene background levels. The integrated geochemical and palynological approach allows placement of Pb contamination signals into detailed historical context. Land-use changes at Furamoos are consistent with the timing of political, economic, and social developments of medieval societies that modulated the ability and demand for mining during the past millennia.

Oxygen isotope records of cushion‐plant peat cellulose from the southern central Andes capture evidence for significant environmental changes. We observe that the δ18Ocell peatland record from Cerro Tuzgle (24°S) is in high conformity with the respective Lagunillas peatland record (27°S). During the late Holocene, two significant fluctuations occurred and are interpreted as regional moisture signals with increased precipitation amounts indicated during multi‐centennial phases from 1,530 to 1,270 cal. yr BP and from 470 to 70 cal. yr BP. These fluctuations can be best explained by changes in the strength of the South American summer monsoon (SASM). This interpretation is further supported by consistency with northern Andean paleoclimate records (10–13°S) and very high correlation (R2 = 0.76) with the Southern Oscillation Index. The congruent precipitation signals suggest the persistent climatic control of the SASM‐strength in this latitudinal band during the last 1,800 years.

Due to their location at the southern margin of the Arid Diagonal, only a limited number of archives in the western Central Andes of Chile is capable for paleoclimate investigations. High-altitude cushion peatlands are potentially suitable to fill this gap despite their heterogenic stratigraphies representing past geomorphodynamics, especially for the Late Holocene. We investigated a 4 m sediment profile from the Lagunillas cushion peatland (LP, 27'12' S, 69 degrees 17 W), located in the dry Puna of the Western Central Andes. Directed by Electrical Resistivity Tomography (ERT) measurements, sediment cores were recovered at the deepest point of the investigated valley section. In total, 10 radiocarbon samples were used to build the age-depth model resulting in a sediment chronology spanning the last 1800 cal. yr BR Core stratigraphy and ERT data were applied to allow insights into the sedimentary environment. Geochemical (X-ray fluorescence) and sedimentological (grain size) analyses were conducted to identify significant changes in sedimentation dynamics during the Late Holocene. Grain size analyses were investigated on 24 samples from peat layers as well as from stratigraphical sections characterized by allochthonous sediments. In combination with the results of the XRF measurements, evidence for changes in geomorphodynamic processes during the last 1800 cal. yr BP could be revealed. Our data disclose that investigations of heterogenic peat stratigraphies could also provide promising inferences about paleoclimatic changes. Within the Lagunillas record, stable phases of peat accumulation alternate with phases dominated by clastic material input. A stable phase of peat accumulation prevailed from 1750 cal. yr BP until about 1250 cal. yr BP and was followed by a phase with unstable conditions from 1250 to 980 cal. yr BP. During the Medieval Climate Anomaly (MCA) between 980 to 620 cal. yr BP, drier conditions prevailed at Lagunillas peatland, while shorter humid periods favored peat accumulation between 620 to 560 cal. yr BR Higher precipitation amounts were evident during the Little Ice Age (LIA) from 560-160 cal. yr BR During the period from 160 cal. yr BP to recent times, a higher frequency of changes between peat accumulation and clastic layers occurred, presumably due to a decreasing trend in precipitation.

X-ray fluorescence core scanning (XRF-CS) has become a standard tool in paleoenvironmental studies. Allowing rapid, inexpensive and non-destructive analysis of the elemental composition of sediment cores at high spatial resolution, it is ideally suited for the reconstruction of short-term climatic change. However, its applicability to cores consisting of peat and other highly organic-rich sediments has yet remained poorly explored. We have therefore investigated the application of XRF-CS to two cores consisting of ombrotrophic peat and of fen peat and organic-rich muds of Late Glacial-Holocene and Eemian age, respectively, from a peat bog in Southern Germany using an Avaatech 4th-generation XRF core scanner. The XRF-CS-derived distributions of elements widely used in (paleo)environmental research (i.e., Al, Ca, Fe, K, Mg, Mn, S, Si, and Ti) were systematically compared to the results of inductively coupled plasma optical emission spectrometry analyses. For the Late Glacial-Holocene peat core, XRF-CS yielded reliable semiquantitative data for the majority of the investigated elements (i.e., Ca, Fe, K, Mn, S, Si, and Ti), with R2 ≥ 0.5. XRF-CS of the Eemian fen peat and organic-rich muds yielded reliable data for Al, K, S, and Ti (R2 ≥ 0.5) and, to a lesser extent, for Fe (R2 = 0.46). and Si (R2 = 0.25). This indicates that XRF-CS allows to semiquantitatively reconstruct the distribution of the majority of paleoclimatically relevant elements in peat and other highly organic-rich sediments. Hence, XRF-CS is well suited to complement the analytical toolbox for the paleoenvironmental study of such sediments.

The disastrous volcanic eruption of Thera in the Aegean that happened in late seventeenth century BC (Late Bronce Age, LBA) buried under a thick mantle of volcanic ash the thriving city harbor of Akrotiri, situated at the southern edge of the island. The archaeological excavations at the site have witnessed the city's wealth and flourish; numerous, luxurious, and outlandish finds clearly indicate well-established maritime contacts between Akrotiri and eastern Mediterranean lands. Such maritime operations and overseas trade required, apparently, adequate harbor facilities. This paper deals with geoarchaeological and geophysical studies aiming at the localization of the buried harbor, a so far unrealized ambitious aim, in spite of the repeated intense attempts undertaken in the last decades. Preference for the relevant investigation was given to three small littoral valleys situated in small distances at both sides of the settlement, suggesting shallow bays before the Minoan eruption, hence probably having hosted the searched harbor(s). Prior to the fieldwork undertaken, all available geological and other related data were cartographically outlaid by means of GIS. Afterwards, in situ geomorphologic studies were conducted, followed by one littoral drilling and geophysical investigations including seismic refraction and electrical resistivity tomography (ERT). Both geophysics and drilling have shown that the hard pre-Minoan basement (consisting of dense andesitic lavas) is situated at depths of ca. 25 m in the Mavrorachidi valley. According to the seismic results, the recent shape of Potamos valley today seems to be similar to as during the Minoan times. Due to the relative minor infillings of the valley and the position of the valley floor above the recent sea level, there's no evidence of a former bay or harbor in that area. Moreover, the seismic data revealed that the Minoan surface (Cape Riva ignimbrite) seems to rise from the archaeological site of Akrotiri to the coastline in the southeast of the excavation up to 30 m a. s. l. Maybe there existed a former cliff that was covered by Minoan tephra but that also provided shelter for the village of Akrotiri. The investigated area south of the archaeological site offers a more appropriate site for the Minoan harbor. Future geoarchaeological investigations (drillings, geophysics) should concentrate both on the latter area and on Mavrorachidi valley (one of the three valleys mentioned before). This study presents preliminary results from our ongoing research. It is anticipated that the synthesis of the available data along with the expected results from the remainder geophysical investigation, subsurface coring, chronometric dating, and submarine beach-rock studies will allow to determine the most probable harbor position(s) of Akrotiri.

Several archaeological studies in the Central Andes have pointed at the temporal coincidence of climatic fluctuations (both long- and short-term) and episodes of cultural transition and changes of socioeconomic structures throughout the pre-Columbian period. Although most scholars explain the connection between environmental and cultural changes by the impact of climatic alterations on the capacities of the ecosystems inhabited by pre-Columbian cultures, direct evidence for assumed demographic consequences is missing so far. In this study, we address directly the impact of climatic changes on the spatial population dynamics of the Central Andes. We use a large dataset of pre-Columbian mitochondrial DNA sequences from the northern Rio Grande de Nasca drainage (RGND) in southern Peru, dating from ∼840 BC to 1450 AD. Alternative demographic scenarios are tested using Bayesian serial coalescent simulations in an approximate Bayesian computational framework. Our results indicate migrations from the lower coastal valleys of southern Peru into the Andean highlands coincident with increasing climate variability at the end of the Nasca culture at ∼640 AD. We also find support for a back-migration from the highlands to the coast coincident with droughts in the southeastern Andean highlands and improvement of climatic conditions on the coast after the decline of the Wari and Tiwanaku empires (∼1200 AD), leading to a genetic homogenization in the RGND and probably southern Peru as a whole.

The southern Peruvian coastal desert around Palpa, southern Peru (14.5°S) is currently characterized by hyper-arid conditions. However, the presence of two species of molluscs (Scutalus, Pupoides) and desert-loess deposits indicates the past development of semi-desert and grassland ecosystems caused by a displacement of the eastern desert margin due to hydrological changes. Radiocarbon dating shows that the transition to a semi-arid climate in the southern Peruvian coastal desert took place during the Greenland interstadial 1, ∼ 13.5 cal ka BP. At the beginning of the Holocene, the mollusc fauna vanished due to increasing humidity and the development of grasslands. Dust particles were fixed by the grasses, as indicated by abundant Poaceae phytoliths, and desert loess was formed. The humid period we observe here is out of phase with the palaeoenvironmental records from the Titicaca region, which indicates dry conditions at that time. This paper offers a new idea for this contradiction: an orbitally driven meridional shift of the Bolivian high might have altered the moisture supply across the Andes.

For the first time in South America, we found specific constructions for water harvesting from the Late Intermediate period. Their configuration allows the precise reconstruction of mean annual precipitation during that time. In that area, enhanced precipitation enabled the people to cultivate the desert. The remains of human occupation give evidence of a short climatic oscillation in the northern Atacama desert around similar to 1300 AD.

Geoarchaeological evidence for Holocene palaeoclimates in the eastern Atacama desert is compiled to reconstruct the palaeoenvironmental history in the Andean foreland. In contrast to earlier assumptions that El Nino events controlled the environment of pre-Columbian people in the Ica-Nazca region, major hydrological changes, triggered by oscillations of the summer monsoon in the western Andes, concurred with cultural changes.Loess deposits, phytoliths, and snail shells indicate that during the early and middle Holocene the eastern Atacama desert was a grassland until the third millennium BC. With the aridisation hunter-gatherer people concentrated on favourable sites along the river oases, which were flooded seasonally by reliable rains in the western Andes. During the rise of the Paracas culture the increasing population density went hand in hand with the formation of more complex societies. After similar to 200 BC the Nasca displaced the Paracas culture. Approximately four centuries later the aridisation of the region accelerated and the Nasca settlements shifted eastwards into the valleys of the Andean footzone. With even more reduced summer rains in the western Andes, the river oases dried up. Finally, shortly after 600 AD, the Nasca culture collapsed.A new hydrological oscillation took place after similar to 1100 AD. Monsoonal rains reached the Andean foreland again and narrowed the desert to similar to 40 km. During the following Late Intermediate Period (LIP), pre-Columbian people re-occupied the eastern Atacama desert until the sixteenth century AD. The Little Ice Age, with its coldest temperatures between the seventeenth and nineteenth centuries AD, was a very dry period in the study area, so that LIP settlements were abandoned and desert conditions reappeared lasting until today.