Site Abandonment Research Articles

Cultural implications of late Holocene climate change in the Cuenca Oriental, Mexico

There is currently no consensus on the importance of climate change in Mesoamerican prehistory. Some invoke drought as a causal factor in major cultural transitions, including the abandonment of many sites at 900 CE, while others conclude that cultural factors were more important. This lack of agreement reflects the fact that the history of climate change in many regions of Mesoamerica is poorly understood. We present paleolimnological evidence suggesting that climate change was important in the abandonment of Cantona between 900 CE and 1050 CE. At its peak, Cantona was one of the largest cities in pre-Columbian Mesoamerica, with a population of 90,000 inhabitants. The site is located in the Cuenca Oriental, a semiarid basin east of Mexico City. We developed a subcentennial reconstruction of regional climate from a nearby maar lake, Aljojuca. The modern climatology of the region suggests that sediments record changes in summer monsoonal precipitation. Elemental geochemistry (X-ray fluorescence) and δ(18)O from authigenic calcite indicate a centennial-scale arid interval between 500 CE and 1150 CE, overlaid on a long-term drying trend. Comparison of this record to Cantona's chronology suggests that both the city's peak population and its abandonment occurred during this arid period. The human response to climate change most likely resulted from the interplay of environmental and political factors. During earlier periods of Cantona's history, increasing aridity and political unrest may have actually increased the city's importance. However, by 1050 CE, this extended arid period, possibly combined with regional political change, contributed to the city's abandonment.

Survival at the Frontier of Holy War: Political Expansion, Crusading, Environmental Exploitation and the Medieval Colonizing Settlement at Biała Góra, North Poland

Between the eleventh and thirteenth centuries AD, the Lower Vistula valley represented a permeable and shifting frontier between Pomerelia (eastern Pomerania), which had been incorporated into the Polish Christian state by the end of the tenth century, and the territories of western Prussian tribes, who had resisted attempts at Christianization. Pomeranian colonization eventually began to falter in the latter decades of the twelfth and early thirteenth centuries, most likely as a result of Prussian incursions, which saw the abandonment of sites across the borderland. Subsequently, the Teutonic Order and its allies led a protracted holy war against the Prussian tribes, which resulted in the conquest of the region and its incorporation into a theocratic state by the end of the thirteenth century. This was accompanied by a second wave of colonization, which resulted in the settlement pattern that is still visible in the landscape of north-central Poland today. However, not all colonies were destroyed or abandoned in between the two phases of colonization. The recently excavated site of Biała Góra, situated on the western side of the Forest of Sztum overlooking the River Nogat, represents a unique example of a transitional settlement that included both Pomeranian and Teutonic Order phases. The aim of this paper is to situate the site within its broader landscape context which can be characterized as a militarized frontier, where, from the later twelfth century and throughout much of the thirteenth century, political and economic expansion was combined with the ideology of Christian holy war and missionary activity. This paper considers how the colonists provisioned and sustained themselves in comparison to other sites within the region, and how Biała Góra may be tentatively linked to a documented but otherwise lost outpost in this volatile borderland.

Geoarchaeological observations in the wider area of Nemea using airphotos and GIS

The northeastern part of the Peloponnese is tectonically active and it is the object of study of many geomorphologists since it provides information for the evolution of the terrain, comparable with other similar areas. The study area in this paper is a small segment of northeastern Peloponnese, where we try to understand the evolution of the relief using geomorphological and archaeological data. We study the flow of the river systems Asopos and Nemeas - which are in the wider area of the Nemea archaeological site - in order to understand how the evolution of these rivers in time affected the overall image of the area. In order to access our goal, aerial photographs and GIS analysis were used. The geomorphological and tectonic analysis of the area and the development and evolution of settlements therein (based on archaeological studies) gave us clues regarding the shape of the terrain over time. The main factors affecting the shape of the terrain (intense tectonic activity and headward erosion) were not adequate reasons - in our case - to effect immediate abandonment of the area (since, in the human timescale, they are fairly slow processes). Their effect, however, is evident over time, in the form of gradual abandonment of sites, movement of settlements or the creation of new settlements.

A glacial cryptic refuge in south‐east Australia: human occupation and mobility from 36 000 years ago in the Sydney Basin, New South Wales

ABSTRACTExcavations across a source‐bordering dune overlooking the Hawkesbury River in north‐west Sydney, Australia, suggest initial occupation of the region by at least 36 ka, with variable but uninterrupted use until the early Holocene; following abandonment, the site was then re‐occupied by ∼3 ka. Along with a handful of other sites, the results provide the earliest reliable evidence of permanent regional populations within south‐eastern Australia, and support a model in which early colonizers followed the coastal fringe with forays along the main river systems. The evidence is consistent with the demographic model of Williams, 2013 (Proceedings of the Royal Society Series B 280: 20130486), which suggested low, but established regional populations before the Last Glacial Maximum (LGM), a population nadir following the LGM and increasing use of the region from ∼12 to 8 ka. The site exhibits increased use at the onset and peak of the LGM, and provides an example of a cryptic refuge as defined by Smith, 2013 (The Archaeology of Australia's Deserts. Cambridge University Press: New York). Specifically, changing artefact densities and attributes show the site was used repeatedly, but for shorter periods through this time, and suggest it formed one of a series of key localities in a point‐to‐point (rather than home‐base) subsistence strategy. This strategy was maintained until the site's abandonment in the early Holocene, despite changing population and climatic conditions through the Terminal Pleistocene.

A Geo-Historical Study of Site Formation at a Nineteenth-Century Farmstead in Lake County, Illinois

Agricultural journals were in wide circulation in the nineteenth century, and they were means of transmitting information about agrarian technologies and techniques to American Frontier-Phase farmers. This article explores the environmental and cultural context for the addition of a drainage feature to a nineteenth-century farmstead in Illinois (called the Bond Farm site), which preceded the site’s eventual abandonment when rainfall reached anomalously high levels. Geoarchaeological and paleoclimatologic datasets are presented as evidence of high rainfall, and the period of site settlement is constrained by both artifact and documentary sources. High maintenance costs associated with occupying the structure apparently exceeded the value of remaining, so the site was abandoned. As archaeologists grapple with how to determine causation in site occupation and abandonment, we advocate a multidisciplinary research design in historical archaeology that includes geoarchaeological analyses, which can be useful in building a microscale settlement reconstruction.

Evidence of climate-induced range contractions in bull trout Salvelinus confluentus in a Rocky Mountain watershed, U.S.A.

Many freshwater fish species are considered vulnerable to stream temperature warming associated with climate change because they are ectothermic, yet there are surprisingly few studies documenting changes in distributions. Streams and rivers in the U.S. Rocky Mountains have been warming for several decades. At the same time these systems have been experiencing an increase in the severity and frequency of wildfires, which often results in habitat changes including increased water temperatures. We resampled 74 sites across a Rocky Mountain watershed 17 to 20 years after initial samples to determine whether there were trends in bull trout occurrence associated with temperature, wildfire, or other habitat variables. We found that site abandonment probabilities (0.36) were significantly higher than colonization probabilities (0.13), which indicated a reduction in the number of occupied sites. Site abandonment probabilities were greater at low elevations with warm temperatures. Other covariates, such as the presence of wildfire, nonnative brook trout, proximity to areas with many adults, and various stream habitat descriptors, were not associated with changes in probability of occupancy. Higher abandonment probabilities at low elevation for bull trout provide initial evidence validating the predictions made by bioclimatic models that bull trout populations will retreat to higher, cooler thermal refuges as water temperatures increase. The geographic breadth of these declines across the region is unknown but the approach of revisiting historical sites using an occupancy framework provides a useful template for additional assessments.

A multi-objective supply chain optimisation using enhanced Bees Algorithm with adaptive neighbourhood search and site abandonment strategy

In this paper, an enhanced version of the Bees Algorithm is proposed in dealing with multi-objective supply chain model to find the optimum configuration of a given supply chain problem in order to minimise the total cost and the total lead-time. The new Bees Algorithm includes an adaptive neighbourhood size change and site abandonment (ANSSA) strategy which is an enhancement to the basic Bees Algorithm. The supply chain case study utilised in this work is taken from literature and several experiments have been conducted in order to show the performances, the strength, the weaknesses of the proposed method and the results have been compared to those achieved by the basic Bees Algorithm and Ant Colony optimisation. The results show that the proposed ANSSA-based Bees Algorithm is able to achieve better Pareto solutions for the supply chain problem.

Sites forlorn: dating intervals of abandonment at three shell middens on Santa Cruz Island, California using Bayesian chronological models

Archaeologists interested in variable mobility patterns and the factors that influence them rely on chronometric data to illuminate repetitive cycles of occupation, abandonment, and reoccupation. This article establishes and interrogates Bayesian chronological models in order to provide formal age estimates for two distinct intervals of site abandonment at three substantial multi-component shell middens from Santa Cruz Island, California. The earlier, more protracted interval of abandonment (ca. 2629–1698 cal. BP) following terminal Early Period occupation at each site location represents a temporal datum for a series of significant cultural, demographic, and technological developments throughout the region. I propose that this interval of localized site abandonments indicates a period of reorganization provoked by a shift in the paleoenvironment, a preliminary hypothesis that requires further testing. This research calls for development of similarly rigorous site chronologies on Santa Cruz Island and throughout the region that will shed further light on the validity of the temporal gaps documented in this analysis and most certainly will facilitate the development of additional hypotheses. More broadly, this article highlights the implementation and benefit of a Bayesian approach to building and interrogating site chronologies.

Soil nutrient stock dynamics and land-use management of annuals, perennials and pastures after slash-and-burn in the Southern Ecuadorian Andes

Quantification of nutrient stocks and their temporal changes are considered of prime importance in farming systems of the humid tropics to answer the question of sustainable management. The research area in the Southern Ecuadorian Andes included forest, annual (0–5 years old) and different aged perennial (0–5, 6–10, 11–20, 21–30) and pasture (0–5, 6–10, 11–20, 21–30, >30) sites. Soil organic carbon (SOC), total and plant available soil nutrient stocks and nutrient balances were investigated to assess temporal soil nutrient dynamics in relation to management activities. Forest conversion by slash-and-burn caused a decrease in SOC stocks in all three land-uses amounting between 14% and 19%. This was mainly due to the absence of an organic layer and losses in the upper five cm of the mineral soil. Stocks of exchangeable bases and pH values increased in annuals which however, had the most negative nutrient balance of all land-uses amounting to −128, −25 and −226kgha−1a−1 for N, P and K, respectively. The abandonment of annual sites after five years was linked to a shortage of available N and P due to low-external-input management which caused SOC stock decreases. Major soil nutrient changes in perennials and pastures did not occur directly but 6–20 years after forest conversion with increases in stocks for total N, P, S and exchangeable bases above forest level. SOC stocks of medium aged perennials and pastures increased above forest level in the mineral soil. Easily available inorganic N and P stocks remained low throughout the chronosequence in perennials and pastures, indicating a quick uptake by plant roots and microorganisms. Compared to medium aged sites, oldest perennials and pastures showed a strong decrease in SOC (−28% and −16%) and soil nutrient stocks. Stocks for total N, P, S and exchangeable bases were up to 50% below those of medium aged sites in oldest perennials and pastures.

The Social and Ecological Trajectory of Prehistoric Cambodian Earthworks

This article moves discussion of prehistoric earthworks in Cambodia from normative archaeology into an ecological landscape structure, based on archaeological data sets. Discussions provide a synthesis of archaeological and newly borne-out ecological explanations for original site construction, occupation, landscape use, sustainability of occupation for the earthwork culture over a 2000-year period and terminal use of the sites. A model is presented to assess site abandonment and post-earthwork region settlement patterns.

SHIFTING SETTLEMENT PATTERNS IN THE SOUTHERN JORDAN VALLEY AND DESERT FRINGES OF SAMARIA DURING THE EARLY BRONZE AGE I PERIOD

This study deals with the unprecedented settlement activity during the Early Bronze Age I that has been recently recorded in the Jordan Valley and the desert fringes of Samaria. The increase in the number of sites primarily characterises the latter part of the period (Early Bronze Age IB), and is accompanied by two other important phenomena: population inroads into new regions, and the first appearance of fortified sites. A profound crisis at the end of the period resulted in the almost complete abandonment of the valley sites and the concentration of settlement along the eastern foothills of Samaria.

Sensitivity analysis from single-well ERT simulations to image CO2 migrations along wellbores

CO2 plume imaging is a required step in CO2 geological storage for both performance assessment and risk management purposes. This work has been performed in the frame of the CO2CARE project, and its aim is to develop tools and methodologies to monitor CO2 migration and verify the long-term well integrity after site abandonment. The timely detection of an anomaly is essential to perform a suitable remediation. For this purpose, downhole tools are permanently installed, but it is important to check the resolution and efficiency of the adopted techniques. In particular, this study investigates the possibility of using electrical resistivity tomography (ERT) to image CO2 migrations around observation boreholes through a sensitivity study.

Aggregation and dispersal based on social cues as a nest-site selection strategy in a resource-defence polygynandry mating system

Many animals must choose a nest site in order to reproduce. However, it is unclear how nest-site selection strategies vary across different mating systems. We must therefore explore nest-site selection strategies in a range of mating systems, including the interaction between resource-defence polygyny and polyandry (i.e. polygynandry). In this study, we imposed a re-settlement event in the terrestrial toadlet Pseudophryne bibronii and measured the influence of the spatial position of each male’s nest site with respect to rival males on the likelihood that it would be abandoned or receive eggs. We captured every calling male in a population, measured their breeding success and released them back into the breeding area. We then recorded the establishment and abandonment of nest sites by males over 26 consecutive nights. Spatial positioning did not have any significant effects on male-breeding success, supporting claims that females show less discrimination between nest sites when they are polyandrous and spread their eggs amongst multiple male nests. However, we found that males consistently selected nest sites according to a site’s spatial position, which suggests that fitness benefits unrelated to male breeding success (e.g. reduced mortality risk) might influence male nesting decisions. Overall, our study provides new evidence that the mating system adopted by a population can influence the cues that individuals respond to when selecting nest sites.

Creating novel urban grasslands by reintroducing native species in wasteland vegetation

In many areas of the world, grassland species have declined due to intensified agriculture and abandonment of unproductive sites. In rural areas, restoration approaches seek to counteract this loss. Additional potential for grassland restoration arises in urban settings, especially on large-scale wastelands isolated from suitable species pools.We explored the potential of urban wastelands for the development of low-maintenance meadows. We expanded on restoration approaches of rural landscapes by working with altered urban soils and existing wasteland vegetation. We tested if grassland species of regional provenances can be successfully reintroduced by comparing different restoration treatments: (1) transfer of a threshed seed mixture (Heudrusch) from local hay meadows, (2) seeding of species of regional provenances, (3) the same seeding combined with mycorrhizal inoculation.We revealed higher total species richness in all treated plots compared to the control, with similar proportions of grassland species. Both seeding treatments showed increased proportions of target species. The proportion of target species was stable in the seeding/mycorrhiza treatment and increased in the seeding only treatment from the second to the third year of the study to the same level. Urban soil features including stone content were negatively related to target species richness. In contrast, human-mediated impacts (e.g., dog intrusion) showed no significant effect on target species richness.Our experiment demonstrates that urban wastelands are suitable habitats for grassland species. Including extant soils and resident vegetation results in novel urban meadows with a considerable share of ruderal species but where rare grassland species are able to persist.

Microhabitat evaluation and utilization by a foraging predator

Sit-and-wait foraging is a distinct strategy that involves significant investments prior to prey encounters. However, the complexity of decisions involved in selecting, maintaining and abandoning ambush sites provides considerable opportunity for learning and flexibility, particularly for trap-building predators, such as web-building spiders. Most research into the behaviour of trap-building predators has focused on the initiation and completion of foraging bouts (site selection and site abandonment, respectively), and less consideration has been given to the ecological significance of behaviours that occur between these end points. In this study, we sought to determine whether an interim behaviour, flexible trap-construction, is a means of real-time decision making during foraging, and test a new hypothesis that site selection is not a single decision, but a cumulative series of several, distinct decisions based on evaluation of relevant site characteristics. In a laboratory assay, web-building spiders were allowed to choose between microhabitats with and without prey, and site utilization and web construction behaviours were evaluated over a foraging period, to determine how prey cues impact the evaluation and selection of foraging sites by predators. Spiders responded to prey availability across successive phases of site searching and web construction, demonstrating that multiple, distinct decision-making steps are involved in foraging site selection. These results indicate that site maintenance behaviours, such as multiple phases of trap construction, are an integral part of the decision-making framework of foraging predators.

Key Site Abandonment Steps in CO2 Storage

The European Commission published a set of Guidance Documents to assist countries and stakeholders to implement the EU Directive 2009/31/EC on geological storage of CO2. The main objectives of the CO2CARE project are closely linked to the three high-level requirements of the Directive with regard to post-closure transfer of liability of a storage site to the relevant competent authority: (i) absence of any detectable leakage, (ii) conformity of actual behaviour of the injected CO2 with the modelled behaviour, and (iii) the storage site is evolving towards a situation of long-term stability. Guidelines for regulatory compliance and “Best Practice” for site abandonment are being established by distillation and integration of all research findings into site closure and abandonment protocols. The work is based on 9 key injection sites in Europe and worldwide.

Disputed transformations: deindustrialization and redevelopment of Cologne's Stollwerck factory, 1970–1980

ABSTRACT:Urban development corresponds with economic shifts. In the second half of the twentieth century, when traditional forms of industrial production declined in many western cities, this posed new kinds of challenges. Cities were in need of a new economic base and at the same time had to cope with the abandonment of industrial sites. This article highlights the agency of local societies in shaping this process of deindustrialization and redevelopment. It interprets deindustrialization and redevelopment as a process of transformation which was open-ended and a matter of intense negotiation between diverging interests at the local level. In analysing the highly contentious case of the disused Stollwerck chocolate factory in Cologne, the article traces a complex set of site-specific factors of deindustrialization and redevelopment.

Investigation of proposed Norse irrigation channels and dams at Garðar/Igaliku, Greenland

It has long been proposed that various features within and beyond the confines of the Greenlandic settlement of Garðar, in modern Igaliku, reflect a medieval irrigation system with interconnected channels and cascading dams associated with Norse colonization and agriculture. These have rarely been investigated archaeologically or sedimentologically. After reviewing available evidence and the confusion surrounding terminology, this paper reports on excavations across three supposed irrigation channels. The lithostratigraphies of sediments located behind some of the proposed dams are also described and discussed. Although one of the excavated channels demonstrates convincing evidence for having been constructed (in part at least, through the presence of a vertical cut and the emplacement of flanking turf embankments), two of the channels are revealed as natural topographic features. It seems that if these were integrated into the Norse irrigation network then this was done without any further requirement for their modification or artificial enhancement. Deposits behind the dams were found to be shallow (~0.5 m deep) but contained sedimentary evidence for the former presence of standing water or waterlogged ground in the form of lake muds and peats. At one location (designated as Dam IX), radiocarbon dating of a stratigraphic change from lake mud to peat—indicating succession from open water to more terrestrial conditions—has been dated to cal. AD 1420–1620 [2σ] and may reflect the reservoir falling into disuse following site abandonment. While doubt is thrown on the existence of one dam identified by previous investigators, two possible new dam/reservoir features are presented.

A New Method for Trapping Chimney Swifts and Other Birds That Nest in Vertical Hollows

Previous Chimney Swift (Chaetura pelagica) trapping efforts relied on chimney-top box traps at large roost sites, which were disruptive and inefficient when targeting individual birds. I designed a hoop net for use at nest chimneys to trap individual breeding birds. I caught 13 swifts at 11 different sites in Guelph, Ontario, Canada over two summers with no site abandonment. This trap is superior for trapping individuals because it: (1) can be deployed quickly without scaling the chimney, (2) will work on chimneys of different sizes and shapes, and (3) minimizes disturbance to birds. My results indicate this net is an efficient, safe, and relatively simple method of trapping individual Chimney Swifts at their nest chimneys.

2600-1800 BCE Caral

<p>The Late Archaic Period of North Central Coast Peru witnessed increased El Niño events that transferred flood sediment from coastal valleys into ocean currents forming large barrier beach ridges. As a result, river drainage was impeded, bay infilling and coastal marshes appeared and sediment deposits covered coastal agricultural lands compromising their productivity. Many sites within the Supe Valley, with its ceremonial center at Caral, were based upon economic trade: marine resources from coastal sites exchanged with agricultural products from valley interior sites. Ongoing geomorphic processes compromising the valley economic base are one possible reason for valley site abandonment past 1600 BCE and indicate that dynamic landscape changes are vital research topics necessary to interpret the collapse of Late Archaic Period sites.</p><p>El Periodo Arcaico Tardío en la costa centro norte del Perú experimentó un incremento en los eventos de El Niño los cuales trasladaron sedimentos desde los valles de la costa hacia el Océano Pacífico; posteriormente, corrientes marinas movilizaron estos sedimentos y formaron grandes crestas y barreras de playa. Como resultado de este proceso, se impidió el drenaje de los ríos en la costa, las bahías existentes fueron colmatadas de sedimentos, y se dio la formación de ciénagas y pantanos costeros. Así mismo, sedimentos aluviales cubrieron las tierras agrícolas costeras comprometiendo así su productividad. Muchos asentamientos dentro del Valle de Supe y su centro ceremonial en Caral, estaban basados en el comercio económico: intercambio de recursos marinos entre los sitios costeros y los centros de producción agrícola en los valles interiores. Una de las posibles causas del abandono del sitio en el Valle de Caral después del 1600 AEC, es los procesos geomorfológicos que operaron en la zona y que afectaron directamente la base económica de los asentamientos en los valles; ello indica que los cambios en la dinámica del paisaje son un tema de investigación vital para la interpretación del colapso de los sitios arqueológicos Arcaicos Tardíos.</p>