Distribution Of Human Settlements Research Articles

Holocene shoreline displacement, land‐cover change and human settlement distribution on the southeast coast of Sweden

ABSTRACTIn this study, we investigate the interplay between relative sea‐level changes, the development of human settlements and land‐cover changes in the Västervik–Gamlebyviken region on the southeast coast of Sweden, an important archaeological area from the Mesolithic until recent times. The reconstruction of shore displacement was based on diatom analysis of radiocarbon‐dated sediment cores from three lake basins combined with previously published lake isolation data. The resulting curve was used to construct palaeogeographical maps for selected time windows. Land‐cover changes were inferred from pollen data from three lakes using the Landscape Reconstruction Algorithm with its two models REVEALS and LOVE. Our data suggest that people took advantage of the land gained due to an overall fall in relative sea level from ~35 to ~3 metres above sea level (m a.s.l.) over the last 10 000 years, interrupted by periods of transgression and highstands. A sea‐level regression of ~16 m occurred between 10 000 and 8500 cal a bp followed by an ~3–4‐m sea‐level rise, reaching ~22 m a.s.l. at ~7500 cal a bp, which corresponds to the maximum Littorina Sea shoreline in the area. The available archaeological findings for the Mesolithic and Early Neolithic (8950–5450 cal a bp) agree well with the shore displacement curve showing that settlements and human activities were concentrated along or above the shorelines as defined from our study. During the transgression after 8500 cal a bp, however, seasonal settlements were submerged (as shown by findings of polished stone tools and hearths buried in sand) and used again during the subsequent regression after 4600 cal a bp. The Iron Age (2450–900 cal a bp) corresponds partly to a highstand at ~11 m a.s.l. between 3600 and 2000 cal a bp and partly to a rapid regression of ~8 m between 2000 and 1500 cal a bp, and both periods coincide with known human activities along the contemporaneous shoreline. The rapid regression after 2000 cal a bp corresponds to an increase of both regional and local landscape openness and the beginning of a continuous record of crop cultivation.

Spatial Pathology of Earthquake Management in Salas Babajani County, Kermanshah, Iran

Background and objective Human settlements are formed and developed in a specific natural environment. Social, political, cultural, and economic systems that govern the societies can affect residential spaces. Therefore, the special natural and human habitats cause the formation of special spaces, which require their own management system. After the earthquake on November 12, 2017, in Salas Babajani County, Kermanshah, Iran, whose epicenter was Ezgeleh district, the presence of natural areas in the county caused the crisis management in this region to face special problems. In addition, the sectoral and centralized management structure governing the country and thus the Salas Babajani County added to the complexity of these problems and caused the residents of this region to suffer a deep crisis. The aim of the current study is a spatial pathology of earthquake management in urban and rural settlements of Salas Babajani County. Method This is a descriptive-analytical study. Data were collected using the documentary method and a researcher-made questionnaire. Participants were the residents of Salas Babajani County. Results The findings showed that the earthquake management in the County has a high compliance with the centralized and sectoral management model. In addition, it was found that the crisis management in the four stages (prevention, preparedness, response, and recovery) was in an unfavorable situation. the highest weakness was in the prevention stage and the lowest weakness was related to the preparedness stage. Conclusion Overall, the results showed that crisis management has worsened by moving away from the center towards the outskirts, especially towards the southwestern borders. In other words, by moving away from the political center of the County (Tazeh Abad district), the crisis management became very unfavorable. Also, it was found that the crisis management was greatly influenced by the spatial factors of elevation, land slope, transportation network, distribution of human settlements, and population density.

Analysis of Meanders and Bends of Lesser Zab River from Dalga VViilllage to Darbandi Rania

This study investigates the meanders of the Lesser Zab River in the study area, in terms of morphometric characteristics such as )length, width, direction, shape, area and symmetry of the meanders( and their distribution along the main river in the river valley through explaining the forcing factors in the creation of such shapes such as slope, geological structure, transported materials, flow of tributaries into the main river and tectonic activity in terms of geomorphic actions such as (carving, removal, transportation and sedimentation(, with the influence of human factors. Also, the phases of meanders development from north to south in the river valley are discussed. Furthermore, differences and dissimilarities of such formation can be seen between the periods 1972-2021; this is reflected in morphometric characteristics and geomorphic actions in all parts of the river basin. This research relies on various research methods such as deductive method, numerical methods and cartographic methods; using (ArcGIS.version.10.8), with the use of digital elevation model (DEM12.5m), to conduct detailed field work by the researcher. In the study area, 17 bends and meanders in the river have been identified, of which 7 bends were bends and 10 were meandering with the percent of meandering reaching (1.58), and the bend of Kewiya has the highest rate of twist, which reached (5.4). At the same time, the value of symmetry in the bend of Bekhre village is completely symmetric, because the value of each side (X) and (Y) is 49. For example, the length of the river for each of the years (2020,1984 and 2021) consecutively reached (32 km, 32.876 km, 31.7٢7 km), These changes will affect the size of human activities in the study area such as )distribution of human settlements, agricultural activities, poultry farms, fish ponds and industrial activities).

The Spatiotemporal Patterns of Human Settlement during the Longshan and Erlitou Periods in Relation to Extreme Floods and Subsistence Strategy in the Upper and Middle Qin River Reaches, Central China

Human settlement numbers have significantly changed before and after ~4000 cal. y BP in the upper and middle Qin River reaches, but the external and internal factors driving this change remain unclear. In this study, we examine changing spatial and temporal patterns of the Longshan and Erlitou settlements in relation to extreme flooding at ~4000 cal. y BP and a variety of subsistence strategies during the Longshan and Erlitou periods. The results indicate that settlement number, settlement distribution, and subsistence strategies exhibited obvious shifts between the Longshan and Erlitou periods, and the episode at ~4000 cal. y BP was an extreme-flood-rich interval within and around the Qin River Basin. During the Longshan and Erlitou periods, millet-based agriculture dominated local subsistence strategy, and ancient people would prefer to reside in the areas suitable for farming, causing the valley plains in the upper and middle Qin River reaches to contain most Longshan and Erlitou settlements. However, the frequent occurrence of extreme floods at ~4000 cal. y BP, in conjunction with intergroup conflicts due to a large amount of population immigration during the late Longshan period, is likely to have jointly decreased the settlement number and shrunk the spatial range of human settlement distribution. Subsequently, with the end of the extreme-flood-rich episode and the increasing proportion of higher-water-requirement foxtail millet in cropping structures of human subsistence strategy, more Erlitou settlements were distributed in the wetter valley plains of the middle Qin River reaches.

Changes in the Geographical Distributions of Global Human Settlements

In recent decades, the continuous growth in the population has significantly changed the area of human settlements across the globe. The change of human settlements has brought great challenges to human development, environmental change, resource allocation, and disaster prediction and prevention. In the current paper, we integrate data products provided by the European Commission, Joint Research Centre with multi-source remote sensing data to analyze the changing trends of global human settlements under varying geographical distributions from 1990 to 2014. The results demonstrate that on the global scale, human settlements are generally distributed in Europe, East Asia, Southeast Asia, South Asia, the eastern United States, the Gulf Coast and the coast of Oceania, with most of them distributed in urban agglomerations and coastal areas. Global human settlements have continued to grow over the past 25 years, mainly in East Asia, Western Europe and the United States. The area of human settlements in eastern Europe has been slightly reduced. The distribution of human settlements is affected by climate, water and terrain conditions. Humans were more likely to have settled in temperate regions with wetter climates, and most of the human settlements are located within 500 km of the coastline and 30 km of land-based water sources. Our results can provide insights into further investigations of the spatio-temporal dynamics of human settlements and its connections to ecological and environmental issues in a changing world.

Agricultural adaptations to topography and climate changes in Central China during the mid- to late-Holocene

The development of pre-historic agriculture and its determining factors have been extensively investigated in recent years. Based on the identification of charred seeds and radiocarbon dating, we found that foxtail millet-based agriculture dominated Neixiang County in Central China during the mid-late-Holocene. There were three different farming patterns in the Nanyang Basin, including rice cultivation in the plains, foxtail millet cultivation in the pediment plains, and broomcorn millet cultivation in the valleys. In addition, during the Neolithic-Bronze Age, the distribution of human settlements with rice cultivation matched with the climate pattern at 31.0–36.5° N in China. The emergence of rice cultivation had been facilitated by a significant increase in East Asian summer monsoon and increased precipitation in Central China since 8500 BP and gradually flourished during the Peiligang (8500–7000 BP) and Yangshao (7000–4500 BP) Period, corresponding to a relatively warm and wet climate. However, the average latitude of the human settlements with rice cultivation shifted southward to 33.29° N during the Longshan Period (4500–4000 BP) due to the cold climate brought by the “4.2 ka event.” Afterward, rice cultivation was basically not constrained by climate change, probably owing to the improved farming methods in the Bronze Age.

Human-associated scarcity of hosts for tsetse flies (Diptera: Glossinidae) is related to an increase in prevalence of trypanosome infection in flies in north-eastern Zambia.

Occurrence of nutritional stress (due to depletion of fat reserves) in tsetse flies, associated with inadequate levels of access to blood meals, enhances susceptibility of the flies to trypanosome infection. Thus, in a tsetse-infested area, a spatial gradient of reducing tsetse habitat quality is potentially a gradient of increasing prospects for occurrence of stress in tsetse flies. This study investigated prevalence of trypanosome infection in Glossina morsitans morsitans and G. pallidipes along a transect line hypothesised to represent such a gradient, in relation to the edge of the tsetse belt and distribution of human settlements. This was undertaken in three sites located in Lundazi, Mpika and Rufunsa districts, respectively, in north-eastern Zambia. Human settlement was concentrated at the edge of the tsetse belt in the Mpika and Rufunsa sites and evenly distributed along transect line in the Lundazi site. Tsetse fly samples were collected using black-screen fly rounds and Epsilon traps. Detection of trypanosome infection was by dissection and microscopy in Lundazi and Mpika sites and loop-mediated isothermal amplification (LAMP) test in Rufunsa site. Multiple logistic regression models were applied to determine whether the following factors, 'change in distance from edge of tsetse belt', 'tsetse sampling method' and 'sex of tsetse fly', had effect on 'prevalence of trypanosome infection' in the tsetse flies. Only 'increase in distance from the edge of tsetse belt' for G. m. morsitans was significantly associated with 'prevalence of trypanosome infection' in the flies, in the Mpika and Rufunsa sites. Distance was associated with reduced likelihood of infection with 'one or more subgenera of trypanosomes' and with 'Nannomonas trypanosomes', in the case of 'all sites collectively', 'Lundazi and Mpika sites collectively', Mpika site alone, and Rufunsa site alone. Per site, increase in distance entailed reduced prospects for Trypanozoon infection but only in the Mpika and Rufunsa sites. We conclude that in the Mpika and Rufunsa sites, increase in distance from human settlements entailed reduced likelihood of trypanosome infection, likely due to reducing tsetse habitat degradation, increasing availability of hosts, and hence increasing levels of nutrition and fat reserves, thus enhancing tsetse immunity against trypanosome infection.

Socio-Demographic Factors Influencing the Extent of Residential Green Spaces in Galle City, Sri Lanka

Due to increasing urbanization, the distribution of human settlements is changing and this has led to the rapid decline of vegetation cover in cities and townships. Urbanization tends to decrease the proportion of land that is dedicated to public green spaces. Therefore, residential gardens (private gardens) will need to play a major role in contributing to urban green space in future though presently little attention is given to their relative value and importance. Several factors influence the function of residential gardens in an urban area. The main objective of this paper is to evaluate the socio demographic factors that influence the size and presence of residential green spaces in an urban residential zone. As a case study, this research selected a primary residential zone in Galle City, Sri Lanka. Every housing unit (n=280) in a residential zone was surveyed to collect the data for multiple regression analysis. The analysis showed that factors such as land extent (LE), nature orientation (NO), perceptions about advantages of growing residential greenery (PA), perception about disadvantages resulting from residential garden (PDA), occupational status (husband and wife are not occupied) (D1), and their educational level (higher than degree) (D2) significantly affect to the extent of green area maintained by an urban residence. The relationship between extent of residential green space (EGA) and socio demographic factors can be explained by this model: EGA = 0.091 + 0.003LE + 0.060NO + 0.030PA – 0.040PDA + 0.198D1 + 0.240D2.

Factors influencing the evolution of human‐driven rocky desertification in karst areas

AbstractKarst rocky desertification has become one of the most important e‐environmental problems in China. The mechanisms of rocky desertification caused by land resources use, settlement expansion, population growth, and corresponding ecological responses are unclear. High‐resolution images of a typical karst plateau (Houzhai River Basin) acquired in 1978, 2005, and 2010 and data samples collected in the field in 2015 were used to quantitatively study the factors governing the evolution of rocky desertification driven by human activities. They comprehensively reveal its causes and influencing factors. Results suggest that the rocky desertification in the eastern and southern parts was, generally, more severe than in the western and northern parts of the study region. In the period from 1978 to 2015, no significant changes in the degree of (moderate) rocky desertification were observed. However, decreasing trends were observed for the no‐rocky areas, and slight decrease in rocky areas. The comprehensive indices of rocky desertification in 1978, 2005, 2010, and 2015 were 1.33, 1.24, 1.22, and 1.24, respectively. The rock outcrops in the no‐rocky desertification and potential rocky desertification areas were closely associated with the gravel content, slope gradient, and soil thickness, whereas those in the slight, moderate, and severe rocky desertification areas were primarily associated with the land use, gravel content, and slope gradient. The results suggest that the land use and human settlement were important factors determining the rocky desertification. The rocky desertification in the study area has improved during the period from 1978 to 2015. The main contribution to this improvement originated from the change in land use patterns. Therefore, reasonable management of land use and human settlement distribution can effectively reduce the rocky desertification in a karst area.

Spatial characteristics of physical environments for human settlements in Jinsha River watershed (Yunnan section), China

In recent years, natural disasters such as earthquakes, landslides, mudslides, collapses, drought, and extreme temperature occur frequently in Yunnan Jinsha River watershed, causing deterioration of physical environments for human settlements in some areas of the watershed. Although several studies have addressed individual environmental elements in the study area, efforts for integrated analysis of environmental factors and human settlements are still lacking. Therefore, it is important to identify the spatial distribution of physical environments for human settlements to support population distribution planning. This study includes 10 factors (topography, landform, vegetation, elevation, fault, rock, soil, earthquake intensity, temperature, and precipitation) as indicators for the assessment of human settlement suitability based on the analytic hierarchy process and grey correlation methods. Geographic information system functions were used to help understand the spatial distribution of human settlements and the causal factors. This study reveals different spatial units of the watershed suitable for human habitation from the viewpoint of physical environment and provides recommendations for urban planning and siting, land use planning, and disaster mitigation in the watershed.

Breaking new ground in mapping human settlements from space – The Global Urban Footprint

Today, approximately 7.2 billion people inhabit the Earth and by 2050 this number will have risen to around nine billion, of which about 70% will be living in cities. The population growth and the related global urbanization pose one of the major challenges to a sustainable future. Hence, it is essential to understand drivers, dynamics, and impacts of the human settlements development. A key component in this context is the availability of an up-to-date and spatially consistent map of the location and distribution of human settlements. It is here that the Global Urban Footprint (GUF) raster map can make a valuable contribution. The new global GUF binary settlement mask shows a so far unprecedented spatial resolution of 0.4″ (∼12m) that provides – for the first time – a complete picture of the entirety of urban and rural settlements. The GUF has been derived by means of a fully automated processing framework – the Urban Footprint Processor (UFP) – that was used to analyze a global coverage of more than 180,000 TanDEM-X and TerraSAR-X radar images with 3 m ground resolution collected in 2011–2012. The UFP consists of five main technical modules for data management, feature extraction, unsupervised classification, mosaicking and post-editing. Various quality assessment studies to determine the absolute GUF accuracy based on ground truth data on the one hand and the relative accuracies compared to established settlements maps on the other hand, clearly indicate the added value of the new global GUF layer, in particular with respect to the representation of rural settlement patterns. The Kappa coefficient of agreement compared to absolute ground truth data, for instance, shows GUF accuracies which are frequently twice as high as those of established low resolution maps. Generally, the GUF layer achieves an overall absolute accuracy of about 85%, with observed minima around 65% and maxima around 98%. The GUF will be provided open and free for any scientific use in the full resolution and for any non-profit (but also non-scientific) use in a generalized version of 2.8″ (∼84m). Therewith, the new GUF layer can be expected to break new ground with respect to the analysis of global urbanization and peri-urbanization patterns, population estimation, vulnerability assessment, or the modeling of diseases and phenomena of global change in general.

Temporal-spatial variations of human settlements in relation to environment change during the Longshan culture and Xia-Shang periods in Shanxi Province, China

Abstract There is much evidence that shows that dramatic global cooling and drying events took place at approximately 4.0 ka BP. This was also the case for Shanxi Province, China. Accordingly, we investigated changes in the distribution of human settlements during the Longshan culture and Xia-Shang periods (from 4.4 ka BP to 4.0 ka BP and from 4.0 ka BP to 3.1 ka BP, respectively) in different regions of Shanxi Province. In this study, we discuss the human response to the dramatic cooling and drying events that took place during this historical period. Our analysis shows that such dramatic cooling and drying events resulted in an overall decrease in the number of human settlement sites in three regions of Shanxi Province under different climatic conditions. These three regions are also comprised of different landform types and elevation ranges. We found that changes in settlement sites mainly resulted from differences in climate sensitivity in accordance to different latitudes and elevations and from differences in the frequency of human conflicts caused by the dramatic climate changes in areas of different settlement densities.

Potential and Limitations of Radar Remote Sensing for Humanitarian Operations

Methods of earth observation deliver quick and reliable information covering large areas, which can be used for the management of natural disasters and humanitarian crises. However, optical sensors reach their limits in areas affected by cloud cover or atmospheric haze, while radar satellites are predominantly unaffected by atmospheric conditions. This paper discusses the application of radar imagery for the assistance of humanitarian operations. The opening section describes the need for complementary information gained from radar data as well as the challenges which arise when working with imaging systems. Subsequently, examples for the use of various sensors are given based on our own findings, and a literature review for various application domains. These include the monitoring of natural resources, the distribution of human settlements or dwellings, and the retrieval of hydrologic parameters. Against this background, limitations and how they were handled in selected studies are discussed. A summary reflects the findings in the light of new developments and discusses challenges for the future.

RELATIONS BETWEEN GRACE-DERIVED WATER STORAGE CHANGE WITH PRECIPITATION AND TEMPERATURE OVER KAIDU RIVER BASIN, CHINA

Abstract. Water is essential for human survival and well-being, and important to virtually all sectors of the economy. In the aridzone of China’s west, water resource is the controlling factor on the distribution of human settlements. Water cycle variation is sensitive to temperature and precipitation, which are influenced by human activity and climate change. Satellite observations of Earth’s time-variable gravity field from the Gravity Recovery and Climate Experiment (GRACE) mission, which enable direct measurement of changes of total terrestrial water storage, could be useful to aid this modelling. In this pilot study, TWS change from 2002 to 2013 obtained from GRACE satellite mission over the Kaidu River Basin in Xinjiang, China is presented. Precipitation and temperature data from in-situ station and National Satellite Meteorological Centre of China (NSMC) are analysed to examine whether there is a statistically significant correlation between them.

RELATIONS BETWEEN GRACE-DERIVED WATER STORAGE CHANGE WITH PRECIPITATION AND TEMPERATURE OVER KAIDU RIVER BASIN, CHINA

Water is essential for human survival and well-being, and important to virtually all sectors of the economy. In the aridzone of China’s west, water resource is the controlling factor on the distribution of human settlements. Water cycle variation is sensitive to temperature and precipitation, which are influenced by human activity and climate change. Satellite observations of Earth’s time-variable gravity field from the Gravity Recovery and Climate Experiment (GRACE) mission, which enable direct measurement of changes of total terrestrial water storage, could be useful to aid this modelling. In this pilot study, TWS change from 2002 to 2013 obtained from GRACE satellite mission over the Kaidu River Basin in Xinjiang, China is presented. Precipitation and temperature data from in-situ station and National Satellite Meteorological Centre of China (NSMC) are analysed to examine whether there is a statistically significant correlation between them.

Using a Binomial Mixture Model and Aerial Counts for an Accurate Estimate of Nile Crocodile Abundance and Population Size in the Kunene River, Namibia

The Nile crocodile,Crocodylus niloticus, is found throughout sub-Saharan Africa, including Namibia, Botswana and Angola. The species was transferred from CITES Appendix I to Appendix II in 2004, although it is recognized as peripherally endangered in Namibia due to diminishing habitat availability primarily from human encroachment. In 2013, a species management plan was approved in Namibia to assess the management of the Namibian Nile crocodile populations. During 2012, an aerial survey was conducted to provide an estimate of Nile crocodile population numbers. A recently developed N-mixture model for estimation of abundance and spatial variation was used. Detection probability correlated to animal size and environmental covariates. Our data also suggest that small crocodiles are easier to detect during the spring. The abundance for different size classes was influenced by river complexity (vegetation, depth, channels) and the distribution of human settlements. An estimated 806 individuals were counted alo...

A dynamic model for population mapping: a methodology integrating a Monte Carlo simulation with vegetation-adjusted night-time light images

Population is attracting increasing attention as a driver of resource overexploitation, environmental degradation, loss of biodiversity, and other environmental challenges. Timely and accurately updating maps of population distribution are thus urgently needed. Images of night-time lights from the Defense Meteorological Satellite Program Operational Linescan System (DMSP-OLS) have been used for years in population mapping as an alternative to human settlement distribution. The capacity of night-time light images for gridding populations, however, is compromised by the dual effects of saturation and overglow. Static models of the human settlement index (HSI), elevation-adjusted human settlement index (EAHSI), and vegetation-adjusted night-time light urban index (VANUI) have been developed to counteract these negative effects by using constant coefficients. The static models, however, retain disadvantages due to the negative effects of the high variation of socio-economic backgrounds in different study areas. In this study, we integrate Monte Carlo simulation with the above three static indices and propose the dynamic model VANUI Supported by Monte Carlo Simulation (VANUIMCS) for mapping the population of Liaoning Province, China. We assess the accuracy of the simulation using data for 60 counties and 1251 townships. The VANUIMCS improve the accuracy of population mapping, with the mean percentage errors of 19.43% at the county level and 43.19% at the township level.

Frontiers of Disease: Human Desire and Environmental Realities in the Rearing Of Horses in Nineteenth and Twentieth-Century South Africa

Horses have played an important economic, military and cultural role in South African history. However, disease has always posed a threat to their survival. Horsesickness, a viral infection transmitted by midges from the genus culicoides, is endemic in much of the country but has historically assumed epizootic proportions in certain years. In the lowveld and Zululand nagana (trypanosomosis), spread by tsetse flies, has killed both horses and cattle and affected the distribution of human settlement and agricultural activities. In addition, much of South Africa is very arid, yet has rich floral taxa. Several plants, such as Senecio spp. are highly toxic to horses, but in times of drought and fodder shortages, equines are faced with the choice of starvation or potentially succumbing to toxicosis by eating poisonous weeds. This paper considers the environmental impact of these three types of horse diseases in South Africa and explores the scientific and ecological investigations undertaken since the late nineteenth century to try to control them. Research into horse diseases brought together the laboratory and the field and raised important questions about the part played by environmental factors, as opposed to just germs, in the distribution of livestock infections and the ability of farmers and scientists to tackle them effectively.

The Numbers and Distribution Patterns of Large Mammals in the Ruaha- Rungwa Area of Southern Tanzania

(1) An aerial census of Ruaha National Park, Rungwa and Kizigo Game Reserves, and part of the proposed Mloa-Ilambi Game Controlled Area is described. (2) Zebra, eland, sable, and hartebeest were virtually restricted to the miombo woodlands. Impala and kudu were most common in the rift valley sector of the census zone. Elephants, buffalo, and giraffe occurred throughout the entire area. (3) The 31 500 km2 census zone carried one of the largest elephant populations in Africa, an estimated 43 685 ? 9254 elephants, of which 24 625 ? 7132 were estimated to occur within Ruaha National Park (10 200 km2 in area). The densities of elephants and the combined densities of the other large herbivores were highest in the National Park and lowest in the Game Controlled Area. (4) Within the National Park, comparisons with earlier counts showed an apparent increase in elephant density of 8-10% per annum since 1965. Of the large herbivores, elephants alone showed a significant increase since the 1972 census and only elephant distribution was significantly affected by the distribution of human settlement and hunting. The increase in elephant numbers within the National Park is probably the result of the change in human distribution in the region and a period of higher rainfall.

Climatic change and early population dynamics in the Southwestern United States

It is becoming increasingly apparent that the pattern of early human occupation of the Southwestern United States was strongly influenced by the major paleoclimatic events of the period 9500 B.C. to A.D. 700. The size of human populations and the distribution of human settlement at both the regional-topographic and large-scale areal level, known from archaeological research, are directly correlated to climatic change documented by the evidence of geology and palynology.The effect of climatic change is felt through the actions and reactions of the economic subsystem and its linkages with other subsystems. These reactions reflect not only the character of the climatic stimulus but also the existing state of the cultural system. Alternate reactions include direct systemic readaptation to the changed environment (through changed technologies, methods of population control, etc.); or small scale or large scale relocation of populations in different local niches, regions, or areas whose character most closely approximates the conditions to which the cultural system was initially adapted.