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1.
Many attributes of present day soils can only be explained by reference to land management in the historic past. This is particularly well expressed in the plaggen soils which occur extensively on the north European plain. These deepened soils owe their dominant characteristics to the application from the 12th century of turf materials, often impregnated with dung. Similar deepening of soils can result from the disposal of urban waste. This paper discusses the results of soil research focused on a small Scottish town (Nairn). A soil survey revealed topsoils of over 1 m overlying fluvioglacial sands and gravels; such deepening is explained by the use of town waste on the burgh's arable lands from at least the 17th century up until the mid-19th century when an integrated sewerage system was installed. Micromorphological study of this deepened topsoil revealed the presence of many small black carbonaceous particles. Oxygen:carbon ratios were calculated from microprobe results as a means of confirming the carbonaceous nature of these particles. Soil phosphorus was primarily concentrated on the perimeter of these particles. The high quality of present day soils on the edge of the town is explained by the disposal of waste material, which included much carbonised material. This paper is the first to highlight the importance and potential of examining the gradation in soils from urban to rural contexts.  相似文献   

2.
X-ray fluorescence spectrometry (XRFS) was used in the analysis of A horizon soil samples collected from a former farming settlement and its associated area of infield (i.e. arable) located in the Central Highlands of Scotland. To date, XRFS has not been extensively used in geoarchaeological research, but in our study the simultaneous multi-element capabilities of this instrumental technique allowed the total concentrations of 25 major, minor, and trace elements to be fully quantified with acceptable levels of accuracy and precision. Included within this group of chemical elements are a number (e.g. Ba, Ca, P, Pb, Sr and Zn) that have proved to be of value to archaeological interpretation in earlier investigations undertaken in Scotland. In our preliminary work documented here, significant differences were found between the A horizon soils of former settlement and infield areas for 18 chemical elements. Subjecting the XRFS data—and three other measured variables: soil organic carbon (SOC), pH and A horizon depth—to discriminant analysis indicates that soils of former settlement and arable farming can be effectively classified according to their pH, SOC content and Ca, Cu, Mg, Rb, and Zn concentrations. The inference is that areas of former infield and settlement elsewhere at this study location in the Central Highlands may be able to be identified according to their soil chemical composition and use of discriminant function, even though the surface remains of pre-eighteenth century settlement sites are not readily evident today because they were constructed of perishable materials.  相似文献   

3.
Estate maps dating from the Russian general land survey of 1770–1781 are used to compile a historical map of land types, including cropland, forest, meadow, swamps, etc. The historical map is then compared with a modern soil map and a map of soil-forming parent materials to establish what effect, if any, past land types have had on present soil qualities. It is suggested that the better soils, in terms of drainage characteristics, were selected by man in the earliest stages of cultivation, and that poorer soils were put under the plow only subsequently as the crop area expanded. Some of these poorer soils have reverted, in the meantime, to grazing land. Soils long cleared of forest are found to have a higher carbonate horizon (effervescing with HCI) than soils more recently cleared of forest. The study area is Sapozhok Rayon of Ryazan' Oblast, southeast of Moscow.  相似文献   

4.
To help improve the well‐being of the local people, a joint Vietnamese‐UK team set out to establish a way of estimating soil and nutrient losses under different land management scenarios, using field data extrapolated through remote sensing and GIS, to obtain catchment‐wide estimates of the impact of land cover change. Immigration from remote provinces to the Dong Phu District of Binh Phuóc Province, about 120 km north of Ho Chi Minh City, has led to disruption of soil surface stability on easily eroded clayey sandstones, creating rapid nutrient depletion that affects crop yields and siltation in the channel of the Rach Rat river downstream. The poor farmers of the areas see crop yields drop dramatically after two or three years of cultivation due to the fertility decline. Soil loss varies dramatically between wet season and dry season and with ground cover. Erosion bridge measurements showed a mean loss of 85.2 t ha?1 y?1 under cassava saplings with cashew nuts, 43.3 t ha?1 y?1 on uncultivated land and 41.7 t ha?1 y?1 under mature cassava. The rates of erosion were higher than those reported in many other parts of Vietnam, reflecting the high erodibility of the friable sandy soils on the steep side‐slopes of the Rach Rat catchment. However, although the actual measurements provide better soil loss data than estimates based on the parameters of soil loss equations, a large number of measurement sites is needed to provide adequate coverage of the crop and slope combinations in this dissected terrain for good prediction using GIS and remote sensing.  相似文献   

5.
Current soils can have attributes inherited from land management systems in the past or previous environmental conditions. An important archaeological question is the extent to which the record of old agricultural practices can be retained in soils. This paper reports the results from examining soil thin sections collected from a range of old cultivated sites in the upper Bowmont valley, south east Scotland. The cultivated horizon was sampled from rigs and cultivation terraces dating from prehistoric to late medieval times. The main finding from microscopic analysis was the considerable impact of bioturbation as expressed in excremental pedofeatures. Results from point counting of these pedofeatures from 10 slides collected from an experimental site at Sourhope provided quantitative evidence on the extent to which bioturbation had occurred over the last 200 years. The rapidity by which micromorphological indicators of previous cultivation can be lost is thus demonstrated.  相似文献   

6.
对2000年、2005年及2010年的遥感影像图进行解译,得到3个时期的土地利用分类图,运用景观指数法和空间分析法等方法,对长株潭地区聚落的空间演化特征及动因进行分析,并分析了聚落与耕地之间的空间关系。结果表明:长株潭地区聚落的面积、数量规模和分布密度加速扩大,集中分布在高程200 m以下;聚落空间演化的自然动因是低地平原指向,而社会动因是人口规模的变化;提出耕地与聚落面积比指数(K)概念,根据K值的大小可以将耕地与聚落的空间组合关系分为3类地区:耕地资源紧缺区、耕地资源平衡区、耕地资源盈余区;聚落与耕地的空间转移关系可以分为两大类:持续稳定型和动态变化型;长沙市周边耕地转为聚落的趋势十分明显;聚落空间扩张对耕地的影响存在一个空间临界点,城市化速度越快,临界点的位置距离聚落越远。  相似文献   

7.
Results from soil chemical analysis have demonstrated enhanced concentrations of lead (Pb) associated with archaeological sites. However, interpretation of these Pb concentrations is difficult because of the multitude of possible Pb sources. This pilot study of an abandoned croft in Shetland suggests that Pb isotope ratios have the potential to identify sources of anthropogenic Pb. The results highlight two different Pb associations. The first includes hearth, house floor and house overburden soils, with end members of fuel materials and an unidentified material with a low (< 1.126) 206 Pb/ 207 Pb ratio. The second includes byre, kailyard (garden) and arable soils, with end members of hearth materials and local wind‐blown sand.  相似文献   

8.
In the context of an archaeological survey of the southern Argolid, Greece, studies have been carried out to elucidate the evolution of the landscape since its earliest known human occupation about 50,000 years ago. One of these studies was a detailed geological mapping of the late Quaternary alluvium and soils in the area. Dated by means of thorium-uranium disequilibria, archaeological finds, and historical information, seven periods of alluviation were identified, each of short duration relative to long intervening periods of stability and soil formation. The three earliest alluvial phases, falling before and during the last glacial interval, range from about 330,000 to 32,000 years in age. No alluviation accompanied the last glacial maximum around 20,000 years ago. In fact, a stable landscape persisted until about 4500 years ago, when debris flows and widespread aggradation in the valleys resulted from major slope destabilization and soil erosion, probably as a result of extensive land clearance in the Early Bronze Age. A subsequent stable period lasted through the many upheavals of the later Bronze Age, the Dark Ages, and the early historical period. It came to an end with a brief phase of alluviation between about 300 and 50 BC. Stability returned through the late Roman period, notwithstanding considerable expansion of the settled area. Another period of destabilization, this one marked by debris flows and hence major soil erosion, is poorly fixed in time, but probably coincides with expanded maquis clearance accompanying the resettlement of the area around AD 1000. Subsequent events of soil erosion and aggradation vary in nature and timing from one drainage to the next and, in some areas, continue today.Nature and chronology of the soil forming and alluviation events show that simple correlations with climatic events do not suffice to explain them. For the latter ones, past about 2500 BC, human activity seems to be the dominant cause, but once again the relation between cause and effect is not straightforward. Land clearing, or neglect of soil conservation efforts during economic downturns, appear to have a more devastating effect upon the landscape than do intensive land use or total land abandonment.  相似文献   

9.
Northwest China, including the provinces of Shaanxi, Gansu, Ningxia, and a small part of the Inner Mongolian Autonomous Region, was not only one of the earliest developed areas in history, but also one of the most ecologically fragile belts. The traditionally sustainable land reclamation and cultivation policies for the development of an agricultural economy adopted and implemented in administrations during different periods of the Qing dynasty, greatly raised farming and stock production. However, this led to imbalances in the originally fragile ecological environment. The negative effects such as rapidly expanding desertification, worsening water and soil erosions, increased cost of production, enlarged investment, vicious cycles and failing economy can serve as a lesson for contemporary development. __________ Translated from: Qingshi Yanjiu 清史研究 (Studies in Qing History), No. 1, 2004  相似文献   

10.
Soil profiles buried beneath earth banks of five abandoned enclosures, ranging in age from late Bronze Age to early 19th century AD, were compared with unburied profiles inside and outside the enclosures. Soil particle size analyses and micromorphological studies show that the banks were constructed of mixed topsoil and subsoil from adjacent ditches; on some banks the soil has begun to podzolize. At the two oldest sites (Dark Hat and Long Slade Bottom, which are late Bronze or Iron Age) the soils within the enclosures were homogenized, probably by occasional cultivation for cereal growing. At Dark Hat an ironpan has developed on the upper surface of a layer compacted by smearing during cultivation. The later enclosures, at Burley Moor (Anglo-Saxon), East Boldre (mediaeval) and Hatchet Gate (early 19th century AD), were probably used entirely for pasture. Pollen assemblages from the buried soils and overlying banks, and chemical comparisons of the buried soils with profiles inside and outside the enclosures together provide new evidence for a history of soil and vegetation changes over the past 2500–3500 years. Heathland vegetation associated with podzolic soils existed on plateau gravels before the late Bronze Age, but on other parent materials heath vegetation and acidic soils with incipient podzolization appeared only in later periods. The present patchy vegetation pattern of mainly deciduous woodland with open areas of ferny grassland and heath seems to have persisted since before the late Bronze Age. The most obvious human influences on the vegetation during the last 2000 years have been periodic temporary use of open areas and woodland clearings for protected grazing.  相似文献   

11.
12.
新时期中国农村土地综合整治逻辑体系框架   总被引:2,自引:0,他引:2  
在问题剖析和内涵辨析的基础上,从5个方面构建了农村土地综合整治逻辑体系框架。研究认为,新时期农村土地综合整治在指导理念上应以"理-工-管"等多学科交叉融合的基本理念为指导;在目标定位上应形成包含"现实目标、基本目标、中级目标、战略目标"的层次化目标体系;在宏观战略上应明确今后一段时期内综合整治的战略重点与方向;在统筹安排整治项目方面可按照"战略区-类型区-潜力区-项目区"的空间层次逻辑思路,从国家、区域、亚区、项目4个层级构建综合整治项目空间层级体系;在功能作用方面,可通过土地整治、空间重构、要素整合与机制创新来推进乡村转型发展和城乡一体化进程。  相似文献   

13.
This paper describes environmental impacts of tourism and recreation activities in the world heritage listed rainforests of northeast Australia and presents management strategies for sustainable visitor use of the protected area. Tropical rainforests are characterised by their low resistance and moderate to high resilience to impacts associated with human visitation. Visitor use in the World Heritage Area is mostly associated with walking tracks, camping areas, day use areas and off‐road vehicle use of old forestry roads and tracks. Adverse environmental impacts range from vegetation trampling, soil compaction, water contamination and soil erosion at the local scale through to spread of weeds, feral animals and soil pathogens along extensive networks of old forestry roads and tracks at the regional scale. Concentration of visitor use is the most desirable management strategy for controlling adverse impacts at most World Heritage Area visitor nodes and sites, and includes methods such as site hardening and shielding to contain impacts. For dispersed visitor activities, such as off‐road vehicle driving and long‐distance walking, application of best practice methods by the tourist industry and recreational users such as removal of mud and soils from vehicle tyres and hiking boots before entering pathogen‐free catchments, together with seasonal closure of roads and tracks, are the preferred management strategies. Retention of canopy cover at camping areas and day use areas, as well as along walking tracks and forestry roads is a simple, yet effective, management strategy for reduction of a range of adverse impacts, including dispersal of weeds and feral animals, edge effects, soil erosion and nutrient loss, road kill and linear barrier effects on rainforest fauna.  相似文献   

14.
There is more woodland in Britain now than for many centuries and considering many international climate change mitigation policies, woodland cover, both in Britain and internationally, is being promoted. However, neither the management of existing woodlands nor their expansion should be at the expense of important archaeological evidence. Due to the large number of known archaeological sites, the large areas of land with uninvestigated archaeological potential and the expanding woodland cover, suitable mitigation strategies need to be developed to allow preservation in situ of important sites. An understanding of how woodland soils and the buried archaeological resource interact is, therefore, essential. This paper utilises ongoing environmental research into the mineral weathering rates in forest soils and considers its application to artefact preservation. The study concludes that soil water pH, its movement, and the saturation of dissolved ions in the soil solution are major factors determining both mineral and artefact longevity. A simple guide to artefact longevity based on these properties is proposed and a geochemical model for predicting loss is tested. These tools could be applied to any soil or individual horizon irrespective of land-use.  相似文献   

15.
Isolation effects on the distributions of plant species in fragmented forests appear to be weak over tens to hundreds of years and strong over geological eras. The 250 km wide, 6.5 millennia old Bass Strait, and other millennium-scale disjunctions in the range of Eucalyptus regnans forests, were used to determine the effects of intermediate periods of isolation on plant species occurrence and composition. Three of six floristic communities were found on both sides of Bass Strait. The residuals from multiple regression models using climatic variables on the latitude vector were not explained by latitude, indicating negligible isolation effects from Bass Strait. However, there was a lesser compositional effect of disjunctions within land masses than between land masses, suggesting some effect of the larger barrier. No species that commonly occurred with E. regnans and were largely confined to wet forest exhibited absences from any region where the climate and soils were within their range. If areas isolated from each other for millennia can maintain their vascular plant biota, the expenditure of conservation funds on creating corridors to connect large areas separated by anthropogenic landscape modification might require more justification than it is currently afforded.  相似文献   

16.
The literature on bioturbation, both from the biological and archaeological points of view, is growing steadily. Available data suggests that ants and termites are responsible for the upward movement of soil/sediment particles and archaeological materials. It is argued that this could be the most parsimonious explanation for the stratigraphic data presented by Bueno et al. (2013), given the size range of displaced materials and the environmental setting, composed of a sandy soil in a savannah region.  相似文献   

17.
The South Downs in southern England have been farmed for 5000 years: the initial loess cover is now a thin, stony remnant as a result of erosion. During the 1980s, field monitoring of erosion events in an area of 36 km2 showed that average rates of erosion are low (0.5–5.0 m3 ha−1 yr−1), but that occasional storms result in losses of over 200 m3 ha−1 yr−1 on individual fields. On soils that are only 15 cm thick, such rates pose a threat to future farming. Almost all recent erosion has been on fields of winter cereals, which are bare in the wet autumn period. Of greater significance in the short term are the effects of soil-laden runoff (or muddy floods) on urban areas. Flood damage to property has been a regular event since the conversion of this area to winter cereals in the 1970s. Soil conservation measures have been negligible and flood protection has consisted mainly of engineering works and limited land-use change at sites where property damage has occurred. Conversion to grass under the Set Aside, and an Environmentally Sensitive Area (ESA) scheme, could be an effective soil conservation and flood protection approach. In the longer term, increasing stoniness of soils, the economic incentives for arable farming in marginal areas, and the success of legal proceedings relating to flood damage, will determine the future of erosion on the South Downs. Current farming systems clearly are unsustainable and would become more so under future climates without substantial site-targeted land use change.  相似文献   

18.
ABSTRACT

This research examines the chemical impacts to soils caused by the industrialisation (mechanisation and mass production) of sugar and rum manufacturing in the Caribbean during the eighteenth and nineteenth centuries. Soils and sediments excavated from Betty’s Hope sugar plantation (1674?1944) are chemically characterised by mild acid extraction and inductively coupled plasma-mass spectroscopy. These data are integrated with analyses of soil properties, including colour, texture, pH and organic matter, to examine activity patterns in areas associated with a large multi-use building dating to the period of industrialisation. Quantitative analysis of the data employs zero-order and partial linear correlation, multidimensional scaling, principal components analysis and spatial interpolation using semivariogram modelling and Kriging. The results reveal the locations of activity areas inside the building, which aids in understanding its role in sugar and rum production. The research also reveals evidence for soil contamination by heavy metals (lead and mercury), suggesting that plantation sites from this period may be polluted with industrial wastes. These findings have implications for activity reconstruction in the archaeological past as well as environmental and community health issues today.  相似文献   

19.
《Northern history》2013,50(1):97-115
Abstract

'The Costs of Parliamentary Enclosure in an Upland Setting: South and East Cumbria c. 1760–1860'. Although the costs of parliamentary enclosure have been shown to be high, attention has focused on lowland areas of England. This article examines the public and private costs of parliamentary enclosure in the old county of Westmorland, and adjoining areas of Cumberland and Lancashire, where most of the land enclosed was rough pasture, rather than open-field arable. The General Enclosure Act of 1845 greatly reduced public costs. These were in any case frequently financed by the sale of some of the land. On the other hand, private costs, including fencing and especially land improvement, were relatively high, pushing the overall cost of enclosure to substantial levels. The impact of such costs on Cumbrian society in the late eighteenth and early nineteenth centuries is then explored.  相似文献   

20.
Comparison between desert soils which have no history of cultivation with those which have been farmed near oases or by the use of some sort of irrigation shows that farming practices have left a permanent record in the soil profile. The salt content of the soil bears a direct relationship to the age of cultivation, the highest values being found in soils which carried Chalcolithic farming as far back as the 3rd millennium BC. Increased humus content and evidence of biological activity are also found in old cultivated soils, as well as inclusions such as clay brick fragments, pottery and charcoal.  相似文献   

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