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1.
废灶兴垦是清末民初苏北沿海土地利用变化最为显著的特征。本文拟对其发展历程进行深入的探讨 ,以期更为全面地揭示其自西徂东、由南而北逐步推进的“时空”演变特征  相似文献   

2.
Geostationary satellites provide measurements over a wider geographical area with high temporal sampling, while microwave measurements are more accurate but sparse. For continuous monitoring of the Indian monsoon, geostationary platform would be ideal. In this study, INSAT (Indian National Satellite) Multi‐spectral Rainfall Algorithm (IMSRA) has been used for the estimation of rainfall from Kalpana‐1 very high resolution radiometer (VHRR) measurements. IMSRA benefits from the relative advantages of infrared and microwave sensors and is operational at the India Meteorological Department (IMD). In this paper, rainfall is estimated over India at meteorological sub‐divisional scale during the south‐west monsoon season of 2009 using Kalpana‐1 satellite measurements. This is the first experimental attempt to generate meteorological sub‐divisional scale rainfall maps using Kalpana‐1 satellite measurements. The rainfall maps for the south‐west monsoon season over the Indian land region are successfully utilised as a space input for the drought monitoring of the year 2009. The results have been compared with the IMD gauge‐based accumulated rainfall maps at monthly and seasonal time scales. The qualitative comparison suggests that rainfall maps generated using the present methodology is in good agreement with the IMD rainfall maps. The quantitative comparison of the sub‐divisional monthly accumulated rainfall shows a correlation of 0.77 and standard error of 71 mm over the non‐orographic regions, whereas a correlation of 0.60 and standard error of 117 mm is observed over the orographic regions. The present study shows that Kalpana‐1 satellite‐based rainfall estimates (IMSRA technique) can act as a complementary tool for the monsoon monitoring over the Indian meteorological sub‐divisions and can be used for various meteorological and hydrological applications.  相似文献   

3.
Abstract

This article explores the management practice of protection notices, fredlysning, in the traditional practice of eider down harvesting in Northern Norway. Previously, private initiatives were legitimate for protecting land and resources from public utilization, while today only the state authorities have this privilege. By juxtaposing empirical material from current eider down harvesting activities with childhood memories of growing up in this area during the 1960s, and available legal documents, the author finds that some quite radical changes have tacitly taken place, indicating rather tense dilemmas concerning local perceptions of land use issues. Analytically, Olwig's distinction between customary and natural law is used as a tool for addressing the political dimensions of the landscape concept historically. In this perspective, fredlysning fluctuates in and out of codified law through the centuries, and under growing impact of natural law rationale. Land issues, both concerning property rights and public access and use of the common resources of the outlying fields, utmarksressurser, are here understood as very powerful means to bind the people to the land, as a way of transforming the legitimate scale of polity, of building bonds to the nation.  相似文献   

4.
Abstract

Perfected by biologists, the analysis of dental cementum rings allows us to know the precise age of the animals studied as well as their season of death. Cementum deposits are layers of various density formed regularly during the animal's life. Large, translucid deposits (observed with polarized light), growing during the good season (spring, summer, autumn), alternate with thin, opaque ones that grow during the bad season (winter). Used to study two French Azilian sites, La Fru and Campalou, this method gives us a better understanding the hunting behaviour of these two human groups. Thus, the Azilian hunters who established their camp in the La Fru and Campalou rockshelters hunted around the site, killing ibex. However, these two groups of predators preferred red deer. Taking advantage of the hunting opportunities offered by the environment, hunters at both sites made opportune captures to the detriment of summer herds of hinds and young. Also, at Campalou, they continued their predation during the rut, concentrating on young animals, probably young males temporarily alone because of the mating season.  相似文献   

5.
Abstract

The cyclical use of sites and locales over decades, centuries, and even millennia is an important aspect of hunter-gatherer land use that is rarely considered in studies that focus on a single annual cycle. The long-term perspective provided by archaeological data can be used to delineate persistent land use patterns and contribute to an understanding of the complexity of hunter-gatherer behavior. Mid-Holocene Wyoming housepit data document persistent land use over at least a 2000-year period at three spatial scales—the reuse of housepits, reuse of sites containing housepits, and use of different sites within the larger region. Slab-lined cylindrical basins at many sites in southwest Wyoming provide evidence for stable long-term land use during the middle Holocene. The focal point of this pattern was probably a predictable resource, possibly some type of root plant that would have been available during the dry middle Holocene.  相似文献   

6.
Abstract

The interest in heritage as a tool for destination development has recently been substantial in Sweden, especially when it comes to receiving World Heritage (WH) status. The possibility of using the WH brand in developing tourism products and marketing destinations has great potential for many heritage destinations. The aim of this paper is to discuss innovation processes within heritage tourism. The focus is on the role of WH status as a factor influencing innovative practices at different Swedish WH sites. This study uses qualitative methods, such as interviews and analysis of written material from five selected Swedish WH sites, with in-depth analysis of the Great Copper Mountain in Falun. To what extent does WH status change the preconditions for tourism development at WH destinations? What is the role of institutional frameworks in this process? This paper will show how WH may facilitate tourism innovation mainly through developing new products and marketing strategies, but also by institutional innovations concerning new forms of collaboration and networks.  相似文献   

7.
Parks Canada began the Northern Satellite Monitoring Program in 1997, with the objective of tracking large‐scale vegetation variation in Canadian ecosystems and helping land managers to develop appropriate management practices in response to climate change. Under this program, a sequence of 10‐day composite Advanced Very High Resolution Radiometer (AVHRR)‐derived Normalized Difference Vegetation Index (NDVI) data from 1985 to 2007 was examined to study seasonal and inter‐annual relationships between vegetation and climate data over Canadian ecosystems using statistical and wavelet analysis. Statistical analysis showed that temperature was the principal driver for seasonal variability in greenness, explaining more than 70 percent of seasonal variation in vegetation for most Canadian ecozones. In comparison with temperature, the relationships between NDVI and precipitation were weaker but still significant. Maximum annual NDVI showed increasing trends in Canadian ecozones during the study period, although increasing rates were spatially heterogeneous. Wavelet analysis confirmed that inter‐annual variation in NDVI was different at two ecozones in Canada. NDVI variation in the Northern Arctic was significant at scales of 3–4 years from 1997 to 2001, which was associated with temperature and precipitation variation. Comparatively, NDVI variation in the Boreal Shield was significant at scales of 5–8 years from 1991 to 1999, but did not correspond with climate variation.  相似文献   

8.
In west‐central Neuquén Province, Argentina, in the area around Estancia Llamuco, west of Zapala, south of Las Lajas and north‐east of Lago Aluminé, there are multiple primary and secondary sources of obsidian. Primary sources occur within the south‐east extension of the Plio‐Quaternary volcanic chain that runs from Copahue volcano through Pino Hachado. Secondary sources include river‐bed gravels within the valleys of Arroyo Cochicó Grande and Río Kilca as far south as where this river joins with Río Aluminé, and the Quaternary fluvial–glacial sediments cut by the valley of Río Covunco as far east as Portada Covunco. Visually variable obsidians from these two secondary sources include homogeneous black and grey‐translucent types, porphyritic and banded types, and an abundant quantity of oxidized red and black obsidian. However, all these visually distinct obsidians have similar and unique chemistry, with Ba between 220 and 340 ppm, different from any other obsidians previously reported from Neuquén, which all have Ba > 500 ppm, as do obsidians from sources to the north in Mendoza and to the west in Chile. This chemical distinctive obsidian has been exploited and transported over a wide area, beginning prior to 4000 bp , and occurs in local archaeological sites, as well as sites ≥ 300 km to the north‐east in La Pampa Province, ~430 km to the south in Chubut Province, and >75 km to the west across the Andean drainage divide in Chile.  相似文献   

9.
Grass silica short cell phytoliths were sampled from the four lowermost archaeological strata in excavation 1 at Wonderwerk Cave and offer an independent record of climatic change during an episode of Early Stone Age hominin occupation at the cave. Linked to differences in growing season temperature and the geographic distribution of C3 and C4 grasses in southern Africa, fossil grass phytoliths were used to trace palaeoenvironmental shifts at the site. The results suggest that Early Pleistocene environmental conditions at the cave fluctuated: between wetter and drier summer–rainfall growing conditions (C4) towards the end of the Olduvai subchron and the beginning of the subsequent interval of reversed polarity, to mostly dry and cooler winter–rainfall growing conditions (C3), that continued throughout the interval. It ended with a shift towards increased summer rainfall aridity at around one million years ago. The fluctuation between markedly wetter and drier C4 conditions at the cave (NADP-me grass types vs. NAD-me grass types) does not support the premise that the expansion of C4 grasslands was always coupled with increased aridity.  相似文献   

10.
This article presents the results of the excavation of a residence dated between the second and fourth centuries AD, constructed over the ruins of the South Arabian town of Makaynūn, in central Hadramawt (Yemen). The building yielded a large quantity of material including objects proving contacts between the central Hadramawt and regions located to the north‐east, such as central Oman, the Gulf area and India.  相似文献   

11.
Based upon an ethnographic study of two land disputes in the rural Assamese district of Karbi Anglong (India), this article challenges the idea that the entry of new institutional players, with their multiple sets of rules, inevitably leads to open institutional conflict. Although a wide range of political actors are involved in the regulation of land tenure in Karbi Anglong, they cannot be regarded as institutional structures ready to undercut one another. As in other parts of Northeast India, none of the claimants of public power involved —‘the state’, ‘the rebel’ or ‘the chief’— attain full sovereignty, which forces them to exercise authority predominantly through practices of negotiation and accommodation, and only selective contestation. If open institutional conflict does occur, as in the Dhansiri forest and the Singhason plateau cases studied here, this is due to the fact that one of the institutional players has overstretched and attempted to exercise authority beyond its realm of power. This article thus argues for a more agency‐oriented method of analysis in the study of land relations. The focus on everyday interactions between ‘the state’, ‘the rebel’ and ‘the chief’ in Karbi Anglong is a first attempt in that regard.  相似文献   

12.
Abstract

Monitoring and understanding of land use/forest cover dynamics as well as the factors affecting the changes in land use/forest cover are necessary for the sustainable management of natural resources. This study analyzes the spatial and temporal changes in land use and forest cover patterns in a typical mountain forest area in the Torul State Forest Enterprise area of Northeastern Turkey. The investigation evaluates the temporal changes of the spatial structure of forest conditions through the spatial analysis of forest-cover type maps from 1984 and 2005 using GIS and FRAGSTATS. The evidence presented here showed that there were drastic changes in the temporal and spatial dynamics of land use/forest cover, and between 1984 and 2005 there was a net increase of 19.9% in total forested area. Productive forest area increased by 3161 ha, although degraded forest area increased 9216 ha. In examining the changes of crown closure and development stages of the forest ecosystem during the study period, the forest stand area with low crown closures increased. The regenerated area increased because of regeneration activities while the other development stages were left to grow to older development stages in the period. These results regarding the crown closure and development stage show that forest quality has increased, and this is partly due to emigration of the rural population in Torul. In terms of spatial configuration, the landscape structure in Torul, the State Forest Enterprise area, changed substantially over the 21-year study period, resulting in fragmentation of the landscape as indicated by large patch numbers and smaller mean patch sizes, owing to heavy timber subtraction, illegal cutting, and uncontrolled stand treatments.  相似文献   

13.
Daily winter (December, January and February) precipitation variability over mainland Northern Scotland (1994–2004) is analysed using 99 rain gauges. Principal component analysis (PCA) is used to identify four main patterns of rainfall variability that collectively account for nearly 75% of the variance. The most important pattern (PC 1) shows a west to east decline in rainfall; and is associated with a westerly wind flow, orographic enhancement and rain shadow effects. PC 2 shows a south to north decline in rainfall, a distribution that is generated disproportionately by southerly winds and a more southerly storm track than PC 1's pattern. PC 3 produces the most rainfall in Aberdeenshire and the least in Inverness-shire and Argyll. This spatial distribution is caused mostly by south-easterly flows, with the lowest pressure occurring in eastern Scotland or over the North Sea. PC 4 exhibits a localised precipitation maximum in Nairnshire and Moray, which tends to occur on days with a north to north-easterly wind. Cluster analysis is used to identify six rainfall regions, with regionalisations being derived for each wind direction. The most important sub-division in the region's rainfall climatology is between Aberdeen and Banff and the remainder of the mainland; rainfall variability over time in these two eastern counties thus differs considerably from other parts of Northern Scotland. The Caithness Plain also emerges as a distinct region despite its small area. Distinct rainfall regions are most evident on days when the wind blows from the westerly quadrant.  相似文献   

14.
Accounts of European explorers between 1623 and 1880 indicate that fires were lit by Aboriginal people on Cape York Peninsula in northeast Australia throughout the dry season (May–October). Diaries kept by three generations of pastoralists in the Musgrave area (1913–1952, 1953–1974 and 1976–1992) show that burning activities were largely confined to a two to six week period between May and early August. The timing of burning depended on the amount and date of cessation of wet season rainfall. More rarely, ‘storm‐burning’, burning under hot conditions within a few days of the first heavy rains of the wet season, was undertaken. Long‐term pastoralists felt a responsibility to use fire wisely and had a detailed knowledge of the role of fire in land management. Their decisions to burn were based on the extent of grass curing, and soil and weather conditions, all of which affected the extent of each burn. They used early dry season fires mainly to maintain forage and control cattle movements. Storm‐burns were reputed to control woody weeds, but were used infrequently because of difficulty in controlling their spread and uncertainty as to when the next rains would stimulate new grass growth.  相似文献   

15.
Abstract

Over the last three decades, significant quantitative information on prehistoric diets has come to light from a variety of locations in the Caddoan archaeological area, a region encompassing eastern Oklahoma, western Arkansas, northeast Texas, and northwest Louisiana. Most of this research is based on macro-botanical and faunal remains analysis. As an additional line of evidence for the growing body of botanical and faunal data, stable carbon and nitrogen isotopes in bone collagen were analyzed from 82 human and faunal samples from the Arkansas basin and Ozark Highlands in eastern Oklahoma. The research investigates the role of maize in diets through time and across sex and status dimensions. Spanning six phases, within the time range 300 B.C. to A.D. 1650, mean δ13C values increase from –19.2 to –12.7 parts per million ‰. Although present prior to A.D. 1000 substantial increases in the use of maize do not begin until the Harlan phase (A.D. 1050–1250). Even with increased use, maize never dominates the diet to the extent seen in Mississippian period sites farther east.  相似文献   

16.
Abstract

Backfill material from a 12th- to13th-century quarry, north of Wallingford, south Oxfordshire, comprises sandy loam overlain by Cretaceous (early Cenomanian; Mantelliceras mantelli Macrofaunal Biozone) Glauconitic Marl Member, of the West Melbury Marly Chalk Formation as identified by its abundant, biostratigraphically useful, foraminifera and ostracods. A local outcrop source of the Glauconitic Marl Member, less than 1 km north of the quarry pit, is the likely provenance of this material, and a contemporaneous road, which was discovered adjacent to the medieval quarry by magnetometer surveys and archaeological excavation, would have aided its transportation, into the town via the North Gate. We hypothesise that the use of a calcareous marl to overlay sandy loam deposits probably encouraged land restoration when the quarried area was returned to pastoral agriculture.  相似文献   

17.
Historical accounts and assessments of Lake Ontario's north shore during the late seventeenth century generally describe the area as an abandoned battleground and devasted “no-man's land”. The impression is built of English and particularly French views that this was an area no longer useful as a major source of furs. To the Iroquois the land was anything but devastated. Whereas they bypassed the territory in their constant search for furs to the north and west, the north shore, strategic and fertile, became a trading, agricultural, and even settlement frontier. A reassessment of the written documents and largely neglected maps of the period suggest that the Iroquois occupation of the north shore was highly ordered and based on traditional trade routes and tribal territorial claims. It was an extension of the homeland. But innovations in subsistence, settlement, and lifestyle did occur. The study of expansion to the north shore provides valuable insights into the delicate balance between the forces of change and continuity in post-contact Iroquois society.  相似文献   

18.
Rainfall during six days of monsoonal activity in the 1988/89 wet season is examined in terms of the influence of synoptic scale winds on mesoscale rainfall activity over the Townsville coastal plain (3450 km2). The resulting rainfall patterns. which were based on observations from a dense mesoscale network of 133 gauge points. are presented as isohyetal maps of twenty-four hour totals for each day in the study period. The study has shown that the distribution of rainfall is related to the influence of synoptic scale wind vectors, which provide upper level steering of convective activity. In addition. the interaction between local winds and synoptic circulation is deemed important for inducing convergence and precipitation. Rainfall generated is then directed by the prevailing upper synoptic flow. Orographic effects also appear to be significant, in that rainfall distribution tends to favour slopes on the windward side of the synoptic scale winds. The rainfall patterns described are probably typical of many of those that occurred throughout the 1988/89 wet season, due to the likely persistence of these mesoscale precipitation mechanisms. Similar mechanisms are also likely to occur over the study area in other wet seasons and elsewhere in the seasonally wet and dry tropics.  相似文献   

19.
Land is intertwined with politics: both as a sine qua non for the territorial state, as well as a spatially limited natural resource through which geopolitical power and advantage are articulated and enacted. This remains the case, notwithstanding the emergence of global and planetary frameworks for land management towards collective environmental and developmental goals. Indeed, such frameworks contend with narratives and practices that not only treat land as a strategic national resource, but entangle it with the very ontology of statehood itself. This study examines such state-natures through the case of Russian agricultural land use. Analyzing governmental discourse from 2000 to 2020, it examines how in the extensive cultivation of agricultural land has come to be a hallmark of twenty-first century vertical and horizontal symbolic state-making: both as an instrumental means of enhancing the state's geopolitical power, as well as a means by which state is reified as environmentally sovereign and self-subsistent. So doing, the study complements a growing body of work in critical environmental geopolitics that has tended to eschew state-based analysis, or else leave the state underproblematized. As I argue, considering how the state is made natural, in turn helps to understand how nature is politically if not ontologically entangled in geopolitical thought and practice—in ways that attempts to act upon and indeed bring about wider-scale environmental subjects must contend.  相似文献   

20.
ABSTRACT

In the early 1970s, both the Canadian and United States federal governments introduced modern land claim agreements as a first step forward in the states’ recognition of Indigenous goals for self-determination. Since then, both the United States and Canadian federal governments have incrementally expanded their recognition of Indigenous rights to include Indigenous goals for political self-determination. Yet, despite the fact that both countries began implementing broadly similar policies at approximately the same time, the degree to which Indigenous political and economic self-determination has been realized varies considerably both within and between the two countries. The variation in Indigenous self-governing power and authority suggests that the policy shift towards Indigenous self-determination is incomplete and has faced important barriers to implementation. This paper investigates two key aspects of this variation in Indigenous self-determination in the United States and Canada: (1) institutional histories embedded in geography, and (2) the temporal nature of policy frameworks. I argue that the full realization of Indigenous self-determination has been shaped in different ways and, ultimately, is limited by the intersection of embedded institutional legacies and federal political dynamics.  相似文献   

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