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1.
The study takes a conventional supply and demand approach to the study of fuelwood use. It compares estimated wood production in West African bush and forest formations based on an available equation using rainfall data with own collected data on local wood consumption in a village in southern Mali. To allow comparison, data from 49 other villages in the same area are analysed. This study, toget her with an earlier study in northern Mali, indicates that locally induced deforestation caused by fuelwood use does not represent an immediate problem in rural Mali. Local use of fuelwood does not seem to be exceeding forest regeneration. However, where there is external pressure on the forest represented by commercial exploitation of wood for sale in the urban centres, fuelwood depletion might occur.  相似文献   

2.
The role of forest ecosystems in the regulation of greenhouse effect at the global scale is developed here, from two points of view, sometimes considered as opposed: carbon storage and wood production for energy. A nomenclature is proposed to understand all the various mechanisms implied in carbon storage. A comparison is made between the effects on carbon emissions of storage alone and storage with wood fuel production. Use of wood energy is proved to be a ‘bonus’ that could optimise, in the middle and long terms, the use of fossil fuel reserves. To cite this article: A. Prieur et al., C. R. Geoscience 336 (2004).  相似文献   

3.
The islands of Tiree and Coll in the Scottish Inner Hebrides are dominated by staircases of glaciated rock-platform surfaces in Lewisian gneiss that are interpreted here as areas of strandflat. The rock platform surfaces exhibit differential glacio-isostatic uplift from east to west and are considered to indicate at least four separate periods of strandflat formation during prolonged intervals of Quaternary cold climate. It is suggested that many of the well-known areas of high rock platform located farther east in the Scottish Inner Hebrides represent eroded remnants of the strandflat surfaces described here. The existence of the Tiree and Coll strandflat surfaces in conjunction with their formation during periods of Quaternary glaciation implies that they were produced during periods when mainland Scotland was ice-covered yet when the western margin of the ice sheet was normally located east of these islands. A prominent Late-glacial raised shoreline also occurs on both islands and declines in altitude to the west, from 22 m in northeastern Coll to 9 m in western Tiree. It is believed that this shoreline, whose regional gradient is 0.39 m km?1, may represent part of the Main Wester Ross Shoreline that was formed in the Northwest Highlands of Scotland during a period of glacial advance that interrupted the decay of the last (Late Devensian) ice sheet. The general similarity in altitude between the Late-glacial shoreline features and rock platform surfaces implies that during each period of Quaternary strandflat formation, relative sea-level returned to the same approximate position. This would appear to indicate that the glacio-isostatic and glacio-eustatic components affecting the positions of relative sea level in Scotland have remained in approximate equilibrium throughout the duration of the Quaternary.  相似文献   

4.
Training and Guidance (TAG) units in the Scottish Highlands are sites that people with mental health problems can access for training and learning activities designed to prepare them for (re-)entry into the labour market. These units also perform other, perhaps more intangible, roles in assisting trainees to cope with their mental health problems, thereby offering a supportive setting with therapeutic dimensions (albeit one not explicitly configured as delivering therapy). In this paper we explore the ‘in-between’ quality of the TAG units as spaces that might be said to possess dual economic and social roles. Using primarily qualitative evidence, we investigate both sets of roles, debating the extent to which the economic and social imperatives complement or contradict one another. The paper contributes to critical commentary on how ‘workfare’ initiatives articulate with the experiences and concerns of disabled trainees, the novelty arising in part from centralising the material spaces at the heart of such initiatives.  相似文献   

5.
Information on emissions from restaurant industry is limited in scientific literature. Emission inventory of greenhouse and non-greenhouse air pollutants from restaurant industry was prepared for two Class 1 Indian cities, viz. Nagpur and Raipur for 2010. Emissions were estimated from a primary database on type and amount of cooking fuel combusted in restaurant industry in the selected cities. Liquefied petroleum gas, charcoal, wood, coal, diesel and candy coal are used in this industry, first three being the major ones. Carbon dioxide emission was highest in both cities and liquefied petroleum gas, charcoal and wood were the major contributors to emissions. Total annual emissions of greenhouse gases, viz. carbon dioxide, methane and nitrous oxide were estimated to be 19,251, 27 and 1 Mg year?1 in Nagpur and 21,207, 34 and 1 Mg year?1 in Raipur, whereas total annual emissions of non-methane hydrocarbon (NMHC), carbon monoxide, total suspended particulate (TSP), sulphur dioxide, nitrogen oxides and black carbon (BC) were 96, 959, 31, 12, 19, 3 Mg year?1 and 87, 1141, 78, 37, 28, 6 Mg year?1 in Nagpur and Raipur, respectively, from all the fuels used in restaurant industry. Considering the huge growth of Indian restaurant industry in the last decade and the predicted growth in future, emissions from this industry is assumed to grow and will play a major role in governing regional and national emissions in India.  相似文献   

6.
《Atmósfera》2014,27(1):61-76
The Carbon Tracker system will play a major role in understanding CO2 sinks and sources, gas exchange between the atmosphere and oceans, and gas emissions from forest fres and fossil fuels in Latin America and the Caribbean. This paper discusses the trends in carbon fluxes in the biosphere and ocean, as well as emissions from forest fres and fossil fuel use in the above-mentioned region, using the Carbon Tracker (CT) system. From 2000 to 2009, the mean carbon fluxes for the biosphere, fossil fuel use, wildfires and the ocean in Latin America and the Caribbean were −0.03, 0.41, 0.296, −0.061 Pg C/yr, respectively, and −0.02, 0.117, 0.013, −0.003 Pg C/yr, respectively, in Mexico. The mean net carbon flux for Latin America and the Caribbean was 0.645 Pg C/yr, and 0.126 Pg C/yr for Mexico. The terrestrial sinks in Latin America and the Caribbean are dominated by the forest, agricultural, grass and shrub regions, as well as the Andes mountain range and the net surface-atmosphere fluxes including fossil fuel are dominant in regions around large cities in Mexico, Brazil, Chile, and areas undergoing deforestation along the Amazon River. The results confirm that forest fres are an important source of CO2 in Latin America and the Caribbean. In addition, we can confirm that policies encouraging the use of ethanol in light vehicles in Brazil have helped to decrease carbon emissions from fossil fuel, and assume the effects of the Proárbol program on carbon sinks from the biosphere and from fire emissions sources in Mexico. Based on this analysis, we are confident that the CT system will play a major role in Latin America and the Caribbean as a scientific tool to understand the uptake and release of CO2 from terrestrial ecosystems, fossil fuel use and the oceans, and for long-term monitoring of atmospheric CO2 concentrations.  相似文献   

7.
The last Scottish ice-sheet: facts and speculative discussion   总被引:1,自引:0,他引:1  
Evidence relating to the extent of the last (Late Devensian) Scottish ice-sheet is critically discussed, particular attention being given to the limitations of some radiocarbon dates and incorrect inferences based on radiocarbon dates. It is suggested that the last Scottish and Scandinavian ice-sheets were not confluent and that Orkney and NE Caithness may not have been covered by the last Scottish ice-sheet. Ice-sheet growth and decay are considered in relation to possible positions of the oceanic and atmospheric polar fronts: implications are that much the greater part of ice-sheet decay resulted from inadequate snowfall and that the maximal limits of the last ice-sheet may not have been synchronous. Ice-sheet calving may have resulted in an independent ice mass over the Outer Hebrides. It is suggested that most of the bed of the Central North Sea became land during the Late Devensian and that a large delta existed in the eastern part of this area. It is also suggested that the buried and infilled channels of this eastern area, which are normally interpreted as tunnel valleys, are shallow delta channels whose present depth is due to delta subsidence  相似文献   

8.
This article reviews the wood fuels situation in the Sahel and the findings of various needs assessment methodologies, especially as these are relevant to the numerous programmes to introduce improved cooking technologies in the region. Most people in West Africa, especially in poor and rural areas, rely primarily on wood fuels and crop wastes for energy needs, with devastating environmental consequences. Most wood is used in cooking. The quantity of fuel used depends on the type of fireplace, utensils used, how and when food is prepared, food preparation methods, types of fuels, how fuelwood is collected, and special customs surrounding the family fire — all of which are intimately associated with the economic, cultural and social fabric of Sahelian societies. Conventional fuel consumption and resource surveys have yielded useful information about quantitative energy needs in the Sahel, but increasingly sociocultural studies are being used to ensure that stove designs will meet the needs of the end-user. Economic analssis is also necessary to establish the dimensions of wood scarcity, to assess the financial attractiveness to consumers of alternative fuels and stoves, and in evaluating the costs and benefits to society of proposed national woodstoves programmes.  相似文献   

9.
It is argued that high-level shell beds buried by till at various localities around the Scottish coast are in situ and represent a marine transgression immediately prior to and consequent upon loading of the earth's crust by the build-up of the last Scottish ice sheet. The high-level rock platforms of the Hebrides may also have been eroded at this time. A relationship between the build-up of the last Scottish ice sheet and world sea-level is suggested and it is further argued that the Scottish ice sheet was a more sensitive indicator of the onset (and termination) of a period of northern hemispheric glaciation than either the Laurentide or Scandinavian ice sheets. It is suggested that the build-up of the last Scottish ice sheet took place in the Early Devensian and a tentative correlation is proposed between the Scottish evidence and the deep-sea evidence for glacier build-up at ca. 75,000 years B.P  相似文献   

10.
Khan  Irum  Saqib  Muhammad  Hafidi  Houda 《GeoJournal》2021,86(2):663-677

The study examines the relationship between poverty and forest cover degradation in rural areas of Pakistan. The area selected for the study District Upper Dir is a rural and relatively backward region located in northwestern Pakistan, in Khyber-Pakhtunkhwa province. The study area is undergoing severe deforestation and natural disasters in the recent past. The study consists of two stages, in first stage the traditional Geographical information system image was used to analyze the spatial–temporal situation of the surroundings. In the second stage, well-designed questionnaire was used to collect the primary information from 420 randomly selected households of research areas. A multidimensional poverty index has been used to measure the poverty profile of the population. It has been found that 55% households were below the poverty line. Almost, 95% households are using wood for cooking purposes. High dependence on natural resources causes forest cover degradation while burning off too much wood causes CO2 emission and leads to environmental degradation. A major portion of population is living on steeply sloped areas with certain risks. It is found that frequency of flash flood is 53% and agricultural land (54%) is at high risk and often flows with flash floods. It is concluded that there is strong correlation between multidimensional poverty and forest cover degradation which leads to climate and environmental risks.

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11.
Scottish Dinantian transitional to mildly alkaline volcanism is represented by abundant outcrops in the Midland Valley, Southern Uplands and Highlands provinces. Dinantian volcanic rocks from Kintyre in the Scottish Highlands range in composition from basalt through basaltic hawaiite, hawaiite, mugearite and benmoreite to trachyte, the compositions of the evolved types being largely due to differentiation from the basaltic parents.Recent geochemical investigations of Scottish Caledonian granitoids, Siluro-Devonian Old Red Sandstone (ORS) lavas and xenolith suites from numerous vents and dykes of Permo-Carboniferous to Tertiary age have revealed that the Scottish crust and upper mantle both increase in age and are increasingly enriched in incompatible elements towards the north and northwest. The upper mantle and lower crust below the Highlands province are therefore largely considered to be more enriched and in parts older than those below the Midland Valley and Southern Uplands. Dinantian alkali basalts from these latter two provinces have Nd values predominantly in the range +3 to +6, initial 87Sr/86Sr values of 0.7029–0.7041 and 207Pb/ 204Pb values of 15.48–15.60. However, similar basalts from Kintyre and Arran in the Highlands have lower Nd (+0.1 to +3.4) and 207Pb/204Pb (for given 206Pb/204Pb ratios; 15.49–15.51) and slightly higher 87Sr/86Sr (0.7033–0.7046). This regional variation correlates well with the differences seen between Midland Valley and Highland magmas in the ORS calc-alkaline suite (Thirlwall 1986) and it is suggested that both the ORS and Dinantian basic rocks are derived from similar types of mantle, although no lithospheric slab component is present in the later Dinantian suites. Isotopically-distinct portions of mantle therefore appear to have been present below the Highland and Midland Valley-Southern Upland provinces from at least Caledonian to Carboniferous times. The combined incompatible element and Sr-Nd-Pd isotopic evidence from Kintyre and Arran basaltic rocks does not allow unequivocal distinction between a lithospheric mantle and a sublithospheric mantle source. The observed correlation between isotopic composition of Dinantian basalts and the chemical composition of the lithosphere, together with the apparent involvement of long-term separated source reservoirs suggests that Kintyre and Arran lavas were derived largely from a lithospheric mantle source. On the other hand, the isotopic enrichment of Kintyre basaltic rocks is not extreme; trace element and isotopic compositions are still comparable to modem OIB. Sublithospheric mantle could therefore also be a viable source for Kintyre and Arran Dinantian volcanism.  相似文献   

12.
Until recently orthodoxies on fuelwood and desertification have formed the cornerstones of mainstream views in research and development related to natural resources in the Sahel. Based on an empirical study of the fuelwood situation in the Gourma region in Mali, this article throws a critical light on these viewpoints. There is no relationship between deforestation and domestic fuelwood consumption in the Gourma. The fuelwood used comes from dry wood collected from dead trees. Collection distances are, however, getting longer; so people need to use more time for the collection of wood, or more of their limited incomes have to be spent on buying fuelwood. Therefore, the fuelwood problem in the Gourma is of a social and economic rather than an ecological character. Sahel orthodoxies, which are manifested in the national Malian plan to fight desertification, are used by the Water and Forests Service to justify their policy of harassment towards the rural poor. These orthodox beliefs about environmental issues in drylands are generalizations which tend to gloss over important regional diversities. The data presented should therefore not be used to create new orthodoxies. They should rather be regarded as a warning not to use generalizations on local realities about which there is no reliable information.  相似文献   

13.
Conclusion There is no doubt that Northern Ireland's lignite deposits are of high quality and constitute a natural resource of considerable potential value in this small, peripheral part of the European Community. Whether or not one or more will be used commercially and, if so, when depends on an interacting complex of economic, social and political factors. In purely economic terms, use will be effectively determined by lignite's economic competitiveness as a fuel dor electricity generation and on the relationship between capital and fuel costs. The economics of other possibly viable products such as lignite briquettes will be heavily dependent on the use of by-products of electricity generation, most notably surplus heat.The availability of lignite offers an alternative fuel option to those charged with formulating the Province's energy policy. If, as now seems likely, it is no longer a serious competitor for the power station planned for the mid-1990's, it most certainly is a competitor for the early part of the next century. This is particularly so in view of its low sulphur content which is about half that of Scottish coal on an energy equivalent basis. Lignite also offers security of supply at predictable prices, an important advantage, and thus carries a premium over coal, oil and natural gas which are imported at prices determined wholly exogenously.As the Province has by far the highest rate of regional unemployment in the United Kingdom, one argument advanced for the use of indigenous lignite is that its use in electricity generation would create much needed additional employment — an estimated 400 jobs being associated with the mining operations needed to support a 450 MW power station. But the Coagh example shows that other considerations must be taken seriously. It is extremely unlikely that the lignite in this area will ever be worked unless local attitudes change dramatically or there is some national fuel crisis which would over-ride local opposition. It is difficult enough developing lignite without having to contend with such strong resistance at the local level.This study has shown that certainly in the Northern Irish context it is highly important for the policy makers not only to consider the economic factors involved in choice of an energy fuel but to work closely with local communities and the various environmental bodies, to take their perceptions, right or wrong, into consideration.  相似文献   

14.
The aim of the paper is to examine wood as a source of fuel energy in rural South Africa and factors influencing its usage. The analysis is based on household profiles and characteristics (e.g., gender, caste, population and income) in a livelihood framework. Fuelwood consumption was estimated to be 692 kg/capita, and 4343 kg/user household per annum, valued at $311 per household. Consumption was modelled in relation to informal and formal cash incomes, and population of children, female and male adults. However, only the population of female adults could significantly influence consumption of fuelwood. This implied that where there were more women in a household, consumption was likely to be high. This might be due to the majority of women doing the cooking and heating in the household. Any change in the value of cash income of households had no significant impacts on fuelwood consumed. Cash incomes might therefore not be strong determinants of the types of energy used by rural households. The average quantity of wood consumed for fuel energy in summer was not significantly different from consumption in winter. Some households perpetually used more wood than others. The study further showed that harvesting of wood for fuel energy is not opportunistic, but requires reallocation of time for other livelihood activities in times of shortage. The fuelwood crisis is not simple and not only about shortage of fuelwood and/or population growth but linked to household profiles and other livelihood strategies and subsequently vulnerability of households. These would require thorough investigation and understanding in relation to precise demand and supply data for fuelwood before the fuelwood problem can be sufficiently managed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

15.
Blue-green hornblendes are observed in metabasite assemblages throughout the chlorite, biotite and garnet zones of the southwest Scottish Highlands. Actinolites are common in more Mg-rich metabasites in these zones. At low grade, hornblendes are relatively edenite-rich, and may sometimes occur together with a more Mg-rich, Al-poor actinolite. Within the garnet zone, hornblendes are pargasitic, showing extensive tschermakite substitution. Textural and chemical evidence do not indicate the presence of any miscibility gap between hornblende and actinolite within the chlorite to garnet zones in the southwest Highlands. The occurrence of hornblende-actinolite pairs in metabasites of the Scottish Dalradian, and perhaps also in other metamorphic terrains, is considered to reflect the incomplete chemical equilibration of lower grade actinolitic amphibole during prograde metamorphism, rather than a miscibility gap. The paucity of amphibole compositions intermediate between hornblende and actinolite in many metamorphic terrains is thought to reflect the rapid but continuous change of stable amphibole compositions in metabasites over a small range of increased metamorphic grade.  相似文献   

16.
Grenzebach K 《GeoJournal》1978,2(3):215-224
The spatial analysis of agricultural development is the necessary precondition for research in the rural landscape and for rural planning. Basic data emerging from field investigation and a systematic interpretation of aerial photographs have resulted in a series of thematic maps of Southern Nigeria and parts of Western Cameroon. This comprehensive research work has been organized within the framework of the Afrika-Kartenwerk of the German Research Society.In this paper our recently published population map of the scale of 1:1 million and the map of rural settlement patterns form the basis for some rather general estimates of agricultural potential. Exact spatial information of simple but non the less most important regional processes, like migration, are caused by population pressure. Not bare statistical figures but their transformation by cartographic means forms a fundament for area studies and hypothetical prospects for regional planning as well as for regional analysis.By larger scale observations agricultural carrying capacity, evaluation of rural potential, migration dynamics and changes of land-use systems have to be analyzed. This calls for meticulous studies of individual areas. The first of three such case studies stresses the process of intensification of land utilization near the Nsukka-Escarpment. Linear settlement patterns and chains of regular individually owned stripfields can be seen as inprints of a dynamic transformation within the cultural landscape. Reception of new agricultural technology has been a way for emigrant farmers to exploit traditionally sparsely utilized zones with rich soils, which had been less attractive, because they were hard to cultivate with the hoe.The second case deals with the well known migratory and agro-economic links between the overpopulated food crop belt of Northern Yoruba Savannah Country and the cocoabelt in the rain forest about 100 km further south.In Central Iboland rural overpopulation of more than 1000 persons per km2 and land shortage theoretically could be diminished by opening up uninhabited areas of the Niger flood-plain and the delta for modern agricultural exploitation. But not only the physical obstacles such as there are poor soils, very high rainfall and seasonal floods within the Niger low lands are hindering rural colonization. Social and political factors, like ethnic traditions and historic barriers still seem to be very perserverant. All this hardly allows strangers to get hold of unused land, to exploit valuable natural resources or to introduce modern agricultural technology. But generally speaking, population pressure as well as higher demand for social services and better incomes result in changes in the traditional land-use systems. The impact of growing urban or industrial economic spheres on agriculture acts as accelerating factor in this development. A paradise-landscape for Africa where optimal utilization of all physical resources under best socio-economic conditions may be practiced and where more than ten times of the present population of Africa could exist, as CAROL puts it in one of his scenarios (1973 and 1975), seems to be quite unrealistic and really never will be desirable.  相似文献   

17.
A pellet-filled boring in fossil wood is described from the Early Cretaceous Wessex Formation (Barremian), Isle of Wight. The cylindrical boring, approximately 1 cm in diameter, is filled with carbonaceous pellets with a hexagonal shape, preserved within a matrix of pyrite. Features of the boring suggest that it was made by termites that bored into the wood, either when the tree was alive or in the early stages of decay on the forest floor. This evidence of termite activity complements previous records of termite wing fossils and faecal pellets in Wealden sediments and is evidence for social behaviour in Wealden insects. This is one of the oldest records of termite borings in wood.  相似文献   

18.
Recognition of the limits to fossil fuel reserves and dramatic increases in the prices of many conventional fuel sources have promoted an interest in renewable energy resources. Biomass from forest plantations is recognized as one alternative with potential in many countries. This paper describes the general characteristics of forest energy plantations. The results of an extensive survey of forest energy development projects throughout the world are presented, therein providing an international perspective on the status of energy plantations. The potential contribution of forest energy projects in the developing nations is examined in greater detail.  相似文献   

19.
C Sivaprakash 《Lithos》1981,14(1):29-33
From the observed textures and mineral associations, chemographic relations have been derived in isobaric T-XCO2 space for the minerals actinolite, ankerite, calcite, chlorine, epidote, and hornblende in Scottish Dalradian metabasites from Central Perthshire. Mineralogical variations in the carbonate-bearing metabasites within the distances of 0.5-1 km or so, are attributed to varying partial pressures of CO2 operating during metamorphism.  相似文献   

20.
Christopher A. Thoms   《Geoforum》2008,39(3):1452-1465
Community forestry in Nepal vests rights of access, use, exclusion, and management of national forestland to local user groups. There is strong potential for community forests to serve as the basis for improving the quality of life and the status of livelihoods in rural Nepal while conserving forest resources. Frequently, community forest user groups are dominated by local elites who choose to close access to community forestland for several years. As a result, forest conditions are improving, but the poorest households bear the cost of strict protection. In this paper I argue that community forestry is thus having rather limited success at improving rural livelihoods. Although community forestry is fairly successful at conservation, there remain huge wealth disparities between community forest member households, limited access to vital forest products, and significant power disparities within community forest user groups. Such conditions of inequity, reinforced by current community forestry policy and practice, severely challenge the development potential of community-controlled natural resources. In Nepal, overcoming these challenges may require a change in policy that mandates more inclusive local decision-making.  相似文献   

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