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1.
Fuelwood is one of the major sources of energy in the domestic sector across the rural areas,especially in the developing regions across the world.The Northeastern Himalayan state of Manipur is dominated by the tribal population that largely depends on fuelwood from the nearby forest area.The entire dependence on forests for energy resources is affecting the sustainability of the forest ecosystem in the region,thus indicating the livelihood conditions.Since land-use land-cover change is the key driver to the change in resource availability of a region,the present study has tried to analyze the landcover changes over a period 28 years.The second major component affecting resource availability is the increasing population pressure that leads to changes in the land dynamics,which directly affect the resource production.Based on the existing consumption pattern,the total consumption of fuelwood in the watershed ranges fiom a minimum of 289.992 tons/year to a maximum of 3545.719 tons/year with an average of 1561.956 tons/year in the year 2009 and simulated fuelwood consumption for the year 2021 is around 1469.260 tons/year.Nine different probable scenarios of resource are proposed to calculate the stress value that can be used by the policy-makers and planners for suitable policy implementation at the micro level with a complex social system.  相似文献   

2.
Biomass,as fuelwood,is one of the major sources of energy in rural areas,especially in the mountainous regions of the world.As the increasing human population exerts more pressure on the forest thereby inducing an adverse effect on the sustainability of the ecosystem,which consequently causes fuelwood crisis at a local level,this crisis is spatio-temporal in nature.Thus,the major objective of this study is to assess the sustainability of fuelwood at different probable scenarios at a micro watershed level.The present study was conducted in the Phakot watershed,the Tehri Garhwal district of central Himalaya in India,during 2006-2008.Based on the vegetation composition in the study area,the net primary productivity(NPP)value of the Oak forest,and mixed oak and sal forests,was used for the quantification of fuelwood availability in evergreen and deciduous forests,respectively.The fuelwood demand was calculated on the basis of seasonal fuelwood consumption values.Nine probable permutations for availability-demand scenarios assuming the existence of high(H),low(L)and average(A)conditions were analyzed for evaluating the stress.The available annual harvestable fuelwood in the watershed is in the minimum and maximum ranges of 2283.28 to 4066.00 tons,respectively,per year whereas it has a demand of 110.76 tons as the minimum to 3659 tons as the maximum annually.This shows that in the current availabilitydemand scenario,the watershed does not have fuelwood crisis in the present situation but needs to maintain the sustainability of the system.Based on our study,it is concluded that,globally,more spatio-temporal study is required to understand the issues at the local level.  相似文献   

3.
Currently, energy consumption for cooking in rural households of India is mostly based on fuelwood used in traditional stoves. This paper presents results of a study carried out in a forest fringe area of India on cooking energy use. The concept of calculating levelized cost as cost per unit of useful energy is applied on source–device combinations of cooking and validated in Bargaon Community Development Block of Sundergarh District in Odisha, India. About 92 % of the households in the study area use fuelwood as the only energy source for cooking; the total use of fuelwood for only cooking, in the Block is nearly 1.8 times the total sustainable wood supply showing an urgent need for promoting alternative cooking energy options. This paper also presents an assessment of different cooking options in terms of cost per unit of useful cooking energy. LPG, biogas and gasifier stoves are found to be far too expensive for the local people. Briquette-fired improved stoves appear to be a promising cooking energy option in the study area. Government support and intervention are recommended for promoting this option.  相似文献   

4.
Land-use and land-cover changes have attracted substantial scientific interest in recent years because of their marked influence on hydrological cycles. In developed countries of the Mediterranean basin, the generalized revegetation and forest growth in mountainous areas that occurred during the last five decades are negatively affecting the evolution of water resources in headwaters. In this study, changes in land cover in the Duero River Basin (northern Spain) during the last 50 years were analyzed and their role in hydrological evolution was estimated. For this purpose, step-wise linear regressions were developed to estimate the evolution of runoff as a function of climate (precipitation and temperatures). The results show a significant expansion of forest cover in the headwaters, although it has been more extensive in the mountains to the north of the basin than to the south. River discharges in the headwaters underwent a generalized decline during the study period (1961–2006), but precipitation over the same period did not show an appreciable trend. In the absence of noticeable trends in removal of water for human consumption, our results indicate that revegetation is contributing to the observed hydrological decline. Our hypothesis is confirmed because of the greater divergence in the evolution of precipitation and runoff in the northern headwaters (more forest growth) than in the south headwaters (less forest growth). Results suggest that further increases in forest area will enhance hydrological decline and highlight the importance of integrating land-cover information in water availability assessments in a region where water is a strategic resource.  相似文献   

5.
There has been a concerted effort by the international scientific community to understand the multiple causes and patterns of land-cover change to support sustainable land management. Here, we examined biophysical suitability, and a novel integrated index of “Economic Pressure on Land” (EPL) to explain land cover in the year 2000, and estimated the likelihood of future land-cover change through 2050, including protected area effectiveness. Biophysical suitability and EPL explained almost half of the global pattern of land cover (R 2 = 0.45), increasing to almost two-thirds in areas where a long-term equilibrium is likely to have been reached (e.g. R 2 = 0.64 in Europe). We identify a high likelihood of future land-cover change in vast areas with relatively lower current and past deforestation (e.g. the Congo Basin). Further, we simulated emissions arising from a “business as usual” and two reducing emissions from deforestation and forest degradation (REDD) scenarios by incorporating data on biomass carbon. As our model incorporates all biome types, it highlights a crucial aspect of the ongoing REDD + debate: if restricted to forests, “cross-biome leakage” would severely reduce REDD + effectiveness for climate change mitigation. If forests were protected from deforestation yet without measures to tackle the drivers of land-cover change, REDD + would only reduce 30 % of total emissions from land-cover change. Fifty-five percent of emissions reductions from forests would be compensated by increased emissions in other biomes. These results suggest that, although REDD + remains a very promising mitigation tool, implementation of complementary measures to reduce land demand is necessary to prevent this leakage.  相似文献   

6.
Patterns of land-use and land-cover change are usually grouped into one of two categories defined by the dominant trend: (1) deforestation resulting from expanding agriculture and (2) forest expansion, usually related to the abandonment of marginal lands. At regional scale, however, both processes can occur simultaneously even in the absence of net change. Given the focus on net change, such redistribution of agricultural and natural and seminatural lands has been generally overlooked. The interaction between agriculture modernization, human demography and complex topographic gradients of northwestern Argentina has resulted in processes of both forest recovery and deforestation, thus providing the opportunity to analyze patterns and driving forces of land-cover redistribution. We analyzed 20 years (1986–2006) of land-cover change in a subtropical watershed in relation to topographic and demographic variables. Although net forest change represented <1 %, forests redistribution affected 7 % of forest lands. There was a consistent geographic segregation of deforestation and forest recovery, with forests expanding over steep highlands and agriculture expanding over lowland irrigated areas. Population trends were not associated to forest expansion in lowlands but they explained 32 % of forest recovery in highlands. Highland forest expansion and lowland deforestation, respectively, imply conservation opportunities for humid montane forests and the environmental services they provide (e.g., watershed conservation) and threats for the conservation of dry forests and its biodiversity. Our study exemplifies the importance of land-use redistribution (rather than net change) with relevant environmental consequences at regional scale.  相似文献   

7.
Variation in climate, disturbance regime, and forest management strongly influence terrestrial carbon sources and sinks. Spatially distributed, process-based, carbon cycle simulation models provide a means to integrate information on these various influences to estimate carbon pools and flux over large domains. Here we apply the Biome-BGC model over the four-state Northwest US region for the interval from 1986 to 2010. Landsat data were used to characterize disturbances, and forest inventory data were used to parameterize the model. The overall disturbance rate on forest land across the region was 0.8 % year?1, with 49 % as harvests, 28 % as fire, and 23 % as pest/pathogen. Net ecosystem production (NEP) for the 2006–2010 interval on forestland was predominantly positive (a carbon sink) throughout the region, with maximum values in the Coast Range, intermediate values in the Cascade Mountains, and relatively low values in the Inland Rocky Mountain ecoregions. Localized negative NEPs were mostly associated with recent disturbances. There was large interannual variation in regional NEP, with notably low values across the region in 2003, which was also the warmest year in the interval. The recent (2006–2010) net ecosystem carbon balance (NECB) was positive for the region (14.4 TgC year?1). Despite a lower area-weighted mean NECB, public forestland contributed a larger proportion to the total NECB because of its larger area. Aggregated forest inventory data and inversion modeling are beginning to provide opportunities for evaluating model-simulated regional carbon stocks and fluxes.  相似文献   

8.
Thailand plays an important role in the international trade of food and agricultural products, which is in alignment with its national strategy of serving as the “kitchen of the world.” When looking at its agricultural promotion and export policies, the country only counts the value gains from exports while neglecting environmental externalities related to plantation practices. The purpose of this study was to perform a trade-off analysis between consumptive water, land, and fertilizer use together with the economic values of major crops for export and consumption in the country. The results show that to gain income from agricultural exports, the country has exploited various natural resources. The area used to harvest rice, sugarcane, cassava, and rubber adds up to approximately 15.3 million ha: 7.2 million ha of which is for domestic consumption and 8.1 ha for export. To produce Thailand’s agricultural exports, total water use is estimated to be 49.8–67.5 billion m3 per year (61–65 %), while the amount used to produce crops for domestic consumption is 26.5–43.7 billion m3 per year (35–39 %). Meanwhile, 1,056–1,826 thousand tons (54 %) of fertilizer was used on crops for domestic consumption, and 1,222–1,370 thousand tons (46 %) of fertilizer was used on export crops. The best crop choice for export in terms of its export value, land use, fertilizer use, and water consumption is rubber. The worst crop choices for export are rice and cassava. More sustainable agricultural practices are needed to effect improvements such as increased yields and reduced fertilizer and water use.  相似文献   

9.
Fuelwood is the only important source of energy in the mountainous region of the Garhwal Himalaya, India. Since the commercial source of energy is generally beyond the reach of ordinary people due to their poor socio-economic conditions and due to limited supply and lack of communication facilities for transport of LPG, the villages of the inner region of the Garhwal Himalaya depend on their fuel requirement from the forest. In the present study, two villages of the Nanda Devi Biosphere Reserve in Uttarakhand part of the Indian Himalaya i.e. Lata and Dunagiri located at 2,415 and 3,600 m altitudes, respectively, were selected for the study of socio-economic profile and vegetation and for estimation of per capita fuelwood consumption and the degree of disturbance. The study was conducted from 2002–2005. The population of these villages is migratory and belongs to the Bhotiya community, a scheduled tribe consisting of two subgroups known as Tolcha and Marchha. They grow traditional crops as well as cash crops. Important tree species used for fuelwood include Cedrus deodara, Pinus wallichiana, Cupressus torulosa, Taxus wallichiana, Acer indicum, Quercus dilatata and Viburnum cotinifolium. Maximum density among trees was shown by Pinus wallichiana (169.6 trees ha−1) in village Lata and by Cedrus deodara (89.6 trees ha−1) in village Dunagiri. The average per capita consumption of fuelwood in villages Lata and Dunagiri was 4.03 and 4.77 kg capita−1 day−1. Maximum number of trees (29 and 31% lopping for Lata and Dunagiri, respectively) belonged to disturbance class 1 (1–20% lopping) followed by the disturbance class 2 (20–40% lopping). Due to location of these villages in the buffer zone of the biosphere reserve, the fuelwood consumption may cause an adverse impact on the ecological status of this reserve, which urgently requires employing strategies for the conservation and management of this biosphere in terms of fuelwood sustainability e.g. regulation of livestock stock and grazing, using alternative sources of fuels, plantation of multipurpose trees and adoption of ecotourism.  相似文献   

10.
Materials stocked in infrastructure provide necessary personal and economic services, and are also closely linked with massive resource extraction, energy consumption and waste generation. To support policy deliberations toward regional harmony and sustainable development, this paper examines the temporal change during 1978–2008 and spatial patterns of ten types of materials stocked in four major infrastructures (residential buildings, roads, railways, and water pipelines) in 31 provinces in China, and diagnoses regional disparity and driving factors by Theil index and multivariable regression based on panel data. It was found that the total material stock has boomed to 42.5 billion tons in 2008, with its per capita level increased by nine times over that in 1978. Over 90 % of materials are concentrated in residential buildings and roads, and are spatially inclined to decrease from coastal regions to inland areas. Since China has shifted its strategy from an inclined to harmonious regional development, the overall inequality of per capita material stock has been changing toward equality with its scale contributed mainly by inter-regional inequality, and downward trend affected dominantly by intra-regional inequality. To balance the growth speed across regions meanwhile, to develop economy and attract foreign investment in each region, would be a promising route towards reducing regional inequality. Moreover, the enhancement of governmental performance and construction of each sector’s share would also be effective for decreasing inter-regional gaps.  相似文献   

11.
近年来,江苏省社会经济进入新的发展期,在经济高速发展的背后是能源的高消耗以及温室气体的大量排放。根据江苏省实际情况,运用LEAP模型建立了JSLEAP模型,并采用情景分析的方法,根据影响江苏省能源需求的因素设定了参照情景和可持续发展情景两个情景,系统地、全面地对江苏省未来能源需求和碳排放的发展趋势进行了分析,并提出了江苏省中长期能源发展对策,对江苏省制定正确的能源发展规划、实现可持续发展具有重要意义。研究表明:在两种情景下江苏省未来能源需求总量将持续增加,直到2045年后才有所下降;居民生活、第一产业、第二产业、第三产业各部门能源需求情况都将有所变化;人均CO2排放量、单位GDP的CO2排放量都将降低。但是无论是能源需求或碳排放方面,可持续发展情景都优于参照情景  相似文献   

12.
Extensive forests in Croatia represent an important biological and economic resource in Europe. They are characterised by heterogeneity in forest management practices dating back to the socialist planned economy of the pre-1991 era. In this study we investigated the difference in rates of deforestation and reforestation in private- and state-owned forests during the post-socialist period and the causal drivers of change. The selected region of Northern Croatia is characterised by a high percentage of privately owned forests with minimal national monitoring and control. We used a mixed-methods approach which combines remote sensing, statistical modelling and a household-based questionnaire survey to assess the rates of forest cover change and factors influencing those changes. The results show that predominantly privately owned forests in Northern Croatia have recorded a net forest loss of 1.8 % during the 1991–2011 period, while Croatia overall is characterised by a 10 % forest cover increase in predominantly state-owned forests. Main factors influencing forest cover changes in private forests are slope, altitude, education structure, population age and population density. The results also show that the deforestation in private forests is weakening overall, mostly due to the continuation of the de-agrarisation and de-ruralisation processes which began during socialism.  相似文献   

13.
Lantana camara. L (hereafter Lantana) was first introduced by the British into India in 1807 as an ornamental plant. Since then the species has spread across the length and breadth of the country. Attempts to control Lantana in India have not been successful. In this study, we analysed the use of Lantana by local communities in southern India and identified the possible causes and consequences of its use through the use of a household survey of the socio-economic profile of the user and nonuser households and an analysis of the ecological history of the communities. Communities have been using Lantana for over 25–30 years and apparently such use was not prompted by external agencies. The characteristics of user and nonuser households were similar, except that Lantana users were more literate and had a greater number of occupations per household than nonusers. Per capita income was similar between user and nonuser groups. For nonuser groups, their main income sources were from trading (44 %), wage labour (32 %) and forest resources (23 %). In contrast, the Lantana user groups substituted their loss of income from forest resources (7 %) by income from Lantana (46 %). The ecological history revealed that Lantana was adopted as a resource at a time when it was increasing in the landscape and traditional bamboo resources were in decline because of overuse by commercial enterprises and mast flowering. This change in ecological resource availability prompted a major shift in livelihoods for some in the area.  相似文献   

14.
This study aimed to assess Japan’s recent “local production for local consumption” (LPLC) movement, with a special focus on vegetables in the Osaka city region of central Japan. After collecting statistics and spatial data, we conducted a multi-scale analysis of vegetable production and consumption along with the associated energy consumption, using geographical information system software at three spatial scales along the vegetable flow paths: national, regional, and local. Vegetables consumed in the Osaka city region came from prefectures throughout Japan, and we mapped the foodshed within this region at 1-km spatial resolution, as well as the distribution of farmland, farmers’ and other markets. We also conducted a scenario analysis for reduced energy consumption through organic farming and the utilization of abandoned farmland near a city to replace food imports from distant areas. We found that the large majority of vegetables consumed in the Osaka city region currently come from remote prefectures, and that this is associated with a high level of energy consumption. Inside the Osaka city region, peri-urban vegetable farming contributes to regional vegetable provision, resulting in an approximately 70 % production/consumption ratio within an 80-km radius of the urban center; if all of the area of abandoned farmland were restored to production, this ratio would increase to approximately 75 %. Organic farming activities that bring together farmers and urbanites are emerging in many parts of the study area, contributing to increased LPLC. Scenario analysis suggested that a decrease of more than 1 × 106 GJ of energy inputs could be achieved through wider adoption of local organic farming for local consumption and complete utilization of abandoned farmland in the Osaka city region.  相似文献   

15.
Global tropical deforestation continues to occur at high rates despite political attention. National-level forest baselines are being established all over the world to guide the implementation of several policy mechanisms. However, identifying the direct and indirect drivers of deforestation and understanding the complexity of their interlinkages are often difficult. We first analyzed deforestation between 1990 and 2005 at the national level and found an annual deforestation rate of 0.62 %. Next, we performed separate analyses for four natural regions in Colombia and found annual deforestation rates between 0.42 and 1.92 %. Using general linear models, we identified several direct causes and underlying factors influencing deforestation at the national level: rural population density, cattle, protected areas, and slope. Significant differences in deforestation rates and causes were found across regions. In the Caribbean region, drivers of loss are urban population, unsatisfied basic needs, slope, and precipitation and four land use variables (illicit crops, pastures, cattle, and fires). In the Orinoco region, crops are the main driver of forest loss, and in the Amazonian region, deforestation is primarily due to fires related to the colonization front. Policy mechanisms will have to take into account regional patterns to successfully balance development and forest preservation in Colombia.  相似文献   

16.
Land-cover change is the result of complex multi-scale interactions between socioeconomic, demographic, and environmental factors. Demographic change, in particular, is thought to be a major driver of forest change. Most studies have evaluated these interactions at the regional or the national level, but few studies have evaluated these dynamics across multiple spatial scales within a country. In this study, we evaluated the effect of demographic, environmental, and socioeconomic variables on land-cover change between 2001 and 2010 for all Mexican municipalities (n?=?2,443) as well as by biome (n?=?4). We used a land-cover classification based on 250-m MODIS data to examine the change in cover classes (i.e., woody, mixed woody, and agriculture/herbaceous vegetation). We evaluated the trends of land-cover change and identified the major factors correlated with woody vegetation change in Mexico. At the national scale, the variation in woody vegetation was best explained by environmental variables, particularly precipitation; municipalities where woody cover increased tended to be in areas with low average annual precipitation (i.e., desert and dry forest biomes). Demographic variables did not contribute much to the model at the national scale. Elevation, temperature, and population density explained the change in woody cover when municipalities were grouped by biome (i.e., moist forest, dry forest, coniferous forest, and deserts). Land-cover change at the biome level showed two main trends: (1) the tropical moist biome lost woody vegetation to agriculture and herbaceous vegetation, and (2) the desert biome increased in woody vegetation within more open-canopy shrublands.  相似文献   

17.
Small island developing states (SIDS) face multiple threats from anthropogenic climate change, including potential changes in freshwater resource availability. Due to a mismatch in spatial scale between SIDS landforms and the horizontal resolution of global climate models (GCMs), SIDS are mostly unaccounted for in GCMs that are used to make future projections of global climate change and its regional impacts. Specific approaches are required to address this gap between broad-scale model projections and regional, policy-relevant outcomes. Here, we apply a recently developed methodology that circumvents the GCM limitation of coarse resolution in order to project future changes in aridity on small islands. These climate projections are combined with independent population projections associated with shared socioeconomic pathways (SSPs) to evaluate overall changes in freshwater stress in SIDS at warming levels of 1.5 and 2 °C above pre-industrial levels. While we find that future population growth will dominate changes in projected freshwater stress especially toward the end of the century, projected changes in aridity are found to compound freshwater stress for the vast majority of SIDS. For several SIDS, particularly across the Caribbean region, a substantial fraction (~?25%) of the large overall freshwater stress projected under 2 °C at 2030 can be avoided by limiting global warming to 1.5 °C. Our findings add to a growing body of literature on the difference in climate impacts between 1.5 and 2 °C and underscore the need for regionally specific analysis.  相似文献   

18.
To assess the impact of land-use change on carbon stocks, we apply a new methodology, linking ecological and economic modeling, to southern Yucatan, Mexico. A spatial econometric multinomial logit model of ten land-cover classes is estimated (four primary forest categories, three secondary growth categories, an invasive species, and two agricultural land-cover categories), using satellite data on land cover, linked with census socioeconomic data and other biophysical spatial data from 2000. The analysis is novel in that it is the first attempt to link detailed satellite data on land use, with on-the-ground estimates of carbon stocks in a spatial econometric model of land use. The estimated multinomial logit model is then used with two scenarios of future economic growth (“low growth” and “high growth” changes in population, agricultural land use, market access, and education levels) in the region to predict land-cover changes resulting from the economic growth. The per hectare carbon (C) stocks in each land-cover class are derived from previously published estimates of biomass from field sampling across the study region. We consider aboveground-only, aboveground plus soil, transient and non-transient pools of carbon. These estimates are scaled up to the total area in each class according to the predictions of the model baseline and the two development scenarios. Subsequently, the changes in carbon stocks resulting from the predicted land-cover changes are calculated. Under the low growth scenario, carbon stocks declined by 5%; under the high growth scenario, losses were 12%. Including soil C, the proportional losses were lower, but the absolute amount lost was more than double (to 6 Tg C under the low and almost 15 Tg C under the high-growth scenario). This methodology could be further developed for applications in global change policy, such as payments for environmental services (PES) or reduction in emissions from deforestation and degradation (REDD).  相似文献   

19.
District Swat is part of the high mountain Hindu-Kush Himalayan region of Pakistan. Documentation and analysis of land use change in this region is challenging due to very disparate accounts of the state of forest resources and limited accessible data. Such analysis is, however, important due to concerns over the degradation of forest land leading to deterioration of the protection of water catchments and exposure of highly erodible soils. Furthermore, the area is identified as hotspot for biodiversity loss. The aim of this paper is to identify geophysical and geographical factors related to land use change and model how these relationships vary across the district. For three selected zones across the elevation gradient of the district, we analyse land use change by studying land use maps for the years 1968, 1990 and 2007. In the high-altitude zone, the forest area decreased by 30.5 %, a third of which was caused by agricultural expansion. In the mid-elevation zone, agriculture expanded by 70.3 % and forests decreased by 49.7 %. In the lower altitudes, agriculture expansion was 129.9 % consuming 31.7 % of the forest area over the forty-year time period. Annual deforestation rates observed were 0.80, 1.28 and 1.86 % in high, mid and low altitudes, respectively. In the high-altitude ecosystems, accessibility (distance to nearest road and city) had no significant role in agriculture expansion; rather land use change appears significantly related to geophysical factors such as slope, aspect and altitude. In the low-elevation zone, accessibility was the factor showing the closest association with agriculture expansion and abandonment. The analysis illustrates that land use change processes vary quite considerably between different altitudinal and vegetation cover zones of the same district and that environmental constraints and stage of economic development provide important contextual information.  相似文献   

20.
The paper describes the results of a study of the impact of the National Energy on the trend towards increased utilization of coal and lignite in Texas with forecasts of increased coal and lignite utilization for the electric utility and industrial sectors. Environmental impacts of this increased coal and lignite use are projected in terms of increased air pollutant emissions and air quality impacts. Economic costs of compliance with alternative source emission regulations are also projected for the electric utility industry.Lignite consumption in Texas under the National Energy Plan is projected to increase from the present 13 million metric tons in 1976 to 57 million metric tons annually by 1985. Sub-bituminous coal consumption in Texas is projected to increase from 1 million metric per year in 1976 to 49 million metric tons per year in 1985. Bituminous coal consumption in Texas is expected to increase from less than one million metric tons per year in 1976 to about 3 million metric tons per year in 1985.Major increases in sulfur oxides emissions from coal and lignite combustion in Texas can be expected by 1985 of up to 1.5 × 109 kg per year without controls and 0.2 × 109 kg per year with controls. Increases in acid precipitation formation will result in north-east Texas from extensive lignite usage for electric power generation as a detriment to agriculture. The photochemical air pollution problem in the Houston area will probably worsen primarily because of increased nitrogen oxides and sulfur oxides emissions because of industrial coal combustion. Capital costs of air pollution controls in Texas for coal-fired utility boilers are estimated as up to U.S. $3.9 billion by 1985, with total operating costs of up to U.S. $1.2 billion per year.  相似文献   

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