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101.
研究以能源消费模式为切入点,分析中原经济区能源消费总量、消费结构和利用效率的现状水平,并分析能源消费引起的大气环境压力状况。基于经济发展速度调控及节能减排力度的不同,设置2020年三种能源消费情景,使用区域能源消费总量优化模型模拟预测不同情景下的能源消费总量,并分析不同情景下的大气环境压力。结果表明,快速发展和适度发展Ⅰ情景下,2020年区域能源消费总量将比2012年增加4.2×10~8tce和2.4×10~8tce,煤炭消费总量将增加3.1×10~8tce和1.2×10~8tce,大气污染物排放压力增加30%和50%;适度发展Ⅱ情景下,能源消费总量将增加0.2×10~8tce,煤炭消费总量将下降0.3×10~8tce,大气污染物排放压力将降低20%。因此,要实现经济发展稳步增长(年均增长率7.7%)和大气污染物排放总量削减10%目标,重中之重是实现煤炭消费总量\"零增长\"或\"负增长\",同时力争能源消费总量控制在5×10~8~6×10~8tce,凭借煤炭占比大幅下降(降至65%左右)最大限度发挥能源供给领域节能效应,依靠产业结构升级节能效应和技术节能拓展能源消费领域节能空间,将能效水平提高至0.6tce/万元以下。  相似文献   
102.
Landslide Vulnerability Criteria: A Case Study from Umbria,Central Italy   总被引:9,自引:0,他引:9  
Little is known about the vulnerability to landslides, despite landslides causing frequent and widespread damage to the population and the built-up environment in many areas of the world. Lack of information about vulnerability to landslides limits our ability to determine landslide risk. This paper provides information on the vulnerability of buildings and roads to landslides in Umbria, central Italy. Information on 103 landslides of the slide and slide-earth flow types that have resulted in damage to buildings and roads at 90 sites in Umbria is used to establish dependencies between the area of the landslide and the vulnerability to landslides. The dependencies obtained are applied in the hills surrounding the town of Collazzone, in central Umbria, an area for which a detailed landslide inventory map is available. By exploiting the landslide inventory and the established vulnerability curves, the geographical distribution of the vulnerability to landslides is mapped and statistics of the expected damage are calculated. Reliability and limits of the vulnerability thresholds and of the obtained vulnerability assessment are discussed.  相似文献   
103.
Caballero, Luis A., Alon Rimmer, Zachary M. Easton, and Tammo S. Steenhuis, 2012. Rainfall Runoff Relationships for a Cloud Forest Watershed in Central America: Implications for Water Resource Engineering. Journal of the American Water Resources Association (JAWRA) 48(5): 1022‐1031. DOI: 10.1111/j.1752‐1688.2012.00668.x Abstract: Understanding the basic relationships between rainfall and runoff is vital for effective management and utilization of scarce water resources. Especially, this is important in Central America with widespread potable water shortage during the dry months of the monsoon. Potential good water sources are cloud forests, but little information concerning its potential is available to water supply engineers. Our objective is to define rainfall‐runoff‐base flow relationships for a cloud forest catchment. Flumes were installed for measuring river flow in four subwatersheds in La Tigra National Park, Honduras. One of the four watersheds was a 636‐ha subwatershed (WS1) with 60% cloud forest coverage. Precipitation averaged 1,130 mm/yr over the entire basin. About half of the total rainfall became runoff for the cloud forest watershed whereas, for the adjacent undisturbed forested watershed, the total discharge was <20% of the amount of precipitation. Infiltration rates were generally greater than rainfall rates. Therefore, most rainfall infiltrated into the soil, especially in the upper, steep, and well‐drained portions of the watershed. Direct runoff was generated from saturated areas near the river and exposed bedrock. This research provides compelling evidence that base flow is the primary contributor to streamflow during both wet and dry seasons in cloud forest catchments. Protecting these flow processes over time is critical for the sustained provision of potable water.  相似文献   
104.
This essay evaluates the historical development and current background of human-environment relationships in Italy. The Italian landscape consists of very varied terrain, and periodically suffers from all kinds of natural hazard, especially earthquakes, landslides, floods, and accelerated soil erosion. Some measure of environmental conservation was achieved by the Etruscans and Romans, but the Classical period also marked the beginning of serious lowland waterlogging, malarial infestation, upland soil erosion, and deforestation, which all increased during the Middle Ages. From the Renaissance to the 18th century, there was a diffusion of planned landscapes and carefully managed estates; but by the 20th century, many rural areas could not support growing populations and much land was in need of improvement. Underdevelopment and latifundium agriculture increased the vulnerability to environmental hazards of the Mezzogiorno (Italian South), while the subsequent disappearance of the peasant culture seems not to have led to greatly improved conservation or land management. Poorly farmed or managed landscapes and poorly maintained historic towns have undergone some virtually irreversible degradation, especially with respect to landslides and earthquake damage. Elsewhere in Italy, unchecked urbanization, weak planning laws, and their inadequate enforcement have helped both to reduce environmental quality, by overdevelopment of valued landscapes, and to increase natural disaster vulnerability, by encouraging occupance of natural hazard zones. Although there are signs that the government is beginning to respond to the cumulative effect of environmental degradation, the measures are insufficient to reverse the overall trend toward decadence that characterizes human-land relationships in Italy.  相似文献   
105.
水的重要性不言而喻,生态化的政治文明为水生态文明建设提供了巨大牵引力。经探讨指出,坚持和完善人民代表大会制度、中国共产党领导的多党合作和政治协商制度、民族区域自治制度以及基层群众自治制度,建立健全水行政权力运行制约和监督体系,充分发挥爱国统一战线在水生态文明建设进程中的作用,能为推进水生态文明建设提供广泛、有效的政治途径。  相似文献   
106.
湖南参与了多个区域旅游合作战略,其中泛珠三角和中部6省合作战略是影响湖南旅游经济发展的两大重要外部力量,两大区域合作给湖南旅游业带来了新的发展机遇。在分析它们给湖南旅游发展带来发展机遇的基础上,提出了建立专门的行政组织来强化区域协调管理、利用区域内旅游资源特性实现旅游资源的联动、借助区域旅游市场的互动实现客源市场丰富的地区对湖南旅游市场的支撑、增加区域旅游合作的地域便捷性等对策。  相似文献   
107.
Over the last fifty years, almost half of the steppe rangeland in the Central Anatolian Region of Turkey (CAR) has been converted to cropland without an equivalent reduction in grazing animals. This shift has led to heavy grazing pressure on rangeland vegetation. A study was initiated in June 2003 using 6 multiscale Modified-Whittaker plots to determine differences in plant composition between areas that have not been grazed in 27 years with neighboring grazed plant communities. A total of 113 plant species were identified in the study area with the ungrazed plots containing 32 plants more than the grazed plots. The major species were Astragalus acicularis, Bromus tomentellus, Festuca valesiaca, Genista albida, Globularia orientalis, Poa bulbosa, and Thymus spyleus ssp rosulans. Grazing impacts on forbs were more pronounced than for grasses and shrubs. Based on Jaccard’s index, there was only a 37% similarity of plant species between the two treatments. Our study led to four generalizations about the current grazing regime and long-term exclosures in the steppe rangeland around the study area: (1) exclosures will increase species richness, (2) heavy grazing may have removed some plant species, (3) complete protection from grazing for a prolonged period of time after a long history of grazing disturbance may not lead to an increase in desirable plant species with a concomitant improvement in range condition, and (4) research needs to be conducted to determine how these rangelands can be improved.  相似文献   
108.
Rebich, Richard A., Natalie A. Houston, Scott V. Mize, Daniel K. Pearson, Patricia B. Ging, and C. Evan Hornig, 2011. Sources and Delivery of Nutrients to the Northwestern Gulf of Mexico From Streams in the South‐Central United States. Journal of the American Water Resources Association (JAWRA) 47(5):1061‐1086. DOI: 10.1111/j.1752‐1688.2011.00583.x Abstract: SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were developed to estimate nutrient inputs [total nitrogen (TN) and total phosphorus (TP)] to the northwestern part of the Gulf of Mexico from streams in the South‐Central United States (U.S.). This area included drainages of the Lower Mississippi, Arkansas‐White‐Red, and Texas‐Gulf hydrologic regions. The models were standardized to reflect nutrient sources and stream conditions during 2002. Model predictions of nutrient loads (mass per time) and yields (mass per area per time) generally were greatest in streams in the eastern part of the region and along reaches near the Texas and Louisiana shoreline. The Mississippi River and Atchafalaya River watersheds, which drain nearly two‐thirds of the conterminous U.S., delivered the largest nutrient loads to the Gulf of Mexico, as expected. However, the three largest delivered TN yields were from the Trinity River/Galveston Bay, Calcasieu River, and Aransas River watersheds, while the three largest delivered TP yields were from the Calcasieu River, Mermentau River, and Trinity River/Galveston Bay watersheds. Model output indicated that the three largest sources of nitrogen from the region were atmospheric deposition (42%), commercial fertilizer (20%), and livestock manure (unconfined, 17%). The three largest sources of phosphorus were commercial fertilizer (28%), urban runoff (23%), and livestock manure (confined and unconfined, 23%).  相似文献   
109.
The amount of water Bulgaria uses for irrigation sharply declined during the transition. Large sections of the existing irrigation systems were abandoned, and those still in use are hardly maintained. Crops such as wheat and barley have replaced more water-intensive crops, such as vegetables, rice, and maize. This problem has an impact on the future development of agriculture and the allocation of the countrys water resources. The central argument is that land fragmentation in the wake of decollectivization and restitution contributes to the irrigation systems abandonment. This article focuses on the institutional factors involved, but also considers additional factors that might have influenced the process. Further, it examines the causes driving these changes and analyzes their effect on irrigation. It is based on a review of the relevant legislation as well as fieldwork in 17 villages located in the Plovdiv region of Bulgaria. The article concludes that institutional settings, in addition to changes in large-scale market forces and the state enforcement mechanism, have contributed to the irrigation decline in Bulgaria.Published online Note: This version was published online in June 2005 with the cover date of August 2004.  相似文献   
110.
Nicaragua, home to the largest remaining extent of rainforest in Central America (total surface area) and to a significant indigenous population, has lost approximately half of its forest cover since 1950. This major and rapid loss of forest cover has been explained as the consequence of an eastward moving agricultural frontier that cuts through the region of Jinotega. If the current deforestation rate continues, the country could lose its remaining forest cover over the course of the next two decades; therefore, it is essential that the dynamics and relationships of land-use and land-cover change (LUCC) in this region are understood. To examine LUCC in Nicaragua over time, Landsat imagery from the southern portion of the region of Jinotega, taken in 1978, 1987, and 1999 was utilized. A remote-sensing method, supervised classification, which allows for the grouping of spectrally similar values for each year, followed by an image change detection analysis (postclassification comparison) was conducted. Groundtruthing (field validation) was conducted in 2006 to validate the data, which yielded increasing overall accuracy rates of 71.68% for 1978, 82.35% for 1987, and 84.38% for 1999. The classification and change detection results showed that if the agricultural cultivation overtook this region, it happened before 1978. Therefore, the possibility that either deforestation did not actually occur along an agricultural frontier or that it was located further east exists; this would be an interesting subject for future studies. There was, however, clear evidence of increased forest cover from 1987 to 1999 near the urban center, correlating with the enforced reforestation law in the city of Jinotega.  相似文献   
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