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91.
Environmental education is essential to the success of Agenda 21. Yet currently it is without focus and effectively side-lined. This paper presents the results of preliminary investigations on the environmental attitudes and knowledge of Indian and Filipino primary and secondary school students, and their readiness to engage in pro-environmental behavior that could involve some change in their personal lifestyle. For the most part, environmental education efforts are embedded mainly into various science subjects. The relationship between environmental education and environmental awareness is analyzed to examine whether schools' environmental education could contribute to the shaping of environmental attitudes. A strategy and accompanying methodology for establishing environmental education is supplied. 相似文献
92.
93.
Large‐scale infrastructure projects commonly have large effects on the environment. The planned construction of the Nicaragua Canal will irreversibly alter the aquatic environment of Nicaragua in many ways. Two distinct drainage basins (San Juan and Punta Gorda) will be connected and numerous ecosystems will be altered. Considering the project's far‐reaching environmental effects, too few studies on biodiversity have been performed to date. This limits provision of robust environmental impact assessments. We explored the geographic distribution of taxonomic and genetic diversity of freshwater fish species (Poecilia spp., Amatitlania siquia, Hypsophrys nematopus, Brycon guatemalensis, and Roeboides bouchellei) across the Nicaragua Canal zone. We collected population samples in affected areas (San Juan, Punta Gorda, and Escondido drainage basins), investigated species composition of 2 drainage basins and performed genetic analyses (genetic diversity, analysis of molecular variance) based on mitochondrial cytb. Freshwater fish faunas differed substantially between drainage basins (Jaccard similarity = 0.33). Most populations from distinct drainage basins were genetically differentiated. Removing the geographic barrier between these basins will promote biotic homogenization and the loss of unique genetic diversity. We found species in areas where they were not known to exist, including an undescribed, highly distinct clade of live bearing fish (Poecilia). Our results indicate that the Nicaragua Canal likely will have strong impacts on Nicaragua's freshwater biodiversity. However, knowledge about the extent of these impacts is lacking, which highlights the need for more thorough investigations before the environment is altered irreversibly. 相似文献
94.
中亚地区粮食生产潜力及发展潜力分析——基于GAEZ方法 总被引:1,自引:0,他引:1
中亚地区因特殊的地理位置和高粮食生产能力,对维护世界粮食安全意义重大,发掘中亚地区粮食生产潜力有助于全球粮食危机缓解。采用GAEZ方法,结合联合国粮农组织数据库,定量分析了中亚地区5个国家、9种粮食作物的潜在单产及潜在面积,并通过控制粮食单产和生产面积的变化提出三种假设,测算出不同假设下中亚地区的粮食生产潜力、发展潜力和发展潜力幅度。结果表明:中亚地区的哈萨克斯坦粮食生产潜力和发展潜力大;小麦、大麦产量有较大提升空间,高粱、黑麦、谷子、燕麦、荞麦产量提升空间小且潜力集中在哈萨克斯坦,但高粱的发展潜力幅度很大。 相似文献
95.
目的分析东亚地区气溶胶的垂直分布特征。方法利用2006—2012年CALIPSO星载激光雷达资料,基于气溶胶光学厚度分析结果,选取有代表性的经度带和纬度带,分别研究东亚大陆东部沿海地区气溶胶的垂直分布和东亚-北太平洋地区沙尘气溶胶的垂直分布。在此基础上,选取三个有代表性的格点,进一步研究华北和华南地区气溶胶的垂直分布及塔克拉玛干沙漠沙尘的气溶胶垂直分布,并对其垂直分布特征曲线进行拟合。结果平均来看,除少数地区个别月份外,东亚地区气溶胶主要出现在近地面附近。东部沿海地区,一定高度以上,气溶胶的消光系数随高度的增加总体上呈指数减小;西北沙尘源区,大致在近地面至对流层中层,沙尘气溶胶的消光系数随高度的增加几乎呈线性递减。气溶胶的垂直分布具有显著的月际变化和地区差异,中纬度地区,亚洲沙尘气溶胶跨北太平洋传输在1—5月份较强。结论高垂直分辨率的CALIPSO资料可作为精细分析气溶胶垂直分布特征的有力工具。 相似文献
96.
A severe dust event occurred from April 23 to April 27, 2014, in East Asia. A state-of-the-art online atmospheric chemistry model, WRF/Chem, was combined with a dust model, GOCART, to better understand the entire process of this event. The natural color images and aerosol optical depth (AOD) over the dust source region are derived from datasets of moderate resolution imaging spectroradiometer (MODIS) loaded on a NASA Aqua satellite to trace the dust variation and to verify the model results. Several meteorological conditions, such as pressure, temperature, wind vectors and relative humidity, are used to analyze meteorological dynamic. The results suggest that the dust emission occurred only on April 23 and 24, although this event lasted for 5 days. The Gobi Desert was the main source for this event, and the Taklamakan Desert played no important role. This study also suggested that the landform of the source region could remarkably interfere with a dust event. The Tarim Basin has a topographical effect as a “dust reservoir” and can store unsettled dust, which can be released again as a second source, making a dust event longer and heavier. 相似文献
97.
Cat Button Maria Adelaida Antonette Mias-Mamonong Bernhard Barth Jonathan Rigg 《Local Environment》2013,18(6):705-722
Sorsogon City is a rapidly urbanising coastal area in the Philippines. Its location, combined with a rapidly changing and growing urban fabric, leaves it vulnerable to both incremental climate change and associated extreme weather events. In this paper, UN-HABITAT data are used to draw out the climate change vulnerabilities and policy responses in Sorsogon City. Vulnerability “hotspots” highlight the spatial intersection of socio-economic justice concerns, particularly in terms of vulnerability to increased cyclone activity. We discuss vulnerabilities of Sorsogon City and its citizens to climate change and measures undertaken through various social, environmental and technical systems and interventions to increase resilience. The paper also attempts to unpick the relationship between the neat, concise reported city and the complexities of urban life using the Sorsogon experiment to consider the limitations of such approaches to governing climate change. We group these under four headings: social simplification in the absence of data; over-governance (and under-representation); quick wins versus strategic investment; and stretching the ecological and vulnerability footprints of the city. The experience of Sorsogon City is then extended to reflect on issues of governance and planning in other Asian coastal cities. 相似文献
98.
Using a Remote Technology in Conservation: Satellite Tracking White-Naped Cranes in Russia and Asia 总被引:1,自引:0,他引:1
99.
Analyzing the carbon dynamics of central European forests: comparison of Biome-BGC simulations with measurements 总被引:2,自引:1,他引:1
Biogeochemical models are often used for making projections of future carbon dynamics under scenarios of global change. The aim of this study was to assess the accuracy of the process-based biogeochemical model Biome-BGC for application in central European forests from the lowlands to upper treeline as a pre-requisite for environmental impact assessments. We analyzed model behavior along an altitudinal gradient across the alpine treeline, which provided insights on the sensitivity of simulated average carbon pools to changes in environmental factors. A second set of tests included medium-term (30 years) simulations of carbon fluxes, and a third set of tests focused on daily carbon and water fluxes. Model results were compared to aboveground biomass measurements, leaf area index recordings as well as net ecosystem exchange (NEE) and actual evapotranspiration (AET) measurements. The simulated medium-term forest growth agreed well with measured data. Also daily NEE fluxes were simulated adequately in most cases. Problems were detected when simulating ecosystems close to the upper timberline (overestimation of measured growth and pool sizes), and when simulating daily AET fluxes (overestimation of measured fluxes). The results showed that future applications of Biome-BGC could benefit much from an improvement of model algorithms (e.g., the Q10 model for respiration) as well as from a detailed analysis of the ecological significance of crucial parameters (e.g., the canopy water interception coefficient). 相似文献
100.
利用区域空气质量模式系统RAQMS,模拟研究了2010年3月东亚地区PM10气溶胶的时空演变,研究了19~23日沙尘暴暴发的过程,并将模拟结果与中国16个城市的PM10地面观测数据进行了比较.结果显示,模式对于PM10和沙尘具有好的模拟能力,可以合理地反映东亚地区PM10的时空分布和沙尘暴的演变过程;观测值和模拟值的总体相关系数达到0.705,两者平均值分别为124.8,165.5mg/m3.2010年3月份东亚地区PM10平均浓度处在较高水平,沙尘气溶胶是PM10的主要组分.3月东亚地区沙尘排放量约110.4Mt,其中68%重新沉降到地表. 相似文献