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171.
Abstract: The Chi-Chi earthquake, which occurred on September 21, 1999, and had a magnitude of 7.3 on the Richter scale, resulted in an extensive landslide that blocked the Ching-Shui Creek in Taiwan, forming a large lake with a storage volume of 40 million m3 . This paper describes an analytical procedure used to perform flow analysis of the Tsao-Ling watershed, which includes the new landslide dammed lake. In this study, a digital elevation model was applied to obtain the watershed geomorphic factors and stage-area storage function of the landslide dammed lake. Satellite images were used to identify the landslide area and the land cover change that occurred as a result of the earthquake. Two topography-based runoff models were applied for long term and short term streamflow analyses of the watershed because the watershed upstream of the landslide dam was ungauged. The simulated daily flow and storm runoff were verified using limited available measured data in the watershed, and good agreement was obtained. The proposed analytical procedure for flow analysis is considered promising for application to other landslide dammed lake watersheds. 相似文献
172.
173.
介绍了eCognition软件在生态遥感监测工作中的应用。以高分辨率QuickBird,Worldview-1,IKONOS卫星数据为主要信息源,辅以SPOT,TM,ETM和中巴地球资源卫星CBERS等卫星数据,利用不同波段的组合图像,通过目视解译、人机交互解译、计算机自动识别与信息提取等方法,解译本溪典型区域不同时期矿山开采、林地、农田、城镇、道路等生态环境要素变化。 相似文献
174.
本文介绍了可拓学理论与可拓数据挖掘技术的基本概念与基本方法,并将可拓数据挖掘技术用于“5·12”汶川地震空间电离层电场文本数据文件的处理.利用自行开发的数据挖掘软件进行数据分类,在震前10天数据中,得到了2个关联度异常文件,并计算了挖掘知识的支持度与可信度. 相似文献
175.
介绍了沈阳市矿山环境遥感调查的内容、方法及遥感解译结果,借以为矿产资源的合理开发、有效管理和科学规划,为矿山环境保护和综合治理提供基础资料和决策依据。 相似文献
176.
阐述了卫星图像提取数据信息的光谱变换法的基本原理和方法,并详细介绍了各种卫星图像的数据变换方程。 相似文献
177.
“环境一号”卫星(HJ-1)在轨测试阶段,选择渤海辽东湾的大连、营口和盘锦地区为典型试验区。对HJ-1A/B星CCD多光谱数据与TM数据进行了比对,并进行了生态环境遥感测试评价研究。 相似文献
178.
选择了不同矿山、矿种,以卫星遥感资料为主要信息源,对矿产资源开发状况及其引发的矿山环境问题进行了遥感调查与监测试验,为矿产资源的合理开发、有效管理和科学规划,为矿山环境保护和综合治理提供了基础资料与决策依据。 相似文献
179.
Model of coral population response to accelerated bleaching and mass mortality in a changing climate
We model coral community response to bleaching and mass mortality events which are predicted to increase in frequency with climate change. The model was parameterized for the Arabian/Persian Gulf, but is generally applicable. We assume three species groups (Acropora, faviids, and Porites) in two life-stages each where the juveniles are in competition but the adults can enter a size-refuge in which they cannot be competitively displaced. An aggressive group (Acropora species) dominates at equilibrium, which is not reached due to mass mortality events that primarily disadvantage this group (compensatory mortality, >90% versus 25% in faviids and Porites) roughly every 15 years. Population parameters (N individuals, carrying capacity) were calculated from satellite imagery and in situ transects, vital rates (fecundity, mortality, and survival) were derived from the model, field observations, and literature. It is shown that populations and unaltered community structure can persist despite repeated 90% mortality, given sufficiently high fecundity of the remaining population or import from connected populations. The frequency of disturbance determines the dominant group—in low frequency Acropora, in high frequency Porites. This is congruent with field observations. The model of an isolated population was more sensitive to parameter changes than that of connected populations. Highest sensitivity was to mortality rate and recruitment rate. Community composition was sensitive to spacing of disturbances and level of catastrophic mortality. Decreased mortality led to Acropora dominance, increased mortality led to Acropora extinction. In nature, closely spaced disturbances have severely disadvantaged Acropora populations over the last decade. Unless a longer (>10 years) disturbance-free interval can be maintained, a permanent shift away from Acropora dominance will be observed. A mortality rate of 99% in Acropora, as observed in 1996, is not sustainable if repetitive and neither is a disturbance frequency <15 years—each leading to population collapse. This shows that the severity and/or the spacing of the 1996–1998–2002 disturbances were unusual in frequency and duration. 相似文献
180.
基于卫星遥感的秸秆焚烧监测及对空气质量影响分析 总被引:20,自引:0,他引:20
每年6月是我国小麦收割的主要时节,也是秸秆焚烧发生的严重时期.利用卫星遥感技术监测2007年6月全国秸秆焚烧状况,并以某市为例,结合气象资料分析秸秆焚烧对环境空气质量的影响.研究结果表明,秸秆焚烧主要分布在冬小麦生产区,华北平原是秸秆焚烧集中区域,火点数占全国的86.9%;秸秆焚烧主要发生在6月上半月,火点数占全月的87.3%.相关分析表明,该市700、800 km范围缓冲区内火点数变化趋势与空气污染指数有较好一致性,相关系数均达0.54,当秸秆焚烧发生在不利于污染物扩散的气象条件下时,将导致空气质量明显下降. 相似文献