Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff...Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.展开更多
Since the beginning of the 21st century,major earthquakes have frequently occurred worldwide.To explore the impact of astronomical factors on earthquakes,in this study,the statistical analysis method of correlation is...Since the beginning of the 21st century,major earthquakes have frequently occurred worldwide.To explore the impact of astronomical factors on earthquakes,in this study,the statistical analysis method of correlation is used to systematically analyze the effects of astronomical factors,such as solar activity,Earth’s rotation,lunar declination angle,celestial tidal force,and other phenomena on M≥8 global earthquakes at the beginning of the 21st century.With regard to solar activity,this study focuses on the analysis of the 11-year and century cycles of solar activity.The causal relationship of the Earth’s rotation is not obvious in this work and previous works;in contrast,the valley period of the solar activity century cycle may be an important astronomical factor leading to the frequent occurrence of global earthquakes at the beginning of the 21st century.This topic warrants further study.展开更多
基于MOD16数据,计算作物缺水指数(Crop Water Stress Index,CWSI),结合汾河流域气象站点数据、植被指数数据和土地利用数据,采用差值法、线性趋势法和相关分析法,分析汾河流域2000—2021年干旱时空变化特征。结果表明:(1)CWSI能有效监...基于MOD16数据,计算作物缺水指数(Crop Water Stress Index,CWSI),结合汾河流域气象站点数据、植被指数数据和土地利用数据,采用差值法、线性趋势法和相关分析法,分析汾河流域2000—2021年干旱时空变化特征。结果表明:(1)CWSI能有效监测汾河流域旱情,其与10 cm土壤相对湿度呈显著负相关。(2)汾河流域CWSI空间分布差异明显,呈现出南湿北旱的特点。(3)汾河流域CWSI年际变化较为平稳,而月变化波动较大,5月CWSI达到年内峰值。(4)汾河流域不同生长期内干旱情况差异显著,生长季前期(4—5月)特旱区占汾河流域总面积的48.55%;生长季中期(6—8月)基本全域无旱;生长季后期(9—10月),仅11.17%的地区发生干旱。(5)不同土地利用类型干旱程度不同,CWSI从小到大依次为:林地(0.686)<草地(0.749)<耕地(0.751)<未利用地(0.758)<城镇(0.765)。本研究结果可为汾河流域旱情监测和抗旱决策的制定提供科学数据支撑。展开更多
基金supported by the project of the China Geological Survey(No.DD20221746)the National Natural Science Foundation of China(Grant Nos.41101086)。
文摘Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.
文摘Since the beginning of the 21st century,major earthquakes have frequently occurred worldwide.To explore the impact of astronomical factors on earthquakes,in this study,the statistical analysis method of correlation is used to systematically analyze the effects of astronomical factors,such as solar activity,Earth’s rotation,lunar declination angle,celestial tidal force,and other phenomena on M≥8 global earthquakes at the beginning of the 21st century.With regard to solar activity,this study focuses on the analysis of the 11-year and century cycles of solar activity.The causal relationship of the Earth’s rotation is not obvious in this work and previous works;in contrast,the valley period of the solar activity century cycle may be an important astronomical factor leading to the frequent occurrence of global earthquakes at the beginning of the 21st century.This topic warrants further study.
文摘基于MOD16数据,计算作物缺水指数(Crop Water Stress Index,CWSI),结合汾河流域气象站点数据、植被指数数据和土地利用数据,采用差值法、线性趋势法和相关分析法,分析汾河流域2000—2021年干旱时空变化特征。结果表明:(1)CWSI能有效监测汾河流域旱情,其与10 cm土壤相对湿度呈显著负相关。(2)汾河流域CWSI空间分布差异明显,呈现出南湿北旱的特点。(3)汾河流域CWSI年际变化较为平稳,而月变化波动较大,5月CWSI达到年内峰值。(4)汾河流域不同生长期内干旱情况差异显著,生长季前期(4—5月)特旱区占汾河流域总面积的48.55%;生长季中期(6—8月)基本全域无旱;生长季后期(9—10月),仅11.17%的地区发生干旱。(5)不同土地利用类型干旱程度不同,CWSI从小到大依次为:林地(0.686)<草地(0.749)<耕地(0.751)<未利用地(0.758)<城镇(0.765)。本研究结果可为汾河流域旱情监测和抗旱决策的制定提供科学数据支撑。
