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深州地区浅层地下水同位素组成及其指示意义 被引量:1
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作者 冯欣 高业新 +2 位作者 张冰 崔浩浩 张亚哲 《水资源与水工程学报》 CSCD 2018年第2期39-44,共6页
以国土资源部地下水科学深州基地80 m范围内的4眼综合试验井为研究对象,通过开展同位素分析,讨论了浅层地下水氢氧同位素及硼同位素组成,确定了咸水、微咸水的来源。研究表明:咸水、微咸水的氢氧同位素普遍偏负,其数值均未超出海相成因... 以国土资源部地下水科学深州基地80 m范围内的4眼综合试验井为研究对象,通过开展同位素分析,讨论了浅层地下水氢氧同位素及硼同位素组成,确定了咸水、微咸水的来源。研究表明:咸水、微咸水的氢氧同位素普遍偏负,其数值均未超出海相成因咸水δ^(18)O和δD的特征值,咸水δ^(11)B‰明显低于海水的δ^(11)B‰值并介于海水和陆相淡水的δ11B‰值之间,该数值表明了区域地下水的陆相成因;经计算两微咸水含水层咸水混入比例呈逐年增加的趋势,这与含水层TDS及Cl^-含量增加显示出的咸化呈现一致的情况,进一步证明了研究区微咸水出现了一定程度的咸化。 展开更多
关键词 浅层地下水 氢氧同位素 硼同位素 地下水咸化 深州地区
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早熟梨西子绿在河北深州的表现
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作者 李赛 《西北园艺(果树)》 2004年第4期30-31,共2页
关键词 早熟梨 西子绿 河北 深州地区 性状表现
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Morlet小波在降雨的多时间尺度分析中的应用 被引量:29
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作者 祁顺杰 陈皓锐 《南水北调与水利科技》 CAS CSCD 2010年第3期79-82,共4页
利用河北省深州地区5个降雨站近30年资料分析了该地区降雨量变化的多时间尺度特征。结果表明:该地区降雨量年内分配极为不均,主要降雨量集中在7月、8月份;30年降雨量呈现微弱下降趋势,且年际变异大。近30年降雨量呈现明显阶段性,依据丰... 利用河北省深州地区5个降雨站近30年资料分析了该地区降雨量变化的多时间尺度特征。结果表明:该地区降雨量年内分配极为不均,主要降雨量集中在7月、8月份;30年降雨量呈现微弱下降趋势,且年际变异大。近30年降雨量呈现明显阶段性,依据丰枯特点可分为四个阶段。小波分析表明年降雨量具有5年和10年尺度周期,并揭示了两个主周期震荡强弱和相位波动的年间分布情况,最后还分析了降雨突变年份并利用时序累积曲线法对结论进行了验证。 展开更多
关键词 降雨量 多时间尺度 小波分析 周期 突变 深州地区
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Exploration and Research of Deep Crustal Structures in the Zhangzhou Basin and Its Vicinity 被引量:2
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作者 Zhu Jinfang Fang Shengming +4 位作者 Zhang Xiankang Qu Guosheng Huang Zonglin Zhang Chengke Zhao Jinren 《Earthquake Research in China》 2006年第4期412-425,共14页
The Zhangzhou basin is located at the middle section of the southeast coast seismic zone of the mainland of China. Using high-resolution refraction and wide-angle reflection/refraction seismic profiling of Zhangzhou b... The Zhangzhou basin is located at the middle section of the southeast coast seismic zone of the mainland of China. Using high-resolution refraction and wide-angle reflection/refraction seismic profiling of Zhangzhou basin and its vicinity, we have obtained the crustal geometric structure and velocity structure as well as the geometric configuration and structural relationship between the deep and shallow fractures. The results show that the crust in the region is divided into the upper crust and lower crust. The thickness of the upper crust is 16.5km- 18.8km, and that of the lower crust is 12.0km- 13.0km. The upper crust is further divided into an upper and lower section. In the lower section of the upper crust, there is a low-velocity layer with a velocity of about 6.00km/s; the depth of the top surface of the low-velocity layer is about 12.0km, and the thickness is about 5.0km. The lower crust is also divided into an upper and lower section. The depth of Moho is 29.0km- 31 .8km There are 6 normal faults in the shallow crust in this region, and most of them extend downwards to a depth of less than 4kin, the maximum depth is about 5km. Below the shallow normal faults, there is a conjectural high-dip angle deep fault zone. The fault zone extends downwards till the Moho and upwards into the low-velocity layer in lower section of the upper crust. The deep and shallow faults are not tectonically connected. The combination character of deep and shallow structures in the Zhangzhou basin indicates that the Jiulongjiang fault zone is a deep fault zone with distinct characteristics and a complex deep and shallow structure background. The acquisition of deep seismic exploration results obviously enhanced the reliability of explanation of deep-structural data and the exploration precision of the region. The combination of deep and shallow structures resulted in uniform explanation results. The delamination of the crust and the characteristic of the structures are more precise and explicit. We discovered for the first time the combination characteristics of extensional structures and listric faults in the upper crust. This is not only helpful to the integrative judgment of earthquake risk in Zhangzhou and its vicinity, but also of importance for deepening the knowledge of deep dynamic processes in the southeast coast seismic zone. 展开更多
关键词 High-resolution refraction Deep seismic wide-angle reflection/refraction Crust-mantle structure Deep structure
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Policy Assessment and Recommendations for Forestry-based Ecological Poverty Alleviation: An Empirical Study from the Prefectures of Nujiang and Aba, Southwestern China 被引量:4
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作者 WANG Yaming QIN Fanding +4 位作者 ZHAO Guangshuai FENG Qinliang WU Qiong LI Yang YI Xutong 《Journal of Resources and Ecology》 CSCD 2021年第1期110-123,共14页
China has adopted a long-term campaign against poverty. In recent decades, there is an increasing understanding that ecological poverty alleviation can meet the dual goals of environmental protection and rural poverty... China has adopted a long-term campaign against poverty. In recent decades, there is an increasing understanding that ecological poverty alleviation can meet the dual goals of environmental protection and rural poverty reduction. China is pivoting towards forestry-based poverty reduction in the severely poverty-stricken areas. However, several key factors remain elusive, including the extent to which the poor people benefit from forestry programs, whether they are satisfied with the policies and whether the policies are effective for poverty alleviation. Based on data collected through a questionnaire survey of 79 households in the prefectures of Nujiang and Aba, southwestern China, the analytic hierarchy process(AHP) approach was used to examine the effectiveness of the forestry-based poverty alleviation policy. The results showed that four poverty alleviation pathways, including industry, employment, micro-finance and pairing assistance in villages, had obviously increased the incomes of the filing poor households and solved the problem of "Two Worries-free and Three Guarantees". The poor were satisfied with the forestry-based ecological poverty alleviation policies and these policies had good effects in fighting against poverty. However, there are still some shortcomings, such as a lack of active participation, imperfect targeted identification, lack of funds and limited sources of funds during the policy implementation. Our results highlight the importance of the forestry industry and the public welfare position in the alleviation of poverty in the poverty-stricken areas. Synergies between ecological protection and poverty reduction are possible through sound forestry-based policies. This article recommends five policies to simultaneously realize the potential of poverty alleviation and environment protection through forestry development. 展开更多
关键词 forest-based ecological poverty alleviation forestry policy assessment and policy recommendation the"Two Worries-free and Three Guarantees" severely poverty-stricken areas the"Three Regions and Three Prefectures"
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