中国西南地区纵向岭谷地形对区域生态地理格局的作用(英文)

China’s southwestern special terrain pattern as parallel arrangement between longitudinal towering mountains and deep valleys has significant effects on the differentiation of local natural environment and eco-geographical pattern in this region.The 1:50,000 Digital Elevation Model(DEM) data of Longitudinal Range-Gorge Region(LRGR),meteorological observation data from the station establishment to 2010,hydrological observation data,Normalized Difference Vegetation Index(NDVI) and Net Primary Productivity(NPP) products of MOD13 and MOD17 as well as 1:1,000,000 vegetation type data were used.Moisture indices including surface atmospheric vapor content,precipitation,aridity/humidity index,surface runoff,and temperature indices including average temperature,annual accumulated temperature,total solar radiation were selected.Based on ANUSPLIN spline function,GIS spatial analysis,wavelet analysis and landscape pattern analysis,regional differentiation characteristics and main-control factors of hydrothermal pattern,ecosystem structure and function in this region were analyzed to reveal the effects of terrain pattern on regional differentiation of eco-geographical elements.The results show that:influenced by terrain pattern,moisture,temperature and heat in LRGR have shown significant distribution characteristics as intermittent weft differences and continuous warp extension.Longitudinal mountains and valleys not only have a north-south corridor function and diffusion effect on the transfer of major surface materials and energy,but also have east-west barrier function and blocking effect.Special topographic pattern has important influences on vegetation landscape diversity and spatial pattern of ecosystem structure and function,which is the main-control factor on vegetation landscape diversity and spatial distribution of ecosystem.Wavelet variance analysis reflects the spatial anisotropy of environmental factors,NDVI and NPP,while wavelet consistency analysis reveals the control factors on spatial distribution of NDVI and NPP as well as the quantitative relationship with control degree.Special terrain pattern in LRGR is the major influencing factor on eco-geographical regional differentiation in this region.Under the combined effect of zonality and non-zonality laws with "corridor-barrier" function as the main characteristic,special spatial characteristics of eco-geographical regional system in LRGR is formed.     

Role of the Wide-angle OBS Seismic Exploration in the Research of Marine Sedimentary Basin

Marine sedimentary basin is an important tectonic unit in the earth, and the evolution of marine sedimentary basin involves a series of the coupling and evolution of geodynamic mechanism such as the crust-mantle, the lithosphere-asthenosphere, the strata-fluid deposition. Therefore, the study of marine sedimentary basin dynamics includes deep structure state of earth, material composition and regional tectonic evolution, and also internal structure, tectonic characteristics and pore fluid characteristics strata of the basin. Wide angle Ocean Bottom Seismometer (OBS) seismic exploration is a marine geophysical survey method originated and developed since 1980’s and 1990’s, which has the advantages of strong penetration capability, high seismic imaging precision and reception of both P-wave and S-wave, and playing an increasing significant role in the research of marine sedimentary basin at the aspect of regional tectonic evolution, internal structure and pore fluid development characteristics of strata in recent years. In the study of passive continental margin, the crustal structure acquired from wide angle OBS seismic data provides the direct evidence that divides the passive continental margins into magma-poor and magma-dominated ones, and the degree of thinning and spatial variation characteristics of crust provide constraints for dynamics simulations of tectonic evolution in marine sedimentary basin. In the study of the structure features of basin, wide angle OBS seismic exploration fills in gaps at the aspect of investigation depth and complex geological structure in conventional multi-channel seismic survey, and acquires overpressure distribution status of basin according to the velocity structure characteristics of strata, and then infer the basin sedimentation velocity and pore fluid characteristics. In the study of internal fluid system in marine sedimentary basin, it reveals the velocity structure of natural gas hydrate reservoir through the analysis and processing of wide angle OBS seismic data, and calculates the thickness of natural gas hydrate reservoir and the content of hydrate and free gas in pore based on the velocity variation. Of course, the future wide angle OBS seismic exploration in the aspect of dynamic evolution and mechanism research in marine sedimentary basin will play a more important role with the development of marine seismic exploration technology, the improvement of data processing and instrument parameters.     

中国地震灾害人口死亡风险定量评估(英文)

基于地震灾害风险形成机理,在建立人口震害脆弱性曲线与确定地震发生参数的基础上,本文利用评估模型对我国Ⅴ-Ⅺ地震烈度下各县域单元的人口死亡风险进行评估并分析其空间分布格局。主要研究内容有:(1)首次采用基于过去—现在—未来的多方面地震孕灾环境资料来处理地震发生的可能性。具体综合历史地震综合烈度、地震活动断裂带分布、地震动峰值加速度三方面来确定全国2355个县域单元的地震发生参数;(2)利用1990-2009年我国历史地震灾情数据,对地震烈度与人员死亡率之间进行线性拟合,建立适合我国地震灾害风险评估的震害人口死亡脆弱性曲线;(3)利用震害风险评估模型对我国各县域单元的人口死亡风险进行定量评估,并分析风险空间分布格局,彻底摸清Ⅴ-Ⅺ地震烈度下我国各县域单元的地震灾害人口死亡风险。研究表明:在不同地震烈度下,我国广大的东、中部地区面临更高的风险,而西部的人口死亡风险相对较低。高风险区域呈零星状分布于山东与江苏大部、安徽北部、黑龙江与吉林东部等人口分布较密集且孕灾环境发育完备的区域。而无风险区域在全国范围内呈斑块状散布,分布格局基本保持不变。     

The effects of land-use types and conversions on desertification in Mu Us Sandy Land of China

Based on multi-temporal remotely sensed materials of both 1985 and 2000, we analyzed the effects of land-use types and their conversions on desertification in Mu Us Sandy Land in the agro-pastoral transitional zone of north central China. In this study, the desertified land was classified into five degrees: potential, light, medium, severe and extreme. The results indicate that the extent of desertification expands slightly, while desertification degree is enhanced significantly. About 22.35% of the total land area in the study area is in the desertification course, and the expanded area of both severely and extremely desertified land accounts for 3.67% of the total area of Mu Us Sandy Land. About 9053 km2 of area witnessed changes in land-use types between 1985 and 2000, which accounted for 10.75% of the total. More importantly, the area of conversions among cultivated land, forestland and rangeland added up to 971.6 km2. This research reveals that both improper land-use types and conversions could accelerate the desertification process. Both cultivated land and forestland have more effects on the desertification development than rangeland. Some land-use type conversions, such as rangeland to cultivated land, rangeland to forestland and forestland to cultivated land, are attributed to the acceleration of the desertification development while the opposite can control the desertification development.     

1954-2011年盐城市气温和降水变化特征

根据盐城市2个观测站点1954-2011年逐月平均气温和降水资料,采用线性趋势分析、M-K检验、滑动t检验等方法,分析了盐城市气温和降水的气候变化特征。结果表明:盐城市年平均气温以0.24℃/10a的速率显著增加,其中,春季的升温速率最大(0.32℃/10a),秋季和冬季次之(分别为0.27℃/10a和0.28℃/10a),夏季最小(0.08℃/10a)且不显著。年降水量以17.1 mm/10a的速率呈弱的下降趋势,春、夏、秋季降水量均呈弱的下降趋势,而冬季降水量则呈弱的增加趋势。全年和四季(除春季)平均气温在20世纪90年代后升高明显,进入21世纪后升温幅度明显加大。年降水量具有"减-增-减"的年代际变化特征,四季降水距平各自波动特征不同,春、夏季降水量偏多期在20世纪50年代中后期和90年代,秋季降水量偏多期在50年代中后期、60年代和80年代,冬季降水量偏多期为90年代以后,其余年代为降水量偏少期。年平均气温在1993年发生突变式增温,春、夏、秋、冬四季气温突变时间分别在1993年、2000年、1997年和1991年。全年和四季降水量都没有明显突变现象。     

Climate Changes in Northeastern China During Last Four Decades

The northeastern China is a sensitive region of climate change, whose detailed trend of climate changes is highly interesting. In this study, this kind of variation trend was analyzed. Potential evapotranspiration (PE) and moisture index (MI) were modeled by using Thornthwaite scheme based on the observation data of 1961-2004 from 94 meteorological stations. To describe the climate fluctuation in the northeastern China in 1961-2004, the linear regression method was used to analyze the variation trends of mean annual temperature, mean annual precipitation, PE and MI. Mann-Kendall method was used to test the significant difference. The results show a general increasing tendency in mean annual temperature, mean annual precipitation, PE and MI. However increasing tendency was more significant in mean annual temperature and PE than in mean annual precipitation and MI. Analysis of seasonal climate variation indicates that there showed positive trends in winter and in spring, while the positive trend was more significant in winter than in spring. Furthermore, the relations between climate changes and geographical factors were analyzed, the results show that both climate factors and their interannual variability were correlated to latitude, longitude and altitude, suggesting that latitude is the most climate factor affecting climate changes, followed by altitude and longitude.     

Significance of pollen and spores distribution to the barrier function of the Longitudinal Range-Gorge Region, Southwest China

35 surface soil samples and 28 profile soil samples were collected in Longitudinal Range-Gorge Region, Southwest China. The distribution of pollen and spores and their relationship with the environment are analyzed. The results show that there are significant differences in pollen and spores taxa, amounts, dominant taxa and florae between the eastern and western flanks of the Ailao Mountain. There are more pollen and spores taxa, a greater amount and complexity on the western flank of the mountain than those on the eastern flank, while the dominant taxa are more centralized and prominent on the eastern flank of the Ailao Mountain. As for the plant florae distribution, there are significant differences in the number of taxa and composition between the eastern and the western flanks. The analysis of profile pollen and spores assemblage shows that its trends of variation are basically in accordance with the surface pollen and spores, which are also indicators of the environmental differences between the two flanks of the mountain. These significant spatial differences of pollen and spores are very close to the regional topography and climate difference. The mountain running perpendicular to the moisture-laden air flow serves as a barrier and the monsoon circulations the east and the west of the mountain result in different energy-moisture characteristics. We conclude that the main patterns of the pollen and spores can be attributed to the environmental differences.     

福建天然洞穴的主要类型及其特征

本文将福建天然洞穴划分为石灰岩溶洞、火山岩构造— 差异风化洞、花岗岩崩塌堆叠洞、红层层(节)理洞和沿海的海蚀洞等主要类型,并讨论了各类洞穴的基本特征。      

人类活动影响下的北京地区气候承载力初步评估

重点考虑北京地区的气候条件、环境特点以及社会经济发展过程中的主要人类活动,从气候资源现状、人类活动强度和生态环境状态3个基本要素层出发,构建人类活动影响下的北京地区气候承载力评估指标体系,评估人类活动影响下的北京地区气候承载力情况,分析了气候承载力构成要素的空间分布及相对水平,解析了不同区县气候承载力的相对状况及主要制约因子。结果表明,北京地区气候承载力指数（I_CCC）在0.24~2.24之间变化,其中延庆县、密云县、昌平区的气候承载力较高,东城区、西城区、顺义区、石景山区、丰台区、房山区、朝阳区的气候承载力相对较差,海淀区、大兴区、怀柔区、门头沟区、平谷区、通州区居中。在各行政区县内部,东城区、西城区、丰台区、顺义区、朝阳区的气候承载力空间差异性较小;而延庆县、怀柔区、门头沟区等郊区气候承载力空间差异性较大,这主要受气候条件和生态环境的区域差异性影响。从气候承载力的构成要素看,怀柔区、延庆县及门头沟区的气候承载力主要受气候资源的限制;城六区和房山区等地的气候承载力主要受人类活动强度及生态环境要素的限制。就气候承载力具体指标而言,东城区、西城区、海淀区、朝阳区主要受人口密度、人均绿地面积以及生产生活排污量的影响;石景山区主要受空气质量较差的影响,房山区则受空气质量差和人均能耗高的影响。     

Seismic structure in the northeastern South China Sea: S-wave velocity and Vp/Vs ratios derived from three-component OBS data

A nearly 500-km-long seismic profile with reflective and refractive wide-angle Ocean Bottom Seismometer (OBS) data and Multi-Channel Seismic (MCS) data was acquired across the northeastern continental margin of the South China Sea (SCS). The S-wave crustal structure and Vp/Vs ratios have been obtained based on a previously published P-wave model using the software RayInvr. Modeling of vertical- and horizontal-component OBS data yields information on the seismic crustal velocities, lithology, and geophysical properties along the OBS-2001 seismic profile. S-wave velocities in the model increase generally with depth but exhibit high spatial variability, particularly from the shelf to the upper slope of the northeastern SCS margin. Vp/Vs ratios also reveal significant lithological heterogeneity. Dongsha–Penghu Uplift (DPU) is a tectonic zone with a thicker crust than adjacent areas and a high magnetic anomaly. With a Vp/Vs of 1.74 and a P-wave velocity of 5.0–5.5 km/s, the DPU primarily consists of felsic volcanic rocks in the upper crust and is similar to the petrology of Zhejiang–Fujian volcanic provinces, which perhaps is associated with a Mesozoic volcanic arc. The ocean–continent transition (OCT) in the northeastern SCS is characterized by a thinning continental crust, volcanoes in the upper crust, and a high velocity layer (HVL) in the lower crust. The S-wave velocity and Vp/Vs ratio suggest that the HVL has a mafic composition that may originate from underplating of the igneous rocks beneath the passive rifted crust after the cessation of seafloor spreading.