秦岭南北风速时空变化及突变特征分析

根据秦岭南北47个气象站1960~2011年逐月风速和气温资料,采用样条曲线插值法(Spline)、Pettitt突变点检验、气候倾向率和相关分析等方法对该区风速的空间分布、时空演变特征及其可能影响因素进行了分析。结果表明:①秦岭南北风速空间分布呈东高西低、北高南低格局,按其大小排序为秦岭以北>秦岭南坡>汉水流域>巴巫谷地。四季风速排序为春季>冬季>夏季>秋季,均以秦岭以北最大。②近52 a来,秦岭南北整体和各子区年平均风速呈现一致的显著下降趋势,下降最快的为秦岭南坡,最慢的为汉水流域。四季风速下降速率排序为冬季>春季>秋季>夏季。③年和季节尺度风速的突变集中出现在1969~1974、1978~1981和1990~1994年间,秦岭南北整体于1981年突变。④气象台站周边的城市化发展和风速测量仪器的更换都对风速的变化产生了一定影响,但都不是风速显著下降的主要原因,大气环流变化和气候变暖才是造成风速减小的可能原因。     

基于岩石物理实验的时移地震研究

时移地震技术是油田开发阶段动态检测的一个重要手段.岩石物理实验室能实现模拟油气田在开采过程中其储层参数变化对岩石弹性参数的影响.本文基于岩石物理实验及地震正演模拟,分析了X气田在开采过程中其孔隙压力下降及水不断侵入情况下,进行时移地震监测的可行性及其主要影响因素.     

甘肃东南地区构造活动与2013年岷县—漳县MS6.6级地震孕震机制

位于南北地震带中北段的甘东南地区,其构造变形和构造活动特征与青藏高原向北东方向的扩展密切相关,该地区复杂的构造几何形态主要受控于东昆仑断裂和西秦岭北缘断裂,区域新构造运动主要动力来源于青藏高原向北东的扩展.近年来,甘东南地区中强地震频发,本文主要通过对该地区构造活动特征、历史地震等资料的综合分析讨论,结合地球物理、地震学和野外调查等资料,认为青藏高原东北部东昆仑断裂的向北挤压和向东的运动是该地区构造应力集中的主要原因,也是该地区中强地震的主要孕震环境和机制,而西秦岭北缘断裂的走滑及向南北两侧逆冲“花状构造”是临潭—宕昌断裂带上中强地震频繁发生的一个重要动力因素.2013年7月22日发生在甘肃岷县—漳县的M_S6.6级地震正好位于临潭—宕昌断裂带中东段上,是该断裂分段不均匀活动的结果.     

Investigating the uncertainty and transferability of parameters in SWAT model under climate change

ABSTRACT

There is an implicit assumption in most work that the parameters calibrated based on observations remain valid for future climatic conditions. However, this might not be true due to parameter instability. This paper investigates the uncertainty and transferability of parameters in a hydrological model under climate change. Parameter transferability is investigated with three parameter sets identified for different climatic conditions, which are: wet, intermediate and dry. A parameter set based on the baseline period (1961–1990) is also investigated for comparison. For uncertainty analysis, a k-simulation set approach is proposed instead of employing the traditional optimization method which uses a single best-fit parameter set. The results show that the parameter set from the wet sub-period performs the best when transferred into wet climate condition, while the parameter set from the baseline period is the most appropriate when transferred into dry climate condition. The largest uncertainty of simulated daily high flows for 2011–2040 is from the parameter set trained in the dry sub-period, while that of simulated daily medium and low flows lies in the parameter set from the intermediate calibration sub-period. For annual changes in the future period, the uncertainty with the parameter set from the intermediate sub-period is the largest, followed by the wet sub-period and dry sub-period. Compared with high and medium flows/runoffs, the uncertainty of low flows/runoffs is much smaller for both simulated daily flows and annual runoffs. For seasonal runoffs, the largest uncertainty is from the intermediate sub-period, while the smallest is from the dry sub-period. Apart from that, the largest uncertainty can be observed for spring runoffs and the lowest one for autumn runoffs. Compared with the traditional optimization method, the k-simulation set approach shows many more advantages, particularly being able to provide uncertainty information to decision support for watershed management under climate change.

EDITOR Z.W. Kundzewicz ASSOCIATE EDITOR not assigned     

Plant Species Richness Increased Belowground Plant Biomass and Substrate Nitrogen Removal in a Constructed Wetland

The effects of plant species richness on both above‐ and belowground plant biomass, plant nitrogen (N) pool size, and substrate N concentrations were studied in a full‐scale subsurface vertical‐flow constructed wetland (CW). Results showed that (i) plant species richness increased belowground plant biomass and its N pool size but had no effect on aboveground plant biomass and its N pool size; (ii) plant species richness increased substrate N removal, especially ammonium N removal; and (iii) plant species richness had no effect on plant N use efficiency, suggesting that the N pool size increased with increasing plant species richness. More N accumulation could be removed through harvesting plant biomass. We concluded that the N removal performance of the CW improved by plant species richness through increasing belowground biomass and relevant N pool size.     

我国开展测绘地理信息一致性测试的探讨

测绘地理信息标准化是保障地理信息产业健康快速发展的重要技术手段,一致性测试作为一种标准化的检测手段已广泛应用于信息技术、工业自动化等多个领域,如何建立与我国国情相适应的测绘地理信息一致性测试评价体系是当前面临的重要课题。首先介绍一致性测试理论的发展及应用现状,然后对一致性测试的特点进行深入分析,提出在测绘地理信息领域开展一致性测试工作的特殊性和必须考虑的问题,最后结合测绘地理信息领域的现状探讨如何建立测绘地理信息一致性测试评价体系。     

北斗卫星导航系统电离层模型应用评价

利用北斗接收机接收到的北斗系统K8电离层模型,与同时段欧洲定轨中心提供的电离层模型为基准进行对比,对北斗卫星导航系统在不同地区不同时段的改正效果进行分析;并以中纬度北京地区为例对不同电离层改正模型下的定位误差进行分析比较,从而对北斗系统K8电离层模型的改正效果进行评价。     

湘西南铜山岭地区钨多金属矿床地质特征及成矿机制探讨 ——以祥霖铺矿床为例

祥霖铺夕卡岩型钨多金属矿床位于南岭纬向构造带的中段,矿床产于NE向、NW向和EW向断裂的交汇处,矿化集中赋存于背斜的倾伏端附近.通过对矿床地质特征、地球物理、地球化学特征等方面的研究,认为燕山期构造运动所导致的岩浆活动为矿床的形成提供了大量热源,区内的断裂构造为成矿提供了良好的构造条件,中泥盆统棋梓桥组在成矿过程中提供了大量的物质来源;在夕卡岩化过程中形成了不同的矿物组合,成矿过程可以分为2个成矿期、4个成矿阶段;预测在矿区的西部有望找到隐伏矿体.     

The 2010 Yushu earthquake triggered landslide hazard mapping using GIS and weight of evidence modeling

The Yushu County, Qinghai Province, China, April 14, 2010, earthquake triggered thousands of landslides in a zone between 96°20′32.9″E and 97°10′8.9″E, and 32°52′6.7″N and 33°19′47.9″N. This study examines the use of geographic information system (GIS) technology and Bayesian statistics in creating a suitable landslide hazard-zone map of good predictive power. A total of 2,036 landslides were interpreted from high-resolution aerial photographs and multi-source satellite images pre- and post-earthquake, and verified by selected field checking before a final landslide-inventory map of the study area could be established using GIS software. The 2,036 landslides were randomly partitioned into two subsets: a training dataset, which contains 80 % (1,628 landslides), for training the model; and a testing dataset 20 % (408 landslides). Twelve earthquake triggered landslide associated controlling parameters, such as elevation, slope gradient, slope aspect, slope curvature, topographic position, distance from main surface ruptures, peak ground acceleration, distance from roads, normalized difference vegetation index, distance from drainages, lithology, and distance from all faults were obtained from variety of data sources. Landslide hazard indices were calculated using the weight of evidence model. The landslide hazard map was compared with training data and testing data to obtain the success rate and predictive rate of the model, respectively. The validation results showed satisfactory agreement between the hazard map and the existing landslide distribution data. The success rate is 80.607 %, and the predictive rate is 78.855 %. The resulting landslide hazard map showed five classes of landslide hazard, i.e., very high, high, moderate, low and very low. The landslide hazard evaluation map should be useful for environmental recovery planning and reconstruction work.     

抗差自适应卡尔曼滤波在GPS精密单点定位中的应用

卡尔曼滤波是GPS精密单点定位中最常用的参数估计方法.理论上讲,随着观测数据的增多,通过卡尔曼滤波可以得到更精确的状态估值,但有时由于状态异常或发生大的周跳等原因,使得状态估值与实际状态之间的误差较大,滤波会发生发散现象,为此,本文提出了将抗差自适应滤波模型运用到精密单点定位中,通过算例分析显示,该方法将显著提高定位结...