宁夏水资源现状、问题及对策

宁夏地处西北内陆干旱地区,水资源极为匮乏,属于重度缺水区,从城市发展和水资源危机的角度出发对宁夏省水资源现状进行研究,以期为宁夏城市可持续发展提供依据.宁夏在开发利用中,主要存在水资源供需矛盾突出、防洪抗灾体系不完善、农村水利基础设施薄弱、水土流失、水污染等水环境问题严重、制约水利发展的体制性和机制性障碍问题还比较突出...     

基于正交设计的旱区棉花膜下滴灌最优化探究

以旱区广大群众最为关心的种植密度,滴水量,施肥量为考虑因子,将棉花单铃重,衣分,籽棉产量作为考查指标,把正交试验设计方案引入高密度棉花膜下滴管研究中.采用归一化处理不同数量级的指标,比以往单独考虑各因素对指标的作用,合理而又更加直观;同时考虑了误差对指标的影响,从而提高了F检验的灵敏度.得出了在膜下滴灌的新疆旱区,土壤...     

利用测井方法识别火山岩岩相方法

利用实际岩石薄片数据及测井数据,通过GR-TH 及GR-AC 交会图方法将松南气田营城组岩石结构划分为熔岩结构、熔结结构和凝灰结构3 种。凝灰结构和熔结结构对应爆发相,熔岩结构对应喷溢相。结合次生孔隙度的大小及岩心、录井信息对出现的6 种亚相: 热碎屑流亚相、热基浪亚相、空落亚相、上部亚相、中部亚相和下部亚相进一步划分,其结果与地质上的岩相亚相基本一致。     

中国陆地海岸线尺度效应研究(英文)

Spatial scale is a fundamental problem in Geography. Scale effect caused by fractal characteristic of coastline becomes a common focus of coastal zone managers and researchers. In this study, based on DEM and remote sensing images, multi-scale continental coastlines of China were extracted and the fractal characteristic was analyzed. The results are shown as follows. (1) The continental coastline of China fits the fractal model, and the fractal dimension is 1.195. (2) The scale effects with fractal dimensions of coastline have significant differences according to uplift and subsidence segments along the continental coastlines of China. (3) The fractal dimension of coastline has significant spatial heterogeneity according to the coastline types. The fractal dimension of sandy coastline located in Luanhe River plain is 1.109. The dimension of muddy coastline located in northern Jiangsu Plain is 1.059, while that of rocky coastline along southeastern Fujian is 1.293. (4) The length of rocky coastline is affected by scale more than that of muddy and sandy coastline. Since coastline is the conjunction of sea, land and air surface, the study of coastline scale effect is one of the scientific bases for the researches on air-sea-land interaction in multi-scales.     

几株真菌对铊吸附作用的初步研究

铊是13种优先控制的有毒有害重金属元素之一,研究微生物与铊之间的相互作用有重要的理论意义和应用价值。在黔西南滥木厂铊矿区采集土壤和沉积物,借助平板筛选法在铊浓度为1000 mg/L水平筛选得到九株高耐受性菌株,用于真菌对铊的胞外吸附作用实验,并采用液体发酵法考察真菌对铊的胞外吸附作用,实验设计了1000 mg/L、1200 mg/L和1500mg/L三种铊处理水平,借助ICP-MS检测分析样品的铊含量,以此计算吸附效率。结果表明,三种处理水平中,真菌菌株对铊的吸附效率为4.63%~16.89%,且随着环境中铊浓度的上升,菌丝体(或菌丝球)生物量明显减少,导致吸附效率的下降;真菌对常量元素如钙、钠、钾的吸附与对铊的吸附呈显著正相关。这表明真菌细胞对钙、钾的吸附方式可能与对铊的吸附方式类似。     

江西临川地区相山铀矿田构造应力场分析

相山铀矿田是中国最大的、与火成岩有关的中低温热液型矿床,断裂构造控矿特征明显。目前该矿床的后备资源出现危机,因此开展矿田构造研究,为深部及其外围找矿提供科学指导迫在眉睫。在野外观测分析和节理、擦痕实地测量的基础上,利用构造解析法、共轭剪节理分析法、断层擦痕反演模拟法及X光岩组法等,通过吴氏网投图分析和计算机的反演计算,确定了相山铀矿田多期次构造活动的变形特征及其主应力方向;并根据构造变形叠加关系及其成岩时代的确定,推断了应力作用的期次和时代。为此,将相山铀矿田的构造应力场划分为3期6个阶段,包括：成矿前的基底变形和早期火山活动阶段,早期矿化蚀变和第一、第二主成矿阶段,及其成矿期后阶段,矿体局部被错断;并深入分析了不同阶段构造活动及其铀成矿特征,探讨了区域构造应力场的演变与铀成矿作用关系,认为两者具有一致性特征,进而指出了区域富大矿体产出的有利构造部位。     

广东惠来地区早—中侏罗世桥源组海平面相对升降及构造背景的元素地球化学证据

惠来葵潭地区早—中侏罗世桥源组以海相和过渡相沉积为主。对样品进行全岩分析和ICP-MS微量元素分析,常量、微量元素及其比值反映的古盐度高低与古水深的深浅变化受海平面变化升降影响,具正相关。利用反映古盐度和古水深的m值、Sr/Ba、Ca/Mg、B/Ga和Rb/K曲线编制了桥源组海平面相对变化曲线。桥源组显示2次海侵的沉积旋回,海侵发生在桥源组中下部和中上部时期。对样品进行ICP-MS稀土元素分析和砂岩矿物成分分析,根据稀土元素分布模式图和La/Yb-∑REE源岩判别图解判断,桥源组源岩主要来自上地壳的沉积岩、玄武岩和花岗岩。根据Dickinson图解、Zr-Th、La-Th-Sc、Th-Co-Zr/10判别图解和稀土元素特征值综合分析,构造背景为弧后挤压盆地,具有大陆岛弧的特性,但少有被动大陆边缘成分。物源来自于火山弧造山带。     

http://www.sciencedirect.com/science/article/pii/S1674987111000752

A series of environmentalegeological problems have been caused by over-exploitation of deep groundwater (i.e., confined aquifer water) in the North China Plain. In order to better understand the status of deep groundwater over-exploitation and the resultant environmentalegeological problems on a regional scale, the over-exploitation of groundwater has been assessed by way of the groundwater exploitation potential coefficient (i.e., the ratio of exploitable amount of deep groundwater to current exploitation), cumulative land subsidence, and long-term average lowering rate of the groundwater table. There is a good correlation among the results calculated by the different methods. On a regional scale, deep groundwater has been over-exploited and there is no further exploitation potential under the current conditions. The groundwater exploitation degree index takes the exploitation in 2003 as the reference for the calculations, so the results mainly reflect the degree of current groundwater exploitation. The results of over-exploitation of deep groundwater obtained by land subsidence data and long-term average rate of depression of the water table mainly reflect environmentalegeological problems caused by exploitation of deep groundwater.     

长牡蛎基因组微卫星引物的开发和特性描述

长牡蛎于20世纪80年代从日本引进中国.在我国,长牡蛎已经成为重要的贝类养殖产业之一.本实验从全基因组上筛查微卫星序列,在微卫星筛查的范围、数目和类型上是传统的富集文库法开发微卫星所无法比拟的.利用基因组微卫星序列总共设计了104对引物,54对引物能扩增出目的片段,其中有34对引物显示多态性扩增,占32.7％,20对引...     

A spectral mixture model analysis of the Kuroshio variability and the water exchange between the Kuroshio and the East China Sea

For understanding more about the water exchange between the Kuroshio and the East China Sea,We studied the variability of the Kuroshio in the East China Sea(ECS) in the period of 1991 to 2008 using a three-dimensional circulation model,and calculated Kuroshio onshore volume transport in the ECS at the minimum of 0.48 Sv(1 Sv ;106 m3/s) in summer and the maximum of 1.69 Sv in winter.Based on the data of WOA05 and NCEP,The modeled result indicates that the Kuroshio transport east of Taiwan Island decreased since 2000.Lateral movements tended to be stronger at two ends of the Kuroshio in the ECS than that of the middle segment.In addition,we applied a spectral mixture model(SMM) to determine the exchange zone between the Kuroshio and the shelf water of the ECS.The result reveals a significantly negative correlation(coefficient of-0.78) between the area of exchange zone and the Kuroshio onshore transport at 200 m isobath in the ECS.This conclusion brings a new view for the water exchange between the Kuroshio and the East China Sea.Additional to annual and semi-annual signals,intra-seasonal signal of probably the Pacific origin may trigger the events of Kuroshio intrusion and exchange in the ECS.