用斜率和曲率湿周法推求河道最小生态需水量的比较

1 Introduction With a long term of increasing water demand by industry, agriculture and domestic use along the rivers since the 20th century all over the world, the contradiction between the rational water use and water (ecological) environmental protect…     

The Liaonan Metamorphic Core Complex： Constitution, Structure and Evolution

The Liaonan metamorphic core complex (mcc) has a three-layer structure and is constituted by five parts, i.e. a detachment fault zone, an allochthonous upper plate and an supradetachment basin above the fault zone, and highly metamorphosed rocks and intrusive rocks in the lower plate. The allochthonous upper plate is mainly of Neoproterozoic and Paleozoic rocks weakly deformed and metamorphosed in pre-Indosinan stage. Above these rocks is a small-scale supradetachment basin of Cretaceous sedimentary and volcanic rocks. The lower plate is dominated by Archean TTG gneisses with minor amount of supracrustal rocks. The Archean rocks are intruded by late Mesozoic synkinematic monzogranitic and granitic plutons. Different types of fault rocks, providing clues to the evolution of the detachment fault zone, are well-preserved in the fault zone, e.g. mylonitic gneiss, mylonites, brecciated mylonites, microbreccias and pseudotachylites. Lineations in lower plate granitic intrusions have consistent orientation that indicate uniform top-to-NW shearing along the main detachment fault zone. This also provides evidence for the synkinematic characteristics of the granitic plutons in the lower plate. Structural analysis of the different parts in the mcc and isotopic dating of plutonic rocks from the lower plate and mylonitic rocks from detachment fault zone suggest that exhumation of the mcc started with regional crustal extension due to crustal block rotation and tangential shearing. The extension triggered magma formation, upwelling and emplacement. This event ended with appearance of pseudotachylite and fault gauges formed at the uppermost crustal level. U-Pb dating of single zircon grains from granitic rocks in the lower plate gives an age of 130±5 Ma, and biotite grains from the mam detachment fault zone have 40Ar-39Ar ages of 108-119 Ma. Several aspects may provide constraints for the exhumation of the Liaonan mcc. These include regional extensional setting, cover/basement contact, temporal and spatial coupling of extension and magmatism, basin development and evolution of fault tectonites along detachment fault zone. We propose that the exhumation of the Liaonan mcc resulted from regional extension and thinning of crust or lithosphere in eastern North China, and accompanied with synkinematic intrusion of granitic plutons, formation of detachment fault zone, uplifting and exhumation of lower-plate rocks, and appearance of supradetachment basin.     

交通地理网络分析模型的实现

首先介绍了网络分析的概念,接着介绍了交通网络的基本要素,然后建立了交通网络的模型,通过确定影响交通体系中网络流的因素,实现了最优路径的选择,最后用具体的数据验证了模型的合理性。     

应用化学动力学求解裂隙-岩溶介质渗流参数

裂隙-岩溶介质渗流参数的确定问题是制约渗流计算精确度的重要因素,目前求解裂隙-岩溶介质渗透参数的方法如几何形态法、现场测试法和反馈分析法等都各有局限。笔者试图将化学动力学理论引入裂隙-岩溶介质渗流参数分析计算中,研究一种有效的适合岩溶地区裂隙岩体渗流运动特点的间接参数求解方法。工程实践证明：用水化学动力学方法求解碳酸盐岩裂隙渗流参数是可行的,它具有一定的实用价值。     

构造沉降和泥沙淤积对洞庭湖区防洪的影响

With the long-term data of the geodetic sea level measurements undertaken in the Dongting Basin and the recent sediment data of Dongting Lake, we analyze the tectonic subsidence rate of the Dongting Basin and the sedimentary rate of Dongting Lake. From the point of view of geomorphology and hydrogeology, we distinguish the two different spatial concepts between “the basin of Dongting Lake“ and “the Dongting Basin“. Then, we discuss the influences of the tectonic subsidence and the siltation on the levees and the space of storing flood. The better quality of levees is required due to the tectonic subsidence and the siltation, and the difficulties of preventing flood disasters are increasing.The space of storing flood is not affected by the tectonic subsidence, but by the siltation. At present,the sedimentary rate of Dongting Lake is higher than the tectonic subsidence rate of the Dongting Basin. The tectonic subsidence capacity of the Dongting Basin counteracts a part of sedimentary capacity, and the shrinking tendency of Dongting Lake is restrained to a certain extent, but the tectonic subsidence is harmful to the situation of preventing flood disasters in the Dongting Lake area.     

盐度和光照强度对赤潮异弯藻增长的效应

采用一次性培养的方法,研究了盐度和光照强度对赤潮异弯藻增长的效应。结果表明:赤潮异弯藻在3种光照和7个盐度梯度下均可生长。盐度对赤潮异弯藻的生长有极显著的影响(P0.01),光照强度对赤潮异弯藻的生长影响亦显著(P0.05),盐度和光照强度的交互作用无显著影响(P0.05)。不论在哪种光照下,低盐度10、15组赤潮异弯藻虽然能生长,但生长速率和最大细胞数量值均较低,随着盐度的提高,藻的生长速率和最大细胞数量值增大,但盐度增至30以后,即30~40试验组的生长速率和最大细胞数量值之间的差异不明显。而不论在哪个盐度条件下,赤潮异弯藻在3种光照强度下,均以6000lx时的藻细胞密度值最高,生长情况最好。     

图解法和矩值法所求平均粒径应用对比研究

为了更好的了解图解法和矩值法计算平均粒径的区别,增强历史资料利用率,通过分析两种方法计算原理上的差异,利用某海区沉积物样品粒度测试结果,对两种方法所得平均粒径进行对比,并利用底质参数法分析两种方法所得平均粒径对声波浅海传播影响效果。结果表明,矩值法与图解法所得平均粒径在分析声波浅海传播影响上可以相互替代。     

水利水电工程征地移民项目实物指标调查测绘

本文探讨水利水电工程征地移民项目中的实物指标调查测绘方案。基于GIS地籍数据,配合河南省高分卫星高分辨率对地观测系统省级数据与应用中心自2016年至2020年数据,使用2次750m通场的厘米级航空摄影数据和1次基于无人机平台的可见光光学倾斜摄影和激光点云成像数据,最终形成13张细化标注农作物和树木种类的亚米级彩色平面地图,4张亚米级建筑物及其他附属设施三维地图,2张厘米级建筑物及其他附属设施三维地图,形成全面控制近5年征迁地区实物评价的最终指标数据。本文个案在该数据的支持下,征迁过程迅速高效完成,虽然也经历了部分诉讼调解过程,但最终对本文个案测量数据的支持率和认同率均为100%。本文调查测绘方案对水利水电工程征地移民项目有积极意义。