The 3D simulation and optimized management model of groundwater systems based on eco-environmental water demand

Through the study of mutual process between groundwater systems and eco-environmental water demand, the eco-environmental water demand is brought into groundwater systems model as the important water consumption item and unification of groundwater’s economic, environmental and ecological functions were taken into account. Based on eco-environmental water demand at Da’an in Jilin province, a three-dimensional simulation and optimized management model of groundwater systems was established. All water balance components of groundwater systems in 1998 and 1999 were simulated with this model and the best optimal exploitation scheme of groundwater systems in 2000 was determined, so that groundwater resource was efficiently utilized and good economic, ecologic and social benefits were obtained.     

中国城市地理学近期进展

中国城市地理学的兴盛时期始于70年代中期,至80年代进入历史以来最旺盛的发展时期。城市地理学主要研究城市体系、城市化、城市地域结构与具体的大小城镇。其重要的实践领域则主要通过城市规划和区域规划、国土规划。特别是70年代中期借助于我国城市规划工作的复兴,为城市地理学的发展提供了广阔的实践基础。     

Petrogenesis and tectonic setting of granite porphyry in Keyouzhongqi area,Inner Mongolia

The authors studied the geochemistry,zircon U-Pb ages,Hf isotope of the granite porphyry and its petrogenesis and tectonic setting in the studied area． The zircon U-Pb dating indicates the formation of the gran- ite porphyry is in Early Cretaceous (125． 1 ±1． 5 Ma)． The granite porphyry has high-SiO2and alkali-rich fea- tures,which belongs to high-K calc-alkaline series rocks (A/CNK = 0． 95%--1． 25%)． The analyses of trace elements show the characteristics of a swallow-shaped ＲEE distribution pattern with enrichment in LＲEEs and most of LILEs and HFSEs,depletion in Ba,Sr,Nb,P and Ti,and especially strong depletion in Eu,which indicates the granite porphyry belongs to the aluminous A-type granite． Their εHf(t)range from 5． 94 to 8． 80 with Hf two-stage model ages (TDM2) of 620 Ma to 803 Ma． Combining with the regional tectonic background, we conclude that the source of the rocks is the new crust materials accreted from depleted mantle in Neoprotero- zoic and is the product of partial melting of middle and lower crustal rocks,which may be suffered from the dual impact of the subduction of the Palaeo-Pacific Ocean and the closure of the Mongol-Okhotsk Ocean．     

泛长三角区域入境游客空间格局与意象研究

城市是游客活动的重要空间载体,把握游客在城市间流动特征是探究区域城市旅游联系、明确旅游影响区域发展的作用机制与优化未来城市旅游发展布局及策略的前提和基础。本研究借助聚类法、挖掘算法与网络分析法,以地理标记照片为研究对象,对泛长三角区域52个地级城市入境游客空间特征从分布、类型、流动、意象等视角进行分析。结果显示：依据入境游客聚集程度泛长三角区域可被划分为入境旅游核心区、次核心区与边缘区,其中,核心区与区域经济中心高度吻合,次核心区旅游资源特色突出,边缘区旅游发展潜力较高。同时,入境游客流动网络密度由中部核心区向外部边缘区逐渐降低,形成一个包含四等级的网络层级结构。且各省市区域内部入境游客分布与流动也呈现差异化特征,并与各地资源禀赋、经济水平、交通条件和服务接待水平等因素密切相关。最后,入境游客意象分析也在一定程度印证出目的地最本质的地方性特征对入境游客空间分布和流动特征的影响及作用。     

鄂尔多斯盆地泾川地区三叠系延长组烃源岩特征及其沉积环境

泾川地区位于鄂尔多斯盆地西南缘,烃源岩发育情况尚不明确。通过野外地质调查和钻井岩心观察,结合烃源岩测试及元素地球化学资料,对长10—长7烃源岩进行评价,在环境分析的基础上研究影响烃源岩发育的主要因素。结果表明：研究区延长组烃源岩以长73泥页岩为最好,有机质类型以Ⅰ型和Ⅱ1为主,TOC为 0.42%～29%;长10—长7泥岩有机质以Ⅱ2型为主,平均TOC含量低于 2%;Ro为 0.47%～1.08%,有机质基本已成熟。长10—长7烃源岩形成于温暖潮湿的环境,弱还原弱氧化的淡水介质条件,水深相对较浅。古生产力、沉积速率及水介质环境影响烃源岩发育。热水活动促进了古生物的繁盛,P、Cu含量及 P/Ti值越高,有机质 TOC含量越高。（La/Yb）N值越高,沉积速率越低,有机质越富集。Cu/Zn值越高,V/Cr值越高,Th/U值越低,水体还原性越好,有机质丰度越高。总之,热水活动提高了古生产力水平,相对较低的沉积速率有利于有机质的富集,还原性较强的水介质条件可使有机质得到良好的保存。陇县一带烃源岩因受陆源植物输入的影响,且形成环境不利,烃源岩品质相对较差。     

乌鲁木齐河灌区水资源利用及可持续管理

通过对乌鲁木齐河灌区历年供水和用水状况分析,提出了该灌区水资源可持续利用的对策,并针对城市用水逐年增加与水资源供需矛盾日益突出的形势,从水份分析入手,从水资源可持续管理的角度,提出了水资源高效利用与管理的对策 。     

关中地区全新世大暖期的土壤与气候变迁

资料表明,关中地区全新世大暖期土壤中的CaCO₃受到了明显淋溶,部分土壤的CaCO₃淀积层脱离了粘化层,发育了淋溶性土壤所特有的风化淋滤母质层;该层土壤发生了明显的化学粘化作用,并有Fe₂O₃和 Al₂O₃形成以及亚热带土壤所具有的淀积型红色光性粘土胶膜发育;粘土胶膜含量明显大于淋溶褐土而与黄棕壤接近。由此得出,全新世中期成壤作用比现今显著强,土壤应为发育弱的黄棕壤,当时气候比今明显暖湿;在全新世中期,来自东南的夏季降水气团能够较频繁地到达该区,秦岭已失去温带与亚热带气候分界线的作用,其南北两侧均为亚热带气候。     

Short-Term Benthic Recolonization after Dredging in the Harbour of Ceuta, North Africa

Abstract. The benthic recovery after dredging (area: 2625 m²) was studied in a polluted and enclosed area of the harbour of Ceuta, in which the recolonization through the water column (larvae and adult bedload transport) could be limited by the lack of renewal. The benthos was sampled at two sites (control and dredged) using a van Veen grab and adopting a BACI (Before, After, Control, Impacted) approach. Five samplings were conducted after dredging (3, 15, 30, 90, 180 days). The proportion of gravel in the sediment of the dredged site increased after dredging, while the organic matter decreased. The impact on the community was estimated at species level, using both univariate and multivariate analyses. The maximum negative effect on benthic macrofauna was a reduction by 65% for species richness (15 days after dredging) and by 75% for abundance (3 days after dredging). Between 15 and 30 days after dredging, the abundance of some species such as the molluscs Parvicardium exiguum and Retusa obtusa and the polychaete Pseudomalacoceros tridentata increased considerably in the dredged site, while typical ‘opportunistic’ species such as Capitella capitata were disfavoured by the disturbance. For this small‐scale dredging, about 6 months are required for the disturbed area to re‐establish a sediment structure and a macrobenthic community similar to the undisturbed area. Small‐patch dredging operations are proposed in harbour management whenever possible, since they allow a quick re‐adjustment of the initial sediment structure and benthic communities.     

利用小波变换进行遥感多光谱图像融合的算法及实现

在分析了小波变换的分解与重建方法后,提出了一种基于区域的图像增强算法。先提取出源图的边缘,以图像的边缘为参考,围绕边缘建立融合窗口,然后结合区域内的图像信息,应用基于窗口的融合规则进行融合处理。实验结果显示,融合后的图像综合了3幅源图像的不同特征,处理后的图像变得容易识别了。表明该方法保持了尽可能多的原始信息,算法简单,稳定性好,适合于多光谱遥感图像识别、医学成像等领域。     

莱州湾东部滨海水域第四纪沉积及古地理特征

本文通过对６个钻孔和４６１ｋｍ浅层地震剖机测量获得的测年、微古、孢粉、藻类、古地磁以及岩持征和地震反射界面等资料的综合分析，将本区第四系划分为中更新统、上更新统和全新统，对各时期的沉积进行了较详细的阐述，并对不同时期的沉积相特征和古地理环境的变化进行了初步地揭示。