砖瓦企业综合利用河道疏浚淤泥研究

介绍了砖瓦企业利用河道疏浚淤泥替代粘土的新思路。通过取样分析和对比研究,证实这是一条值得推广应用的资源循环利用的有效途径。     

北京通州某改造区土壤中DDTs和HCHs的地球化学特征及风险评价

选取北京通州环球影城附近某改造区为研究区域,共采集15件表层土壤样品,主要分析了该地区土壤中DDTs和HCHs的空间分布地球化学特征;采集垂向样品,并分析了DDTs和HCHs在土壤垂向剖面中的分布情况。表层土壤样品中大部分的DDTs和HCHs有检出,ΣDDTs的残留量为494~19615 μg·kg-1,ΣHCHs为082~1021 μg·kg-1。土壤垂向剖面分析结果表明,DDTs部分有检出,两剖面中残留量整体随深度变化不明显,但局部出现突变现象;HCHs全部检出,两剖面中残留量整体随着深度增加不断减少。参照国家相关标准对该区土壤环境整体进行评价,初步分析通州区环球影城地区土壤中残留DDTs除个别点符合二级标准外,其余都处于一级标准,残留风险较低;土壤中残留HCHs基本符合一级标准。结合不同异构体之间含量特征及分布,认为该地区局部近期可能存在HCHs输入现象。最后,对该改造区进行了健康风险评价,结果表明该区DDTs和HCHs在致癌风险和部分非致癌风险方面影响较小。     

Spatial multi-objective land use optimization: extensions to the non-dominated sorting genetic algorithm-II

A spatial multi-objective land use optimization model defined by the acronym ‘NSGA-II-MOLU’ or the ‘non-dominated sorting genetic algorithm-II for multi-objective optimization of land use’ is proposed for searching for optimal land use scenarios which embrace multiple objectives and constraints extracted from the requirements of users, as well as providing support to the land use planning process. In this application, we took the MOLU model which was initially developed to integrate multiple objectives and coupled this with a revised version of the genetic algorithm NSGA-II which is based on specific crossover and mutation operators. The resulting NSGA-II-MOLU model is able to offer the possibility of efficiently searching over tens of thousands of solutions for trade-off sets which define non-dominated plans on the classical Pareto frontier. In this application, we chose the example of Tongzhou New Town, China, to demonstrate how the model could be employed to meet three conflicting objectives based on minimizing conversion costs, maximizing accessibility, and maximizing compatibilities between land uses. Our case study clearly shows the ability of the model to generate diversified land use planning scenarios which form the core of a land use planning support system. It also demonstrates the potential of the model to consider more complicated spatial objectives and variables with open-ended characteristics. The breakthroughs in spatial optimization that this model provides lead directly to other properties of the process in which further efficiencies in the process of optimization, more vivid visualizations, and more interactive planning support are possible. These form directions for future research.     

Identifying the Hydrochemical Characteristics, Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District, Beijing, North China

Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety, especially in aggregated population areas and economic hubs. This study focuses on the high F? and NO3? concentration groundwater in Tongzhou District, Beijing, North China. A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics, elucidate genetic mechanisms and evaluate the potential human health risks. The results of the analysis indicate: Firstly, most of the groundwater samples are characterized by Mg-HCO3 and Na-HCO3 with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471–2337 mg/L. The NO3? concentration in 38.89% groundwater samples and the F? concentration in 66.67% groundwater samples exceed the permissible limited value. Secondly, F? in groundwater originates predominantly from water-rock interactions and the fluorite dissolution, which is also regulated by cation exchange, competitive adsorption of HCO3? and an alkaline environment. Thirdly, the effect of sewage disposal and agricultural activities have a significant effect on high NO3– concentration, while the high F? concentration is less influenced by anthropogenic activity. The alkaline environment favors nitrification, thus being conducive to the production of NO3?. Finally, the health risk assessment is evaluated for different population groups. The results indicate that high NO3? and F? concentration in groundwater would have the largest threat to children’s health. The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District.     

南通通州湾工程地质条件分析

依托海陆域钻孔岩芯资料,结合南通通州湾区域地质、工程勘察资料,分析了南通通州湾基础地质条件、各土层工程地质结构特征、岩土物理力学参数与不良地质体分布情况,讨论了地面沉降、潮流通道稳定性等因素对工程建设的影响,在此基础上对南通通州湾工程地质适宜性进行评价。指出通州湾工程建设需要考虑地面沉降影响,并注意软土及易液化砂土造成的不均匀沉降和局部砂土液化;潮流通道基本保持稳定,但围堤、引桥建设可能改变局部冲淤平衡,建议加强冲淤监测。     

通州地电阻率对唐山地区中强地震的映震能力分析

基于通州地表地电阻率在1976年唐山M7.8地震前有明显前兆异常以及通州新建井下小极距地电阻率在2020年古冶M5.1地震和2021年滦州M4.3地震前出现的异常变化,从台站周边构造环境、地震特征等方面进行对比分析,认为通州台地电阻率对唐山地区中强地震的中短期映震能力比较强。同时分析结果也显示在目前观测环境条件下,井下小极距地电阻率再现了通州台地电阻率对周边地区中强地震具有较强地映震能力。     

北京市通州区地热流体水化学和同位素特征及其地热学意义

通过对北京市通州区蓟县系岩溶热储中地热流体的水化学组分、2H、18O、3H、14C、锶同位素组成的研究,论述了区域内地热系统中水的补给径流循环特征和地温分布特征.研究区内蓟县系热储中地热水的出水温度分布在35～91℃范围内,补给来源为北京市西北部或北部山区大气降水,平均补给高程为1510 m.热储中地热水年龄和热储温度...     

北京城市副中心（通州区）土地利用演变格局与模拟（英文）

北京城市副中心（通州区）承接着北京中心城区的非首都核心功能,其快速建设发展亟需对区域内土地利用演变格局的科学认识。本文分析了改革开放40年来通州区土地利用演变格局,根据土地利用历史演变特征与城市发展规划目标,结合文旅发展驱动要素,运用FLUS模型模拟城镇化加速、减速和可持续发展3种情景下2035年北京城市副中心（通州区）土地利用空间分布格局。结果表明：（1）北京城市副中心（通州区）以城镇发展建设为主,1980—2010年高速城镇化阶段形成“沿六环顺运河”的城市扩张格局,2010—2020年低速城镇化阶段用地分布稳定,通州区形成从西北至东南城乡分异、土地集约化发展格局,副中心作为通州区城镇化的典型区域具有与通州整体相似的时空演变特征;（2）到2035年,3种情景间土地利用变化幅度和空间分布存在显著差异,城镇可持续发展情景下生态用地面积与分布最优,有利于实现城市可持续发展。在与三大副中心分区规划的契合程度分析中,可持续发展情景下预测模拟与市政府发布的《北京城市副中心控制性详细规划（街区层面）（2016—2035年）》（简称《规划》）用地高度契合,但文化旅游功能区和宜居生活风貌区中模拟预测与...     

Township ecosystem health assessment based on fuzzy synthesis evaluation method: a case study of Tongzhou District, Beijing, China

With the quick development of urbanization, the urban environmental problem has broken out in rural towns. In this study, a reasonable review of the research progress in the field of urban ecosystem health was addressed. Based on the analysis of the structure-function characteristics of the compound ecosystem, the connotation of the township ecosystem health was determined. Then ecosystem health of eleven towns of Tongzhou District was evaluated. This was accomplished by first constructing an index system including three layers which were criterion, factor and index. The criterion layer contained five elements including vigor, organization structure, resilience, ecosystem service function and population health. The indicators amounted in the aggregate to twenty-two. Then the health assessment of the study area was carried out using the fuzzy synthesis evaluation method. The evaluation results were analyzed by GIS techniques. Comprehensive analysis for integral health has shown that eight towns are in sub-healthy conditions, and the other three towns of Songzhuang, Xiji and Yongledian are healthy.     

基于四维驱动力的农村居民点整理模式分析——以北京市通州区为例

利用北京市最新土地调查数据和GIS工具, 描述通州区农村居民的用地现状、空间分布和特征。(1)依据规划边界将通州农村居民点划分为圈内、环内、环外三类, 圈内农村居民点面积50.30km² (121个行政村),占总面积的30.62%;环内居民点面积19.35km² (57个行政村),占11.78%;环外农村居民点面积94.63km² (277个行政村),占57.60%.(2)不同类型农村居民点的驱动力不同, 圈内农村居民点主要是经济驱动力和社会驱动力, 环内农村居民点主要是制度驱动力和环境驱动力, 环外的农村居民点主要是社会驱动力和生态驱动力。(3)圈内居民点整理方向是实现城镇化, 应采用土地一级开发模式, 发展城市二三产业;环内居民点整理方向是改善生态环境, 发展特色产业, 适宜采取城乡一体化综合开发模式;环外居民点整理方向是增加农业用地, 减少耕地占用, 适宜采用乡村整治模式。农村居民点整理需要以驱动力为基础, 结合空间特征采取差异化的整理模式。