Trend of <i>Cryptosporidium</i>Infection among Children below 24 Months in an Informal Urban Settlement, Kenya

Cryptosporidium infection is estimated to cause 2.9 million diarrheal cases yearly among children aged under 24 months in sub-Saharan Africa. Studies have shown long-term climatic variations can affect infectious diseases. The burden of cryptosporidiosis in rural areas of sub-Saharan Africa is well characterized. However, the trend of Cryptosporidium infection is not known, especially in informal urban settings. This study therefore sought to determine cryptosporidiosis trends, and further explore the association between year and Cryptosporidium infection among children below 24 months in Kibera urban informal settlement in Kenya. Data collected by the Kenya Medical Research Institute longitudinal study in Tabitha clinic in Kibera from 2009 to 2015 were used. At least 3000 children aged < 24 months receive free health care at the clinic. In the longitudinal study, children presenting with diarrhea were eligible for stool sample collection (n = 477), out of which 421 stool samples were tested using TaqMan™ Array Card (TAC) polymerase chain reaction panel that included a target for Cryptosporidium genus. Data for the 421 children were included in the analysis. Logistic regression was used to explore the difference between the seven years and cryptosporidiosis. Overall, the pooled data indicated that 23.5% of the children who were tested had Cryptosporidium infection, with the highest proportions of Cryptosporidium-positive cases observed in 2015 (45.2%). The logistic regression results also indicated that children who were tested in the year 2015 were more likely to have Cryptosporidium infection (OR = 3.39;95% CI: 1.44 - 7.96;p = 0.005) than those in 2009. Watery stool was also found to be an important symptom of cryptosporidiosis. There was a high prevalence of Cryptosporidium infection among young children, especially in the most recent year. Routine testing of Cryptosporidium infection using molecular methods, constant monitoring and identification of the infection sources is therefore necessary towards reducing the disease burden in the low resource settings.

Urban Settlement Spatial Analysis in Permanent Preservation Area of M’boicy Watershed River, Foz do Iguaçu City in Brazil

Irregular urban settlement increases environmental impacts, especially when these occupations occur in fragile location, as the environmental preservation areas. In these areas, also defined as Permanent Preservation Area (PPA), the presence of watersheds is common, which is the factor that increases the need of protecting them from anthropic actions. Those actions deteriorate the environment and mainly the watercourses. This research objective is to identify and estimate the environmental risks of M’Boyci watershed River PPA occupied areas by urban population. The risk analysis approach, at this PPA in Foz do Iguacu City in Brazil, is able to support public interventions in order to reestablish the PPA natural conditions. To reach this goal, it was necessary to use cartographical representation images, generated from digital orthophotos analyzed through free geographical information systems. The overlap and the contrast of geographical data related to preservation in urban areas show that urban occupation reaches almost 40% of the permanent preservation area. Complementarily, it is evidenced that the development of a risk map identifies PPA areas characterized by a greater concentration of irregular settlement, contributing to the planning process of residents, relocation actions and recovery of degraded areas.

Climate Chang Impacts on Coastal Urban Settlements in Nigeria

At present,there are substantial scientific uncertainties about the nature and magnitude of climate change impacts that might result from an effective doubling of CO2 concentrations in the atmosphere of the coastal urban settlements of Nigeria.This is because a large percentage of Nigeria’s urban population lives in coastal cities.This study examines the potential impact of climate change on the coastal cities of Lagos and Port Harcourt using the Model for the Assessment of Greenhouse Gas Induced Climate Change（Magicc-Scengen）and Geographical Infor-

ON THE RELATION BETWEEN THE EVOLUTION OF NATURAL ENVIRONMENT AND HUMAN FACTORS AND THE DEVELOPMENT OF URBAN SETTLEMENT——Take the Lanzhou Valley Basin as An Examples

Lanzhou Valley Basin is composed of two smaller diamond-shaped basins striking from NW to SE and including 6 river terraces. The lower terraces remaining even and smooth are main sites for city buildings. The main function of Lanzhou urban settlement is a ferry and transport centre. Lanzhou used to be an im-portant crossing site and post on the 'silk road',and then became a transport and trade centre in Northwest China. In the middle part of the 17th century, Lanzhou became the capital of Gansu,a new province. The development process of Lanzhou urban settlement indicates that urban settlement is a system consisting of natural environment and human society based on the former.

THE EVOLUTION OF SETTLEMENT LOCATION AND DISTRIBUTION IN URBAN-RURAL INTEGRATION

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Analyzing land use characteristics of rural settlements on the urban fringe of Liangjiang New Area, Chongqing, China

The objective of this paper is to analyze land use characteristics of rural settlements in urban fringe so as to provide references for optimizing the regional distribution of rural settlements, consolidating rural settlements, and coordinating urban-rural integrated development. The methods of spatial statistical analysis, buffer analysis, Ripley's K function, kernel density analysis based on GIS(Geographic Information System) were used to analyze the characteristics of scale, spatial differentiation and spatial patterns of the rural settlements in Liangjiang New Area in Chongqing Municipality of China. The fractal dimension formula was also developed to reflect fractal feature of the rural settlements. The results show that, the scale of rural settlements in Liangjang New Area takes on distinct characteristics of spatial differentiation along with changes in elevation, gradient, location, geohazards distribution, and the like. The fractal characteristic of rural settlements has obvious regional variations subject to the 6 factors of location in the Liangjiang New Area. Overall, the worse the terrain conditions are, the larger the fractal dimension values become. The better the locationconditions, the larger the fractal dimension values are. The spatial pattern in the township scale presents three kinds of distribution as being aggregated, uniform and random. In contract, the spatial pattern in the plaque scale displays a banding distribution from a general view with several aggregation zones centering on each town center. From the results, we can see that the characteristics of rural settlements in urban fringe are more complicated. For such kind of rural settlements in special regions, in the rural land consolidation more attention should be paid to improve the rural living environments and public services, as well as to promote the harmonious relationship between the urban and rural areas.

The Role of Private Water Vending in Nigeian Peri-Urban Informal Settlements: Implication for Policy Makers

This paper presents a study of water vending in 3 informal settlements of Yola North in Adamawa State of Nigeria. These settlements represent the fast growing urban areas often dwelling in unplanned and unsecured tenure. Access to safe water supply has great influence on the health, economic productivity and quality of life of the people. But meeting this need is one of the major challenges facing the urban communities of Nigeria today. A field survey was conducted in the area with 100 observations of households in each of the three informal settlements. These settlements are Sabongari -University village, Vinikilang and Wuro Jabbe. The survey solicited for response concerning household water source, water per capita use and household size. Findings revealed that about 92% of respondent in Sabongari-University village, 66% in Vinikilang and 87% in Wuro Jabbe depend on vended water from borehole, hand dug well as well as surface water sources which are delivered by hand pushed trucks. Owing to the absence of piped water networks in the study area, households are forced to rely on available water sources which are precursor to water borne diseases. It is advocated that the public agencies should evolve special programs for regularizing informal settlements, meaning the legalization of land tenure, layout corrections and service upgrading if service is to meet the poor informal dwellers.

Urban-Ecological Survey for Small Settlements

Climate change is not just a global problem. When ecological conditions are altered by people, local climate will also be transformed. This local climate change is particularly pronounced within urban areas. This can, for example, lead to urban heat islands, which can amount to up to 10 K in large cities. In addition to this, there is also an extensive effect on local wind fields, air pollution control as well as on an urban water balance. An area-wide confirmation of this urban climate effect is only possible through extensive and usually expensive empirical surveys or complex modelling. For this reason, studies of the urban climate are mainly carried out in large cities. However, even in small settlements local climate can have a negative impact on humans. In order to plan settlement developments which are suitable for urban climate, local conditions must first be analysed. Currently used methods cannot provide low-cost solutions which deliver sufficient findings with regards to how detailed and current the data are. The approach of gathering urban-climate-relevant indicators locally, even in small settlements, in order to identify possible problem areas, is already providing a starting point for ecological urban development. Many of these indicators only start showing an effect when used in combination with other indicators. In order to record these interdependencies and to obtain detailed and robust primary data for suggested courses of action, two different indicators must be evaluated and then illustrated e.g. in a matrix. This allows for individual sub-areas, which hold potential for a particular climatic phenomenon in settlements, to be easily and effectively visualized, and thus identified.

The Research on Determinants of Moving Labors’ Settlement in Urban Area

Based on the analysis of the factors affecting the migration of moving labor and the explanation of becoming permanent urban residents,this research takes migration mode(migration) as the dependent variable,sex(sex) ,age(age) ,monthly income(income) ,education degree(edu) ,working experiences(exp) ,social relation(relation) ,and social security(security) as the independent variables.According to the investigation of China Agricultural University in the year 2009,Logistic Binary Choice Model is used to construct the corresponding econometric model and to measure the effects of influencing factors on the selection of migration mode.Result shows that education degree,personal ability,social relation,and social security are the major influencing factors determining the peasant households becoming permanent urban residents;and human capital and social security construction are of great significance to the improvement of farmers’ income and life quality.

人居环境视野下城市更新片区开发模式探究

城市更新片区开发是我国目前城市化进程转型的重要举措。研究从人居环境的理论层面出发,思考了城市更新片区开发的相关因素,分析了片区开发规划设计的“点、线、面”的具体操作,探讨了其运作模式及城市更新政策层面的一些具体模式,进而结合我院承揽的西安灞桥区及河北沧州城市更新项目,对城市更新片区开发模式进行了相关研究,对TOD模式、POR公共资源导向型模式、产城融合型模式以及旅游资源型模式进行总结,对同类项目有一定借鉴意义。

天山北坡经济带城乡聚落格局变化与影响因素分析

以天山北坡经济带城乡聚落为研究对象,采用景观格局指数、地理信息系统(GIS)空间分析、位序-规模法等分析1980-2020年间城乡聚落格局的变化,结合地理探测器从自然、区位及社会经济因素探究城乡聚落格局的影响因素。结果表明:1980-2020年间,城乡聚落数量、规模持续扩张且趋于集聚,前20 a扩张以耕地、草地为主,后20 a以未利用地为主;城乡聚落密度变化显著,高密度区主要集中在各绿洲呈现“多核集中分布”特征,中密度区沿高密度区周围扩张,低密度区沿绿洲边缘分布并在非绿洲区有扩张;首位聚落规模发展较好,趋于位序-规模曲线,中型聚落略微发育,小型聚落数量持续减少;交通等区位因素是天山北坡城乡聚落格局的首位影响因素,社会经济因素次之,自然地理因素影响较小,各影响因素差异显著。

城市产业结构如何影响流动人口的定居意愿——基于结构方程模型的实证研究

在经济高质量发展的大背景下,产业结构转型升级正在持续进行,如何提高流动人口的定居意愿、实现以人为核心的新型城镇化是学界广泛关注的话题。然而现有针对定居意愿的研究多局限于收入、心理等个人属性,忽略了产业结构等客观因素对定居意愿的制约与塑造。通过多群组结构方程模型,从理论和实证两方面研究了城市产业结构对流动人口定居意愿的路径和机制。研究发现,个人就业质量和心理认同作为中介变量,解释了产业结构对定居意愿所产生的较强的间接影响;流动人口所从事的行业类型在该影响路径中具有显著的调节效应;不同产业的流动人口在定居意愿的影响路径上存在显著差异,第二产业群体更关注就业质量,第三产业群体则近似相同的受到心理认同和就业质量的影响。基于此,本文提出制定差异化的政策,提供符合产业需求的就业机会,增强流动人口心理认同的建设,进而推动当地的城镇化和市民化进程。

新型城镇化背景下乡村人居环境治理策略研究——以河南省信阳市为例

改善人居环境,建设美好的居住环境是新型城镇化建设的关键。本文以信阳市为例,分析了其新型城镇化的现状和人居环境建设实践,并提出加强政府的顶层设计、推进乡村基础设施建设、推动城乡融合发展、建设宜居宜业和美乡村,坚持贯彻绿色发展理念等新型城镇化背景下信阳乡村人居环境治理的措施,希望为相关部门提供参考。

城市轨道交通基坑工程变形控制值研究

[目的]设置监测项目的变形控制值,对施工安全进行控制,以确保施工期间结构自身及周边环境稳定性,是城市轨道交通工程施工非常重要的工作内容。采用明挖法时,变形控制值因所处地质条件的不同而表现出较为明显的差异,需进一步明确不同地质条件下基坑的变形控制值。[方法]以北京地铁基坑工程为研究案例,分两个区域(西部、中东部)分别收集、整理了基坑工程的监测数据。选取基坑地面沉降、围护桩顶/墙顶处沉降、围护桩顶/墙顶处水平位移、围护桩体/墙体处水平位移作为监测项目,利用统计分析方法对这四类监测项目的控制值进行深入研究,并研究了变形值与基坑设计深度H的关系,针对两个区域基坑的四类监测项目分别提出了控制建议值。[结果及结论]这四类监测项目的控制建议值为:西部区域基坑建议分别取25~40 mm和0.10%H~0.20%H、15 mm、15 mm、25~40 mm和0.10%H~0.20%H;中东部区域基坑建议分别取30~50 mm和0.15%H~0.30%H、20 mm、20 mm、30~50 mm和0.15%H~0.30%H。

中国西部旅游城镇化与人居环境的时空耦合协调性及驱动力

本文在构建旅游城镇化与人居环境耦合协调理论框架的基础上,运用耦合协调模型、空间引力模型、地理探测器等方法,实证分析2005-2019年中国西部旅游城镇化与人居环境的时空耦合协调性及驱动力。结果表明:①旅游城镇化与人居环境综合指数均值呈上升态势,旅游城镇化发展水平增速快于人居环境,但人居环境指数整体高于旅游城镇化。②旅游城镇化与人居环境耦合协调度的中级协调区域居多,2017年以后演变为高级协调,耦合协调类型逐渐由旅游产业滞后型向同步发展型转变。③旅游城镇化与人居环境耦合协调度空间趋势极不均衡,空间联系强度呈现出以宁夏–陕西–重庆–贵州为主轴的链状式空间关联格局。④耦合协调度差异是不同驱动因素共同作用的结果,国际旅游收入是主导性驱动,人均社会固定资产投资是根本性驱动,A级景区数量是原生性驱动,其中国际旅游收入与A级景区的交互影响作用解释力最强。

住房压力如何影响青年流动人口的落户意愿--基于城市公共服务水平的调节效应分析

利用2017年中国流动人口动态监测数据匹配我国284个地级市及以上城市数据,考察住房压力对青年流动人口落户意愿的影响及城市公共服务水平的调节效应。研究发现:住房压力与青年流动人口落户意愿之间呈倒U型关系;城市公共服务水平能够延缓住房压力对青年流动人口落户意愿负面影响的发生。进一步分析表明,青年流动人口户籍所处地理位置与居住证办理情况均能在不同程度上影响城市公共服务的调节效果。

离家的诱惑:县域数字普惠金融与流动人口留居意愿

文章将县域数字普惠金融指数与中国流动人口动态监测调查数据相结合,实证分析了数字普惠金融对流动人口留居意愿的影响。研究结果表明:县域数字普惠金融发展能够显著提高流动人口的留居意愿。从影响机制来看,数字普惠金融发展能够通过促进流动人口创业、就业以及提高其在流入地的收入进而促使其留居。个体异质性分析表明,数字普惠金融强化了男性、非农业户口、已婚、身体健康以及高学历的流动人口的留居意愿;地区异质性结果指出,数字普惠金融促进流动人口留居的作用在东、中、西部县区无差异,人口规模越大的县区越能发挥数字普惠金融的“留人效应”,但一线城市的区县或因生活压力较大而抑制了外来人口留居。在数字技术迅猛发展、人口结构转型以及优化劳动力配置的背景之下,文章为数字普惠金融如何促进流动人口留居提供了一定的微观证据,也为县域新型城镇化的推进提供了有益参考。

Monitoring urban land cover and vegetation change by multi-temporal remote sensing information

In order to analyze changes in human settlement in Xuzhou city during the past 20 years, changes in land cover and vegetation were investigated based on multi-temporal remote sensing Landsat TM images. We developed a hierarchical classifier system that uses different feature inputs for specific classes and conducted a classification post-processing approach to improve its accuracy. From our statistical analysis of changes in urban land cover from 1987 to 2007, we conclude that built-up land areas have obviously increased, while farmland has seen in a continuous loss due to urban growth and human activities. A NDVI difference approach was used to extract information on changes in vegetation. A false change information elimination approach was developed based on prior knowledge and statistical analysis. The areas of vegetation cover have been in continuous decline over the past 20 years, although some measures have been adopted to protect and maintain urban vegetation. Given the stability of underground coal exploitation since 1990s, urban growth has become the major driving force in vegetation loss, which is different from the vegetation change driven by coal exploitation mainly before 1990.

城市群流动人口居留意愿网络特征分析及空间模式划分

基于2017年CMDS数据,运用社会网络分析、地理空间分析方法,解析中国京津冀、长三角、珠三角、成渝、长江中游及哈长城市群的流动人口居留意愿网络空间结构差异,划分其空间模式。研究发现,城市群居留网络整体上呈不同等级的“圈层”结构,距离衰减效应显著。居留网络结构特征迥异,沿海城市群流动人口来源腹地广,京津冀和长三角集聚效应明显,流动人口居留意愿更高;珠三角城市群居留强度低,结构松散。内陆城市群吸引范围有限,居留意愿低,成渝城市群居留联系弱,内外部流动相对均衡,长江中游城市群呈现弱集聚与轻均衡特征,哈长城市群内部结构紧凑,外部联系松散。不同区位、不同规模、不同发展阶段的城市群其居留意愿网络空间格局差异明显,流动人口居留选择具有明晰的地域指向。沿海城市群应加大区域低中心性城市发展,创造更多的就业机会,以吸引人口流入;内陆城市群应优化产业结构布局,平衡人口流出与流入,避免区域人口过度流失。

局地气候分区视角下城市气候与人居环境研究进展

城市气候与人居环境交互影响。局地气候分区(Local Climate Zone, LCZ)推动了城市形态刻画与气候演变规律探索,为城市气候与人居环境研究提供了统一框架。学术界对其研究大多聚焦在城市热环境和气候风险方面,正在向多要素气候模拟和考虑社会经济因素方向发展。审查了主题、方法和主要结论,发现“局地气候分区”、“城市热岛”、“地表温度”、“管理”和“社区”出现频率最高。采用文献计量和专题分析方法,梳理并总结了2012—2023年6月LCZ城市气候与人居环境研究在LCZ制图、相互作用和适应性策略三方面的进展,并展望了未来的研究重点。结果表明,(1)全球已在超过280座城市开展了LCZ研究,LCZ全球数据集的推广扩大了研究尺度且丰富了研究内容;(2)大多研究分析了风热环境为主的气候要素在局地尺度上的时空特征,探讨产生异质性的原因及其对人居环境的作用机理,揭示了城市蓝绿空间对于优化冷却效果、防范和治理热源等缓解性策略的重要性。其中自2018年起LCZ热环境研究向多元化发展,研究区域开始出现大都市圈或城市群;(3) LCZ能够辅助识别人居环境中高度暴露和脆弱的地区,近年来的研究趋向于在气候/生态风险评估中寻找适应性策略,且更加关注易感人群和低收入者。综述将有利于LCZ框架下城市气候与人居环境研究现状和发展趋势的宏观把握,为后续研究提供思路。