ICT对城中村居民居住和就业迁移空间的影响——以北京5个城中村调查为例

近年来中国以互联网技术为核心的信息通讯技术(ICT)发展迅速,对居民的社会经济活动、生活方式等产生了深刻影响。本文利用问卷调查、微信访谈等方式调查了北京5个典型城中村,利用多元无序多分类logistic回归模型验证信息渠道对城中村居民居住和迁移空间的影响,结果表明：城中村住房市场非正规化从信息源头切断了居民通过互联网获取住房信息的渠道,加上城中村居民选择新住所具有就业导向和以地缘—血缘为纽带聚集的特征,信息渠道对城中村居民的居住迁移距离没有显著影响;受“就业锚点”、“距离衰减定律”和非正规就业影响,信息渠道对城中村居民近距离就业迁移也没有显著影响,但在更大空间范围内,城中村居民能通过招聘网站、社交网络等网络渠道获取就业信息,ICT的发展丰富了他们的信息获取渠道,扩大了就业空间选择,一定程度上减轻了时空制约。本文加深了关于ICT对居民日常活动空间影响、技术进步与社会平等关系的理解,丰富了居民时空间行为研究。     

Exploring the potential of circular economy to mitigate pressures on biodiversity

The effects of circular economy on biodiversity are poorly understood. This study provides observations on approaches for assessing circular economy and illustrates, with a Finnish case study, the potential of circular economy to mitigate pressures on biodiversity. The case study focuses on the construction and real estate sectors, as well as the forest industry. The findings imply that circular economy actions that reduce the extraction of virgin raw materials and relieve land use pressures are effective. Improving material efficiency, increasing the cascading use of wood, and optimizing the use and reuse of materials and products, as well as extending the lifetime of buildings and optimizing space use, have good potential for mitigating pressures on biodiversity in Finland. However, as forest utilization has a major impact on Finnish biodiversity, certain actions that possibly increase the use of forest resources (e.g., replacing fossil-based, concrete, or steel materials with wood-based solutions) may impair biodiversity if biodiversity-enhancing forest management practices are not utilized. Assessing the biodiversity impacts of circular economy is challenging, and the need for further research and the development of indicators and assessment methods is clear.     

Constructing the adaptation economy: Climate resilient development and the economization of vulnerability

Climate resilient development is emerging as a global policy strategy that integrates climate adaptation and mitigation into sustainable development decisions. For the Caribbean small island developing state (SIDS) of Antigua and Barbuda, the national government is pursuing climate resilient development through multilateral climate funds to protect economic growth from climate and weather-related disasters. Critical adaptation literature argues that interpreting climate vulnerability through an economic growth lens prioritizes economic solutions over other development concerns, which can further the uneven distribution of climate vulnerability and risk. Despite revealing the consequences of market-based climate actions, research has yet to fully understand the economization of vulnerability, which describes the political techniques that render and reconfigure vulnerability in calculated ways. By tracing the discursive interactions between multilateral climate financial institutions and the Antigua and Barbuda national government, this paper empirically examines how vulnerability is economized through climate resilient development. Findings identify the construction of ‘adaptation economies’ in watershed areas, which are economies that can capitalize upon climate challenges within areas of highest vulnerability through fee-for-climate services. The results illustrate that economic growth rationalities characterize climate vulnerability problematizations, which incentivize solutions that enforce the economic development of areas with the highest disaster impacts. Based on these findings, this study emphasizes a need to critically evaluate national actor efforts to re-organize development under climate financing rationales, and its vulnerability-inducing effects.     

Weapons of the vulnerable? A review of popular resistance to climate adaptation

Climate adaptation is not a neutral or apolitical process, but one that ignites social resistance. Government responses to risks of floods, droughts, or hurricanes – even those using a language of participation – might follow historical development pathways, strive to maintain the status quo, and directly or indirectly serve elite interests. Little attention has been paid to how people defy or resist top-down adaptation processes, overtly or covertly, in particular cultural, historical, and legal contexts. Drawing on sociological thought on popular resistance, this paper systematises research on people’s resistance to climate adaptation by scrutinising the sites, repertoires, and consequences of such resistance. We identified overt and covert resistance in 56 scientific adaptation articles, which concentrated on 5 ‘sites’ of resistance: Rural livelihoods, Urban informal settlements, Islands, First Nations, and Institutional landscapes. The findings imply that resistance to adaptation occurs globally, and not least in the context of relocation processes and participatory adaptation. We show how a resistance lens can help understand contemporary political behaviours, shed light on dynamic and compound vulnerability, and’unlock’ more context-sensitive and even transformative adaptation. Meanwhile, resistance and popular movements are not only progressive, and there might be conceptual barriers to moving from resistance to transformation or reconciling resistance with actions by or with the state.     

Comparison of Microphysical Characteristics of Warm-sector, Frontal and Shearline Heavy Rainfall During the Pre-summer Rainy Season in South China

Warm-sector heavy rainfall (WR), shear-line heavy rainfall (SR), and frontal heavy rainfall (FR) are three types of rainfall that frequently occur during the pre-summer rainy season in south China. In this research, we investigated the differences in microphysical characteristics of heavy rainfall events during the period of 10-15 May 2022 based on the combined observations from 11 S-band polarimetric radars in south China. The conclusions are as follows: (1) WR has the highest radar echo top height, the strongest radar echo at all altitudes, the highest lightning density, and the most active ice-phase process, which suggests that the convection is the most vigorous in the WR, moderate in the FR, and the weakest in the SR. (2) Three types of rainfall are all marine-type precipitation, the massweighted mean diameter (Dm, mm) and the intercept parameter (Nw, mm-1 m-3 ) of the raindrops in the WR are the largest. (3) The WR possesses the highest proportion of graupel compared with the FR and SR, and stronger updrafts and more abundant water vapor supply may lead to larger raindrops during the melting and collision-coalescence processes. (4) Over all the heights, liquid and ice water content in the WR are higher than those in the SR and FR, the ratio of ice to liquid water content in the WR is as high as 27% when ZH exceeds 50 dBZ, definitely higher than that in the SR and FR, indicating that the active ice-phase process existing in the WR is conducive to the formation of heavy rainfall.     

长江经济带城乡一体化对能源效率的空间效应分析

城乡一体化作为新的经济增长动能,是建设高效的能源经济体系、平衡经济社会发展与生态环境保护的关键性途径。因此城乡一体化对能源效率的效应分析成为促进经济社会可持续发展的重要课题。本文以长江经济带各省市为研究对象,采用DEA测度了考虑非期望产出的能源效率值,并分析其时空上的分异特征,通过构建经济、社会和基础设施3个维度的综合指标体系评价城乡一体化水平,以此为基础运用Moran's I指数确定了能源效率、城乡一体化水平及其他影响因素的空间相关性,最后运用混合地理加权回归估计城乡一体化及3个控制变量的回归参数值并作空间效应分析。得出结论:① 从空间相关性分析来看,长江经济带的城乡一体化发展水平对能源效率具有正向作用,同时经济发展水平和产业结构也对能源效率有正向影响,而技术进步则在一定条件下与能源效率呈负相关关系;② 从回归系数的估计值来看,城乡一体化对能源效率的影响程度要小于技术进步和产业结构,而经济发展水平对能源效率的影响程度最小;③ 城乡一体化水平对能源效率的正向影响程度随着能源效率的上升呈现出先上升后下降的趋势,并且其影响在空间分布上自东向西呈现出递增的特征;④ 长江经济带的能源效率呈现显著的空间相关性和空间异质性。基于此,对长江经济带推进城乡一体化进程中的能源效率提升具有重要意义。     

基于DEM的一体化山地特征要素提取

山顶点和山脊线等特征地形要素是构成地表地形及其起伏变化的基本框架,对地形在地表的空间分布具有控制作用。基于DEM研究山顶点、山脊线及其空间组合关系,是DEM地表形态特征研究的重要内容,也是衔接从地形特征分析向山峰等地貌学本源语言的途径之一。本文以四川盆地西南缘与青藏高原过渡地带的川西凉山山原为例,基于山峰-山脊线-控制范围一体化构建的算法策略,识别了山峰和山脊线及其等级、主山脊及其范围。结果表明,研究区内有主峰9座,次峰53座,平均高程2540 m;山脊线230条,其中主山脊9条,平均长度60 km;9大山系,近南北走向,平均控制面积1017 km^2。研究用模糊隶属度方法对算法所提取的主峰、主脉进行精度验证,隶属度介于0.98~1.00和0.37~0.57时提取的主峰、主脉基本吻合算法提取的结果。研究采用一体化山地特征要素提取方法,实现了各山地要素间紧密联系、总体结构与区域地貌特征相对吻合的目标;完成了由栅格单元向地理对象的转变;可以应用于协助地貌类型划分,协同区域地理规划等。     

一种灰度体素结构分割模型下的机载LiDAR 3D滤波算法

针对现有的基于机载LiDAR数据的滤波算法未能充分利用数据提供的所有信息及其所采用的数据结构表达复杂、存在信息损失等缺陷,提出了一种灰度体素结构分割模型下的机载LiDAR 3D滤波算法。算法首先以综合利用机载LiDAR数据的高程及强度信息为目的将点云数据规则化为灰度（体素内激光点的平均强度的离散化表示）体素结构,然后基于各体素间的空间连通性和灰度相似性准则,将灰度体素结构分割并标记为若干个3D连通区域,最后依据地面与其它目标的高差特性提取与其对应的3D连通区域。算法优势在于:基于体素结构设计,为3D滤波算法;综合利用了地面目标的几何及辐射特征,对比传统滤波算法可应用于更复杂的场景;滤波结果为3D地面体素形式,可直接用于创建地面3D模型。实验采用国际摄影测量与遥感协会（International Society for Photogrammetry and Remote Sensing, ISPRS）提供的不同密度的机载LiDAR基准测试数据测试了邻域尺度参数的敏感性及提出的算法的有效性,并和其他经典滤波算法做对比。定量评价的结果表明,51邻域为最佳空间邻域尺度;点云密度为0.67点/m²的数据集1的滤波平均完整率、正确率及质量分别为0.9611、0.9248及0.8934;点云密度为4点/m²的数据集2的滤波平均完整率、正确率及质量分别为0.8490、0.8531及0.7404;对比其全经典滤波算法本文算法在高密度点云数据滤波时表现更佳。     

淮南朱集西井田第二含煤段煤层对比研究

淮南朱集西井田二叠系含煤地层可划分为7个含煤段,下石盒子组为第二含煤段共含煤10层,其中4-1、402、5-1、7—8煤层为可采煤层。根据井田大量地质资料,采用标志层法、古生物法结合物性特征、煤质特征对第二含煤段可采煤层进行划分对比。4煤组中4-1、4-2均为较稳定的中厚煤层,距4-1,煤层下约13m的铝质泥岩是对比本煤组的主要依据;5煤组中5-1,煤下1m左右常见0．5m薄煤层,在39线以西常合并为一层,以此为特征区别于其他煤组：7-2为较稳定煤层,其视电阻率曲线特征呈单峰形态,长源距伽马曲线顶部靠下有一小台阶,本煤组距8煤层15m左右,间距较稳定,也可作为对比标志层;8煤层顶板富含植物化石,以常见较完整的椭圆斜羽叶及栉羊齿富集为特征,8煤层视电阻率幅值为第二含煤段最高,长源距伽马曲线常呈不对称状态,顶部曲线幅值常低于底板而明显区别于其他煤层。     

天津蓟县系雾迷山组地热流体水化学特征研究

蓟县系雾迷山组是天津地区主要开发利用的热储层之一。笔者基于区域地质资料,全面分析了天津地区蓟县系雾迷山组热储层的形成及分布特征,认为该层在天津的山区和平原区均有分布,具有分布连续稳定、沉积厚度大、裂隙发育、水质良好等特点。通过一系列的水化学资料及同位素资料分析,揭示了该热储层的水化学特征及其动态变化规律,进而阐明了地热流体的形成和运移特征。该层中的热流体其水化学类型主要受地下水径流排泄条件制约,由北部地区的HCO3-Ca·Mg型,逐步过度到南部地区的Cl·SO4-Na型,呈现由山前到盆地中心的水平分带性。