Exploring the factors affecting urban ecological risk: A case from an Indian mega metropolitan region

Assessment of ecological risk (ER) is a key approach to adapting and mitigating ecological deterioration in cities of developing countries. In developing countries, the ecological landscapes such as vegetation cover, water bodies, and wetlands are highly vulnerable due to rapid urban expansion. Therefore, urban ER (UER) assessment and its drivers are crucial to guide ecological protection as well as restoration. This study aims to explore the spatiotemporal pattern of UER and the impact of urban spatial form on UER in the Kolkata Megacity Region (KMR), India. This study developed a UER index and used spatial regression models across the urban centres. The ER has been assessed at city scale as well as grid-scale (2 km × 2 km and 5 km × 5 km) from 2000 to 2020. The results showed that ER has substantially increased over the last 20 years. The urban centres with very high and high ER substantially increased, i.e. from 21.95% in 2000 to 31.70% in 2020. Kolkata and its surrounding urban centres were mostly characterized by very high and high ER. ER was influenced by spatial variables (such as land use and landscapes pattern). However, remote sensing parameters were weakly related to ER. The spatial lag model (SLM) (R² = 0.8686) was found to be better fit model than spatial error model (SEM) (R² = 0.8661) and ordinary linear regression model (OLS) (R² = 0.8641). Thus, the findings of the study can improve research and a comprehensive framework for urban ecological resources and provide a scientific basis for urban ecosystem planning and restoration. In addition to this, it will guarantee the sustainable utilization of urban ecosystems.     

资源型城市景观生态风险的时空分异:以乌海市为例

为探究大型露天煤矿开采对西北干旱荒漠区景观生态风险的影响,以及资源型城市转型背景下的时空动态,以资源衰退型的内蒙古自治区乌海市及周边县域为研究区,结合现有景观生态风险评价中的干扰度、脆弱度指标,增加受威胁指数来综合构建资源型城市景观生态风险评价框架。基于乌海市2005—2015年景观类型数据,从时间和空间上分析景观生态风险及其动态。结果显示:(1)2010—2015年景观类型之间转移相较于2005—2010年更剧烈,年变化强度分别为7.43%和3.44%,工矿用地与城市建设用地最活跃,但年增加强度减小。(2)林地、水域和湿地损失度先略增加后大幅度减小,其他土地和草地损失度呈增加趋势,工矿用地先减小后略增加;城市建设用地和工矿用地受威胁指数最大,其余类型的景观受威胁指数均有上升趋势,但其他土地、水域和湿地增加趋势逐渐减慢。(3)2005—2015年景观生态风险指数升高,空间分布总体呈西、中部高而南北低的格局,而不同等级风险区表现为低风险区由边缘向中心转移,而高风险区依托原有高风险区扩展。研究期风险区变化显著的是西部沙地高风险区,矿区东部其他土地因周围分布灌丛和草地,风险始终低于西部其他土地。根据不同风险等级中工矿用地的面积占比情况,将工矿用地占比控制在5%以内可达到控制总体景观生态风险的目的。研究为资源型城市通过合理的景观配置进行生态风险管控提供了依据。     

北京延庆世界地质公园生态系统服务价值评价和生态地质调查工作建议

保护区域生态环境是世界地质公园主要功能之一。建立世界地质公园有利于促进区域生态环境保护,促进人与自然和谐共生。研究世界地质公园的生态系统服务价值可为提升世界地质公园的生态功能提供技术支撑。基于Costanza等的全球生态系统服务价值单价模型,建立了中国生态系统服务价值单价,并以延庆世界地质公园为例,运用GlobeLand30数据和ArcGIS软件对2000—2020年间延庆世界地质公园及邻区的生态系统服务价值进行评估。近20年间延庆世界地质公园的生态系统服务总价值基本保持稳定, 2000年、2010年和2020年延庆世界地质公园园区生态系统服务价值分别为3040百万元人民币、3103百万元人民币和3086百万元人民币;在园区各类生态系统服务价值中以森林、草原和农田生态系统服务价值为主,占生态系统服务总价值的96%以上。针对园区生态系统特点,提出生态地质调查和生态保护建议：一是加强园区林分组成、林分结构、林分质量和林地土壤调查,提高森林生态系统质量;二是开展湿地地下水和水土流失监测,防止湿地进一步萎缩;三是连通妫水河流域和官厅水库水系,维护河流生态流量;四是基于系统观开展园区生态地质调查,协调开展园区山、水、林、田、湖、草等不同自然要素综合调查,提高生态系统服务总价值。五是建立跨部门、跨区域生态保护协调推进机制。     

基于RS和GIS的乌江流域生态安全度变化评价

乌江流岩溶地貌发育,水土流失、石漠化问题均较突出,生态环境极其脆弱,为了了解乌江流域生态安全状况及存在问题,文章基于RS和GIS技术,在分析流域土地利用/覆盖变化和景观格局时空变化特征基础上,从自然环境、社会经济、景观生态3方面构建生态安全度评价指标体系,将熵权法与属性识别模型相耦合,对流域41个地区进行生态安全度评价。结果显示:2000年贵州省乌江流域生态安全度属于差、较差、中等、较好的面积分别为745.8 km2、15 212.2km2、40 670.7km2、9 361.4km2,所占比重分别为1.13%、23.05%、61.63%、14.19%;2010年属于差、较差、中等、较好所占面积分别为4 330.5km2、12 254.1km2、42 804.0km2、6 591.4km2,所占比重分别为6.58%、18.57%、64.86%、9.99%;2000年和2010年乌江流域均缺少生态安全等级为好的地区,而2010年较2000年生态安全等级较差的地区面积增加,较好的面积却减少,表明流域生态环境整体呈恶化趋势;流域上游、中游地区较下游地区的生态安全状况偏差,生态本底脆弱、人地矛盾突出、水土流失、石漠化等是影响上游地区生态安全度的主要原因,中游地区受矿产资源开采及大城市人口聚集的影响,下游地区受水电资源过度开发影响。      

基于3S技术的岩溶地区城市景观生态安全评价——以贵阳市为例

基于景观生态学理论,借助多时相遥感数据与GIS空间分析技术,运用“压力-状态-响应（press-state-response,PSR）”模型,构建岩溶地区城市景观生态安全评价体系,通过空间叠加分析得到2000年和2013年贵阳市城市生态安全等级分布图,并就其空间分布规律与演化特征进行了对比分析,结果表明:2000年、2013年贵阳市城市生态安全指数均较低,2000年处于安全级别以上的值为3.04,2013年处于安全级别以上的值下降到1.78,在空间分布上呈西南向东北递增的趋势;在2000-2013年间,景观生态安全指数除湿地以外其他景观类型均呈现明显的下降趋势,其中农田恶化较为明显,湿地是唯一改善的景观类型。研究时段内贵阳市景观生态安全状况处于恶化趋势,因而建议在今后的城市规划与建设中应优化土地利用格局,以提高城市景观生态安全水平。      

基于GIS和AHP的贵阳市环城林带生态敏感性评价

贵阳市环城林带对贵阳市生态环境起着控制和调节作用。近年来,随着城市化建设的发展,环城林带遭到不同程度破坏。为了保护现存环城林带资源,文章根据贵阳市环城林带地质环境条件的调查与测试资料,选择7个生态敏感性影响因子（地层岩性、地质构造、高程、坡度、坡向、地表水域和人类活动）,采用GIS技术对各单因子的敏感性进行分区,最后利用层次分析法（AHP）和空间加权叠加技术对林带生态敏感性进行综合分区。结果表明,不敏感林区占林带总面积的4.82%,分布于研究区北部;轻度敏感区占18.01%,分布于南部、东北部及东南部;中度敏感区占42.91%,分布于东部、西部及东北部;高度敏感区占29.61%,分布于北部区域;极度敏感区占总面积的4.65%,零星分布于各林区。针对各敏感区存在的主要生态环境问题提出治理与保护对策,为预防和治理贵阳市环城林带生态环境问题提供科学依据,对今后贵阳市生态规划与建设提供科学指导。     

喀斯特生态环境风险评价——以贵州省为例

区域生态环境风险评价具有尺度大、风险源与风险受体多、空间异质性强等特点,开展区域生态环境风险研究是识别生态环境风险水平、制定防范应对策略的重要理论支撑。文章以贵州省为例,参考相对风险模型为风险评价原则,基于自然灾害成因,综合考虑区域自然及经济状况,建立贵州省喀斯特生态环境风险评价框架与指标体系,运用层次分析法及系统聚类分析法,对各评价单元的危险性、暴露性、脆弱性、防灾减灾能力进行分析,并划分了区域风险程度等级。结果表明:贵州省喀斯特生态环境风险分布与生态环境本底和社会经济发展水平相关性明显,高风险区主要分布在生态环境脆弱的高原山地、高原峡谷地区以及综合发展水平较高的贵阳中心城区,低风险区主要分布在喀斯特分布面积少、生态本底好、自然灾害较少的黔东南及黔西北地区。      

贵州喀斯特石漠化防治的国家重点生态功能区生态系统健康度评价

文章以桂黔滇喀斯特石漠化防治的国家重点生态功能区贵州区为研究对象,以2010、2015年遥感影像、基础地理信息、降水、土壤等数据资料为基础,集成3S技术和生态评估模型,对水源涵养、土壤侵蚀和石漠化进行定量和定位研究。结果表明：研究区4个亚区的水源涵养功能等级处于“中”、“高”等水平,2015年比2010年的水源涵养指数有所提高;威宁—赫章区、关岭—镇宁区和册亨—望谟区3个亚区的土壤侵蚀模数较大,水土保持功能等级处于“低”等,罗甸—平塘区的土壤侵蚀模数最低,其水土保持功能等级为“中”等;威宁—赫章区2010年中度以上石漠化比重达16.36%,2015年降为8.74%,生态系统健康度从“低”转为“中”;关岭—镇宁2010年和2015年中度以上石漠化比重分别为8.64%和4.49%,生态系统健康度从“中”转化“高”;册亨—望谟和罗甸—平塘的健康度均为“高”,2015年相比2010年均有所提升;4个亚区的石漠化恶化面积所占比重均不到1.00%,石漠化好转区域分别占27.00%、14.10%、10.24%和5.13%,石漠化得到了有效遏制。今后应继续因地制宜,恢复植被和生态系统,巩固和扩大石漠化防治成果。     

Contextualizing public art production in China: The urban sculpture planning system in Shanghai

This research examines urban sculpture production to understand how a public art (called “urban sculpture” in China) scene is produced in the country, using Shanghai as a case study. Theories of Chinese urban planning are innovatively applied. The findings generate theoretical implications for “contextualizing” public art production in geographical studies. All the chief officials in charge of urban sculpture planning in Shanghai were interviewed, and documentary analyses were conducted. The article argues that urban sculptures are conceived of as both symbolic capitals and didactic tools in the cultural policies of Shanghai. Urban sculpture planning plays an important role in coordinating and manipulating development of symbolic resources to advance urban entrepreneurialism within the ideological framework of the Communist Party’s leadership. The main features of the urban sculpture planning system of China are twofold: (1) The two-tier planning structure combines a master plan at the municipal level and detailed plans for site analysis and design guidance at the district level, all collaboratively working to create an attractive city image for urban entrepreneurialism. (2) An authoritarian style of planning system controls the contents and expression of urban sculpture within the ideological framework of urban sculpture planning.     

COVID-19 strict lockdown impact on urban air quality and atmospheric temperature in four megacities of India

COVID-19 pandemic has forced to lockdown entire India starting from 24th March 2020 to 14th April 2020 (first phase), extended up to 3rd May 2020 (second phase), and further extended up to 17th May 2020 (third phase) with limited relaxation in non-hotspot areas. This strict lockdown has severely curtailed human activity across India. Here, aerosol concentrations of particular matters (PM) i.e., PM₁₀, PM_2.5, carbon monoxide (CO), nitrogen dioxide (NO₂), sulphur dioxide (SO₂), ammonia (NH₃) and ozone (O₃), and associated temperature fluctuation in four megacities (Delhi, Mumbai, Kolkata, and Chennai) from different regions of India were investigated. In this pandemic period, air temperature of Delhi, Kolkata, Mumbai and Chennai has decreased about 3 °C, 2.5 °C, 2 °C and 2 °C respectively. Compared to previous years and pre-lockdown period, air pollutants level and aerosol concentration (?41.91%, ?37.13%, ?54.94% and ?46.79% respectively for Delhi, Mumbai, Kolkata and Chennai) in these four megacities has improved drastically during this lockdown period. Emission of PM_2.5 has experienced the highest decrease in these megacities, which directly shows the positive impact of restricted vehicular movement. Restricted emissions produce encouraging results in terms of urban air quality and temperature, which may encourage policymakers to consider it in terms of environmental sustainability.     

山东淄博城市和近郊土壤元素地球化学特征及生态风险研究

以淄博城市土壤为研究对象,应用统计学方法对土壤地球化学特征进行研究,采用单因子指数和尼梅罗综合指数法对土壤环境质量进行评价,同时采用Hakanson提出的潜在生态危害指数法对土壤重金属的潜在生态危害进行评价,并对其产生的生态环境效应进行研究。结果表明:Hg、Cd、S、Pb、Se、Org C等元素或指标在表层土壤中的含量明显大于深层,二者间相关性较差,且表层土壤存在明显碱化特征,受到不同程度人为活动影响;单因子评价Cd、Cu、Hg、Ni、Zn都出现污染,其中Cd污染面积最大,达到5.11%,综合污染评价土壤环境质量整体良好,污染土壤占9.84%,其形成可能与工业生产和人类活动有关;潜在生态危害程度最强的重金属是Hg、Cd,局部地段已经达到强、极强潜在生态危害水平,综合重金属潜在生态危害水平整体表现为中等,其轻微、中等、强、很强生态危害的比例分别为29.32%、55.02%、12.85%、2.81%,从空间分布上来看,强、很强潜在生态危害区分布与各类工业空间布局相吻合,种植的蔬菜中Cd、Pb、Zn、Hg等重金属有不同程度超标现象,需加强对土壤及农产品进行协同监测与评价,防止土壤重金属污染加重影响人体健康。     

Sustainability begins at home? An ecological exploration of sub/urban Australian community-focused housing initiatives

This paper responds to challenges made by Castree [Castree, N., 2004. Environmental issues: signals in the noise? Progress in Human Geography 28 (1), 79-90] and Sneddon [Sneddon, C., 2000. ‘Sustainability’ in ecological economics, ecology and livelihoods: a review. Progress in Human Geography 24 (4), 521-549] for human geography to clarify its contribution to environmental debates and engage with recent formulations of sustainability as informed by the ‘new ecology’. This approach focuses on resilience, functional diversity, flexibility and complexity, here used to examine housing sustainability within an industrialised sub/urban context in terms of design philosophy, ownership, management bases, community engagement and funding mechanisms. This framework highlights areas of concern for enhancing the functional diversity of housing systems, echoing recent assertions that challenges for sustainability arise more from trust and power sharing issues, than from physical design and maintenance issues. It is argued that it is precisely human geography’s place-by-place consideration of power, embeddedness, scale and politics that can lend new ecology the social relevance it requires.     

基于生态需水的石羊河北部平原生态保障技术研究

针对石羊河流域日益严峻的生态环境问题,选择干旱区生态需水计算为切入点,以变异理论为基础,利用Mann-Kendall非参数检验的方法确定石羊河北部平原区地下水位恢复的目标年,用生态功能区划方法划分生态功能区,利用达西定律、阿维里扬诺夫公式计算了地下水恢复及生态目标条件下的生态需水量,并提出了相应的生态保障措施. 结果表明：石羊河北部平原区划分为5个生态功能亚区及16个三级区,地下水位恢复的目标年份为1977年,地下水恢复到1977年的生态需水量为 55.95×10⁸~74.10×10⁸ m³,2015年和2020年生态目标条件下的生态需水分别为1.66×10⁸ m³和1.80×10⁸ m³. 考虑到地下水恢复的缓慢性和现实性,建议优先考虑设定目标条件下的植被正常生长生态需水,其次通过继续压缩人均耕地面积和灌溉定额的方式保证地下水恢复.     

基于国土空间可持续利用的生态文明与城市绿色发展

生态文明与城市绿色发展要解决的问题本质上来说是正确处理人与自然之间的关系。生态文明是建设新时代中国特色社会主义和构建人类命运共同体的战略思想。城市绿色发展是转变人类社会发展模式,实现可持续发展的战略措施。两者之间有着鲜明的时代发展耦合特征,根据发展时序和中国经济社会发展阶段性特征,分为三个发展阶段:初期理论研究与实践探索阶段、逐渐上升为国家行动与理论体系建设阶段和国家行动的全面深化与理论体系的建立阶段。在城市绿色发展过程中,人通过以土地要素为主的生态空间和以产业为主的社会经济活动对自然产生影响,使城市发展在经济系统上实现绿色增长,在自然生态系统上提高绿色财富,在社会系统上提升绿色福利。城市绿色发展的基本思路:在城市发展进程中要始终坚持生态文明的理念,全面推进城市绿色发展;坚持城市空间规划先行方针;大力推进产业结构绿色升级和发展绿色新业态;强化环境保护和生态修复;实施基础设施绿色升级改造和推进绿色基础设施建设;加快制定完善城市绿色发展政策措施。     

景观生态学在城市规划和管理中的应用

城市是典型的人工景观，空间结构上属于紧密汇聚型，功能上表现为高能流、高容量和文化上的多样性。城市景观生态研究包括城市空间结构与生态过程，城市景观风貌与城市生态建设，城市景观规划是其最直接的应用。首先论述了城市景观质量与价值评价，包括景观美学评价与景观视觉容量。城市空间结构和景观规划原则是该文论述的主题，包括城市空间布局、城市空间扩展的廊道效应以及城市绿地系统的空间结构分析；以上海和广州市的绿地系统为例进行了重点介绍，最后对于城乡交错带的景观变化进行分析，用景观格局及其动态来描述城乡交错带的城市化过程特点，介绍了上海和沈阳的典型研究。     

基于生态网络构建与优化的太仓国土空间生态保护修复关键区域诊断与识别

以江苏太仓作为研究区域,基于生态系统服务评估确定生态源地,采用最小累积阻力模型（MCR）和重力模型构建生态廊道,提出生态网络优化模式和对应管控策略。经计算和分析,提取面积30 365.46 hm2的重要生态功能区作为生态源地;识别生态源地161.46 km2,其中水域生态源50个、陆域生态源地47个;提取水域生态廊道53条、陆域生态廊道56条,且水域生态廊道相较于陆域生态廊道更为完善,连通性和稳定性更高;识别需优先保护的生态夹点25个,优先修复的生态障碍点18个。研究成果可为系统性开展国土空间生态保护修复提供借鉴和指导。     

基于地质建造的生态地质调查方法——以河北省承德市国家生态文明示范区综合地质调查为例

生态地质（学）是研究生态与地质环境相互关系及作用机理的科学。通过“承德市国家生态文明示范区综合地质调查”项目的实践，探索总结出一套适合山区、基于地质建造的生态地质调查思路和技术方法框架。按照全域背景（基准）调查—重点小流域调查—生态关键带解剖3个层次开展工作，逐步深化对承德市生态地质特征和作用规律的认知。通过全域1：25万地质建造分析与编（填）图，查明生态地质背景，划分生态地质单元，快速筛选生态资源优势区和生态环境问题区；针对筛选出的生态资源优势区和生态环境问题区，开展以小流域为单元的重点区1：5万调查，以查明优势资源特征，评价生态环境风险；开展重要地质建造典型生态关键带1：1万调查与研究，揭示生态地质系统三维结构特征和相互作用机理，为综合监测和生态系统演变趋势预测提供依据。构建了生态地质调查“需求—调查—转化”体系框架，依据生态地质调查成果，为承德市国土空间规划、生态产业发展和生态保护修复，提出了相应的地学建议。     

近20年来长江经济带生态环境变化

长江经济带发展战略实施以来,长江上、中、下游地区经济快速发展,与此同时,生态系统不可避免受到扰动,长江经济带生态环境状况面临压力,亟需开展长江经济带生态环境质量评价.本文选取2001年和2020年MODIS和Landsat遥感影像计算湿度、绿度、干度、热度4个评价指标,通过主成分分析方法计算遥感生态指数RSEI,对长江...     

Climate change and its effects on urban spaces in Chile: A summary of research carried out in the period 2000-2012

We have systematized the effects associated with climate change on urban spaces in Chile reported between 2000 and 2012. The method was based on a review of scientific articles in three databases (Scopus, Web of Knowledge and Scielo) using 32 keywords. Only 14 research papers were found related to climate change in urban spaces, most of which were case studies focused on the capital, Santiago. The main effects on urban spaces were found in four areas: (1) increase in temperature (heat islands, heat waves), (2) health problems in vulnerable populations (cardiac complications, heat stroke, and respiratory diseases), (3) increased demand for water, and (4) damage to the urban infrastructure with resulting risk to the population. In these circumstances the following measures are needed: (1) effective incorporation of the potential impacts of climate change into territorial planning instruments, (2) increased green areas to mitigate the impact of heat waves, (3) limiting of housing or public services in areas at risk, (4) encouraging the design of adaptation plans by involving the vulnerable population, and (5) implementing water conservation measures. We conclude that climate change is causing effects in urban areas that should be considered in the design and expansion of cities.     

Quantify the landscape effect and environmental sustainability of rural region planning at town scale near metropolis

The urban fringe, which can be seen as a special form of regional ecosystem with a spatial transition from urban to rural areas, has strong heterogeneity and is a typical ecologically sensitive area. The expansion of cities and the landscape effect of the changes have attracted wide attention. The primary aim of this study is to obtain an understanding of the spatial patterns of landscape conversion and the corresponding environmental sustainability. With the help of GIS and Fragstats software, the changes of landscape patterns before and after town planning were compared in An-Ding town of Beijing, of which the sustainability was also revealed based on the ecological footprint using social and economic statistic data. The results showed that the landscape pattern changed greatly during its conversion from several villages to a small town and the landscape fragmentation increased due to road construction. Meanwhile, human disturbance increased with the constructed land extension. For the gap between the ecological footprint and the biological capacity, An-Ding town ran an ecological deficit at that period, which means it was unsustainable. However, the environmental sustainability decreased after planning due to the degraded green land and forest. The results suggested that ecological management should be strengthened during the town planning period.