Urban Ecological Management Research Articles

Key indicators of high-quality urbanization affecting eco-environmental quality in emerging urban agglomerations: Accounting for the importance variation and spatiotemporal heterogeneity

As the basis of social sustainable development, eco-environmental quality (EEQ) plays an essential role in the process of high-quality urbanization (HQU). Therefore, evaluating the response mechanism of EEQ in the context of HQU will provide effective guidance for promoting sustainable development. Based on the requirements of high-quality development and the component elements of urbanization and eco-environment, the appropriate variables were selected to construct an evaluation index system between HQU and EEQ of the Shandong Peninsula urban agglomeration (SPUA) in north China. This study employed the improved coupling coordination degree (CCD) model and Moran's I to explore the dynamic mechanism and spatiotemporal distribution of coupling coordination between HQU and EEQ of the SPUA from 2001 to 2020. Meanwhile, the random forest model and the geographically and temporally weighted regression model were used to further investigate the variation in importance and spatiotemporal heterogeneity of the HQU indicators affecting EEQ. This study found that the CCD between HQU and EEQ followed a continuous upward trend in the SPUA from 2001 to 2020, which was much higher in eastern developed cities with a spatial dependency of high-high clustering. Due to the irreplaceability of energy in residents' lives, per capita energy consumption was found to be the most important impact indicator on EEQ. Population density achieved the fastest growth in importance over the study period, and the spatial indicators exhibited greater importance in the west of the SPUA. Furthermore, significant spatiotemporal differences were identified in the effects of HQU indicators on EEQ. HQU was more conducive to an improvement of EEQ in the eastern coastal SPUA. These findings could provide guidance for policy makers to adopt scientific measures in rational urban planning and ecological management of urban agglomerations in developing countries.

Indicator based assessment of urban ecological security pattern in Kolkata metropolitan area, India

In developing countries, the ecological problem in urban areas has emerged as one of the serious challenges due to rapid urbanization, industrialization and climate change. The assessment of urban ecological security (UES) provides an effective spatial approach for sustainable urban ecological planning and management. But, in the Indian context, the assessment of UES remains still unexplored. This study aims to construct a UES index (UESI) in Kolkata Metropolitan Area (KMA), India, that can be helpful for ecological sustainability. For the development of UESI, a total of 14 indices were taken into account under four major sun-indexes (human activity index or HAI, urban surface ecological status or USES, ecological health index or EHI and urbanness index or UI). Spearman correlation analysis and ordinary least square (OLS) were performed to show the relationship between variables and the impact of the variables on ecological security patterns. From the result of the study, it was found that (i) about 25% and 13% of the total urban centres came under the category of the insecure and relatively insecure category (ii) Most of the areas with insecure and relatively insecure category were located around Kolkata and its surrounding areas (such as Howrah, Bidhan Nagar, Dum Dum, Rajarhat, Baranagar, North Dum Dum) (iii) there was a negative correlation of ecological security index (ESI) with HAI and (r = −0.65) UI (r = −0.91); and positive correlation with USES (r = 0.797) and EHI (r = 0.879). As per OLS, six selected variables (settlement change, population density, population growth, land surface temperature, ecosystem service value, and normalized difference built-up index) explained more than 80% variation in ecological security pattern. Thus, a creased approach has been constructed to evaluate ecological security patterns by integrating multiple index systems. The comprehensive findings of the study provide a significant quantification framework for identifying ecological security patterns, and spatial mapping will be a fundamental support to urban spatial planning.

Sustainable Innovation on Urban Landscape Construction and Ecological Water Environment Governance Process

Abstract In recent years, various cities have continued to build urban landscapes with typical characteristics, but most of the urban landscape constructions are too similar. There is even a problem that the urban landscape is not recognised by the local people, and the same is true for the problem of ecological water governance. This article aims to study the sustainable innovation of urban landscape construction and ecological water environment governance process. To this end, this article proposes fuzzy comprehensive evaluation criteria and goals, through this evaluation system to evaluate the urban landscape construction and ecological water environment management process, and at the same time design experiments to investigate. The experimental results of this paper show that the evaluation system can help improve the urban landscape construction and ecological water environment management. At the same time, the analysis results show that under this evaluation system, urban residents’ satisfaction with the urban landscape has increased by 47 %. At the same time, the effect of water treatment has also been improved, with an improvement effect of 31 %. For the actual governance process, the effect is huge.

Characterizing composition profile and diversity patterns of spontaneous urban plants across China's major cities.

Spontaneous urban plants (SUPs) constitute an important component of urban vegetation, but they have received less attention in urban biodiversity and ecological research, especially at the regional scale. We comprehensively reviewed the occurrence records of SUPs in 59 major cities across China's geographical regions. We systematically analyzed floristic composition profiles and diversity patterns of SUPs at the regional scale and explored their influencing factors. The study identified 1211 SUP species through an extensive search of existing field research studies and fieldwork. The species composition pattern of SUPs, displaying a spatial association with climatic zones, was mainly affected by climatic factors and also anthropogenic factors. At different geographic scales, the life-form characteristics revealed some patterns, with more diverse perennials at the regional scale. The abundance of SUPs and the high proportion of native species suggested that limited urban habitats can still contribute to the enrichment and accumulation of urban biodiversity. However, in the context of globalization, continual species exchanges between neighboring regions at different scales may significantly exacerbate urban-biota homogenization. In conclusion, our study provided a regional-scale case of a synoptic SUP profile. The results furnished a scientific basis for understanding the general patterns of SUPs. The findings could inform sustainable solutions for urban ecological planning and management of spontaneous nature in cities.

Spatial and temporal dynamics of habitat quality in response to socioeconomic and landscape patterns in the context of urbanization: A case in Zhengzhou City, China

With the rapid development of urbanization, the habitat quality (HQ) in urban areas has been eroded. This phenomenon is destroying the balance of ecosystems, triggering the reduction of biodiversity and the decay of ecosystem service functions. The study of the relationship between urbanization and HQ in Zhengzhou City is beneficial for the reference of sustainable urban ecological planning and management. Based on landscape classification data and socioeconomic data for three years, this study analyzes the spatial correlations between socioeconomic and landscape pattern factors and HQ, compares the dynamic changes in the explanatory power of different factors, and explores the joint effects between multiple factors. The results show that: (1) The overall value of HQ index in Zhengzhou City decreased by .10 during 2000–2020, mainly occurring in suburban areas, with a small amount of HQ improvement occurring in the core areas of ecological protection, such as mountains and river channels. (2) The spatial autocorrelation of all influencing factors with HQ increased during this period, while the negative impact from socio-economic sources was stronger than the positive impact from landscape patterns. (3) Intensive human activities lead to a single habitat type, which reduces HQ; rich landscape types and complex landscape composition can enhance HQ. Improving the connectivity of blue-green landscapes helps to attenuate the negative effects of urbanization on HQ. (4) Changes of HQ in the study area and the development of multi-factor effects on HQ are driven by the Zhengzhou Metropolitan Area Plan. Urban development policies and management can build idyllic complexes at the edge of urban development, preserving pristine blue-green patches to avoid their homogenized distribution and thus slowing the decline of HQ. The above results provide new ideas for the development of sustainable urban ecology.

Assessment of Urban Ecological Resilience and Its Influencing Factors: A Case Study of the Beijing-Tianjin-Hebei Urban Agglomeration of China

Climate change and rapid urbanization bring natural and anthropogenetic disturbance to the urban ecosystem, damaging the sustainability and resilience of cities. Evaluation of urban ecological resilience and an investigation of its impact mechanisms are of great importance to sustainable urban management. Therefore, taking the Beijing-Tianjin-Hebei Urban Agglomeration (BTHUA) region in China as a study area, this study builds an evaluation index to assess urban ecological resilience and its spatial patterns with the resilience surrogate of net primary production during 2000–2020. The evaluation index is constructed from two dimensions, including the sensitivity and adaptability of urban ecosystems, to capture the two key mechanisms of resilience, namely resistance and recovery. Resilience-influencing factors including biophysical and socio-economic variables are analyzed with the multiple linear regression model. The results show that during 2000–2020, the spatial pattern of urban ecological resilience in the BTHUA is characterized by high resilience in the northwest and relatively low resilience in the southeast. High resilience areas account for 40% of the whole region, mainly contributed by Zhangjiakou and Chengde city in Hebei Province, which is consistent with the function orientation of the BTH region in its coordinated development. Along with urbanization in this region, ecological resilience decreases with increased population and increases with GDP growth; this indicates that, although population expansion uses resources, causes pollution and reduces vegetation coverage, with economic growth and technological progress, the negative ecological impact could be mitigated, and the coordinated development of social economy and ecological environment could eventually be reached. Our findings are consistent with mainstream theories examining the ecological impact of socio-economic development such as the Environmental Kuznets Curve, Porter Hypothesis, and Ecological Modernization theories, and provide significant references for future urbanization, carbon neutrality, resilience building, and urban ecological management in China.

Discussion on the Application of Urban Ecological Environment Management in Air Pollution Control

Discussion on the Application of Urban Ecological Environment Management in Air Pollution Control

Assessment of Ecosystem Services Supply and Demand (Mis)matches for Urban Ecological Management: A Case Study in the Zhengzhou–Kaifeng–Luoyang Cities

Accurate supply and demand matching of ecosystem services (ESs) is important for managing regional ecosystems. On the basis of remote-sensing, meteorological, and socio-economic data, we mapped the supply, demand, and matching status of four ESs (i.e., water production, carbon sequestration, food supply, and soil conservation) using biophysical models and the ArcGIS spatial analysis module within the Zhengzhou–Kaifeng–Luoyang (ZKL) urban agglomeration in 2018. Four-quadrant analysis was employed to identify the spatial matching types of supply-demand relationships within the study region. The results are as follows. The supply-demand ratios of different ESs in the cell scale exhibit different spatial characteristics because of major influencing factors, including the natural environment (e.g., precipitation and temperature) and social development (e.g., urbanization level). Analysis of the supply-demand imbalances of the four ESs indicates that water production is deficient across the entire research area, whereas the whole research area’s carbon sequestration, food supply, and soil conversation are in the surplus state. Regarding the spatial matching types for supply and demand of the four ecosystem services, water production is dominated by the “low–low (low supply and low demand)” type. Carbon sequestration is dominated by the “low–low” and “high–low (high supply and low demand)” types. The “low–low” type dominates food supply and soil conservation. Due to the severity of the deficit in water production, all districts and counties in the ZKL urban agglomeration are identified as areas requiring ecological conservation, ecological restoration, or ecological improvement. Development guidance strategies and planning suggestions are proposed in different ecological areas. These policies could also be applied in other similar urban agglomerations.

Wildland urban interface of the City of Cape Town 1990–2019

AbstractWildfire affecting urban areas at the wildland urban interface (WUI) is a growing global concern, where management is important for urban residents as well as wildland vegetation. We used a socio‐ecological system perspective to investigate the interactions of urban land with a fire‐dependent wildland in South Africa’s City of Cape Town (CoCT). We examined changes in population growth, land cover change and related WUI footprint, occurrence of large fires, and related policies over time. We used Landsat data to track changes over the period 1990–2019 in the formal and informal urban and wildland footprint, census data to track changes in population, and difference normalised burn ratio and MODIS burned area product to track large fires. The urban footprint has expanded greatly and through consolidation has led to the reduction of the WUI. Furthermore, evidence points to an increase in fire suppression, even though national policies ask for wildfires to run their course where possible and appropriate. As a result of pressure from urban residents, local managers prefer short term fire suppression to long term risk reduction for urban areas and ecological management of wildland. Framing the problem as a socio‐ecological system enabled us to highlight how WUI management is a product of interaction between urban development, wildland type and policies. Our findings emphasise the point that wildland management is driven by urban residents and local municipalities, with national fire and disaster management policies not fully implemented.

重庆市生态风险预警等级划分及演化趋势模拟

PDF HTML阅读 XML下载 导出引用 引用提醒 重庆市生态风险预警等级划分及演化趋势模拟 DOI: 10.5846/stxb202108032116 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 重庆市自然科学基金杰出青年基金项目（cstc2020jcyj-jqX0004）；国家社科基金后期资助项目（20FJYB035）；教育部人文社科一般项目（20YJA790016） Classification of ecological risk warning levels and simulation of evolutionary trends in Chongqing Municipality Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:生态风险预警等级评估和演化趋势模拟，可为生态风险管理提供可靠的辅助决策。以重庆市为研究对象，基于驱动力-压力-状态-影响-响应模型，构建重庆市生态风险预警指标体系，采用正态云模型和集对分析法，定量分析重庆市生态风险时空分异特征和演化趋势。研究结果表明：（1）2013-2019年，重庆市生态风险值呈"上升-下降"的波动趋势，综合生态风险隶属于重警等级，生态风险综合值从0.295下降到0.278，生态环境逐年好转；（2）重庆市生态风险有下降、不变、先上升后降低、先降低后上升以及一直升高5种演化趋势，分别占比39%、16%、5%、21%、24%；（3）重庆市生态风险转移分为两个方向，2013-2016年生态风险空间分异性增大，中警、轻警和无警风险等级不断向东北、东南和西部四周分散转移；2016-2019年生态风险分布格局变化较小，重警风险区在东部聚集；（4）演化趋势模拟结果表明，未来重庆市生态风险降低的区县有13个，占比34%，生态环境有向好发展的趋势；生态风险上升的区县有25个，占比66%，生态环境会有所恶化，但是恶化程度较低。将生态风险等级划分与预警演化趋势相结合，能为城市生态风险管理提供科学依据。 Abstract:The level assessment on the ecological risk early warning and the simulation on evolutionary trend can provide reliable auxiliary decision making for the ecological risk management. Taking into account the Driving-Pressure-State-Impact-Response model, this paper establishes an index system for ecological risk early warning to quantitatively analyze the temporal and spatial differentiation characteristics and evolution trend of ecological risk in Chongqing Municipality, using the normal cloud model and the set-pair analysis method. The results demonstrate that:(1) from 2013 to 2019, the ecological risk value of Chongqing presented a "rise-decline" fluctuation trend, and the comprehensively ecological risk was ranked as heavy warning level, while the comprehensive ecological risk value decreased from 0.295 to 0.278, denoting that the ecological environment had been improved. (2) There were five evolutionary trends of ecological risk in Chongqing:decreasing, unchanged, increasing-decreasing, decreasing-increasing and always increasing, accounting for 39%, 16%, 5%, 21% and 24% of all regions, respectively. (3) The ecological risk transferred to ward two orientations in Chongqing. From 2013 to 2016, the medium-alert, light-alert and no-alert risk areas continued to spread to the northeast, southeast and west of Chongqing, which intensified the spatial differentiation of ecological risks; whereas from 2016 to 2019, the high-alert risk areas were concentrated in the east, suggesting the little change in the ecological risk distribution pattern. (4) The simulation results of evolution trend revealed that 13 counties, accounting for 34% of all areas, would experience the declining ecological risk and subsequently improving ecological environment in Chongqing in the future; additionally 25 counties, accounting for 66%, would maintain the deterioration of ecological environment to small extent. The combination of ecological risk classification with early warning evolutionary trend can contribute a scientific basis to urban ecological risk management. 参考文献 相似文献 引证文献

Mapping urban energy–water–land nexus within a multiscale economy: A case study of four megacities in China

Energy, water, and land (EWL) are typical elements in urban food-energy-water systems. With the expansive growth of urbanization and the economy, the demands for EWL keep increasing and pose significant challenges to urban sustainability. Previous studies mostly focused on one or two elements flows through sectoral approaches while ignoring the interconnectedness of food-energy-water subsystems and the complexity of an open urban system. Here, we adopted a nexus view to track the urban EWL flows not only within local but also across regional, national, and even global supply chains from the production- and consumption-based perspectives using the environmentally extended multiscale input-output model (EE-MSIO). The four Chinese municipalities (i.e., Beijing, Tianjin, Shanghai, and Chongqing), also known as megacities, were selected as our cases. Our results revealed that all four megacities were consumption-oriented cities for EWL resources. Nearly 72%–77%, 87%–92%, and 95%–99% of the consumption-based energy, water, and land flows were sourced from outside the geographical boundaries of Beijing, Tianjin, and Shanghai, respectively. Domestic regions were the major suppliers for the four megacities. This analysis can help policy-makers to develop more effective and targeted strategies for complicated urban ecological resources management.

Distribution Characteristics and Influencing Factors of Phytoplankton Community in Harbin Urban River Network During Wet Season

In this study, 23 typical sampling points were selected from the Harbin urban river network during the wet season from June to August in 2019, including the Harbin section of the Songhua, Hejiagou, Majiagou, and Ashi rivers to study the distribution of phytoplankton communities. Characteristics and driving factors influencing the water environment were determined, and a total of 174 taxa of phytoplankton were identified. During the wet period from June to August, the composition of the phytoplankton community in the urban river network of Harbin was dominated by Diatom and Chlorophyta, which gradually shifted toward Diatom and Cyanophyta. The dominant species mainly include:Cyclotella meneghiniana Kützing, Nitzschia palea (Kützing) W.Smith, Synedra ulna (Nitzsch) Ehrenberg, Ankistrodesmus angustus Bernard, Pseudanabaena limnetica (Lemmermann) Komárek, and Cryptomonas ovata Ehrenberg. One-way crossed similarity analysis (One-way crossed ANOSIM) revealed significant differences in phytoplankton composition among different sections of the river during the study period (P<0.05). The Harbin section of the Songhua River was richer in phytoplankton than other sections. Redundancy analysis (RDA) shows that TP and pH are the main environmental factors that cause differences in the structure of the phytoplankton community in each section of the Harbin urban river network. This research aims to enrich the research on the ecological evaluation of urban river network by studying the phytoplankton community and environmental relevance of Harbin urban river network and provide a theoretical basis for future urban river network ecological monitoring, management, and restoration.

Analysis of remote sensing monitoring methods for construction land at home and abroad

This article stars from the construction land remote sensing detection at home and abroad research situation analysis, summarizes various analysis methods, using spatial information technology in the process of urban construction land scale spatial distribution of different land use types and the spatial and temporal evolution of urban ecological environment quality evaluation, simulation, scientific development and management to provide decision support for the city, at the same time can also be used for land use planning, it provides reference for ecological and environmental governance. This can improve and enhance the level of urban planning and management, guide and control the future direction of urban development reasonably, so as to promote the coordinated development of cities.

街区尺度城市内部动态度的量化——以深圳市为例

城市动态度反应城市土地利用/土地覆盖动态变化的剧烈程度，对其进行量化是理解城市景观变化和进行城市生态空间监管的基础。现有研究主要聚焦城市扩张引起的特定地类（如人工表面、植被等）的动态变化，缺乏对城市内部精细尺度上（如街区尺度）景观动态的研究。以深圳市为例，首先利用多等级道路数据划分街区，进而基于高分辨率卫星影像解译的土地覆盖数据，利用土地利用动态度和土地利用强度指数量化街区尺度城市内部动态度。研究结果表明：（1）深圳市城市内部动态度较高，2017-2018年期间，14.93%的街区发生了不同程度的变化，热点区域主要分布在南山区、宝安区、盐田区等。（2）街区的变化包括多种地类的转变，其中，林地转变为裸土最为常见，占比为12.59%。由城市更新引起的地类变化也较普遍，如其他不透水地表向裸土的转移和建筑到裸地的转变分别为6.20%、5.59%。此外，深圳市街区的土地利用强度也存在较大差异，表现为土地利用强度增加的街区多分布在城市外围，而土地利用强度降低的街区则多分布在城市内部。（3）街区动态度与街区大小之间呈现非线性关系，街区动态度随着街区面积的增大，先急剧下降，后趋于平缓。本研究揭示了深圳市城市内部街区尺度上土地覆盖的动态变化特征，可为城市规划和生态空间管理提供科学支撑。;Urban landscapes are highly dynamic. Understanding the within-city dynamics in land cover and land use is important. Previous studies have largely focused on the changes of specific land use type (impervious surface, urban vegetation etc.) resulted from urban sprawl on large or medium scales. However, research on quantifying the urban dynamics on block scale is lacking. Taking Shenzhen as a case study area, this paper aims to use the land cover thematic maps interpreted from very high-resolution remote sensing images to quantify the urban dynamics within city at street block level. The results showed that: (1) there was high dynamics at street block level in Shenzhen, which was manifested as that the blocks with dynamic changes account for 14.93%. The hotspots of degree of urban dynamics were distributed in Nanshan, Baoan and Yantian district. (2) The contribution of dynamic changes (CDC) was significantly different between different land use changes on block scale. For all blocks, the CDC of change from woodland to bare soil was the highest (12.59%). In addition, CDC of land use and land cover changes which mainly resulted from urban renewal was high. For example, CDC of changes from other impervious surface and building to bare soil were 6.20% and 5.59%, respectively. In addition, the land use intensity of different block was obviously different. The blocks with increased land-use intensity were mostly distributed in the periphery of the city, while the blocks with decreased land-use intensity were mostly distributed in the interior of the city. (3) The relationship between dynamics of block and block size was nonlinear. With the block size increasing, the dynamics of block decreased sharply and then the decreasing trend became flat. Our study revealed the characteristics of the land use dynamics at street block level in Shenzhen, and it would provide a reference for urban planning and ecological space management.

城市生态系统修复研究进展

城市生态系统是社会-经济-自然复合生态系统。城市生态系统修复的实质是协调好城市复合生态系统的自然过程、经济过程和社会过程之间的关系，促进复合生态系统的各方面协调高效可持续发展。以城市绿地、城市湿地、城市废弃地三类主要的城市生态空间为对象，论述了城市生态系统修复的研究进展，提出当前城市生态系统修复存在以人工修复技术为主、自然修复不足、机理和量化研究缺乏、理论和应用脱节、管理机制不健全、复合生态系统理论体现不足等问题。梳理了当前城市生态系统修复的研究热点，包括城市生态系统修复机理、城市生态资产与生态系统服务、城市生态系统质量和健康、问题导向的生态修复、面向人类福祉的生态修复、生态修复多学科融贯，以及新方法和新技术的应用等几个方面。提出了城市生态修复与管理的相关对策和建议，可为我国城市生态系统修复的研究和实践提供参考。;Urban ecosystem is a kind of complex social-economic-natural ecosystem. The essence of urban ecosystem restoration is to coordinate the relationship among the natural process, economic process and social process of the urban complex ecosystem, and promote the coordinated and efficient development of all aspects of the complex ecosystem. This paper takes urban green space, urban wetland, urban wasteland, three main types of urban ecological space, as the objects, and discusses the research progress of urban ecosystem restoration. Then we point out that the current urban ecosystem restoration has some questions such as too much artificial restoration and lacking of natural restoration, the lack of mechanism and quantitative research, the disconnection between theory and application, the imperfect management mechanism, and the weakness of complex ecosystem theory application, and so on. This article reviews the current research hotspots of urban ecosystem restoration, including restoration mechanism of urban ecosystem, urban ecological asset and ecosystem services, urban ecosystem quality and health, ecological restoration resulted from urban problems, ecological restoration oriented to human welfare, multidisciplinary integration of ecological restoration, and application of new methods and technologies. Finally, the paper puts forward the relevant countermeasures and suggestions of urban ecological restoration and management, which can provide references for the research and practice of urban ecosystem restoration in China.

区县生态系统健康评价方法——以东莞市各镇区为例

现有城市生态系统健康研究多集中在城市及城市群层面，未能深入探究城市内部特征。鉴于此，聚焦区县生态系统健康状况，进一步探究城市内部的健康分布特征；提出了"发展水平-服务功能-抵御干扰-自我维育"四维区县生态系统健康评价框架，并建立了相应的多层级指标体系，构建了区县生态系统健康评价模型；在分析区县生态系统健康变化过程及空间分异特征的基础上，识别区县生态系统健康的主要贡献因子。针对东莞各镇区的研究结果表明：1995-2015年间，各镇区生态系统健康状态总体趋于恶化，其中西南地区生态系统的退化比东南地区更为明显。自我维育对各镇区生态系统健康变化具有重要影响，主要瓶颈在于快速发展过程中土地资源的稀缺及较低的利用效率。对区县生态系统健康的研究可以帮助决策者了解城市生态系统复杂的内部特征，在此基础上更好地平衡区域发展、维护城市生态系统健康。;With the rapid urbanization, the urban population continues to increase, and the land use changes increasingly, which may induce the deterioration of ecosystems and cause threat to urban sustainable development. As an effective tool of systematic analysis, the concept of urban ecosystem health can be introduced to comprehensively evaluate the development status of cities and provide a systematic diagnosis for urban ecosystems. It is found that existing health studies on urban ecosystems mostly focus on the scale of cities and urban agglomerations, but few studies have concretely analyzed differences within cities, which is right important for urban ecological management. In order to further explore the characteristics of health distribution within cities, we paid attention to the ecosystem health at county scale in this paper. After analyzing the key characteristics of ecosystem health, we first proposed a new four-dimensional evaluation framework of county ecosystem health including development level-service function-resistance of disturbance-maintenance. And then we established a multi-layer evaluation index system of county ecosystem health composed of 20 indicators. The evaluation model of weighted sum was also constructed. In addition, the key contribution factors of county ecosystem health were identified based on the analysis of change of county ecosystem health and spatial differentiation features. It is indicated that the state of ecosystem health showed a common tendency of deterioration for the 32 counties of Dongguan from 1995 to 2015, while the degradation of the southwest region (e.g., Houjie and Shatian) was more serious than those of the southeast region (e.g., Huangjiang and Qingxi). Among the four dimensions of development level-service function-resistance of disturbance-maintenance, we found that maintenance has been exerting a great impact on the county ecosystem health, leading to changes of ecosystem health. It is further found that there were two main limiting factors of country ecosystem health, i.e., the scarcity of land and its low usage efficiency. To improve the urban ecosystem health level of Dongguan, it is suggested to improve the usage efficiency of land and other resources, and further adjust the development model and industrial structure. For example, we can release the land stock market by three-old transformation; promote ecological protection and especially ensure the health of water, soil and forest; make use of the location advantages of Dongguan to optimize the industrial structure of various counties. It is concluded that the study on county ecosystem health can help decision-makers better understand the complicated internal characteristics in urban ecosystems, which is useful for balancing regional development and maintaining the health of urban ecosystem.

Relationship study among soils physicochemical properties and bacterial communities in urban green space and promotion of its composition and network analysis

AbstractBacterial communities are closely related to soil physicochemical properties in urban green spaces, which also are important biological indicators in urban soil quality. However, there has been little basic research on soil bacterial composition and network analysis in different urban green space types, leading to a lack of micro‐understanding during urban green space management. Therefore, 30 soil sample sites from 0 to 40 cm were separately selected from two primary urban green space types (attached and park) in Beijing. We investigated how soil bacterial communities and networks respond to soil physicochemical properties by using high‐throughput 16S rDNA sequencing. Soil moisture content, organic matter (OM), total N (TN), available N, available K (AK), total Pb, and total Hg in park green space soils were significantly increased 1.49, 2.04, 1.78, 1.46, 1.20, 1.84, and 7.19 times relative to attached green space soils. A total of 2,238,221 sequences (440 bp) were acquired from urban green space soils. norank_c_Acidobacteria, Blastocatellaceae_Subgroup_4_, Gemmatimonadaceae, Anaerolineaceae, and Nitrosomonadaceae were the major bacterial families, and soil OM (36.6%, P = .01) and TN (34.6%, P = .01) were significantly (P &lt; .01) positively correlated with bacterial communities at the family level in urban green soils. Through network analysis, we determined that Actinobacteria was the core microorganism in parks and attached green space soils, but taxonomic groups in park green space soils tended to be more modular and more closely connected. Therefore, we should pay more attention to promoting development of soil nutrients in urban green spaces, especially attached green spaces. Our results provide scientific guidance for urban green space ecological environmental management.

Assessing of Urban Vegetation Biomass in Combination with LiDAR and High-resolution Remote Sensing Images

ABSTRACT The urban vegetation ecosystem is a vegetation ecosystem that is deeply influenced by human beings. The rapid urbanization process brings a great influence on the growth environment of urban vegetation. Urban vegetation has a certain mitigating effect on the urbanization process. It is irreplaceable by other urban ecosystems in functions such as maintaining atmospheric carbon–oxygen balance, reducing heat island effects, purifying, and beautifying the urban environment. At present, the estimation of aboveground biomass (AGB) mainly focuses on the original forest, grassland, desertification vegetation and crops, and the data sources are mostly medium- and low-resolution data such as Land Remote-Sensing Satellite Thematic Map (Landsat TM), Enhanced Thematic Mapper Plus (ETM+), and Moderate Resolution Imaging Spectroradiometer (MODIS). Compared with the research objects such as forest and grassland, urban vegetation has higher heterogeneity of underlying surface within the city scope, and there are more mixed pixels of medium- and low-resolution data. Therefore, high-resolution data are needed for classification and estimation. This study uses Light Detection and Ranging (LiDAR) data to expand the sample size, combines high-resolution image data to classify urban vegetation areas, and quantitatively estimates and inverts biomass. The spatial and temporal variation of urban vegetation biomass was analysed by comparing the inversion accuracy of five different models and the advantages and disadvantages of the research models. The research results show that: (1) In the absence of urban forest sample points, the biomass background data are expanded with the help of LiDAR data and more data is provided for further inversion; (2) Through five model method comparison experiments, the optimal method for estimation is based on the Random Forest (RF) model; (3) Analysed the changes of urban vegetation in the study area in the past 10 years, the development of different types of urban vegetation has experienced a trend of increasing first and then decreasing. Due to the high heterogeneity of features in urban areas, this study improved the inversion accuracy of estimating urban vegetation biomass by classification, and provided reference value and the basis for urban ecological management and regional planning.

Comparative analysis of urban ecological management models incorporating low-carbon transformation

Global climate change, rapid urbanization, and drastic economic development pose many threats and challenges to humanity, increasing the necessity for sustainable human development, urban ecological management, and low-carbon transformation. The current studies on urban management model are relatively scattered, while most of them focus on one-dimensional and problem-oriented measures. Firstly, we review the history of urban ecological management's development, including four stages, i.e., the germination, transitional, formative, and prosperity stage, and summarize the concepts related to eco-cities. Then, we present a comparative analysis of the typical urban ecological management models worldwide, with a focus on Singapore's garden city, Japan's zero-waste city, Britain's low-carbon city, Brazil's green state capital, Australia's eco-city, Finland's eco-city development projects, and the United States' comprehensive management. Three other typical models from Sweden, Germany, and Denmark are presented. The experiences and lessons from these urban ecological management models are further discussed. Finally, a new and comprehensive management framework is proposed, incorporating the five perspectives of urban planning, industrial transformation, organizational model, environmental protection, and institution system. The framework can provide a scientific basis for the refinement of urban ecological mangement. All the analysis and conclusions will contribute to the academic research and practical operations regarding low-carbon transformation and regional sustainable development.

A Spatiotemporal Analysis of the Effects of Urbanization’s Socio-Economic Factors on Landscape Patterns Considering Operational Scales

Landscape patterns are significantly affected during the urbanization process. Identifying the spatiotemporal impacts of urbanization’s socio-economic factors on landscape patterns is very important and can provide scientific evidence to support urban ecological management and guide managers to establish appropriate sustainability policies. This article applies multiscale geographically weighted regression (MGWR) to reveal the relationships between landscape patterns and the socio-economic factors of urbanization in Shenzhen, China, from 2000 to 2015, in five-year intervals. MGWR is a powerful extension of geographically weighted regression (GWR) that can not only reveal spatial heterogeneity patterns but also measure the operational scale of covariates. The empirical results indicate that MGWR is superior to GWR. Furthermore, the changes in operational scale represented by the spatial bandwidth of MGWR in different years reflect temporal changes in the spatial relationships of given factors, which is significant information for urban studies. These multiscale relationships between landscape patterns and the socio-economic factors of urbanization, revealed via MGWR, are useful for strategic planning around urban dynamic development and land resource and ecological landscape management. The results can provide additional insight into landscape and urbanization studies from a multiscale perspective, which is important for local, regional, and global urban planning.