大连市城市生态系统发展趋势研究

在对大连市城市生态系统进行系统分析的基础上,用系统动力学和灰色系统等方法探讨了大连市城市生态系统在3种不同策略下的发展趋势,为大连市城市规划和发展提供了科学依据和对策.     

Relationship between photochemical reflectance index with multi-angle hyper-spectrum and light use efficiency in urban green-land ecosystems北大核心CSCD

Aims: Light-use efficiency (LUE) is one of critical parameters in the terrestrial ecosystem production studies. Accurate determination of LUE is very important for LUE models to simulate gross primary productivity (GPP) at regional and global scales. We used eddy covariance technique measurement and tower-based, multi-angular spectro-radiometer observations in autumn 2012 to explore the relationship between bidirectional reflectance distribution function (BRDF) corrected photochemical reflectance index (PRI) and LUE in different phenology and environment conditions in urban green-land ecosystems. Methods: Using the eddy covariance technique, we estimated the temporal changes in GPP during the autumn 2012 over Beijing Olympic Forest Park. LUE was calculated as the ratio of GPP to the difference between incoming photosynthetically active radiation (PA R) and PA R reflected from the canopy. Daily PRI values were averaged from the BRDF using semi-empirical kernel driven models. The absolute greenness index (2G-RB) was made by webcam at a constant view zenith and view azimuth angle at solar noon. The logistic function was used to fit the time series of the greenness index. The onset of phonological stages was defined as the point when the curvature reached its maximum value. Important findings: Webcamera-observed greenness index (2G-RB) showed a decreasing trend. There was a highly significant relationship between 2G-RB and air temperature (R2 = 0.60, p < 0.001). This demonstrates that air temperature is the main driving factor to determine the phenology. PRI estimated from multi-angle hyper-spectrum can estimate LUE in urban green-land ecosystems in vigorous photosynthetic period. The correlation was the strongest (R2 = 0.70, p < 0.001) in the peak photosynthetic period. PRI relates better to LUE under high temperature (>15°C) with high vapour pressure deficit (VPD) (>700 Pa) and high PAR (>300 μmol·m-2·s-1). The LUE was up-scaled to landscape/regional scales based on these relationships and phenology. It can also be used for the estimation of GPP of urban green-land with high accuracy.     

Mapping transition potential with stakeholder- and policy-driven scenarios in Rotterdam City

This paper introduces a mapping approach to identify hot- and hard-spots for sustainability transition in cities by analyzing different stakeholder- and policy-driven land-use scenarios in Rotterdam City, the Netherlands. Rotterdam's sustainability office initiated a knowledge co-production process in which visions and transition pathways for the sustainable and resilient future of Rotterdam, considering existing challenges and opportunities, were co-created. These scenarios were analyzed using a straightforward scenario approach to spatially identify, map and analyze change. By mapping change, trade-offs and synergies between different land-use options among the scenarios, this study disentangles the complexity of a stakeholder co-production process and is able to discover crucial transition areas. Furthermore, multiple urban ecosystem services were valued for each scenario, and environmental impacts could be detected for all of the different visions. The mapping approach applied is a good method to communicate the consequences of induced land-use change back to stakeholders and decision-makers and thus contributes to the visual loop of real co-design. Identifying the hot-spots of change enables attention to be drawn to the most rewarding areas for transition, and moreover, it shows areas in which different visions are not conflicting but rather cross-benefiting each other. Additionally, hard-spots or areas in which existing visions contradict each other show that careful mediation and the revision of change options might be the way to go.     

Guide of strategies for urban regeneration: A design-support tool for the Spanish context

Recent studies reveal physical, economical, and socio-technical barriers when measuring performance of sustainable urban ration projects with existing assessment tools. This reality, enlarged in the Spanish context, has revealed the need of a friendly-user and holistic tool that can assist the agents involved in the decision-making process of urban regeneration projects.This paper presents the Guide of strategies for urban regeneration; a design-support tool developed by demand of the Government of the Valencian Community (Spain). Along this paper we describe how the Guide has been designed by integrating: in first place measures of exiting urban assessment tools, secondly lesson learned coming from the application of urban assessment tools to selected and rewarded urban best practices at European level, and thirdly the opinion of regional decision-makers and urban experts. As a result, this Guide offers strategies and recommendations on a self-questioning format that makes easy its implementation by any urban planner regardless of its expertise on the topic. It is based on an open-source philosophy with a nonprofit orientation, using transparent and easy-to-understand technical criteria. It can be applied to any kind of urban fabric and proposes equal representation of the thematic categories needed to be considered during an urban regeneration project design.     

Urban green space availability in European cities

Urban green space (UGS) availability has become an increasingly important aspect of planning and research because of the importance of green spaces for the wellbeing of urban residents. Municipalities across the European Union (EU) use different indicators in this area. Some cities provide per-capita threshold values for urban green space (UGS); some have recommendations regarding the minimum distance to green space while others have no recommendations at all. In this study, we assess green space availability in 299 EU cities according to land use and a population data grid. The results show a diverse picture across the EU. Southern European cities show below-average availability values, which may be explained by their low forest and tree cover and reflect the history of cities in Southern Europe. Comparatively, the above-average availability values in Northern European cities are a result of not only their biophysical conditions and the presence of rich forestland in general but also of Northern European attitudes toward urban living that naturally value having forests close to home.This assessment is complemented by a detailed case study analysis of two European cities ⿿ Berlin, Germany and ſódź, Poland. Results showed that this approach's explanatory power depends on the data used, scale of interest, resolution of data and estimated threshold value. By comparing results using different datasets and threshold values, we discuss opportunities and limitations for developing indicators of green space availability. We conclude that UGS availability is an important indicator to navigate urban complexity to improve human health and wellbeing but is only one component of the intricate social-ecological interactions within cities.     

Comparison of phenological characteristics for several woody plants in urban climates

Phenological properties of woody species were compared between two urban climates during 1997 and 1998. The study areas were Chungdam Park, Chungdam-dong, Kangnam-gu, Seoul (the urban center, 43 species) and Namhan-sansung Area, Sansung-ri, Joongbu-myon, Kwangju Gun, Kyonggi Province (the urban periphery, 16 species). Distance between these sites was 13.5 km. The differences of budding, foliation, and flowering times (1997 versus 1998) were 10.9, 3.2, and 7.4 days, respectively. Species that budded and flowered earlier were strongly influenced by Nuttonson’s Index (Tn) of February and March, but those with later dates were only weakly influenced. Unlike for budding and flowering times, foliation time was determined by air temperature or other factors in the leaf-growing season rather than by Tn. The Tn influence over phenology was stronger in shrubs and lianas than in trees. Phenophases in Chungdam Park appeared earlier than those in the Namhansansung area. The phenological differences between the two areas were 7.3 days in budding time, 8.3 days in foliation time, and 10.2 days in flowering time in mean values, with variations among species. Based on flowering-time data, the phenological variation between the two areas was equivalent to a 2.5° latitude difference. Budding time varied the most (20 days) inZelkova serrate, compared with only 3 days forPrunus padus. Differences in foliation time ranged from 15 days (inAlnus hirsute andStyrax obassia) to 0 days (P. padus). Flowering time differences were largest (24 days) inRhododendron mucronulatum and smallest (2 days) inP. padus. One can conclude that heat pollution in the urban center in Seoul severely changed phenology, and that sensitivity to that pollution differed among plant species.     

Insect communities on experimental mugwort (Artemisia vulgaris L.) plots along an urban gradient

We studied the ability of insect herbivores and their natural enemies to colonize exposed, potted mugwort plants (Artemisia vulgaris L.) along a rural-urban gradient in 1994 in Hamburg (northern Germany). Ectophagous insects, leafmines and galls were monitored weekly from mid-May to mid-September. Endophagous insects were counted by harvesting and dissecting the stems at the end of the growing season. The rural-urban gradient was characterized by a gradient of vegetation-free areas and increasing proportion of ground covered in concrete, tarmac, paving and other impermeable surfaces surrounding the Artemisia plots, i.e. six different zones of increasing isolation. Numbers of insect species (herbivores, parasitoids and predators) decreased along the gradient from 43 to 12. Monophagous herbivores were not more affected than polyphagous herbivores, but parasitoids, especially rare species, were more strongly affected by isolation than predators. Some dominant herbivorous species were very successful colonizers and occurred in inner city sites devoid of all natural vegetation. Sometimes their abundance increased in the inner city to significantly higher densities than in the urban fringe. Isolation appeared to be the main reason for the observed patterns, since area and soil conditions were held constant in the experiment. Microclimate and pollution were considered to play a minor role. Received: 16 January 1997 / Accepted: 26 August 1997     

Assessing the urban environmental quality of mountainous cities: A case study in Chongqing,China

Despite the degradation of urban environment associated with the rapid urbanization, limited studies have examined the spatial patterns and driving factors of urban environmental quality (UEQ) in mountainous cities in China. Using a case study of Chongqing, UEQ in mountainous cities was measured in the dimensions of physical environment, built environment, and natural hazards, followed by an exploration of its spatial pattern. It was found that the UEQ has been significantly affected by the factors of pollution and dense built environment. Pollution factor was highly correlated with industrial land ratio and land surface temperature, and dense built environment factor bore close relationship with road density, impervious fraction, and floor–area ratio. Through a cluster analysis, Chongqing was classified into five UEQ clusters and their spatial distribution was found as a combined polycentric and mosaic pattern. While mountains and hill ridges, riverside banks, small hills, and streams showed high UEQ indices, valley floors exhibited low UEQ values. Polycentric urban development adapting to mountainous landscapes was believed to contributing to the extremely low UEQ in urban center and subcenters. However, polycentricity, leading to appropriate spatial match of jobs/housing, also resulted in high UEQ in the peripheries. The effects of redevelopment, relocation or suburbanization on UEQ were also discussed through four examples.     

国际城市森林研究知识图谱——基于CiteSpace V共被引分析

城市森林作为城市中重要的生态系统,对城市环境和整体生态系统的稳定性起着至关重要的作用。通过CiteSpace V软件对Web of Science核心合集中"urban forest/城市森林"的研究文献进行可视化分析,得到清晰明了的知识图谱,对国内城市森林研究有着重要的参考意义。研究表明,1）2004-2014年这10年间为国际城市森林研究的繁荣期,产生了数量最多、影响力最高的研究文献。2）国际上"urban forest/城市森林"研究的发展历程中,针对Fragmentation/破碎化的研究处于最为核心的位置,结合Wildland-urban interface/荒地-城市交界处、Water quality/水质、Outdoor recreation/户外休闲三个聚类方向,形成了国际城市森林研究的奠基位置;3）现在国际城市森林研究的热点主要集中在城市森林本体健康状态、城市森林生态服务功能、城市森林对于整体生态环境稳定性三个层次上;4）总体来说,相对于国内研究,国际上对于城市森林的研究深度、维度方面都更具优势,值得借鉴。     

贵州黔灵山公园半野生的猕猴的种群动态

科学分析动物种群增长动态,合理确定环境容量是管控城市半野生动物种群激增危害的根本途径。本文对贵州贵阳黔灵山公园半野生猕猴种群特征、种群增长、环境容纳量以及猴群对公园的危害进行了研究分析。结果表明：（1）较之野生种群,园内栖息种群密度高、猴群大。现有8个稳定猴群共计1067只[最小群：47只;最大群：226只,平均：（133±67）只],总体雌雄性比为1.33;全区种群密度约达251只/km²,但猴群主要栖息于游道及其周边,导致主分布区密度高达 2134只/km2;（2）种群增长迅速、繁殖力旺盛。自1992年以来,种群呈指数型增长（年均增长率为8.08%,增长函数为y=30.6789*exp[(x-1987)/8.7894+ 64.0193),当前种群总体年龄结构为成年猴>青年猴>幼年猴,虽青幼个体数量较成年个体少,但成年雌雄性比达到1.50,性成熟个体较多,有效种群数大,仍保持旺盛的繁殖力;（3）种群Logistic增长曲线（y=792/(1+2.8495E+183*exp-0.2104x）表明园内环境容量（K值）为792只,与该区猕猴伤人事件频率曲线进入高位平台期所对应的种群数量接近。文中还对猴群栖息对当地植物多样性造成的影响进行了调查。调查监测表明,种群过大且集中栖息导致公园内生物多样性破坏、人猴冲突、公共健康隐患等一系列问题产生,建议应通过节育、分流等相关措施,将种群数量控制在K/2即400只左右为宜。本文可为黔灵山公园猕猴保护管理及其他城市野生动物管理提供参考。