基于生态位理论的浙江省旅游城市竞争发展策略

在区域间旅游竞争日趋激烈的背景下,如何明辨竞争对手,采取科学竞争策略,是目前许多旅游城市亟待解决的问题之一。尝试运用生态位重叠理论和生态位态势理论构建了旅游城市竞争关系判断框架,并以浙江省11个旅游城市为研究对象进行了实证分析,发现这11个城市间旅游生态位重叠度都处于较高水平,彼此之间竞争压力比较大。11个旅游城市中,杭州、宁波和温州的旅游综合生态位居前三位,在旅游市场竞争中处于比较有利的地位,而舟山、湖州、衢州分别居倒数前三位,在旅游市场竞争中处于弱势的地位。在此基础上,运用生态位错位、生态位扩充等理论,针对每个城市与其他城市间的生态位重叠度和自身旅游综合生态位的大小,提出了相对应的基本竞争发展策略。     

中国城市空间形态的环境效应

中国城市需要更为紧凑的空间形态,但是城市空间紧凑性的环境效应并不十分清晰。采集城市管网设施指标、城市道路、交通设施指标、生态协同指标等建立环境因子指标集,选择标准化紧凑度指数NCI、标准化离散度指数NDIS、最大斑块面积指数LPI、景观形状指数LSI、平均形状指数SHAPE_MEAN、周长-面积分形维数PAFRAC等形态指标,运用统计分析的方法探索中国146座城市的空间形态的单因子环境效应、综合环境效应及环境效应的差异性。研究结果表明:(1)人均城市道路面积、供水管密度、排水管密度、万人拥有公交车辆、万人拥有出租车辆、人均公园绿地面积等环境因子与城市空间形态密切相关。城市紧凑度越高,城市管网系统密度越低,公共交通设施越少,人均公园绿地面积越少。城市形状越复杂,城市管网系统密度越高,公共交通投入越大,人均公园绿地面积越大。(2)综合环境因子与LSI呈中等强度的正相关(r=0.43,P0.01)。城市空间形状越复杂,城市资源环境相关设施总体投入越多。(3)在不同的紧凑及形状复杂性水平下,万人拥有公交车辆、万人拥有出租车辆、供水管道密度及综合环境因子的显著性差异再次表明城市越紧凑,交通越发达;城市形状越复杂,环境投入越多。本文研究证明了城市空间形态越紧凑、资源越是节约,紧凑型城市空间形态能够用于中国城市建设。     

基于生态位适宜度的耕地可持续利用评价

耕地可持续利用评价是土地利用研究的重要内容.基于生态位理论,从区域耕地生态系统整体性出发,提出耕地生态元和耕地生态位的概念,并在此基础上构建了耕地可持续利用生态位适宜度评价模型( Fi模型).然后,将所构建模型应用于河南省焦作市耕地可持续利用评价之中,测度了1997～2006年期间焦作市耕地可持续利用生态位适宜度Fi值.为了便于对照分析,采用限制因子模型(NFmin-i模型)和希尔伯脱空间模型(CHi模型)进行耕地可持续利用生态位适宜度NFmin-i值和CHi值的测算.测算结果表明:(1)1997～2006年期间, Fi值总体上呈递增趋势,从1997年的0.5088增加到2006年的0.6503,表明支撑焦作市耕地可持续利用的自然、经济和社会因子总体上呈良性发展趋势,即耕地可持续利用现实生态位趋于最适生态位.(2)1997～2006年期间,Fi与CHi值各年间的变化规律一致,与NFmin-i值总体变化规律一致,表明运用Fi模型进行耕地可持续利用评价具有较强的科学性和现实性.同时,Fi值有利于从综合角度表征区域耕地总体可持续利用水平.(3)利用最适生态位解释区域耕地可持续利用评价标准,以及运用n维资源(条件)生态位与最适生态位的匹配这一基本思想进行区域耕地可持续利用评价,生态意义明确,便于依据生态位适宜度值的大小及其变化制定区域耕地利用方案和措施.     

浙江乐清湾浮游动物空间生态位

基于2016年5月至2017年2月在乐清湾进行的4个航次浮游动物调查数据,计算乐清湾浮游动物优势种的优势度指数(S)、平均拥挤度(X^*)、生态位宽度(B_i)及生态位重叠值(Q_ik )。结果表明: 乐清湾海域浮游动物优势种(S＞0.02)共17种,生态位宽度值差异较大,优势度指数与生态位宽度值呈极显著正相关。浮游动物的生态位重叠值极低,Q_ik＞0.6的种对有25对。冗余分析表明,温度和盐度是影响乐清湾海域浮游动物优势种分布的重要因素,浮游动物优势种在这些环境因子上存在生态分化现象。     

内蒙古阿拉善荒漠主要啮齿动物生态位测度比较

用3种不同的生态位宽度和生态位重叠测度方法,对内蒙古阿拉善荒漠11种主要啮齿动物的生态位进行了比较研究。结果表明,子午沙鼠的生态位宽度指数最高,3种方法计算结果分别为0．842、0．723、0．516。该种在7种生境中均有分布,且以人工草地和农田的数量最高,天然草地的数量最低,对7种资源等级的利用具有一定的选择性。五趾跳鼠的次之,分别为0．751、0．722、0．513。该种在7种生境中均有分布且数量差异不大,对7种资源等级的利用具有一定的普遍性。比较3种生态位宽度指数测度方法,以Shannon．WienerIndex对荒漠区啮齿动物较为适宜。生态位重叠指数最高的啮齿动物因计算方法的不同有1-9个种对,生态位重叠指数最低的有10～11个种对。分析比较3种生态位重叠指数测度方法,以Pianka Index更适合于荒漠区啮齿动物的生态位重叠测度。     

沙坡头地区人工林植物的水分生态位适宜度分析

本文根据沙坡头水分观测站多年的土壤水分观测记录,建立了植物种生态位适宜度的数学模型,对各种固沙植物不同密度下的生态位适宜度,以及适宜度的时空变化进行了定量分析。结果表明合理的营林密度为２５００株每公顷,这时植物种的生态位适宜度最大。     

淀山湖浮游植物优势种生态位

运用改进的Levins公式和Petraitis指数测定了淀山湖浮游植物优势种的生态位宽度和生态位重叠,分析了生态位宽度、种间生态位重叠与优势种密度和优势度的相关性.结果表明： 不同时期各优势种的生态位宽度和生态位重叠不尽相同,各物种对环境因子的适应能力存在差异.根据不同季节的生态位宽度可以将淀山湖浮游植物优势种分为4类;尖尾蓝隐藻和小球藻的生态位较宽,数量较多,分布较广,能充分利用环境资源.水华暴发时期,蓝藻门各优势种与其他藻类之间的生态位重叠程度相对偏高;铜绿微囊藻的生态位变宽,而其他优势种的生态位宽度相对有所降低.各季节优势种的优势度与其生态位宽度呈显著相关,优势种密度与生态位重叠呈极显著相关.     

北部湾北部生态系统结构与功能——浮游动物空间生态位及其分化

根据2006—2007年北部湾北部海域4个航次调查资料,采用K-优势度曲线法对浮游动物种(类)群进行排序分析,运用Levins公式和Pianka指数分析了主要优势种(类)群的生态位宽度值和生态位重叠程度,并通过除趋势典范对应分析(DCCA)研究生态位分化状况。结果表明,该海区浮游动物优势种(类)群按生态位宽度值可划分为广生态位、中生态位和窄生态位三大类型。其中,广生态位的种(类)群如肥胖软箭虫、亚强次真哲水蚤、长尾类幼体等具有较强的生态适应性,生活范围较广;窄生态位的种(类)群,对环境的适应性较差,对海流和水团等环境因素的变化具有指示意义。生态位宽度能够反映种(类)群丰度季节变化,但不能反映具体丰度大小。北部湾北部全年主要优势种(类)群的生态位宽度值介于0.08—0.77之间,并且各优势种(类)群的生态位宽度差异较大,种对间生态位重叠值介于0.02—0.89之间,平均生态位重叠指数为0.45,种(类)群之间利用资源环境的互补性较强,这与海域内生境多样化并且各优势种对环境适应能力的差异存在一定联系。DCCA分析表明,影响浮游动物分布的主要因子是水深、温度和盐度,其次是叶绿素a和溶解氧。     

柴达木盆地东部荒漠植物生态位特征

以柴达木盆地东部27个典型样地的植物群落为研究对象,通过生态位宽度和生态位重叠指数计算,分析该区13种优势植物在土壤含水量、容重、有机质、pH、全盐、全氮维上的生态位特征,以期为柴达木盆地植被恢复重建和荒漠系统生态保护提供理论参考。结果表明:①13种植物在6个土壤因子上平均生态位宽度从大到小依次是:驼绒藜、琵琶柴、芨芨草、芦苇、合头草、蒿叶猪毛菜、白刺、盐爪爪、小嵩草、麻黄、沙拐枣、柽柳和梭梭,其中,驼绒藜在土壤含水量、容重和有机质上占据最高值,琵琶柴在土壤pH、全盐、全氮维上占据最高值;②生态位宽度较大的物种在生态位重叠上并不占据最高重叠值,而是处于一个中游的位置;③驼绒藜和琵琶柴在生态位宽度和生态位重叠上均占相对高的位置,对群落的建群起重要作用;④78个种对在每一个土壤因子上的生态位重叠值0.3的占总对数的比例为76%,柴达木盆地东部植物总体生态位重叠偏低,竞争较小,群落处于一个相对稳定的状态。     

瓯江流域水生植物多样性与生态位研究

根据2010-2013年调查结果,结合相关文献资料,研究了瓯江流域的水生植物多样性和物种生态位。结果表明:①瓯江流域有水生高等植物181种(含亚种、变种),隶属于41科78属,属的分布型以世界分布为主,占总属数43.59%,热带性质的属发育较温带性质充分。②30个临时样地划分了河流、沼泽、农田、沟渠、池塘、洪泛湿地等6类生境类型,单位面积物种数以洪泛湿地最高0.09 ind./m2,其次是沼泽生境0.07 ind./m2;农田和池塘生境物种多样性随流域高程降低逐渐升高,其余生境物种多样性以中游最高;优势种生活型以挺水、漂浮植物为主,沉水植物、浮叶植物重要值较低; ③挺水植物生态位宽度普遍高于其他生活型,沉水、浮叶植物生态位宽度普遍较低;相同生活型植物生态位重叠以漂浮植物间最高,以沉水植物间最低;不同生活型植物生态位重叠以挺水-浮叶植物间最高,以沉水-漂浮植物间最低;生态型多样的喜旱莲子草(Alternanthera philoxeroides)生态位宽度较大,与其他物种生态位重叠高,由此推测喜旱莲子草可能引起瓯江流域水生植物群落结构的变化,导致乡土水生植物物种多样性的降低。       

GMM-based research on environmental pollution and population migration in Anhui province,China

The urban population in Anhui province has increased rapidly in recent years. Simultaneously, society has grown more concerned with protecting the ecological environment, including controlling atmospheric pollution. As such, the relationship between urban population and the environment merits consideration. This paper examines five statistical indicators (urban population, three kinds of industrial waste, and urban green area) using the GMM method to quantitatively explore the relationship between urban population and the ecological environment in cities of Anhui province. The results show that waste gas pollution is truly positive to the emigration of population and to each area, the higher the level of average urban income, the higher the possibility of emigration after the area being polluted; effects are smallest on landscape green area. The article concludes with suggestions on how policymakers can better align the needs of a growing urban population with environmental growth.     

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.     

城市绿化对空气质量的影响研究——以中国27个省会城市为例

城市间绿化程度与空气污染比较及相关差异分析是提出城市环境管理措施的重要前提。选择全国27个主要省会城市,基于网络街景照片测定绿色指数差异,对比空气主要质量指标[空气质量指数(AQI)、细颗粒物(PM_2.5)、可吸入颗粒物(PM₁₀)、二氧化硫(SO_2)、二氧化氮(NO_2)、臭氧(O_3)、一氧化碳(CO)]的基础上,探讨了二者相关关系,旨在为提升环境质量、改善绿化水平提供基础数据。结果表明:(1)济南市和重庆市的绿色指数最高,分别达到是11.70%和11.55%,呼和浩特市和拉萨市城市绿色指数最低,在4%～5%。(2)海口市的空气质量最好,AQI为39.66,郑州市和济南市的空气质量最差,AQI年均值分别为117.34和113.93。但是不同空气指标城市排序间差异较大,比如PM_2.5、PM₁₀、NO_2以及SO_2年平均最低的城市都是海口,拉萨市年平均CO含量最低(0.55 mg·m^-3),哈尔滨市年平均O_3含量最低(77.08μg·m^-3)。(3)相关关系分析发现,增加城市的绿色程度,伴随着空气质量的改善,如沈阳、南宁、合肥等城市;但对于某些城市,则存在明显的正相关,如兰州、昆明、贵阳等城市,这意味着城市越绿伴随着空气污染的加重。尽管大量研究已经表明,城市绿色植被能够起到滞尘降低污染的作用,目前我国主要城市的空气污染程度,仅依靠城市绿化改善已经远远不够,甚至某一些城市绿色植被存在阻碍空气流通的作用。上述研究结果为科学规划城市绿化、提升空气质量提供基础数据支撑。     

中国城市生态与经济社会协同性评估

为认识城市经济社会和生态的协同特征,本研究基于城市人均绿地面积、人均GDP和人均期望寿命等构建城市生态与经济社会功能协同性指标评价体系,建立城市生态与经济社会协同性指数评价方法。通过比较中国35个典型城市的协同性指数与功能综合得分,分析了中国城市协同性特征,并按照城市规模、行政区类型分析城市协同性差异和城市功能综合得分差异,对协同水平进行分类。结果表明: 2016年,中国35个城市生态与经济社会平均协同性指数为28.79,协同性最强城市的协同性指数为3.83,最弱的城市为63.04,表明中国城市协同性不高且城市间差异较大。协同性指数、城市经济功能、社会功能与城市人口规模、经济规模呈显著正相关。不同人口规模、经济规模、不同行政职能城市之间协同性指数差异具有显著性。中国城市化总体仍处于功能失衡的发展阶段,城市发展有利于各城市功能性提高但并未有效提升协同性,生态功能的高低显著影响城市协同性,城市生态功能不高是当前中国城市协同性高低的主要制约因素。     

辽宁中部城市群城市非点源污染负荷评估

过去几十年我国经历了快速城市化过程,这使得不透水面大幅度增加,导致地表径流和洪峰流量增加,进入水体的污染物增多。城市非点源污染已成为河流水体恶化、生态系统退化的重要原因。在快速城市化过程中,城市群已成为城市化发展的新阶段。位于同一流域的各城市所产生的城市非点源污染导致城市群流域水环境问题越来越突出,成为制约城市群流域可持续发展的关键因素之一。现有的关于城市非点源的研究多集中于城市内部小尺度,对城市群大尺度的研究亟需发展。以位于浑河太子河流域的辽宁中部城市群为例,在沈阳市不同功能区和不同下垫面进行降雨径流采样,基于事件平均浓度（Event Mean Concentration, EMC）法和SWMM（Storm Water Management Model）模型相结合的方式,定量评估城市群流域城市非点源污染负荷。研究结果表明：路面径流中城市非点源污染物浓度、负荷量及其单位面积负荷要高于屋面径流和透水面径流。辽宁中部城市群TP、TN、COD、TSS的年均城市非点源污染负荷分别为265.52、852.89、2249.71、192496.74 t/a,重金属Cd、Ni、Pb、Cr、Cu、Zn的年均城市非点源污染负荷分别为347.99、9932.62、25861.29、28360.41、36068.30、138840.42 kg/a。沈阳市城市非点源污染负荷最高,但其单位面积负荷最低。本研究基于更为精细的城市下垫面划分,综合考虑城市功能区划、下垫面类型和降雨强度,更为准确的评估了辽宁中部城市群流域的城市非点源污染负荷。该研究能够为高度城市化流域城市非点源污染防控和水环境综合治理提供科学依据。     

环境因素对中国城市青少年体表面积发育的影响

用Stevenson和Du Bois公式计算30个省市城市7~18岁男女青少年的体表面积均值,并对其进行因子分析求得发育分。采用发育分与自然因素和社会经济因素进行相关分析和多元逐步回归分析,研究环境因素对中国城市青少年体表面积发育的综合影响。结果显示,中国城市青少年体表面积发育存在地域差异,男女青少年体表面积发育分排在前5位的均位于环渤海地区;发育分与地球经度、地球纬度、年日照时数、气温年较差、人均GDP、人均可支配收入以及每千人中卫生技术人员数呈显著性正相关,与海拔、年降水量、年均相对湿度、恩格尔系数、人口出生率、人口增长率以及儿童负担率呈显著性负相关;影响中国城市青少年体表面积发育的关键因素为海拔、年均相对湿度、恩格尔系数和儿童负担率。青少年体表面积发育在环境因素方面是受自然环境因素与社会经济生活两者之间共同相互作用的结果。     

Is urban green space per capita a valuable target to achieve cities’ sustainability goals? Romania as a case study

Urban green infrastructure is considered to be a key element in improving quality of life and creating an appropriate framework for sustainable cities. The most used quantitative indicator to assess urban green infrastructure is urban green space (UGS) per capita. This papeŕs aim is to analyze whether UGS is a valuable target to achieve cities’ sustainability goals. We used Romania as a case study, which should meet the target of 26 m² of UGS per inhabitants in all cities. Aerial images were used to extract the surface of the UGS categories for a sample of 38 cities in Romania. We compared our data with three other databases (National Institute of Statistics, Environmental Protection Agencies and Urban Atlas) to check for differences. To understand the contribution of geographic and socio-economic factors to the dynamic of the UGS per capita in Romania’s cities, we used a multiple linear regression. To identify differences between cities in terms of their proportions of UGS, multiple correspondence analysis was performed. We found significant differences between the surface of UGS reported by the administrative offices and that resulting from the spatial analysis. The process of reporting UGS data currently has methodological and perspective shortcomings. Moreover, the density of the built-up space, the proximity to major transport infrastructure, the cities’ founding period and the geomorphology criteria are important predictors for the UGS. The target of 26 m² of green area per inhabitant in all Romanian cities is not feasible and it should consider the cities’ characteristics, if you want to achieve sustainability goals. Urban green planning should focus more on the development of urban green infrastructure models that are adapted to each type of urban area.     

纯林、混交林型园林绿地的生态效益

试验选择元大都城垣遗址公园西段4块不同结构类型的绿地为研究对象,即草坪、刺槐纯林、油松纯林、刺槐．油松混交林,每一块试验地的面积在1000m^2左右,进行了连续8d的测试,通过试验观测与调查资料的分析,得出4块不同结构类型的园林绿地在水平方向和垂直方向上温度、湿度、风速的分布规律及差异。结果表明,在水平方向上,在3种天气条件下,油松纯林的水平日平均温度最低、相对湿度最高;在晴朗天气一天中的高温时段,草坪的温度最高,相对湿度最低,刺槐一油松混交林的相对湿度最高,温度最低。在水平方向上,经SPSS方差分析,4种绿地间的温、湿度差异均达到显著水平（α=0．05）。在垂直方向上,4种绿地的温度随着高度的升高逐渐升高,而相对湿度则随着高度的升高而逐渐降低;相对于其他绿地,混交林的温度和相对湿度变化比较复杂。刺槐-油松混交林的降温增湿效果最好,草坪的降温增湿效果最差。混交林型绿地降低风速的效果好于2种纯林。根据4种绿地在夏季的降温增湿效应提出混交林是园林绿地中生态效益较好的植物配置模式并提出了营造城市园林绿地植物景观的建议。     

Surveying the Environmental Footprint of Urban Food Consumption

Assessments of urban metabolism (UM) are well situated to identify the scale, components, and direction of urban and energy flows in cities and have been instrumental in benchmarking and monitoring the key levers of urban environmental pressure, such as transport, space conditioning, and electricity. Hitherto, urban food consumption has garnered scant attention both in UM accounting (typically lumped with “biomass”) and on the urban policy agenda, despite its relevance to local and global environmental pressures. With future growth expected in urban population and wealth, an accounting of the environmental footprint from urban food demand (“foodprint”) is necessary. This article reviews 43 UM assessments including 100 cities, and a total of 132 foodprints in terms of mass, carbon footprint, and ecological footprint and situates it relative to other significant environmental drivers (transport, energy, and so on) The foodprint was typically the third largest source of mass flows (average is 0.8 tonnes per capita per annum) and carbon footprint (average is 2.1 tonnes carbon dioxide equivalents per capita per annum) in the reviewed cities, whereas it was generally the largest driver of urban ecological footprints (average is 1.2 global hectares per capita per annum), with large deviations based on wealth, culture, and urban form. Meat and dairy are the primary drivers of both global warming and ecological footprint impacts, with little relationship between their consumption and city wealth. The foodprint is primarily linear in form, producing significant organic exhaust from the urban system that has a strong, positive correlation to wealth. Though much of the foodprint is embodied within imported foodstuffs, cities can still implement design and policy interventions, such as improved nutrient recycling and food waste avoidance, to redress the foodprint.     

Comparative analysis of passenger transport sustainability in European cities

Sustainable development in its three dimensions – economic, social and environmental – has become a major concern on an international scale. The problem is global, but must be solved locally. Most of the world’s population lives in cities that act as centres of economic growth and productivity, but which – if they develop in the wrong direction – can cause social inequalities, or irreversibly harm the environment. Urban transport causes a number of negative impacts that can affect sustainability targets. The objective of this study is to propose an analysis of sustainability of urban passenger transport systems based on available indicators in most cities. This will serve to benchmark the practices of different cities and manage their transport systems. This work involves the creation of composite indicators (CI) to measure the sustainability of urban passenger transport systems. The methodology is applied to 23 European cities. The indicators are based on a benchmarking approach, and the evaluation of each aspect in each case therefore depends on the performance of the whole sample. The CI enabled us to identify which characteristics have the greatest influence on the sustainability of a city’s transport system, and to establish transport policies that could potentially improve its shortcomings. Finally, the cities are clustered according to the values obtained from the CIs, and thus according to the weaknesses and strengths of their transport systems.