Spatiotemporal landscape pattern changes and their effects on land surface temperature in greenbelt with semi-arid climate:A case study of the Erbil City,Iraq

Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.

Species and Distribution Characteristics of Alien Invasive Plants in Garden Greenbelt of Shijiazhuang City

[Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,etc.in Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of public gardens were recorded through point-line-surface investigation,and typical plants were sampled.[Results]There were 56 species of alien invasive plants in garden greenbelts of Shijiazhuang City,belonging to 44 genera and 20 families.In terms of life form,herbaceous plants were absolutely dominant,accounting for 92.8%of the total.The most alien invasive plants were native to America,accounting for 66.1%of the total.In terms of introduction path,the plants introduced artificially and unintentionally accounted for almost half.The species and quantity of alien invasive plants were related to the size of greenbelt area,the length of the build time of the surveyed plot,the composition structure of greenbelt and the level of green management and protection.There was larger distribution of alien invasive plants in the sample plots with large greenbelt area,long build time,herbaceous-dominated greenbelt and low level of green management and protection.Among the 56 alien invasive plants,3 plants were toxic.From the perspective of invasiveness,the alien invasive plants in the garden greenbelt of Shijiazhuang City could be divided into 5 levels:invasive alien species of malignant consequences,invasive alien species of severe consequences,invasive alien species of partial consequences,invasive alien species of average consequences,and invasive alien species to be observed.[Conclusions]This study will provide a reference for the prevention and control of alien plant invasion,and lay a foundation for the prevention and control of existing invasive plants.

北京市绿隔地区生态环境质量变化与驱动因素分析——以“基于自然的解决方案”为视角

引入“基于自然的解决方案”(NBS)视角,借助空间计量模型,分析绿隔地区的生态环境质量变化及其驱动因素,得到以下结果:1)从生态环境质量变化看,2005—2020年,绿隔地区整体上呈现先下降后回升的趋势,空间上圈层格局明显;2)两道绿隔地区的生态环境质量变化趋势不同,第一道绿隔地区相对更低,且一直延续下降趋势,第二道绿隔地区2015年后止降回升;3)从驱动因素看,NBS措施对绿隔地区生态环境质量改善具有驱动作用,其中绿色基础设施在两道绿隔地区都表现出显著的驱动作用,而生态基础设施仅在第二道绿隔地区表现出显著的驱动作用。北京市进入减量发展新阶段以来,绿隔地区的生态环境质量明显改善。未来可以更有针对性地应用NBS措施,进一步提升城市生态环境质量,完善城市绿色空间体系建设。

Investigation on the Characteristics of the Senior Citizens' Activities in the Parks and Greenbelts——A Case Study of Nanjing City

From the perspective of senior citizens,questionnaire survey and field investigation were carried on and analyzed in three parks in Nanjing City.The results showed that outdoor activities are the principal ways for the senior citizens to spend their time,the parks near home is their prior choice,and the radiation range of the park and greenbelt mostly is no more than 2 km;most of the senior citizens come to parks on foot and the parks are always within 30 minutes walking distance;the senior citizens always have fixed partners and groups for their exercise-dominant activities.

Effects of Greenbelts in Different Variety under Solar Thermal Radiation on Temperature Reduction

[Objective] The aim was to study on effects of greenbelts in different varieties on temperature drop under solar thermal radiation. [Method] In residential regions, effects of temperature reduction by five varieties of greenbelts （megaphanerophyte, dungarunga, shrub, herbaceous plant and bare land） and changing rules with days under the same solar thermal radiation were researched. [Result] Greenbelts＇ temperature changed with intensity of solar thermal radiation, among which greenbelt of megaphanerophyte absorbed, transfered and reflected thermal radiation through crown canopy. Temperature of underlying surface was reduced accordingly, where correlation between underlying surface＇s temperature and solar thermal radiation （R） was 0.156 and the temperature declined by 1.9 ℃. In contrast, correlation of temperature of underlying surface （of lawn） with solar thermal radiation （R） was as high as 0.820, but the temperature only declined by 0.6℃. [Conclusion] The established linear relationship between crown＇s temperature and air temperature actually provides references for temperature measurement of greenbelts at scale.

Road Greenbelt Design of Zhangye City

Road greenbelt design is one of the important parts in urban road system.Zhangye City's road greenbelt design,relying on the general planning concept,namely,'water leads to green space,green space blends the city',emphasizes the harmonious relation between the greenbelt and ecological environment.The concept is adopted to guide the green design of the major roads,subsidiary roads,and trunk roads.It will offer some references for the similar engineering design.

张家口市宿根花卉资源及绿化应用潜力分析

[目的]引用宿根花卉可有效解决张家口地区园林绿地一年生观赏草本花卉花期短、品种单调、更换次数多和维护成本高的问题。[方法]本研究基于实地踏勘,调查了张家口地区具有代表性的绿地中宿根花卉应用情况,并分析了宿根花卉生长发育的相关性状指标。[结果]相比于一年生草本花卉,张家口市宿根花卉种类较多,各类绿地共有宿根花卉17科41属45种,其中菊科9种、唇形科5种、鸢尾科3种,分别比同科一年生草本花卉多2倍、1.5倍、1倍。相比于一年生草本花卉,宿根花卉花色更为丰富,其花色共计11种,比一年生草本花卉多1.2倍。张家口市宿根花卉花色为黄色、蓝色和白色的花卉占据比例较高,分别为24.4%、17.1%和14.6%。不同种类宿根花卉观赏期在210~240 d之间,比一年生草本花卉长130%~160%。宿根花卉的萌动期集中在3月下旬到4月中旬,同一植物种植不同地点萌动期不同,公园游园植物萌动期比主干道提前3~5 d。不同种类宿根花卉覆盖度、越冬成活率和萎蔫率分别在90%~95%、81.6%~100%和0%~36.7%。宿根花卉第1年种植人工费及后期养护成本比一年生草本花卉低12元,第2年及以后投入成本仅为一年生草本花卉的6%左右。[结论]张家口地区宿根花卉种类较多,且具有更高的观赏价值和更低的后期管理成本,应用潜力比一年生草本花卉更大。

不同类型配生土与固体废弃物大田配施对绿地土壤理化性质和白玉兰生长的影响

为研究白玉兰配生土与固体废弃物配施对绿地土壤理化性质和白玉兰生长的影响,利用4种白玉兰配生土(降盐型、沃土型、消污型和疏松型)与3种固体废弃物(建筑废弃物、农林废弃物和餐厨垃圾有氧发酵初产物)进行大田配施,于白玉兰种植后180d、360d和720d分别测定表层土壤(0—30cm)pH、水溶性盐分含量、有机质含量、容重以及白玉兰相对生长率和叶绿素含量。结果表明:4种配生土和3种固体废弃物大田配施后,与原土处理(CK)相比,土壤pH和容重分别降低了8.53%—13.36%和22.62%—48.61%,水溶性盐分和有机质含量分别提高了182.9%—745.9%和38.45%—279.3%;种植后720d,白玉兰株高相对生长率提高了25.9%—102.9%,叶绿素含量提高了46.95%—67.38%。综合考虑土壤改良效果和固体废弃物消纳能力,处理降盐型Y2、沃土型F3、消污型M2和疏松型S2对土壤质量的改良及白玉兰植株生长作用较好,同时有助于固体废弃物的消纳和资源化利用。

临沂市高架桥雨水收集利用探讨

为了解决高架桥下绿化带的灌溉问题,结合临沂市双岭路高架路海绵城市改造提升建设工程,研究开发了一种新型高架桥雨水收集利用系统。该系统利用雨水收集箱和塑料模块蓄水池收集高架桥面的雨水,灌溉桥下绿化带。应用结果表明:该系统降低了市政管网建设和城市道路运营维护成本,具有操作简单、成本低、维护方便等优势,适合临沂市高架桥工程现状,对临沂市高架桥道路雨水收集系统的建设发展有着促进作用,同时对推动市区海绵城市道路建设的可持续发展,有较大的创新性与推广价值。本文成果可为国内其他城市道路海绵城市建设、雨水收集利用方面的研究与实践提供一定的借鉴。

Evaluation and classification of residential greenbelt quality based on factor analysis & clustering analysis:An example of Xinxiang City,China

Five factors expressing greenbelt quality and one factor expressing quantity were adopted for evaluation of the residential greenbelt, and the AHP （Analytical Hierarchy Process） method was used to determine the value of factors. Thirty residential areas were selected as the samples. Two principal components were extracted and their expression was constructed by method of factor anlysis, therefore, quality evaluation of residential greenbelt was obtained. The accuracy of the function and implement quality classification toward the residential greenbelts in Xinxiang City were validated by clustering analysis method. The results showed that the greenbelt quality of fourteen residential areas was higher than the average level, of which eleven were newly-built residential areas. The 30 residential areas were classified into three types according to their greenbelt features and their formation by clustering analysis method. Finally rational proposal basing on aforesaid evaluating results was proposed for construction and renewal of residential greenbelt, upon which directive basis was provided for construction and renewal of residential greenbelt.

Construction of Greenbelt and Sustainable Development in Harbin City

Through analyzing the current urban greenbelt construction and relative issues during the development in northeastern parts in Harbin of China, some feasible solutions were proposed. In order to improve the urban ecological environment and upgrading the constructive level of the urban greenbelt along with the sustainable development in the future, the paper provided some solutions in details

石家庄市园林绿地外来入侵植物种类及分布特征

通过对公园、道路、小区(园区)等30个调查样区园林绿地的调查,发现石家庄市园林绿地中共有20科44属56种外来入侵植物。在生活型上,草本植物占绝对优势,为92.9%;原产地为美洲的最多,占66.1%;在引入途径上,人工引种和无意引入的植物几乎各占一半;外来入侵植物分布的种类和数量与绿地面积大小、样区建成时间的长短、绿地组成结构以及绿化管护水平相关,其中绿地面积大、建成时间长、绿地以草本植物为主、绿化管护水平较低的样区分布较多;在56种外来入侵植物中有3种具有毒性,从入侵性上看,外来入侵植物共分为恶性入侵类、严重入侵类、局部入侵类、一般入侵类以及有待观察类5个等级。

城市绿地土壤研究文献的CiteSpace可视化分析

【目的】城市绿地土壤的质量直接关系到城市生态效益及各项功能的发挥。分析中外城市绿地土壤研究文献,梳理与总结中国城市绿地土壤研究重点及未来发展方向。【方法】检索中国知网(ChinaNationalKnowledge Infrastructure)和科学网(Web of Science)核心数据库中2012—2021年关于城市绿地土壤的研究文献,利用CiteSpace从发文量、国家及机构分布、代表人物及热点内容、研究重点内容、研究发展趋势及前沿等方面,阐明该研究领域的重点内容及动态发展。【结果】近10年城市绿地土壤研究领域共发表中英文文献1 107篇,其中中国发文总量最多,且主要集中在中国科学院。国内研究内容主要为土壤质量,研究热点从土壤肥力质量到土壤污染,再到土壤改良修复。国外研究内容主要是城市绿地土壤的生态系统服务功能,研究热点从解决城市生态环境问题到提出绿地维护管理策略,再到提升城市生态环境效益。研究前沿集中在重金属污染和城市绿地生态系统。【结论】城市绿地土壤中英文文献的研究重点不同,中文文献更关注城市绿地土壤质量,这与国家政策、城市发展、生态环境保护等有关。而英文更关注城市绿地生态系统,这可能与气候变化、绿色基础设施建设、生态环境效益等有关。图3表5参58。

晋南地区主要城市道路绿地的表层土壤性质

为了探究晋南地区各城市道路绿地土壤的性质及肥力现状,判断其是否适合绿化植物生长,在晋南地区4个地级市(临汾、长治、运城和晋城)选取道路绿地样带,测定其表层土壤(0~15 cm)的理化性质,并基于修正的内梅罗指数法进行土壤综合肥力评价.结果表明:(1)晋南地区城市道路绿地土壤质地较为黏重,平均pH值为8.39,全氮含量为0.39 g/kg,土壤碱化,氮素匮乏.(2)土壤孔隙状况良好,无压实退化,有机碳和磷素较为充足.(3)土壤综合肥力指数由大到小为晋城≈长治>运城>临汾,4个城市平均值为1.23,处于中等水平.(4)随着土层深度的增加,黏粒含量和土壤容重增加,碳、氮含量减小.(5)利用偏最小二乘(PLS)回归预测土壤肥力综合指数,所得模型对综合肥力指数的解释力为89%,预测结果可靠.

基于绿地微气候的长沙太平街历史文化街区热环境数值模拟

以长沙太平街历史文化街区为研究对象,首先对街道空间的现状微气候环境做分析,然后基于ENVImet软件进行数值模拟,并将研究区3种典型的街道空间的绿化优化方案的微气候数值模拟结果与基准方案的差值进行比较,进而阐释绿化优化方案的热环境调控程度。结果表明:1)随着太阳辐射逐时的变化,研究区域的热环境状况发生较大变化,在水平空间分布上呈“高温低湿”“低温高湿”特征。2)热环境质量与下垫面状况、风环境和建筑布局等因素的有关。3) 3种街道空间提高街区绿地面积均可大幅降低街区平均辐射温度,乔灌+立体(水体)复合型绿地类型的热环境优化调控作用在白天均要优于乔灌、乔草方案。在绿地率一定的情况下,商业空间绿地布局中由于绿化均匀分散布局产生的树荫面积覆盖街道空间的范围最大,热环境优化调控程度的排序为分散>平行>集中,而居住空间和广场空间受建筑布局影响,绿地布局在降温增湿同时应兼具良好通风效应,因此热环境优化调控程度最大为集中布局。

基于生态效应的城市绿色空间体系构建--以西安国际港务区绿带公园为例

城市绿色空间是城市生态的载体,城市绿色空间系统的建设尤为重要。城市绿色空间系统不仅为城市居民提供了休闲娱乐的场所,还有助于改善空气质量、调节城市微气候、保护生物多样性等。然而,随着城市化进程的加速,城市绿色空间系统的建设面临诸多挑战,其中之一便是生态效应与城市绿色空间体系的构建。正因如此,将城市与绿色自然空间融合已成为现代城市空间建设的普遍选择。通过西安国际港务区新建绿带公园为例,探讨分析在城市绿色空间建设过程中所采用的区域生态构建、功能补充和多尺度协同实践模式,以期为城市绿色空间体系的构建提供理论支持和实践参考。

滁州学院南校区不同类型绿地微气候效应分析

为了探究微气候效应与人体热舒适度,提升校园生活环境质量,以滁州学院南校区不同绿地为研究对象,采用定点测量法对微气候要素进行实测,并在实测点2 m外发放调查问卷。结果显示,空气温度在3.6℃~14.4℃、相对湿度为39.6%~69.4%、风速为0.4~1.5 m·s^(-1)、太阳辐射为6.4~185 w/m^(2)的条件下,3/4的学生对室外热环境有不同的感觉,热舒适接受为72.79%,不可接受为27.21%。人体热舒适度(PET)范围为9.1℃~22℃,PET与温度之间有极强正相关性,系数区间为0.667~0.984;PET与相对湿度有着极强负相关性,系数为0.639~0.955;PET与风速有负相关性,系数为-0.457~-0.524;太阳辐射与PET有正相关性,系数为0.536~0.694。此研究可为校园生活质量改善提供依据,以加强冬季校园热环境建设。

惠州城市公园绿地自生植物调查分析

自生植物在城市环境中不仅能明显减轻养护管理负担,而且在构建可持续低投入维护的园林植物景观中具有重要地位。以惠州市城市公园为研究对象,采用样方法,对城市公园绿地自生植物进行调查,并深入分析其物种组成特征和群落特点。结果表明:本次研究共调查自生植物121种,隶属于44科105属,以豆科(Fabaceae)、菊科(Compositae)、禾本科(Gramineae)、大戟科(Euphorbiaceae)、莎草科(Cyperaceae)等5个科为优势科;生活型组成十分丰富,其中一年生草本植物最多,共计有41种。植物来源以乡土植物为主,有59种,占48.76%;国内外来植物有51种,占42.15%;国外外来植物有11种,其中入侵植物有7种。在群落多样性方面,不同生境中自生植物群落多样性存在显著差异。

基于环境承载力的下沉式绿地污染物迁移数学解析模型

为高效评价下沉式绿地污染物净化效能以及对周边环境生态的影响,系统建立了下沉式绿地雨水径流污染物一维迁移数学解析模型,并给出污染物相对浓度变化以及累计通量去除率的数学解析表达式,并用试验数据验证了模型的合理性和可靠性。基于模型计算结果,分别得到了设定条件下Pb^(2+)污染物击穿曲线以及其累计通量去除率曲线。并发现蓄水高度从5 cm增长至15 cm,会使Pb^(2+)污染物累计通量去除率减少35%,污染物击穿时间从110 h缩短至36 h。此外,还揭示了污染物击穿时间和累计通量去除率随下沉式绿地土层渗透系数减小而增大的规律。基于解析模型,给出了生态设计约束条件,可有效避免初期雨水径流对植被及地下水土造成的污染。该数学解析模型的提出为海绵城市设计、城市水环境治理、地下水土污染控制等工程应用提供理论依据和技术指导。

海绵城市建设低影响开发设施的改良

针对海绵城市建设中经常存在海绵设施破坏景观效果,雨水调蓄设施(下沉式绿地等)出现“大水坑”,导致蚊蝇滋生等现象,经分析研究,对雨水花园、高位花坛、植草沟和下沉式绿地、渗透渠等海绵设施进行了技术上的创新改良,使之能融合景观,彰显海绵城市低影响开发的理念。