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1.
江苏北部城镇绿化策略研究   总被引:4,自引:0,他引:4  
在对江苏北部气候,植物区系,森林植被研究的基础上,从生态学角度提出该地区城镇绿化策略,包括:立足于落叶阔叶树种,积极引种耐寒发阔叶树种,根据生境特点合理布局树种。  相似文献   

2.
调查了神东矿区23个单位附属绿地的绿化结构,测定并评价了绿地的各种功能效益和蒸腾耗水量,最后选择绿地持续稳定、功能效益、蒸腾耗水量、整体美景度4个方面10个指标,用主成分分析法综合评价了不同绿地配置模式的优劣顺序,筛选出较好的配置模式。评价分析表明:上湾小学总体表现最好,神东煤矿职工生活小区总体表现普遍较差;绿量是决定城市绿地功能效益的关键因素,城市绿化不仅要增加绿化覆盖率,还要注重提高单位面积绿地绿量;乔木树种不仅绿量和发挥的功能效益最大,蒸腾耗水量也很大,因此,干旱半干旱地区城市单位附属绿地在提高节水乔木树种(如新疆杨Populus alba var.pyramidalis)比例的同时,还应注重配置花灌木树种(如玫瑰Rosa rugosa、紫丁香Syringa oblata),并适当地用自然杂草代替人工草坪覆盖地表,以适应干旱地区水分短缺的需求。  相似文献   

3.
生态系统服务是生态系统功能中有利于人类福祉的部分,生态系统功能向服务的转化研究成为未来生态系统服务评估的重要发展方向.以大气环境污染较为严重的北京市和陕西省关中地区的城市森林生态系统为例,利用气溶胶再形成法,研究不同树种和污染区城市森林生态系统滞纳空气颗粒物能力,探讨其向服务的转化率问题.结果表明,城市森林生态系统中不同树种滞纳空气颗粒物功能向服务的转化率存在差异,雪松最高,达95%,而白皮松最低,仅为47%,树种滞纳颗粒物能力与转化率没有必然联系,电镜扫描结果显示与叶表微观结构特征如气孔大小或多少、绒毛长短、蜡质层有无等有关.空气污染强度不同的多个城市中,转化率为宝鸡西安咸阳韩城杨凌渭南铜川,空气污染严重的城市转化率较高,空气质量优越且颗粒物含量少的城市,转化率相对较低.因此,叶片表面结构和树种所处地区的空气污染程度共同决定了城市森林生态系统滞纳空气颗粒物功能向服务的转化率;空气质量较差地区应增加绿地面积、提高植被覆盖率,有针对性地选择转化率较高的树种.  相似文献   

4.
通过野外实测和数据收集的方法,运用层次分析法建立了佛山市绿地系统评价指标权重体系。结果表明:佛山市城市绿地系统综合效益处于一般水平,得分为0.383。佛山市绿地系统存在绿地斑块分布不均,绿化植物品种单一,忽视本地种的开发等问题。全绿化率最高的三水区达35.20%,最低绿化率禅城区则只有14.31%;乡土树种仅占全部绿化树种的30%;群落结构较简单,道路附属绿地的群落层片结构多为2层,地被植物品种单一。  相似文献   

5.
藤本植物在城市垂直绿化中的选择与配置   总被引:13,自引:0,他引:13  
藤本植物是指不能自由直立生长,需要借助于其他植物或支撑物的支持才能向上生长的植物的总称。藤本植物具有生长迅速、占地面积少、绿化面积大、种植管理容易等优点,它在现代城市绿化,特别是城市垂直绿化中运用十分广泛。城市垂直绿化的形式可分为:墙面绿化、立柱绿化、篱垣绿化、护坡绿化、棚架绿化、屋顶绿化。总结了藤本植物的特点和它的运用原则,重点介绍了它在不同垂直绿化形式中的具体的选择与配置技术。  相似文献   

6.
北京市25种公路绿化植物及配置模式的绿量   总被引:1,自引:0,他引:1  
计量研究公路绿地的生态服务功能有助于科学评估公路绿化的无形价值。以北京市顺义区顺平路(S305)的绿化植物群落为研究对象,运用WinScanopy For Canopy Analysis冠层分析仪采集数据,研究了公路绿化常见植物及配置模式的绿量率,并建立了25种公路绿化常见植物的绿量率模型,以期为公路绿化树种选择和群落配置提供基础分析与参考。结果表明:阔叶乔木的绿量率在3.02~4.80之间,针叶乔木的绿量率集中在4~6之间,灌木植物的绿量率较小,种植紧凑的绿篱绿量率达到3.94;不同配置模式的群落绿量率大小顺序依次为:针阔混交林>阔叶林>针叶林>灌木群落。其研究结果为公路绿化建设和绿地生态效益的计量提供了科学依据。  相似文献   

7.
太原城区绿化植物受氯气伤害的特征及其抗性的研究   总被引:1,自引:0,他引:1  
本文采用开顶式熏气试验技术,对太原城区栽植的某些树种、花卉和草坪植物的叶片受氯气污染的伤害特征及其熏气后的“远后效应”进行了研究,并根据这些植物的抗氯气能力进行了分级、提出适于氯气污染区的绿化植物和监测植物。  相似文献   

8.
为向城市草坪的冬季管理提供科学依据,向城市生态系统的碳收支评估提供基础数据,研究了成都市最具代表性的两种城市草坪——沟叶结缕草草坪和麦冬草坪冬季土壤呼吸速率的动态变化及其影响因子.结果表明:沟叶结缕草草坪和麦冬草坪整个冬季土壤呼吸速率分别在1.20-3.17μmol m-2 s-1和0.85-2.43μmol m-2 s-1范围波动,且土壤呼吸动态均呈"V"型曲线,先降低后升高;冬季两种草坪土壤呼吸速率与土壤理化性质和植物生长习性有关;休眠期土壤呼吸速率主要受土壤温度调控,与土壤水分相关性不大;而双因素回归分析表明,温度和水分共同可解释土壤呼吸的75%-84%;沟叶结缕草草坪土壤呼吸温度敏感性(Q10)比麦冬草坪高41.85%.可见,两种草坪冬季休眠期土壤呼吸速率均较高,冬季土壤碳排放与草种选择有关.  相似文献   

9.
兰州市空气污染防治绿化对策   总被引:6,自引:0,他引:6  
依据植被对大气污染物净化能力和绿化对大气污染扩散条件的改善等研究成果,并结合兰州市自然地理环境和土壤水分条件以及本地小气候特点和实际地表植被状况,从植物对空气污染物的生物净化作用角度出发,探讨了兰州市大气污染治理的最佳绿化方案,以期对兰州市大气污染的综合治理提供理论依据。  相似文献   

10.
城市森林对大气中重金属的富集特征   总被引:1,自引:0,他引:1  
为了探究城市森林不同树种对大气中重金属的富集能力和分析大气环境质量状况,本文以昆明市东三环边坡的城市森林为试验区,玉溪市磨盘山国家森林公园为对照区,选取两地区分布最广泛的蓝桉、云南松、华山松、圆柏为实验对象,通过测定植物叶片中的重金属含量,对其季节变化规律及重金属元素含量间的相关性进行了分析,结果表明:(1)植物叶片中重金属Zn、Cu、Pb、Cd含量(由春到冬)呈先下降后持续上升的变化趋势;Zn含量春季处于最高值(120.63 mg·kg-1);其余3种重金属元素含量冬季达到最高值.(2)叶片中Cu和Pb含量相关性极显著、金属元素的总含量和Zn、Cd的含量也极显著相关,其相关系数均达到0.85以上;Zn和Pb含量的相关性不显著.大气中重金属Pb污染严重的地区可选择华山松作为城市主要绿化树种、Zn污染严重的地区可选择蓝桉、Cu污染严重的地区可选择圆柏、Cd污染严重的地区4种植物均可选择;试验区的空气污染等级达到了Ⅱ级污染,属于轻度污染区,其中春季大气的综合污染指数最高.  相似文献   

11.
城市绿地滞尘作用机理和规律的研究进展   总被引:7,自引:0,他引:7  
城市绿地的滞尘作用是城市绿地重要的生态功能之一。综述了城市绿地的滞尘机理、变化规律。城市绿地的滞尘机理主要分为3种方式:滞留、附着和粘附;城市绿地滞尘能力与滞尘时间、城市环境、植物种、植物群落结构等因素存在密切的联系。不同植物滞尘能力的差异很大,总体规律表现为乔木植物〉灌木植物〉草本植物;但就单位叶面积来说,滞尘能力均以草本植物〉灌木植物〉乔木植物〉藤本植物;主要原因是垂直高度不同,灌草能有效截留地面的扬尘(城市中灰尘的主要来源)。研究表明,同种类植物种在封闭式环境条件下叶片滞尘量明显低于开敞式环境条件下的滞尘量,因此,在城市不同环境中的植物滞尘能力表现为工业区〉商业交通区〉居住区〉清洁区。随着季节和滞尘时间的变化,每种植物都存在一个滞尘限度,如果无雨水或人为干扰,最终达到一个动态平衡。从城市绿地群落的垂直结构看,乔—灌—草型的绿地具有相对较好的滞尘作用,是目前较为理想的绿地类型;另外,在城市绿地面积明显不足的情况下,以藤本植物为主的垂直绿化将成为城市绿化发展的新方向。同时,在城市绿地滞尘机理、规律以及植物滞尘能力评价等方面仍需要进一步深入研究。  相似文献   

12.
When reproduction competes with the amount of resources available for survival during an unpredictable nonbreeding season, individuals should adopt a risk-sensitive regulation of their reproductive allocation. We tested this hypothesis on female reindeer (Rangifer tarandus), which face a trade-off between reproduction and acquisition of body reserves during spring and summer, with autumn body mass functioning as insurance against stochastic winter climatic severity. The study was conducted in a population consisting of two herds: one that received supplementary winter feeding for four years while the other utilized natural pastures. The females receiving additional forage allocated more to their calves. Experimental translocation of females between the herds was conducted to simulate two contrasting rapid alterations of winter conditions. When females receiving supplementary feeding were moved to natural pastures, they promptly reduced their reproductive allocation the following summer. However, when winter conditions were improved, females were reluctant to increase their reproductive allocation. This asymmetric response to improved vs. reduced winter conditions is consistent with a risk-averse adjustment in reproductive allocation. The ability of individuals to track their environment and the concordant risk-sensitive adjustment of reproductive allocation may render subarctic reindeer more resilient to climate change than previously supposed.  相似文献   

13.

Aims and Scope

Over recent decades, the climate has changed. Up to now this statement has been made predominantly for the global and/or continental area. What, however, is the situation regarding the climatic trend at the regional scale? Is it already possible to show effects of a climate change in small-scale landscape structures? These questions were addressed looking at the example of the situation in the federal state of Rhineland-Palatinate (Germany).

Methods

Phenological data of plants of the last 50 years from a total of 386 stations of the German Weather Service (DWD) were evaluated. The timing of the different plant phases, beginning of the foliation and plant senescence in autumn, flowering and the first ripening of the fruits had to be registered for different agricultural crops, wild plants, ornamental woods as well as fruit trees. The analysed data material was used to develop the threefold phenological clock (DPU).

Results

Summarising the findings of the DPU for the 15 evaluated nature districts of Rhineland-Palatinate according to individual seasons, which were defined in generic terms as spring, summer, autumn and winter, a tendency of a prematuring of the spring, a prolongation of the autumn as well as a shortening of the winter is evident. From a regional point of view, on the other hand, in individual nature districts such as the ‘Westerwald’ and the ‘Bergisch-Sauerländische Gebirge’, winter seasons are getting longer. Thus the effects of a climate change can differ considerably from region to region.

Outlook

The regionally quite different changes of the climatic situation in Rhineland-Palatinate will not remain without an effect on the ecosystems of this federal state. The currently existing biocoenosis will therefore change. The consequences for forestry, agriculture and nature conservation are of special interest in this context.  相似文献   

14.
Trees in the subalpine environment, a particularly vulnerable area being the first to reflect climate changes, are most likely to show strong effects of climate variability. The aim of this study was to identify growth responses of subalpine fir (Abies fargesii) to climate variability, and investigate range shifts along an altitudinal gradient in the subalpine region of the Qinling Mountains, China. Standard correlation functional analysis showed different growth responses of fir trees to climatic variables between north and south aspects. In the north aspect, radial growth was significantly positively correlated with temperatures in early spring (February–April) and summer (July) of the current year, while radial growth was significantly positively correlated with temperatures in November and December of the previous year and early spring (February–April) of the current year in the south aspect. Analysis of age structure distribution displayed a decrease in number of mature fir trees and an increase in number of saplings along the altitudinal gradient on both aspects. Fir saplings/seedlings only occur in the treeline environment, and this fir population was significantly younger than that at lower elevations. Thus, fir trees show different radial growth patterns in response to climatic variability between north and south aspects, and age-class distributions along the altitudinal gradient imply an upward shift in range in the subalpine region during the past century in the Qinling Mountains of China.  相似文献   

15.
《Ecological modelling》2005,182(2):159-181
Plant species’ climatic range limiters provide clues to reconstruct past climates, restore ecosystems, and manage agricultural systems. However, precise climatic limiters are unknown for many important species, and determining them typically involves long-term autecological studies. A new method presented here automatically and quantitatively infers limiters for a plant species using its documented, digitized distribution. The method uses available and accessible elevation and climate datasets from the US Geological Survey (USGS) and NOAA, along with common off-the-shelf (COTS) geographic information software technology (GIS) to determine which variables in the plant distribution climate space are actually limiting the range by restricting its movement into surrounding territory. The method utilizes precision climate interpolation allowing for independent variables in addition to latitude and longitude, via a software package developed at Australian National University (ANUSPLIN). For this first run, elevation and slope were included as independent variables for interpolating precipitation and temperature surfaces. The model defined limits for five Sonoran Desert plant species: Carnegiea gigantea, Cercidium microphyllum, Encelia farinosa, Ferocactus acanthodes, and Larrea tridentata. Results were tested against environmental factors outlined in autecological studies. Important model-derived climatic constraints to the distribution of C. gigantea include insufficient monsoon precipitation, low winter and monsoon temperatures, and excessive monsoon and fall precipitation. The distribution of C. microphyllum is constrained by cold winter and fall temperatures, excessive spring and summer precipitation and insufficient fall precipitation. E. farinosa is restricted by frigid winter temperatures and too much summer rainfall. Key factors limiting F. acanthodes are cold winter temperatures and inadequate fall and monsoon precipitation. An inordinate amount of precipitation during the summer, monsoon, and fall constrict the range of L. tridentata, along with an abnormally cool summer or monsoon. Results indicate that the method adequately resolves plant range limiters consistent with the autecological record. Future changes to the model are offered to improve results.  相似文献   

16.
Butterfly populations are naturally patchy and undergo extinctions and recolonizations. Analyses based on more than 2 decades of data on California's Central Valley butterfly fauna show a net loss in species richness through time. We analyzed 22 years of phenological and faunistic data for butterflies to investigate patterns of species richness over time. We then used 18–22 years of data on changes in regional land use and 37 years of seasonal climate data to develop an explanatory model. The model related the effects of changes in land‐use patterns, from working landscapes (farm and ranchland) to urban and suburban landscapes, and of a changing climate on butterfly species richness. Additionally, we investigated local trends in land use and climate. A decline in the area of farmland and ranchland, an increase in minimum temperatures during the summer and maximum temperatures in the fall negatively affected net species richness, whereas increased minimum temperatures in the spring and greater precipitation in the previous summer positively affected species richness. According to the model, there was a threshold between 30% and 40% working‐landscape area below which further loss of working‐landscape area had a proportionally greater effect on butterfly richness. Some of the isolated effects of a warming climate acted in opposition to affect butterfly richness. Three of the 4 climate variables that most affected richness showed systematic trends (spring and summer mean minimum and fall mean maximum temperatures). Higher spring minimum temperatures were associated with greater species richness, whereas higher summer temperatures in the previous year and lower rainfall were linked to lower richness. Patterns of land use contributed to declines in species richness (although the pattern was not linear), but the net effect of a changing climate on butterfly richness was more difficult to discern. Contribución de la Expansión Urbana y un Clima Cambiante a la Declinación de la Fauna de Mariposas  相似文献   

17.
近年来长江流域气溶胶光学厚度时空变化特征分析   总被引:6,自引:0,他引:6  
利用2000年3月至2011年2月MODIS Level3遥感反演大气气溶胶光学厚度(AOD)产品数据,结合中国地形的3大阶梯分布,分析近年来长江流域气溶胶光学厚度的时空变化特征。结果表明,近12年来,长江流域的年平均AOD值在0.38,~,0.44之间变化,其中“第一阶梯”年平均AOD呈极显著下降趋势(P〈0.01),“第二阶梯”和“第三阶梯”则呈上升趋势,但趋势不显著(P〉0.05);4季平均AOD除春季呈下降趋势,其他3季均为上升趋势,其中冬季上升速率最快,线性倾向率为0.004·a-1(P〈0.05),春季AOD与其他季节的差距在逐步减小;长江流域3大阶梯AOD具有鲜明的季节变化特征,基本上是春夏季较大,秋冬季较小,具体表现为春季最大,从夏季到冬季逐渐减小,冬季到来年春季跳跃性增高,但由于地理位置、地形、气候、人类活动等因素的影响,不同区域又有所差异;AOD年平均值和四季平均值均表现为“第三阶梯”〉“第二阶梯”〉“第一阶梯”。长江流域年平均AOD变化空间差异显著,其中显著减少区域占整个流域面积的17.54%,主要分布在“第一阶梯”;显著增加的区域仅占流域总面积的5.23%,主要分布在“第二阶梯”和“第三阶梯”。另外,由于海拔、地形及山脉阻挡等诸多因素影响,导致在地形阶梯间高程突变线左右两边的狭窄区域,AOD分布存在低处明显大于高处的现象。这些结果有助于长江流域的区域气候变化和环境研究。  相似文献   

18.
流沙湾海水中石油烃的时空分布特征研究   总被引:1,自引:0,他引:1  
于2008年2月(冬季)、5月(春季)、8月(夏季)和11月(秋季)对流沙湾进行了4次采样考察,研究分析了流沙湾表层海水中石油烃质量浓度的平面分布和季节变化特征。结果表明,在2008年度,流沙湾表层海水石油烃的质量浓度为0~1.930 mg.L-1,平均值为0.080 mg.L-1,季节差异比较明显,呈春、冬、夏、秋季依次减小的变化趋势,冬、春季节海水呈现不同程度石油污染,夏、秋季节属Ⅰ、Ⅱ级水质,整个流沙湾海域表层海水石油烃的平面分布相对比较均匀。在内外湾分布上,冬、春、秋季节外湾大于内湾,而夏季节内湾大于外湾。流沙湾的水产养殖活动是其海水石油烃时空分布的主要影响因素。  相似文献   

19.
Soil microbes in temperate forest ecosystems are able to cycle several hundreds of kilograms of N per hectare per year and are therefore of paramount importance for N retention. Belowground C allocation by trees is an important driver of seasonal microbial dynamics and may thus directly affect N transformation processes over the course of the year. Our study aimed at unraveling plant controls on soil N cycling in a temperate beech forest at a high temporal resolution over a time period of two years, by investigating the effects of tree girdling on microbial N turnover. In both years of the experiment, we discovered (1) a summer N mineralization phase (between July and August) and (2) a winter N immobilization phase (November-February). The summer mineralization phase was characterized by a high N mineralization activity, low microbial N uptake, and a subsequent high N availability in the soil. During the autumn/winter N immobilization phase, gross N mineralization rates were low, and microbial N uptake exceeded microbial N mineralization, which led to high levels of N in the microbial biomass and low N availability in the soil. The observed immobilization phase during the winter may play a crucial role for ecosystem functioning, since it could protect dissolved N that is produced by autumn litter degradation from being lost from the ecosystem during the phase when plants are mostly inactive. The difference between microbial biomass N levels in winter and spring equals 38 kg N/ha and may thus account for almost one-third of the annual plant N demand. Tree girdling strongly affected annual N cycling: the winter N immobilization phase disappeared in girdled plots (microbial N uptake and microbial biomass N were significantly reduced, while the amount of available N in the soil solution was enhanced). This was correlated to a reduced fungal abundance in autumn in girdled plots. By releasing recently fixed photosynthates to the soil, plants may thus actively control the annual microbial N cycle. Tree belowground C allocation increases N accumulation in microorganisms during the winter which may ultimately feed back on plant N availability in the following growing season.  相似文献   

20.
于2009年2月-8月利用高效液相色谱法对徐州市区冬、春、夏3个季节大气TSP和PM10中16种多环芳烃进行分析,结果表明:大气TSP和PM10中∑PAHs不同季节分布规律均为:冬季〉春季〉夏季;冬季,荧蒽污染浓度最高;春季和夏季苯并(g,h,i)芘浓度最高;不同环数PAHs春季和年均值呈规律均为:6环〉4环〉5环〉3环〉2环;夏季为:6环〉5环〉4环〉3环〉2环;冬季为:4环〉5环〉6环〉3环〉2环;大气TSP中整体苯并(a)芘等效致癌毒性(BEQ)不同季节分布规律为:冬季(4.517ng/m3)〉夏季(1.602ng/m3)〉春季(1.413ng/m3);PM10中整体BEQ不同季节分布规律为:冬季(3.706ng/m3)〉春季(1.504ng/m3)〉夏季(1.331ng/m3);采暖期大气颗粒物中PAHs污染对人体健康危害风险相对较高。  相似文献   

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