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1.
城市绿地类型的划分及其在生态城市建设中的意义和作用 总被引:3,自引:1,他引:3
根据生境和绿地功能把城市绿地划分为10个类型,并阐述了这些类型的组建和管护问题。10个绿地类型包括保护区,植物园,城市公园,城市片林,街心花园、草坪和花坛,道路两旁绿化区,庭园绿地,房顶、墙壁、凉台和室内的绿化,村落生态经济园及生态农业景观。根据归属部门、管理级别、保护对象、管理对象及监控类型的不同,对保护区进行了进一步的划分。城市绿地分类系统的建立既能把城市建设与生物多样性保护相结合,也有助于生物多样性公约的实施,并在维护城市生态安全、美化城市环境、建立具有特色的生物多样性产业、开展生态旅游和生态教育培训、繁荣地方经济和提高当地人民生活水平等方面有重要意义。 相似文献
2.
湖北省主要城市园林绿地土壤养分评价 总被引:1,自引:0,他引:1
根据湖北城市地形,对2个山地城市(恩施、十堰)、3个丘陵城市(荆门、襄樊、宜昌)和6个平原城市(武汉、孝感、咸宁、荆州、随州、黄石)绿地土壤进行采样.每个城市又按照4种不同利用类型,包括公园绿地、住宅区、事业单位(包括学校、医院、政府机关等)和交通主干道绿地分别取样.结果表明:湖北省主要城市绿地土壤pH较自然土壤明显偏高,均值7.9;土壤有机质(6.8g·kg-1)明显处于缺乏水平;有效N、P、B含量处于较低水平;其他中微量元素(Ca、Mg、S、Fe、Cu、Mn、Zn和B)有效态含量适中.土地利用方式对平原城市土壤养分含量影响显著,住宅区绿地土壤pH显著高于公园、街道旁和事业单位,街道绿地微量元素S、Cu、Mn、Zn有效态含量显著高于其他利用类型,公园绿地养分含量最低.不同地形城市土壤养分含量存在显著差异,平原城市土壤有机质、铵态氮、有效K、有效P和许多中微量养分元素(Ca、Mg、S、Fe、Cu和Mn)的含量显著高于丘陵城市. 相似文献
3.
The loss of urban green space as a result of urbanization threatens the overall biodiversity of urban areas, and prompts us to consider the importance of existing urban nature more carefully. Because urban ecological systems are in intense interaction with human-social systems, it is fruitful to create an interdisciplinary research and planning framework to ensure the maintenance of biodiversity in urban areas. For this purpose, we adapted a suitable theoretical and conceptual scheme for the setting of Finnish urban development, which provides an example of a situation where a lot of nature has so far remained inside and around urban area. The adapted scheme focuses on the land use change as a result of urban land use planning and development, and may provide a way to address the important variables and feedback mechanisms between information flowing from ecological systems and drivers from the social system. Furthermore, we outlined a more specific framework around the Finnish urban detailed planning process in order to study the interactions between these systems further. After addressing ecology-oriented questions of quantity, quality and needs of urban nature, and human-oriented drivers, such as flow and incorporation of information, knowledge, values and institutions, we identified several challenges in integrating the components of ecological and social systems. Creating common conceptual ground for different actors and disciplines, improving communication in the process, matching contradictory values and perceptions, and improving stakeholder participation would be in the best interest of nature and people of urban areas. 相似文献
4.
基于遥感的广州市城市绿地生态服务功能评价 总被引:2,自引:0,他引:2
利用TM卫星影像数据和野外观测数据,运用遥感定量反演模型和知识,提取影响广州市城市绿地生态服务功能的地表参数,如叶面积指数、植被指数、土壤水、地表反照率、地表温度等,然后利用神经网络技术实现对单一因子的城市绿地生态服务功能的评价与分级;在此基础上,利用模糊聚类法对广州市城市绿地生态服务功能进行综合评价。结果表明:广州市城市中心绿地生态服务功能偏弱;绿地在各区分布差异较大,空间布局不够合理。生态服务功能一级的城市绿地面积为2.1km2,仅占研究区域总面积的0.4%,生态服务功能二级、三级和四级的绿地面积占研究区域总面积的比例分别为2.4%、5.0%和2.9%。 相似文献
5.
Yuno Do Ji Yoon Kim Gu-Yeon Kim Gea-Jae Joo 《Landscape and Ecological Engineering》2014,10(2):277-284
In a closed landfill, we investigated the diversity and ecological characters of carabid beetles to understand the ecological importance of closed landfills that have the potential as a multi-functional habitat for improving biodiversity in urbanized areas. In addition, we studied the influence of environmental factors (vegetation structure, soil) on distribution and diversity of carabid beetles. A total of 92,495 individuals representing 15 carabid species were collected from the closed landfill. Although the species richness of carabid beetles recorded in the closed landfill was not higher than the other green spaces in the city, the closed landfill could sufficiently provides a stable habitat as a semi-natural area for carabid beetles. Soil pH, Na, and tall grass plant cover influenced carabid assemblage in the closed landfill. However, other environmental variables (e.g., K+, Na+, Mg2+, bare land cover, weedy cover, and tree cover) were not correlated with carabid species composition. It is implied that in the closed landfill, which is a highly modified engineered environment, other abiotic environmental (e.g., drainage, soil texture, leachate, and landscape context, etc.) and biotic factors (e.g., intra- and interspecific competition) may have affected carabid assemblage. Although artificial drainages are essential facilities for landfill management, they are a critical factor that affects the species inhabiting the landfill. However, carabid beetles seemed to randomly fall into the artificial drainage. For successful management of closed landfills, it is very important that minimize the intervention and that develop the ecological sensitively management method. 相似文献
6.
Th. Dornieden A. A. Gorbushina W. E. Krumbein 《International biodeterioration & biodegradation》2000,46(4)
Mural paintings and stone monuments are exposed to natural and man-made hazards for time spans sometimes longer than 10,000 years without total decay. On the other hand, a high percentage of the mineral physical heritage suffers severe damage and even total loss within a few decades. Several factors influence this general situation. The mural paintings of Lascaux and Altamira had been stabilized in a protective environment for millennia until they were re-exposed to severe environmental risks. Wall paintings and stone sculptures may remain unaltered for many years through: (1) stabilized and protective environments, (2) development of a protective patina (biofilm, minerals, organics) or, (3) more recent additional paint or mortar layers, which themselves are exposed to environmental hazard instead of the fresco underneath. Natural or artificial coverage, however, will invariably hinder evaluation and appreciation of the object of art. Detrimental microorganisms often only sporadically interact with these precious paintings. Many microbes settling on and in mural paintings are of a unusual metabolic type, namely poikilotrophic organisms. These poikilotrophs are capable of forming a biocoenosis on and in mural paintings, which may establish itself within a few months or years and then remains unchanged in a dormant or non-cultivable state for many years, or even centuries. The same holds true for chemical and physical alterations brought about by microorganisms. After a damaging initiation period of growth, the microflora may turn into a biofilm, which continues to live at extremely low levels of metabolic activity. In this way, detrimental chemical, physical and biological activities may be screened or shielded off for a very long period of time. In order to understand these processes, we have studied poikilotroph sub-aerial biofilms of mural paintings and sculptures excavated after long periods of dormancy. Several methods for the characterization of the physical properties of the colonies of fungi involved in colonization and deterioration of mural paintings and stone monuments are described. The fairy-tale of “The Sleeping Beauty” maybe an excellent metaphor for this phenomenon. The main issue, however, is to understand the physical or mechanical impact of the poikilotroph flora on the materials of the physical heritage studied. 相似文献
7.
Clarita Rodríguez-Soto Alejandro Velazquez Octavio Monroy-Vilchis Pricila Lemes Rafael Loyola 《Biodiversity and Conservation》2017,26(8):1899-1918
The objective of the present paper is to provide a holistic framework to delineate “territories of opportunity” where agrarian communities can manage areas to enhance the conservation of large vertebrates. The study was conducted Mexico, which is sociologically, culturally and ecologically complex, similar to other “megadiverse” countries. We conducted ensemble niche modeling of endangered top predators to define a set of large vertebrate species. Environmental attributes were used to perform three distance-based and two artificial intelligence-based algorithms. Socio-cultural attributes were included to depict agricultural communities with strong social government schemes and clear evidence of well-managed natural resources. Other socio-economic attributes such as land acquisition cost, human agglomeration and anthropogenic land use were included in the analysis. Scenarios were computed and displayed cartographically with the aid of a geographic information system. Results showed that the largest concentration of biodiversity converges on regions with large land cover persistence and high local governance, defined as potential willingness to engage in conservation actions. The cartographic areas identified overlapped with current Mexican protected areas in only 2.7% of the country. Thus, conservation law enforcement in most of the country seems to be ineffective. Here we show that, in a number of territories, agrarian communities that have coexisted for millennia with umbrella species can be regarded as allies in biodiversity conservation. Results are discussed in the light of their relevance for future niche modeling, environmental policy design and implications for climate change. 相似文献
8.
A combined approach of remote sensing (RS) and geographical information systems (GIS) was used in this study to identify the impact on urban surface radiant temperature (SRT) of urban green-space change. Urban SRT increases as green-space area is converted into non-green-space area. Also, well preserved green space and newly connected green space contribute to a decrease of the SRT. Seoul Metropolitan area is rapidly expanding. Existing urban SRT studies have, however, mainly been conducted for Seoul City. The most rapidly expanding area in Korea is now the Seoul suburban area, for example the Mt Gwanggyo area. Although changes of SRT and normalized difference vegetation index (NDVI) as a result of land-use change have been measured in many other studies, the results in these studies were derived from data from different seasons. Also, these studies did not examine a newly expanding area. Considering these problems, the same seasonal multitemporal data were used in this study to derive the SRT change for the same season in different years. This study confirmed the importance of effective management and location of urban green space for urban SRT mitigation. Ultimately, the impact on urban SRT of urban green-space change should be regarded as an important factor in urban planning. 相似文献
9.
Montemayor Sara I. Besteiro Sebastián I. del Río M. Guadalupe 《Biodiversity and Conservation》2022,31(7):1969-1986
Biodiversity and Conservation - The Chaco and Pampean provinces in the Neotropical region are highly disturbed by intensive forestry and livestock raising. This study is an integrative approach... 相似文献
10.
S. J. BRENTNALL D. J. BEERLING C. P. OSBORNE M. HARLAND† J. E. FRANCIS† P. J. VALDES‡ V. E. WITTIG§ 《Global Change Biology》2005,11(12):2177-2195
Polar forests once extended across the high‐latitude landmasses during ice‐free ‘greenhouse’ intervals in Earth history. In the Cretaceous ‘greenhouse’ world, Arctic conifer forests were considered predominantly deciduous, while those on Antarctica contained a significantly greater proportion of evergreens. To investigate the causes of this distinctive biogeographical pattern, we developed a coupled model of conifer growth, soil biogeochemistry and forest dynamics. Our approach emphasized general relationships between leaf lifespan (LL) and function, and incorporated the feedback of LL on soil nutrient status. The model was forced with a mid‐Cretaceous ‘greenhouse’ climate simulated by the Hadley Centre GCM. Simulated polar forests contained mixtures of dominant LLs, which reproduced observed biogeographical patterns of deciduous, mixed and evergreen biomes. It emerged that disturbance by fire was a critical factor. Frequent fires in simulated Arctic ecosystems promoted the dominance of trees with short LLs that were characterized by the rapid growth and colonization rates typical of today's boreal pioneer species. In Antarctica, however, infrequent fires allowed trees with longer LLs to dominate because they attained greater height, despite slower growth rates. A direct test of the approach was successfully achieved by comparing modelled LLs with quantitative estimates using Cretaceous fossil woods from Svalbard in the European Arctic and Alexander Island, Antarctica. Observations and the model both revealed mixed Arctic and evergreen Antarctic communities with peak dominance of trees with the same LLs. Our study represents a significant departure from the long‐held belief that leaf habit was an adaptation to warm, dark winter climates, and highlights a previously unrecognized role for disturbance (in whatever guise) in polar forest ecology. 相似文献
11.
Theocharis D. Zagas Dimitrios I. RaptisDimitrios Th. Zagas 《Ecological Engineering》2011,37(2):286-293
Rural development in forested lands and high altitude ecosystems created new regimes and disturbances that set protective function of forests as the most fundamental of all forest functions. Considering protective forests as engineering structures against natural hazards and risks, such as erosion, able to replace costly manmade infrastructures, a methodology is presenting aiming at their spatial identification in a changing mountainous environment. The methodology followed is based on field observations, calibrated models, topographical, geological and climatic data as well as human presence indicators combined properly in a GIS environment. Analysis showed that some forest soils are prone to erosion hazard unable to absorb disturbances like selective logging, revealing the protective role of their forest cover. The spatial identification of the forests with a particular protective function is the necessary step required for the design of a sustainable management of high elevated ecosystems. 相似文献
12.
13.
1. The influence of leaf thickness on internal conductance for CO2 transfer from substomatal cavity to chloroplast stroma ( g i ) and carbon isotope ratio (δ13 C) of leaf dry matter was investigated for some evergreen tree species from Japanese temperate forests. g i was estimated based on the combined measurements of gas exchange and concurrent carbon isotope discrimination.
2. Leaves with thicker mesophyll tended to have larger leaf dry mass per area (LMA), larger surface area of mesophyll cells exposed to intercellular air spaces per unit leaf area ( Smes ) and smaller volume ratio of intercellular spaces to the whole mesophyll (mesophyll porosity).
3. gi of these leaves was correlated positively to S mes but negatively to mesophyll porosity. The variation in g i among these species would be therefore primarily determined by variation of the conductance in liquid phase rather than that in gas phase.
4. δ13 C was positively correlated to mesophyll thickness and leaf nitrogen content on an area basis. However, g i values did not correlate to δ13 C. These results suggest that difference in δ13 C among the species was not caused by the variation in g i , but mainly by the difference in long-term photosynthetic capacity.
5. Comparison of our results with those of previous studies showed that the correlation between leaf thickness and gi differed depending on leaf functional types (evergreen, deciduous or annual). Differences in leaf properties among these functional types were discussed. 相似文献
2. Leaves with thicker mesophyll tended to have larger leaf dry mass per area (LMA), larger surface area of mesophyll cells exposed to intercellular air spaces per unit leaf area ( S
3. g
4. δ
5. Comparison of our results with those of previous studies showed that the correlation between leaf thickness and g
14.
Autotrophic methanogens reduce CO2 to CO and assimilate CO in a carbonylation reaction. Heterotrophic species were found not to form CO and/or to incorporate CO into cell matiral. The absence of CO formation correlated with the absence of carbon monoxide dehydrogenase activity. The heterotrophic Methanobrevibacter ruminantium, Methanobrevibacter smithii, Methanococcus voltae and Methanospirillum hungatei (strain GP 1) were investigated. 相似文献
15.
Abdel-Wahab A. Abdel-Warith El-Sayed M.I. Younis Nasser A. Al-Asgah 《Saudi Journal of Biological Sciences》2016,23(3):404-409
This study aimed to evaluate the effects of diet containing the green macroalgae, Ulva lactuca, on the growth performance, feed utilization and body composition of African catfish Clarias gariepinus. Four experimental diets were formulated: D1 as a control group and D2, D3 and D4 which included 10%, 20% and 30% U. lactuca meal, respectively. 180 African catfish, weighing 9.59 ± 0.43 g, and with an average length of 11.26 ± 0.21, (mean ± SE) were divided into four groups corresponding to the different feeding regimes. The final body weight of the fish showed insignificant differences (P > 0.05) between the control and fish fed D2, whereas, there was a significant difference (P < 0.05) between these two diets compared with D3 and D4, with weights of 70.52, 60.92, 40.57 and 35.66 g recorded for D1, D2, D3 and D4, respectively. In the same trend significant differences were also evident in weight gain, specific growth rate and feed utilization. Fish fed with a diet containing 20% or 30% U. lactuca meal had poorer growth performance and feed utilization. Protein productive value, protein efficiency ratio, daily dry feed intake and total feed intake were also significantly lower in fish fed with D3 and D4 than in the control D1 and D2.Overall, the results of the experiment revealed that African catfish fed a diet with U. lactuca included at 20% and 30% levels showed poorer growth and feed utilization than the control group and fish fed diets containing 10% of U. lactuca. 相似文献
16.
M. -J. Gaillard H. J. B. Birks U. Emanuelsson B. E. Berglund 《Vegetation History and Archaeobotany》1992,1(1):3-17
An on-going, integrated project concerning modern pollen/vegetation/land-use relationships in south Sweden is outlined. Some preliminary results and their potential uses in palaeoecological reconstructions are discussed. Moss polsters were collected from 92 examples of vegetation/land-use areas of south Sweden (e.g. nonfertilized grazed areas, burned and grazed heaths, traditionally managed fodder-producing meadows, etc.). A total of 23 land-use (e.g. management type) and environment variables (e.g. soil chemistry) is available for 84 sites. The 84 sample data-set was analysed by canonical correspondence analysis and associated statistical testing using Monte Carlo permutation tests to explore and test patterns of modern pollen variation in relation to the environment, and by weighted averaging regression and calibration to derive local-scale environmental and land-use reconstructions from fossil pollen assemblages preserved in a soil profile. 相似文献
17.
18.
Anna Maria Mercuri Marta Bandini Mazzanti Paola Torri Luigi Vigliotti Giovanna Bosi Assunta Florenzano Linda Olmi Isabella Massamba N’siala 《Vegetation History and Archaeobotany》2012,21(4-5):353-372
Integration of pollen data from both marine and terrestrial cores contributes to the understanding of the timing of the climatic and human forces that shaped the cultural landscapes in the Italian peninsula. This paper focuses on the relation between natural and human landscapes, and the development of the cultural landscape from the Bronze Age to the medieval period and modern times. Two records were studied within independent projects, first the marine core RF93-30, from the central Adriatic, with a sediment source area including the Po valley and which spans the last 7,000?years, and secondly, material from the site of Terramara di Montale, a Bronze Age settlement on the Po plain, which was occupied from approximately 3550–3200?cal. b.p. The original chronology of the marine core was developed by using the magnetic inclination of the secular variation record and two 14C dates carried out on benthic and planktic foraminifera at depths of 527 and 599?cm. Its pollen record shows a gradual irreversible trend towards increasing aridity since 5700?cal. b.p. and, just after around 5100?cal. b.p., a Picea decline and a Quercus ilex type increase indicate less cool conditions. Human impact introduces rapid changes, such as the decrease of Abies alba, thinned by the reduction of precipitation and further cleared before or during the Early Bronze Age, followed by the fall of oaks. The latter started after around 3900?cal. b.p., and became evident at around 3600?cal. b.p. The gradual increase in signs of open landscape and woodland clearance correspond to the onset of Middle Bronze Age settlements in the Po valley, and to the development of the cultural landscape in the region. The impact of the terramare people includes woodland management by coppicing, and division of the territory into a patchwork of pastures and fields. Dry environments are indicated mainly by Cichorioideae, resulting from the continued human pressure, and these spread since the Recent Bronze Age. Of the possible causes for the decline of the terramare, we suggest that climate would have been less important in the decline than in the onset phases. The later cultural landscapes are mainly indicated by the trends of the Olea, Juglans and Castanea (OJC) records, besides those of cereals. At around 700?cal. b.p., the “chestnut landscape” spread while modern times are shown by the finds of Zea mays. 相似文献
19.
Glomski IJ Dumetz F Jouvion G Huerre MR Mock M Goossens PL 《Microbes and infection / Institut Pasteur》2008,10(12-13):1398-1404
Bacillus anthracis virulence is dependent on toxins and capsule. Encapsulation is associated with dissemination. We hypothesized that eliminating capsule would modify the portal of entry and the spread of bacteria. Using a bioluminescent model of inhalational anthrax, we demonstrated that aerosolized spores of a capsule-deficient strain administered at moderate doses initiated infection in the nasopharynx. Dissemination beyond the nasopharynx was delayed for at least 24h and then targeted the kidneys. Interestingly, high intranasal doses led to spore germination in the alveoli. We conclude that eliminating capsule while maintaining toxin production alters dissemination, but allows infection initiation in the lungs. 相似文献
20.
I?igo Zuberogoitia Jose Antonio Martínez Ainara Azkona Jose Enrique Martínez I?aki Castillo Jabi Zabala 《Journal of Ornithology》2009,150(1):95-101
Methods of evaluating population trends have recently received particular attention because of perceived declines in several
species during the twentieth century. We have studied demographic traits of the peregrine falcon (Falco peregrinus) population in Bizkaia (Northern Spain) for 11 years. This species suffered a severe decline in the 1950s and 1960s and started
to recover in the 1980s and 1990s, although the recovery trends differed between areas. In our study area the peregrine falcon
density is one of the highest found in Spain. The frequency of juvenile breeders was 2.0%, the mean age at first breeding
being 3.7 calendar years for males and 4.0 cy for females. The territorial fidelity was at least 3.4 years for males and 3.7 years
for females. Females dispersed on average 80.5 km and males 51.8 km during their pre-breeding movements, whilst distance between
birthplace and breeding territories was on average 108.5 km for females and 64.5 km for males. We studied the relationships
between adult turnover, recruitment age, territorial fidelity and dispersal in a healthy population in order to establish
population dynamics. A combination of these parameters, not just age at first breeding, could be used as a potential early
warning signal indicating future changes, prompting their consequences to be evaluated. This approach could lead to the reclassification
of the large-scale health of a population. Its utilization would allow resources to be directed into helping “ailing” subpopulations,
detecting causes of decline, and developing adequate recovery strategies. 相似文献