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The Integration of Vegetation in Architecture, Vertical and Horizontal Greened Surfaces  [cached]
Katia Perini,Adriano Magliocco
International Journal of Biology , 2012, DOI: 10.5539/ijb.v4n2p79
Abstract: Greening the building envelope is a rapidly developing field in the words of ecology, horticulture and built environment, since it’s an opportunity for combining nature and buildings (linking different functionalities) in order to address environmental issues in dense urban surroundings. A green envelope is a good opportunity for improving the urban environment conditions, since European cities tend to be densely built, becoming the scene of important environmental issues relative to pollution in the atmosphere. Vegetation allows improving the air quality, incrementing biodiversity and reducing urban heat islands thanks to its cooling and refreshing capacity, beside an aesthetical value. The massive integration of vegetation in architecture allows exploiting the surface (both horizontal and vertical) of the buildings to obtain the benefits mentioned above and, consequently, an improvement in environmental quality and inhabitants’ wellbeing. This paper discusses the environmental benefits achievable with the integration of vegetation in built space, the main characteristics of green envelope elements and typologies connected to theirs functional and formal peculiarity, to the contribution on the building envelope performances and to environmental and economical aspects.
Seroprevalence of malaria in inhabitants of the urban zone of Antananarivo, Madagascar
Olivier Domarle, Romy Razakandrainibe, Emma Rakotomalala, Laurence Jolivet, Rindra Randremanana, Fanjasoa Rakotomanana, Charles Ramarokoto, Jean-Louis Soares, Frédéric Ariey
Malaria Journal , 2006, DOI: 10.1186/1475-2875-5-106
Abstract: Serological studies specific for P. falciparum were carried out with an indirect fluorescent antibody test (IFAT). In a representative population of Antananarivo, 1,059 healthy volunteers were interviewed and serum samples were taken.The seroprevalence of IgG+IgA+IgM was 56.1% and that of IgM was 5.9%. The major risk factor associated with a positive IgG+IgA+IgM IFAT was travel outside Antananarivo, whether in the central highlands or on the coast. The abundance of rice fields in certain urban districts was not associated with a higher seroprevalence.Malaria transmission levels are low in Antananarivo, but seroprevalence is high. Humans come into contact with the parasite primarily when travelling outside the city. Further studies are required to identify indigenous risk factors and intra-city variations more clearly.Antananarivo, the capital of Madagascar, is located on hills in the middle of the Central Highlands, at an altitude of between 1,200 and 1,400 m. The city and its surroundings include 1,700,000 inhabitants (2001 census), corresponding to about 10% of the national population. The Antananarivo plain is covered by vast areas of irrigated rice fields, which are potential breeding sites for malaria vectors. Some of the seedier districts in the middle of town have zones that flood easily, favouring mosquito breeding. At the beginning of the 1980s, Anopheles funestus reappeared in the Central Highlands of Madagascar [1-3], from which it had disappeared in the 1950s [4]. New epidemic episodes appeared in the middle of the 1980s [5-7], causing several tens of thousands of deaths [8]. Two surveys carried out in Antananarivo in 2003 showed, by biological examinations, that less than 2% of all cases of fever were confirmed to be malaria. About 80% of the confirmed cases had travelled outside the city to areas exposed to malaria in the weeks preceding the survey, the remaining 20% of cases being cases of indigenous malaria due to local transmission [9]. Imported cas
Urban Vegetation Mapping from Fused Hyperspectral Image and LiDAR Data with Application to Monitor Urban Tree Heights  [PDF]
Fatwa Ramdani
Journal of Geographic Information System (JGIS) , 2013, DOI: 10.4236/jgis.2013.54038
Abstract:

Urban vegetations have infinite proven benefits for urban inhabitants including providing shade, improving air quality, and enhancing the look and feel of communities. But creating a complete inventory is a time consuming and resource intensive process. The extraction of urban vegetation is a challenging task, especially to monitor the urban tree heights. In this study we present an efficient extraction method for mapping and monitoring urban tree heights using fused hyperspectral image and LiDAR data. Endmember distribution mapping using the spectral angle mapper technique is employed in this study. High convenience results achieved using fused hyperspectral and LiDAR data from this semiautomatics technique. This method could enable urban community organizations or local governments to map and monitor urbans tree height and its spatial distribution.

Landscape ecological analysis of urban vegetation in Guangzhou, China
Guan Dong-sheng,WANG Li-rong,Li Zhen,
Guan Dong sheng
,Wang Li rong,Li Zhen

环境科学学报(英文版) , 1999,
Abstract: --The compositions, patches and landscape heteorogentity ofGuangzhou urban vegetation are studied by using the principles oflandscape ecology in this paper. The results showed that the areaof urban vegetation was 26901.4hm2, and the distribution ofvegetation types and regional vegetation coverage were uneven. Thepatch areas of vegetation were large in scenery vegetation andshelter vegetation, and small in street corner vegetation and smallgarden vegetation. Most of patches fell in range between 100 and10000 m2. Only 1.13% of patches were larger than 1000000 m2. Structure features of vegetation landscape in old urban ares weresmall patch, high scattering degree, high diversity, randomdistribution of vegetation patches and high heterogeneity. In newurban areas, the features were big patches, fine planning, mediumlandscape heterogeneity. At last, some suggestions are madeaccording to landscape character of Guangzhou urban vegetation.
Comparing Different Approaches for Mapping Urban Vegetation Cover from Landsat ETM+ Data: A Case Study on Brussels  [PDF]
Tim Van de Voorde,Jeroen Vlaeminck,Frank Canters
Sensors , 2008, DOI: 10.3390/s8063880
Abstract: Urban growth and its related environmental problems call for sustainable urban management policies to safeguard the quality of urban environments. Vegetation plays an important part in this as it provides ecological, social, health and economic benefits to a city’s inhabitants. Remotely sensed data are of great value to monitor urban green and despite the clear advantages of contemporary high resolution images, the benefits of medium resolution data should not be discarded. The objective of this research was to estimate fractional vegetation cover from a Landsat ETM+ image with sub-pixel classification, and to compare accuracies obtained with multiple stepwise regression analysis, linear spectral unmixing and multi-layer perceptrons (MLP) at the level of meaningful urban spatial entities. Despite the small, but nevertheless statistically significant differences at pixel level between the alternative approaches, the spatial pattern of vegetation cover and estimation errors is clearly distinctive at neighbourhood level. At this spatially aggregated level, a simple regression model appears to attain sufficient accuracy. For mapping at a spatially more detailed level, the MLP seems to be the most appropriate choice. Brightness normalisation only appeared to affect the linear models, especially the linear spectral unmixing.
Comparing Different Approaches for Mapping Urban Vegetation Cover from Landsat ETM+ Data: A Case Study on Brussels
Tim Van de Voorde,Jeroen Vlaeminck,Frank Canters
Sensors , 2008,
Abstract: Urban growth and its related environmental problems call for sustainable urban management policies to safeguard the quality of urban environments. Vegetation plays an important part in this as it provides ecological, social, health and economic benefits to a city ¢ € s inhabitants. Remotely sensed data are of great value to monitor urban green and despite the clear advantages of contemporary high resolution images, the benefits of medium resolution data should not be discarded. The objective of this research was to estimate fractional vegetation cover from a Landsat ETM+ image with sub-pixel classification, and to compare accuracies obtained with multiple stepwise regression analysis, linear spectral unmixing and multi-layer perceptrons (MLP) at the level of meaningful urban spatial entities. Despite the small, but nevertheless statistically significant differences at pixel level between the alternative approaches, the spatial pattern of vegetation cover and estimation errors is clearly distinctive at neighbourhood level. At this spatially aggregated level, a simple regression model appears to attain sufficient accuracy. For mapping at a spatially more detailed level, the MLP seems to be the most appropriate choice. Brightness normalisation only appeared to affect the linear models, especially the linear spectral unmixing.
Thermal based functional evaluation of urban park vegetation
John Bosco NJOROGE,Akihiro NAKAMURA,Yukihiro Morimoto,
John Bosco NJOROGE
,Akihiro NAKAMURA,Yukihiro MORIMOTO

环境科学学报(英文版) , 1999,
Abstract: --An evaluation of the urban park vegetation was conductedby integrating airborne multispectral scanning system (MSS) thermalband data with meteorological. MSS data acquired in the morning andafternoon were utilized to assess the radiant energy budget ofdifferent ground cover types and its relationship with the surfacetypes. The spatial distribution of surface temperature (Ts) andsurface albedo (A) varied between different surfaces. However, thespatial variability of net radiation (Rn) was reduced by negativefeedback of A-Ts relationship. The Normalized Difference Vegetation Index (NDVI) had a negative correlation with Ts but positivelycorrelated to Rn of the different surface types. Thermal responsenumber (TRN), which expresses the dissipative behavior of radiantenergy, correctly characterized each ground cover type according tothe validated surface property. Forested and lawn covered sites hadthe highest TRN values consistent with their tendency to resistmicroclimatic change. The approach shows that by utilizing the MSSthermal signatures, we can relate the microenvironment processes tothe biophysical character of each site offering an opportunity todiagnose site-specific problems. The approach is proposed as adirect and easily adaptable method for monitoring the urban greenpark areas and for making objective decisions about theirmanagement.
ASSESSMENT OF ENVIRONMENTAL CONDITIONS ON THE BASIS OF HEAVY METAL CONCENTRATION IN URBAN SOIL AND VEGETATION Оценка состояния окружающей среды по содержанию тяжелых металлов в почве и растительности города
Ivanova R. R.
Polythematic Online Scientific Journal of Kuban State Agrarian University , 2012,
Abstract: The assessment results of urban environmental conditions on the basis of accumulation of heavy metals in the soil and vegetation are presented. The questions about the ability of different plants to accumulate heavy metals in the lives are discussed as well
Inclusion of vegetation in the Town Energy Balance model for modelling urban green areas
A. Lemonsu, V. Masson, L. Shashua-Bar, E. Erell,D. Pearlmutter
Geoscientific Model Development (GMD) & Discussions (GMDD) , 2012, DOI: 10.5194/gmd-5-1377-2012
Abstract: Cities impact both local climate, through urban heat islands and global climate, because they are an area of heavy greenhouse gas release into the atmosphere due to heating, air conditioning and traffic. Including more vegetation into cities is a planning strategy having possible positive impacts for both concerns. Improving vegetation representation into urban models will allow us to address more accurately these questions. This paper presents an improvement of the Town Energy Balance (TEB) urban canopy model. Vegetation is directly included inside the canyon, allowing shadowing of grass by buildings, better representation of urban canopy form and, a priori, a more accurate simulation of canyon air microclimate. The surface exchanges over vegetation are modelled with the well-known Interaction Soil Biosphere Atmosphere (ISBA) model that is integrated in the TEB's code architecture in order to account for interactions between natural and built-up covers. The design of the code makes possible to plug and use any vegetation scheme. Both versions of TEB are confronted to experimental data issued from a field campaign conducted in Israel in 2007. Two semi-enclosed courtyards arranged with bare soil or watered lawn were instrumented to evaluate the impact of landscaping strategies on microclimatic variables and evapotranspiration. For this case study, the new version of the model with integrated vegetation performs better than if vegetation is treated outside the canyon. Surface temperatures are closer to the observations, especially at night when radiative trapping is important. The integrated vegetation version simulates a more humid air inside the canyon. The microclimatic quantities (i.e., the street-level meteorological variables) are better simulated with this new version. This opens opportunities to study with better accuracy the urban microclimate, down to the micro (or canyon) scale.
Inclusion of vegetation in the Town Energy Balance model for modeling urban green areas
A. Lemonsu,V. Masson,L. Shashua-Bar,E. Erell
Geoscientific Model Development Discussions , 2012, DOI: 10.5194/gmdd-5-1295-2012
Abstract: Cities impact both local climate, through urban heat islands, and global climate, because they are an area of heavy greenhouse gas release into the atmosphere due to heating, air conditioning and traffic. Including more vegetation into cities is a planning strategy having possible positive impacts for both concerns. Improving vegetation representation into urban models will allow to address more accurately these questions. This paper presents an improvement of the TEB urban canopy model. Vegetation is directly included inside the canyon, allowing shadowing of grass by buildings, better representation of urban canopy form, and, a priori, a more accurate simulation of canyon air microclimate. The development is performed so that any vegetation model can be used to represent the vegetation part. Here the ISBA model is used. The model results are compared to microclimatic and evaporation measurements performed in small courtyards in a very arid region of Israel. Two experimental landscaping strategies – bare soil or irrigated grass in the courtyard – are observed and simulated. The new version of the model with integrated vegetation performs better than if vegetation is treated outside the canyon. Surface temperatures are closer to the observations, especially at night when radiative trapping is important. The integrated vegetation version simulates a more humid air inside the canyon. The microclimatic quantities are better simulated with this new version. This opens opportunities to study with better accuracy the urban microclimate, down to the micro (or canyon) scale.
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