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Macroinvertebratess as Indicators of the Water Quality of an Urbanized Stream Kaduna Nigeria
M.C. Emere,C.E. Nasiru
Journal of Fisheries International , 2012,
Abstract: A survey was conducted from March to September, 2005 on a fourth order perennial Northern Nigerian stream to evaluate the water quality using the macrobenthic invertebrate community of the bankroot biotope. Physico-chemical variables were determined using standard methods, A total of 1304 macroinvertebrates were recovered. Twenty-seven taxa were recorded. The higher number of taxa (23) was recorded at station 2. The abundance of individuals was highest at station 3. The presence of low densities of pollution tolerant macroinvertebrate groups, the deteriorating water quality and the physco-chemical conditions of the water during the dry season months was a reflection of organic pollution stress caused by decomposing domestic refuse and inorganic fertilizer washed into the stream by irrigation.
Understanding The Historic City= Tarihi ehiri Anlamak
Nuray ?zaslan
tasar?m + kuram , 2003,
Abstract: The primary aim of this paper is to develop anew perspective in the contemporary urbandesign problem of the historic city. It willargue that the city is not an object of ideologicaland economic choices but rather the subjectof architectural phenomenon. In this sense oneof the main differences between the pre-industrialand modern city is the role and appearanceof architecture. The lack of architecturalquality and duality appears because of discontinuityin the intrinsic rules of the city buildingitself which are the result of accumulatedarchitectural culture of its society as its makerand user. This paper is based on the argumentthat new interventions in those ancient citiesshould follow their own architectural rules,which can be grasped by careful analysis of theurban structure. Bu yaz n n konusu a da ba lamdaki tarihsel kentin gelece e ait tasar m sorununa yeni bir perspektif nermektir. Kent yap evresinin kompleks bir bi imi olarak mimarl k olgusunun ortas nda yer al r. Yaz n n temas n olu turan ‘ a da ba lam’ ve ‘tarihsel kent’ birbiriyle uzla maz g rünen temel olgulard r. Farkl sistemleri temsil eden bu iki kavram nesnel olarak da farkl yap lar tan mlar. Bu farkl l k kentsel doku ve g rünümde bir ikilik olarak ortaya kar. Bütünlü ünü ve giderek de mimar kimli ini yitiren tarihsel kentin gelece i nemli bir tasar m problemidir ayn zamanda. Bu yaz tarihsel kente yap lacak her türlü müdahale de tasar m belirleyeninin kentin kendi i sel kurallar olmas gerekti ini iddia eder ve bu kurallar n ke fini sa layacak bir y ntemin er evesini nerir.
Stream structure characteristics and their impact on storageand flood control capacity in the urbanized plain river network

YUAN Wen,YANG Kai,TANG Min,XU Qi-xin,

地理研究 , 2005,
Abstract: Stream structure in urbanized river network area has unique characteristics under the effect of physical factors and human modification. Hence the issues of what and how such changes worked on river network storage and flood control capacity become the focus of this study. Taking Shanghai as a sample area, which is one of the largest cities in China located in the eastern Yangtze Delta, by using Horton-Strahler classification and Horton laws as reference based on the stream classification system that is commonly adopted in Shanghai and other cities around it, this paper analyzed the stream structure characteristics in each catchment under various urbanization levels;approached the effect of urbanization on stream structure development; and demo nstrated the possible relations between stream structure and river network storage and flood control capacity. The flood storage and control functions of streams in each order were further discussed in this paper. The main results are: (1 ) The stream number and length within the river network were highly developed in the study area. Stream number developed better than stream length. (2) The stream structure could only be modified when urbanization was up to a certain high level. Physical laws still played important roles in those catchments with lower urbanization level. (3) The stream structure expressed the possible trends from comprehension to simplicity, from multiform to singleness during the process of urbanization. (4) There was an obvious converse change between river network storage and flood control capacity and urbanization level. River network stor age and flood control capacity was influenced both by the quantity of water area and stream structure and much more closely related to the number and length of streams in the lower order. (5) For those streams in the higher order, the stor age capacity was stronger than the control capacity and the converse situatione xisted in those streams in the lower order. (6) proper quantity of water area and better stream structure were the infrastructures to assure ecological flood storage and control in urban area.
Spatial Concentration Characteristics of Urban Land Use along Highways in Rapidly Urbanized Region of Shenzhen

LV Xiaofang,WANG Yanglin,PENG Jian,WU Jiansheng,

地理学报 , 2008,
Abstract: Land use and land cover change research needs to paid more attention to identify spatial characteristics. Spatial concentration characteristics of urban land use along highways, as an important economic corridor in rapidly urbanized region, are helpful to identify spatial pattern of economic activities and expanding rules of urban land use in the future. This paper analyzed the spatial concentration characteristics of urban land use pattern along highways in Shenzhen in 2005 by means of landscape pattern metrics and association rule of spatial data mining. The paper measured spatial statistical characters and neighborhood characteristics of urban land use pattern along main highways in three dimensions respectively, including single land use type, co-location land use types, and combined land use types. The results are as follows: Industrial area was the primary land use type along highways in Shenzhen. Export-oriented township enterprises accelerated the urbanization process of rural areas outside the special zone. The area of urban public facilities for education and medical treatment was comparatively small, which disturbed the harmony of urban economic functions generally. The landscape metrics of single land use type in all buffer belts presented particular distance-based character, and they also showed a gradually reducing trend. There were some semi-concentration centers, especially in the region 500-1000 meters away from highways, and this could be taken as an important spatial threshold for further research. Co-location distribution pattern showed that two different urban land use types are much closer in adjacent buffer belts near highways. Industrial areas are extremely concentrated in adjacent and much more long-distance buffer belts away from highways, and followed by the concentration of residential districts in the neighborhood. That phenomenon was extremely obvious outside the special zone in Shenzhen. Concerning spatial characteristics of combined land use types, this study indicated strong spatial autocorrelation of each urban land use type in the study area. The combinations of industrial area with other land use types were comparatively common, which reflected the spatial pattern of economic activities of main industrial areas in Shenzhen, especially outside the special zone, and presented the effects of local industrial cluster.
Potential Stream Density in Mid-Atlantic U.S. Watersheds  [PDF]
Andrew J. Elmore, Jason P. Julian, Steven M. Guinn, Matthew C. Fitzpatrick
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0074819
Abstract: Stream network density exerts a strong influence on ecohydrologic processes in watersheds, yet existing stream maps fail to capture most headwater streams and therefore underestimate stream density. Furthermore, discrepancies between mapped and actual stream length vary between watersheds, confounding efforts to understand the impacts of land use on stream ecosystems. Here we report on research that predicts stream presence from coupled field observations of headwater stream channels and terrain variables that were calculated both locally and as an average across the watershed upstream of any location on the landscape. Our approach used maximum entropy modeling (MaxEnt), a robust method commonly implemented to model species distributions that requires information only on the presence of the entity of interest. In validation, the method correctly predicts the presence of 86% of all 10-m stream segments and errors are low (<1%) for catchments larger than 10 ha. We apply this model to the entire Potomac River watershed (37,800 km2) and several adjacent watersheds to map stream density and compare our results with the National Hydrography Dataset (NHD). We find that NHD underestimates stream density by up to 250%, with errors being greatest in the densely urbanized cities of Washington, DC and Baltimore, MD and in regions where the NHD has never been updated from its original, coarse-grain mapping. This work is the most ambitious attempt yet to map stream networks over a large region and will have lasting implications for modeling and conservation efforts.
The width of ecological corridor in landscape planning

ZHU Qiang,

生态学报 , 2005,
Abstract: Ecological corridors have many functions such as biodiversity conservation, contamination filtration, erosion prevention and flood control. As an important element in landscape planning and design, ecological corridors can be used to reduce the negtative impact of landscape fragmentation. According to their different structures and functions, ecological corridors can be classified into linear, strip, and stream corridors. The planning and design of ecological corridors are mainly composed of several key elements including number, context, width, connectivity, component, key points and areas. The width of ecological corridors is usually an uncertain parameter depending on the complexity of the structures and functions of the ecological corridors themselves, and it is the function of a number of parameters such as target species, vegetation, functions of corridors, surrounding land uses and length of corridors. Scientific and appropriate width of ecological corridors should be determined based on the research of defferent ecological processes within the corridor. Starting from the analysis of the structure and function of landscape, this review analyzed the width of ecological corridors and its determinants from the perspective of biodiversity conservation; appropriate ranges of width were summarized from several case studies. Principles to define width were also proposed.
Environmental analysis in the zone of Corridor X in Serbia  [PDF]
Miljanovi? Dragana N.,Kova?evi?-Majki? Jelena,Milanovi? Ana
Glasnik Srpskog Geografskog Dru?tva , 2004, DOI: 10.2298/gsgd0402165m
Abstract: This article treats the environmental issues and their intimate relationship with social and economic reality in the zone of Pan-European multimodal transport Corridor X in Serbia. On the basis of data of environmental elements quality (water, air and land) carried out assessment of environmental status.
Impressions of Serbia: Tourists on cruises along Corridor 7
Dragin Aleksandra S.,Bubalo-?ivkovi? Milka,?ur?ev Branislav S.
Glasnik Srpskog Geografskog Dru?tva , 2009, DOI: 10.2298/gsgd0902135d
Abstract: This paper deals with cruises along Corridor 7 and the tourist offer of Serbia. The purpose of the paper has been to establish how international tourists see our country during their travels across Serbia on cruises along Corridor 7. The research has been based on the interviews with international tourists who participated in land tours while cruising through Serbia. The interviews, together with the structured questionnaire, were conducted from March to November 2007 with the objectives to establish the following: the structure of the respondents according to the country of origin, gender and age structure, as well as the social and economic structure; what their motives are for cruising along Corridor 7; what is their perception of the value obtained through the tourist product and services during the Corridor 7 cruises and during their stay in Serbia (what they liked best in Serbia; if they were dissatisfied with anything in terms of the tourist offer of Serbia; to what extent their visit complemented or influenced their personal impressions of this country - what their impressions were before and after the visit). The importance of this paper, above all, is in broadening our knowledge about the adequacy of the tourist offer in Serbia in the tourism segment which is the subject of study of the paper.
Landscape ecological characteristics in temporal changes of riverside open space in urbanized area
Shigeru Tanimoto
,N. Nakagoshi

环境科学学报(英文版) , 1999,
Abstract: --The aim of this paper is to clarify the pattern andprocess of changes of landscape in riverside open spaces inurbanized area. The area between the old banks of the FurukawaRiver in Hiroshima City was examined in this research. The land-use maps of the study area were drawn at seven different times wereanalyzed, and the number, sizes and perimeters of all patches of all land-use types were measured. In these areas, temporalpatterns of land-use change over the past 30 yers were divided tothree stages 1966-1976, 1976-1988 and 1988-1997. As a result ofhuman disturbance, the riparian forest patches in urbanized areashave decreased in average size and have also become longer andnarrower.
Aerul ?i Apa : Componente ale Mediului , 2012,
Abstract: The role of the hydrological factor in habitat dynamics within the fluvial corridor of Danube. This paper had explored the connections between river hydrology with its changes and habitat dynamics. The fluvial corridor integrates spatially the channel and parts of its floodplain affected by periodical flooding and could be considered as an ecological corridor because of the size of the hydrosystem. The river and its ecosystems depend on geomorphogenetic and biological function and, thus creating a inter-dependence transposed into a concept, namely the fluvial hydrosystem, proposed firstly by Roux 1982, Amoros 1987. The hydrosystem is an ecological complex system constituted of biotopes and specific biocenoses of stream waters, stagnant water bodies, semi-aquatic, terrestrial ecosystems localized in the space of floodplain modeled directly and indirectly by river’s active force.
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