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Zvětrávání arsenopyritu v lesních půdách v acidifikovaném prostředí / Weathering of arsenopyrite in soils in acidified environmentSoukupová, Lenka January 2010 (has links)
Lenka Soukupová, Zvětrávání arsenopyritu v lesních půdách v acidifikovaném prostředí SUMMARY The weathering of arsenopyrite (FeAsS) has been studied at the experimental site Načetín in the Ore Mountains, Czech Republic. There were chosen three areas with different vegetation (beech, spruce a unforested areas) at this site. The arsenopyrite samples were placed in all soil horizons (litter, horizons A, B and C for forest areas; horizons A, B and C for unforested area), where they were exposed to ambient conditions for one year. After one-year weathering, the newly formed secondary minerals were identified and the rate of surface oxidation was determined, both depending on the environment of oxidation. Although physical-chemical parameters and content of main and trace elements of the studied soils varied, the only detected crystalline secondary mineral of arsenic was scorodite (FeAsO4∙2H2O). Nevertheless, this differences affected amount of formed scorodite. The highest concentrations were determined on the surface of the arsenopyrite grains that oxidized in the beech stand, conversely the lowest concentrations were determined on the arsenopyrite grains from the unforested area.
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Utilização de índices de vegetação para estimativa da proteção do solo pela cobertura vegetal : uma contribuição para o uso da equação universal das perdas de solo /Veniziani Junior, José Carlos Toledo. January 2003 (has links)
Orientador: Marcos César Ferreira / Banca: Sergio dos Anjos Ferreira Pinto / Banca: Diana Sarita Hamburger / Resumo: O processo de erosão acelerada se apresenta como um dos maiores problemas ambientais da atualidade, influenciando a produção agrícola, devido às conseqüências no empobrecimento do solo e no abastecimento de água, diminuindo a sua disponibilidade em reservatórios. Este trabalho apresenta uma proposta para avaliação da ambiental das variáveis relacionadas ao desenvolvimento de processos erosivos além da verificação da adequação do uso e ocupação do solo as necessidades especiais da área, tendo como estudo de caso a Bacia do Córrego Santo Antonio, situada no município de Jaú-SP. Propomos como indicador quantitativo da cobertura vegetal, os índices de vegetação (IV) obtidos por meio de imagens de satélite. Na avaliação da suscetibilidade à erosão nos amparamos no modelo da EUPS o qual foi desenvolvido para obtenção de uma classificação das terras da bacia em classes de risco de erosão além da obtenção classes de capacidade de uso relativas a cada unidade pedológica. O estudo relativo a analise da viabilidade da utilização do IV, foi embasado na amostragem de campo a partir da qual se obteve os valores médios de percentual de interceptação das gotas de chuva para determinados tipos de cultivo na região. Avaliamos ser possível o emprego do índice de vegetação em estudos referentes à proteção do solo e acreditamos serem as classes de risco á erosão um importante indicador das necessidades de planejamento ambiental. Verificamos uma mudança no uso do solo da área do ano 2000 para ao ano 2003, o que provocou grandes alterações nos resultados da adequação do uso do solo na bacia do córrego Santo Antonio. / Abstract: The soil loss process arises as one of the major environmental problems nowadays, influencing the agricultural production, due to its consequences on the soil decay and on the water supply, decreasing its availability in the reservoirs. This work presents a proposal for the assessment of the environmental aspect of the variables concerning the development of the soil loss processes besides the verification of the adequacy of the use and occupation of the land regarding the special necessities of the area, portraying as study of case the Santo Antonio watershed, located in the town of Jaú, São Paulo. We propose as the quantitative indicator of the vegetation covering, the vegetation indexes ( VI) obtained through satellite images. On the assessment of the soil loss susceptibility we looked for support on the USLE, which was developed to obtain a classification of the watershed lands in classes of soil loss risk, besides obtaining classes on the capability of use regarding each pedologic unit. The study about the analysis of the viability of the use of the vegetation index was based in the field samples, from which were achieved the average percentage values of rain drops interception for determined kinds of agricultural growing in the region. We assessed that it is possible to proceed the use of the vegetation index in studies concerning the soil protection, and we believe that the classes of risk regarding soil loss are an important indicator towards the necessities of environmental planning. It was verified a certain change on the land use in the area from the year 2000 until the year 2003, what brought huge alterations on the outcome of the land use adequacy in the Santo Antonio watershed. / Mestre
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Classification of Urban Forms and Their Relationship with Vegetation Cover in Cache County, UtahPeaden, Stephen J. 01 December 2019 (has links)
As residential urban development increases in the western United States, few studies have shown how different urban forms influence vegetation cover. The two studies in this thesis examine how to define and measure urban form in order to understand the relationship between urban form characteristics and vegetation cover.
In the first study, urban form was defined by using past methods of identifying and measuring urban sprawl. Past studies showed the most essential metrics that define residential urban form are building density, centrality, connectivity, land use mix, and parcel size. This study reviews these metrics and proposes revised unified definitions and measurement methods. It is recommended that consistent definitions and methods be used in further research of urban form.
Cache County, Utah was used as a study area to apply these methods as a representative community of the western U.S. Residential parcels were measured for each metric. A K-means cluster analysis assign each parcel to one of 50 groups based on metric measurement similarities. The 10 most widely used groups contained 87% of the residential parcels in Cache County. These groups represented urban forms with distinct identifiable characteristics such as Agricultural residential, urban sprawl, historic plat patterns, and evolved versions each.
The second study used the metrics and groups from the first study to check for correlations with vegetation cover. A normalized difference vegetation index ( NDVI) of aerial imagery of Cache County was used to classify land cover into three groups: dense vegetation, light vegetation, and no vegetation. Measurements of vegetation cover were extracted for each parcel and each urban form group. Total vegetation cover ( TVC) and dense vegetation cover (DVC) measured higher in urban areas than in the county as a whole. Agricultural residential groups had among the highest TVC, but had the lowest DVC. Non-agricultural residential groups had the highest DVC as a percentage of TVC with the exception of group 4 “Modern Suburban Sprawl” which had the lowest DVC as a percentage of TVC. Group 7 “Satellite Centers” had the highest TVC while group 3 “Dead End Semi-sprawl” had the lowest TVC. Both groups 3 and 7 had the highest DVC as a percentage of TVC.
A correlation analysis revealed that TVC had stronger correlations than DVC with urban form metrics. Building density had the strongest correlation with TVC (r = -0.62, p= 0). Correlations with TVC were also found with Parcel size (r = -0.23, p= <.001) and centrality (r = -0.21, p = <.001). Very weak relationships with TVC w ere found with connectivity and land use mix.
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Caracterização do uso do solo e das áreas de preservação permanente, visando a adequação ambiental /Marcussi, Aline Braga. January 2010 (has links)
Orientador: Teresa Cristina Tarlé Pissara / Banca: Sérgio Campos / Banca: Maurício José Borges / Resumo: A adequação ambiental em microbacias hidrográficas é importante para auxiliar no planejamento do desenvolvimento de nossa sociedade. Para eficácia e resultado da adequação é imprescindível que seja cumprida e respeitada a legislação ambiental brasileira em vigor, no contexto da unidade territorial na qual será desenvolvido o trabalho. A análise do uso e ocupação do solo em uma superfície é a primeira etapa para nortear uma gestão eficaz no que tange à adequação do meio, seja este rural ou urbano. O trabalho teve como principal objetivo caracterizar os padrões fotográficos que representem a avaliação do uso e ocupação do solo da cabeceira de drenagem da Microbacia do Córrego Rico, localizada no Município de Monte Alto, SP, para fins de adequação ambiental no que tange a legislação florestal brasileira. O mapeamento foi realizado utilizando técnicas de sensoriamento remoto e interpretação visual da imagem World View 1, seguida da digitalização da rede de drenagem e vegetações (naturais e agrícolas) no AutoCAD MAP 3D, com auxílio de documentos cartográficos e trabalho de campo. A área de estudo apresenta uma superfície de 2.141,53 ha e os resultados permitiram constatar que a principal cultura é a cana-deaçúcar, com 546,34 ha, seguida de pastagens com 251,22 ha, frutíferas com 191,71 ha, eucalipto com 57,31 ha e a cebola com 49,52 ha da área total, confirmando a presença dos canaviais na região. Analisou-se que a área em questão possui 375,04 ha de APPs e apenas 19,24% destas, compostas por mata ou vegetação arbórea nativa. Precisam ser enriquecidos e reflorestados 302,87 ha com vegetação nativa da região, de acordo com a Resolução SMA 08 de 2008... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The environmental suitability of watersheds is important for planning the development of our society. However, for the effective result of this action is necessary to consider the Brazilian environmental legislation, which must be respected, mainly in the territorial unit, where will be developed the field work. The analysis of the land use is the first step to guide an effective management, regarding the appropriateness of the rural and urban lands. This work aimed to define image patterns representing the photographic evaluation of the land uses of the Córrego Rico drainage net, located in Monte Alto, SP., for respecting the environmental legislation of Brazilian forest. Mapping was performed using remote sensing techniques and visual interpretation of the World View image, due to the drainage and vegetation (natural and agricultural) vetorization in AutoCAD Map 2008 software, looking at the cartographic documents and doing fieldwork. The study area has an extension of 2141.53 ha, and the results revealed that the main crop is sugar cane, with 546.34 ha; followed by pasture with 251.22 ha, perennial crops with 191.71 ha, eucalyptus with 57.31 ha and 49.52 ha of onion, confirming the progress of the sugar cane plantations in the region. It was noted also that the watershed has 375.04 ha of preserved areas along the drainage net, but only 72.17 ha (19.24% of the areas of permanent preservation) are made up by natural vegetation, and 302.87 ha of those need to be enriched and reforested with native vegetation, according to law. The study and analysis of the Córrego Rico watershed have the data for future proposals for models of environmental suitability in accordance with environmental regulations / Mestre
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Caracterização do uso do solo e das áreas de preservação permanente, visando a adequação ambientalMarcussi, Aline Braga [UNESP] 24 November 2010 (has links) (PDF)
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marcussi_ab_me_jabo.pdf: 4285785 bytes, checksum: f8eff1a838b7bf6d233a121ea5f1941d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A adequação ambiental em microbacias hidrográficas é importante para auxiliar no planejamento do desenvolvimento de nossa sociedade. Para eficácia e resultado da adequação é imprescindível que seja cumprida e respeitada a legislação ambiental brasileira em vigor, no contexto da unidade territorial na qual será desenvolvido o trabalho. A análise do uso e ocupação do solo em uma superfície é a primeira etapa para nortear uma gestão eficaz no que tange à adequação do meio, seja este rural ou urbano. O trabalho teve como principal objetivo caracterizar os padrões fotográficos que representem a avaliação do uso e ocupação do solo da cabeceira de drenagem da Microbacia do Córrego Rico, localizada no Município de Monte Alto, SP, para fins de adequação ambiental no que tange a legislação florestal brasileira. O mapeamento foi realizado utilizando técnicas de sensoriamento remoto e interpretação visual da imagem World View 1, seguida da digitalização da rede de drenagem e vegetações (naturais e agrícolas) no AutoCAD MAP 3D, com auxílio de documentos cartográficos e trabalho de campo. A área de estudo apresenta uma superfície de 2.141,53 ha e os resultados permitiram constatar que a principal cultura é a cana-deaçúcar, com 546,34 ha, seguida de pastagens com 251,22 ha, frutíferas com 191,71 ha, eucalipto com 57,31 ha e a cebola com 49,52 ha da área total, confirmando a presença dos canaviais na região. Analisou-se que a área em questão possui 375,04 ha de APPs e apenas 19,24% destas, compostas por mata ou vegetação arbórea nativa. Precisam ser enriquecidos e reflorestados 302,87 ha com vegetação nativa da região, de acordo com a Resolução SMA 08 de 2008... / The environmental suitability of watersheds is important for planning the development of our society. However, for the effective result of this action is necessary to consider the Brazilian environmental legislation, which must be respected, mainly in the territorial unit, where will be developed the field work. The analysis of the land use is the first step to guide an effective management, regarding the appropriateness of the rural and urban lands. This work aimed to define image patterns representing the photographic evaluation of the land uses of the Córrego Rico drainage net, located in Monte Alto, SP., for respecting the environmental legislation of Brazilian forest. Mapping was performed using remote sensing techniques and visual interpretation of the World View image, due to the drainage and vegetation (natural and agricultural) vetorization in AutoCAD Map 2008 software, looking at the cartographic documents and doing fieldwork. The study area has an extension of 2141.53 ha, and the results revealed that the main crop is sugar cane, with 546.34 ha; followed by pasture with 251.22 ha, perennial crops with 191.71 ha, eucalyptus with 57.31 ha and 49.52 ha of onion, confirming the progress of the sugar cane plantations in the region. It was noted also that the watershed has 375.04 ha of preserved areas along the drainage net, but only 72.17 ha (19.24% of the areas of permanent preservation) are made up by natural vegetation, and 302.87 ha of those need to be enriched and reforested with native vegetation, according to law. The study and analysis of the Córrego Rico watershed have the data for future proposals for models of environmental suitability in accordance with environmental regulations
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Satellite Estimates of Tree and Grass Cover Using MODIS Vegetation-Indices and ASTER Surface-ReflectanceMr Tony Gill Unknown Date (has links)
No description available.
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Active and Passive Coastal Pavement DegradationHyatt, James Andrew 04 1900 (has links)
<p> Inland degradational trends of coastal dolomite pavements (on the Amabel formation near Tobermory Ontario Map 1) were examined in three wave energy settings: passive, intermediate, and active shores. </p> <p>Six pavement property trends were examined to determine the effect of low fetch lengths (7-10 km - Ford 83) and long shallow wave approach (Map 1) on the break-up of passive coastal pavements (south-west Bear's Rump Island): vegetation cover , grike dimensions, fracturing, pitting, shattering and flaking, and soil and rubble depths. </p> <p> Detailed analysis of small scale surface solution features, "karren", was undertaken at five 1 m sample grids on the intermediate average fetch 70-90 km -Grosset 85) Cyprus Lake provincial park pavements. </p> <p> / Thesis / Bachelor of Arts (BA)
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The effect of climate on vegetation cover in Swedish mountain regions / Klimatpåverkan på vegetationen i det svenska fjällområdetEkman, Malin January 2019 (has links)
Climate change, with a higher temperature, is making the snow covered period shorter in the Swedish mountain region. This represents a threat towards plant species at high altitudes which, due to their sensitivity to temperature changes, will likely lead to a change in plant species composition. The purpose of this study was to determine if there has been any change in vegetation cover in the Swedish mountain region and if temperature has changed, based on data from a long-term monitoring program called National Inventory of Landscapes in Sweden (NILS), and data collected from the Swedish Meteorological and Hydrological Institute (SMHI). The NILS program has conducted three different inventories from 2003 – 2018 in which Sweden is divided into 10 stratums. Further, NILS divided Sweden into 631 survey quadrates (5x5 km), which of 145 were distributed across the Swedish mountain region. Linear regression analysis was used to determine if there had been any change in the average vegetation cover, or in the cover of lichens, mosses and herbs, and to assess if there had been any change in temperature during the sample years 2003 – 2018. The results showed that the vegetation cover in both the sample blocks of 20 m radius and smaller sample areas 0.252 m had no significant change. Neither did the cover of herbs or the average temperature. The period of 2003 – 2018 might have been too short of a period to see any kind of difference in the temperature and the herbs might have a difficult time surviving due to a long drought period and hence they have not been able to increase their average cover. Results of lichens and mosses showed a significant increase in cover which could be because they can withstand drought better than herbs and therefore have a better chance of surviving the rise in temperature. In conclusion I observed no change in the cover of vegetation but there is an increasing cover of lichens and mosses in the Swedish mountain regions. / Klimatförändring med en högre temperatur leder till att den snötäckta perioden är kortare i det svenska fjällområdet. Detta är ett hot mot växtarter som redan befinner sig på gränsen av sin extrema klimatzon och kommer med stor sannolikhet leda till en förändring i kompositionen av växtarter. Syftet med denna studie var att fastställa om det har blivit någon förändring i vegetationstäcket i det svenska fjällområdet och om det finns en förändring i temperaturen med hjälp av data från Nationell Inventering av Landskapet i Sverige (NILS) och data insamlat av Sveriges Meteorologiska och Hydrologiska Institut (SMHI). NILS programmet har i dagsläge utfört inventering vid 3 olika perioder fördelade mellan 2003 – 2018 och dom har delat upp Sverige i 10 olika stratum där stratum 10 är fjällområdet. Vidare har dom delat in Sverige i 631 inventerings rutor, varav 145 ligger i fjällområdet. Lineär regression analys användes för att se om det blivit någon förändring i täckningen av vegetationen, lavar, mossor och örter, samt för att se om temperaturen förändrats under inventeringsåren 2003 – 2018. Resultatet av täckningen på vegetationen i 20 m radie samt de små provområdena på 0,252 visade inte någon antydan på signifikant skillnad. Det gjorde inte heller resultatet på täckningen av örter eller medeltemperaturen. 2003 – 2018 kan ha varit alldeles för kort för att avgöra om det har blivit någon förändring i medeltemperaturen och örter kan ha de svårare att överleva då torrperioden blivit längre på grund utav den kortare snötäckta perioden. Mossor och lavar hade dock båda en ökning i sin täckning vilket kan förklaras med att många arter kan lagra vätska under en lång tid och har därmed en större chans att överleva en stigande temperatur. Slutsatsen är att sedan 2003 förekommer det inte någon förändring i vegetationstäcket, däremot finns det en ökad täckning av lavar och mossor i det svenska fjällområdet.
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Análise das características socioambientais na cidade de Belém/PA: um estudo da vegetação e clima urbano / Environmental and social analysis of characteristics in Belém city, Pará: a study of vegetation and urban climateRodrigues, José Edilson Cardoso [UNESP] 24 January 2017 (has links)
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Previous issue date: 2017-01-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nas últimas décadas, o rápido crescimento das cidades ocasionou modificações substanciais na paisagem urbana, fazendo com que passassem a gerar suas próprias condições ambientais, as quais, nem sempre, são favoráveis à população. Uma das modificações observadas é a geração do clima urbano, pois a cidade altera o clima principalmente na micro e meso escala, por meio das transformações da superfície, ocasionando o aumento de temperatura, variação da precipitação, modificação do fluxo dos ventos e da umidade do ar. Outra grande modificação observada na paisagem urbana é a redução da Cobertura Vegetal, que exerce diversas funções no âmbito social, estético e climático, amenizando a temperatura e umidificando o ambiente urbano. O interesse pelo estudo da interação entre cobertura vegetal e clima urbano da cidade de Belém-PA ocorreu a partir de observação da redução que a vegetação sofreu, o que pode ter impactado significativamente na temperatura intraurbana, com o consequente registro de aumento nas últimas décadas. O principal objetivo da pesquisa foi realizar um estudo relacionando à redução da cobertura vegetal e a mudança nos padrões de temperatura na área que consiste a Primeira Légua Patrimonial da cidade de Belém-PA. A metodologia adotada por nós abarcou uma análise teórica conceitual, tendo como método de análise o hipotético-dedutivo, adotando como referencial teórico o Sistema Clima Urbano, proposto por Monteiro (1976), com ênfase no subsistema termodinâmico. Nos procedimentos realizou-se levantamento cartográfico, uso de imagens termais, mapeamento da Cobertura Vegetal, para levantamento de Índice de Cobertura Vegetal (ICV), Índice de Cobertura Vegetal por habitante (ICV/hab.), mapeamento do uso do solo, levantamento das temperaturas, espacial e temporal, com base nos dados do INMET, de miniestações fixas, transectos e trabalho de campo para registros e observações. Assim, o que se constatou é que a perda da Cobertura Vegetal em Belém é considerada um processo histórico em função do processo de ocupação da cidade. Analisando o ICV por Distrito, o DABEL (9,41%) apresentou o melhor índice, seguido pelo DASAC (5,66%) e DAGUA (3,37%). A análise temporal da temperatura revelou uma tendência de crescimento considerável, ao longo das décadas. A partir das imagens termais, as temperaturas dos alvos sofreram oscilações, principalmente em alguns bairros localizados mais ao norte e ao sul da Légua. Bairros com pouca vegetação apresentaram temperaturas mais elevadas em relação a bairros com arborização considerável. Portanto a perda da cobertura vegetal na área da Primeira Légua, associada às elevadas temperaturas, revelou um quadro ambiental preocupante, sobretudo em bairros que apresentaram ICV baixo e alta densidade de construções, o que refletiu diretamente no aumento da temperatura nesses bairros. / In recent decades the rapid growth of cities has caused substantial changes in the urban landscape, making start to generate their own environmental conditions and which are not always favorable to the population. One of the changes observed is the urban climate generation, because the city changes the climate mainly in micro and meso scale, through the surface changes causing the temperature rise, precipitation change, the winds flow modification and humidity. Another major change observed in the urban landscape is the reduction of vegetation cover, which performs various functions in the social, aesthetic and climatic context softening temperature and humidifying the in the urban environment and other. Interest in the study of the interaction between vegetation and urban climate of the city of Belém-PA, due to the reduction that vegetation has suffered and may have a significant impact on intra-urban temperature that has seen an increase in recent decades. Thus, the main objective was to conduct a study relating to the reduction of the vegetation cover and the change in temperature patterns in the area that is the First League Balance of Belém-PA. The methodology embraced a conceptual theoretical analysis, with the method of the hypothetical-deductive analysis, adopting as a theoretical reference the urban climate system proposed by Monteiro (1976), emphasizing the thermodynamic subsystem. In proceedings conducted cartographical survey, use of thermal images, mapping of vegetation cover for lifting Vegetation Cover Index (VCI) and Vegetation Cover Index by Inhabitant (VCI / I), land use mapping, survey of temperature, time and space from INMET data, fixed mini-stations, transects and field work for records and observations. Thus, it was found that the loss of plant cover in Belém has been considered a historical process due to the city occupation process. Looking for VCI District, the DABEL (9.41%) had the highest rate, followed by DASAC (5.66%) and DAGUA (3.37%). The time temperature analysis showed a considerable growth trend over the decades and from thermal images the temperature of targets experienced fluctuations, especially in some neighborhoods located further north and south of League. Neighborhoods with little vegetation had higher temperatures compared to neighborhoods with large trees. Therefore, the loss of plant cover in the First League area associated with high temperatures has revealed a worrying environmental framework, particularly in neighborhoods that had VCI low and high density buildings which is directly reflected in the increase in temperature in these neighborhoods.
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Modelling Vegetation Cover Types Using Multiseasonal Remotely Sensed Data to Compare Ecotones at Multiple Spatial and Spectral ResolutionsPatraw, Kimberly 01 May 1997 (has links)
The Army National Guard Bureau has implemented a cooperative project with Utah State University to help with the use, display, and evaluation of environmental data for maintaining land condition. Camp Grayling, Michigan, is comprised of deciduous and evergreen forest types. Use of remote sensing for classification has been limited in this region due to the difficulty of species-level classification using single-date remote-sensing techniques . Also, remote sensing has traditionally focused on mapping homogenous zones rather than vegetation boundaries, while one of the concerns for land managers is the nature of vegetation edges (ecotones).
This study analyzed each season and band from multiseasonal satellite imagery for their contribution to separating vegetation type and density classes. Then spectral reflectance values for each vegetation and density class were used in discriminant models that define vegetation cover types and densities. These models were then tested against points within 200 m of vegetation boundaries to determine the performance of the models at edges of vegetation types . The reflectance values for vegetation types on Landsat Thematic Mapper (TM), Landsat MultiSpectral Sensor (MSS), and Advanced Very High Resolution Radiometer (AVHRR) imagery were used.
Single-band separability decreased with decreasing resolution of the remote sensing data, and the number of spectral bands that could separate means of vegetation and density cover classes was much greater than expected . Winter bands provided more separability than expected for density classes . A VHRR data were shown to provide very little separation and were not included in the discriminant analysis. In the evaluation of the discriminant models, both resubstitution and crossvalidation tests showed that TM and MSS were nearly equal in their ability to discriminate cover types and densities.
At the vegetation boundary zones, classification accuracy increased with increasing distance from the edge. These results are encouraging for future classification and monitoring of ecotones using satellite imagery, as picture elements (pixels) of ecotones generally exhibit the characteristics of a mixing of the boundary vegetation types. Further investigation into fuzzy set classification and ecotone classification and monitoring appears warranted.
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