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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

A plant association classification for McDonald-Dunn Forest /

Hubbard, Connie J. January 1991 (has links)
Thesis (M.S.)--Oregon State University, 1991. / Includes mounted photographs. Typescript (photocopy). Includes bibliographical references (leaves 134-143). Also available on the World Wide Web.
22

Spatio-temporal analyses of woody vegetation cover using remote sensing techniques: the case of Alice - King Williams Town route, Eastern Cape, South Africa

Fundisi, Emmanuel January 2016 (has links)
Expansion of woody vegetation results in the transformation of a grass-dominated ecosystem to a tree-dominated ecosystem causing land degradation in most semi-arid areas. The imbalance in the natural ecosystem between herbaceous plants and woody vegetation poses a threat to the natural environment. Such changes alter the flow, availability and quality of nutrient resources in the biogeochemical cycle. Most of the dominating woody plants are often unpalatable to domestic livestock. Therefore, the objective is to assess the spatial extent of woody vegetation over time. Knowledge of the spatial and temporal characteristics of woody vegetation dynamics will enable the development of management plans. These characteristics can be derived using remote sensing techniques which have become efficient in such studies. This study aimed to characterize woody vegetation dynamics along the route between Alice and King Williams’s town in Eastern Cape Province South Africa using Landsat data. This aim was achieved by focussing on three specific objectives. The first objective was to compare the performance of multispectral data and Normalized Difference Vegetation Index (NDVI) data of Landsat imagery in mapping woody vegetation cover. The second objective was to investigate the effect of the spatial resolution of remotely-sensed data on discrimination of woody vegetation from other land cover types. The third objective characterised woody vegetation dynamics between 1986 and 2013/2014 using the results from the first objective. The study used Landsat imagery acquired in November or February of 1986, 1994/1995, 2002/2003 and 2013/2014. Due to lack of data which covered the study area two separate dates (November and February) where used for the study resulting in naming the study area western and eastern parts. Unsupervised classification was performed on the multispectral, NDVI and pan-sharpened images to generate four generic land cover classes, namely water, bare land, grassland and woodland. Accuracy assessments of the classified images was done using error matrix. The results showed that the classification based on NDVI images yielded a better overall accuracy than the classification based on multispectral images for the western (83 percent and 75 percent, respectively) and eastern (82 percent and 76 percent, respectively) parts of the study area. Similarly, pan-sharpening resulted in better overall classification accuracy than multispectral, but comparable to the classification of the NDVI images for both the western (82 percent) and eastern (83 percent) parts of the study area. Remote sensing is an effective tool in assessing changes in the physical environment. Landsat imagery is suitable in assessing land cover dynamics given the long-term and free availability of the image. In addition, the large spatial coverage it provides, enables Landsat data to be used on studies that have wide spatial coverage. Classification for the purpose of time-series analysis was then performed on the NDVI images of each date (1986, 1994/1995, 2002/2003 and 2013/2014). Both woody vegetation and grassland experienced changes from 1986 to 2013/2014 with grassland occupying (75 percent) compared to woodland (17 percent) in 1986. In the year 2013/14 grassland occupied 32 percent and woodland occupied 51 percent of the study area. The increase in woody vegetation in the study area can be attributed to livestock rearing and migration of people from the rural to urban areas post-Apartheid. The study output will aid in the development of a database on land cover distribution of the area between King William’s town and Alice town, providing useful information to decision-making and further studies on woody vegetation.
23

A família Myrtaceae na Floresta Nacional de Ipanema, Iperó, São Paulo, Brasil / The family Myrtaceae at Nacional Forest of Ipanema, Iperó, São Paulo, Brasil

Silva, Alan Teixeira da 10 June 2014 (has links)
Submitted by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-11T14:47:31Z No. of bitstreams: 1 SILVA_Alan_Teixeira_2014.pdf: 3906752 bytes, checksum: 3a963b186e1d5fbf49c4b78c34b7eb5e (MD5) / Approved for entry into archive by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-11T14:47:40Z (GMT) No. of bitstreams: 1 SILVA_Alan_Teixeira_2014.pdf: 3906752 bytes, checksum: 3a963b186e1d5fbf49c4b78c34b7eb5e (MD5) / Approved for entry into archive by Maria de Lourdes Mariano (lmariano@ufscar.br) on 2017-01-11T14:47:48Z (GMT) No. of bitstreams: 1 SILVA_Alan_Teixeira_2014.pdf: 3906752 bytes, checksum: 3a963b186e1d5fbf49c4b78c34b7eb5e (MD5) / Made available in DSpace on 2017-01-11T14:47:56Z (GMT). No. of bitstreams: 1 SILVA_Alan_Teixeira_2014.pdf: 3906752 bytes, checksum: 3a963b186e1d5fbf49c4b78c34b7eb5e (MD5) Previous issue date: 2014-06-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / With about 1.000 species and 23 genera occurring in Brazil, Myrtaceae is one of the most important families in floristic surveys, mainly in Cerrado and Atlantic Forest areas. The National Forest of Ipanema is occupied mostly by Atlantic Forest and small areas of Cerrado; it is also possible to observe signs of human exploration in the past in the area. The main objective of this work is to improve the knowledge of Myrtaceae in the National Forest of Ipanema. For this, field trips were made between September 2012 and March 2013 and the collections of the following herbaria were analyzed: CCTS, ESA, IAC, SP, SPSF, UEC. After data analysis 23 species of Myrtaceae and 6 genera were found: Eugenia (10 species), Myrcia (4 species), Psidium (4 species), Campomanesia (3 species), Calyptranthes (1 species) and Plinia (1 species). Descriptions, illustrations, maps of geographical distribution and keys of identification of the species were prepared. After data analyzis C. neriiflora was identified in the IUCN red list of threatened species as vulnerable risk, by the other side, Psidium guajava occurs at high frequency, as it is an invasive species, it could endanger the local biodiversity. All the collected specimens were deposited in CCTS collection. / Com aproximadamente 1.000 espécies e 23 gêneros ocorrentes no Brasil, Myrtaceae é uma das famílias mais representativas em levantamentos florísticos, principalmente em áreas de Cerrado e Mata Atlântica. A Floresta Nacional de Ipanema é ocupada predominantemente por Mata Atlântica e pequenas áreas de Cerrado, também é um local que já sofreu ações antrópicas de desmatamento no passado. O objetivo deste trabalho foi contribuir para o conhecimento da família Myrtaceae na Floresta Nacional de Ipanema. Para isso foram realizadas coletas no período de setembro de 2012 a março de 2013 e consultadas as coleções dos seguintes herbários: CCTS, ESA, IAC, SP, SPSF, UEC. Após análise dos dados foram identificadas 23 espécies de Myrtaceae distribuídas em 6 gêneros: Eugenia (10 espécies), Myrcia (4 espécies), Psidium (4 espécies), Campomanesia (3 espécies), Calyptranthes (1 espécie) e Plinia (1 espécie). Foram preparadas descrições, ilustrações, mapas de distribuição geográfica e chaves analíticas de identificação das espécies. Também foi constatado que C. neriiflora está presente na lista vermelha de espécies ameaçadas da IUCN em estado de risco vulnerável, entretanto, Psidium guajava ocorre com elevada frequência e por se tratar de uma espécie invasora foram alertados sobre os problemas que representa para a biodiversidade local. Todo material coletado foi depositado na coleção do CCTS.
24

Vegetation description and mapping along a strip transect in central Namibia with the aid of satellite imagery

Strohbach, Marianne Margarethe 02 August 2007 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc (Botany))--University of Pretoria, 2007. / Plant Science / MSc / unrestricted
25

The Feasibility of Using LANDSAT Thematic Mapper Data for Fine Scale Vegetation Classification in Southern Ontario

Hawes, Michael 04 1900 (has links)
<p> An analysis was performed using LANDSAT Thematic Mapper digital imagery to determine the feasibility of fine scale vegetation classification in southern Ontario. </p> <p> MICROPIPS, an image processing program, was used to analyse the Thematic Mapper data, based on spectral response patterns of different land cover types. Final classified images were compared with vegetation classifications as determined by the Royal Botanical Gardens, in Hamilton, Ontario. </p> <p> It was concluded, that it was possible to classify land cover types using MICROPIPS, but only at a general level. Thus, it was not feasible to classify vegetation on a fine scale. </p> / Thesis / Candidate in Philosophy
26

A floristic study of a former land bridge in The Bahama Archipelago

Daniels, Mark Leo 04 August 2016 (has links)
No description available.
27

Classification of vegetation of the South African grassland biome

Ellery, William Nolan January 1992 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg 1992. / The aim of the study was to develop understanding of the relationships between vegetation types of the grassland biome of South Africa and the environment, with an emphasis on structural and functional characteristics. The grassland biome in South Africa has traditionally been divided into 'pure' grasslands, assumed to be climatically determined, and 'false' grasslands of recent anthropogenic origin. A review of literature from several disciplines including palaeobotany, archaeology, ecology and biogeography indicates that this is not a valid distinction. It is clear that the distribution of the grassland biome as a whole is poorly understood, but the general correlation between the distribution of biomes and climate elsewhere in the world suggests that this warrants more detailed investigation. A water balance approach was used to develop climatic incices that both predict the distribution of grasslands, and are easy to interpret biologically. The indices are the mean. number of days per annum when moisture is available for plant growth, tbe mean temperature on days when moisture is available for plant growth (wet season temperature),. and the mean temperature when moisture is not available for plant growth (dry season temperature). Based on these three.indices the grassland biome in South Africa call be distinguished from neighbouring biomes. The fynbos and succulent karoo biomes have rainfall in winter. The grassland, nama-karoo and savanna biomes have' rainfall in summer. The forest biome experiences rainfall throughout the year. Of the summer rainfall biomes, the quantity of water available in the grassland biome b greater than in the nama-woo, similar to savanna, but less than forest. Grasslands experience cooler dry season temperatures than savannas. The localised distribution of woody plants within the. grassland biome suggests that it is the effect of climate on the fire regime that may be of overriding importance h'l determining the distribution of the biome as a whole. Woody elements are restricted to sites that are either protected from fire, or experience fires of lower intensity than sites that support- grassland, The unifying feature of the grassland biome is its proneness to fire. The presence of a warm, moist season promotes plant production and leads to a high standing crop close to the ground. The prolonged dry season causes vegetation to dry out annually, rendering it flammable. More arid biomes have plants more widely spaced, making it difficult for fire to spread. In more mesic biomes where rainfall is less sea.sonal than in the grasslands or savannas, fuels do not dry out sufficiently to ignite, A number of additional climatic features may promote burning in the grassland biome, It has the highest lightning density of all South Africa's biomes. 'tVarm, dry 'berg' winds desiccate fuels and 1 omote burning in the more mesic grasslands, The 'curing' of the grass sward due to dry season frost and temperature drop is important in establishing early dry season flammability. Savanna trees are fire tolerant, but they appear sensitive to the cold temperatures prevaient in the grassland biome in. the dry season, The relationship between the distribution of functional characters of grassland plants and environmental conditions was investigated. The distincrion between sweetveld, mixed veld and sourveld was recognised as one of the most Important functional features of South Africa's grasslands, The distribution of these vegetation types was examined in detail. Sweetveld occurs In warm, dry areas; sourveld in cool, moist areas. There Is overlap between these tyP.Js that Is dependant on soil nutrient status. Sweetveld that occurs in climatic conditions that would be expected to support mixed veld and sourveld, is on soils derived from basic parent material, including basalt, dolerite, gabbro and norite. Similarly, sourveld that occurs in areas that climatically would be expected to support sweetveld, is on soils derived from acid parent material such as sandstone and quartzite .. Soil nutrients that are most highly correlated to the occurrence of these three veld types are phosphoms availability and an index of nitrogen mineralization potential. 'l'here is an increase in bot; available phosphorus and the index of readily mineralizable nitrogen from sourveld to mixed veld to sweetveld. These features am inc01).10111tedinto a conceptual model that relates the distribution of these grassland types to carbon and nitrogen metabolism, with the role of phosphorus either similar to nitrogen, or else it may act indirectly by affecting the. rate of nitrogen mineralization, Nitrogen mineralization OCcursat lower water availability than carbon assimilation, and its temperature optimum is higher than that of carbon assimilation. Where nitrogen mineralization is favoured ielative to carbon assimilation, sweetveld is likely to (}C(.1\Xr. Where carbon assimilation is. favoured relative to; nitrogen mineralization, sourveld is likely to occur ....Soil texture affects the balance between these two processes in the degree to wm.r;h it protects soil organic matter, and thereforv the size of the nitrogen and ph_QSPllO_rOll.S pools. Changes in the rlj,stribution of South Africa's b~\omesfor a scenario of climate change are predicted using the biome model developed in this study. This illustrates the value of developing predictive models. / MT2017
28

Status i vremenska dinamika flore i vegetacije Deliblatske peščare / Status and temporal dynamics of the flora and vegetation of the Deliblaot Sands

Ćuk Mirjana 27 September 2019 (has links)
<p>U&nbsp; radu&nbsp; je&nbsp; analizirana&nbsp; flora&nbsp; i&nbsp; vegetacija&nbsp; Deliblatske pe&scaron;čare. Cilj istraživanja bio je utvrđivanje&nbsp; recentnog stanja&nbsp; i&nbsp; osnovnih&nbsp; karakteristika&nbsp; flore&nbsp; Deliblatske pe&scaron;čare,&nbsp; ali&nbsp; i&nbsp; analiza&nbsp; dinamike&nbsp; flore&nbsp; Deliblatske pe&scaron;čare u poslednjih 220 godina. Jedan od ciljeva je bila analiza sukcesivnih promena u flori i vegetaciji Deliblatske&nbsp; pe&scaron;čare&nbsp; i&nbsp; predikcija&nbsp; njihovog&nbsp; pravca&nbsp; i kvaliteta,&nbsp; kao&nbsp; i&nbsp; utvrđivanje&nbsp; diverziteta&nbsp; i sintaksonomske &scaron;eme vegetacije Deliblatske pe&scaron;čare uz klasifikaciju problematičnih vegetacijskih grupa u &scaron;irem aspektu- na nivou čitave Srbije, ali i Pontskog i Panonskog regiona. Terenska istraživanja su vr&scaron;ena u periodu&nbsp; 2012-2018&nbsp; godine.&nbsp; Floristički&nbsp; podaci&nbsp; su uzimani&nbsp; na&nbsp; istim&nbsp; lokalitetima&nbsp; kao&nbsp; i&nbsp; fitocenolo&scaron;ki snimci.&nbsp; Ukupno&nbsp; je&nbsp; uzeto&nbsp; 282&nbsp; fitocenolo&scaron;ka&nbsp; snimka metodom po Braun-Blankeu. Za florističku analizu je<br />obrađena&nbsp; 301&nbsp; referenca,&nbsp; a&nbsp; na&nbsp; terenu&nbsp; su&nbsp; prikupljeni podaci&nbsp; za&nbsp; 440&nbsp; vrsta,&nbsp; od&nbsp; kojih&nbsp; je&nbsp; 6&nbsp; po&nbsp; prvi&nbsp; put registrovano na ovom području. U florističku analizu je uključeno&nbsp; ukupno prikupljenih&nbsp; 9.887&nbsp; podataka. U radu je dat floristički pregled u vidu spiska taksona koji&nbsp; su&nbsp; zabeleženi&nbsp; na&nbsp; Deliblatskoj&nbsp; pe&scaron;čari&nbsp; (ima&nbsp; ih 1072),&nbsp; sa&nbsp; lokalitetima&nbsp; na&nbsp; kojima&nbsp; su&nbsp; do&nbsp; sada pronađeni,&nbsp; obeleženi&nbsp; su&nbsp; prvi&nbsp; nalazi&nbsp; za&nbsp; vrste&nbsp; i<br />podvrste, a obeležene su i vrste koje su potvrđene na terenskim&nbsp; istraživanjima&nbsp; u&nbsp; okviru&nbsp; ove&nbsp; disertacije. Floristička&nbsp; analiza&nbsp; je&nbsp; realizovana&nbsp; klasičnim numeričkim&nbsp; metodama,&nbsp; u&nbsp; cilju&nbsp; prezentacije najzastupljenijih&nbsp; familija,&nbsp; rodova,&nbsp; životnih&nbsp; formi&nbsp; i<br />horotipova.&nbsp; Predstavljene&nbsp; su&nbsp; endemične,&nbsp; reliktne&nbsp; i ugrožene&nbsp; i&nbsp; ivnazivne&nbsp; vrste&nbsp; Pe&scaron;čare.&nbsp; Na&nbsp; Deliblatskoj pe&scaron;čari je zabeleženo 16 endemskih, 22 reliktnih, 49 strogo&nbsp; za&scaron;tićenih,&nbsp; 8&nbsp; iz&nbsp; Crvenje&nbsp; knjige&nbsp; flore&nbsp; Srbije&nbsp; i 54&nbsp; invazivna&nbsp; taksona.&nbsp; Dinamika&nbsp; florističkih istraživanja&nbsp; je&nbsp; predstavljena&nbsp; analizom&nbsp;&nbsp; literaturnih podataka i dinamike istraživanja ovog područja, a u skladu&nbsp; sa&nbsp; značajnim&nbsp; dru&scaron;tvenim&nbsp; promenama područja,&nbsp; od&nbsp; kojih&nbsp; se&nbsp; kao&nbsp; najznačajniji&nbsp; momenat izdvaja&nbsp; početak&nbsp; po&scaron;umljavanja&nbsp; Pe&scaron;čare.&nbsp; U&nbsp; pregledu vegetacije&nbsp; Deliblatske&nbsp; pe&scaron;čare&nbsp; su&nbsp; predstavljeni najznačajniji vegetacijski tipovi ovog područja, date su&nbsp; fitocenolo&scaron;ke&nbsp; tabele&nbsp; snimaka&nbsp; koji&nbsp; su&nbsp; za&nbsp; ove zajednice&nbsp; uzeti&nbsp; u&nbsp; toku&nbsp; terenskog&nbsp; istraživanja, fotografije zajednica i mape sa tačkama na kojima su uzimani&nbsp; snimci.&nbsp; U&nbsp; okviru&nbsp; pregleda&nbsp; vegetacije Deliblatske pe&scaron;čare, pored već poznatih vegetacijskih jedinica,&nbsp; po&nbsp; prvi&nbsp; put&nbsp; su&nbsp; predstavljene&nbsp; tri&nbsp; asocijacije autohtone&nbsp; vegetacije&nbsp; i&nbsp; dve&nbsp; sastojine&nbsp; antropogenih zajednica.&nbsp; U&nbsp; cilju&nbsp; razre&scaron;avanja&nbsp; problematike klasifikacije&nbsp; pe&scaron;čarske&nbsp; vegetacije,&nbsp; prikupljeni&nbsp; su&nbsp; i<br />analizirani fitocenolo&scaron;ki podaci za čitavu Srbiju, ali i ceo&nbsp; Panonski&nbsp; i&nbsp; Pontski&nbsp; basen.&nbsp; Na&nbsp; ovaj&nbsp; način&nbsp; je detaljno&nbsp; razja&scaron;njena&nbsp; klasifikacija&nbsp; psamofitskih zajednica&nbsp; Deliblatske&nbsp; pe&scaron;čare&nbsp; do&nbsp; nivoa subasocijacija. Dinamika&nbsp; vegetacije&nbsp; Deliblatske&nbsp; pe&scaron;čare&nbsp; je analizirana&nbsp; praćenjem&nbsp; sukcesivnih&nbsp; stadijuma obrastanja&nbsp; peska&nbsp; i&nbsp; zatvaranjem&nbsp; sklopa&nbsp; sastojina. Monitoring je podrazumevao i pedolo&scaron;ke analize na<br />na&nbsp; lokalitetima&nbsp; različitih&nbsp; vegetacijskih&nbsp; tipova.&nbsp; U okviru&nbsp; praćenja&nbsp; dinamike&nbsp; vegetacije,&nbsp; realizovana&nbsp; su istraživanja&nbsp; na&nbsp; područjima&nbsp; na&nbsp; kojima&nbsp; se&nbsp; vr&scaron;i revitalizacija stepskih sastojina. Rezultati ukazuju da je&nbsp; su&nbsp; revitalizacijom&nbsp; postignuti&nbsp; dobri&nbsp; rezultati&nbsp; koje treba&nbsp; dalje&nbsp; usmeravati&nbsp; i&nbsp; korigovati&nbsp; u&nbsp; pravcu postizanja&nbsp; optimalnih&nbsp; uslova&nbsp; za&nbsp; opstanak&nbsp; i&nbsp; razvoj stepske, ali i drugih tipova vegetacije.<br />Rezultati&nbsp; ove&nbsp; doktorske&nbsp; disertacije&nbsp; daju&nbsp; dobru osnovu za dalja floristička i vegetacijska istraživanja Deliblatske&nbsp; pe&scaron;čare,&nbsp; ali&nbsp; i&nbsp; drugih,&nbsp; sličnih,&nbsp; prirodnih<br />područja&nbsp; i&nbsp; značajan&nbsp; doprinos&nbsp; proučavanju&nbsp; flore&nbsp; i vegetacije Srbije.</p> / <p>In this research was analyzed flora and vegetation of the&nbsp; Deliblato&nbsp; Sands.&nbsp; The&nbsp; aim&nbsp; of&nbsp; the&nbsp; study&nbsp; was&nbsp; to determine the recent state and basic characteristics of the flora of Deliblato Sands, as well as to analyze the dynamics&nbsp; of&nbsp; flora&nbsp; in&nbsp; the&nbsp; last&nbsp; 220&nbsp; years.&nbsp; One&nbsp; of&nbsp; the aims&nbsp; was&nbsp; to&nbsp; analyze&nbsp; the&nbsp; successive&nbsp; changes&nbsp; in&nbsp; the flora&nbsp; and&nbsp; vegetation&nbsp; of&nbsp; Deliblato&nbsp; Sands&nbsp; and&nbsp; the prediction of their direction and&nbsp; quality. Also, one of the&nbsp; goals&nbsp; was&nbsp; to&nbsp; determine&nbsp; the&nbsp; diversity&nbsp; and syntaxonomical&nbsp; scheme&nbsp; of&nbsp; vegetation&nbsp; through classification&nbsp; of problematic vegetation groups in the wider&nbsp; aspect&nbsp; -&nbsp; at&nbsp; the&nbsp; level&nbsp; of&nbsp; the&nbsp; whole&nbsp; Serbia,&nbsp; but also of Pontic and Pannonian region. Field&nbsp; research were&nbsp; carried&nbsp; out&nbsp; in&nbsp; the&nbsp; period&nbsp; 2012-2018.&nbsp; Floristic data were taken at the same sites as phytocenological plots.&nbsp; In&nbsp; total,&nbsp; 282&nbsp; phytosociological&nbsp; relev&eacute;s&nbsp; were taken&nbsp; using&nbsp; the&nbsp; Braun-Blanquet&nbsp; method.&nbsp; 301 different&nbsp; references&nbsp; were&nbsp; processed&nbsp; for&nbsp; floristic analysis&nbsp; and&nbsp; data&nbsp; for&nbsp; 440&nbsp;&nbsp; species&nbsp; were&nbsp; collected&nbsp; in the field&nbsp; (6 of them&nbsp; were registered for the first time in&nbsp; this&nbsp; area).&nbsp; A&nbsp; total&nbsp; of&nbsp; 9,887&nbsp; data&nbsp; collected&nbsp; were included in the floristic analysis. The&nbsp; research&nbsp; gives a&nbsp; floristic&nbsp; overview&nbsp; in&nbsp; the&nbsp; form&nbsp; of&nbsp; a&nbsp; list&nbsp; of&nbsp; taxa recorded&nbsp; in&nbsp; Deliblato&nbsp; Sandst&nbsp; (there&nbsp; are&nbsp; 1072&nbsp; taxa), with the localities where they have been&nbsp; found so far, and&nbsp; the first findings for species and subspecies are marked, as well as the&nbsp; species confirmed in the field research&nbsp; within&nbsp; this&nbsp; dissertation.&nbsp; Floristic&nbsp; analysis was performed using classical numerical methods, in order&nbsp; to&nbsp; present&nbsp; the&nbsp; most&nbsp; represented&nbsp; families, genera,&nbsp; life&nbsp; forms&nbsp; and&nbsp; chorotypes.&nbsp; Endemic,&nbsp; relict and&nbsp; endangered&nbsp; and&nbsp; invasive&nbsp; species&nbsp; of&nbsp; Sandstone are&nbsp; presented.&nbsp; 16&nbsp; endemic,&nbsp; 22&nbsp; relicts,&nbsp; 49&nbsp; strictly protected, 8 from the Red Data Book of Serbian flora and 54 invasive taxa have been recorded in Deliblato Sands.&nbsp; The&nbsp; dynamics&nbsp; of&nbsp; floristic&nbsp; research&nbsp; is represented&nbsp; by&nbsp; the&nbsp; analysis&nbsp; of&nbsp; literary&nbsp; data&nbsp; and&nbsp; the dynamics&nbsp; of&nbsp; research&nbsp; activities&nbsp; in&nbsp; this&nbsp; area.&nbsp; In accordance with the significant social changes of the area,&nbsp; it&nbsp; is&nbsp; noted&nbsp; that&nbsp; the&nbsp; most&nbsp; significant&nbsp; event&nbsp; was the&nbsp; beginning&nbsp; of&nbsp; afforestation&nbsp; of&nbsp; the&nbsp; Sand.&nbsp; The vegetation&nbsp; overview&nbsp; of the Deliblato&nbsp; Sands presents the&nbsp; most&nbsp; significant&nbsp; vegetation&nbsp; types&nbsp; of&nbsp; the&nbsp; area, provides&nbsp; phytosociological&nbsp; tables&nbsp; of&nbsp; relev&eacute;s&nbsp; takenduring&nbsp; this&nbsp; research,&nbsp; photographs&nbsp; of&nbsp; communities and&nbsp; maps&nbsp; with&nbsp; points&nbsp; where&nbsp; the&nbsp; recordings&nbsp; were taken.&nbsp; In&nbsp; addition&nbsp; to&nbsp; the&nbsp; already&nbsp; known&nbsp; vegetation units,&nbsp; within&nbsp; the&nbsp; vegetation&nbsp; review&nbsp; of&nbsp; the&nbsp; Deliblat Sandstone,&nbsp; three&nbsp; associations&nbsp; of&nbsp; indigenous vegetation&nbsp; and&nbsp; two&nbsp; stands&nbsp; of&nbsp; anthropogenic communities&nbsp; were&nbsp; presented&nbsp; for&nbsp; the&nbsp; first&nbsp; time.&nbsp; In order to solve the problem of classification of sandy vegetation, phytocenological data were collected and analyzed for the whole Republic of Serbia, as well as the&nbsp; entire&nbsp; Pannonian&nbsp; and&nbsp; Pontic&nbsp; basin.&nbsp; In&nbsp; this&nbsp; way, the classification of the psammophytic&nbsp; communities of&nbsp; the&nbsp; Deliblato&nbsp; Sands&nbsp; to&nbsp; the&nbsp; level&nbsp; of&nbsp; subassociations was clarified. The vegetation dynamics of the Deliblato Sands were analyzed&nbsp; by&nbsp; monitoring&nbsp; successive&nbsp; stages&nbsp; of&nbsp; sand and&nbsp; steppe&nbsp; vegetation.&nbsp; Monitoring&nbsp; also&nbsp; included pedological&nbsp; analyzes&nbsp; at&nbsp; sites&nbsp; of&nbsp; different&nbsp; vegetation types.&nbsp; As&nbsp; part&nbsp; of&nbsp; the&nbsp; monitoring&nbsp; of&nbsp; vegetation dynamics,&nbsp; research&nbsp; has&nbsp; been&nbsp; carried&nbsp; out&nbsp; in&nbsp; areas where steppe stands are being revitalized. The results indicate&nbsp; that&nbsp; the&nbsp; revitalization&nbsp; has&nbsp; achieved&nbsp; good results that need to be further directed and corrected in&nbsp; order&nbsp; to&nbsp; achieve&nbsp; optimal&nbsp; conditions&nbsp; for&nbsp; the survival&nbsp; and&nbsp; development&nbsp; of&nbsp; steppe&nbsp; and&nbsp; other vegetation types. The&nbsp; results&nbsp; of&nbsp; this&nbsp; doctoral&nbsp; dissertation&nbsp; provide&nbsp; a good&nbsp; basis&nbsp; for&nbsp; further&nbsp; floristic&nbsp; and&nbsp; vegetation research&nbsp; in&nbsp; the&nbsp; Deliblato&nbsp; sands,&nbsp; as&nbsp; well&nbsp; as&nbsp; other similar natural areas and a significant contribution to the study of the flora and vegetation of Serbia.</p>
29

Mammoth Cave National Park : distribution and classification of woody vegetation

Shell, Melissa K. January 1995 (has links)
Mammoth Cave National Park (MCNP) contains a diversity of forest types due to a complex mosaic of landform, rock types and land-use history. The point-centered quarter method was used to collect data for a forested vegetation classification. Stratified random sampling was done in each of the various site types found within the boundaries of MCNP. A classification based on the information available in the matrix of species importance values from each site type was constructed using two-way indicator species analysis (TWINSPAN). Geographic Information System (GIS) analysis was used to devise an automated vegetation mapping model that can be used to predict vegetation from environmental variables. A tool to assess the accuracy of model predictions was devised. The predicted vegetation map was stored within the GIS, and allows access to a variety of data associated with inventored, classifed, and predicted plant community types. / Department of Biology
30

Hybrid image classification technique for land-cover mapping in the arctic tundra, North Slope, Alaska

Chaudhuri, Debasish. January 1900 (has links)
Dissertation (Ph.D.)--The University of North Carolina at Greensboro, 2008. / Title from PDF t.p. (viewed Aug. 10, 2009). Directed by Roy Stine; submitted to the Dept. of Geography. Includes bibliographical references (p. 154-165).

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