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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.
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Spatio-temporal analyses of woody vegetation cover using remote sensing techniques: the case of Alice - King Williams Town route, Eastern Cape, South AfricaFundisi, 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.
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A família Myrtaceae na Floresta Nacional de Ipanema, Iperó, São Paulo, Brasil / The family Myrtaceae at Nacional Forest of Ipanema, Iperó, São Paulo, BrasilSilva, Alan Teixeira da 10 June 2014 (has links)
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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.
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Vegetation description and mapping along a strip transect in central Namibia with the aid of satellite imageryStrohbach, 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
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The Feasibility of Using LANDSAT Thematic Mapper Data for Fine Scale Vegetation Classification in Southern OntarioHawes, 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
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A floristic study of a former land bridge in The Bahama ArchipelagoDaniels, Mark Leo 04 August 2016 (has links)
No description available.
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Classification of vegetation of the South African grassland biomeEllery, 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
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Status i vremenska dinamika flore i vegetacije Deliblatske peščare / Status and temporal dynamics of the flora and vegetation of the Deliblaot SandsĆuk Mirjana 27 September 2019 (has links)
<p>U radu je analizirana flora i vegetacija Deliblatske peščare. Cilj istraživanja bio je utvrđivanje recentnog stanja i osnovnih karakteristika flore Deliblatske peščare, ali i analiza dinamike flore Deliblatske peščare u poslednjih 220 godina. Jedan od ciljeva je bila analiza sukcesivnih promena u flori i vegetaciji Deliblatske peščare i predikcija njihovog pravca i kvaliteta, kao i utvrđivanje diverziteta i sintaksonomske šeme vegetacije Deliblatske peščare uz klasifikaciju problematičnih vegetacijskih grupa u širem aspektu- na nivou čitave Srbije, ali i Pontskog i Panonskog regiona. Terenska istraživanja su vršena u periodu 2012-2018 godine. Floristički podaci su uzimani na istim lokalitetima kao i fitocenološki snimci. Ukupno je uzeto 282 fitocenološka snimka metodom po Braun-Blankeu. Za florističku analizu je<br />obrađena 301 referenca, a na terenu su prikupljeni podaci za 440 vrsta, od kojih je 6 po prvi put registrovano na ovom području. U florističku analizu je uključeno ukupno prikupljenih 9.887 podataka. U radu je dat floristički pregled u vidu spiska taksona koji su zabeleženi na Deliblatskoj peščari (ima ih 1072), sa lokalitetima na kojima su do sada pronađeni, obeleženi su prvi nalazi za vrste i<br />podvrste, a obeležene su i vrste koje su potvrđene na terenskim istraživanjima u okviru ove disertacije. Floristička analiza je realizovana klasičnim numeričkim metodama, u cilju prezentacije najzastupljenijih familija, rodova, životnih formi i<br />horotipova. Predstavljene su endemične, reliktne i ugrožene i ivnazivne vrste Peščare. Na Deliblatskoj peščari je zabeleženo 16 endemskih, 22 reliktnih, 49 strogo zaštićenih, 8 iz Crvenje knjige flore Srbije i 54 invazivna taksona. Dinamika florističkih istraživanja je predstavljena analizom literaturnih podataka i dinamike istraživanja ovog područja, a u skladu sa značajnim društvenim promenama područja, od kojih se kao najznačajniji momenat izdvaja početak pošumljavanja Peščare. U pregledu vegetacije Deliblatske peščare su predstavljeni najznačajniji vegetacijski tipovi ovog područja, date su fitocenološke tabele snimaka koji su za ove zajednice uzeti u toku terenskog istraživanja, fotografije zajednica i mape sa tačkama na kojima su uzimani snimci. U okviru pregleda vegetacije Deliblatske peščare, pored već poznatih vegetacijskih jedinica, po prvi put su predstavljene tri asocijacije autohtone vegetacije i dve sastojine antropogenih zajednica. U cilju razrešavanja problematike klasifikacije peščarske vegetacije, prikupljeni su i<br />analizirani fitocenološki podaci za čitavu Srbiju, ali i ceo Panonski i Pontski basen. Na ovaj način je detaljno razjašnjena klasifikacija psamofitskih zajednica Deliblatske peščare do nivoa subasocijacija. Dinamika vegetacije Deliblatske peščare je analizirana praćenjem sukcesivnih stadijuma obrastanja peska i zatvaranjem sklopa sastojina. Monitoring je podrazumevao i pedološke analize na<br />na lokalitetima različitih vegetacijskih tipova. U okviru praćenja dinamike vegetacije, realizovana su istraživanja na područjima na kojima se vrši revitalizacija stepskih sastojina. Rezultati ukazuju da je su revitalizacijom postignuti dobri rezultati koje treba dalje usmeravati i korigovati u pravcu postizanja optimalnih uslova za opstanak i razvoj stepske, ali i drugih tipova vegetacije.<br />Rezultati ove doktorske disertacije daju dobru osnovu za dalja floristička i vegetacijska istraživanja Deliblatske peščare, ali i drugih, sličnih, prirodnih<br />područja i značajan doprinos proučavanju flore i vegetacije Srbije.</p> / <p>In this research was analyzed flora and vegetation of the Deliblato Sands. The aim of the study was to determine the recent state and basic characteristics of the flora of Deliblato Sands, as well as to analyze the dynamics of flora in the last 220 years. One of the aims was to analyze the successive changes in the flora and vegetation of Deliblato Sands and the prediction of their direction and quality. Also, one of the goals was to determine the diversity and syntaxonomical scheme of vegetation through classification of problematic vegetation groups in the wider aspect - at the level of the whole Serbia, but also of Pontic and Pannonian region. Field research were carried out in the period 2012-2018. Floristic data were taken at the same sites as phytocenological plots. In total, 282 phytosociological relevés were taken using the Braun-Blanquet method. 301 different references were processed for floristic analysis and data for 440 species were collected in the field (6 of them were registered for the first time in this area). A total of 9,887 data collected were included in the floristic analysis. The research gives a floristic overview in the form of a list of taxa recorded in Deliblato Sandst (there are 1072 taxa), with the localities where they have been found so far, and the first findings for species and subspecies are marked, as well as the species confirmed in the field research within this dissertation. Floristic analysis was performed using classical numerical methods, in order to present the most represented families, genera, life forms and chorotypes. Endemic, relict and endangered and invasive species of Sandstone are presented. 16 endemic, 22 relicts, 49 strictly protected, 8 from the Red Data Book of Serbian flora and 54 invasive taxa have been recorded in Deliblato Sands. The dynamics of floristic research is represented by the analysis of literary data and the dynamics of research activities in this area. In accordance with the significant social changes of the area, it is noted that the most significant event was the beginning of afforestation of the Sand. The vegetation overview of the Deliblato Sands presents the most significant vegetation types of the area, provides phytosociological tables of relevés takenduring this research, photographs of communities and maps with points where the recordings were taken. In addition to the already known vegetation units, within the vegetation review of the Deliblat Sandstone, three associations of indigenous vegetation and two stands of anthropogenic communities were presented for the first time. 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 entire Pannonian and Pontic basin. In this way, the classification of the psammophytic communities of the Deliblato Sands to the level of subassociations was clarified. The vegetation dynamics of the Deliblato Sands were analyzed by monitoring successive stages of sand and steppe vegetation. Monitoring also included pedological analyzes at sites of different vegetation types. As part of the monitoring of vegetation dynamics, research has been carried out in areas where steppe stands are being revitalized. The results indicate that the revitalization has achieved good results that need to be further directed and corrected in order to achieve optimal conditions for the survival and development of steppe and other vegetation types. The results of this doctoral dissertation provide a good basis for further floristic and vegetation research in the Deliblato sands, as well as other similar natural areas and a significant contribution to the study of the flora and vegetation of Serbia.</p>
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Mammoth Cave National Park : distribution and classification of woody vegetationShell, 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
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Hybrid image classification technique for land-cover mapping in the arctic tundra, North Slope, AlaskaChaudhuri, 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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