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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.
1

Spatial characterization of vegetation diversity with satellite remote sensing in the khakea-bray transboundary aquifer

Mpakairi, Kudzai Shaun January 2022 (has links)
>Magister Scientiae - MSc / There have been increasing calls to monitor Groundwater-Dependent Ecosystems (GDEs) more effectively, since they are biodiversity hotspots that provide several ecosystem services. The accurate monitoring of GDEs is an indispensable under Sustainable Development Goal (SDG) 15, because it promotes the existence of phreatophytes. It is imperative to monitoring GDEs, since their ecological significance (e.g., as biodiversity hotspots) is not well understood in most environments they exist. For example, vegetation diversity in GDEs requires routine monitoring, to conserve their biodiversity status and to preserve the ecosystem services in these environments. Such monitoring requires robust measures and techniques, particularly in arid environments threatened by groundwater over–abstraction, landcover and climate change. Although in–situ methods are reliable, they are challenging to use in extensive transboundary groundwater resources such as the Khakea-Bray Transboundary Aquifer.
2

Microtopographic enhancement of land-based wastewater treatment

Tyrrell, Sean R. January 2016 (has links)
There is a regulatory tension within wastewater treatment, between the requirement to meet tightening consents and the need to reduce the carbon footprint of treatment processes. With 75% of wastewater treatment works serving populations of less than 2,000, low-energy tertiary treatment options suitable to small rural works need to be developed. One option that lends itself particularly well to small works is land-based wastewater treatment (LBWWT). The aim of this research was to evaluate the role of LBWWT in the UK water industry and investigate the impact ridge-and-furrow enhanced microtopography (MT) may have upon a particular type of LBWWT - slow-rate (SR) infiltration. This was achieved through meeting three objectives. Firstly, the use of LBWWT was reviewed and assessed. Secondly, the impact of ridge-and-furrow enhanced MT upon the vegetation diversity and nutrient removal of a SR- LBWWT was established by means of a three year field trial. Finally, the cost- effectiveness of SR-LBWWT and the impact of ridging and furrow irrigation upon cost-effectiveness were evaluated using Cost-Effectiveness Analysis (CEA). The first objective comprised of a review of the historical and current use of LBWWT, a review of the relevant changing legislation to identify what may be required of LBWWT and an assessment of LBWWT’s potential to meet these requirements. The result of the evaluation found that, based upon the literature, SR-LBWWT is ‘fit-for-purpose’ as tertiary treatment for small treatment works. To meet the second objective, a SR-LBWWT system trial was established at a small wastewater treatment works in Knowle, Hampshire. The trial consisted of three clay-loam grass plots irrigated with secondary treated effluent. There were two configurations of trial plot - flat and ridge-and-furrowed. Effluent (sub- surface soil water) nutrient concentrations were monitored as was vegetation diversity. In addition a number of physical, hydrological and biogeochemical parameters were monitored and hydrological modelling carried out. Mean nutrient removal performances of 90% for ammonia, 72% for nitrate, and 91% for phosphate were observed with the ridge-and-furrowed plot. Ridging and furrow irrigation was found to not have a significantly detrimental effect upon the trial plots’ removal performance for ammonia, nitrate or phosphate. Extrapolation modelling suggested, however, that this would not be the case for LBWWT systems on predominantly clay or sand soils. Ridging and furrow irrigation was found to have a statistically significant positive effect upon the vegetation diversity of the LBWWT trial plots; with mean final year Shannon-Wiener values of 0.96 and 0.69, for the ridge-and-furrowed and non-ridged plots, respectively. For the final objective, analysis found that SR-LBWWT are cost-effective when compared to horizontal sub-surface flow constructed wetlands (HSSFCW), an established low-energy treatment option. Mean cost-effectiveness ratio values of £208.5 and £262.7 per % effectiveness were observed for LBWWT and HSSFCW, respectively. Following the field trial CEA was extended to include ridge-and-furrowed SR-LBWWT systems. This found that ridging and furrow irrigation improves the cost-effectiveness of SR-LBWWT serving small populations, reducing the mid cost-effectiveness ratio to £193 per % effectiveness. This is a result of the cost-reducing effect of ridge-and-furrowing over laser-level grading; and based upon the findings of the trial that ridging and furrow irrigation can be achieved (in clay-loam soil slow-rate systems) without significant detriment to the water treatment effectiveness of LBWWT. The main conclusions of this thesis are: that SR-LBWWT has a role to play in the UK water industry, as tertiary treatment for small wastewater treatment works. That SR-LBWWT is cost-effective in relation to HSSFCW. That ridging and furrow irrigation increases that cost-effectiveness by reducing the construction and operational costs. That ridging and furrow irrigation can be employed without significant detriment to a SR-LBWWT system’s water treatment performance. And finally, that ridging and furrow irrigation can have a positive impact upon the establishment vegetation diversity of a SR-LBWWT system.
3

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>
4

Diverzita lesní vegetace Českého středohoří / Diversity of forest vegetation in the region of České středohoří

Tydlitátová, Klára January 2010 (has links)
Abstract The topography of the Milešov part of the České středohoří Mts represents a suitable model for study of spatial distribution of diversity and the effects of ecological factors on species diversity and composition. Near-natural forest vegetation was sampled at eleven hills by stratified-randomly sited relevés. Soil samples were collected in relevés at nine hills also. The soil samples were used for maximal capillary capability, pH, carbon and nitrogen volume analyses. These ecological factors, as well as tree cover, altitude and heat load index, were used for examination of the correlation of ecological factors with diversity, species richness and species composition. Positive relationship between species richness and heat load index and soil reaction was identified. Species diversity (Shannon index) positively correlates with soil reaction also. After partialling out geographic components in the samples, a significant correlation between the heat load index, tree cover and altitude and species composition of the herb and shrub layer was found. Values of alpha and beta components were rated using partitioning of diversity to alpha and beta components at four levels (relevé - aspect - hill - landscape). The beta component at the aspect level and the beta component at the hill level were...
5

Modeling of vegetation diversity and a national conservation planning: example of Russia / Modeling of vegetation diversity and a national conservation planning: example of Russia

Venevskaia, Irina January 2004 (has links)
Die übergreifende Zielsetzung meiner Studie ist eine Ausarbeitung quantitativer Methoden zur nationalen nationale Schutzplanung in Übereinstimmung mit dem internationalen Ansatz. Diese Zielsetzung erfordert eine Lösung der folgenden Probleme:<br><br> 1) Wie lässt sich Vegetationsvielfalt in grober Auflösung auf Basis abiotischen Faktoren einschätzen?<br> 2) Wie ist der Ansatz 'globaler Hotspots' für die Eingrenzung nationaler Biodiversitäts-Hotspots zu übernehmen?<br> 3) Wie erfolgt die Auswahl von quantitativen Schutzzielen unter Einbezug der Unterschiede nationaler Hotspots bei Umweltbedingungen und durch den Menschen Bedrohung?<br> 4) Wie sieht der Entwurf eines großflächigen nationalen Naturschutzkonzepts aus, das die hierarchische Natur der Artenvielfalt reflektiert? Die Fallstudie für nationale Naturschutzplanung ist Russland. <br><br> Die nachfolgenden theoretischen Schlüsse wurden gezogen:<br> · Großräumige Vegetationsdiversität ist weitgehend vorhersagbar durch klimabedingte latente Wärme für Verdunstung und topographische Landschaftsstruktur, beschrieben als Höhendifferenz. Das klimabasierte Modell reproduziert die beobachtete Artenanzahl von Gefäßpflanzen für verschiedene Gebiete auf der Welt mit einem durchschnittlichen Fehler von 15% <br> · Nationale Biodiversitäts-Hotspots können auf Grundlage biotischer oder abiotischer Daten kartographiert werden, indem als Korrektur für ein Land die quantitativen Kriterien für Planzenendemismus und Landnutzung des Ansatzes der 'globalen Hotspots' genutzt wird <br> · Quantitative Naturschutzziele, die die Unterschiede zwischen nationalen Biodiversitäts-Hotspots in Bezug auf Umweltbedingungen und der Bedrohung durch den Menschen miteinbeziehen, können mit nationalen Daten über Arten auf der Roten Liste gesetzt werden <br> · Ein großräumiger nationaler Naturschutzplan, der die hierarchische Natur der Artenvielfalt berücksichtigt, kann durch eine Kombination von abiotischer Methode im nationalen Bereich (Identifikation großräumiger Hotspots) und biotischer Methode im regionalen Bereich (Datenanalyse der Arten auf der Roten Liste) entworfen werden / The overall objective of the study is an elaboration of quantitative methods for national conservation planning, coincident with the international approach ('hotspots' approach). This objective requires a solution of following problems: <br><br> 1) How to estimate large scale vegetation diversity from abiotic factors only?<br> 2) How to adopt 'global hotspots' approach for bordering of national biodiversity hotspots?<br> 3) How to set conservation targets, accounting for difference in environmental conditions and human threats between national biodiversity hotspots?<br> 4) How to design large scale national conservation plan reflecting hierarchical nature of biodiversity?<br> The case study for national conservation planning is Russia. <br><br> Conclusions:<br> · Large scale vegetation diversity can be predicted to a major extent by climatically determined latent heat for evaporation and geometrical structure of landscape, described as an altitudinal difference. The climate based model reproduces observed species number of vascular plant for different areas of the world with an average error 15%<br> · National biodiversity hotspots can be mapped from biotic or abiotic data using corrected for a country the quantitative criteria for plant endemism and land use from the 'global hotspots' approach<br> · Quantitative conservation targets, accounting for difference in environmental conditions and human threats between national biodiversity hotspots can be set using national data for Red Data book species <br> · Large scale national conservation plan reflecting hierarchical nature of biodiversity can be designed by combination of abiotic method at national scale (identification of large scale hotspots) and biotic method at regional scale (analysis of species data from Red Data book)
6

Soil Genesis and Vegetation Response to Amendments and Microtopography in Two Virginia Coastal Plain Created Wetlands

Ott, Emily Thomas 12 June 2018 (has links)
Wetlands serve important ecosystem functions such as carbon sequestration but are often affected by disturbances like urban development, agriculture, and road building. For wetlands created to mitigate losses, it is important that the ecosystem functions successfully replicate those of natural wetlands. Created wetlands have frequently not provided these functions due to issues including low organic carbon (OC), high soil bulk density (BD), lost topsoil, incorrect hydrology, and failure of targeted vegetation establishment. Organic matter (OM) amendments help created wetlands attain these functions quicker, but, their long-term effects are seldom reported. This research's purpose was to measure the long-term effects of treatments at a sandy tidal freshwater wetland created in 2003 (WWE) and a fine-textured, non-tidal wetland created in 2002 (CCW). We tested OM treatments, topsoil amendment, and microtopography effects on soil and vegetation properties at WWE and OM treatments at CCW. Pedogenic changes in soil morphology, physical and chemical properties were detected by comparing data to previous studies at these sites. At both sites, litter and biomass parameters were measured to estimate total mass C. Herbaceous biomass was measured at WWE. At WWE, no long-term OM treatment effects from 78 or 156 Mg ha-1 were observed. Soils in pits had higher OC, lower BD, and lower chroma than soils on mounds. Sandy and loamy HSFI's developed at WWE within four years, but there were fewer sandy indicators after 12 years. Loamy HSFI's were lost at CCW from 2003 to 2016. Plots at WWE that were amended with topsoil had higher soil mass C than the sandy soil due to a finer texture, but total mass C did not vary. At CCW, long-term OM treatment effects were observed, including lower BD, higher soil mass C, and higher tree mass C with increasing compost rates up to 224 Mg ha-1. Overall, the ideal compost loading rate for constructed wetlands varied with wetland type and mitigation goals. Compost rates of 112 Mg ha-1 are sufficient for short term establishment of wetland vegetation and hydric soil properties, but higher rates near 224 Mg ha-1 may be required for effects that last over 10 years. / Ph. D.
7

Population dynamics of hybrid ecosystems: Implications for marginal ecosystem conservation and management

Nichter, Ashlee N. 29 November 2017 (has links)
No description available.

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