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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.
271

Historical inventory of sedimentary carbon and metals in a Bay of Fundy salt marsh

Clegg, Yolanda. January 1999 (has links)
In 1996, four cores (∼30 cm depth) were extracted from the high marsh zone of Dipper Harbour salt marsh in the Bay of Fundy. Soil bulk densities are shown to be controlled by mineral density and are higher than those reported for salt marshes in the northeastern United States. Examination of variations in mineral content suggests that regular tidal action and ice rafting deposits the majority of the mineral sediment to the high marsh zone. Dating techniques (based upon pollen, 137Cs, 210Pb and total Pb) were applied to selected cores, suggesting accretion rates from 0.25 to 0.31 cm yr-1 which are higher than the rates of local relative sea level rise. Correlation of trace metal densities (Cu, Fe, Pb and Zn) to Al densities were used to justify Al normalization. After consideration of natural sources and adsorption factors, the normalized Pb profiles are shown to reflect historical pollution levels of leaded gasoline consumption. Carbon storage values in the upper 25 cm of sediment range from 7.3--10.5 kg C m-2 and carbon accumulation rates vary from 95 to 124 g C m-2 yr-1, representing 15--29% of the salt marsh macrophyte productivity.
272

Impact of a carbon market on afforestation incentives : a real option approach

Jetté-Nantel, Simon. January 2006 (has links)
The study investigates farmers' decision to afforest marginal agricultural land to create carbon sinks in western Canada. A real option model, which incorporates price risks related to carbon and timber revenues as well as opportunity cost uncertainty, is used to assess the impact of a carbon market on farmers' afforestation decision. Irreversibility of the decision is also modeled by including sunk cost of forest establishment and the cost of reversing the afforestation process. In addition, the non-permanence impact on the profitability of afforestation was analyzed by assessing the effect of two non-permanence carbon accounting schemes. / Results indicate that both, actual non-permanence policies and the presence of real options, have a significant negative impact on afforestation incentives. However, the carbon market has a positive effect as it increases the expected revenues to afforestation and also represents a diversification opportunity. Yet, even in the presence of a carbon market the investment barrier remains considerable. Despite the positive effect of the carbon market, results show that unless carbon prices reach levels well above $100/tC a subsidization of afforestation cost is needed in order to generate substantial GHG abatement from marginal agricultural land afforestation in western Canada.
273

Tree growth and mortality and implications for restoration and carbon sequestration in Australian subtropical semi-arid forests and woodlands

John Dwyer Unknown Date (has links)
Many researchers have highlighted the dire prospects for biodiversity in fragmented agricultural landscapes and stressed the need for increasing the area of, and connectivity between, natural ecosystems. Some have advocated the use of naturally regenerating forest ecosystems for sequestering atmospheric carbon, with opportunities for dual restoration and carbon benefits. However, no studies have explicitly explored the feasibility of obtaining such dual benefits from a regenerating woody ecosystem. This thesis aims to provide a detailed assessment of the restoration and carbon potential of Brigalow regrowth, an extensive naturally regenerating ecosystem throughout the pastoral regions of north eastern Australia. It combines observational, experimental and modelling techniques to describe the agricultural legacy of pastoral development, identify constraints to restoration and explore methods to remove these constraints. A review of existing ecological knowledge of Brigalow ecosystems is provided in chapter 3, along with discussion of policy and socio-economic issues that are likely to influence how and to what extent regrowth is utilised for restoration and carbon purposes in the Brigalow Belt. The review found restoring regrowth is likely to have benefits for a wide range of native flora and fauna, including the endangered bridled nailtail wallaby. Knowledge gaps exist relating to the landscape ecology of Brigalow regrowth and the impacts of management and climate change on carbon and restoration potential. Also, a conflict exists between short-term carbon sequestration and long-term restoration goals. Regional demand for high biomass regrowth as a carbon offset is likely to be high but ambiguities in carbon policy threaten to diminish the use of natural regrowth for reforestation projects. A large cross-sectional study of regrowth is presented in chapter 4. Data were analysed using multi-level / hierarchical Bayesian models (HBMs). Firstly, we found that repeated attempts at clearing Brigalow regrowth increases stem densities and densities remain high over the long term, particularly in high rainfall areas and on clay soils with deep gilgais. Secondly, higher density stands have slower biomass accumulation and structural development in the long term. Spatial extrapolations of the HBMs indicated that the central and eastern parts of the study region are most environmentally suitability for biomass accumulation, however these may not correspond to the areas that historically supported the highest biomass Brigalow forests. We conclude that carbon and restoration goals are largely congruent within regions of similar climate. At the regional scale however, spatial prioritisation of restoration and carbon projects may only be aligned in areas with higher carbon potential. Given the importance of stem density in determining restoration and carbon potential, an experimental thinning trial was established in dense Brigalow regrowth in southern Queensland (chapter 5). Four treatments were applied in a randomised block design and growth and mortality of a subset of stems was monitored for two years. Data were analysed using mixed-effects models and HBMs and the latter were subsequently used to parameterise an individual-based simulation model of stand structural development and biomass accumulation over 50 years. The main findings of this study were that growth and mortality of stems is influenced by the amount of space available to each stem (a neighbourhood effect) and that thinning accelerates structural development and increases woody species diversity. The examination of neighbourhood effects is taken further by considering drought-related mortality in a Eucalyptus savanna ecosystem (chapter 6). For this work a multi-faceted approach was employed including spatial pattern analyses and statistical models of stem survival to test three competing hypotheses relating to neighbourhood effects on drought related tree mortality. The main finding of this study was that neighbour density and microsite effects both influence drought-related mortality and the observed patterns can readily be explained by an interaction between these two factors. As a whole, this thesis contributes the following scientific insights: (1) restoration and carbon goals may be aligned for naturally regenerating woody ecosystems, but the degree of goal congruence will vary across the landscape in question, (2) while some woody ecosystems retain an excellent capacity to regenerate naturally, the agricultural legacy may still have long term effects on restoration and carbon potential, (3) neighbourhood effects that operate at the stem scale strongly influence dynamics at the ecosystem scale.
274

Using algae to capture CO₂ and as a feedstock for biofuel

Archbold, Brad. January 2007 (has links) (PDF)
Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen (viewed 1/24/2008). Includes bibliographical references.
275

The liability of carbon dioxide storage /

De Figueiredo, Mark A. January 1900 (has links) (PDF)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2007. / Title from document title page. Includes bibliographical references. Available in PDF format via the World Wide Web.
276

Evaluation of carbon accounting models for plantation forestry in South Africa

Ndalowa, Dan 04 1900 (has links)
Thesis (MScFor)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The role that forestry plays in climate change mitigation is well recognized by countries that ratified the Kyoto protocol agreement. Though climate change mitigation strategies provide a strong incentive to quantify current patterns of forest carbon sources and sinks, this exercise (carbon accounting) is not as simple as it sounds. This is proven by the vast number of techniques and methodologies available, from models to softwares programmes created in response to the need to estimate carbon sequestration. The study aimed at gaining an understanding of the current carbon sequestration estimation methodology and models in use by the South African Forestry Industry. A survey was undertaken amongst forestry industry stakeholders in which 77% of respondents agreed to the need for a carbon sequestration model for South Africa. This model should have qualities that the forestry industry and all stakeholders agreed with. . A search of freely available models and software was conducted. The aim was to find freely available model(s) that would be readily applicable and adoptable to South African conditions. A Multi Criteria Analysis was carried out using “ideal qualities” for a carbon model as weighting. This resulted in the selection of two models, CASMOFOR and CBM CFS 3, which obtained the highest sum product total from the analysis. These together with FICAT, which came as a recommendation from the questionnaire survey, were compared in the analysis. Carbon values were calculated from yield table volumes by Kotze et al. (2012). A conversion of these volumes to biomass and carbon was done using Dovey (2009) biomass expansion factors and a biomass to carbon conversion value of 0.5 g C/g dry matter, following procedures by Matthews (1993). The first comparison was made on how the model results related to the yield table estimates from Kotze et al. (2012). When carbon values were compared per hectare, it was found that the FICAT model differed significantly from the rest. A second comparison looked at the models’ prediction of the carbon accumulated in NCT’s Enon plantation outside Pietermaritzburg. The Hungarian model, CASMOFOR, was the better predictor as it produced the lowest Mean Squared Error (MSE). Based on the results from the survey and model analysis a number of recommendations can be made regarding the current carbon accounting situation in South Africa. One of the main recommendations is that information sharing among the industry’s stakeholders should improve if the industry is to reach consensus on which methodology to adopt in their business practices. / AFRIKAANSE OPSOMMING: Die rol wat bosbou speel in klimaatsverandering-bekamping is welbekend onder lande wat die Kyoto protokol ooreenkoms onderteken het. Alhoewel klimaatsverandering-bekamping strategieë ‘n sterk aansporing bied om huidige patrone van woudkoolstof bronne en sinkte te kwantifiseer, is hierdie oefening nie so maklik soos dit klink nie. Die bewys hiervan is die groot aantal tegnieke en metodes, wat wissel van modelle tot sagteware programme wat ontwikkel is om koolstofsekwistrasie te meet. Die doelwit van die studie was om die huidige koolstofsekwistrasie metodes en modelle wat deur die Suid Afrikaanse Bosbou Bedryf gebruik word, beter te verstaan. ‘n Vraelysopname is onderneem onder bosbou-industrie deelnemers, waarin 77% van respondente saamgestem het dat dit nodig is dat Suid Afrika ‘n koolstofsekwistrasie model moet hê. Die model moet eienskappe hê waarmee die bosbou-industrie en alle deelnemers saamstem. ‘n Soektog na vrylik beskikbare koolstofmodelle en sagteware programme is onderneem. Die doelwit was om modelle te vind wat geredelik aangepas kan word vir Suid Afrikaanse toestande. ‘n Multi-kriteria analise is uitgevoer met die “ideale eienskappe”vir ‘n koolstofmodel as gewigte. Die resultaat was die seleksie van twee modelle, CASMOFOR en CBM CFS 3, wat die hoogste telling in die ontleding behaal het. Hierdie modelle, tesame met FICAT, wat aanbeveel is deur respondente van die vraelys opname, is vergelyk in ‘n ontleding. Koolstofwaardes is bereken vanaf opbrengstabelle wat deur Kotze et al. (2012) ontwikkel is. Die omsetting van hierdie volumes na biomassa en koolstof is gedoen deur Dovey (2009) se biomassa uitbreidingsfaktore en ‘n biomassa na koolstof omsettings faktor van 0.5 g C/g droëmassa te gebruik (Matthews, 1993). In die eerste vergelyking van die modelle is gekyk hoe die modelle vergelyk met koolstof berekeninge vanaf die Kotze et al. (2012) opbrengstabelle. Wanneer koolstofwaardes per hektaar vergelyk word is gevind dat FICAT beduidend verskil van die ander modelle. In ‘n tweede vergelyking is gekyk na hoe die modelle die koolstof wat in NCT se Enon plantasie buite Pietermaritzburg versamel is, voorspel. Die Hongaarse CASMOFOR model was die beste voorspeller. Anders as die FICAT en CBM CFS 3 modelle het dit die laagste Gemiddelde Vierkante Fout gehad. Na gelang van die resultate van die vraelysopname en die modelontleding kan ‘n aantal aanbevelings gemaak word oor die huidige koolstofberekening situasie in Suid Afrika. Een van die hoof aanbevelings is dat die uitruil van inligting tussen industrie deelnemers moet verbeter as die bedryf eenstemmigheid oor die metode van koolstofberekening wil bereik.
277

Carbon sequestration and trading potential in semi-arid South Africa : a Karoo case study

Paviour, Sarah-Jane 12 1900 (has links)
Thesis (MA)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The succulent thicket plant community of South Africa, particularly Portulacaria afra (in this study referred to as spekboom), occurring in the Thicket Biome, sequestrates an exceptional amount of carbon dioxide (due to its photosynthetic properties), particularly for a warm, semi-arid region and in this capacity is more akin to forest ecosystems. Spekboom has additional favourable characteristics over forested systems regarding carbon trading (CT), namely: economic water use; potential for combating desertification and poverty in arid environments; and ability to withstand stand-replacing fire (spekboom doesn’t burn) which improves its attraction as a commodity in CT and the payments for ecosystem services (PES) industry. Landowners interested in using the capacity of their land for carbon sequestration (CS) are challenged to calculate their plant communities’ sequestration ability and biodiversity potential and therefore to quantify the carbon credits to be sold. The aim of the study was to quantify the CS ability of a selected property unit by vegetation area and to establish the carbon credits value that can be sold in the carbon market. It commenced by highlighting the problem of global warming and its effect on climate change in South Africa. CS is described as a process and a solution to decrease high and rising atmospheric CO2 levels, and its use in the carbon market to attain a monetary value to promote the growing of vegetation or to protect and conserve biodiversity that will enhance carbon stocks. The study site is Bosch Luys Kloof Private Nature Reserve (BLK PNR) in the semi-arid Karoo. Because CS potential is known to follow a rainfall gradient, one expects the semi-arid Karoo to have a low CS potential. However, this area contains spekboom, an extraordinary thicket type that sequestrates carbon at similar rates to forest ecosystems and should therefore reap the benefits of CT. Yet, accurate mapping of this vegetation is critical for accurate carbon stocks assessment. The CS potential of all vegetation communities in the study area had to be established to estimate the carbon stocks in the whole property unit. ArcGIS was used to map the vegetation communities (sub biomes) and eCognition to refine mapping of the Gamka Thicket (containing spekboom) through an object-orientated approach to automated vegetation mapping. For accuracy assessment a heads-up digitized map was created for comparison. The true surface area was calculated for the vegetation classification to ensure accurate area accounting on the mountainous terrain and this calculated area of the mapped vegetation was used to convert area to carbon sequestration potential. By examining the different markets and trading mechanisms for trading in the carbon market, using CS, a marketing strategy for the land units was advised. Results show that due to BLK PNR's history of overstocking, spekboom remains degraded on the study site. This creates an opportunity to restore the vegetation with funding through CT. The sequestration potential of spekboom on BLK PNR was determined through a regional differentiation comparison. The regional differentiation comparison identified that rainfall amount and carbon accumulation are inversely proportional, therefore more arid conditions (<200mm a year, or a dry season longer than seven and a half months) cause spekboom to switch to Crassulacean acid metabolism (CAM) due to water stress, so increasing the rate of carbon accumulation. In wetter environments, where spekboom is not under water stress, it continues in carbon fixation of 3-phosphoglycerate (C3) having a lower carbon accumulation. This is a remarkable finding as CS is known to follow a rainfall gradient: in this instance spekboom is an exception to the norm. Mapped results showed that eCognition classified spekboom poorly, yielding between 64% and 69% correspondence to the accurate manually classified map. As expected three-dimensional area comparative results show that the true surface area on complex terrains was 10% higher than the original (and surveyed) land area of the estate. Results indicate that there are substantial carbon stocks for CT on BLK PNR. This study recommended the most practised form of CT (restoration) for BLK PNR. Over a period of 30 years of restoration on BLK PNR about 46 000 tons of carbon could be sequestrated. At the current price of carbon credits this could accumulate over R3.7 million over the 30-year restoration period. Combining restoration with conservation strategies into one project type has additional favourable characteristics as it takes into account the CS potential of all vegetation communities on the land unit and the ecosystem services it promotes. Conservation of BLK PNR would yield 758 000 tons of carbon. Calculated through emission abandonment, this could be valued at R8-10 million. The economic importance of the vegetation community’s biodiversity on BLK PNR and significant differences between biomes were recorded and implies a total intrinsic value in excess of R830 000 per annum. To date, pilot projects elsewhere have successfully acquired carbon credits for avoided deforestation through the climate, community and biodiversity alliance (CCBA). However, owing to the pilot stage status there is little literature that substantiates the calculation of the monetary value of conservation. This is a fertile area for further research. / AFRIKAANSE OPSOMMING: Die sukkulent-struikplantgemeenskap van Suid-Afrika, in besonder Portulacaria afra (waarna in hierdie studie as Spekboom verwys word), wat in die Struikgewasbioom voorkom, neem ‘n uitsonderlike hoeveelheid koolstofdioksied op (weens die fotosintetiese eienskappe daarvan), veral vir ‘n warm, semi-ariede streek en is in hierdie kapasiteit meer verwant aan woud-ekosisteme. Spekboom het, met betrekking tot koolstofuitruiling (KU) of koolstofhandel, addisionele gunstige eienskappe bo dié van woudsisteme, naamlik lae waterbenutting; potensiaal vir die bestryding van woestynvorming en armoede in ariede omgewings; en die vermoë om brand te weerstaan (Spekboom brand nie), wat sy aantreklikheid as ‘n kommoditeit in KU verhoog, en die betaling vir dienste in die ekosisteem-industrie (BED) verbeter. Grondeienaars wat geïnteresseerd is in die benutting van hul grond vir koolstofopname (KO), word uitgedaag om hul plantgemeenskappe se opnamevermoë en potensiaal vir biodiversiteit te bereken, en gevolglik die hoeveelheid koolstofkrediete wat verkoop kan word, te kwantifiseer. Die doel van die studie was om die KO-vermoë van ‘n geselekteerde eiendomseenheid volgens die oppervlakte onder plantegroei te kwantifiseer en om die waarde van koolstofkrediete wat in die koolstofmark verkoop kan word, vas te stel. Ten aanvang is die probleem van aardverwarming en die uitwerking daarvan op klimaatsverandering in Suid-Afrika uitgelig. KO word beskryf as ‘n proses en oplossing om die hoë en stygende atmosferiese CO2-vlakke te verminder, en die gebruik daarvan in die koolstofmark, om ‘n monetêre waarde te verkry om plantbedekking te bevorder of om biodiversiteit, wat koolstofvoorraad sal vermeerder, te beskerm en te bewaar. Die studieperseel is Bosch Luys Kloof Privaat Natuurreservaat (BLK PNR) in die semi-ariede Karoo. Omrede KO-potensiaal bekend is daarvoor om ‘n reënvalgradiënt te volg, verwag mens dat die semi-ariede Karoo ‘n lae KO-potensiaal sal hê. Hierdie gebied bevat egter Spekboom, ‘n buitengewone struiksoort wat koolstof teen soortgelyke tempo’s as woud-ekosisteme opneem, en behoort daarom voordeel uit KU te trek. Akkurate kartering van hierdie plantegroei is kritiek vir akkurate assessering van koolstofvoorraad. Die KO-potensiaal van alle plantgemeenskappe in die studiegebied is derhalwe vasgestel om die koolstofvoorrade in die totale eiendomseenheid te skat. ArcGIS is gebruik om die plantgemeenskappe (sub-biome) te karteer en eCognition is gebruik om die kartering van die Gamkaruigte (wat Spekboom bevat) deur ‘n objek-georiënteerde benadering tot geoutomatiseerde plantegroeikartering te verfyn. Vir akkuraatheidsassessering is ‘n vergelykbare plantegroeikaart per hand versyfer. Die werklike oppervlakte van die gebied is vir die plantegroeiklassifikasie bereken om akkurate oppervlakberekening van die bergagtige terrein te verseker, en hierdie berekende oppervlakte van die gekarteerde plantegroei is gebruik om oppervlakte na koolstofopname-potensiaal te herlei. Advies oor ‘n bemarkingstrategie vir die grondeenhede is gegee, deur die verskillende markte en uitruilings- of handelsmeganismes vir handel in die koolstofmark te ondersoek. Resultate toon dat weens die BLK PNR se geskiedenis van oorbeweiding, Spekboom op die studieperseel gedegradeer het. Dit skep ‘n geleentheid om die plantegroei met befondsing deur KU te herstel. Die opname-potensiaal van Spekboom op BLK PNR is deur ‘n streeksdifferensiasie-vergelyking bepaal. Die streeksdifferensiasie-vergelyking toon dat hoeveelheid reënval en koolstofakkumulasie omgekeerd eweredig of proporsioneel is, en gevolglik veroorsaak meer ariede omstandighede (<200 mm/jaar, of ‘n droë seisoen van langer as sewe en ‘n half maande) dat Spekboom weens waterstres na Crassulacea-suurmetabolisme (CSM) oorskakel, en sodoende die tempo van koolstofakkumulasie verhoog. In natter omgewings, waar Spekboom nie aan waterstres onderwerp word nie, gaan dit voort met koolstofbinding van 3-fosfogliseraat (C3) en het ‘n laer koolstofakkumulasie. Dit is ‘n merkwaardige bevinding aangesien KO daarvoor bekend is dat dit ‘n reënvalgradiënt volg: in hierdie geval is Spekboom ‘n uitsondering op die reël. eCognition het Spekboom swak onderskei, en slegs ‘n ooreenstemming van tussen 64% en 69% met die akkurate hand-geklassifiseerde gehad. Soos verwag, toon vergelykende resultate van driedimensionele oppervlakte dat die werklike oppervlakte byna 10% hoër is as die oorspronklike (en gemete) grondoppervlak van die eiendom. Resultate dui aan dat daar aansienlike koolstofvoorrade vir KU op BLK PNR is. Hierdie studie beveel die mees gebruikte praktyke van KU (herstelproses) vir BLK PNR aan. Oor ‘n hersteltydperk van 30 jaar op BLK PNR kan ongeveer 46 000 ton koolstof opgeneem word. Teen die huidige prys van koolstofkrediete kan dit meer as R3.7 miljoen oor die hersteltydperk van 30 jaar akkumuleer. Die kombinasie van herstelprosesse en bewaringstrategieë in een tipe projek, hou addisionele voordeel in, omdat dit die KO-potensiaal van alle plantgemeenskappe op die grondeenheid en die ekosisteem-dienste in berekening bring. Bewaring van BLK PNR sal 757 913 ton koolstof lewer. As dit in terme van die staking van uitlatings bereken word, kan dit teen R8-10 miljoen gewaardeer word. Die ekonomiese belangrikheid van die ekosisteem en plantgemeenskap-biodiversiteit op BLK PNR impliseer ‘n totale intrinsieke waarde van meer as R800 000 per jaar. Loodsprojekte elders was suksesvol in die verkryging van koolstofkrediete vir die vermyding van ontbossing deur die klimaat-, gemeenskap- en biodiversiteitsalliansie (KGBA). Vanweë die loodsprojekstatus, is daar egter min literatuur beskikbaar wat die berekening van die monetêre waarde van bewaring staaf. Dit laat ruimte vir verdere navorsing.
278

Mapping spatial requirements of ecological processes to aid in the implementation of corridors

Mugwena, Thendo 04 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The ultimate goal of conservation planning is to ensure persistence of biodiversity. Biodiversity patterns and ecological processes are important aspects in conserving biodiversity. Although most researchers in conservation planning have focused on targeting biodiversity patterns, ecological and evolutionary processes can ensure persistence of biodiversity if incorporated into conservation planning. Ecological processes are the main drivers or sustainers of biodiversity. The aim of this research was to identify and map the spatial components of ecological processes in a portion of the Kavango Zambezi Transfrontier Conservation Area to aid in the implementation of biota movement corridors. Different methods have been used to identify suitable corridors but not much has been done on defining and mapping ecological processes that will ensure that the corridors maintain and generate biodiversity. A thorough literature survey was done to make a list of ecological processes that are important in maintaining the biodiversity in the area. Spatial components of ecological processes were mapped as surface elements aligned along linear environmental interfaces or gradients. The last part of the research was to suggest suitable movement corridors based on ecological processes. The results include five spatial components: riverine corridors, areas of high carbon sequestration, edaphic interfaces, upland-lowland interfaces and ecotones. Riverine corridors were mapped using a 1000 m buffer on either side of low lying rivers and 500 m buffer around rivers in the uplands. A map showing the carbon sequestration potential of vegetation in the study area was made using Moderate-Resolution Image Spectroradiometer (MODIS) derived NDVI data and the National Level Carbon Stock dataset done by the Woods Hole Research Center (WHRC) Pantropical. Edaphic interfaces were idenfied using by a 250 m buffer around contrasting soil types. Upland-lowland interfaces identified by a 250 m buffer along upland and lowland habitats. Classification of Landsat 8 was used to identify ecotones in the study area. The results of the spatial components were then compared with the habitat transformation map which shows populated areas. / AFRIKAANSE OPSOMMING: Die uiteindelike doel van bewaringsbeplanning is om voortbestaan van biodiversiteit te verseker. Biodiversiteitspatrone en ekologiese prosesse is belangrike aspekte in die bewaring van biodiversiteit. Alhoewel die meeste navorsers in bewaringsbeplanning fokus op teiken biodiversiteitspatrone, kan die voortbestaan van ekologiese en evolusionêre prosesse van biodiversiteit verseker word deur insluiting in bewaringsbeplanning. Ekologiese prosesse is die belangrikste drywers, of onderhouers, van biodiversiteit. Die doel van hierdie navorsing was dus om die ruimtelike komponente van ekologiese prosesse in 'n gedeelte van die Kavango Zambezi oorgrensbewaringsgebied te identifiseer en te karteer om te help met implementering van biota bewegingsdeurlope. Verskillende metodes is al gebruik om gepaste deurlope te identifiseer, maar min navorsing is gedoen oor definisie en kartering van ekologiese prosesse om te verseker dat die deurlope biodiversiteit sal onderhou en genereer. 'n Deeglike literatuurstudie is gedoen om 'n lys op te stel van ekologiese prosesse wat belangrik is in die handhawing van biodiversiteit in die gebied. Ruimtelike komponente van ekologiese prosesse is gekarteer as oppervlak elemente gebonde aan lineêre omgewingskoppelvlakke of gradiënte. Die laaste deel van die navorsing was om geskikte bewegingsdeurlope, gebaseer op ekologiese prosesse, voor te stel. Die resultate sluit vyf ruimtelike komponente in: rivierdeurlope, gebiede van hoë koolstofsekwestrasie, edafiese koppelvlakke, hoogland-Laeveld koppelvlakke en grensekotone. Rivierdeurlope is gekarteer met behulp van 'n 1000 meter buffer aan weerskante van laagliggende riviere en 500 meter buffer rondom riviere in die hooglande. ‘n Kaart wat die koolstofsekwestrasiepotensiaal van plantegroei in die studie area toon is gemaak met behulp van Moderate-Resolution Image Spectroradiometer (MODIS) afgeleide NDVI data en ʼn koolstofvoorraaddatastel (National Level Carbon Stock dataset) voorsien deur die Woods Hole Research Center (WHRC). Pantropiese edafiese koppelvlakke is geïdentifiseer met behulp van 'n 250 meter buffer rondom kontrasterende grondtipes. Hoogland-Laeveld koppelvlakke is geïdentifiseer deur 'n 250 meter buffer langs die berg en laagland habitatte. Klassifikasie van Landsat 8 data is gebruik om ekotone in die studie area te identifiseer. Die resultate van die ruimtelike komponente is vergelyk met die habitattransformasiekaart wat bevolkte gebiede toon.
279

Carbono orgânico total e frações da matéria orgânica do solo na conversão de cana-de-açucar para eucalipto em Alagoas / Total organic carbon and fractions of organic soil matters at the conversion of sugar cane for eucalytptus in Alagoas

Silva, Anderson Vitor Lins da 08 March 2017 (has links)
The present work had as objective to determine the changes in soil carbon stocks and to evaluate soil organic matter dynamics in eucalyptus forests implanted from the sugarcane area in the state of Alagoas. The study was based on the hypothesis that the conversion of sugarcane with burning harvest system to eucalyptus crop in Alagoas conditions promotes the improvement of the soil quality through the increase of soil organic carbon stocks and the improvement of the soil organic matter dynamic. Therefore, four situations were selected: i) area cultivated with sugarcane (Cana) for approximately 20 years with the manual harvesting and burning system, which was used as reference area; (ii) area under eucalyptus with one year (E1); (iii) area under eucalyptus with three years (E3); iv) area under eucalyptus with six years (E6). Soil samples were collected and analyzed at six depths 0-10, 10-20, 20-30, 30-40, 40-60 and 60-80 cm. Soil density, particle size, soil organic carbon, total nitrogen, microbial carbon, mineralizable carbon, and oxidizable carbon were determined. The results showed that the conversion of sugarcane with manual harvesting and burning for eucalyptus cultivation was efficient in promoting the soil carbon sequestration, as well as improving the soil quality by increasing the levels of soil organic matter and improve their dynamics. More specifically, eucalyptus cultivation with three and six years promoted a substantial increase in soil organic carbon stocks, there was also an increase in the light fraction of organic matter in the soil, and an improvement in the biological indicator qCO2 (metabolic quotient) which suggests that there is a more balanced and favorable environment for soil microbial activity. It is also worth mentioning the decrease in soil density in the treatments E3 and E6, which is another indication of the benefits of the increase in SOM. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente trabalho teve como objetivo determinar as mudanças nos estoques de carbono do solo e avaliar a dinâmica da matéria orgânica do solo em florestas de eucalipto implantadas a partir de área de cana-de-açúcar no estado de Alagoas. O estudo se baseou na hipótese de que a conversão do cultivo de cana-de-açúcar com queima para o cultivo de eucalipto nas condições de Alagoas, promove a melhoria da qualidade do solo por meio do aumento dos estoques de carbono orgânico no solo e da melhoria da dinâmica da matéria orgânica. Com este intuito, quatro situações foram selecionadas para o estudo, foram elas: i) área cultivada com cana-de-açúcar (Cana) por aproximadamente 20 anos com o sistema de colheita manual e queima, a qual foi usada como área de referência do estudo; ii) área cultivada com eucalipto a um ano (E1); iii) área cultivada com eucalipto a três anos (E3); iv) área cultivada com eucalipto a seis anos (E6). As amostras de solo foram coletadas e analisadas em seis profundidades 0-10, 10-20, 20-30, 30-40, 40-60 e 60-80 cm. Foram realizadas as determinações da densidade do solo, granulometria, carbono orgânico do solo, nitrogênio total, carbono microbiano, carbono mineralizável, e carbono oxidável. Os resultados demonstraram que a conversão do cultivo de cana-de-açúcar com colheita manual e queima para o cultivo do eucalipto foi eficiente em promover o sequestro de carbono do solo, assim como, melhorar a qualidade do mesmo por meio do aumento dos teores e estoques de matéria orgânica do solo e melhorar sua dinâmica. Mais especificamente, o cultivo com eucalipto com três e seis anos promoveu substancial aumento nos estoques de carbono orgânico do solo, houve incremento também da fração mais leve da matéria orgânica do solo, e melhoria do indicador biológico qCO2 (quociente metabólico) o qual sugere que existe um ambiente mais equilibrado e favorável a atividade microbiana do solo. Vale ressaltar ainda, a diminuição da densidade do solo nos tratamentos E3 e E6, a qual é mais um indicativo dos benefícios do aumento da MOS.
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Estudo do potencial de sequestro de carbono por restauro florestal em matas ripárias de APPS rurais da UGRHI do Tietê-Jacaré no município de São Carlos - SP

Dias, Roseli Mendonça 27 June 2013 (has links)
Made available in DSpace on 2016-06-02T20:00:52Z (GMT). No. of bitstreams: 1 5313.pdf: 9782065 bytes, checksum: f270ce2e273ed5f7437941eaf648f0cb (MD5) Previous issue date: 2013-06-27 / Financiadora de Estudos e Projetos / The intense greenhouse gas (GHG) emissions into the atmosphere, including Carbon Dioxide (CO2), are the main causes intensifying climate changes. According to Brazil s Forest Code, riparian forests are part of the Permanent Preservation Areas (PPAs) of water bodies, and their primary function regards their preservation, thereby contributing to biodiversity. Moreover, they contribute to minimize the greenhouse effect by promoting carbon sequestration (CO2). Thus, their preservation and/or recovery are the focal point of great concern. The objective of this study is to determine the potential for forest carbon sequestration in riparian forests of PPAs under the Unit for Water Resources Management of the Tietê-Jacaré (UGRHI 13) in the city of São Carlos SP, Brazil. The recuperation of the riparian areas was declared as high priority by the Committee of the Watershed UGRHI 13 in its Watershed Plan. Within this plan, forestry projects under the Clean Development Mechanism (CDM) represent an incentive for reforesting the PPAs of the water bodies of UGRHI 13 and other UGRHIs. The methodology used in this work consisted in the use of visual interpretation of satellite images, field samplings and the development of procedures to classify the degradation levels of the riparian forests into three categories: closed-canopy, open shrubland and predominantly herbaceous. The methodology also included applying a model to determine the Potential Biomass Index (PBI), estimating the carbon dioxide equivalent (CO2e) density, calculating the financial yield from the income of Certified Emission Reductions (CERs) for the forests in the study area, and determining the tCO2e value. For the closed canopy category, approximately 1.372 ha of PPAs with potential sequestration of 175.43tCO2e/ha were found, which would yield CDM of R$456.10 with the current price per tonne in April 2013; for the open shrubland category, approximately 1.573 ha of the PPAs, with a potential of 212.97tCO2e/ha and yield of R$553.70; and lastly, for the predominantly herbaceous category, 388 ha of PPAs, with a sequestration potential of 243.80tCO2e/ha and yield of R$633.90. This indicates that by restoring the still young and degraded forests of these PPAs, they will sequester significant amounts of carbon until they reach their maximum size. The financial revenues obtained by forest carbon sequestration would bear part of the costs of restoring the riparian forests in the PPAs. With the tCO2e values at R$26.00 for the closed canopy category, R$58.00 for the open shrubland category and R$84.00 for the predominantly herbaceous category, companies interested in offsetting their GHG emissions could buy the RECs at the values stipulated, adding their image to the carbon sequestration projects. / As intensas emissões de gases de efeito estufa (GEEs) para a atmosfera, incluindo o Dióxido de Carbono (CO2), passaram a ser o principal motivo da aceleração das mudanças climáticas. As matas ripárias fazem parte das Áreas de Preservação Permanente (APPs) de corpos d água conforme a legislação brasileira e têm como função primordial protegê-los e contribuir para a biodiversidade. Além disso, contribuem para minimizar o efeito estufa pelo sequestro de carbono (CO2) que promovem. Desse modo, tornaram-se alvo de grande preocupação no sentido da sua conservação ou recuperação. Este trabalho visou determinar o potencial de sequestro florestal de carbono em matas ripárias de APPs da Unidade de Gerenciamento de Recursos Hídricos do Tietê-Jacaré (UGRHI 13) no município de São Carlos SP. O restauro florestal das áreas de mata ripária foi indicado como prioridade maior para o Comitê de Bacia da UGRHI 13 em seu Plano de Bacia. Nesse sentido, projetos florestais no âmbito do Mecanismo de Desenvolvimento Limpo (MDL) podem se constituir em um incentivo para o restauro florestal das APPs dos corpos d água da UGRHI 13 e de outras UGRHIs. A metodologia empregada no trabalho consistiu no uso da interpretação visual de imagens de satélite, amostragens de campo e desenvolvimento de procedimentos para a classificação dos níveis de degradação das matas ripárias em três categorias: arbóreo fechado, arbóreo-arbustivo aberto e herbáceo predominante. A metodologia constituiu também da aplicação de um modelo para determinação do Índice de Biomassa Potencial (IBP), estimativa da densidade de dióxido de carbono equivalente (CO2e), cálculo do rendimento financeiro com a comercialização das Reduções de Emissões Certificadas (RECs) para as matas da área de estudo e determinação do valor da tCO2e. Para a categoria arbóreo fechado foram encontrados aproximadamente 1.372 ha de APPs com um potencial de sequestro de 175,43tCO2e/ha, que renderia pelo MDL R$456,10 com o preço da tonelada vigente em abril de 2013; para a categoria arbóreo-arbustivo aberto, aproximadamente 1.573 ha de APPs, com um potencial de 212,97tCO2e/ha e rendimento de R$553,70; e por último, para a categoria herbáceo predominante, 388 ha de APPs, com um potencial de sequestro de 243,80tCO2e/ha e rendimento de R$633,90. Isso permite concluir que com o restauro florestal dessas APPs as florestas, ainda jovens e degradadas, sequestrarão quantidades significativas de carbono até atingir o porte máximo. O rendimento financeiro obtido com o sequestro florestal de carbono arcaria parcialmente com os custos do restauro florestal das matas ripárias em APPs. Com o valor da tCO2e a R$26,00 para a categoria arbóreo fechado, R$58,00 para a categoria arbóreo-arbustivo aberto e R$84,00 para a categoria herbáceo predominante, empresas com o interesse de compensar suas emissões de GEEs poderiam comprar as RECs a estes valores estipulados, agregando sua imagem aos projetos de sequestro de carbono.

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