Spelling suggestions: "subject:"ecosystem,"" "subject:"cosystem,""
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What Would a Waterbird Do? An Annual Study of 13 Urban Wetlands in Frisco, TexasProctor, Jayce Alan 05 1900 (has links)
Intention for this study is driven by finding patterns that may be shown to reveal primary factors of influence for the abundance and diversity of wetland birds. These correlations may be used to promote wetland management strategies for the benefit of waterbird species, and help illuminate current local wetland conditions for waterbirds, respectively. The idea is to help enliven individuals to become a more conscious steward and manipulator of our environment through incorporating structural and biological components into wetland development and management strategies, and broadly speaking, urban development practices.
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Implementing Ecosystem Natural Capital Accounting Methodology to the Rhone watershed : the proof-of-concept / Application de la comptabilité écosystémique sur le bassin versant du Rhône : validation du conceptArgüello Velazquez, Jazmin Adriana 16 September 2019 (has links)
Comment mesurer la dégradation de la nature, son état de "santé", afin de déterminer l’amortissement de son utilisation, non-enregistré dans les bilans des nations? Mon travail de thèse sur la « comptabilité écosystémique » du bassin versant du Rhône est une première expérimentale sur une nouvelle méthodologie intégrable aux outils encore incomplets des comptabilités nationales de type PIB. Consommer du capital écologique, nos ressources renouvelables, sans l’amortir revient à créer des dettes écologiques. L’objectif de la comptabilité écosystémique est de produire un outil d’aide à la décision permettant d’éviter la dégradation nette des écosystèmes par des politiques publiques informées par la science. L’outil produit des bilans écologiques basés sur des informations géographiques et mesurés en termes physiques, permettant d’effectuer des modélisations et simulations afin d’estimer l’internalisation des externalités (Figure). J’ai élaboré divers indicateurs synthétiques relatifs aux fonctions des écosystèmes et de leur intégrité, pour calculer le potentiel écologique du bassin versant du Rhône. Le diagnostic comptable est assortie d’une description spatialisée des changements observés afin de mieux saisir leur pertinence. L’outil est susceptible d’aider les différentes entités territoriales à se positionner sur la gestion de leurs ressources renouvelables stratégiques (eau, sols, biomasse, infrastructures et services écologiques) dans le contexte d’un ordre mondial en transformation: il s’agit des enjeux géopolitiques majeurs en matière de sécurité et souveraineté alimentaire et énergétique, dans leur lien avec la santé publique. / How to measure the degradation of nature, its "health" condition, to determine the depreciation of its use, not recorded in the balance sheets of the nations? My thesis work on the "ecosystem accounting" of the Rhone river basin is an experimental first on a new methodology integrable with the still incomplete tools of the national accounts of the type GDP. Consuming ecological capital, our renewable resources, without amortizing means the creation of ecological debts.The goal of ecosystem accounting is to produce a decision support tool to avoid the net degradation of ecosystems through science-informed public policies. The tool produces ecological balances based on geographical information and measured in physical terms, making it possible to perform modelizations and simulations in order to estimate the internalisation of externalities (Figure). I have developed various synthetic indicators relating to the functions of ecosystems and their integrity, to calculate the ecological potential of the Rhône watershed. The accounting diagnosis is accompanied by a spatial description of the changes observed in order to better understand their relevance. The tool is likely to help the various territorial entities to position themselves on the management of their strategic renewable resources (water, soil, biomass, infrastructures and ecological services) in the context of a changing world order: major geopolitical issues in terms of security and food and energy sovereignty, in their link with public health.
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Evaluating trade-offs between agricultural productivity and long-term ecosystem services provision among maize farmers practising conventional and conservation agriculture in Kafue ZambiaMwangana, Namulula January 2016 (has links)
Maize is a staple crop and underpins food security for Zambia. Maize productivity in Zambia is almost half the potential due to low uptake of conservation agricultural practices. This study tests the hypothesis of the trade-offs between agriculture productivity and long-term ecosystem services (ES) provision among maize farmers practising conventional agriculture on the one hand, and those practising conservation agriculture on the other hand, in Kafue district, Zambia. In addition, challenges which affect conservation agriculture uptake are assessed. Besides these challenges, the study notes that adoption of a new technology is also influenced by its efficiency, and therefore technical efficiency scores were estimated using the Stochastic Frontier Approach (SFA) to compare efficiency levels of the two agricultural systems. Kafue was purposefully selected as it is among the first districts where conservation agriculture was introduced. Through purposive and random sampling, the households surveyed were split into two distinct groups namely conservation agriculture (CA) farmers (treatment group) and conventional agriculture (CV) farmers (control group).
The analysis significantly shows that farmers practicing CA have more knowledge than CV farmers about the capacity of conservation agriculture to reduce soil erosion, increase soil fertility, retain nutrients, mitigate pests and weeds and increase crop yield. However, both farming groups knew that CA helps conserve soils and that soil maintenance is important for food production. On the other hand, significantly, CV farmers knew more than CA farmers that CV reduces crop yield and increases soil erosion. On the other hand, CV farmers expressed a higher level of willingness to adopt CA practices than CA farmers who are unwilling to expand their area under CA. The study further shows that at least 55% of farmers practicing CA find inadequate labour to be the main challenge faced in CA. It appears that a policy that improves the farmers' knowledge on CA would help improve the uptake of CA.
CA farmers were significantly more knowledgeable than CV farmers about the detrimental effects of CV, such as increasing air and water pollution, thus raising the need for training among CV farmers with emphasis on the effects of their farming system on the environment which affect the supply of ecosystem services.
Efficiency is also a means of improving productivity hence the Stochastic Frontier Analysis (SFA) was employed to estimate technical efficiency levels in maize production. Using SFA, the study found that the technical efficiency of maize among CV farmers is 71.3% on average while that of CA farmers is 57.9% on average. Moreover, the study found that there was a significant difference (t=3.9854, P=0.0002) in the technical efficiency scores of the both CV and CA farmers. Nevertheless, the study also found that 77% of output variation among CA farmers can be explained by variation in technical efficiency. However, 33.4 % of total maize output can be explained by variation in technical efficiency among CV farmers. This means that CA farmers have a higher potential to increase their current output than CV farmers.
Finally there was no significant difference in fertiliser usage between CA and CV farmers (t=1.3825, P=0.1700). Further, from SFA fertiliser responsiveness to maize output showed that a 1% increase in the use of synthetic fertiliser leads to 0.678% and 0% increase in maize output per hectare for CA and CV respectively at both 1% and 10% level of significance at the expense of water and air quality. Therefore, it can be concluded that there is a higher trade-off between maize production and water and air quality under conventional than under conservation agriculture. / Dissertation (MSc (Agric))--University of Pretoria, 2016. / Agricultural Economics, Extension and Rural Development / MSc (Agric) / Unrestricted
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The Prolific Partition : Architecture as catalyst for nature reserve conservation structured in the in-between of Urban and NatureVisagie, Armand 04 1900 (has links)
Nature reserves in the City of Tshwane are under threat from ecological and historically significant decay due to the less defined nature of these landscapes. Architecture in form, function and technology can be developed in the in-between of nature and urban to act as conservator for these nature reserves. Utilizing the natural resources of nature to produce products for the urban dweller within a space that conserves the historical protective layers of the site. The space of interaction between nature and urban becomes the conservator, acting as active protector in terms of sustainable production, education and urban dweller interaction with the nature reserve and its continuous history of protection. / Natuurreservate in die stad Tshwane word bedreig deur ekologiese en historiese betekenisverval weens die minder gedefinieerde aard van hierdie landskappe. Argitektuur in vorm, funksie en tegnologie kan ontwikkel word in die tussen
ruimte van natuur en stedelike gebiede om as natuurbewaarder vir hierdie natuurreservate op te tree. Die natuurlike hulpbronne van die natuur kan gebruik word om produkte vir die stedelike inwoner te produseer binne ‘n ruimte wat die historiese beskermende lae van die terrein laat voortduur. Die ruimte van interaksie tussen natuur en stedelike word die bewaarder, wat optree as ‘n aktiewe beskermer in terme van volhoubare produksie, opvoeding en stedelike inwoner interaksie met die natuurreservaat en sy voortgesette geskiedenis van beskerming. / Mini Dissertation (MArch(Prof))--University of Pretoria, 2018. / Architecture / MArch(Prof) / Unrestricted
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Development of calcium stable isotopes as a new tool to understand calcium cycling in terrestrial ecosystemsTakagi, Kenneth Andrew 28 November 2015 (has links)
Calcium stable isotope ratios are a relatively new tool that biogeochemists can use to investigate the biogeochemical cycle of calcium in terrestrial ecosystems, having seen widespread application only in the past 15 years. To advance the application of calcium isotopes in biogeoscience research, I conducted three investigations focused on interpreting calcium isotope ratios in streamwater and in the cation exchange pool of forest soils.
In the first study, we observe a shift toward lower 44Ca/40Ca ratios in streamwater draining a New Hampshire watershed after an experimental clearcutting event. Isotope ratio measurements of ecosystem calcium pools indicate that enhanced leaching of the soil exchangeable pool produced the observed shift in 44Ca/40Ca ratios. A trend towards decreased 44Ca/40Ca ratios in soils in the years following the harvesting indicates that calcium leached from the soil exchangeable reservoir was likely replaced by calcium released by the decay of belowground biomass, maintaining pre-harvest levels of exchangeable calcium even in the face of a significant ecosystem disturbance.
In a second study, we observed significant differences in the 44Ca/40Ca of the soil exchange pool between two neighboring tropical watersheds, although 44Ca/40Ca of calcium inputs (bedrock and atmospheric deposition) at the two sites were indistinguishable. Further, both sites had higher 44Ca/40Ca ratios compared with external inputs, a relatively rare observation globally. We propose that hurricane disturbance best explains the high 44Ca/40Ca at each site, and that the difference in 44Ca/40Ca between the two sites can be accounted for by the magnitude of disturbance at each site.
Finally, a synthesis of our new data with previously published results shows that globally, soil exchangeable 44Ca/40Ca ratios can be higher, lower or equal to external inputs. Modeling work indicates that in addition to isotopic fractionation, the balance in fluxes between vegetation and soil is critical in determining how soil exchangeable 44Ca/40Ca ratios vary relative to external inputs. When plant uptake and return to the soil are equal, soil and external inputs 44Ca/40Ca are equal, while high soil 44Ca/40Ca ratios develop when uptake exceeds return. Soil develops low 44Ca/40Ca when biomass obtains calcium from sources other than the exchangeable reservoir.
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Distribution of epifauna in offshore benthic environments along the west and south coast of South AfricaShah, Aliya 22 February 2019 (has links)
Marine unconsolidated sediments, such as sand, gravel and muds, constitute the most extensive benthic ecosystems globally. Biological data for these ecosystems are frequently sparse which can hinder the success and implementation of marine management strategies for benthic ecosystems. There are limited studies in South Africa on benthic epifauna. This study investigates the composition and distribution of epibenthic invertebrate assemblages along the west and south coast of South Africa (sampled using depth-stratified demersal trawls) to inform marine environmental management. Sample depth varied from 36m to 899m. Multivariate tools (PRIMER and PERMANOVA+) were used to analyse spatial (west vs south coast) and temporal (2011 vs 2017) patterns in epifauna. This study also investigated an overlap region between the west and south coast. A group average linkage cluster analysis defined biotopes using significant branching (p< 0.05). Biotopes were compared against the
2012 National Biodiversity Assessment (NBA) benthic habitat map to investigate
whether epifaunal biotopes identified, align with the existing classification. A significant
difference among epifauna between region and depth was found, where the west
coast had a higher average number of individuals and species per station.
Sympagarus dimorphus and Pelagia noctiluca were characteristic species for west
and south coast respectively. Epifauna was found to be significantly different between
2011 and 2017, with a notable increase in the abundance of Crossaster penicillatus in
2017. The majority of the biotopes aligned with the current NBA classification, in
particular the Agulhas Sandy Shelf Edge ecosystem type on the south coast and South
Atlantic Upper Bathyal and Namaqua Muddy Inner Shelf ecosystem types on the west
coast. This thesis contributes to the mapping and description of offshore ecosystem
types to inform marine environmental impact assessments, marine spatial planning
and marine protected area expansion.
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Enterprise architecture driven design of an artefact to support strategic Information Technology decision-making of Small Enterprises in Nigeria and South AfricaAlhassan, Mohammed 08 August 2018 (has links)
Information Technology (IT) is inevitably influencing the way enterprises operate, compete, and grow. The contemporary disruption has not excluded small companies. Small enterprises play a significant role in the growth of every economy but are hindered by limited skills, time, and money. The attributes of small enterprises influence the strategic and day-to-day operations. Small enterprise owners are often the managers who make the strategic decisions in order to solve specific problems. The decision style of small enterprise owner-managers limits the leveraging of IT. To ensure the sustainability of small enterprises in a contemporary business ecosystem, it is pertinent to strategise IT investment decisions. Enterprise architecture is a well-known approach to business and IT alignment. This study aimsto discover and develop how the complex enterprise architecture principles can strategise the IT decisionmaking process in small enterprises with limited resources and informal structures. The pragmatic philosophic stance was the premise for understanding the decision challenges and the development of a roadmap to intervene the problems the researcher identified. The Vaishnavi and Kuechler design science research methodology guided this study. The qualitative research approach was employed to collect verbal data with eleven small enterprise ownermanagers to understand the processes and the challenges of making IT decision in small enterprises. A thematic analysis of the findings revealed that lack of formalisation, limited information, and lack of IT skill created a critical bottleneck of IT investment decisions in small enterprises. An enterprise architecture-driven framework was developed to overcome the bounded rationality approach to IT choices in small enterprises. The framework holistically assesses organisational business-IT capabilities, constraints, and criteria to guide the decisionmaker's choice. The characteristics of small enterprises limit the successful implementation of the enterprise architecture-driven framework as a theoretical guideline for making optimal IT decisions in small enterprises. This study further developed an online IT decision-assistive tool informed by the framework. The instantiation artefact was demonstrated with six small enterprise owners from Nigeria and South Africa. The findings affirmed the prospect, potential, and relevance of an enterprise architecture-driven artefact as a tool to optimise strategic IT decisions in small manufacturing, service, and retail enterprises. The artefact developed in this study provided a practical intervention to the challenges of IT investment decisions in small enterprises.
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Functional Diversity of Red Sea Coral Reef Fish Assemblages in Northern Saudi ArabiaFord, Kiana 04 1900 (has links)
As a part of Saudi Arabia’s Vision 2030, the Al Wajh Bank will soon undergo major
coastal development to be transformed into a sustainable luxury tourist destination, with
goals to safeguard the marine and coastal habitats in order to achieve a net conservation
benefit of 30%. To realize these objectives, it is essential to establish baseline data on the
marine communities to gauge the success of conservation goals. In this study, we
evaluated and compared the taxonomic and functional diversity of reef fish assemblages
between two areas in the Al Wajh Bank, sites inside the lagoon and those outside of it, in
order to establish differences in fish communities across environmental gradients.
Conditions within the lagoon, such as temperature and salinity, have been shown to differ
from most other Red Sea areas and are thought to result in unique fish assemblages.
Underwater assessments of fish communities and benthic composition were conducted
throughout the Al Wajh Bank during cruises in 2016 and 2017. We found that of the 168
fish species recorded, 75 species were exclusive outside the lagoon, 22 were exclusive
inside the lagoon, and 71 species were shared between inside and outside. Sites within the
lagoon had significantly less species richness as well as lower abundances. While
taxonomic composition differed between the two areas, functionally they were very
similar. Two functional metrics (functional richness and functional dispersion) indicated
different levels of functional diversity, while two other metrics (functional evenness and
functional specialization) showed no differences in functional diversity. The outside had
five groups comprising eleven species with functional redundancy; in contrast, the inside
had two species which were functionally redundant. This study was able to establish that
the inside and outside habitats are different and have dissimilar species compositions, yet
the functional characterization of fish assemblages in conserved. These results advocate
for the use of functional diversity metrics as a way to evaluate changes to community
composition, and is an initial assessment towards tracking changes in the fish
communities as coastal development progresses
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Kartläggning av ekosystemtjänster i ÅresjönEriksson Norman, Emma January 2019 (has links)
Den utökade verksamheten i Åre har lett till en försämrad ekologisk status för den lokala sjön i Åre vid namn Åresjön. Enligt länsstyrelsen Jämtlands län så finns behovet av att åtgärder vidtas för att förbättra tillståndet i sjön. Denna studie har som syfte att bidra med information till framtida beslutsunderlag. Metoden som användes för att utföra studien valdes för att undersöka vilken data som finns tillgänglig för de olika ekosystemtjänsterna samt hur tillgänglig den informationen är. Studien utgick från enbart befintliga data samt en metod som används för att undersöka vilka indikatorer som finns kopplade till nyttjandet av ekosystemtjänsterna från Åresjön. Resultatet visar på att det finns flera ekosystemtjänster i Åresjön som har användarvärde i dagsläget. Vissa av de tjänsterna som belyses i studien har varit svåra att påvisa på grund av otillfredsställande tillgänglighet av information. Det finns flera indikatorer som visar på att ekosystemtjänsterna kopplade till Åresjön nyttjas i dagsläget. Slutsatserna av studien är att det finns ekosystemtjänster kopplade till Åresjön som idag har ett användarvärde men i och med att informationen om tjänsterna är begränsade så kan det inte utföras en komplett kartläggning av tjänsterna och dess värden. / The expanded operations in Åre have led to a deterioration of the ecological status of the local lake in Åre, named Åresjön. According to the county administration of Jämtland, there is a need for measures to improve the state of the lake. This study aims to provide information for future decision making. The method used to carry out the study was chosen to investigate what data is available about the different ecosystem services and how accessible that information is. The study was based on only existing data. Another method used in the study examines which indicators are linked to the use of ecosystem services from Åresjön. The result shows that there are several ecosystem services in Åresjön that have user value at the present time. Some of the services highlighted in the study have been difficult to detect due to unsatisfactory availability of information. There are several indicators that show that ecosystem services connected to Åresjön are currently being used. The conclusions of the study are that there are ecosystem services connected to Åresjön, which today have a user value, but because the information about the services is not limited, a complete mapping of the services and its values cannot be performed. / <p>2019-06-07</p>
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The Music-Maker: An Architectural Network for Exploration of Self and ExpressionKonstantinou, Lauren Mary 12 1900 (has links)
This dissertation explores the impact of providing platforms for school learners to positively express themselves through multiple educational activities, in turn, developing a collective identity through performance. The existing school typologies in Mamelodi East, Pretoria, are found to hinder such explorative and all-round inclusive activities, resulting in the exclusion of many types of learners. Through a filter of music-making, the architecture of Tsako Thabo Secondary School in Mamelodi East has been assessed to have inadequate spaces and cause a disconnect with the community. Identified through literature, there is an opportunity to investigate the connection between music-making, participation and architecture as a way of transforming both the social and physical aspects of the school and surrounding community.
The proposed intervention networks between existing nodes of music-making. With a focus on the node of Tsako Thabo Secondary School, an expressive architectural language is used to provide platforms for inclusive and adaptable
educational and social activities. This language ripples out through the built fabric of the community and creates a sense of identity through the intersection of music and architecture. This dissertation uses participatory research in order to identify real world problems and social agents of change within the community. Furthering participation, codesign methods are used to influence the iterative design process to work beyond the single author limitations and remain contextually and socially relevant throughout. This was largely affected by the COVID-19 pandemic, proving resilience and adaptability for the approach, relevant for current research methodologies. / Mini Dissertation (MArch (Prof))--University of Pretoria, 2020. / This dissertation is a result of the investigation and the UkuDoba research methodology developed in the NRF project, STINT: Stitching the City (2020). This was a collaborative effort between the University of Pretoria and Chalmers University in Gothenberg, Sweden. / Architecture / MArch (Prof) / Unrestricted
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