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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.
41

The response of bark-gleaning birds and their prey to thinning and prescribed fire in eastside pine forests in Northern California /

Rall, Christopher James. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 91-97). Also available via Humboldt Digital Scholar.
42

Regeneração natural de fragmentos de florestas nativas inseridos em paisagens agrícolas muito fragmentadas do noroeste de São Paulo / Natural regeneration of native forest fragments in highly fragmented agricultural landscape of northwest São Paulo

Pablo Hugo Alves Figueiredo 02 December 2016 (has links)
O noroeste de São Paulo, transição entre a Floresta Atlântica e o Cerrado, é uma das regiões mais fragmentadas do estado. Investigando a regeneração natural de remanescentes florestais é possível compreender como a diversidade de espécies e os processos ecológicos são mantidos nessas paisagens agrícolas muito fragmentadas, gerando subsídios para ações de conservação e restauração. Nesse sentido, as perguntas norteadoras deste estudo foram: 1) o conhecimento do componente regenerante de remanescentes florestais inseridos em matrizes agrícolas muito fragmentadas permite avaliar a perpetuação dos mesmos ao longo do tempo? 2) quais fatores, de qualidade de hábitat ou de estrutura da paisagem, exercem maior influência sobre composição, densidade e riqueza de espécies no componente regenerante desses remanescentes florestais? Para isso, foi comparada a riqueza, diversidade e composição de espécies entre o componente regenerante (altura >1,0 m e DAS< 5 cm) e arbóreo (DAS> 5 cm) de 18 fragmentos de florestas nativas do noroeste de São Paulo. Em seguida, foi analisada a relação entre a qualidade do hábitat (soma de bases do solo, teor de argila do solo e frequência de incêndio) e estrutura da paisagem (conectividade, isolamento e tamanho total do fragmento) com os valores descritivos do componente regenerante. Foram registrados no componente regenerante 5.989 indivíduos e 207 espécies, o que equivale a uma média de 4968±3584 ind.ha-1 e 33±14 espécies por fragmento. As famílias mais ricas foram Fabaceae (28 espécies), Myrtaceae (25), Rubiaceae (21) e os gêneros foram Eugenia (12), Ocotea (6), Campomanesia (5) e Psychotria (5). Comparado ao componente arbóreo, o componente regenerante apresentou significativamente menor riqueza e diversidade &alpha;, pois 71% das espécies do componente arbóreo não foram registradas na regeneração natural. Porém, ambos componentes apresentaram composição florística significativamente correlacionada. Com relação à diversidade &beta;, em média, o componente regenerante apresentou valor significativamente maior entre os fragmentos. A qualidade de habitat foi mais importante para explicar a estrutura e riqueza da comunidade regenerante. Frequência de incêndio contribuiu negativamente para a densidade total comunidade e de indivíduos zoocóricos, clímaces de sub-bosque e de dossel, assim como para a riqueza de espécies zoocóricas, pioneiras e colonizadoras. A riqueza de especialistas de florestas apresentou relação positiva com a soma de bases enquanto para a riqueza e densidade de generalistas a relação foi negativa. Soma de bases e teor de argila no solo foram as variáveis mais relacionadas com a composição florística da comunidade regenerante. Dentre as variáveis de paisagem, conectividade relacionou-se negativamente com a densidade de espécies generalistas enquanto área do fragmento apresentou relação positiva com a densidade de zoocóricas com propágulos de tamanho médio. Portanto, a regeneração natural representou um subconjunto de espécies do componente arbóreo com menor diversidade, riqueza e número de espécies compartilhadas entre os fragmentos e por isso seriam necessárias ações de manejo adaptativo para garantir a perpetuação dos remanescentes florestais nessas paisagens muito fragmentadas. Frequência de incêndios foi o principal fator comprometedor da perpetuação da biodiversidade e a importância do gradiente edáfico para composição de espécies dos remanescentes florestais da região foi confirmada. / The northwestern São Paulo, a transition area between the Atlantic Forest and Cerrado, is one of the most fragmented region of the state. Investigating the sapling community of forest communities would be possible understanding how species diversity and ecological processes are maintained in this kind of landscape and therefore it would help creating subsides for forest restoration. For this reason, the questions of this research were: 1) Does the survey of sapling community of forest remnants in highly fragmented agricultural landscape allows assessing their self-perpetuating capacity? 2) Which factors of habitat quality or landscape structure exerts greater influence on the species composition, density and species-richness of the sapling community of these forest remnants? Thus, it was assessed the sapling community (height >one, 0 m and DSH< 5,0 cm) density and compared the observed and the relative species-richness of functional groups, &alpha; and &beta; diversity and species composition to the tree community (DSH> 5,0 cm) in the same forest remnant. After that, was assessed the influence of habitat quality (soil sum of bases, soil clay content, fire frequency) and landscape structure (functional connectivity, isolation and total size of these forest remnants) on the descriptive values of sapling communities. Overall, the sapling community showed 5.989 individuals and 207 species that represent on average 4968±3584 ind.ha-1 and 33±14 species for forest fragments. The botanic families with higher species-richness were Fabaceae (28 species), Myrtaceae (25), Rubiaceae (21) and genera were Eugenia (12), Ocotea (6), Campomanesia (5) e Psychotria (5).Compared to the tree community, the sapling community had significantly smaller species-richness (observed and estimated) and &alpha; diversity, because 71 % of species from the tree community did not occur in sapling community. However, both communities had species composition significantly correlated, the sapling communities showed significantly higher &beta; diversity than trees communities. The habitat quality were more important to explain the density, species-richness and species composition of the sapling communities. Fire frequency contributed negatively to species-richness of zoochorous species, pioneer species and colonizers group (species found only at sapling community) and to the sapling density of zoochorous species, shade-tolerant canopy species and shade-tolerant understory species. The species-richness of forest-specialist species was positively related to the soil sum of bases but to the sapling density and species-richness of generalist species was found the opposite relation. Similarly, sum of base and clay content were the variables most related to the species composition of sapling community. Functional connectivity and the total area of the forests fragments explained only the density of generalist and zoochorous medium-seeded species, but with relatively smaller importance than the habitat quality variables. Thus, the sapling community of these forest remnants represented a subset of the tree community but with significant smaller diversity, species richness and number of common species among fragments and then adaptive management efforts is needed to assist long-term biodiversity persistence in forests fragments in highly fragmented agricultural landscape. Frequent fires was the main factor affecting negatively the biodiversity perpetuation and the importance of an edaphic gradient to species composition of forests remnants in the region was validated.
43

Achieving Next Generation Environmental Impact Assessment Follow-up and Monitoring

Andronak, Brett 17 April 2017 (has links)
Despite growing scrutiny of Environmental Impact Assessment (EIA) in Canada and worldwide, the follow-up and monitoring component remains under practiced, leaving EIA decision-makers and practitioners with little understanding of the accuracy of impact predictions made and the effectiveness of mitigation measures developed during the EIA project-planning phase. The Minister’s Expert Panel further highlighted the importance of enhancing follow-up and monitoring during the recent review of EIA processes in Canada. The research identifies six leading edge practices for next generation EIA follow-up and monitoring: public and Indigenous participation, continuous learning, clear roles and responsibilities, independent oversight, adaptive management and traditional knowledge. Approaches to implement those practices in a Canadian context are explored and supported by guidance that captures the learning potential of EIA follow-up and monitoring. The six practices are intended as a package and are presented with practical guidance for proponents, regulators, consultants and others involved in EIA. / May 2017
44

Dynamique et conservation des populations difficilement observables : cas d'étude de la recolonisation du loup dans les Alpes françaises / Population dynamics and conservation of elusive species : recolonization of the French Alps by the wolf

Marescot, Lucile 03 December 2012 (has links)
En Europe, la présence de grands carnivores dans des paysages anthropisés entraîne une forte compétition avec l'homme et alimente d'importantes polémiques concernant leur protection légale. La perception antagoniste de ces espèces à la fois emblématiques pour certains et sources de conflits pour d'autres, rend la gestion de leurs populations très délicate. Depuis la recolonisation spontanée du loup (Canis lupus) dans les Alpes françaises au début des années 1990, la population s'est accrue numériquement et spatialement. Parallèlement, les dégâts occasionnés par le loup sur la filière élevage ont suivi la même tendance. L'Etat met en place aujourd'hui un contrôle raisonné de la population, sous réserve que les objectifs de conservation, exigés par la Directive Habitat, soient respectés. En s'inspirant du cas d'étude du loup en France, nous proposons dans cette thèse un cadre de prise de décision structurée adapté pour la gestion et la conservation d'espèces rares et difficilement observables, protégées par des accords législatifs mais qui, dans un contexte social conflictuel, peuvent être régulées. La modélisation séquentielle du processus décisionnel s'est déroulée dans un contexte de forte incertitude selon plusieurs étapes : 1) appréhender les objectifs de conservation et/ou contrôle du loup en France pour les formaliser sous forme mathématique via une fonction d'utilité, 2) suivre la population par une méthode non-invasive pour définir des indicateurs de gestion fiables et évaluer le statut de conservation de la population, 3) coupler les mesures létales adoptées actuellement à un modèle démographique décrivant la dynamique du loup et intégrant sa structure sociale, 4) et déterminer la décision. Cette dernière étape est réalisée à l'aide d'une méthode d'optimisation qui calcule la stratégie optimale de gestion en fonction de la structure sociale de la population et des différentes sources d'incertitude accumulées à chaque étape du processus décisionnel. Nous avons choisi comme indicateur de gestion le taux de croissance, à partir duquel nous avons défini l'utilité. Cet indicateur était robuste à l'incertitude d'échantillonnage émergeant de la détection partielle et hétérogène des individus. Des analyses de sensibilité de la décision ont montré une forte influence de la fonction d'utilité sur la stratégie optimale, soulignant ainsi l'importance de définir correctement les objectifs. Nous avons également montré que la stratégie optimale était sensible aux variations des paramètres démographiques, montrant ainsi l'intérêt des méthodes de capture-marquage-recapture pour les estimer correctement. Nous discutons enfin de l'extension de notre approche à un cadre décisionnel de gestion adaptative pour traiter des problèmes de conservation dans un contexte conflictuel. / Large carnivore management in Europe is controversial because of conflictive objectives arising from the legal protection of threatened species vs. the possible necessity of culling individuals to prevent severe damages on human activities. Since the wolf recovery in the French Alps in the early 90's, the population has been numerically and spatially increasing. In parallel, livestock depredations have been following the same trend. As an EU member state, France is bound to the European Habitat Directive, which provides full protection of wolf populations and their habitat. Nevertheless, derogatory killings are allowed for individuals causing problems on livestock and some lethal control is now incorporated into the national management plan, as long as the population growth and its distribution range are not being threatened. Illustrating with the case study of the wolf in France, my dissertation proposes a structured decision making framework for the management and the conservation of elusive species that are legally protected but, in a conflictive context, are subject to population control. The sequential modeling of our decision process occurred in the following steps: 1) define the multiple objectives and formulate them in terms of a utility function, 2) monitor the population through a non-invasive approach in order to define the population conservation status, 3) build a demographic model to predict the consequences of harvesting on population dynamics and social structure, 4) obtain optimal state-dependent decisions. The last step is done with stochastic dynamic programming (SDP), acknowledged to be one of the most useful optimization methods in decision making. We provide an optimal solution for wolf management that gives the highest chance of meeting objectives, defined on population growth rate. This demographic indicator was found to be robust to sampling uncertainty arising from partial and heterogeneous detection of individuals. We ran decision sensibility analyses and found a strong effect of the utility function on the optimal strategy, highlighting the importance of defining explicit objectives. We also found that the optimal strategy was sensitive to demographic parameters, which demonstrate the general need of using solid statistical approaches to estimate them properly. This structured decision making framework can further be extended to adaptive management, acknowledged as being a convenient framework for wildlife management.
45

Coastal Land Loss and Collaborative Resource Governance: The Case of Plaquemines Parish, Louisiana

Seth, Nandini 18 December 2014 (has links)
The research, presented here, is about the collaborative governance and adaptive management in coastal planning efforts of Louisiana. Fundamental conflict, between the idea of environmental conservation and developmental growth, has always existed in the coastal regions. The presence of the large number of environmental laws, at various levels of government and their different management objectives for utilization of coastal resources, requires study of intergovernmental relationship. Taking Plaquemines Parish as a case in point, this thesis will, therefore, review the critical restoration plans for intergovernmental coordination and conflicts. It will also provide recommendations, for elected representatives and policy makers, with an aim to promote collaborative governance and improve adaptive management of coastal resources.
46

A regeneração natural como indicadora de conservação, de sustentabilidade e como base do manejo adaptativo de fragmentos florestais remanescentes inseridos em diferentes matrizes agrícolas / Natural forest regeneration as an indicator of conservation, sustainability and as the basis of adaptive management of forest remnants embedded in different agricultural matrices

Mangueira, Julia Raquel de Sá Abilio 19 June 2012 (has links)
O cenário atual do estado de São Paulo reflete o cenário de degradação observado na Floresta Atlântica do país, onde os remanescentes florestais estão muito fragmentados, degradados e imersos em uma paisagem agrícola, dominada predominantemente por matrizes de cana de açúcar e pastagens. Neste contexto, objetivamos investigar se a regeneração natural da borda de fragmentos florestais tem características distintas nessas duas matrizes agrícolas dominantes. Nossa hipótese foi que de a regeneração natural em fragmentos inseridos em matrizes de cana de açúcar e pastagem são distintas, porque essas matrizes definem diferentes trajetórias de degradação sobre a flora de fragmentos naturais. Este trabalho foi desenvolvido na bacia do rio Corumbataí, onde indivíduos de espécies arbustivo e arbóreas do estrato regenerante (mínimo de 30cm de altura até 15 cm de perímetro à altura do peito) foram amostrados em 60 transectos de 30x2m (subdivididos em transectos contíguos de 10x2m) sistematicamente distribuídas a partir da borda de 12 fragmentos selecionados na bacia. Primeiramente, foi feita uma caracterização florística geral da regeneração natural das bordas de fragmentos florestais inseridos nas duas matrizes agrícolas. Posteriormente, foram utilizadas as variáveis número de indivíduos.hectare-1 (RN_HA) e número de espécies/m2 (NESP_M2) e diversidade florística (ISHANNON) para analisar as diferenças da estrutura e composição da regeneração natural nas duas matrizes. Essas mesmas variáveis foram utilizadas para analisar estatisticamente o efeito de indicadores de conservação dos fragmentos, como entrada de gado, presença de eucaliptos no dossel e abundância de gramíneas e lianas, sobre a regeneração natural. A similaridade florística entre remanescentes das paisagens foi calculada através do Índice de Similaridade de Jaccard. Em todos os transectos, foram amostrados 5886 regenerantes, divididos em 58 famílias, 220 espécies e 18 morfoespécies. O índice de Jaccard mostrou que houve similaridade florística (45%) entre os regenerantes dos fragmentos da matriz de pastagem e cana de açúcar. Nos fragmentos inseridos na matriz de pastagem, a entrada de gado foi o indicador de conservação de fragmentos que apresentou maior interferência sobre a regeneração natural, diminuindo tanto o número de indivíduos por unidade de área quanto a diversidade florística. Para a paisagem de cana, a fonte de variação que mais interferiu na estrutura da regeneração foi a presença de eucaliptos no dossel, que aumentou o número de indivíduos por unidade de área. A abundância de gramíneas e lianas e a presença de epífitas não apresentaram influência sobre a regeneração quando analisados tipo de matriz ou tamanho do fragmento. Entre os sub-transectos contíguos de 10m, não houve variação na estrutura e composição da regeneração natural, indicando que nesta profundidade de borda a vegetação regenerante é homogênea quanto à florística, diversidade e classificação sucessional. Os resultados indicam que, mesmo inseridos em paisagens agrícolas profundamente antropizadas, os remanescentes florestais ainda detém elevada diversidade florística. A regeneração natural mostrou-se um bom indicador de qualidade atual e futura dos remanescentes florestais, e demonstrou, juntamente com os indicadores de conservação, que os fragmentos são passíveis de manejo, o que poderá potencializar o papel de conservação da biodiversidade exercido pela regeneração natural. / At São Paulo state, Brazil, the scenario of the Atlantic Forest reflects the scenario of degradation of the biome in the country, where forest remnants are embedded in an agricultural landscape, dominated by sugar cane fields and pasture fields. In this context, we aimed to investigate if natural forest regeneration responds differently to each agricultural matrix. Our hypothesis was that forest regeneration composition in remnants surrounded by sugar cane fields is different of forest regeneration composition in remnants surrounded by pasture fields, because these agricultural matrices impact differently forest biota. The present research was developed in Corumbataí river basin, in the countryside of São Paulo state. Shrub and tree individuals, from regeneration layer, were sampled in 60 plots 30x2 meters long (subdivided in plots 10x2 meters long) systematically distributed on the edges of 12 fragments. Firstly, we characterized the natural regeneration of the edges of forest remnants embedded in agricultural landscapes. Then we used the variables number of individuals.ha-1 (RN_HA), number of species/m2 (NESP_M2) and floristic diversity (ISHANNON) to analyze the differences in structure and composition of forest natural regeneration between sugar cane fields and pasture fields. These variables were used to analyze the statistical effects of conservation indicators, such as cattle entrance on forest remnants, abundance of woody-vines and grasses, and presence of eucalyptus trees on forest canopy, on natural regeneration. Floristic similarity between forest remnants was assessed by Jaccard Similarity Index. 5886 saplings were sampled among the 60 plots, divided in 57 families, 214 species and 31 morphospecies. Jaccard index indicated floristic similarity (45%) among the fragments inserted in sugar cane field and pasture field. Among the fragments inserted in pasture field, cattle entrance was the conservation indicator with the strongest interference over natural regeneration, decreasing both the number of plants per area and the floristic diversity. At sugar cane landscape, presence of eucalyptus on forest canopy increased the number of individuals per area. Grass and woody-vines abundance and presence of epiphytes were not significant for any variable, when analyzed with matrix type or fragment size. Among the subplots of 10m long, there was no variation of structure and composition of natural regeneration, what indicates that, in relation to floristic, diversity and sucessional classification, the regenerant vegetation is homogeneous in the first 30 meters of the edge. The results indicate that, even embedded in anthropogenic agricultural landscapes, the remnants studied still retain high floristic diversity. Natural regeneration has shown to be a good indicator of actual and future quality of forest remnants, and, together with conservation indicators, demonstrated that the fragments studied are subject to management actions, which may improve the role of biodiversity conservancy developed by natural regeneration
47

Environmental management reform through the Watershed Approach: A multi-case study of state agency implementation

Mawhorter, Julie H 01 August 2010 (has links)
In the past two decades, there has been a growing consensus regarding the inadequacies of the existing environmental policy regime and the need for reform to address complex, cross-jurisdictional sustainability challenges, such as nonpoint source pollution. Reform theory has focused on the need for more integrated, collaborative, adaptive, and results-oriented environmental management, while empirical studies have highlighted the wide implementation gap due to an array of institutional obstacles. Key principles and challenges of these four reform dimensions were synthesized in this study and used to assess implementation of the watershed approach by the U.S. Environmental Protection Agency and states since the early 1990s. This dissertation used a qualitative multiple case study design to examine the evolving watershed reform strategies of North Carolina, Georgia, and Kentucky, drawing on extensive document review and interviews with over 50 agency managers. Using an environmental federalism framework adapted from Scheberle (2004), the study explored the role of the national and regional EPA policy context, as well as state-level factors, in helping to shape the watershed approach strategies in the state cases. The research revealed that while EPA provided important initial support of state watershed management, its fragmented, output-driven program management continues to be a barrier to reform. EPA Region 4’s recent reform efforts demonstrate that regional offices can take critical steps to incorporate the watershed approach into internal agency management processes and external relations with states and stakeholders, but these changes often go against the grain of agency culture and norms. State agencies have made progress but face similar reform challenges, and their strategies are further shaped by important policy drivers, constraints, and resource limitations at the state level. More substantial investment is needed by EPA and states to: strengthen internal and external watershed coordination roles and forums; support collaborative stakeholder initiatives more fully where needed; and manage adaptively and accountably towards collectively defined watershed outcome targets.
48

Sustainable utilisation of Table Mountain Group aquifers

Duah, Anthony A. January 2010 (has links)
<p>The Table Mountain Group (TMG) Formation is the lowest member of the Cape Supergroup which consists of sediments deposited from early Ordovician to early Carboniferous times, approximately between 500 and 340 million years ago. The Table Mountain Group (TMG) aquifer system is&nbsp / exposed along the west and south coasts of South Africa. It is a regional fractured rock aquifer that has become a major source of bulk water supply to&nbsp / meet the agricultural and urban water requirements of the Western and Eastern Cape Provinces of South Africa. The TMG aquifer system comprises of an approximately 4000 m thick sequence of quartz arenite and minor shale layers deposited in a shallow, but extensive, predominantly eastwest striking&nbsp / asin, changing to a northwest orientation at the west coast. The medium to coarse grain size and relative purity of some of the quartz arenites,&nbsp / together with their well indurated nature and fracturing due to folding and faulting in the fold belt, enhance both the quality of the groundwater and its&nbsp / exploitation potential for agricultural and domestic water supply purposes and its hot springs for recreation. The region is also home to some unique&nbsp / and indigenous floral species (fynbos) of worldwide importance. These and other groundwater dependent vegetation are found on the series of&nbsp / mountains, mountain slopes and valleys in the Cape Peninsula. The hydrogeology of the TMG consists of intermontane and coastal domains which&nbsp / have different properties but are interconnected. The former is characterized by direct recharge from rain and snow melt, deep groundwater circulation with hot springs and low conductivity groundwater. The coastal domain is characterized by shallow groundwater occurrence usually with moderate to&nbsp / poor quality, indirect recharge from rainfall of shallow circulation and where springs occur they are usually cold. The sustainable utilization of the TMG&nbsp / aquifer addressed the issues of the groundwater flow dynamics, recharge and discharge to and from the aquifer / challenges of climate change and climate variability and their potential impact on the aquifer system. The concept of safe yield, recharge and the capture principle and the integration of&nbsp / sustainable yield provided the basis for sustainable utilization with the adaptive management approach. Methodology used included the evaluation of&nbsp / recharge methods and estimates in the TMG aquifer and a GIS based water balance recharge estimation. The evaluation of natural discharges and&nbsp / artificial abstractions from the TMG aquifer system as well as its potential for future development. The Mann-Kendal trend analysis was used to test historical and present records of temperature and rainfall for significant trends as indication for climate variability and change. The determination of&nbsp / variability index of rainfall and standard precipitation index were additional analyses to investigate variability. The use of a case study from the Klein&nbsp / (Little) Karoo Rural Water Supply Scheme (KKRWSS) within the TMG study area was a test case to assess the sustainable utilization of TMG aquifers.&nbsp / Results show that recharge varies in time and space between 1% and 55% of MAP as a result of different hydrostratigraphic units of the TMG based on&nbsp / geology, hydrology, climate, soil, vegetation and landuse patterns however, the average recharge is from 1% to 5% of MAP. The TMG receives recharge&nbsp / mainly through its 37,000 km2 of outcrop largely exposed on mountainous terrain. Natural discharges from the TMG include 11 thermal and numerous&nbsp / cold spring discharges, baseflow to streams and reservoirs, and seepage to the ocean. Results from this study also show increasing temperature&nbsp / trend over the years while rainfall trend generally&nbsp / remain unchanged in the study area. Rainfall variability persists hence the potential for floodsand droughts in the region remain. Global and Regional Models predict about 10% to 25% reduction in rainfall and increase in variability in future. Impacts of&nbsp / his change in climate will affect the different types of aquifers in various ways. Increase in temperature and reduction in rainfall will increase&nbsp / evapotranspiration, reduce surface flows and eventually reduce shallow aquifer resources. Coastal aquifers risk upsurge in salinisation from sea level&nbsp / rise and increase in abstractions from dwindling surface water resources. While floods increase the risk of contamination to shallow aquifers droughts&nbsp / put pressure on all aquifers especially deep aquifers which are considered to be more reliable due to the fact that they are far removed from surface conditions. Future population growth and increase in freshwater demand will put more pressure on groundwater. Recharge to groundwater have been&nbsp / over-estimated in certain areas in the past leading to high abstraction rates from boreholes causing extensive groundwater storage depletion evident by high decline in groundwater levels in these areas and hampering sustainable management of the aquifer resources. Over-abstraction have resulted in&nbsp / loss of stream flow and baseflow reduction to streams during summer, complete loss of springs and reduction of flow to others. Flow to wetlands,&nbsp / riparian vegetation, and sometimes loss and shifts in dependent ecosystems have also resulted from over-abstraction. Sustainability has spatial and&nbsp / temporal implications due to changing climate and demand. The study recommends adaptive management practices in which several factors are&nbsp / considered in managing groundwater together with surface water resources in order to maintain ecological and environmental integrity. The KKRWSS&nbsp / and other groundwater supply schemes in the Western and Eastern Cape Provinces demonstrate the huge potential of the TMG to provide freshwatersupply for domestic and irrigation water needs however, the huge decline in groundwater levels due to over-abstraction in the KKRWSS and&nbsp / other groundwater schemes underscores the need for sustainable utilization of the TMG groundwater resources for present and future generations with&nbsp / minimal impacts on the quality, dependent hydrological and ecosystems as well as the environment.</p>
49

Sustainable utilisation of Table Mountain Group aquifers

Duah, Anthony A. January 2010 (has links)
<p>The Table Mountain Group (TMG) Formation is the lowest member of the Cape Supergroup which consists of sediments deposited from early Ordovician to early Carboniferous times, approximately between 500 and 340 million years ago. The Table Mountain Group (TMG) aquifer system is&nbsp / exposed along the west and south coasts of South Africa. It is a regional fractured rock aquifer that has become a major source of bulk water supply to&nbsp / meet the agricultural and urban water requirements of the Western and Eastern Cape Provinces of South Africa. The TMG aquifer system comprises of an approximately 4000 m thick sequence of quartz arenite and minor shale layers deposited in a shallow, but extensive, predominantly eastwest striking&nbsp / asin, changing to a northwest orientation at the west coast. The medium to coarse grain size and relative purity of some of the quartz arenites,&nbsp / together with their well indurated nature and fracturing due to folding and faulting in the fold belt, enhance both the quality of the groundwater and its&nbsp / exploitation potential for agricultural and domestic water supply purposes and its hot springs for recreation. The region is also home to some unique&nbsp / and indigenous floral species (fynbos) of worldwide importance. These and other groundwater dependent vegetation are found on the series of&nbsp / mountains, mountain slopes and valleys in the Cape Peninsula. The hydrogeology of the TMG consists of intermontane and coastal domains which&nbsp / have different properties but are interconnected. The former is characterized by direct recharge from rain and snow melt, deep groundwater circulation with hot springs and low conductivity groundwater. The coastal domain is characterized by shallow groundwater occurrence usually with moderate to&nbsp / poor quality, indirect recharge from rainfall of shallow circulation and where springs occur they are usually cold. The sustainable utilization of the TMG&nbsp / aquifer addressed the issues of the groundwater flow dynamics, recharge and discharge to and from the aquifer / challenges of climate change and climate variability and their potential impact on the aquifer system. The concept of safe yield, recharge and the capture principle and the integration of&nbsp / sustainable yield provided the basis for sustainable utilization with the adaptive management approach. Methodology used included the evaluation of&nbsp / recharge methods and estimates in the TMG aquifer and a GIS based water balance recharge estimation. The evaluation of natural discharges and&nbsp / artificial abstractions from the TMG aquifer system as well as its potential for future development. The Mann-Kendal trend analysis was used to test historical and present records of temperature and rainfall for significant trends as indication for climate variability and change. The determination of&nbsp / variability index of rainfall and standard precipitation index were additional analyses to investigate variability. The use of a case study from the Klein&nbsp / (Little) Karoo Rural Water Supply Scheme (KKRWSS) within the TMG study area was a test case to assess the sustainable utilization of TMG aquifers.&nbsp / Results show that recharge varies in time and space between 1% and 55% of MAP as a result of different hydrostratigraphic units of the TMG based on&nbsp / geology, hydrology, climate, soil, vegetation and landuse patterns however, the average recharge is from 1% to 5% of MAP. The TMG receives recharge&nbsp / mainly through its 37,000 km2 of outcrop largely exposed on mountainous terrain. Natural discharges from the TMG include 11 thermal and numerous&nbsp / cold spring discharges, baseflow to streams and reservoirs, and seepage to the ocean. Results from this study also show increasing temperature&nbsp / trend over the years while rainfall trend generally&nbsp / remain unchanged in the study area. Rainfall variability persists hence the potential for floodsand droughts in the region remain. Global and Regional Models predict about 10% to 25% reduction in rainfall and increase in variability in future. Impacts of&nbsp / his change in climate will affect the different types of aquifers in various ways. Increase in temperature and reduction in rainfall will increase&nbsp / evapotranspiration, reduce surface flows and eventually reduce shallow aquifer resources. Coastal aquifers risk upsurge in salinisation from sea level&nbsp / rise and increase in abstractions from dwindling surface water resources. While floods increase the risk of contamination to shallow aquifers droughts&nbsp / put pressure on all aquifers especially deep aquifers which are considered to be more reliable due to the fact that they are far removed from surface conditions. Future population growth and increase in freshwater demand will put more pressure on groundwater. Recharge to groundwater have been&nbsp / over-estimated in certain areas in the past leading to high abstraction rates from boreholes causing extensive groundwater storage depletion evident by high decline in groundwater levels in these areas and hampering sustainable management of the aquifer resources. Over-abstraction have resulted in&nbsp / loss of stream flow and baseflow reduction to streams during summer, complete loss of springs and reduction of flow to others. Flow to wetlands,&nbsp / riparian vegetation, and sometimes loss and shifts in dependent ecosystems have also resulted from over-abstraction. Sustainability has spatial and&nbsp / temporal implications due to changing climate and demand. The study recommends adaptive management practices in which several factors are&nbsp / considered in managing groundwater together with surface water resources in order to maintain ecological and environmental integrity. The KKRWSS&nbsp / and other groundwater supply schemes in the Western and Eastern Cape Provinces demonstrate the huge potential of the TMG to provide freshwatersupply for domestic and irrigation water needs however, the huge decline in groundwater levels due to over-abstraction in the KKRWSS and&nbsp / other groundwater schemes underscores the need for sustainable utilization of the TMG groundwater resources for present and future generations with&nbsp / minimal impacts on the quality, dependent hydrological and ecosystems as well as the environment.</p>
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[en] MONITORING AND EVALUATING THE PERFORMANCE OF SCIENCE AND TECHNOLOGY PARKS: PROPOSAL OF A CONCEPTUAL ADAPTIVE MODEL / [pt] MONITORAMENTO E AVALIAÇÃO DE DESEMPENHO DE PARQUES TECNOLÓGICOS: PROPOSIÇÃO DE UM MODELO CONCEITUAL ADAPTATIVO

RAFAEL MAGALHAES LYRA 21 February 2018 (has links)
[pt] Destaca-se como um dos principais desafios da gestão de parques tecnológicos a criação de modelos e ferramentas de monitoramento e avaliação de desempenho, que considerem a diversidade de perfis estratégicos e de modelos de negócios desses ambientes de inovação. Na perspectiva de contribuir para o aprimoramento do processo de monitoramento e avaliação de desempenho de parques tecnológicos no Brasil e no exterior, o objetivo da dissertação é desenvolver e aplicar um modelo conceitual para o referido processo, baseado na abordagem de gestão adaptativa, que permita aos gestores definir indicadores e métricas em função de perfis estratégicos e modelos de negócios comuns a determinados agrupamentos de parques. A pesquisa pode ser considerada descritiva, metodológica e aplicada. A partir dos resultados da revisão bibliográfica e documental sobre os temas centrais da pesquisa, desenvolveu-se um modelo conceitual adaptativo para monitoramento e avaliação de desempenho de parques tecnológicos. Visando demonstrar a aplicabilidade desse modelo no contexto de diferentes parques tecnológicos no Brasil e explicitar seus diferenciais metodológicos em comparação a outros modelos reportados na literatura especializada, realizou-se um estudo empírico focalizando a fase de planejamento do modelo junto a 26 participantes do 1º Curso para Gestores de Parques e Ambientes de Inovação, oferecido pela Uni-Anprotec, em parceria com o Instituto Gênesis, da PUC-Rio, em 2016. Destacam-se como principais contribuições da pesquisa um modelo conceitual adaptativo para mensuração e avaliação de desempenho de parques tecnológicos e conjuntos de indicadores e métricas associados a diferentes tipos de parques. / [en] One of the main challenges of managing science and technology parks is the creation of models and tools for monitoring and evaluating their performance, which consider the diversity of strategic profiles and business models of these innovation environments. Aiming to contribute to the improvement of the process of monitoring and evaluating the performance of science and technological parks in Brazil and abroad, the objective of this dissertation is to develop and apply a conceptual model for this process, based on adaptive management approach, which allows managers to establish indicators and metrics according to strategic profiles and business models common to certain groupings of parks. This research can be considered descriptive, methodological and applied. Based on the results provided by the bibliographic and documentary review on the central themes of the research, a conceptual adaptive model for monitoring and evaluating the performance of technology parks was developed. Aiming to demonstrate the applicability of this model in the context of different science and technology parks in Brazil and to explain its methodological differentials compared to other models reported in the specialized literature, an empirical study, focusing on the planning phase of the model, was carried out during 2016 with 26 participants of the 1st Course for Managers of Parks and Environments of Innovation, offered by Uni-Anprotec in partnership with Instituto Gênesis. The main contributions of the research are a flexible model for measuring and evaluating the performance of technological parks and sets of indicators and metrics associated with different types of parks.

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