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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.
21

Uso de subprodutos de milho, soja e trigo como adsorvente de ferro e manganês em sistema aquoso / Use of by-products corn stover, soybean and wheat as iron and manganese sorbent in an aqueous system

Furlan, Fernanda Lansa 20 April 2017 (has links)
Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná / O aumento do volume de subprodutos agrícolas gerados acompanhado do descarte inadequado desses é um problema mundial crescente. O aproveitamento desses subprodutos agrícolas é de extrema importância, já que resulta na redução dos impactos ambientais, preservação da saúde da população, permitindo agregar valor a esses materiais suprindo as necessidades econômicas e globais. Uma das formas de aproveitamento está relacionada à capacidade de alguns desses subprodutos agrícolas na remoção eficiente de micro-contaminantes em sistemas aquosos devido às suas propriedades adsorventes. O processo de adsorção é um método que promove a remoção de micro-contaminantes em soluções aquosas. Este trabalho teve como objetivo investigar o uso dos subprodutos agrícolas: palha de milho (PM), palha de trigo (PT), palha de soja (PS) e casca de soja (CS) para produção de diferentes adsorventes para remover Fe e Mn. Para cada subproduto investigado, foram utilizados dois diferentes adsorventes: natural (celulose/lignina) e um modificado com EDTA (ácido etilenodiaminotetraacético). Após a caracterização dos adsorventes por FTIR (espectroscopia de infravermelho por transformada de Fourier), teor de nitrogênio, procedeu-se com os ensaios de adsorção para avaliar a eficiência e análise elementar desses adsorventes em soluções aquosas de Fe e Mn. A concentração dos micro-contaminantes na solução foi determinada por espectrofotometria de absorção atômica. Em seguida, para os adsorventes natural e modificado mais eficientes, aplicou-se os modelos cinéticos de pseudo-primeira-ordem e pseudo-segunda-ordem para definir a ordem da reação de adsorção. Os resultados obtidos indicaram que o adsorvente modificado obtido da casca de soja (CSE) apresentou os melhores resultados na adsorção de Fe (96%) e Mn (88%) em solução aquosa. O modelo de pseudo-segunda ordem apresentou melhor ajuste da reação de adsorção para ambos os micro-contaminantes investigados. De modo geral, a casca de soja modificada mostrou ser um adsorvente adequado para a remoção do ferro e manganês, pois apresentou alta eficiência, como avaliado neste estudo. / The increased volume of agricultural by-products generated coupled with inadequate disposal of these is a growing worldwide problem. The use of these agricultural by-products is of extreme importance, since it results in the reduction of environmental impacts, preservation of the health of the population, allowing adding value to these materials supplying the economic and global needs. One of the ways of exploitation is related to the ability of some of these agricultural by-products to efficiently remove micro-contaminants in aqueous systems due to their adsorbent properties. The adsorption process is a method that promotes the removal of micro-contaminants in aqueous solutions. This work aimed to investigate the use of agricultural by - products: corn straw (PM), wheat straw (PT), soybean straw (PS) and soybean husk (CS) to produce different adsorbents to remove Fe and Mn. For each by-product investigated, two different adsorbents were used: natural (cellulose / lignin) and one modified with EDTA (ethylenediaminetetraacetic acid). After the characterization of the adsorbents by FTIR (Fourier transform infrared spectroscopy), nitrogen content, the adsorption tests were carried out to evaluate the efficiency and elemental analysis of these adsorbents in aqueous solutions of Fe and Mn. The concentration of the micro-contaminants in the solution was determined by atomic absorption spectrophotometry. Then, for the most efficient natural and modified adsorbents, the kinetic models of pseudo-first order and pseudo-second order were applied to define the order of the adsorption reaction. The results showed that the modified adsorbent obtained from the soybean hull (CSE) showed the best results in the adsorption of Fe (96%) and Mn (88%) in aqueous solution. The pseudo-second order model showed a better adjustment of the adsorption reaction for both micro-contaminants investigated. In general, the modified soybean hull proved to be an adequate adsorbent for the removal of iron and manganese, since it presented high efficiency, as evaluated in this study.
22

Valoração dos serviços ecossistemicos em bacias hidrograficas / Valuation of ecosystem services in watersheds

Cunha, Flavio Luiz Silva Jorge da 12 August 2018 (has links)
Orientador: João Fernando Marques / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Economia / Made available in DSpace on 2018-08-12T16:37:30Z (GMT). No. of bitstreams: 1 Cunha_FlavioLuizSilvaJorgeda_D.pdf: 2237333 bytes, checksum: dc053a7f7e28160941411e0d61ca0e51 (MD5) Previous issue date: 2008 / Resumo: Este trabalho objetiva apresentar e discutir a valoração de serviços ecossistêmicos, a partir do conceito de funções e serviços ecossistêmicos e da aplicação dos métodos de valoração econômica em uma bacia hidrográfica devido a ocupação pela agricultura. Mostra que a valoração é um dentre outros importantes instrumentos a serem mobilizados para a preservação ambiental e para o reconhecimento e aceitação social da necessidade da gestão dos ambientes naturais, tendo como orientação a utilização sustentável dos recursos. Assim, o trabalho pautou-se por apresentar as possibilidades teóricas a partir das visões tradicionais e da economia ecológica, apresentou-se um ambiente antropizado e suas características sempre procurando destacar as questões da ocupação e dos impactos ambientais. Além da caracterização da ocupação do espaço e das determinantes sócio-econômicas foi realizado um estudo na bacia hidrográfica dos rios Mogi-Guaçu, Pardo e Baixo Grande, doravante denominada bacia do Mogi - Pardo, no Estado de São Paulo, com o objetivo de determinar a Disposição a Pagar por água limpa junto à população dos municípios que fazem parte da bacia. A partir das recomendações do Relatório da National Oceanic and Atmospheric Administrations (NOAA), o estudo mostra que mesmo com suas limitações, o método de valoração contingente (MVC) pode contribuir com uma medida de valor para auxiliar no processo de tomada de decisão. / Abstract: This study aims to present and discuss the valuation of ecosystem services, from the concept of ecosystem functions and services and the application of methods of economic valuation in a watershed because the occupation by agriculture. To show that the valuation is one among other important tools being mobilized for environmental preservation and recognition and social acceptance of the need for management of natural environments, with a guide to sustainable resource use. Thus, the work is guided by presenting the theoretical possibilities from the visions of traditional and ecological economy, proved to be an anthropic environment and its features always looking to highlight the issues of occupation and environmental impacts. In addition to the characterization of the occupation of space and determinants of socio-economic study was conducted in the watershed of rivers Mogi-Guaçu, Pardo and Grande, in the state of Sao Paulo, aiming to determine Willingness to pay for the clean water from the population of municipalities that are part of the basin. Based on the recommendations of the Report of the National Oceanic and Atmospheric Administrations (NOAA), the study shows that even with its limitations, the contingent valuation method (MVC) can provide a measure of value to assist in the decision-making process. / Doutorado / Desenvolvimento Economico, Espaço e Meio Ambiente / Doutor em Desenvolvimento Economico
23

Utilização do conceito de fugacidade na previsão do comportamento ambiental do carbosulfan e do carbofuran na cultura do arroz irrigado

Plese, Luis Pedro de Melo 24 February 2005 (has links)
Orientador: Luiz Lonardoni Foloni / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-04T06:05:15Z (GMT). No. of bitstreams: 1 Plese_LuisPedrodeMelo_D.pdf: 1119151 bytes, checksum: 71b0dc99bac0c1f913f9f77bc3014bc4 (MD5) Previous issue date: 2005 / Resumo: A utilização de produtos fitossanitários para o controle de plantas daninhas, pragas ou doenças têm sido muito difundido em função da necessidade crescente da oferta de alimentos, limitação de áreas agricultáveis e disponibilidade de mão-de-obra. Os problemas gerados com a aplicação de produtos fitossanitários, sem o devido conhecimento, podem causar riscos ao meio ambiente e à saúde humana. A tendencia é órgão fiscalizador é exigir que antes do lançamento de um novo produto no mercado e antes de sua aplicação em áreas agricultáveis seja feito estudo rigoroso de seu comportamento no meio ambiente. Quando existe um bom banco de dados, modelos matemáticos são desenvolvidos objetivando prever comportamento ambiental do produto fitossanitário. O conceito de fugacidade, embora não seja novo, praticamente não tem sido estudado no Brasil na áreadas ciencias agrárias. A fugacidade pode ser um novo caminho para quantificar o transporte, a biocumulação e transferência entre os compartimentos ambientais. Este trabalho teve por objetivos: (a) desenvolver uma metodologia preliminar de previsão de destino ambiental dos inseticidas carbosulfan e carbofuran no cultivo de arroz irrigado, através de modelo matemático baseado no conceito de fugacidade, para delimitar os compartimentos mais vulneráveis; (b) prever o comportamento e o destino ambiental das moléculas do carbosulfan e carbofuran no cultivo de arroz irrigado, aplicando o conceito de fugacidade; (c) verificar, em condições de campo, o comportamento e o destino ambiental do carbosulfan e do carbofuran, comparando-os com a previsão feita. A fase experimental foi desenvolvida na Fazenda Varjão, município de Bariri-SP, coordenadas (21º59'47¿S e 48º36'41¿LGr) em solo Gleissolos. A cultura foi implantada no dia 22/11/02, utilizando-se a cultivar IRGA-420. Para evitar possíveis contaminações, a área experimental foi locada em um tabuleiro de 2 ha a montante da propriedade. A propriedade foi dividida em tabuleiro com dimensões variáveis de 1,5 a 2,5 ha, totalizando 200 tabuleiros, separados por canais de irrigação e drenagem. Tradicionalmente, para o controle da larva da bicheira-da-raiz é recomendado o uso do inseticida carbosulfan, na dose de 400 g i.a. ha-1, no sistema de benzedura. Foram determinados 8 pontos ao acaso no tabuleiro estudado, para coleta de amostras. Os compartimentos amostrados foram água laminar, solução do solo e do próprio solo. As seqüências de tempo escolhidas para as coletas de amostras de água laminar e solução do solo foram de 0, 24, 48, 96, 192, 378 e 678 horas após a aplicação. As amostras de solo foram realizadas em 0, 24, 48, 96, 192, 378, 678, 1536 e 1656 horas após a aplicação. As cinéticas de degradação do carbofuran e do carbosulfan foram avaliadas em condições de campo através da análise dos resíduos das amostras coletadas. Utilizou-se da identificação e quantificação dos resíduos foi realizada através de um detector seletivo de massas, acoplado ao cromatógrafo. Este foi operado no modo de monitoramento de íons (SIM), sendo utilizados os fragmentos 160 e 164 para a quantificação de carbofuran e carbosulfan, respectivamente. Os dados experimentais e as equações diferenciais que descrevem a cinética do carbosulfan e do carbofuran permitiram estimar a meia-vida dos inseticidas na água e na solução do solo e no próprio solo. Os valores estimados das meias-vidas para o carbosulfan na água laminar, no solo e na solução do solo foram 1, 25 e 21 dias, respectivamente. Para o carbofuran as meias-vidas na água laminar e na solução do solo foram 3 e 10 dias, respectivamente. Os resultados indicam os compartimentos preferenciais do carbofuran, facilitando a tarefa de amostragens em programas do monitoramento da qualidade ambiental, e permite antecipar o destino ambiental do inseticida carbofuran. Experimentos de campo foram conduzidos para verificar a proximidade entre os valores simulados e os valores observados de concentrações do carbofuran na água e no solo / Abstract: Pesticide use to control pests, diseases and weeds is steadily increasing due to a general food demand increase, cropping area limitation, and manpower availability. Pesticide application without a sound knowledge may hazard environment and human health. Regulatory agencies enforces that, before a new product releasing to the market for agricultural use, intensive studies on its environment impacts ought to be developed. When a large and useful database is available, mathematical models are developed to estimate or predict product environmental behavior. In Brazil, although the available knowledge, practically there are no studies on fugacity concept applied to agricultural subjects. Fugacity in the proposed form might be a new tool in quantifying the movement, bioaccumulation and transfer of pesticides betweeen environment compartments. The objectives of this research work were: (a) to develop a preliminary method for predicting the environmental destination of carbosulfan and carbofuran insecticides applied to field irrigated rice, using a model based on the fugacity concept to delimit most vulnerable compartments; (b) to predict the behavior and environmental destination of carbosulfan and carbofuran molecules applied on field irrigated rice, using the fugacity concept; (c) to validate the prediction model by comparison with experimental data obtained under field conditions. The experimental data was obtained from a field irrigated rice experiment carried out at 'Varjão¿ Farm, district of Bariri, State of São Paulo, Brazil (21º59'47¿S and 48º36'41¿LGr) in a Gleissol type soil. Rice cv IRGA-420 was seeded in 11.22.2004, using the uppermost rice field area to avoid eventual contaminations. The property is divided in 1.5-2.5 ha-field areas, separated by rrigation or drainage channels. Traditionally, rice root weevil is controlled through carbosulfan application at the rate of 400 g a.i. ha-1. Eight sampling points were randomly located in the rice fields. The sampled compartments were: laminar water, soil solution and soil. The time sequence for water and soil solution samplings were 0, 24, 48, 96, 192, 378 and 678 hours after pesticide application, and for soil, 0, 24, 48, 96, 192, 378, 678, 1536 and 1656 hours after pesticide application. The carbofuran and carbosulfan degradation kinetics were evaluated through residue sample analysis. Residue identification and quantification were made through a mass selective detector (MSD) device coupled to a chromatograph. This equipment was operated in the system of ion monitoring mode (SIM), utilizing 160 and 164 fragments for the carbofuran and carbosulfan quantification, respectively. The experimental data and differential equations that describe the carbofuran and carbosulfan kinetics in the field rice water, allowed the insecticide half-life estimation in the three compartments: water, soil solution and soil. The estimated values for carbosulfan half-lives were: 1, 25 and 21 for water, soil and soil solution, respectively, and 3 and 10 days for carbofuran half-lives for the water and soil solution, respectively. The proposed model showed to be viable for the evaluation of insecticide behavior inthe irrigated field rice. High correlation was observed between data obtained by simulation and that from field experimentation, through residue analyses in the water and soil compartments. In an evaluation of environmental risks, the fugacity model level IV was adequate to estimate or predict the insecticide product destination / Doutorado / Agua e Solo / Doutor em Engenharia Agrícola
24

Space matters: Quantifying ecosystem-mediated externalities

Missirian, Anouch January 2020 (has links)
Economic and ecological processes interact with one another over both spatial and temporal dimensions.This dissertation explores four socio-ecological systems where space crucially matters for both economic and ecological outcomes. In the first chapter, a windborne chemical dictates the diffusion in space of a new agricultural technology. The second chapter dissects the notion of landscape complexity to find which of its components matter for the intensity of insect pressure in agriculture, and thus the use of insecticides. In the third chapter, the location of participants in an environmental program seeking to curb deforestation points to additionality problems and anticipates the lack of measurable effects of the program. Knowing where crops are grown and temperatures less well-suited for their thriving is key to identifying in chapter four the effects of weather fluctuations on asylum applications into the European Union. The spatial dimension tends to be hard to apprehend and overlooked, but those four pieces together stress that space matters in the study of sustainable development.
25

Prediction and ecotoxicological effects of runoff induced pesticide contamination in agricultural surface waters : a risk assessment using GIS and microcosms

Dabrowski, James Michael 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Runoff is generally regarded as one of the most important routes of nonpoint source pesticide pollution in agricultural surface waters. Of major concern is the fact that low, sub-lethal levels of pesticide exposure are responsible for negative ecotoxicological effects, stressing the need for methods capable of identifying problem areas where populations could be at risk. Predicted average losses of three pesticides in tributaries of nine sub-catchments of the Lourens River were calculated through use of a GIS-based runoff model. There was a significant (p < 0.005) positive correlation between the predicted average loss and mean measured concentrations of the insecticides both in water and suspended sediments (R2 between 0.75 and 0.9), indicating that the model could serve as a powerful tool for the risk assessment and management of surface waters in South African orchard areas. Based on field relevant exposure scenanos, the potential effects of azinphos-methyl on macroinvertebrate communities were evaluated in a combined microcosm and field approach. Microcosms were contaminated for 1 h with AZP (control, 0.2; 1,5and 20 ug/L; three replicates each) and acute effects on survival were evaluated 6 days after exposure. The sensitivity or tolerance of 12 core taxa was determined based on their response to the exposure scenarios and compared to field tolerance/sensitivity as was established by a field investigation at a control and contaminated site of the Lourens River. The sensitivity/tolerance of ten of the 12 taxa corresponded to that which was found in the field. Thus microcosm studies employing a field relevant design can be successfully linked to field studies and indicate that transient pesticide contamination affects the aquatic communities of the Lourens River. / AFRIKAANSE OPSOMMING Afloop word oor die algemeen beskou as een van die belangrikste roetes van niepuntbron pestisiedbesoedeling in landbou oppervlakwaters. Die feit dat lae, sub-letale vlakke van pestisiedblootstelling negatiewe ektoksikologiese gevolge kan hê, is van groot belang. Dit beklemtoon die behoefte aan metodes om probleemgebiede te kan identifiseer waar bevolkings aan risiko onderhewig is. 'n GIS-gebaseerde afloopmodel is gebruik om die gemidddelde verlies van drie pestisiede in die sytakke van nege sub-opvangsgebiede van die Lourensrivier te voorspel. Daar was 'n beduidende (p < 0.005) positiewe korrelasie tussen die voorspelde gemiddelde verlies en gemete konsentrasies van insektisiede in beide die water en sediment (R2 between 0.75 and 0.9) fases, wat aandui dat die model as 'n kragtige hulpmiddel vir risikobestuur van oppervlakwaters in Suid Afrikaanse boord-gebiede kan dien. Die potensiële gevolge van azinfos-rnetiel (AZP) op makroinvertebraat gemeenskappe is deur middel van 'n gekombineerde mikrokosmos (wat op veldrelevante blootstellings gebaseer is) en veldbenadering bepaal. Mikrokosmosse is vir 1 h met AZP gekontamineer (kontrole; 1; 0.2; 1; 5 en 20 ~g1L; drie replikate elk), en die akute gevolge op oorlewing is ge-evalueer na ses dae van blootstelling. Die sensitiwiteit of toleransie van 12 sleutel taksa is deur middel van hulle respons op die blootstellingsreeks bepaal, en met hulle veldtoleransie/sensitiwiteit vergelyk wat in 'n veldstudie by 'n kontrole- en gekontamineerde gebied in die Lourensrivier bepaal is. Die sensitiwiteit/toleransie van 10 van die 12 taksa in die mikrokosmos eksperimente het ooreengestem met die wat in die veld gevind is. Mikrokosmosstudies wat op 'n veldrelevante ontwerp gebaseer is, kan dus suksesvol aan veldstudies gekoppel word, en dui aan dat oorgedraagde pestisiedkontaminasie die akwatiese gemeenskap van die Lourensrivier beinvloed.
26

An investigation into the effectiveness of corporate sustainability programmes and initiatives in the agricultural sector : the case of British American Tobacco Zimbabwe

Nyanyirai, Stanley 03 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: In recent years, a great deal of attention has been paid towards the notion of corporate sustainability, which has variously been defined as meaning the incorporation of social, environmental, economic, and cultural concerns into corporate strategy and bottom line. The preliminary investigation suggests that Multi-National Corporations (MNCs) are mainly worried about securing permission for commencing operations and not about the wellbeing of locals and their livelihoods. Further to this, one of the main reasons why efforts aimed at improving sustainability are not yielding significant and lasting results, is that solution seekers in business, science, government and the research community are still operating in the same old paradigm of using basically the same tools and adopting the same world view that threaten sustainability in the first. The key and clear research objectives of this study are:- to ascertain if there is a link between British American Tobacco Zimbabwe (BATZ) top management philosophy, corporate strategy and the company`s corporate sustainability programmes, initiatives and other efforts, and the various stakeholders, and, if so, how these are communicated to them; to establish the degree of integrating sustainable development practice and initiatives into the BATZ business model in order to have long term benefits for both the company and its various stakeholders - these are an integral part of the socio-ecological system, and will help the business understand the resilience of the system and where in the system they should operate; to establish the depth, scope and culture of sustainability in terms of the extent to which they inserted inside (embedded) the BATZ operations; and to ascertain the level of economic, social and environmental effects of BATZ`s corporate sustainability programmes and initiatives in the locality in which it operates. The research used focus group and key informant discussions, one-on-one interviews, and to a limited extent a semi-structured research questionnaire. Information was also accessed from company internal information management portals, and BATZ’s group sustainability and other reports. The conclusion was that renewable energy programmes at BATZ were driven by energy insecurity and scarcity. Currently BATZ is not recycling water used in cigarette manufacturing operations, waste recycling of cut-rag tobacco has been occurring, and BATZ will continue to provide agronomic support to small scale farmers under its Social Responsibility in Tobacco Programmes (SRTP) towards leaf sustainability. The Rocket Barn concept is one of the most innovative intermediate technological breakthroughs meant for improving wood fuel efficiency in tobacco curing. Socially BATZ has done some good works in addressing some of society’s key challenges. There have been benefits for key corporate stakeholders in having BATZ operating in Zimbabwe. The research will assist BATZ to fully understand the socio-ecological system in which it operates; a fundamental understanding to improve corporate sustainability, which will then require a shift in sustainability-oriented efforts. / AFRIKAANSE OPSOMMING: Die idee van korporatiewe volhoubaarheid het die afgelope klompie jare baie aandag geniet. Wyd gesien, kom definisies neer op die insluiting van maatskaplike, omgewings-, ekonomiese en kulturele ondernemings in basiese korporatiewe strategieë. Die voorlopige ondersoek stel voor dat MNK’s wel gemoeid is met die verkryging van toestemming om bedrywe te stig, maar nie juis die welsyn en dag-tot-dag-belange van die plaaslike gemeenskap op die hart dra nie. Volgens (Fiksel 2003) en Du Plessis (2008) is een van die hoofredes waarom pogings om volhoubaarheid te verbeter nog nie betekenisvolle en blywende resultate gelewer het nie, die feit dat die mense betrokke by sake-ondernemings, wetenskap, die regering en navorsing wat na oplossings soek, nog geen paradigmaskuif gemaak het wat hul denkpatrone betref nie. Hulle gebruik steeds dieselfde uitgediende gereedskap en huldig nog dieselfde wêreldsienings wat volhoubaarheid in die eerste plek bedreig het. (Fiksel, 2003, Du Plessis, 2008, Hayward et al 2010). Die doelwitte van die navorsing is: om uit te vind of daar ’n skakel is tussen die filosofie en korporatiewe strategie van BATZ-hoofbestuur en die maatskappy se volhoubaarheidsprogramme, inisiatiewe ens; om te bepaal in watter mate volhoubare ontwikkeling en volhoubaarheidspraktyke en inisiatiewe geïntegreer word in die BATZ-korporatiewe model, om impak vas te stel en die kultuur van volhoubaarheid binne BATZ-bedrywe te bepaal. Die navorsing het gebruik gemaak van fokusgroepe, van sleutelbesprekings deur ingeligte persone, een-tot-een-onderhoude en in enkele gevalle selfs van gestruktureerde vraelyste. Toegang tot inligting is ook verkry deur middel van ‘n maatskappy se interne inligtingsbestuursbronne, BAT-groep-volhoubaarheids- en ander verslae. Die gevolgtrekking is dat hernubare energieprogramme afgedwing is op Batz deur die onsekerheid oor en die gebrek aan energie. Tans word water wat in sigaretbedrywe gebruik word nie deur BATZ herwin nie, maar afval van “cut-rag” tabak word wel herwin, en BAT Zimbabwe sal voortgaan met agronomiese ondersteuning aan kleinskaalboere kragtens sy Maatskaplike Verantwoordelikheid t.o.v. Tabak Programme (MVTP) vir blaarvolhoubaarheid. Die “Rocket Barn-”konsep is een van die innoverendste intermediêre tegnologiese deurbrake om die effektiwiteit van houtbrandstof by die droogmaak van tabak te verbeter. Op maatskaplike vlak het BATZ Zimbabwe goeie werk gedoen deur enkele uitdagings van die gemeenskap die hoof te bied. Die feit dat BAT in Zimbabwe werksaam is, was tot voordeel van korporatiewe belangstellendes. Die navorsing sal BATZ help om die sosio-ekologiese stelsel waarvolgens dit bedryf word, ten volle te verstaan, en om korporatiewe volhoubaarheid te bevorder, wat dan ‘n kopskuif ten opsigte van volhoubaarheidsgeöriënteerde pogings sal vereis.
27

Contested spaces: NTFPS, livelihoods, and conservation planning

Unknown Date (has links)
This research examines tensions between Latino/a farmworkers, who rely on the seasonal harvest of saw palmetto (Serenoa repens [W. Bartram] Small) berries for increased livelihood security, and conservationists and land-managers who view harvesting as detrimental for wildlife. Informal harvesting occurs on public and private lands, sometimes without permission. Berries, though ubiquitous on the landscape, have become a contested resource. The rapid conversion of rural wildlife habitat into suburban development has increased State urgency to bring natural areas into protection along the Florida Ecological Greenways Network. Habitat infringement and associated pressures on wildlife by development has led to the promotion of the state-wide Florida Wildlife Corridor, based on the FEGN. This corridor would connect isolated Florida black bear (Ursus americanus floridanus) populations and Florida panthers (Puma concolor coryi) with other populations. The scale of the commercial berry industry is unknown, but is estimated at millions of pounds annually. State and wildlife conservationists are increasingly concerned with the perceived scale of the harvest and its possible associated effects on wildlife, particularly Florida black bears. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
28

Landbou en sy biofisiese omgewing : 'n GIS gebaseerde analise van die volhoubaarheid van landboupraktyke in die Piketbergse landdrosdistrik

Opperman, Daleen 03 1900 (has links)
Thesis (MA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Agriculture occupies 86 percent of land that is being utilised for the needs of a growing population in the Western Cape. This implies that there has to be certain impacts on the environment regarding the practices associated with different agricultural activities. Negative impacts pertain to soil degradation, water quality problems, loss of biodiversity and vegetation deterioration. It must also be taken into consideration that each land use within agriculture has a different interaction with the environment. The nature of land use and environment will therefore determine the most important issues influencing the extent of impact on the environment. Certain problem areas in the Western Cape have been identified as the result of conflict between agriculture and the environment. However, if agriculture is practiced and managed in a sustainable manner, it can be productive, while at the same time assuring a healthy environment. To achieve such a situation a protocol has to exist whereby sensitive areas, with regard to potential impact on the environment by agriculture, can be identified. Considering this, the most important concept of the study was to develop methodology appropriate for evaluating and identifying farming areas where current practices threaten the sustainable use of natural resources. The result is a model that aims to identify the different land uses and then evaluate each agricultural activity through a holistic approach with regard to impact on the environment. The Piketberg magisterial district was chosen as study region to put the methodology into practice. Datasets regarding soil types, climate, water quality, vegetation and agricultural practices, specific to the study area, were gathered. By using Geographical Information Systems, the datasets could be manipulated to derive the necessary information needed for running the model. This produced maps showing areas of low to high impact on the environment and indicating the specific landuse responsible for each impact. / AFRIKAANSE OPSOMMING: Landbou beslaan 86 persent van die grond in die Wes-Kaap wat aangewend word om te voorsien in die behoeftes van 'n groeiende bevolking. Praktyke verbonde aan die onderskeie landbouaktiwiteite het egter sekere impakte op die omgewing. Negatiewe impak hou verband met gronddegradasie, waterkwaliteitprobleme, verlies aan biodiversiteit en plantegroei agteruitgang. Elke landbougrondgebruik het ook 'n spesifieke interaksie met die omgewing. Die belangrikste bydraende faktore tot impak op die omgewing sal dus deur die aard van die grondgebruik en omgewingsensitiwiteit bepaal word. Sekere probleemareas is reeds in die Wes-Kaap geïdentifiseer weens negatiewe interaksie tussen landbou en die omgewing. Indien landbou egter volhoubaar beoefen en bestuur word, kan dit produktief wees en terselfdertyd 'n gesonde omgewing verseker. Die behoefte het ontstaan om 'n protokol binne landbou te vestig, waardeur daar gefokus word op die uitwysing van risikoareas met betrekking tot degradasie van omgewingskwaliteit as gevolg van landbouaktiwiteite. Alles inaggenome, was die belangrikste doel van die studie om 'n metodiek te ontwikkel vir die evaluering en identifisering van boerderygebiede waarin die volhoubare benutting van die natuurlike hulpbronne bedreig word deur huidige produksiepraktyke. Die resultaat was 'n model wat landboupraktyke deur 'n holistiese benadering ten opsigte van die impak op die omgewing evalueer. Vir toepassing van die metodologie is die Piketbergse landdrosdistrik as studiearea geïdentifiseer. Verskeie datastelle, onder andere klimaat, grondtipes, waterkwaliteit, plantegroei en landboupraktyke, spesifiek aan hierdie area is verkry. Deur Geografiese Inligtingstelsels is die datastelle gemanipuleer en die toepaslike inligting afgelei vir gebruik in die model. Die eindresultaat was verskeie kaarte waarop die potensiële impak van landbou op die omgewing van hoog na laag geklassifiseer is. Spesifieke landboupraktyke verantwoordelik vir die impak, hetsy hoog of laag word ook aangedui.
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Tecnologia para o controle químico de plantas invasoras / Technology for the chemical control of invasive plants

Coltro, Ivan 25 April 2017 (has links)
A agricultura brasileira desenvolve um papel muito importante na economia nacional e melhorar os processos de produção é algo que se busca continuamente. Métodos que auxiliem o manejo adequado das culturas visando uma maior produtividade e redução de custos é algo imprescindível para uma agricultura mais competitiva. O controle de plantas invasoras está entre os fatores que mais influenciam na lucratividade de uma cultura, pois se realizada de modo ineficiente, pode inviabilizar a atividade. O uso de sensores que automatizam alguns dos diversos processos realizados no campo vem tomando força na agricultura moderna e contribuindo para as produções recordes registradas atualmente, mas que na maioria dos casos são inacessíveis a grande maioria dos produtores. Neste trabalho foi desenvolvido um protótipo que automatiza o processo de aplicação controlada de herbicida, com um custo 13,53% em relação aos principais equipamentos comerciais que realizam tal função. Trata-se de um equipamento desenvolvido com hardware e software livre, que realiza a captura e processamento digital de imagens, promovendo a identificação de plantas invasoras e aplicação localizada de herbicidas não seletivos. A coleta das imagens é realizada por uma webcam controlada pela placa Raspberry, que também realiza o processamento digital destas imagens com o auxílio do software Opencv. O equipamento possui também uma válvula solenoide que controla o fluxo de herbicida. Toda a construção e testes foram realizados no município de Vera Cruz do Oeste, no Paraná. A velocidade máxima obtida nos testes foi de 4 km/h, pouco se comparado aos 25 km/h dos equipamentos comerciais, detectando plantas com área folhar com no mínimo 3 cm², um resultado muito semelhante aos principais equipamentos comerciais presentes no mercado. Apresar da baixa velocidade de operação, o equipamento se mostrou viável em sua utilização, pois pode gerar lucro com a economia de herbicida em aproximadamente dois anos, dependendo da área e grau em que se dá a utilização do equipamento. / Brazilian agriculture plays a very important role in the national economy and improving the production processes is something that is continuously sought. Methods that help the proper management of crops for greater productivity and cost reduction are essential for a more competitive agriculture. The control of invasive plants is among the factors that most influence the profitability of a crop, because if it is carried out in an inefficient way, it can make the activity unfeasible. The use of sensors that automate some of the various processes carried out in the field has been taking hold in modern agriculture and contributing to the record productions currently recorded, but in most cases are inaccessible to the great majority of producers. In this work a prototype was developed that automates the process of controlled application of herbicide, with a cost of 13.53% in relation to the main commercial equipment that perform such function. It is an equipment developed with hardware and free software, which performs the digital capture and processing of images, promoting the identification of invasive plants and localized application of non-selective herbicides. The images are collected by a webcam controlled by the Raspberry card, which also performs the digital processing of these images with the help of Opencv software. The equipment also has a solenoid valve that controls the flow of herbicide. All the construction and tests were carried out in the municipality of Vera Cruz do Oeste, Paraná. The maximum speed obtained in the tests was of 4 km / h, little compared to the 25 km / h of commercial equipment, detecting plants with leaf area with at least 3 cm², a result very similar to the main commercial equipment present in the market. In order to achieve a low operating speed, the equipment proved to be viable in its use, since it can generate profit from the herbicide economy in approximately two years, depending on the area and degree of use of the equipment.
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A construção de um Indice de Sustentabilidade Ambiental Agricola (ISA) : uma proposta metodologica / The construction of the agricultural environmental sustainability index (ISAGRI) : a methodological proposal

Silva, Luciana Ferreira da 03 February 2007 (has links)
Orientador: Ademar Ribeiro Romeiro / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Economia / Made available in DSpace on 2018-08-08T08:32:24Z (GMT). No. of bitstreams: 1 Silva_LucianaFerreirada_D.pdf: 1821160 bytes, checksum: 7f30e728bf1f4ce65d49b21421459662 (MD5) Previous issue date: 2007 / Resumo: Esse trabalho apresenta a metodologia de construção do Índice de Sustentabilidade Ambiental Agrícola ISAGRI e realiza aplicação teste do mesmo para as microbacias dos rios Oriçanga e Araras, ambas pertencentes à Bacia dos rios Mogi Guaçu-Pardo ¿ SP. Esta é uma área representativa de diferentes situações encontradas no Estado de São Paulo. A região apresenta praticamente todas as grandes províncias geomorfológicas do Estado, com grande variação de solos, topografia e vegetação. Apresenta também uma diversidade de sistemas agrícolas, com os mais variados usos de solo e diferentes tipos de agricultores. Metodologicamente o ISAGRI foi construído utilizando-se do escopo teórico de indicadores de estado, pressão e resposta (PER) proposto pela OCDE. Trata-se de um índice sintético composto por 8 indicadores divididos em 3 dimensões: estado, pressão e resposta. Esses indicadores foram transformados em índices, e então, agregados as dimensões a que pertencem, gerando assim três novos índices ¿ IEA (Índice de estado do ecossistema agrícola; IDEG (Índice de vetores de degradação) e ICOR (Índice de medidas de prevenção e correção). O ISAGRI é, assim, o resultado da média simples dos índices dessas dimensões. O teste permitiu a comparação dos níveis de sustentabilidade ambiental agrícola entre as duas microbacias, sendo que a microbacia do rio de Araras apresentou os melhores resultados e, portanto, melhor sustentabilidade ambiental. Ao final, propõem-se critérios de categorização de níveis de sustentabilidade / Abstract: This study presents the methodology of construction of the Agricultural Environmental Sustainability Index (ISAGRI). This Index was evaluated in the watersheds of the rivers Oriçanga and Araras, both belonging to the Mogi Guaçu river basin. This is a representative area of different situations found in the State of São Paulo. The region presents practically all the great geomorphic provinces of the State, with great variation of ground, topography and vegetation. It also presents a diversity of agricultural systems, with the most varied uses of the ground and different types of agriculturists. The methodology of the ISAGRI was constructed using the theoretical target of indicators of state, pressure and response (PER) considered by the OCDE. The ISAGRI is synthetic index composed of 8 indicators divided in 3 dimensions: state, pressure and response. These indicators have been transformed into indices, and then, added to the dimensions to which they belong, thus generating three new indices - IEA (Index of state of the agricultural ecosystem; IDEG (Index of degradation vectors) and ICOR (Index of measures of prevention and correction). The ISAGRI is thus, the result of the simple average of the indices of these dimensions. The test allowed the comparison of the levels of agricultural environmental sustainability between the two watersheds, being that the Araras¿s watershed presented the best results and, therefore, better environmental sustainability. At the end, the different levels of sustainability were categorized in criteria of sustainability / Doutorado / Desenvolvimento Economico, Espaço e Meio Ambiente / Doutor em Economia Aplicada

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