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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.
71

A agricultura familiar do Serid? potiguar: vulnerabilidade, percep??o e adapta??o ?s mudan?as clim?ticas / Family farming at the Serido s region of Rio Grande do Norte: vulnerability, perception and adaptation to climate change

Andrade, Anna J?ssica Pinto de 05 March 2013 (has links)
Made available in DSpace on 2014-12-17T15:55:03Z (GMT). No. of bitstreams: 1 AnnaJPA_DISSERT.pdf: 4374448 bytes, checksum: 0394dbcd3eebb9c5bf4ba04fccb3a5c2 (MD5) Previous issue date: 2013-03-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / At the semiarid regions of developing countries the rural population has always been vulnerable to the climatic variations e its consequences. The effects of the semiarid climate, together with other biophysics, social and political-economic factors, impair the agricultural production, generating a situation of food insecurity and poverty in the rural areas. With the occurrence of climate change, natural resources of the semiarid regions can became scarcer, what would directly affect the agricultural production and those who depend on it. Therefore, the present study sought to study one of the most susceptible areas to the effects of the semiarid climate and desertification of Rio Grande do Norte, the potiguar s Serido. The study aimed to analyze the socioeconomic and environmental factors that put farmers in a position of vulnerability to the effects of climate; assess their perceptions about climate variations that have already occurred and their knowledge about climate change and global warming, also to identify which adaptation strategies to climate they have adopted at the rural establishment. The survey was conducted in 29 communities of four counties of the potiguar s Serido Caico, Parelhas, Lagoa Nova and Acari. Semi-structured interviews were conducted with local leaders and 241 questionnaires were applied with the family farmers. It was found that in addition to environmental factors such as the scarcity of water resources and climatic conditions, other factors such as the environmental degradation, the small size of the properties, the lack of technical assistance and financial resources and also the low education levels reduce the resilience capacity of family farming to the effects of the Semiarid climate. With the occurrence of climate change, the challenges for family farming at Serido will intensify. If farmers cannot adapt, the impacts may preclude this category of agricultural production causing serious harm to food security and further increasing the vulnerability situation of these populations. Although the farmers perceived changes in climate, the lack resources and information appears as the main reasons preventing the adoption of adaptation strategies. The lack of knowledge about climate change and global warming and the impacts that these phenomena may cause are also limiting factors for adaptation. It is therefore essential to identify the factors that influence the adoption of adaptation strategies, and seek alternatives to living with the semiarid that can strengthen the resilience of family farming and social reproduction that allow agricultural segment, even in a climate change scenario / Nas regi?es semi?ridas dos pa?ses em desenvolvimento as popula??es rurais sempre estiveram vulner?veis ?s varia??es clim?ticas e suas consequ?ncias. Os efeitos do clima Semi?rido, aliados ? outros fatores biof?sicos, sociais, pol?ticos e econ?micos, prejudicam a produ??o agr?cola, gerando uma situa??o de inseguran?a alimentar e pobreza no meio rural. Com o advento das mudan?as clim?ticas, os recursos naturais das regi?es semi?ridas poder?o se tornar ainda mais escassos, o que afetaria diretamente a produ??o agr?cola e os que dela dependem. Nesse contexto, a presente pesquisa buscou estudar uma das ?reas mais suscept?veis aos efeitos do clima semi?rido e da desertifica??o do Rio Grande do Norte, o Serid? potiguar. O estudo teve como objetivo analisar os fatores socioecon?micos e ambientais que colocam os agricultores familiares numa situa??o de vulnerabilidade aos efeitos do clima; avaliar suas percep??es sobre as varia??es clim?ticas j? ocorridas e seus conhecimentos sobre mudan?as clim?ticas e aquecimento global, al?m de verificar quais as estrat?gias de adapta??o ao clima foram realizadas no ?mbito do estabelecimento rural. A pesquisa foi realizada em 29 comunidades de quatro munic?pios do Serid? potiguar Caic?, Parelhas, Lagoa Nova e Acari. Foram realizadas entrevistas semiestruturadas com lideran?as locais e aplicados 241 question?rios com os agricultores familiares. Verificou-se que al?m dos fatores ambientais como a escassez dos recursos h?dricos e as condi??es clim?ticas outros fatores como degrada??o ambiental o tamanho reduzido das propriedades, a falta de assist?ncia t?cnica e de recursos financeiros, al?m do baixo n?vel de escolaridade dos agricultores reduzem a capacidade de resili?ncia da agricultura familiar aos efeitos do clima Semi?rido. Com a ocorr?ncia das mudan?as clim?ticas, os desafios para a agricultura familiar do Serid? potiguar ir?o se intensificar e, caso os agricultores n?o consigam se adaptar, os impactos poder?o impossibilitar a produ??o agr?cola dessa categoria, causando graves preju?zos para a seguran?a alimentar e aumentando ainda mais a situa??o de vulnerabilidade dessas popula??es. Apesar de perceberem as altera??es no clima, a limita??o de recursos financeiros e a falta de informa??es aparecem como principais impedimentos ? ado??o de estrat?gias de adapta??o. A falta de conhecimento sobre as mudan?as clim?ticas, aquecimento global e sobre os impactos que esses fen?menos podem causar tamb?m s?o fatores limitantes ? adapta??o. Torna-se assim, essencial identificar os fatores que influenciam a ado??o de estrat?gias de adapta??o, al?m de buscar alternativas para a conviv?ncia com o semi?rido que possam fortalecer a resili?ncia da agricultura familiar e permitir reprodu??o social desse segmento agr?cola, mesmo num cen?rio de mudan?as clim?ticas
72

Avalia??o do desenvolvimento da regi?o de Cruzeta (RN), atrav?s do uso intensivo de ?gua para irriga??o / Evaluation of Cruzeta Region (RN) development through intensive use of water for irrigation

Ara?jo, Carlos Alberto Batista de 04 April 2007 (has links)
Made available in DSpace on 2014-12-17T15:03:18Z (GMT). No. of bitstreams: 1 CarlosAlbertoBA.pdf: 931437 bytes, checksum: 7ce2bcd537fa9aeb002e3cff8e09ad45 (MD5) Previous issue date: 2007-04-04 / This work aims for the evaluation of Cruzeta Irrigated Perimeter, RN, which consists in the efficient use of water for agricultural production. The goal is looking for the available quantity of water for supplying required demands for adequate and economically viable cultures for the region. It is supposed that regional community water is supplied by pipelines from sources located outside of the region. From this study it is recommended the implantation of adequate installments for culture management in accordance with the availability of water resources and others conditionings. It must be considered the intensity of rainy and drought seasons in order to adjust the cultivated area and equipments to be operated, and also, the use of operating models and simulations in order to establish alert levels and eventually, reduction of irrigated area. Based on obtained data it is proposed the cultivation of different types of non-permanent cultures so that temporary cultures would be extensively produced in periods of abundant reservoir storage water permitting the transformation of storage water in storage culture products and few or no production in severe drought periods. This is the basic premise for sustainable agricultural development for Brazilian semiarid region / Este trabalho visa ? avalia??o do Per?metro Irrigado Cruzeta, RN, que consiste na utiliza??o eficiente da ?gua para a produ??o agr?cola, equacionando a quantidade dispon?vel de ?gua para atender a demanda requerida de um plantio adequado e economicamente vi?vel ? regi?o. Admite-se que a ?gua para abastecimento da popula??o seja provida por fonte ex?gena atrav?s de adutoras. Com base nesse estudo ser? recomendada a implanta??o de instala??es adequadas ao manejo de culturas a serem exploradas de acordo com a disponibilidade h?dricas e demais condicionantes, devendo-se levar em considera??o as esta??es secas e os anos de seca, onde as instala??es ficar?o parcialmente ou totalmente inativas; a constru??o de modelos de opera??o que se ajustem ?s esta??es chuvosas e secas e o estabelecimento de n?veis de alerta para a redu??o gradual da ?rea irrigada. Com base nos dados do estudo prop?e-se a produ??o de tipos de agricultura irrigada n?o permanentes, ou seja, culturas tempor?rias seriam extensivamente produzidas durante per?odos com grande armazenamento de ?gua, transformando ?gua represada em produtos estocados e pouca ou nenhuma produ??o durante os per?odos prolongados de seca. Essa ? a premissa b?sica de desenvolvimento agr?cola sustentado para o semi-?rido
73

An?lise da precipita??o no semi-?rido potiguar

Garcia, Joema Ferreira da Costa 30 June 2011 (has links)
Made available in DSpace on 2014-12-17T15:03:27Z (GMT). No. of bitstreams: 1 JoemaFCG_DISSERT.pdf: 801033 bytes, checksum: d6b34753910a92ddda7617d160f165bb (MD5) Previous issue date: 2011-06-30 / The semiarid rainfall regime is northeastern Brazil is highly variable. Climate processes associated with rainfall are complex and their effects may represent extreme situations of drought or floods, which can have adverse effects on society and the environment. The regional economy has a significant agricultural component, which is strongly influenced by weather conditions. Maximum precipitation analysis is traditionally performed using the intensity-duration-frequency (IDF) probabilistic approach. Results from such analysis are typically used in engineering projects involving hydraulic structures such as drainage network systems and road structures. On the other hand, precipitation data analysis may require the adoption of some kind of event identification criteria. The minimum inter-event duration (IMEE) is one of the most used criteria. This study aims to analyze the effect of the IMEE on the obtained rain event properties. For this purpose, a nine-year precipitation time series (2002- 2011) was used. This data was obtained from an automatic raingauge station, installed in an environmentally protected area, Ecological Serid? Station. The results showed that adopted IMEE values has an important effect on the number of events, duration, event height, mean rainfall rate and mean inter-event duration. Furthermore, a higher occurrence of extreme events was observed for small IMEE values. Most events showed average rainfall intensity higher than 2 mm.h-1 regardless of IMEE. The storm coefficient of advance was, in most cases, within the first quartile of the event, regardless of the IMEE value. Time series analysis using partial time series made it possible to adjust the IDF equations to local characteristics / O regime pluviom?trico no semi-?rido Nordestino ? altamente vari?vel. Os processos clim?ticos associados ?s precipita??es s?o complexos e seus efeitos podem representar situa??es limites de seca ou enchentes, os quais podem ter efeitos negativos para a sociedade e meio ambiente. A economia da regi?o, com forte componente agr?rio, ? fortemente impactada pelas condi??es clim?ticas. A an?lise de chuvas intensas ? feita tradicionalmente utilizando as equa??es tipo intensidadedura??o- freq??ncia (IDF). Os resultados obtidos nesses estudos s?o usados em projetos de engenharia envolvendo obras hidr?ulicas, tais como rede de drenagem e obras vi?rias. Por outro lado, a an?lise dos dados de precipita??o pode exigir a ado??o de algum tipo de crit?rio de identifica??o de eventos. Um dos crit?rios mais usados ? o intervalo m?nimo entre eventos (IMEE). Este estudo tem o objetivo de analisar o efeito do IMEE nas caracter?sticas dos eventos de precipita??o. Para isso, foi usada uma serie hist?rica de precipita??o com 9 anos de registros (2002-2011). Os dados foram registrados numa esta??o pluviogr?fica autom?tica instalada na Esta??o Ecol?gica do Serid?. Os resultados demonstraram que o valor do IMEE adotado tem um efeito importante no numero de eventos, dura??o, altura precipitada, intensidade m?dia e no intervalo m?dio entre eventos. Al?m disso, verificou-se uma maior ocorr?ncia de eventos extremos para pequenos valores de IMEE. A maioria dos eventos apresentou intensidade m?dia acima de 2 mm/h, independente do IMEE adotado. O coeficiente de avan?o da tormenta situou-se, na maioria dos casos, no primeiro quartil do evento, independente do valor do IMEE. A an?lise probabil?stica dos dados observados utilizando s?ries parciais possibilitou o ajuste de equa??es IDF caracter?sticas do local
74

Estimativa da evapotranspira??o espacial em uma regi?o semi?rida utilizando sensoriamento remoto

Bezerra, H?lio Nogueira 26 April 2013 (has links)
Made available in DSpace on 2014-12-17T15:03:31Z (GMT). No. of bitstreams: 1 HelioNB_DISSERT.pdf: 3257032 bytes, checksum: c4c8b0f640d55be078cd61d2e68686c0 (MD5) Previous issue date: 2013-04-26 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / With the need to deploy management and monitoring systems of natural resources in areas susceptible to environmental degradation, as is the case of semiarid regions, several works have been developed in order to find effective models and technically and economically viable. Therefore, this study aimed to estimate the daily actual evapotranspiration (ETr) through the application of the Surface Energy Balance Algorithm for Land (SEBAL), from remote sensing products, in a semiarid region, Serid? of the Rio Grande do Norte, and do the validation of these estimates using ETr values obtained by the Penman-Monteith (standard method of the Food and Agriculture Organization-FAO). The SEBAL is based on energy balance method, which allows obtaining the vertical latent heat flux (LE) with orbital images and, consequently, of the evapotranspiration through the difference of flows, also vertical, of heat in the soil (G), sensitive heat (H) and radiation balance (Rn). The study area includes the surrounding areas of the Dourado reservoir, located in the Currais Novos/RN city. For the implementation of the algorithm were used five images TM/Landsat-5. The work was divided in three chapters in order to facilitate a better discussion of each part of the SEBAL processing, distributed as follows: first chapter addressing the spatio-temporal variability of the biophysical variables; second chapter dealing with spatio-temporal distribution of instant and daily radiation balance; and the third chapter discussing the heart of the work, the daily actual evapotranspiration estimation and the validation than to the study area / Com a necessidade de se implantar sistemas de monitoramento e gest?o dos recursos naturais em ?reas suscept?veis ? degrada??o ambiental, como ? o caso das regi?es semi?ridas, diversos trabalhos t?m sido desenvolvidos a fim de encontrar modelos eficazes e vi?veis t?cnica e economicamente. Diante disso, este trabalho teve como objetivo estimar a evapotranspira??o real (ETr) di?ria atrav?s da aplica??o do Surface Energy Balance Algorithm for Land (SEBAL), a partir de produtos de sensoriamento remoto, em uma regi?o semi?rida, Serid? norte rio-grandense, e fazer a valida??o dessas estimativas utilizando valores de ETr obtidos pelo m?todo de Penman-Monteith (m?todo padr?o da Food and Agriculture Organization - FAO). O SEBAL baseia-se no m?todo do balan?o de energia, que possibilita a obten??o do fluxo vertical de calor latente (LE) com imagens orbitais e, consequentemente, da evapotranspira??o, atrav?s da diferen?a dos fluxos, tamb?m verticais, de calor no solo (G), calor sens?vel (H) e o saldo de radia??o (Rn). A ?rea de estudo compreende o entorno do reservat?rio Dourado, situado no munic?pio de Currais Novos/RN. Para a implementa??o do algoritmo foram utilizados cinco imagens TM/Landsat-5. O trabalho foi divido em tr?s cap?tulos a fim de possibilitar uma melhor discuss?o de cada parte do processamento do SEBAL, ficando assim distribu?dos: primeiro cap?tulo abordando a variabilidade espa?o-temporal das vari?veis biof?sicas; segundo cap?tulo tratando da distribui??o espa?o-temporal do saldo de radia??o instant?neo e di?rio; e o terceiro cap?tulo discutindo o cerne do trabalho, a estimativa da evapotranspira??o real di?ria e a valida??o da mesma para a ?rea estudada
75

Assessing Land-Atmosphere Interactions through Distributed Footprint Sampling at Two Eddy Covariance Towers in Semiarid Ecosystems of the Southwestern U.S.

January 2013 (has links)
abstract: Land-atmosphere interactions of semiarid shrublands have garnered significant scientific interest. One of the main tools used for this research is the eddy covariance (EC) method, which measures fluxes of energy, water vapor, and carbon dioxide. EC fluxes can be difficult to interpret due to complexities within the EC footprint (i.e. the surface conditions that contribute to the flux measurements). Most EC studies use a small number of soil probes to estimate the land surface states underlying the measured fluxes, which likely undersamples the footprint-scale conditions, especially in semiarid shrublands which are characterized by high spatial and temporal variability. In this study, I installed a dense network of soil moisture and temperature probe profiles in the footprint region of an EC tower at two semiarid sites: a woody savanna in southern Arizona and a mixed shrubland in southern New Mexico. For data from May to September 2013, I link land surface states to EC fluxes through daily footprints estimated using an analytical model. Novel approaches are utilized to partition evapotranspiration, estimate EC footprint soil states, connect differences in fluxes to footprint composition, and assess key drivers behind soil state variability. I verify the hypothesis that a small number of soil probes poorly estimates the footprint conditions for soil moisture, due to its high spatial variability. Soil temperature, however, behaves more consistently in time and space. As such, distributed surface measurements within the EC footprint allow for stronger ties between evapotranspiration and moisture, but demonstrate no significant improvement in connecting sensible heat flux and temperature. I also find that in these systems vegetation cover appears to have stronger controls on soil moisture and temperature than does soil texture. Further, I explore the influence of footprint vegetation composition on the measured fluxes, which reveals that during the monsoon season evaporative fraction tends to increase with footprint bare soil coverage for the New Mexico site and that the ratio of daily transpiration to evapotranspiration increases with grass coverage at the Arizona site. The thesis results are useful for understanding the land-atmosphere interactions of these ecosystems and for guiding future EC studies in heterogeneous landscapes. / Dissertation/Thesis / M.S. Civil and Environmental Engineering 2013
76

Zoning geoecolÃgico as subsidy to the environmental planning on scope municipal / Zoneamento GeoecolÃgico com o subsÃdio para o planejamento Ambiental no Ãmbito Municipal.

Juliana Felipe Farias 18 June 2012 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / O atual quadro de exploraÃÃes desordenadas e esgotamento dos recursos naturais comprometem diretamente a dinÃmica dos sistemas ambientais, refletindo-se de maneira diversificada em todo territÃrio nacional. Em regiÃes com caracterÃsticas climÃticas mais rigorosas, como no caso do semiÃrido cearense, o uso e ocupaÃÃo desordenados vÃm ocasionando problemas diversos que comprometem a dinÃmica dos sistemas ambientais e a qualidade de vida da populaÃÃo. Partindo da necessidade de elaborar propostas de planejamento e gestÃo ambiental de municÃpios inseridos no semiÃrido, o presente trabalho foi realizado no municÃpio de Nova Russas, situado na porÃÃo centro-oeste do estado do CearÃ, na latitude 4Â42â24â S e longitude 40Â33â47â W, com Ãrea de 742,69 kmÂ, distante da cidade de Fortaleza cerca de 300 km. O municÃpio possui uma sÃrie de problemas como: poluiÃÃo, contaminaÃÃo e ocupaÃÃo desordenada das planÃcies fluviais, utilizaÃÃo de tÃcnicas de manejo do solo inadequadas, dentre outros. A pesquisa foi efetivada no municÃpio a partir do levantamento detalhado das caracterÃsticas naturais, socioeconÃmicas e culturais, embasada nos procedimentos teÃricos e metodolÃgicos da Geoecologia das Paisagens. A visÃo sistÃmica e integrada viabilizou a elaboraÃÃo de mapas temÃticos na escala de 1:170.000 e de uma proposta de zoneamento geoecolÃgico e funcional. Para o municÃpio de Nova Russas, a pesquisa surge como um importante documento contÃm um levantamento histÃrico, socioeconÃmico e ambiental, e apresenta os principais problemas ambientais que comprometem a disponibilidade dos recursos naturais e se refletem na economia local. Sendo assim, a efetivaÃÃo da pesquisa buscou estabelecer diretrizes que conduzam o municÃpio a uma sustentabilidade geoecolÃgica a partir de um processo de ocupaÃÃo do espaÃo ambientalmente equilibrado. / The current picture of disordered holdings and depletion of natural resources directly compromising the dynamics of environmental systems, reflecting themselves on a diverse nationwide. In regions with more stringent climate haracteristics, such as the semi-arid region of CearÃ, with a prolonged dry season and a rainy concentrated in a short period of the year, coupled with geological and geomorphological factors that influence the availability of the region's natural resources, exploitation, the use and occupation are disordered causing various problems that compromise the dynamics of environmental systems and quality of life. These factors together with local economic development policies that, in most cases, are not compatible with the social and environmental reality of the area, continue to delay the development of certain areas because it does not consider the potential economic and environmental available in your territory. Starting from the need to prepare proposals for environmental planning and management of municipalities in semi-arid, the present study was designed to provide subsidies related to the actual economic and environmental study area chosen, the city of Nova Russa s, located in the portion midwestern state of CearÃ, in latitude 4 Â 42'24 "S and longitude 40 Â 33'47" W, with an area of 742.69 km Â, with average heights of 240 m, and from the city of Fortaleza about 300 km. Nova Russas presents a picture of evolution in terms of population, advancing one that comes with public policies for socio-economic sectors, cultural and environmental factors, the latter being the most affected in the process of urban expansion. The city has a number of environmental problems such: pollution, sprawl and pollution of the river plains, using techniques inadequate soil management, which accelerate erosion and cause loss of soil fertility, among others. With this framework, the research was accomplished in the city from the detailed survey of the natural characteristics, socioeconomic and cultural, based on theoretical and methodological procedures of Geoecology of Landscapes. A systemic and integrated vision of Geoecology allowed the elaboration of thematic maps in scale 1:170.000 and a zoning proposal geoecolÃgico functional and appropriate to the potential and limitations of the area, and you can also prepare an action plan and measures for integrated. In general, it is believed that the work presents itself as an important contribution to the municipal level, which can be used as a model to support the elaboration of proposals for environmental planning from the realization of zoning. For the city of Nova Russas, research emerges as an important document and contains a historical survey, socioeconomic and environmental issues, presents the main environmental problems that compromise the availability of natural resources and are reflected in the local economy. Thus, the effectiveness of the research sought to establish guidelines that will lead the council sustainability geoecolÃgica from a process of occupation of space environmentally balanced.
77

ProduÃÃo de prÃpolis por abelha melÃfera africanizada (Apis Mellifera Lineu.) na caatinga do Baixo Jaguaribe cearense / Production of propolis by the Africanized honey bee (_Apis mellifera _L.) in the caatinga vegetation of Baixo Jaguaribe region in the state of CearÃ, Brazil

Afonso OdÃrio Nogueira Lima 29 February 2012 (has links)
nÃo hà / O presente trabalho teve por objetivo estudar a produÃÃo e a qualidade da prÃpolis coletada por abelha melÃfera africanizada (Apis mellifera L.), bem como a influÃncia da coleta de prÃpolis na produÃÃo de mel, na caatinga do Baixo Jaguaribe cearense. Foram escolhidos aleatoriamente cinco nÃcleos apÃcolas com 25 colmÃias cada, padrÃo Langstroth, habitadas com abelhas melÃferas africanizadas, no municÃpio de Limoeiro do Norte - CearÃ. De cada nÃcleo, foram sorteadas vinte colÃnias, dez para a coleta de prÃpolis e mel, onde foram instalados coletores de prÃpolis, e dez para a coleta de mel. O experimento teve inÃcio em janeiro e fim em dezembro de 2010. As coletas de prÃpolis foram realizadas a cada trinta dias, determinando-se a produÃÃo e os teores de umidade, cera, massa mecÃnica, Ãndice de oxidaÃÃo, substÃncias fenÃlicas e flavonÃides, Utilizou-se as dez colmÃias de cada nÃcleo para os dados de produÃÃo e as duas colmÃias mais produtivas de cada um dos cinco nÃcleos experimentais para as anÃlises de qualidade. As colheitas de mel foram procedidas sempre que os favos das melgueiras estivessem com operculaÃÃo superior a 90%. Os resultados mostram que nÃo houve efeito significativo da interaÃÃo entre os fatores Ãpoca do ano e local, nem da Ãpoca do ano sobre a produÃÃo de prÃpolis. NÃo foram observadas diferenÃas significativas quando comparadas as produÃÃes de mel com e sem retirada de prÃpolis. Conforme a anÃlise dos dados obtidos para o teor de flavonÃides e compostos fenÃlicos, nÃo houve interaÃÃo significativa entre os fatores perÃodo e local de coleta da prÃpolis. NÃo foram observadas diferenÃas significativas entre os locais. Entretanto, observou-se diferenÃa significativa (P<0,01) entre os perÃodos do ano, sendo que na prÃpolis coletada no perÃodo chuvoso houve uma maior proporÃÃo de flavonÃides e compostos fenÃlicos. Conforme a anÃlise dos dados obtidos para o teor de umidade, cera, massa mecÃnica e tempo de oxidaÃÃo, nÃo houve interaÃÃo significativa entre os fatores perÃodo e local de coleta da prÃpolis. Entre os perÃodos tambÃm nÃo foi observado diferenÃa significativa quanto a anÃlise dos dados de umidade, massa mecÃnica e tempo de oxidaÃÃo. DiferenÃas significativas entre perÃodos e locais (P<0,05) foram observadas quanto ao teor de cera: a prÃpolis coletada no perÃodo seco mostrou um teor maior em relaÃÃo ao apresentado no perÃodo chuvoso; e, entre a quantidade de cera obtida no local MoisÃs 1, que foi o mais baixo valor, em relaÃÃo aos resultados obtidos nos locais MoisÃs 3 e Manilha 2. Quando se comparou o teor de massa mecÃnica nos locais, houve diferenÃa significativa (P<0,05), sendo que a prÃpolis coletada no nÃcleo MoisÃs 1 apresentou uma maior proporÃÃo de massa mecÃnica em relaÃÃo aos demais locais que nÃo diferiram entre si. TambÃm na comparaÃÃo entre locais, o tempo de oxidaÃÃo apresentou diferenÃa significativa (P<0,05), sendo que a prÃpolis coletada no nÃcleo Altamira 2 mostrou menor tempo de oxidaÃÃo em relaÃÃo aos demais locais. Concluiu-se que: quantitativamente, a produÃÃo de prÃpolis na caatinga do Baixo Jaguaribe cearense nÃo sofre influÃncia das estaÃÃes seca e chuvosa, mas pode ser influenciada pelo local de instalaÃÃo do apiÃrio; qualitativamente, a qualidade da prÃpolis coletada na caatinga do Baixo Jaguaribe cearense sofre influÃncia da sazonalidade e do local de instalaÃÃo dos apiÃrios, sendo a estaÃÃo chuvosa a que apresenta melhores resultados qualitativos; e, a coleta de prÃpolis nÃo interfere na produÃÃo de mel. / The present work aimed to study the production and quality of propolis collected by the Africanized honey bee (Apis mellifera L.) in the caatinga vegetation of Baixo Jaguaribe region in the state of CearÃ, Brazil, as well as any influence of propolis collection on honey production. Five apiaries, each of them containing 25 Africanized honey bee colonies inhabiting Langstroth standard hives, were chosen in the county of Limoeiro do Norte - CearÃ. From each apiary, 20 colonies were chosen at random, 10 for propolis and honey production, which received propolis collecting devices, and tem only for honey production. The experiment initiated in January and ended in December 2010. Propolis collection was carried out at every 30 days, when it was detemined the amount produced as well as contents of humidity, wax, mechanic mass, oxidation Ãndex, phenolic substances and flavonoids. Propolis production was obtained from the 10 colonies of each apiary and propolis quality from the two most productive ones. Honey harvestings were carried out when combs in the supers were over 90% capped. Results showed no significant effect of interaction between the factors period of the year and place, nor period of the year and propolis production. No significant difference was found between honey production from colonies producing propolis to those under no propolis colection. According to the data analyses otained for flavonoid and phenolic componds contents, there was no significant interaction between the factors period and place of propolis collection. There was no significant differences between places (apiaries). However, there was a significant difference (P<0,01) between the periods of the year, in a way that the propolis collected during the rainy season showed a greater flavonoid and phenolic compounds proportion. Data analyses for humidity, wax, mechanic mass and oxidation time showed no significant interaction between the factors period and place of propolis collection. The same happened to humidity, wax, mechanic mass and oxidation time in regard to the periods of the year. Significant differences between periods and places (P<0,05) were observed to wax content: propolis collected during the dry season showed a higher wax content in relation to that propolis collected dring the rainy season.; and, between the amount of wax obtained in the apiary MoisÃs 1, the one with lower wax content, in relation to the apiaries MoisÃs 3 and Manilha 2. When the content of mechanic mass was compared in the apiaries, there was significant difference (P<0,05), and the propolis collected in the apiary MoisÃs 1 showed a higher proportion of mechanic mass in relation to the other four apiaries, which did not differ among them. Also, in the comparison among places, time of oxidation varied significantly (P<0,05), and the propolis collected in Altamira 2 presented lower oxidatioin time in relation to the other places. It is concluded that: quantitative propolis production in the caatinga vegetation of the Baixo Jaguaribe region is not influenced by the dry and rainy seasons, but can be affected by the place where apiaries are installed; qualitatively, the propolis produced in the caatinga vegetation of Baixo Jaguaribe region is influenced by the sazonality and place where the apiaries are installed, and the rainy season produced the best quality propolis; and, propolis collection does not interfere with honey production
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Productivity, nutrient cycling and emergy efficiency as functions of plant diversity in agricultural systems and preserved caatinga vegetation / Produtividade, ciclagem de nutrientes e eficiÃncia emergÃtica em funÃÃo da diversidade vegetal em sistemas agrÃcolas e caatinga conservada.

Maria Ivanilda de Aguiar 19 December 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Nutrient cycling and energy transformation processes fuel plant productivity and are directly related to ecosystem diversity. The preservation of diversity has thus been identified as a way to improve the sustainability of agroecosystems. It also follows that agroforestry systems (AFS) are recommended since they maintain high plant diversity, increase carbon and nutrient stocks and promote emergy efficiency. Agroforestry systems represent an alternative to traditional agricultural systems, which are responsible for large losses of diversity and environmental degradation in Brazilâs semiarid northeast. It is assumed that the greater plant diversity in AFS yields greater productivity, improves soil nutrient inputs, and increases carbon and nutrient stocks as well as energy efficiency. We evaluated a model agroforestry production system consisting of three areas: agrosilvopastoral, silvopastoral and preserved caatinga vegetation (CAT). Also, data was taken from a traditional management system including an area under cropping and two areas under fallow for six and nine years. The objectives of this work were to assess whether AFS remain similar to preserved vegetation and whether fallow periods restore land to its initial condition, in terms of: (i) the species composition and community structure of herbaceous and tree/shrub strata; (ii) plant diversity and biomass production; (iii) carbon and nutrient stocks in standing vegetation, litter and the soil and (iv) emergy flux transformations. We found that species composition and plant productivity were similar in the AFS and preserved caatinga, however in AFS the structure of the plant community was modified and diversity indices were reduced. Soil carbon and nutrient stocks in AFS were similar to those in CAT, but stocks in standing biomass and litter were lower. Overall, the AFS performed better in terms of emergy, due to more efficient energy use, a lesser environmental impact and greater renewability. The fallow periods following traditional cropping allowed the species composition, productivity and carbon and nutrient stocks in soil and litter to recover. However, areas under fallow differed from CAT in terms of tree community structure, with a greater number of individuals and species. Tree species found in fallow areas reach smaller sizes than under CAT. Therefore total biomass and carbon and nutrient stocks were lesser under fallow than CAT. Agroforestry systems managed in an integrated fashion represent great potential for sustainability, since they provide agricultural, pastoral and wood products while maintaining vegetation structure characteristics which allow constant fluxes of energy and nutrient cycling, as occurs under preserved vegetation. / Os processos de ciclagem de nutrientes e transformaÃÃes energÃticas impulsionam a produtividade e estÃo diretamente relacionados com a diversidade dos ecossistemas. Assim, tem-se priorizado a manutenÃÃo da diversidade em Ãreas agrÃcolas para a conduÃÃo de agroecossistemas mais sustentÃveis. Neste sentido, os sistemas agroflorestais (SAFs) sÃo recomendados por manter elevados nÃveis de diversidade vegetal, aumentar os estoques de carbono e nutrientes e promover eficiÃncia nas transformaÃÃes energÃticas. Os SAFs sÃo indicados para substituÃr os sistemas agrÃcolas tradicionais responsÃveis por grande perda de diversidade e degradaÃÃo ambiental na regiÃo semiÃrida nordestina. Espera-se que nos SAFs, a maior diversidade vegetal proporcione maior produtividade, maior retorno de nutrientes ao solo, maiores estoques de carbono e nutrientes e melhor eficiÃncia emergÃtica. Um modelo de produÃÃo agroflorestal composto de trÃs Ãreas foi avaliado: agrossilvipastoril (ASP), silvipastoril (SP) e caatinga conservada (CAT); e um sistema de manejo tradicional, composto de uma Ãrea em cultivo (AG), e duas Ãreas em pousio de seis (P6) e nove (P9) anos. Este trabalho objetivou verificar se os SAFs mantÃm-se semelhantes a vegetaÃÃo conservada e se os perÃodos de pousio retornam as Ãreas a sua condiÃÃo inicial, quanto a: (1) composiÃÃo florÃstica e estrutura da comunidade dos componentes herbÃceos e arbÃreo/arbustivo; (2) diversidade e produÃÃo de biomassa; (3) estoques de carbono e nutrientes presentes nas plantas, serrapilheira e solo e (4) transformaÃÃes dos fluxos emergÃticos. Verificou-se que as Ãreas sob SAFs apresentam composiÃÃo florÃstica e produtividade semelhante a caatinga conservada, porÃm este manejo provoca modificaÃÃes estruturais na comunidade vegetal e reduÃÃo nos Ãndices de diversidade. Os estoques de carbono e nutrientes nos SAFs sÃo semelhantes a CAT no compartimento solo, porÃm foram inferiores nas plantas e na serrapilheira. Contudo, o modelo agroflorestal apresenta melhor desempenho emergÃtico devido sua melhor eficiÃncia na utilizaÃÃo de energia, menor impacto ambiental e maior renovabilidade. Durante os perÃodos de pousio adotados apÃs o cultivo tradicional as Ãreas se recuperaram em relaÃÃo a composiÃÃo florÃstica, a produtividade e os estoques de carbono e nutrientes no solo e na serrapilheira. Entretanto, apresentaram modificaÃÃes quanto a estrutura da comunidade arbÃrea, com maior nÃmero de indivÃduos e espÃcies, sendo estes de menor porte e assim, menor biomassa total e menor estoques de carbono e nutrientes. Os sistemas de produÃÃo agroflorestal utilizados de forma integrada apresentam grande potencial de sustentabilidade, por proporcionarem a produÃÃo agrÃcola, pastoril e madeireira, mantendo diversas caracterÃsticas estruturais da vegetaÃÃo que permitem um fluxo de energia e uma ciclagem de nutrientes constante, assim como em Ãreas conservadas.
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Proposta de Ãndice de priorizaÃÃo de Ãreas para saneamento rural: estudo de caso assentamento 25 de maio, CE. / Propose of an index for prioritizing areas for rural sanitation: study case on the 25 de Maio rural settlement (Madalena, Cearà State)

Laldiane de Souza Pinheiro 25 April 2011 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A escassez hÃdrica de regiÃes semiÃridas associada a ausÃncia de saneamento tornam os reservatÃrios vulnerÃveis a contaminaÃÃo, implicando na eutrofizaÃÃo e prejuÃzos à saÃde pÃblica para as comunidades que os utilizam. Surge a necessidade de mecanismos possÃveis de identificar quais reservatÃrios encontram-se em situaÃÃo mais crÃtica para implementaÃÃo de aÃÃes de controle e reversÃo desse processo. A dificuldade de priorizar Ãreas para implantaÃÃo de saneamento rural à um fator que prejudica ou limita as intervenÃÃes governamentais, em virtude da escassez de instrumentos de gestÃo e planejamento. Desta forma, a pesquisa propÃs a construÃÃo de um Ãndice de priorizaÃÃo de Ãreas para o saneamento rural - IPAS, incorporando as dimensÃes ambientais, socioculturais e socioeconÃmicas. A Ãrea de estudo compreende o assentamento rural 25 de Maio, Madalena-Ce, que abrange uma Ãrea de 23.000 ha, onde vivem 586 famÃlias, organizadas em 13 comunidades. Para compor o Ãndice, foram realizados diagnÃsticos das condiÃÃes de saneamento, anÃlise da qualidade da Ãgua de cisternas e aÃudes, levantamento de dados hidrolÃgicos, uso e ocupaÃÃo do solo, taxa de exportaÃÃo de nutrientes e de capital social. Os resultados apontaram uma deficiÃncia dessas comunidades quanto ao abastecimento de Ãgua, destino dos resÃduos sÃlidos e esgotamento sanitÃrio. Nas cisternas, principal fonte de Ãgua para o consumo direto, os resultados indicaram a presenÃa de matÃria orgÃnica e de coliformes termotolerantes, classificando 30% das cisternas com condiÃÃes sanitÃrias insatisfatÃria, em virtude do manejo inadequado das mesmas. A oferta hÃdrica provÃm dos pequenos e micro reservatÃrios e a qualidade da Ãgua destes foi melhor no perÃodo seco do que chuvoso. As atividades desenvolvidas nas bacias dos aÃudes do assentamento estÃo contribuindo para a eutrofizaÃÃo dos mesmos, tendo a pecuÃria extensiva como a principal atividade degradadora da qualidade da Ãgua. Com o Ãndice proposto foi possÃvel identificar na ordem de hierarquia os aÃudes que merecem prioridades Ãs aÃÃes de saneamento. / Water scarcity in semiarid regions associated with lack of sanitation make reservoirs vulnerable to contamination, resulting in eutrophication and damage to communitiesâ public health that use them. Itâs necessary propose mechanisms that can help to identify which reservoirs are in the most critical situation for implementation of actions able to control and reverse this process. The difficulty of prioritizing areas for implementation of rural sanitation is a factor that affects or limits the government intervention due the lack of management tools and planning. The research propose the construction of an index for prioritizing areas for rural sanitation - IPAS, incorporating environmental, sociocultural and socioeconomic characteristics. The study area is located on the 25 de Maio rural settlement (Madalena, Cearà State) that covers an area of 23,000 ha, home to 586 families, organized in 13 communities. To compose the index, were made diagnoses of sanitation conditions, analysis of tanks and reservoirs water quality, hydrological data collection, use and occupation, rate of nutrient export and social capital. The results presented that water supply is insufficient to these communities, as disposal of waste and sewage solids are precarious too. For tanks, the main source of water, the results indicated presence of organic matter and fecal coliform, classifying 30% of the tanks with poor sanitary conditions because of inadequate management of them. The water supply comes from small and micro reservoirs and water quality of these was better in the dry than wet season. Also, activities developed in settlement ponds basins are contributing to eutrophication, with extensive livestock as the main activity of degrading water quality. In sum, the index proposed identified, by hierarchy, the reservoirs that need major priority to sanitation actions.
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Hydrological modeling of soil-water availability in the Caatinga biome / Modelagem hidrológica da disponibilidade da água do solo no bioma Caatinga

Everton Alves Rodrigues Pinheiro 27 October 2016 (has links)
Northeastern Brazil is hydrologically characterized by recurrent droughts leading to a highly vulnerable natural water resource system. The region contains the Caatinga biome, a sparsely studied ecosystem, covering an area of approximately 800,000 km2. Reduced wateravailability is projected to take place in large regions of the globe, including Northeastern Brazil. Given the strong interactions between climate and vegetation, research has addressed climate change effects on natural and agricultural ecosystems. In this context, soil hydraulic properties are essential to assess soil water flow, and thus the ability of soil to supply water to plants at potential rates under different ranges of pressure head. Based on that, the aims of this thesis are: to increase insight in water balance components for the Caatinga biome, under current and future climate scenarios; and to assess the ability of soils in supplying water to plants by the further development of an existing matric flux potential approach, followed by its application to a group of soils from two Brazilian climatic zones (semi-arid and subhumid). Both for current and future climate scenarios, hydrological simulations were performed with SWAP model parameterized for a preserved Caatinga basin of 12 km2. The validation of the simulations was performed using a dataset of daily soil-water content measurements taken at 0.2 m depth in the period from 2004 to 2012. The soil water supplying capacity was evaluated through a multilayer matric flux potential approach, coupling the soil hydraulic properties, root length density and plant transpiration. Regarding the current climate conditions, the Caatinga biome returns 75% of the annual precipitation to the atmosphere, whereas the partitioning of total evapotranspiration into its components (transpiration, evaporation and interception) on annual basis accounts for 41%, 40% and 19%, respectively. Evapotranspiration and air temperature are most sensitive to soil moisture during the periods June-September and December-January. Concerning the future climate, transpiration was enhanced by 36%, soil evaporation and interception losses reduced by 16% and 34%, respectively. The amount of precipitation returned to the atmosphere was on average 98%. For both climate scenarios, the soil-plant-atmosphere fluxes seem to be controlled by the surface soil layer (0-0.2 m) which provides, on average, 80% of the total transpiration, suggesting that the Caatinga biome may become completely soil-water pulse dominated under scenarios of reduced water availability. The matric flux potential analysis revealed that soils from the semiarid zone were able to deliver water to plants at potential rates under a wider range of bulk soil pressure head (-36 to -148 m), whereas the soils from the wetter zone showed more hydraulic restriction with limiting soil water potential above -1.5 m. For the analyzed soils, only a negligible increase in available water results from decreasing the root water potential below -150 m, therefore, in order to adapt to water-limited conditions, plant species may invest in other adaptive strategies, rather than spending energy in structures that allow a reduction of the lower suction limit in their tissues. / O Nordeste do Brasil é hidrologicamente caracterizado por secas recorrentes, tornando os recursos hídricos naturais altamente vulneráveis. Nesta região está o bioma Caatinga, ocupando uma área de aproximadamente 800.000 km2. Cenários de déficit hídrico são projetados para grandes regiões do globo, incluindo o Nordeste brasileiro. Devido às interações entre clima e vegetação, várias pesquisas têm abordado os efeitos das mudanças climáticas sobre os ecossistemas naturais e agrícolas. Neste contexto, as propriedades hidráulicas do solo são essenciais para avaliar o movimento de água, e assim a capacidade de fornecimento de água às plantas. Com base nesta contextualização, os objetivos desta tese são: simular os componentes do balanço hídrico do bioma Caatinga para cenários climáticos atuais e futuros; e avaliar a capacidade de alguns solos em fornecer água às plantas a partir de uma abordagem de potencial de fluxo matricial. Para os cenários climáticos atuais e futuros, simulações hidrológicas foram realizadas com o modelo SWAP, parametrizado para uma microbacia de 12 km2, inserida em área de Caatinga preservada. A validação das simulações foi processada a partir de medidas diárias do conteúdo de água do solo na profundidade de 0,2 m no período de 2004 a 2012. A capacidade do solo em fornecer água às plantas foi avaliada através da atualização de uma função de potencial de fluxo matricial, que acopla as propriedades hidráulicas do solo, densidade de comprimento radicular e transpiração das plantas, aplicada a um grupo de solos da zona climática semiárida e sub-úmida. Como resultados principais destacam-se: nas condições climáticas atuais, o bioma Caatinga retorna 75% da precipitação anual para a atmosfera como evapotranspiração, particionada entre seus componentes (transpiração, evaporação e intercepção) em 41%, 40% e 19%, respectivamente. Evapotranspiração e temperatura do ar foram sensíveis à umidade do solo durante os períodos de junho-setembro e dezembro-janeiro. Em relação ao cenário climático futuro, a taxa de transpiração foi acrescida em 36%. A evaporação do solo e a interceptação foram reduzidas em 16% e 34%, respectivamente. A quantidade de precipitação devolvida para a atmosfera foi em média 98%. Para ambos os cenários climáticos, é sugerido que os fluxos de água no sistema solo-planta-atmosfera são controlados pela camada superior do solo (0-0,2 m), fornecendo, em média, 80% do total transpirado, indicando que, caso os cenários de disponibilidade hídrica reduzida se confirmem, o bioma Caatinga pode se tornar completamente dependente dos pulsos de água no solo. A partir do potencial de fluxo matricial limitante revelou-se que os solos da região semiárida são capazes de manter o fluxo de água às plantas em taxas potenciais em condições de solo seco (potencial matricial limitante variando de -36 a -148 m), enquanto que, os solos da região mais úmida indicaram severa restrição hidráulica, com potencial matricial limitante maior do que -1,5 m. Ainda para os solos analisados, a atribuição de potencial na superfície da raiz inferior a -150 m não ocasionou aumento de disponibilidade hídrica, indicando que valores menores que -150 m não implicam em uma estratégia viável para suportar baixa disponibilidade hídrica.

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