Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Ordenar por: RelevânciaAutorTítuloAnoImprime registros no formato resumido
Registros recuperados: 164
Primeira ... 123456789 ... Última
Imagem não selecionada

Imprime registro no formato completo
Waterboatmen, and testing for Lotka-Volterra-type interactions OMA
Bergmans, M..
A previous paper by Istock, in which this author claims to have successfully applied the Lotka-Volterra model to his observations on corixid population dynamics, is criticised for the shortcomings in evidence cited to support the model's fit with the data. It is contended that the dynamic behaviour of the system of Hesperocorixa lobata - Sigara macropala interaction is not in accordance with the Lotka-Volterra model. ThIs brief critique is followed by comments by istock in reply to the points raised in Bergmans' letter.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Models; Population dynamics; Corixidae.
Ano: 1979 URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3600
Imagem não selecionada

Imprime registro no formato completo
A laboratory model system for analysing microbial interactions occurring in anoxic estuarine sediments. ArchiMer
Herbert, R; Keith, S.
Defined mixed populations of Clostridium butyricum, Desulfovibrio desulfuricans and Chromatium vinosum co-existed for long periods when grown in a single stage chemostat with glucose as sole carbon source. The nature and availability of the inorganic nitrogen source exerted a major effect on carbon flow in the experimental system. The data show that both the C. butyricum and D. desulfuricans isolates can utilise NO sub(3) as an e super(-)acceptor with an increase in cell yield. Under these growth conditions the free S super(2-) levels were lower resulting in more stable mixed populations. In addition the data show that the C. butyricum produces more oxidised fermentation end-products (acetate) when NO sub(3) super(-) was available and more reduced products...
Tipo: Text Palavras-chave: Chromatium vinosum; Desulfovibrio desulfuricans; Clostridium butyricum; Biogeochemistry; Models; Bacteria; Detritus; Mineralization; Anoxic sediments; Estuarine sedimentation; Analytical techniques; Carbon cycle; Interspecific relationships; Microbiology.
Ano: 1984 URL: http://archimer.ifremer.fr/doc/1984/acte-947.pdf
Imagem não selecionada

Imprime registro no formato completo
Front Materials AgEcon
Front Cover, Title Page, Foreword, Contents Page
Tipo: Conference Paper or Presentation Palavras-chave: Agricultural trade; International trade; Macroeconomic linkages; Models; Policy modeling; Trade modeling; Teaching/Communication/Extension/Profession.
Ano: 1985 URL: http://purl.umn.edu/50646
Imagem não selecionada

Imprime registro no formato completo
Philippine rural cultivators in transition: operational reality and cognized models in agricultural decision making International Rice Research Institute
Sandoval, Virginia D. Nazarea.
338 p. : ill. maps. Thesis (Ph.D.) -- University of Kentucky
Tipo: Thesis Palavras-chave: Rice; Farmers; Decision making; Models; Rural areas; Philippines.
Ano: 1987 URL: http://hdl.handle.net/123456789/1268
Imagem não selecionada

Imprime registro no formato completo
Approche de la capacité trophique d'un écosystème conchylicole ArchiMer
Heral, Maurice; Deslous-paoli, Jean-marc; Prou, Jean.
After a short bibliographical study of the different approaches for determination of the trophic capacity of a bay for molluscs culture, the authors, with a global mode, show the relations between the growth performance of the oysters Crassostrea gigas in relation with the cultivated stocks. The volumes of consumed and assimilated food are calculated for the stocks in relation with the incoming volumes of water in the bay and the residence time for neap tide and spring tide. The authors find a decrease of growth rate in relation with the volume of consumed food. When it is above 60% and when the volume of assimilated food is above 20%, there is a large decrease of the growth of oysters.
Tipo: Text Palavras-chave: Crassostrea gigas; Oysters; Stock assessment; Models; Food consumption; Growth; Biomass; Stock cultivé; Biomasse; Croissance; Modèle; Crassostrea gigas; Huîtres; Capacité trophique.
Ano: 1988 URL: http://archimer.ifremer.fr/doc/1988/acte-3834.PDF
Imagem não selecionada

Imprime registro no formato completo
On physical remodeling and institution strengthening: an evaluation of the implications of the pilot field channel experience for the rehabilitation project at Uda Walawe, Sri Lanka AgEcon
Merrey, Douglas J.; Jinapala, Kiribandage.
This paper is a substantially revised version of a draft paper previously circulated to some officials in Sri Lanka. The title of that paper was "Testing a New Field Channel Design: A Pilot Project of the Uda Walawe Rehabilitation Project, Sri Lanka. It was reviewed by the International Irrigation Management Institute (IIMI) - Sri Lanka Consultative" Consultative Committee at its January 1988 meeting; as the minutes of that meeting indicate, the Committee members recognized- the significance of the main findings of the draft report, and agreed that physical rehabilitation by itself could be counter productive unless supported by proper institutional changes. The paper is based on periodic observations (approximately weekly) of farmers' use of a...
Tipo: Working or Discussion Paper Palavras-chave: Institution building; Rehabilitation; Models; Irrigation design; Farm Management; Institutional and Behavioral Economics.
Ano: 1988 URL: http://purl.umn.edu/114045
Imagem não selecionada

Imprime registro no formato completo
Les modèles bio-économiques en halieutique : démarches et limites ArchiMer
Gilly, Bernard.
The bio-economic models in fishing : approaches and limits Bio-economic modelling technics for jisheries have been developed from the late jïfties. They are currently based on neo-classic economic therory. Their use has led to strong theoretical development in the Jield ofjsheries management, but they are utterly lacking qf pratical sense because the basic assumptions are not sujjïciently close to the reality. The main types of models are presented (statie and dynamic. determinist and random, simulation and optimisation) and their bounds are discussed.
Tipo: Text Palavras-chave: Management; Models; Bio economy; Fisheries; SEM; Aménagement; Modéles; Bio économie; Pêcheries.
Ano: 1989 URL: http://archimer.ifremer.fr/doc/1989/publication-2517.pdf
Imagem não selecionada

Imprime registro no formato completo
Modelisation de la coherence spatiale du bruit genere par les vagues ArchiMer
Plaisant, M.
Empirical models already exist for ambient noise spectral density function of frequency, sea state or wind speed but they give no information on the spatial structure or coherence of the noise field which is essential as soon as array beamforming is involved. We have developed a model which computes the spatial coherence matrix of the noise field due to a continuous distribution of sources located at the sea surface, and also the noise power spectral density after classical beamforming on an equidistant hydrophones linear array. In this model, propagation effects like rays bending due to variations of index of refraction and multiple bottom and surface reflections are taken into account. Principles of the modeling are presented and results demonstrate that...
Tipo: Text Palavras-chave: Spectral analysis; Models; Wind speed; Sea surface; Surface water waves; Acoustic equipment; Sound waves; Underwater noise; Ambient noise.
Ano: 1990 URL: http://archimer.ifremer.fr/doc/1990/acte-1143.pdf
Imagem não selecionada

Imprime registro no formato completo
Alternative methods and models for analyzing the impact of mechanization-- a case study of selected rice growing household in North China International Rice Research Institute
Sun, Haoxun.
102 l. : ill. Thesis (M.S.) -- University of the Philippines at Los Banos
Tipo: Thesis Palavras-chave: Rice; Agricultural machinery and equipment; Mechanization; Economic impact; Models; Households; China.
Ano: 1990 URL: http://hdl.handle.net/123456789/978
Imagem não selecionada

Imprime registro no formato completo
Rice blast modeling and forecasting: selected papers from the International Rice Research Conference, 27-31 August 1990, Seoul, Korea. International Rice Research Institute
International Rice Research Conference (1990 : Seoul, Korea).; International Rice Research Institute.; Korea. Rural Development Administration..
99 p. : ill.
Tipo: Book Palavras-chave: Blast; Forecasting; Models.
Ano: 1991 URL: http://hdl.handle.net/123456789/679
Imagem não selecionada

Imprime registro no formato completo
Why carrying capacity models are useful tools for management of bivalve molluscs culture ArchiMer
Heral, Maurice.
In areas where oyster or mussel culture is very intensive, declines of growth rate and decreases of survival rate have occurred. For these reasons, plans have been proposed to regulate the cultivated biomasses in order to fit the carrying capacity of the different ecosystems (Heral et al 1990; Heral, 1991). In areas where new aquaculture of molluscs is beginning, oyster or mussel farmers need to know how large the extension of the culture could be and what the maximal densities should be in order to obtain the maximum economic benefit. Furthermore, as mollusc cultures are developed in coastal areas, they are very susceptible to changes in environmental conditions that can modify trophic relationships, or directly reduce growth rate, physiological...
Tipo: Text Palavras-chave: Oyster model; Analytical model; Bivalve molluscs culture; Models.
Ano: 1993 URL: http://archimer.ifremer.fr/doc/1993/publication-6104.PDF
Imagem não selecionada

Imprime registro no formato completo
Wheat supply response in Nepal: econometric and programming approaches International Rice Research Institute
Bhattarai, Madhusudan.
165 leaves : ill. Thesis (M.S.) -- University of the Philippines at Los Baños
Tipo: Thesis Palavras-chave: Wheat; Supply; Models; Prices; Rice; Economic analysis; Nepal.
Ano: 1994 URL: http://hdl.handle.net/123456789/698
Imagem não selecionada

Imprime registro no formato completo
Integrated water resource systems: Theory and policy implications AgEcon
Keller, Andrew; Keller, Jack; Seckler, David.
Presents the concept of integrated water resources systems (IWS) as clearly and simply as possible, with a focus on the irrigation sector-the largest and most complex user of water.
Tipo: Report Palavras-chave: Water resource management; Water policy; Irrigation efficiency; Water demand; Leaching; Water use efficiency; Water supply; Evapotranspiration; Models; Water conservation; Crop Production/Industries; Farm Management; Land Economics/Use; Research and Development/Tech Change/Emerging Technologies.
Ano: 1996 URL: http://purl.umn.edu/52730
Imagem não selecionada

Imprime registro no formato completo
A Comparison of Timber Models for Use in Public Policy Analysis AgEcon
Sohngen, Brent; Sedjo, Roger A..
In this paper, we compare and contrast two types of timber models that have been used for public policy analysis. These models have been variously used to predict price, inventory and market welfare impacts under different exogenous forces that impact timber markets. The framework and theory for each model type is presented and discussed. We then thoroughly test the two model types across six potential exogenous shocks to timber markets, ranging from instantaneous demand shocks to gradual supply adjustments. Our comparison indicates that these models predict potentially important differences in timber market behavior. These differences are important to consider for those who do public policy analysis.
Tipo: Working or Discussion Paper Palavras-chave: Timber markets; Models; Dynamic adjustment; Optimization; Resource /Energy Economics and Policy; C62; Q21; Q23.
Ano: 1996 URL: http://purl.umn.edu/10467
Imagem não selecionada

Imprime registro no formato completo
Uncertainty, Climate Change, and Adaptive Management Ecology and Society
Peterson, Garry; McGill University; garry.peterson@mcgill.ca; De Leo, Giulio A; Agenzia Regionale per la Protezione dell' Ambiente; deleo@dsa.unipr.it; Hellmann, Jessica J; Stanford University; jessicah@leland.stanford.edu; Janssen, Marco A; Indiana University; maajanss@indiana.edu; Kinzig, Ann; Arizona State University; Ann.Kinzig@asu.edu; Malcolm, Jay R; University of Toronto; jay.malcolm@utoronto.ca; O'Brien, Karen L; -; kobrien@online.no; Pope, Shealagh E; Environment Canada; shealagh.pope@ec.gc.ca; Rothman, Dale S; Columbia University; drothman@bio2.edu; Shevliakova, Elena; Carnegie Mellon University; lenish@cmu.edu; Tinch, Robert R.T.; York University, UK; rrtt100@york.ac.uk.
Tipo: Peer-Reviewed Reports Palavras-chave: Adaptive management; Climate change; Global change; Uncertainty; Models.
Ano: 1997
Imagem não selecionada

Imprime registro no formato completo
Utilizacao de injetores tipo Venture duplo visando ampliar seu limite operacional e uso na quimigacao em condicoes de media e de alta pressao. Repositório Alice
FEITOSA FILHO, J. C.; BOTREL, T. A.; PINTO, J. M..
Um experimento foi instalado no Laboratorio de Hidraulica da Escola Superior de Agricultura Luiz de Queiroz-USP/SP visando avaliar o desempenho da instalacao que utiliza dois injetores tipo Venturi e seu uso em condicoes de media e alta pressao. Testou-se um sistema com pares de injetores de 40 mm x 25 mm cujos dados foram comparados com os do injetor de 25 mm instalado em serie. Avaliou-se as pressoes de servico, os diferenciais de pressao, as vazoes motrizes, as vazoes succionadas, as perdas de carga e os rendimentos. Comprovou-se um aumento no limite operacional dos injetores nesse tipo de instalacao principalmente nas pressoes de servico mais elevadas. Houve maior influencia no desempenho e nas vazoes succionadas devido ao diferencial de pressao...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Quimigacao; Injetor Venturi; Uso; Desempenho; Modelo; Equipamento performance; Venturi injector; Use; Fertirrigação; Irrigação; Equipment performance; Fertigation; Models.
Ano: 1998 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/132034
Imagem não selecionada

Imprime registro no formato completo
Water-resource and land-use issues AgEcon
Calder, Ian R..
This paper reviews perceived notions of the relationships between catchment land use and hydrology and explores whether much of the widely disseminated folklore, so often inextricably linked with issues of land use, is based on myth or reality. Gaps in our knowledge of the underlying processes in relation to land use and hydrology are identified. Our ability to apply this knowledge at different scales ranging from the plot to the catchment and regional scales are discussed and specific examples are drawn from Indian and African case studies. Methods for linking spatially distributed land-use hydrological models with economics and ecology through decision support systems are outlined and proposed as a framework for the integrated management of land and...
Tipo: Book Palavras-chave: Water resource management; Water use; Case studies; Catchment areas; Land use; Hydrology; Models; Evaporation; Soil moisture; Decision support tools; Runoff; Flow; Forestry; Deforestation; Erosion; Rain; Environmental Economics and Policy; Land Economics/Use.
Ano: 1998 URL: http://purl.umn.edu/113610
Imagem não selecionada

Imprime registro no formato completo
Impact assessment of rehabilitation intervention in the Gal Oya Left Bank AgEcon
Amarasinghe, Upali A.; Sakthivadivel, Ramasamy; Murray-Rust, Hammond.
Assesses the impact of rehabilitation interventions on irrigation system performance using time series analysis. The study demonstrates that with proper impact specification and model identification, the nature and magnitude of the impacts of different interventions can be separated from the effects of simultaneous changes in dominant exogenous factors.
Tipo: Report Palavras-chave: Irrigation management; Water management; Irrigation systems; Productivity; Rehabilitation; Models; Project evaluation; Rain; Reservoir storage; Sri Lanka; Gal Oya Project; Community/Rural/Urban Development; Crop Production/Industries; Farm Management; Productivity Analysis; Resource /Energy Economics and Policy.
Ano: 1998 URL: http://purl.umn.edu/52965
Imagem não selecionada

Imprime registro no formato completo
Акватория и берега Севастополя: экосистемные процессы и услуги обществу IBSS Repository
Шадрин, Н. В.; Павлова, Е. В..
В монографии представлены результаты изучения современной экологической ситуации в акватории Севастополя. Рассмотрены также вопросы взаимосвязей функционирования экосистем и социально-экономического развития. Для экологов, экономистов, менеджеров, студентов и жителей Севастополя.
Tipo: Book Palavras-chave: Ecosystems; Scales; Models; Anthropogenic factors; Eutrophication; Ichthyoplankton; Phytoplankton; Zooplankton; Oil pollution; Litter; Mortality; Coastal zone; Biodiversity; Rivers; Zooplankton; Ecosystems; Scales; Models; Eutrophication; Rivers; Biodiversity; Phytoplankton; Anthropogenic factors; Mortality; Http://aims.fao.org/aos/agrovoc/c_15490; Http://aims.fao.org/aos/agrovoc/c_2482; Http://aims.fao.org/aos/agrovoc/c_6838; Http://aims.fao.org/aos/agrovoc/c_4881; Http://aims.fao.org/aos/agrovoc/c_2734; Http://aims.fao.org/aos/agrovoc/c_6617; Http://aims.fao.org/aos/agrovoc/c_33949; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_34996; Http://aims.fao.org/aos/agrovoc/c_4945.
Ano: 1999 URL: http://repository.ibss.org.ua/dspace/handle/99011/381
Imagem não selecionada

Imprime registro no formato completo
Assessment of participatory management of irrigation schemes in Sri Lanka: Partial reforms, partial benefits AgEcon
Samad, Madar; Vermillion, Douglas Lynn.
Describes the application of a standard methodology developed by IWMI to assess the impact of irrigation management transfer on the performance of irrigation schemes. Includes detailed analysis of the effects of participatory management on the performance of irrigation schemes in Sri Lanka.
Tipo: Report Palavras-chave: Privatization; Policy; Performance evaluation; Indicators; Operating costs; Irrigation management; Economic aspects; Returns; Participatory management; Farmer participation; Government managed irrigation systems; Small scale systems; Large-scale systems; Regression analysis; Models; Agribusiness; Agricultural Finance; Community/Rural/Urban Development; Farm Management; Research and Development/Tech Change/Emerging Technologies.
Ano: 1999 URL: http://purl.umn.edu/44577
Registros recuperados: 164
Primeira ... 123456789 ... Última
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional