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1.
Arq. bras. med. vet. zootec. (Online) ; 73(5): 1159-1170, Sept.-Oct. 2021. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1345261

ABSTRACT

The article considers econometric ridge regression models of the risk-sensitive sunflower yield on the example of an export-oriented agricultural crop. In particular, we have proved that despite the functional mulcollinearity of the predictors in the sunflower yield model with respect to risk caused by the algorithm peculiarities of the hierarchy analysis methods, the ridge regression procedure makes it possible to obtain its complete specification and provide biased but stable estimates of the forecast parameters in the case of uncertain input variables. It has been substantiated that the rational value of the displacement parameters is expedient to be established using a graphical interpretation of the ridge wake as the border of fast and slow fluctuations in the estimates of the ridge regression coefficients. Econometric models were calculated using SPSS Statistics, Mathcad and FAR-AREA 4.0 software. The empirical basis for forecast calculations was the assessment of trends in sunflower production in all categories of farms in the Rostov region of Russia for the period of 2008-2018. The calculation results of econometric models made it possible to develop three author's scenarios for the sunflower production in the region, namely, inertial, moderate, and optimistic ones that consider the export-oriented strategy of the agro-industrial complex.(AU)


O artigo considera modelos econométricos de regressão de rendimento de girassol sensível ao risco sobre o exemplo de uma cultura agrícola orientada para a exportação. Em particular, provamos que apesar da multicolinearidade funcional dos preditores no modelo de rendimento de girassol com relação ao risco causado pelas peculiaridades dos algoritmos dos métodos de análise hierárquica, o procedimento de regressão de cristas permite obter sua especificação completa e fornecer estimativas tendenciosas, mas estáveis dos parâmetros de previsão no caso de variáveis de entrada incertas. Foi comprovado que o valor racional dos parâmetros de deslocamento é conveniente de ser estabelecido usando uma interpretação gráfica da esteira da crista como fronteira das flutuações rápidas e lentas nas estimativas dos coeficientes de regressão da crista. Os modelos econométricos foram calculados usando o software SPSS Statistics, Mathcad e FAR-AREA 4.0. A base empírica para os cálculos de previsão foi a avaliação das tendências da produção de girassol em todas as categorias de fazendas na região de Rostov na Rússia para o período de 2008-2018. Os resultados dos cálculos dos modelos econométricos permitiram desenvolver três cenários de autor para a produção de girassol na região, a saber, os cenários inercial, moderado e otimista que consideram a estratégia orientada à exportação do complexo agroindustrial.(AU)


Subject(s)
Models, Econometric , Crops, Agricultural/supply & distribution , Crop Production/economics , Forecasting , Helianthus , Exportation of Products
2.
Int J Public Health ; 65(7): 1087-1096, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32712693

ABSTRACT

OBJECTIVES: To evaluate how the food systems in areas close to sugarcane monocrops influence the prevalence of food insecurity (FI) among three ethnic communities in the upper Cauca River basin of Colombia. METHODS: We developed a mixed methodology study at three rural zones located in the departments of Cauca and Valle del Cauca, Colombia, using a household survey to establish the level of FI, and semi-structured interviews with key community actors. RESULTS: These three ethnic communities have a high prevalence of FI (> 70%) that was found to be associated with economic income, social security, gender, the presence of minors in the home, refrigerator in operation and ownership of the land. Loss of food sovereignty was associated with the sale and rental of land. CONCLUSIONS: The sugarcane monocrop has contributed to environmental crises, spatial confinement and sociocultural disruption in ethnic territories; by renting, selling or leasing their land to the industrial production of sugarcane, traditional practices of food production and self-consumption have been profoundly transformed. Ethnic cultures are endangered, while food security and sovereignty of indigenous and black communities have been negatively affected.


Subject(s)
Agriculture/statistics & numerical data , Crops, Agricultural/supply & distribution , Ethnicity/statistics & numerical data , Farms/statistics & numerical data , Food Insecurity , Food Supply/statistics & numerical data , Rural Population/statistics & numerical data , Adult , Aged , Aged, 80 and over , Colombia/epidemiology , Female , Humans , Male , Middle Aged , Prevalence , Saccharum , Socioeconomic Factors
3.
Nature ; 579(7799): 393-396, 2020 03.
Article in English | MEDLINE | ID: mdl-32188954

ABSTRACT

Agricultural practices constitute both the greatest cause of biodiversity loss and the greatest opportunity for conservation1,2, given the shrinking scope of protected areas in many regions. Recent studies have documented the high levels of biodiversity-across many taxa and biomes-that agricultural landscapes can support over the short term1,3,4. However, little is known about the long-term effects of alternative agricultural practices on ecological communities4,5 Here we document changes in bird communities in intensive-agriculture, diversified-agriculture and natural-forest habitats in 4 regions of Costa Rica over a period of 18 years. Long-term directional shifts in bird communities were evident in intensive- and diversified-agricultural habitats, but were strongest in intensive-agricultural habitats, where the number of endemic and International Union for Conservation of Nature (IUCN) Red List species fell over time. All major guilds, including those involved in pest control, pollination and seed dispersal, were affected. Bird communities in intensive-agricultural habitats proved more susceptible to changes in climate, with hotter and drier periods associated with greater changes in community composition in these settings. These findings demonstrate that diversified agriculture can help to alleviate the long-term loss of biodiversity outside natural protected areas1.


Subject(s)
Agriculture/methods , Agriculture/statistics & numerical data , Biodiversity , Birds/classification , Forests , Animals , Cattle , Costa Rica , Crops, Agricultural/supply & distribution , Extinction, Biological , Forestry/statistics & numerical data , Global Warming/statistics & numerical data , Pest Control, Biological , Pollination , Seed Dispersal , Time Factors
4.
J Ethnobiol Ethnomed ; 15(1): 35, 2019 Jul 15.
Article in English | MEDLINE | ID: mdl-31307519

ABSTRACT

BACKGROUND: As concerns about agrodiversity loss and its impact on food security increase, interest in seed-saving practices and motivations has risen, especially in regions characterized by ancestral farming. Agroecology practitioners in the northern Andes of Ecuador (n = 65) participated in this study to describe (1) the dynamics of intergenerational agrodiversity, (2) perceptions of relevance of the crops they grow, (3) criteria for characterizing the differences between conventional and non-conventional seeds, and (4) their seed-saving practices. METHODS: This exploratory study incorporated a community-based participatory research approach using mixed methods. We conducted (1) a timeline mapping for exploring the dynamics of intergenerational agrodiversity and (2) structured interviews to explore the perception of relevance of crops grown to identify criteria for characterizing conventional and non-conventional seeds and for identifying seed-saving practices. We computed ranks and frequencies from free listing data derived from the interviews to detect the most salient patterns for crop diversity and seed-saving practices. A principal component analysis was performed to illustrate crops distribution within the study area. RESULTS AND DISCUSSION: Based on the timeline-mapping tool, we found that participants perceive an intergenerational loss of agrodiversity. Data derived from free listing determined that salient crops differ in each location of the study area, mostly due to geographic (altitude, climate), market factors, and crop management limitations. Responses from open-ended interview questions revealed that farmers discriminate conventional from non-conventional seeds using yield, adaptation to local conditions, pest tolerance, taste, and crop management as criteria. Analysis of free listing data determined that the most salient reported practices related to seed saving were soil fertility management, seed selection, safe seed storage, tilling and rowing, and weeding. CONCLUSIONS: This study contributes to raising awareness of intergenerational agrodiversity loss and replacement with modern crops. We found the relevance of crops and practices is subject to cultural and environmental context, and few agricultural practices are exclusively used for seed saving. Further, farmers clearly discriminate conventional from non-conventional seeds based on advantages and disadvantages, cultural motivation, and produce destination. The community-based participatory approach resulted in positive engagement from participants and promoted commitment from farmers to preserve agrodiversity and support practices at the community level.


Subject(s)
Agriculture/methods , Biodiversity , Crops, Agricultural/supply & distribution , Food Supply/statistics & numerical data , Intergenerational Relations , Climate , Developing Countries , Ecuador , Female , Humans , Interviews as Topic , Male , Rural Population
5.
Semina ciênc. agrar ; 37(5): 2881-2890, Sept.-Oct.2016. tab
Article in English | VETINDEX | ID: biblio-1500542

ABSTRACT

Predictive models of Asian soybean rust have been described by researchers to estimate favorable responses to epidemics. The prediction strategies are based on weather data obtained during period when initial symptoms of the disease are observed. Therefore, this study will evaluate the application of two prediction models of Asian soybean rust, and compare the results from two harvest seasons. The experiments were carried out during the 2011/2012 and 2012/2013 seasons in Londrina, PR. SIGA spore traps were installed to monitor the presence of Phakopsora pachyrhizi uredospores, and Electronic trees, to collect data on weather variables. Following the detection of the first urediniospores, incidence and disease severity were assessed and compared with the predictions made by the models. The model described by Reis et al. (2004) did not indicate conditions favorable for the development of the first rust lesions following the detection of the first urediniospores during the 2011/2012 season. The premonitory symptoms of rust in the first and second harvest seasons were observed only when the model of Reis et al. (2004) indicated SDVPI close to 15 units. The model of Del Ponte et al. (2006b) overestimated the final rust severity during the two seasons.


Modelos de previsão da ferrugem asiática da soja foram descritos por pesquisadores para estimar a favorabilidade climática para a ocorrência de epidemias. As estratégias de previsão estão fundamentadas em dados meteorológicos, a partir dos sintomas iniciais da doença. Portanto, objetivou-se aplicar dois modelos de previsão da ferrugem asiática da soja, e comparar com os resultados de duas safras agrícolas. A condução dos experimentos ocorreu nas safras 2011/2012 e 2012/2013 no município de Londrina, PR. Foram instalados Coletores de esporos SIGA para monitorar a presença de uredósporos de P. pachyrhizi, e Árvores Eletrônicas de Molhamento para coletar dados das variáveis meteorológicas. A partir da detecção dos primeiros uredósporos foram realizadas avaliações da incidência e da severidade da ferrugem, para comparar com as previsões feitas pelos modelos. O modelo de Reis et al. (2004) não indicou condições para o desenvolvimento das primeiras lesões da ferrugem após a chegada dos primeiros uredósporos na safra 2011/2012. Os primeiros sintomas da ferrugem na primeira e na segunda safra foram constatados apenas quando o modelo de Reis et al. (2004) indicou SVDPI próximo a 15 unidades. O modelo de Del Ponte et al. (2006b) superestimou a severidade final da ferrugem-asiática nas duas safras.


Subject(s)
Crops, Agricultural/growth & development , Crops, Agricultural/supply & distribution , Glycine max/chemistry
6.
Semina Ci. agr. ; 37(5): 2881-2890, Sept.-Oct.2016. tab
Article in English | VETINDEX | ID: vti-27701

ABSTRACT

Predictive models of Asian soybean rust have been described by researchers to estimate favorable responses to epidemics. The prediction strategies are based on weather data obtained during period when initial symptoms of the disease are observed. Therefore, this study will evaluate the application of two prediction models of Asian soybean rust, and compare the results from two harvest seasons. The experiments were carried out during the 2011/2012 and 2012/2013 seasons in Londrina, PR. SIGA spore traps were installed to monitor the presence of Phakopsora pachyrhizi uredospores, and Electronic trees, to collect data on weather variables. Following the detection of the first urediniospores, incidence and disease severity were assessed and compared with the predictions made by the models. The model described by Reis et al. (2004) did not indicate conditions favorable for the development of the first rust lesions following the detection of the first urediniospores during the 2011/2012 season. The premonitory symptoms of rust in the first and second harvest seasons were observed only when the model of Reis et al. (2004) indicated SDVPI close to 15 units. The model of Del Ponte et al. (2006b) overestimated the final rust severity during the two seasons.(AU)


Modelos de previsão da ferrugem asiática da soja foram descritos por pesquisadores para estimar a favorabilidade climática para a ocorrência de epidemias. As estratégias de previsão estão fundamentadas em dados meteorológicos, a partir dos sintomas iniciais da doença. Portanto, objetivou-se aplicar dois modelos de previsão da ferrugem asiática da soja, e comparar com os resultados de duas safras agrícolas. A condução dos experimentos ocorreu nas safras 2011/2012 e 2012/2013 no município de Londrina, PR. Foram instalados Coletores de esporos SIGA para monitorar a presença de uredósporos de P. pachyrhizi, e Árvores Eletrônicas de Molhamento para coletar dados das variáveis meteorológicas. A partir da detecção dos primeiros uredósporos foram realizadas avaliações da incidência e da severidade da ferrugem, para comparar com as previsões feitas pelos modelos. O modelo de Reis et al. (2004) não indicou condições para o desenvolvimento das primeiras lesões da ferrugem após a chegada dos primeiros uredósporos na safra 2011/2012. Os primeiros sintomas da ferrugem na primeira e na segunda safra foram constatados apenas quando o modelo de Reis et al. (2004) indicou SVDPI próximo a 15 unidades. O modelo de Del Ponte et al. (2006b) superestimou a severidade final da ferrugem-asiática nas duas safras.(AU)


Subject(s)
Glycine max/chemistry , Crops, Agricultural/growth & development , Crops, Agricultural/supply & distribution
7.
Genet Mol Res ; 13(3): 5221-40, 2014 Jul 07.
Article in English | MEDLINE | ID: mdl-25061747

ABSTRACT

In Brazil, the first genetically modified (GM) crop was released in 1998, and it is estimated that 84, 78, and 50% of crop areas containing soybean, corn, and cotton, respectively, were transgenic in 2012. This intense and rapid adoption rate confirms that the choice to use technology has been the main factor in developing national agriculture. Thus, this review focuses on understanding these dynamics in the context of farmers, trade relations, and legislation. To accomplish this goal, a survey was conducted using the database of the National Cultivar Registry and the National Service for Plant Variety Protection of the Ministry of Agriculture, Livestock and Supply [Ministério da Agricultura, Pecuária e Abastecimento (MAPA)] between 1998 and October 13, 2013. To date, 36 events have been released: five for soybeans, 18 for corn, 12 for cotton, and one for beans. From these events, 1395 cultivars have been developed and registered: 582 for soybean, 783 for corn and 30 for cotton. Monsanto owns 73.05% of the technologies used to develop these cultivars, while the Dow AgroScience - DuPont partnership and Syngenta have 16.34 and 4.37% ownership, respectively. Thus, the provision of transgenic seeds by these companies is an oligopoly supported by legislation. Moreover, there has been a rapid replacement of conventional crops by GM crops, whose technologies belong almost exclusively to four multinational companies, with the major ownership by Monsanto. These results reflect a warning to the government of the increased dependence on multinational corporations for key agricultural commodities.


Subject(s)
Agriculture/legislation & jurisprudence , Crops, Agricultural/supply & distribution , Plants, Genetically Modified , Agriculture/economics , Agriculture/ethics , Brazil , Crops, Agricultural/economics , Crops, Agricultural/genetics , Crops, Agricultural/growth & development , Gossypium/genetics , Gossypium/growth & development , Humans , Glycine max/genetics , Glycine max/growth & development , Glycine max/supply & distribution , Transgenes , Zea mays/genetics , Zea mays/growth & development , Zea mays/supply & distribution
8.
Nat Commun ; 5: 3858, 2014 May 13.
Article in English | MEDLINE | ID: mdl-24819889

ABSTRACT

Reactive nitrogen (Nr) is an indispensable nutrient for agricultural production and human alimentation. Simultaneously, agriculture is the largest contributor to Nr pollution, causing severe damages to human health and ecosystem services. The trade-off between food availability and Nr pollution can be attenuated by several key mitigation options, including Nr efficiency improvements in crop and animal production systems, food waste reduction in households and lower consumption of Nr-intensive animal products. However, their quantitative mitigation potential remains unclear, especially under the added pressure of population growth and changes in food consumption. Here we show by model simulations, that under baseline conditions, Nr pollution in 2050 can be expected to rise to 102-156% of the 2010 value. Only under ambitious mitigation, does pollution possibly decrease to 36-76% of the 2010 value. Air, water and atmospheric Nr pollution go far beyond critical environmental thresholds without mitigation actions. Even under ambitious mitigation, the risk remains that thresholds are exceeded.


Subject(s)
Crops, Agricultural/supply & distribution , Environmental Pollution/prevention & control , Food Supply , Population Growth , Reactive Nitrogen Species/supply & distribution , Animals , Crops, Agricultural/metabolism , Humans , Models, Theoretical , Nitrogen Fixation
9.
Am J Bot ; 101(4): 624-36, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24688056

ABSTRACT

PREMISE OF THE STUDY: People retain culinary customs when they migrate. We tested this commitment via the study of Puerto Rican fresh produce markets in the continental United States over time, 18 yr, and space, by comparisons with source markets in Puerto Rico (PR). METHODS: A survey of Puerto Rican markets in Hartford (HT), Connecticut in 1993-1994 was repeated in 2009-2010. A comparative study was made at open-air markets in PR in 2009. Surveys recorded fresh crops, and interviews with vendors and Hartford Puerto Rican residents provided context. KEY RESULTS: We recorded 84 plant crops (64 species; 32 families) for seven categories. The largest category was viandas (fresh, starchy "root" crops and immature fruits), followed by saborizantes (flavorings). In the second HT survey, 80% of the crops were still present. And ∼90% of the HT 1993-1994 crops and ∼75% of the HT 2009-2010 crops were shared with markets in PR. CONCLUSIONS: On the basis of our results, we suggest two new concepts. The persistence of these largely tropical foods in a temperate market far removed from tropical PR shows the importance of basic foods as an element of cultural identification. We recognize this stability as an example of "culinary cultural conservation". Second, analysis of these fresh produce markets leads to the conclusion that viandas are the most prominent in diversity, persistence over time and distance, volume, and in terms of consumers' "willingness to pay". Accordingly, we consider the viandas a good example of a "cultural keystone food group", a food group that is emblematic of a community's culinary conservation.


Subject(s)
Crops, Agricultural/classification , Cultural Characteristics , Feeding Behavior/ethnology , Connecticut , Crops, Agricultural/economics , Crops, Agricultural/supply & distribution , Puerto Rico/ethnology , Time Factors
11.
Curr Biol ; 18(20): 1572-5, 2008 Oct 28.
Article in English | MEDLINE | ID: mdl-18926704

ABSTRACT

There is evidence that pollinators are declining as a result of local and global environmental degradation [1-4]. Because a sizable proportion of the human diet depends directly or indirectly on animal pollination [5], the issue of how decreases in pollinator stocks could affect global crop production is of paramount importance [6-8]. Using the extensive FAO data set [9], we compared 45 year series (1961-2006) in yield, and total production and cultivated area of pollinator-dependent and nondependent crops [5]. We investigated temporal trends separately for the developed and developing world because differences in agricultural intensification, and socioeconomic and environmental conditions might affect yield and pollinators [10-13]. Since 1961, crop yield (Mt/ha) has increased consistently at average annual growth rates of approximately 1.5%. Temporal trends were similar between pollinator-dependent and nondependent crops in both the developed and developing world, thus not supporting the view that pollinator shortages are affecting crop yield at the global scale. We further report, however, that agriculture has become more pollinator dependent because of a disproportionate increase in the area cultivated with pollinator-dependent crops. If the trend toward favoring cultivation of pollinator-dependent crops continues, the need for the service provided by declining pollinators will greatly increase in the near future.


Subject(s)
Agriculture/trends , Crops, Agricultural/supply & distribution , Ecosystem , Pollination , Agriculture/economics , Animals , Bees/physiology , Conservation of Natural Resources/economics , Crops, Agricultural/economics , Food Supply/economics
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