Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros

Métodos Terapéuticos y Terapias MTCI
Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Nature ; 618(7964): 316-321, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37225981

RESUMEN

In the United Nations Decade on Ecosystem Restoration1, large knowledge gaps persist on how to increase biodiversity and ecosystem functioning in cash crop-dominated tropical landscapes2. Here, we present findings from a large-scale, 5-year ecosystem restoration experiment in an oil palm landscape enriched with 52 tree islands, encompassing assessments of ten indicators of biodiversity and 19 indicators of ecosystem functioning. Overall, indicators of biodiversity and ecosystem functioning, as well as multidiversity and ecosystem multifunctionality, were higher in tree islands compared to conventionally managed oil palm. Larger tree islands led to larger gains in multidiversity through changes in vegetation structure. Furthermore, tree enrichment did not decrease landscape-scale oil palm yield. Our results demonstrate that enriching oil palm-dominated landscapes with tree islands is a promising ecological restoration strategy, yet should not replace the protection of remaining forests.


Asunto(s)
Biodiversidad , Productos Agrícolas , Restauración y Remediación Ambiental , Aceite de Palma , Árboles , Bosques , Aceite de Palma/provisión & distribución , Árboles/fisiología , Agricultura/métodos , Naciones Unidas , Clima Tropical , Productos Agrícolas/provisión & distribución , Restauración y Remediación Ambiental/métodos
2.
J Ethnobiol Ethnomed ; 15(1): 35, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31307519

RESUMEN

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.


Asunto(s)
Agricultura/métodos , Biodiversidad , Productos Agrícolas/provisión & distribución , Abastecimiento de Alimentos/estadística & datos numéricos , Relaciones Intergeneracionales , Clima , Países en Desarrollo , Ecuador , Femenino , Humanos , Entrevistas como Asunto , Masculino , Población Rural
3.
PLoS One ; 13(8): e0198750, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30075032

RESUMEN

Based on chronological and archaeobotanical studies of 15 Neolithic and Bronze Age sites from the northern Chinese Loess Plateau and southern Inner Mongolia-the agro-pastoral zone of China-we document changes in the agricultural system over time. The results show that wheat and rice were not the major crops of the ancient agricultural systems in these areas, since their remains are rarely recovered, and that millet cultivation was dominant. Millet agriculture increased substantially from 3000 BC-2000 BC, and foxtail millet evidently comprised a high proportion of the cultivated crop plants during this period. In addition, as the human population increased from the Yangshao to the Longshan periods, the length and width of common millet seeds increased by 20-30%. This demonstrates the co-evolution of both plants and the human population in the region. Overall, our results reveal a complex agricultural-gardening system based on the cultivation of common millet, foxtail millet, soybeans and fruit trees, indicating a high food diversity and selectivity of the human population.


Asunto(s)
Agricultura/historia , Arqueología , Evolución Biológica , Productos Agrícolas , Clima Desértico , Animales , Huesos/química , Productos Agrícolas/clasificación , Productos Agrícolas/provisión & distribución , Historia Antigua , Actividades Humanas/historia , Humanos , Datación Radiométrica
4.
Food Res Int ; 104: 77-85, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29433786

RESUMEN

Orange-fleshed sweet potato (OFSP) is considered the single most successful example of biofortification of a staple crop, and presents a feasible option to address vitamin A deficiency. Though initially promoted as part of a crop-based approach focusing on production and consumption at household level, it evolved into small-scale commercial production, predominantly in Sub-Saharan Africa. This paper reviews OFSP initiatives in relation to the South African food environment and food supply systems, also identifying opportunities for scaling out OFSP in a situation where sweet potato is not eaten as a staple. Current per capita consumption of sweet potato is low; the focus is thus on increasing consumption of OFSP, rather than replacing cream-fleshed varieties. For the major OFSP variety, Bophelo, 66g consumption can be sufficient to meet the recommended daily allowance for 1-3year old children (300µRE vitamin A). Despite a national Vitamin A supplementation programme and fortified staple foods in South Africa, 43.6% of children under 5years of age were reported to be vitamin A deficient in 2012, indicating a stronger need to promote the consumption of Vitamin A-rich foods, such as OFSP. To increase availability of and access to OFSP, all aspects of the food supply system need to be considered, including agricultural production, trade, food transformation and food retail and provisioning. Currently, small-scale commercial OFSP producers in South Africa prefer to deliver their produce to local informal markets. To enter the formal market, small-scale producers often have difficulties to meet the high standards of the retailers' centralised procurement system in terms of food quality, quantity and safety. Large retailers may have the power to increase the demand of OFSP, not just by improving availability but also by developing marketing strategies to raise awareness of the health benefits of OFSP. However, currently the largest scope for scaling out is through a number of public sector programmes such as the National School Nutrition Programme, Community Nutrition and Development Centres, Small-holder Farmer programmes and Agriparks. Though the major approach is focused on unprocessed, boiled OFSP, there are unexploited opportunities for processing of OFSP. However, the nutritional quality of products should be a main consideration within the context of the co-existence of undernutrition, overnutrition and micronutrient deficiencies in the country.


Asunto(s)
Productos Agrícolas/provisión & distribución , Dieta Saludable , Abastecimiento de Alimentos , Ipomoea batatas , Estado Nutricional , Valor Nutritivo , Raíces de Plantas , Verduras/provisión & distribución , Deficiencia de Vitamina A/prevención & control , Vitamina A/administración & dosificación , Comercio , Productos Agrícolas/economía , Productos Agrícolas/crecimiento & desarrollo , Dieta Saludable/economía , Abastecimiento de Alimentos/economía , Humanos , Ipomoea batatas/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Factores Protectores , Ingesta Diaria Recomendada , Factores de Riesgo , Conducta de Reducción del Riesgo , Sudáfrica/epidemiología , Verduras/economía , Deficiencia de Vitamina A/economía , Deficiencia de Vitamina A/epidemiología , Deficiencia de Vitamina A/fisiopatología
5.
Sci Prog ; 98(Pt 4): 379-90, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26790176

RESUMEN

Population growth makes food production increase necessary; economic growth increases demand for animal products and livestock feed. As further increase of the cropland area is ecologically undesirable, it is necessary to increase crop yields; this requires, inter alia, more nitrogen and phosphorus fertiliser despite the environmental problems which this will exacerbate. It is probable that a satisfactory food supply and an environmentally benign agriculture worldwide cannot be achieved without reducing population to approximately three billion. The reduction could be achieved by 2200 if the total fertility rate--currently 2.5--declined to 1.5 as a world average by 2050, and remained at that level until 2200, but the probability of such a global fertility trajectory is close to zero. It will also be necessary to replace fossil energy by nuclear and renewable energy in order to stabilise atmospheric carbon dioxide concentration, but the phase-out cannot be completed until the 22nd century, when the atmospheric concentration will be approximately 50% above the 2015 level of 400 ppm.


Asunto(s)
Conservación de los Recursos Naturales/tendencias , Productos Agrícolas/provisión & distribución , Fertilizantes/provisión & distribución , Abastecimiento de Alimentos , Regulación de la Población/tendencias , Crecimiento Demográfico , Animales , Huella de Carbono , Productos Agrícolas/crecimiento & desarrollo , Humanos , Nitrógeno/provisión & distribución , Fósforo/provisión & distribución
6.
Am J Bot ; 101(4): 624-36, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24688056

RESUMEN

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.


Asunto(s)
Productos Agrícolas/clasificación , Características Culturales , Conducta Alimentaria/etnología , Connecticut , Productos Agrícolas/economía , Productos Agrícolas/provisión & distribución , Puerto Rico/etnología , Factores de Tiempo
9.
Malar J ; 6: 125, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17868471

RESUMEN

INTRODUCTION: This paper reviews recent trends in the production, supply and price of the active ingredients as well as finished ACT products. Production and cost data provided in this paper are based on an ongoing project (Artepal). Stability data are derived from a development project on rectal artesunate. DISCUSSION: The artemisinin raw material and its derivatives appear to be very stable compared to the finished products. Supply of artemisinin changed in May 2004 when the Global Fund shifted financial support to qualified countries from chloroquine or sulphadoxine-pyrimethamine to an ACT for treatment of malaria. First, there was a sudden shortage of the starting material, and short term scarcity led to a steep rise in API price: it increased dramatically in 2004, from $350 per kg to more than $1000. Second, there was a parallel increase in the number of companies extracting artemisinin from 10 to 80 between 2003 and 2005 in China, and from 3 to 20 in Vietnam. Commercial cultivation began also in East Africa and Madagascar.A steady and predictable demand for the crop can eliminate such wide fluctuations and indirectly contribute to price stability of the herb, the API and ACT. With appropriate mechanisms to reduce those fluctuations, the cost of artemisinin might decrease sustainably to US$ 250-300 per kg. CONCLUSION: Today the global health community is facing the risk of another cyclical swing with lower demand feeding into reduced planting of A. annua and, thereafter, a new shortage of the raw material and higher API prices. International donors, the largest purchasers for ACTs could better coordinate their activities, in order to guarantee purchase of ACTs and consequently of API with manufacturers. In parallel, the base of quality producers of APIs and finished ACT products needs to be broadened.While the ACT programme is still in its early stages, the consequences of another wave of artemisinin and ACT shortages would permanently discredit it and impede any progress in rolling malaria back.


Asunto(s)
Antimaníacos/provisión & distribución , Artemisia annua/crecimiento & desarrollo , Artemisininas/provisión & distribución , Extractos Vegetales/provisión & distribución , Antimaníacos/economía , Artemisininas/economía , Productos Agrícolas/economía , Productos Agrícolas/provisión & distribución , Industria Farmacéutica , Quimioterapia Combinada , Control de Medicamentos y Narcóticos , Competencia Económica , Salud Global , Humanos , Malaria/tratamiento farmacológico , Extractos Vegetales/economía , Estudios Retrospectivos
10.
Philos Trans R Soc Lond B Biol Sci ; 360(1463): 2011-20, 2005 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-16433090

RESUMEN

Predictions of yield for the globe's major grain and legume arable crops suggest that, with a moderate temperature increase, production may increase in the temperate zone, but decline in the tropics. In total, global food supply may show little change. This security comes from inclusion of the direct effect of rising carbon dioxide (CO2) concentration, [CO2], which significantly stimulates yield by decreasing photorespiration in C3 crops and transpiration in all crops. Evidence for a large response to [CO2] is largely based on studies made within chambers at small scales, which would be considered unacceptable for standard agronomic trials of new cultivars or agrochemicals. Yet, predictions of the globe's future food security are based on such inadequate information. Free-Air Concentration Enrichment (FACE) technology now allows investigation of the effects of rising [CO2] and ozone on field crops under fully open-air conditions at an agronomic scale. Experiments with rice, wheat, maize and soybean show smaller increases in yield than anticipated from studies in chambers. Experiments with increased ozone show large yield losses (20%), which are not accounted for in projections of global food security. These findings suggest that current projections of global food security are overoptimistic. The fertilization effect of CO2 is less than that used in many models, while rising ozone will cause large yield losses in the Northern Hemisphere. Unfortunately, FACE studies have been limited in geographical extent and interactive effects of CO2, ozone and temperature have yet to be studied. Without more extensive study of the effects of these changes at an agronomic scale in the open air, our ever-more sophisticated models will continue to have feet of clay.


Asunto(s)
Aire , Dióxido de Carbono/metabolismo , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/metabolismo , Abastecimiento de Alimentos , Ozono/metabolismo , Aclimatación , Biomasa , Dióxido de Carbono/farmacología , Productos Agrícolas/fisiología , Productos Agrícolas/provisión & distribución , Grano Comestible , Predicción , Humanos , Ozono/farmacología , Fotosíntesis/efectos de los fármacos , Fotosíntesis/fisiología , Transpiración de Plantas/efectos de los fármacos , Transpiración de Plantas/fisiología , Valor Predictivo de las Pruebas
11.
Arch Tierernahr ; 56(2): 67-91, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12389223

RESUMEN

Consequences of the ban of meat and bone meal (MBM) and animal fat with regard to livestock feeding, cropping, ecology and economy where investigated with an inter-disciplinary approach for Germany and the European Union. Calculations were made for different production systems with pigs and poultry on the basis of statistical data for the production and for the feed markets as well as from requirement data for the respective species and production system. (1.) The ban of MBM from feeding caused a need for alternative protein sources. If all the amount of protein from MBM is to be replaced by soybean meal, in Germany and the EU about 0.30 and 2.30 x 10(6) t would be needed each year (supplementary amino acids not considered). Alternatively, doubling the grain legume acreage in Germany to about 420,000 ha would supply a similar amount of protein. A wider application of phase feeding with adjusted dietary amino acid concentrations, however, would allow for saving protein to an extent which is similar to the amount of protein that was contributed by MBM in recent years. Thus, the ban is a minor problem in terms of ensuring amino acid supply. (2.) However, alternative plant ingredients cannot compensate for the gap in P supply that is caused by the ban. An additional demand for inorganic feed phosphates of about 14,000 and 110,000 t per year is given in Germany and the EU, respectively. So far, this gap is filled almost completely by increased mining of rock phosphates. Alternatively, a general application of microbial phytase to all diets would largely fill this gap. Until the ban, MBM contributed to 57% of the supplementation of P that was needed for pigs and poultry. The ban of MBM makes large amounts of P irreversibly disappearing from the food chain. (3.) Energy from slaughter offal and cadavers can be utilized in different technologies, in the course of which the efficiency of energy utilisation depends on the technology applied. It is efficient in the cement work or rotation furnace if heat is the main energy required. In contrast, the energetic efficiency of fermentation is low. (4.) Incineration or co-incineration of MBM and other by-products causes pollution gas emissions amounting to about 1.4 kg CO2 and 0.2 kg NOx per kg. The CO2 production as such is hardly disadvantageous, because heat and electrical energy can be generated by the combustion process. The prevention of dangerous gaseous emissions from MBM burning is current standard in the incineration plants in Germany and does not affect the environment inadmissibly. (5.) The effects of the MBM ban on the price for compound feed is not very significant. Obviously, substitution possibilities between different feed ingredients helped to exchange MBM without large price distortions. However, with each kg MBM not used in pig and poultry feeding economic losses of about 0.14 [symbol: see text] have to considered. In conclusion, the by far highest proportion of raw materials for MBM comes as by-products from the slaughter process. Coming this way, and assuring that further treatment is safe from the hygienic point of view, MBM and animal fat can be regarded as valuable sources of amino acids, minerals and energy in feeding pigs and poultry. Using them as feedstuffs could considerably contribute to the goal of keeping limited nutrients, phosphorus in particular, within the nutrient cycle and dealing responsible with limited resources.


Asunto(s)
Aminoácidos/administración & dosificación , Alimentación Animal/normas , Fenómenos Fisiológicos Nutricionales de los Animales , Proteínas en la Dieta/administración & dosificación , Fósforo Dietético/administración & dosificación , Aminoácidos/provisión & distribución , Alimentación Animal/economía , Alimentación Animal/provisión & distribución , Crianza de Animales Domésticos/métodos , Animales , Productos Biológicos , Productos Agrícolas/provisión & distribución , Proteínas en la Dieta/provisión & distribución , Suplementos Dietéticos , Metabolismo Energético , Unión Europea , Fabaceae , Femenino , Alemania , Masculino , Eliminación de Residuos Sanitarios/métodos , Minerales/efectos adversos , Necesidades Nutricionales , Fósforo Dietético/provisión & distribución , Aves de Corral , Glycine max , Porcinos
12.
J Anim Sci ; 75(8): 2054-63, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9263051

RESUMEN

Annual nitrogen (N), phosphorus (P), and potassium (K) flows in agriculture in The Netherlands were identified and quantified in 1990, with special emphasis on pig production. Also, the effects that various management strategies in pig production have on NPK emission in 1990 were compared using a static deterministic simulation model. Ammonia emission from pig production in 1990 (60.9 Gg N) exceeded the defined target for the year 2000 (12.7 Gg N). Measures that affect volatilization of ammonia directly (i.e., introduction of low-emission stables, manure storage facilities, or manure application techniques) reduced ammonia emission most effectively. These measures, however, should be combined with a reduction in application of artificial N fertilizer to avoid an increase in N losses through leaching, run-off, or denitrification. Targets for ammonia emission in the year 2010 require a reduction in the pig population of 24 to 62%, in addition to implications of measures described in this article. National NPK losses in 1990 through leaching, run-off, or denitrification, predicted at 223.5 kg/ha for N, 32.7 kg/ha for P, and 67 kg/ha for K, exceeded government targets for the year 2010 (185 kg N/ha; 8.7 kg P/ha; norm not set for K). Reducing application of artificial NPK fertilizer reduced national NPK losses most effectively. For P, use of phytase and feeding pigs in accordance with their P requirements is required, in addition to limited use of artificial P fertilizer to meet targets for the year 2010. Hence, from an environmental point of view, pig production in The Netherlands is limited primarily by ammonia emission targets for the year 2010.


Asunto(s)
Alimentación Animal/provisión & distribución , Crianza de Animales Domésticos , Fenómenos Fisiológicos Nutricionales de los Animales , Productos Agrícolas/provisión & distribución , Porcinos/crecimiento & desarrollo , Amoníaco/análisis , Amoníaco/química , Amoníaco/provisión & distribución , Alimentación Animal/análisis , Animales , Bovinos , Femenino , Masculino , Estiércol , Modelos Biológicos , Modelos Estadísticos , Países Bajos , Nitrógeno/administración & dosificación , Nitrógeno/análisis , Nitrógeno/provisión & distribución , Fósforo/administración & dosificación , Fósforo/análisis , Fósforo/provisión & distribución , Potasio/administración & dosificación , Potasio/análisis , Potasio/provisión & distribución , Porcinos/metabolismo , Volatilización
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA