Necesidades y perspectivas agronómicas de fertilizantes y enmiendas en Venezuela
Las limitaciones más importantes de los suelos en Venezuela son: aridez la cual representa el 4% del territorio, 18% del área total presenta problemas de drenaje, 32% tienen baja fertilidad y acidez, 44% esta limitada por pendientes donde la conservación de suelos es obligada y solo un 2% del área total no tiene limitaciones. Los productores venezolanos usan principalmente fertilizantes tradicionales: simples o granulados NPK. La demanda nacional de nitrógeno es producida en el país y las necesidades de fósforo y potasio son cubiertas por importaciones. Los planes contemplan el desarrollo de las fuentes locales de fosfatos de manera que se espera que en el año 2000 se cubra el 80% de la demanda del país. Venezuela continuará dependiendo del potasio importado. El subsidio a los fertilizantes fué eliminado totalmente en septiembre de 1993. Algunos fertilizantes no tradicionales son usados o tienen posibilidades en la agricultura venezolana. El amoníaco anhidro tiene un gran potencial para la caña de azúcar y el arroz, el tiosulfato de amonio en suelos neutros y alcalinos, las rocas fosfóricas micronizadas, parcialmente aciduladas compactadas o como fuente de fósforo de baja solubilidad en las mezclas NPK, son usadas en cultivos anuales y permanentes con éxito. También están bajo estudio la posibilidad de producción de potasio a partir de las fábricas de cemento y de las salmueras donde se produce el cloruro de sodioPor otro lado, el uso de cales agrícolas, fosfoyeso y estiércol favorece la eficiencia de los fertilizantes y el manejo de suelos marginales con limitaciones físicas y químicas. .Palabras claves: aridez, drenaje, pendiente, acidez, fertilizantes tradicionales y no tradicionales, subsidio.AbstractVenezuela needs to analyze the fertilizer requirements, modifying the tendency to consume annually high volumes of bagged complex NPK fertilizers to bulk blends.The gradual reduction of the fertilizer subsidies imposes international prices in the Venezuelan markets which in turns opens excellent opportunities for business and demands efficient fertilizer use. Fertilizers will have to be adapted to the soil-crop-climatic conditions of the country. In this paper it is presented an agronomic outlook of Venezuela and the estimated requirements of traditional and non traditional fertilizers.The most important soils limitations in Venezuela are: aridity which represents 4% of the territory, 18% of the total area presents drainage problems, 32% presents low fertility and acidity, 44% is limited by steep slopes where soil conservation is mandatory, and just 2% of the total area has no limitations. The Venezuelan farmers use mainly traditional fertilizers: simples or granulated NPK'S. The domestic demand of nitrogen is locally manufactured phosphates and potassium needs are covered by imports, the plan contemplates development of local phosphate sources so that by year 2000 it is expected to cover 80% of Venezuelan phosphate demands. Venezuela will continue dependence of imported potassium. Subsidy has been totally eliminated in september 1993. Several non traditional fertilizers are used or have possibilities in Venezuelan agriculture. Liquid Ammonia has a great potential for sugar cane and rice, ammonium tiosulphate in alkaline and neutral soils; phosphate rocks micronized, partially acidulated, compacted or as a low soluble P source in granulated N-P-K, are used in permanent and annual crops successfully. There is also a possibility, under study, of K production from cement factories and from the brines where sodium chloride is produced.On the other hand, the use of lime, phosphogypsum and manure favors fertilizers efficiency and management of marginal soils with chemical and physical limitations. The total surface to be planted and fertilized in Venezuela from 1992 to 2000 has been projected, based on several factors as crop yields, soils quality and crop N-P-K requirements. The average interannual growth rate for that period has been estimated in 3.46% and 3.07% for the surface to be planted and fertilized. It is projected an average formula for 1992 to 1995 of 18-13-11 of N - P2O5 - k2O and 19-12-12 for 1996-2000, with an average consumption of fertilizers of 535 and 511 kg/ha for both periods, for a total of 1.340.000 ton in 1992 and 1.700.000 ton for the year 2000.Index words:aridity, drainage, acidity, slopes, traditional and non traditional fertilizers, subsidy.
| Main Authors: | , , , , |
|---|---|
| Format: | Digital revista |
| Language: | spa |
| Published: |
Instituto de Edafología, Facultad de Agronomía, UCV
2011
|
| Online Access: | http://saber.ucv.ve/ojs/index.php/rev_venes/article/view/1007 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|