Abstracts
Nº 21
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Abstracts |
Nº 21
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Technical and Natural Sciencies
The (Interactive) Science Museums. An emergent social event |
Agustín Carpio, Jacinto Corujo, Roberto Ronchi |
| Key Words: Interactive Science Museums - Itinerant Museums - Science Teaching - Science popularizing - Interactivity |
| In this article a review of the current state of Science Museums, with special reference to the so characterized as interactive ones is presented. Comments are made upon the criteria being held to create and organize such institutions, and their cultural and educative supporting principles, aiming to point out that they also are political expressions. We gathered the opinions from qualified people working on the development of this type of museums in several countries, in special in our Continent. Through them it is possible to view much of the common basis being shared by these museums, in spite of differencies such as size or complexity. |
Evaluation
of Soil Phosphorus Fertility for the Main
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René Benavídez et al. |
| Key Words: Phosphorus- Plants nutrition - Adsorption - Crops - Soils |
| Due to phosphorus
strongly interaction with soil solid phase, we outlined the hypothesis that
soil characteristics affect the interpretation of chemical analyses of P
availability for plants and fertilization recommendations. Greenhouse essays
were carried out using many varied soils with wheat, soybean, corn, flax,
sunflower, sorghum, alfalfa and bridsfood cultures. It was observed that
Entre Ríos soils show a medium to very low P buffer capacity and
that this capacity is related to the clay and Fe and Al amorphus materials
content. We could prove that chemical indexes such as Bray's constitute
to a great extent the soil factors that make P availability for plants,
not requiring any additional information for their interpretation. However,
in order to make appropriate fertilization recommendations, it is necessary
to know the soil P buffer capacity. |