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Proposição de nova abordagem metodológica para o zoneamento agrícola de risco climático da cultura da soja no bioma cerrado
| Content Provider | Semantic Scholar |
|---|---|
| Author | Melo, Ana Clara Alves De |
| Copyright Year | 2015 |
| Abstract | The objective of this study was to compare two methodological approaches to climate risk zoning order to guide the soybean seeding (Glycine max (L) Merrill) in the Brazilian Cerrado. For this, we used a Water Requirement Satisfaction Index (ISNA), defined as the ratio of the actual evapotranspiration (ETr) and maximum crop evapotranspiration (ETm) to the frequency of occurrence of 80%, calculated in from the water balance of the culture, to the phenological stages considered most sensitive to water deficit: early development, flowering, and grain filling. The following information was used: precipitation; potential evapotranspiration; cycle time; cultural factors and useful reserves of soil water. Considered the municipality as low climate risk for sowing, when at least 20% of its area gave values of ISNA's higher than 0.40 in the early stage of development and greater than or equal to 0.65 at flowering stage and grain filling. There was the use of Regional Analysis System model of agro-climatic risk, then the data were georeferenced and spatially in a geographic information system (SPRING) which were made 72 maps for each approach. For the preparation of thematic maps, we used the computer program ArcGIS. It is important to point out that this study was based on simulated data in the Environmental Biophysics Laboratory in the period 2014-2015 and that there is no relation with other zoning of work already done at other times or with other authors. The comparison took place in three areas: (i) percentage of risk area class; (ii) number of municipalities recommended for soybean cultivation and (iii) of soybean sowing time. These three factors were analyzed to the traditional approach, which it considers critical stage only phase III, grain-filling flowering. Then, it was examined whether the new approach, which estimates the phase I + III, ie germination-emergence stage (IF), and flowering filler (FIII) as critical to the development of the plant. The comparison between the two approaches took into account the approach that possessed larger (or smaller) low-risk area percentage, which recommended larger (or smaller) number of municipalities, and which won (or lost) sowing seasons. It was found that the new approach presents a higher percentage of high-risk areas compared to the traditional approach; therefore more rigorous and restrictive. The biggest difference between zones of high risk of both approaches occur mainly at the beginning of the rainy season, October. The new approach offers greater number of municipalities not recommended for soybean seeding and fewer sowing dates favorable to soybean. In general, soils with less available water capacity are more restrictive to soybean sowing. The new approach has potential to offer lower risk investments in this current scenario of climate change, through recommendations that minimize possible damage due to recurring drought stress in two critical stages of soybean. Finally, the information generated in agro-climatic risk zoning study guide planners agencies, financiers and producers in decisionmaking and the shaping of public policies aimed at increasing the sustainability of soybean sowing in the Cerrado. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://bdm.unb.br/bitstream/10483/13788/1/2015_AnaClaraAlvesMelo.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
