Climate changes and technological advances: impacts on sugarcane productivity in tropical southern Brazil

Abstract

The climatic projections for this century indicate the possibility of severe consequences for human beings, especially for agriculture where adverse effects to productivity of crops and to agribusiness as a whole may occur. An agrometeorological model was used to estimate sugarcane yield in tropical southern Brazil, based on future A1B climatic scenarios presented in the fourth Intergovernmental Panel on Climate Change report, in 2007. Sugarcane yield was evaluated for 2020, 2050, and 2080 considering the possible impacts caused by changes in temperature, precipitation, sunshine hours and CO 2 concentration in the atmosphere, as well as technological advances. Increasingly higher temperatures will cause an increase of the potential productivity (PP), since this variable positively affects the efficiency of the photosynthetic processes of C4 plants. Changes in solar radiation and rainfall, however, will have less impact. PP will increase by 15% in relation to the present condition in 2020, by 33% in 2050 and by 47% in 2080. Regarding the actual productivities (AP), the increase observed in PP will compensate for the negative effect of the projected increase in water deficit. AP will increase by 12% in relation to the present condition in 2020, by 32% in 2050 and by 47% in 2080. The increase in sugarcane productivity resulting from the projected scenarios will have important impacts on the sugarcane sector. Key words: global warming, water balance, agrometeorological model, sugarcane yield MUDANÇAS CLIMÁTICAS E AVANÇO TECNOLÓGICO: IMPACTOSNA PRODUTIVIDADE DA CANA-DE-AÇÚCAR NA REGIÃO CENTRO-SUL DO BRASIL RESUMO: As projeções climáticas para este século indicam a possibilidade de graves conseqüências para a humanidade, especialmente para a agricultura, com efeitos adversos nas produtividades das culturas e no agronegócio como um todo. Neste estudo, foi utilizado um modelo agrometeorológico para estimar a produtividade da cana-de-açúcar na região de Piracicaba, SP, Brasil, baseado nos cenários futuros do clima A1B, apresentados no quarto relatório do Painel Intergovernamental sobre Mudanças Climáticas, de 2007. A produtividade da cana-de-açúcar foi avaliada nos anos de 2020, 2050 e 2080, levando-se em consideração as possíveis alterações de temperatura, precipitação, insolação e concentração de CO 2 na atmosfera, assim como os avanços tecnológicos. O aumento da temperatura acarretará no aumento da produtividade potencial (PP), já que essa variável afeta positivamente a eficiência do processo fotossintético das plantas C4; entretanto, as alterações na radiação solar e na chuva terão menores impactos na produtividade.

Climate trends in a non-traditional high quality wine producing region

“…In this sense, the agrometeorological researches need to evaluate the possible impacts of the current climate change on agriculture (Zullo Junior et al, 2006) because any change in the climate pattern of a given region may impact the crop development (Gouvêa et al, 2009). Regarding the influence of the climate on grape wine production, it is well known that the regional atmospheric conditions strongly influence the regional wine style (Jones et al, 2005;Orlandini et al, 2009).…”

Unfavourable thermal conditions of air at the turn of the 20th and 21st centuries reducing crop productivity of pickling cucumber (Cucumis sativus L.) in Poland

“…It is difficult to explicitly determine when thermal conditions are a stressor because reaction to different levels of air temperature (T a ) depends on several factors. These factors are: plant adaptation to different climatic zones, duration of stressor impact and its intensity, development stage and physiological activity of a plant (Blum, 1996;Gouvêa et al, 2009). Disturbance in the growth and development of vegetables and, as a consequence, reduction in its cropping, is a negative effect of stressors.…”

Offsetting high water demands with high productivity: Sorghum as a biofuel crop in a high irradiance arid ecosystem

“…Seasonal water evaporation for sorghum was 1094 mm H 2 O (Table 1), similar to alfalfa in the Imperial Valley (1270 mm season À1 ) (Sanden et al, 2011). However, the productivity of sorghum was almost twice that of alfalfa (Sanden et al, 2011), therefore the growing season BWR of sorghum was relatively high (4.0 and 1.9 g kg À1 for sorghum and alfalfa, respectively; (Gouvêa et al, 2009;I.B.G.E., 2013). Overall, sorghum's seasonal water use was high compared to biofuels in the Midwest, but similar to those of other crops grown in the Imperial Valley and sugarcane in Brazil.…”