Page 72 - Ecuador's Banana Sector under Climate Change

ecuador’s banana sector under climate change: an economic and biophysical assessment to promote a sustainable and climate-compatible strategy
America.23 Thus, the two major competitors to Ecuador in exporting bananas - Central America and the Philippines - are adversely affected by forecast climate change and proportionately more so than Ecuador.
Higher temperatures improve the suitability of banana production in the subtropics, defined approximately as between 20o and 30o North and South, respectively. In this zone, the current limiting factor to banana production is the high risk of damage at cool temperatures (minima below 10oC and averages below 16oC). Higher mean minimum temperatures reduce this risk and increase banana suitability. Van den Bergh et al. (2010) calculate that suitability improves greatly in southern Brazil (São Paulo to Pôrto Alegre) and in southern non-coastal China (interior Guangdong). Domestic demand is likely to absorb any increase in Chinese production, but Brazil may have an increased exportable surplus.
Higher temperatures will increase the maximum altitude at which bananas can be produced. As highland banana production is generally for local and household consumption rather than for export, this is unlikely to be an important direct influence on banana trade, but it could have a major impact on food security in areas where bananas and plantains play a major dietary role.
4.1.2 Disease
Global climate change will influence the incidence and severity of plant disease. The two major diseases of bananas are Black Sigatoka (Mycosphaerella fijiensis) (BS) and Panana disease (Fusarium oxysporum f. sp. cubense)
(Ploetz et al., 2003).24 Júnior et al. (2008) have analysed how climate change
is likely to favourably influence the development of BS. IPCC-based forecasts of temperature and precipitation by area and month are combined with BS- favourability levels (Table 8) to generate BS-favourability scores by area and by month. Because BS has adapted to the banana, it is hardly surprising that BS-
Table 8 Climate favourability for Black Sigatoka
Favourability for Black Sigatoka Highly favourable Favorable
Relatively favourable Little favourable Unfavourable
Temperature intervals
(oC)
25-28
25-28 20-25 or 28-35 20-35
< 20 or > 35
Relative Humidity Intervals
(%)
> 90
80-90
> 80
70-80 < 70
Source: Jesus Júnior et al., 2008, Table 1, pg. 42
23 IPCC (2007:778): “The monsoonal precipitation in Mexico and Central America is projected to decrease in association with increasing precipitation over the eastern equatorial Pacific that affects Walker Circulation and local Hadley Circulation changes.”
24 Ghini et al. (2011) review the emerging literature modeling the influence of climate change and the distribution of tropical and plant diseases on plantations
56