[COLOMBO] Global warming could adversely affect the production of coconuts — a staple fruit on which millions of tropical country inhabitants depend — scientists report.
Sri Lankan and US scientists analysed data on monthly rainfall from 1932 to 2003 in seven coconut-growing regions in Sri Lanka, and annual coconut production from 1971 to 2004. They found that coconut production was inhibited during drought years.
Using this data they developed a model to predict annual coconut production, based on temperature and rainfall patterns in its coconut-growing regions as well as greenhouse gas emission data.
Their analysis shows rising temperatures and rainfall changes could reduce coconut production through changes in fruit formation and nut development.
Sanathanie Ranasinghe, head of the plant physiology division at Sri Lanka's Coconut Research Institute (CRI) — one of the project partners — explains, "[Fruit formation] can be adversely affected, mainly due to a reduction in pollen quality and/or germination. The nut development can be affected, resulting in small number of nuts or empty nuts."
CRI scientists say the tree takes 18 months to mature, making it vulnerable to weather changes, particularly during the two dry seasons from January to March and July to August.
Millions of people in tropical countries depend on coconuts for food and cooking oil and use its fibres to make mats, mattresses, ropes, brooms and baskets. Sri Lanka alone produces 2.4 billion nuts every year, with 400,000 hectares, more than a fifth of its agricultural land, under coconut cultivation.
Studies are underway at CRI to determine the most sensitive stages of the coconut reproductive phase to high temperature and water stress and to assess the impact on coconut yield in different areas, land suitability classes and varieties.
A report published last month (30 March) by the US-based International Research Institute for Climate and Society (IRI) at the Columbia Climate Centre says the predictive model, which can yield a forecast 15 months in advance, have worked well since 2005 when they first started testing the model. CRI and the Foundation for Environment, Climate and Technology are now refining the model for regional and bimonthly forecasts, Lareef Zubair from IRI, told SciDev.Net.