Almost every human ear on the planet has heard the phrase “global warming.” Most of us here in the U.S. know what global warming has been up to lately: hurricanes, etc. But today I want us to look at how this same phenomenon is impacting other parts of the globe. Let’s fly to (not literally) East Africa’s beautiful island of Zanzibar from where I wish to share excerpts of a recently published climate change report, which details the impact of rising ocean temperatures on the livelihood of seaweed farmers.
According to the report, until a few years ago, mariculture – the cultivation of marine organisms in open ocean waters – employed 15,000 to 20,000 ‘farmers’ in Zanzibar, most of them women, and seaweed was one of the island’s biggest exports, after spices and fine raffia. Seaweed was introduced to Zanzibar from the Philippines in the 1980s.
Sea weed has numerous usages and some varieties used in the food and pharmaceutical industries as a stabilizer or emulsifying agent, are in great demand abroad, and the Tanzanian government promoted it as an export crop acting both as a source of employment and revenue. For a long time since its introduction, demand has been strongest for high quality red seaweeds such as the Cottonii and Spinosum varieties, but seaweed farmers say those varieties are now proving very vulnerable to changes in growing conditions, which can make the weed lose its colour and, most importantly, its texture. As an apparent result of warming conditions and storms, Zanzibar’s seaweed production has fallen sharply in recent years, from 14,040 tonnes five years ago to just under 10,800 tonnes last year, according to the Department of Marine Resources of Zanzibar. The Zanzibar Exporters Association said its members collected and exported about 11,000 tonnes of dry seaweed in 2011, most of it going to the United States, France, Denmark, Spain, China and Chile.
Experts have linked the sharp fall to warmer water and turbulent conditions on the seabed because of more extreme weather. Farmers and researchers now hope to create new farms in deeper water, at the lower temperature the seaweed prefers.
According to the Institute of Marine Sciences at the University of Dar es Salaam, temperatures in the shallow seaweed farms have increased from below 30 degrees centigrade in the 1990s to about 38 degrees centigrade and slightly above recorded recently. The Western Indian Ocean Marine Science Association (WIOMSA), which promotes the conservation of resources and ecosystems on Indian Ocean islands, confirms that weather patterns around Zanzibar are undergoing great changes. As pointed out in the report, the 2011 rains that killed 20 people in Dar es Salaam – and which the Tanzanian Meteorological Agency described as the heaviest downpour there since independence in 1961 – also affected seaweed farms on the coast of Zanzibar. As a result of unstable ocean levels, seaweed farms are sometimes washed away by heavy ocean storms resulting in huge losses to farmers.
In a bid to find a lasting solution to the crisis, the University of Dar es Salaam has now initiated research on new techniques of seaweed farming that would be resilient enough to the changing coastal conditions. According to the report, such research is currently focused on the development of deep-water floating seaweed farms that would enable farmers to grow seaweed, particularly the favoured red varieties, at the low water temperature the plants prefer so that their livelihood is not compromised.
Read the original report here AlertNet