Lungs of the earth
A senior botanist shares his thoughts on sustainable use of rainforests with HILARY CHIEW.
HAVING spent a good part of his research career in the Amazon jungles, Prof Sir Ghillean Prance does not want to see the world’s largest tropical rainforest disappear.
After the great destruction of the rainforest at a reported rate of 32,500ha a day or about eight football fields a minute in the 1980s and 1990s due to cattle ranching, the onslaught has not subsided.
Like many conservationists, Prance, who was director of the Royal Botanic Gardens Kew between 1988 and 1999, is perturbed by expanding soy plantations in Brazil.
“I’ll be meeting the Brazilian environment minister soon to discuss the impact of soy plantations. I think it’s my responsibility as a scientist to make use of the opportunity to talk to decision-makers and make meaningful intervention,” revealed the botanist during a recent visit to Kuala Lumpur.
Soybean, which originated from China, has taken root in cleared Brazilian forests as farmers have bred appropriate strains. Prance said soy plantation depletes soil fertility after some years, hence more forests need to be cleared for farmers to gain access to fertile land.
He advocates ethno-botany, a branch of botanical studies which acknowledges rainforest dwellers’ knowledge and sustainable extraction of plants.
Instead of cash crop production, he promotes sustainable harvesting of high value, non-timber forest products, such as the Brazil nut (Bertholletia excelsa), an important plant that has brought much-needed socio-economic progress to the interiors of Brazil.
An authority on tropical botany, Prance has led 16 scientific expeditions into various parts of the Brazilian Amazon and is known for his work on the Brazil nut.
His research on the coconut-sized nut uncovered a delicate web of ecological interdependencies. Female Euglossine bees (or Orchid bees), which pollinate the Brazil nut plant, hold one of the keys to the riddle of the species. They mate only with males which have successfully gathered a complete cocktail of scents from several orchid species – all of which grow only in undisturbed forest.
Understanding such interdependencies is vital for the survival of less economically significant species, and in turn conserves the biological diversity of the Amazon.
Brazil nuts come entirely from wild collection and have been touted as a viable species for generating income from a tropical forest without destroying it, if managed properly.
As the scientific director of the Eden Project in Cornwall, England, Prance continues with his campaign to integrate ethno-botany into the bigger conservation scheme to save the Amazon.
“Eden Project works through educating the public on the importance of plants to the world. We have an extension project in the field to stimulate change on the ground and these experiences are shared with visitors. For instance, we promote free trade products which reward the farmers for producing their crops in a sustainable manner that ultimately benefits them economically and ecologically,” he said.
It is not just for sentimental reasons that Prance is disturbed by the current land use pattern in Brazil. It is the role of the Amazonian rainforest in regulating global climate that is of great concern to the botanist who is also looking into the impact of a warmer earth from a botanical perspective.
Scientists have warned that carbon emissions reduce the amount of water vapour, released through evaporation, that feeds the region’s rain clouds.
The destruction of the Amazon might be large enough to change the climate of the rainforest and of the world. Last year, the Amazon experienced its driest year since 1926. Shallow rivers cut off river transportation and emergencies were declared for many interior towns.
Prance noted that the average first flowering date of 385 British plant species has advanced by 4.5 days during the past decade.
“Sixteen per cent of species flowered significantly earlier in the 1990s than previously. These data reveal the strongest biological signal yet of climate change. Flowering is especially sensitive to the temperature in the previous month, and spring-flowering species are most responsive. This will affect both the structure of plant communities and gene-flow between species as climate warms,” he added.
Under Prance, Kew Garden set up the Millennium Seed Bank to collect seeds from species that are threatened with extinction. The vaults now hold 700 million seeds representing 14,000 species from 126 countries. Stored at -20°C, most will last for more than 200 years. Faced with climate change, scientists are beginning to work on adaptation strategies, studying how seed quality varies with changes in climate.
Despite the grim outlook of the state of the earth, Prance is hopeful. He was particularly encouraged by the sight of participants in a cultural parade 2,400km up the Amazon River carrying placards with a green message.
He said environmental consciousness has grown over the years and people understand the significance of protecting the environment. “When more and more people learn about the environment, they can influence policies,” he added.
