Despite the general eagerness to create alternatives to fossil fuels, some obstacles have arisen. Ethanol production has shown unexpected ramifications – from monoculture of crops like corn to increasing food prices. And now other biofuel side effects are under scrutiny.
The Global Invasive Species Programme (GISP) warns that hasty development of biofuel crops could result in the spread of invasive plant species. Further recommendations include careful selection of low-risk crops as well as management plans for introduced species.
Biofuel production is based on crop plants with rapid growth and high yields, as these will provide the maximum amount of plant material. So what exactly is the problem? Well, some introduced species become surprisingly efficient in new habitats, outcompeting local plants. After all, fast-growing and highly productive species have exactly the right characteristics to compete. Without native plants, other species also suffer and may not survive. In a ripple effect, invasive species can become so widespread that domestic agriculture is affected, and sometimes there are even health effects. The economic costs are enormous – about 1.4 trillion dollars are lost annually. In the US alone, combatting invasive species – plants and animals – consumes 120 billion dollars each year.
Controlling invasive species is notoriously difficult. Not only are the plant’s biological characteristics fine-tuned to rapid perpetuation, but animals may spread seeds and further assist the process. Sometimes labour-intensive mechanical control methods can work, often toxic chemical agents are the most effective. Even the control methods fuel debate.
A recent report examines specific plants that have caused problems. For example, the giant reed (Arundo donax) is originally native to wetlands in Eurasia. However, it has become successful in parts of North America, Australia, South Africa, and other regions. It has tremendously high water needs. As a result, the plants are often dry and easily ignite to spread wildfires. It is also proposed as a biofuel crop.
The African oil palm (Elaeis guineensis) is a second species of concern. Native to tropical forests in West Africa, it is grown as a biodiesel crop and has turned once diverse forest into unintended monoculture in Brazil. Like the oil palm, many invasive species are useful in their original habitats but pose problems elsewhere. The list includes grasses, trees, and even fruit-bearing plants like blackberry (a major weed in Australia and elsewhere) and osage orange.
The proposal is to inform countries that are about to promote biofuel crop production. The hope is that invasive species will be avoided, as the detrimental effects become known. Of course, there remains the potential for other species to prove invasive once they are brought into new environments, and this will be monitored. GISP is a collaboration including the International Union for Conservation of Nature (IUCN), the Commonwealth Agricultural Bureaux (CABI), the South African National Biodiversity Institute (SANBI), and the Nature Conservancy.