The environmental halo over the politically angelic head of biofuels is growing a new layer of rust.
Biofuels, according to early marketing, are environmentally benign because affiliated plant growth absorbs carbon dioxide enough to offset emissions from fuel combustion.
But that neat cycle isn’t the whole story. Meaningful production of biofuels requires expansion of agriculture, with all the land-use changes, fertilization, and irrigation that come with it.
Viewed systemically, biofuels have proven not to be the environmental balms their supporters make them out to be.
Now comes another environmental demerit: Crops grown as feedstocks for biofuel production can become “invasive species” threatening local ecosystems.
A new study for the Council of Europe, a group of 47 countries promoting democracy, human rights, and the rule of law, warns of disruption to “agroecosystems” resulting from European subsidies and mandates for biofuels.
“The characteristics of energy crop species, of their habitats, of cropping systems, and of farm subsidies are a ‘weedy merging
combination’ that could transform farmland into a source of new invasive species that may spread into vegetation remnant, ultimately harming the functionality and biodiversity within agroecosystems,” says one of the report’s more penetrable sentences.
The concern is that crops grown as raw materials for biofuels have characteristics enabling them successfully to compete for resources with native plants nearby. They grow and reproduce rapidly and use water efficiently. If not grown carefully, they spread beyond fields in which they’re planted.
Jatropha, a plant commonly grown as a biofuels crop, already has escaped and invaded native ecosystems, the study says.
Another plant cultivated for biofuel around the Mediterranean Sea, cardoon, a derivative of wild artichokes, is considered a pest in places like California, Western Australia, and South Africa. Sure enough, it’s spreading beyond plantation areas.
The European Union probably didn’t consider these effects when, in 2009, it set a 10% target for biofuels in transportation markets.
But environmentalists, who don’t like disruption to ecosystems, can be expected to force the issue.
(Online Dec. 24, 2010; author’s e-mail: email@example.com)