GM crops: Good or bad for nature?

One of the more heated controversies in conservation science concerns genetically modified crops.  Are GM crops a boon for conservation or a serious danger?

On the one hard are those who believe GM crops are vital to increase agricultural production (and in some cases to reduce pesticide use), thereby allowing us produce more food on less land and spare more land for nature conservation.  The followers of this view often see the anti-GM crowd as hopelessly misguided or naive.

On the other hand are those who see potential dangers in GM crops -- ones that might outweigh their benefits in some if not many cases.  The term "Frankenfoods" has sometimes been applied to GM crops, reflecting the fear that these genetically modified foods might have a darker side.

ALERT member Jean-Philippe Puyravaud from India counts himself among those who worry about GM crops.  Here he tells us about his fears about one crop in particular.

A genetically modified crop is produced by introducing genes from another species, and the Bt. brinjal (a type of modified eggplant) was developing by introducing genes from a bacterium (Bacillus thuringensis) that is resistant to borers and caterpillars. 

However, GM organisms pose potential risks such as creating more vigorous pests, and could harm non-target species and disrupt biotic communities.

A recent study concludes that hybridization is possible between wild and cultivated brinjal in southern India, and another study showed there is a clear potential for transgenes to spread to wild brinjal populations.

Hence, the risk of transgene escape to wild or domesticated plants cannot be ignored.  Before introducing a GM crop, it is vital to check whether its genes can be transferred to wild relatives via pollinators.

Yes, we need to feed a hungry world.  But GM crops are not a panacea.  We have to study each one, on a case-by-case basis, before deciding whether or not its benefits will outweigh its risks. 

 

Will new supercrops feed the world and help save nature?

We live in a hungry world -- and one that will soon grow much hungrier.  Global food demand is expected to double by mid-century because of rapid population growth and changing food habits.  Producing that much food could require a billion hectares of additional farmland -- an area the size of Canada.

But if we develop new high-yielding 'supercrops' and farm them intensively, could we feed the world with less land and thereby spare some land for nature?  Many have argued in favor of this idea.

A tsunami of oil palm  (photo by William Laurance)

A tsunami of oil palm (photo by William Laurance)

But a new study published in the leading journal Science suggests the opposite: supercrops will actually encourage more habitat destruction for agriculture, especially in the species-rich tropics.

The authors argue that new varieties of palm oil, which are highly productive and profitable but grow only in the tropics, are simply going to keep spreading apace.  That's because there's so many different uses for palm oil, including for many food items, cosmetics, and biofuels, that demand for it will remain high.  

And, as palm-oil production rises, its price will likely fall, meaning that it will increasingly out-compete other oil-producing crops, such as canola (rapeseed), sesame seeds, and peanuts.

This, the authors say, will simply shift the footprint of agriculture from areas such as North America and Europe to mega-diversity regions such as the tropical rainforests of Southeast Asia, Latin America, and Africa.

What's the answer to the tsunami of oil palm and other profitable tropical crops?  There really is only one alternative: we need proactive land-use zoning to determine where agriculture should and should not go -- to ensure it doesn't just overrun nature.  And we need better law enforcement to reduce illegal deforestation.

And we direly need to limit the explosive expansion of roads into wilderness and high-biodiversity areas.  By 2050, it's expected that we'll have an additional 25 million kilometers of new paved roads -- with nine-tenths of these in developing nations that sustain many of the world's biologically richest ecosystems.

There really is no other option.  Supercrops may help feed a hungry world, but if they're not constrained they will destroy much of nature in the process.

 

Where on Earth should roads go and not go?

"The best thing you could do for the Amazon is to blow up all the roads."

Road to ruin?  (photo by Rhett Butler)

Road to ruin? (photo by Rhett Butler)

Those might sound like the words of an eco-terrorist, but it's actually a direct quote from Eneas Salati, a forest climatologist and one of Brazil's most eminent scientists.

Salati was saying it straight: far too often, roads open up a Pandora's Box of environmental problems -- allowing illegal loggers, miners, hunters, or land speculators to invade forests and other native ecosystems.  The results are often disastrous for nature.

But societies need roads -- for economic growth, to access land and natural resources, and for scores of other reasons.  Where on Earth should roads go and not go?

Today, in the leading journal Nature, ALERT director Bill Laurance and a team of co-authors from Harvard, Cambridge, Melbourne, James Cook and other universities present a global strategy for road building. 

Their paper advances a strategy for zoning and optimizing road locations, by assessing the relative environmental costs and economic benefits of road construction for every square kilometer of land on Earth.

You can download the paper for free here

And here is an insightful News & Views piece that Nature published about the article. 

And here is a popular, easy-to-read article that hits all the key points.

This paper has striking implications.  It shows the most critical areas to keep road-free, the areas where roads can have the greatest benefits for improving human welfare and food production, and the places where environmental conflicts are most likely to arise in the future.

By 2050, it's expected that there will be 25 million kilometers of new roads -- enough to circle the Earth more than 600 times. 

Nine-tenths of these new roads will be built in developing nations that sustain the biologically richest and most environmentally important ecosystems on the planet.

Deciding where this avalanche of new roads will go -- and not go -- is among the most critical environmental challenges we have ever faced. 

Why are we so afraid to talk about human population?

When it comes to the environment, human population is the 900-pound gorilla in the corner.  I know this from first hand--I once got into hot water for a New Scientist piece that slammed conservatives in the U.S. for failing to support family planning.

People are great, but enough already... (photo by William Laurance)

People are great, but enough already... (photo by William Laurance)

Now, in a provocative essay, Jonathan Porritt asks why is nearly everyone--including most leading environmental groups--so reticent to talk about population?

It's a good question.  According to the U.N. Population Division, Earth's population is projected to peak at nearly 11 billion people this century. 

Africa will have 400% more mouths to feed, according to the U.N.  Nigeria--already teetering on the edge of social and economic chaos--will have five times its present population.

These are incredible figures, and they underscore momentous challenges ahead--for global food security, social welfare, immigration and national security issues, and of course the environment.

The challenge is growing.  According to a recent analysis by Leontine Alkema and colleagues, by 2015 nearly a billion women will need contraception or will have an unmet need for contraception.  This number is rapidly increasing, especially in developing nations.

Demographers like Alkema keep saying the same thing: One of the smartest long-term investments we can make today is in family-planning and contraception, especially where population growth is fastest and most likely to be destabilizing in the long term.  A good place to start is Africa.

We need a lot more talk--and action--on population.

-Bill Laurance

Agriculture will massively impact the tropics

In a review article that has just appeared in the leading journal Trends in Ecology & Evolution, I teamed up with Jeff Sayer and Ken Cassman to assess the impacts of agriculture this century on tropical ecosystems and biodiversity.  It's quite a sweeping review with many important conclusions.

Oil palm: highly profitable and often deadly for tropical forests (photo by Niels Anten).

Oil palm: highly profitable and often deadly for tropical forests (photo by Niels Anten).

Among the biggest concerns are:

- Prospects for dramatic expansion of agriculture in Sub-Saharan Africa and South America

- Great uncertainty in the amount of land that will be converted to agriculture, in order to meet growing global food demands

-The prospects that biofuel production could also impact greatly on native ecosystems and also compete with agriculture

- The likelihood of massive environmental impacts on freshwater ecosystems and water supplies

- Profound challenges ahead in producing enough food to feed the world

Those who wish to have a PDF of the paper can email me directly (bill.laurance@jcu.edu.au).

-Bill Laurance