The new land-use tsunami imperiling the tropics

Oil palm, oil palm, oil palm.  For years we've heard that a tidal wave of oil palm expansion is one of the biggest and fastest-growing threats to the world's rainforests.

But there's a new peril in town: rubber.  And it's also spreading like a destructive tsunami.

Spreading like wildfire

Spreading like wildfire

Two recent papers -- by Eleanor Warren-Thomas and colleagues and by Antje Ahrends and colleagues -- have underscored just how desperate the situation is becoming, especially in Southeast Asia.

As a result of escalating demand for natural rubber, plantations are increasingly gobbling up large expanses of land in Southeast Asia and the Asian mainland, as well as tropical Africa and Latin America. 

For instance, vast expanses of native forests have been cleared for rubber plantations in southern China,  which sustains many of that nation's biologically richest ecosystems

The current global production of rubber  (from Warren-Thomas  et al.  2015)

The current global production of rubber (from Warren-Thomas et al. 2015)

Warren-Thomas et al. see a rapidly worsening situation.  To meet expected demand, they estimate that from 4.3 to 8.5 million hectares of new rubber plantations -- an area up to three times the size of Belgium -- will be needed by 2024, threatening in particular significant areas of Asian forest, including many protected areas.

Expect especially rapid increases in rubber plantations in Laos, Cambodia, Vietnam, Thailand, Myanmar, Malaysia, and Indonesia, say the authors.

Ahrends and colleagues emphasize that rubber is now expanding into many areas that are ecologically marginal for rubber production.  In Southeast Asia, they estimate that 57% of the rubber plantations are currently vulnerable to droughts, erosion, frost, or wind damage.

Rubber is now spreading into marginal areas beset by high risks  (from Ahrends et al. 2015)

Rubber is now spreading into marginal areas beset by high risks (from Ahrends et al. 2015)

In 2013, for instance, typhoons in Vietnam alone destroyed over $US250 million in rubber plantations.  And future climate change could make conditions across Southeast Asia even worse for rubber, they contend.

The worst news of all is that native forests and other habitats are often being cleared for rubber production.  For example, say Ahrends et al., between 2005 and 2010, over 250,000 hectares of natural tree cover and 61,000 square kilometers of protected areas were converted to plantations in tropical and subtropical Asia.

This is scary news for the environment, for it suggests that a 'second tsunami' of forest-destroying plantations for rubber could soon follow just on the heels of the explosive expansion of oil palm.

 

Nature worth "$145 trillion per year" to humanity

Nature isn't priceless.  In fact, economists can give it quite a specific price: about $145 trillion per year, if the net value of all ecosystem services is tallied up.

What's a nice sunset worth?   (photo by William Laurance)

What's a nice sunset worth?  (photo by William Laurance)

Yes, that's 145 trillion dollars -- as in 145 with 12 zeros behind it. 

This new finding--which you can download free here--comes from a major analysis of global ecosystem services led by economist Robert Costanza of Australian National University.

Ecosystem services include a wide array of things such as carbon storage, crop pollination, fisheries, recreational opportunities, flood mitigation, and the provisioning of clean water.

While the new result underscores the astonishingly important role that nature plays in human welfare, there's also a kicker: the annual value of ecosystem services has declined by up to $20 trillion between 2007 and 2011, according to Costanza and colleagues, principally because of habitat destruction and other land-use changes.  And that erosion in value is ongoing.

Putting a price on nature is tricky and inevitably some people will object to the idea.  For instance, how can you place a dollar value on having clean air to breathe, or a wilderness to hike in, or hearing a rare bird sing?

But doing so underscores an important point: Even in the most utilitarian sense, nature has incredible value to humanity, and that value is being eroded.  Like any valuable resource, we're nothing short of foolish if we merely squander it.