1. Risky economics of rubber
plantations
Ahrends, A., Hollingsworth, P. M., Ziegler, A., Fox, J., Chen, H., Su, Y., Xu, J.

2. Expanding rubber plantations
• Natural rubber (Hevea brasiliensis) major source of world’s rubber for
high pressure applications.
• Used in manufacture of >1 billion tyres per year.
• Rubber prices have tripled in the last decade (Chinese car industry).
 rubber production globally has increased by 50% since 2000
 rapid land use conversion to rubber in SE Asia (supplies 97%)
7
6
Natural rubber
price (US$/kg
RSS3 SG)
5
4
3
At 1 US$/kg
conversion
generally
lucrative
2
1
2012
1998
1984
0
Source: index mundi

3. credit: Science 2009 324:1024
credit:
Nature 2009 457:246
credit: Science 2009 324:1024
Rubber plantations Xishuangbanna, China, 2010
>20,000 km2 have been converted to mono-culture rubber in mainland SE
Asia (5,000 km2 forest)

4. Environmental/social implications
• Often planted by small-holders  brought wealth to impoverished areas.
• Dependence global markets of small-scale farmers. Less food security?
• Clearance of primary and secondary forest (biodiversity, carbon).
• Rubber pulls water from sub-soils in dry season  groundwater reserves.
• Heavy use of fertilisers and pesticides  water contamination.
Xishuangbanna, China 2013
Laos 2009 (Mongabay)

5. Rapid and large-scale land conversion to rubber all over mainland SE Asia in
areas previously regarded as unsuitable for rubber  consequences?
No systematically collated evidence whether rubber can tolerate marginal
environments (long-term) or whether there is a concern.
Study aims:
1. Quantify extent to which plantations have moved in marginal areas.
2. Tease out the different types of risks and establish whether there is
evidence for poor plantation performance in relation to these risks.
 Provide region-wide overview and much needed information to guide
management and policy.
Xishuangbanna, China (Google Earth Jan 2013)

6. Global bioclimatic model of suitability for rubber
(based on the natural distribution of H. brasiliensis)
High
Low

7. Spread into non-traditionally suitable habitats
0
250
500 km
Traditional rubber-growing
space is becoming scarce.
90% of plantations are now
located in non-traditional
habitat.
In many of these areas
rubber
seems
to
be
currently performing fine
but
this
does
not
Environmental suitability equate to longnecessarily
High
term sustainability.
Low

8. 63% of plantations now situated in risk zones
>3,800 km2 in
zones with
frequent extreme
events (e.g.
typhoons, frost)
typhoon zone
high-alt. zone
frost zone
dry zone

9. Recent examples of storm and frost damages
• Loss of plantations worth US$250 Mio in Vietnam due to typhoons Wutip
and Nari (Sep-Oct 2013); additional loss due to Haiyan (Nov 2013).
• Cold weather kills 95% plantations in 4 Provinces in Vietnam in 2010.
• Freezing hazard in China causes major damage to plantations in 2008.
• A typhoon causes devastating plantation loss in Hainan, China in 2005.
http://tuoitrenews.vn/society/13714/devastating-loss-of-rubber-forests-to-typhoon-wutip

10. 63% of plantations now situated in risk zones
>3,800 km2 in
zones with
frequent extreme
events (e.g.
typhoons, frost)
>6,300 km2 at
>900 m altitude or
on slopes >24⁰
typhoon zone
high-alt. zone
frost zone
dry zone

11. Risks at high altitudes and steep slopes
• Plantations >900 m and/or slopes >24⁰ not deemed economically viable1.
• Soil compaction, erosion, stream sedimentation, risk of landslides
(e.g. hazardous landslide southern Thailand 1988)2.
 small-scale farmers may be left with degraded land.
Rubber plantation on slope
Natural forest on slope
(1) Yi et al. 2014. Ecol. Indicators 36: 788-797
(2) Li et al. 2012Environmental Management 50: 837-848

12. 63% of plantations now situated in risk zones
>3,800 km2 in
zones with
frequent extreme
events (e.g.
typhoons, frost)
>6,300 km2 at
>900 m altitude or
on slopes >24⁰
>3,300 km2 in dry
zone
typhoon zone
high-alt. zone
frost zone
dry zone

13. Risks in dry zones
• Reduced yield, and no yield during the dry season (up to 5-6 months).
• Loss of US$26 Mio plantations in Xishuangbanna, China in drought 2010.
• Mortality of trees up to 50% in dry provinces in NE Thailand.
• 24% reduction in yield in Hainan, China during drought in 2005.
• Plantations may deplete ground water.
Rubber in dry season, Phitsanulok, Thailand
Yunnan, China 2010

14. Net exacerbation of marginality with future
climate change
39 models (CMIP Phase 5) across RCPs 2.6, 4.5, 6.0, 8.5 for 2050
• Temperature increase in 100% of rubber area (decreased frost risk).
But
• Generally seasonality will increase.
 Increased rainfall wet season in 96-100% of area  erosion/landslides
 Increased risk of drought for 43-77% plantations in dry zone
• The number and severity of typhoons may increase.
Landslide SW China (www.news.cn)
Yunnan, China 2010
Typhoon Haiyan (Karen Nyberg, ISS)

15. Global consumption expected to increase
Regional rubber consumption
• Consumption increase 2-3% yr-1.
• Available stocks likely to
decrease relative to demand.
 Rubber prices likely to remain
high/increase.
Natural vs. synthetic rubber
• Synthetic rubber does not
match performance.
• Production price high (coupled
with Crude Oil price).
 No immediate alternatives.
The Rubber Economist Ltd. Quarterly Report (2013)

16. Conclusions
1. Increasing demand for rubber will continue to lead to land conversion.
2. Conversion to cash-crops is the main driver of forest loss in SE Asia.
Plantations increasingly in areas with potential environmental risks.
3. Possibility for worst-case “loss-loss” scenarios: conversion of highbiodiversity value land to mono-culture plantations which yield shortterm returns before becoming degraded and abandoned.
4. Study highlights urgent need for systematic monitoring of plantation
losses. Policy interventions and agro-forestry practices (intercropping)
may be necessary to avoid loss-loss scenarios, and to reduce exposure
of small-holders to economic risks.