South China Degraded Land Issues

Walter Parham, Ph.D.

November, 2014

China, the world’s largest automobile market, consumes one-third of the world’s natural-rubber,^1,2  and seventy percent of its own rubber resource to help meet the demand for automobile tires.²  India, the world’s 5^th largest rubber producer, also is increasing its rubber imports to meet the demand for auto tires.  India is forecast to be the world’s 3^rd largest car market in 2018.³

Asia produces about 97 percent of the world’s natural-rubber;⁴ Thailand, Indonesia, and Malaysia account for 70 percent with China at six percent.²   Large, monoculture rubber-plantations are a rapidly growing land-use today in the low lands of the China/Laos-Myanmar border region.  The plantation area grew almost nine times from 705 km² in 1980 to 6,014 km² in 2010.⁵ Now, large rubber plantations are pushing into the surrounding, higher elevations (300+ meter above sea level) of Cambodia, Laos, Myanmar, Thailand, Vietnam, and China’s Yunnan Province.  These higher-elevation, monoculture, rubber plantations are forecast to increase fourfold by 2050.⁴   In this border region, about 80 percent of the rubber plantations are situated at elevations between 600 and 1000 m, and about two-thirds of the rubber trees are grown on slopes of 8 to 25 degrees;

Rubber plantations cover hills of south Yunnan (photo by W. Parham, 1990)

China grows rubber on the steepest slopes and highest elevations⁵.  Higher-elevation, monoculture rubber-plantations increase soil erosion and risk damage to trees from cold temperatures.  Both negatively affect the long-term productivity of the sites and adversely affect the rubber trees and their latex production.

Latex tapping from rubber tree, Guangdong, PRC, photo by W. Parham

In 2000, I reviewed Chinese research on the rubber/tea agroforestry system, work that began in the early 1960s.  In light of the expansion of rubber-plantations, the Chinese rubber/tea agroforestry system seems worthy of reconsideration because of the system’s many environmental and economic benefits.  These include: reduced soil erosion; reduced runoff and fertilizer loss; rubber tapping one year earlier than normal; reduced tree damage from cold temperatures; extension of latex production; an assured, valuable second crop in case rubber trees receive severe wind damage.  Opportunities exist as well to incorporate high-value tea varieties not previously grown in this intercrop.  These advantages and others can help to extend the life of the rubber-plantations’ productivity.

(See  Related Publications above: The rubber/tea agroforestry system of South China: a short review.)

 Reference cited

1. China extends lead as world’s largest car market by sales, 2014; Young, A., http://www.ibtimes.com/china-extends-lead-worlds-largest-car-market-sales-gm-ford-china-deliveries-double-digits-1621254
2. Glut in natural rubber seen shrinking as prices drop and China car sales rise, 2014, Gallucci, M., http://www.ibtimes.com/glut-natural-rubber-seen-shrinking-prices-drop-china-car-sales-rise-1661682
3. Tyre demand boosts Indian rubber imports, may help revive global prices, 2014, Jadhav, , http://www.reuters.com/article/2014/08/13/india-rubber-imports-idUSL4N0QJ27620140813
4. Rubber plantations expand in mountainous southeast Asia: what are the consequences for the environment?, 2014, Fox, J.M., et al. http://www.eastwestcenter.org/sites/default/files/private/api114.pdf
5. Rubber plantations and its relationship with topographical factors in the border region of China, Laos and Myanmar, 2013, Xiaona Liu et al.; http://link.springer.com/article/10.1007%2Fs11442-013-1060-4

 https://walterparham.files.wordpress.com/2009/08/the-rubber-tea-agroforestry-system3.pdf