Nearness to roads and palm oil mills a key factor in peatland clearing by smallholders

JAKARTA — Smallholder farmers in Sumatra who cultivate oil palms are more likely to expand their farms into carbon-rich peat forests the closer they are to roads and palm oil mills, a new study finds.

The study by researchers from the University of Maryland in the U.S. and Nanyang Technological University in Singapore looked at the spatial distribution and drivers of smallholder oil palm expansion into peat forests in the Indonesian province of Riau.

Riau has both the second-largest area of peatland in Indonesia and the highest palm oil production of any province in the country, with a rapid rate of expansion of smallholder farms.

This expansion has come at the expense of natural ecosystems, as farmers drain and clear peat swamp forests, a practice that releases large amounts of carbon into the atmosphere and contributes to climate change.

The researchers wanted to know what factors drive small farmers to clear peat swamp forests, given the dearth of research on the issue, especially for independent farmers cultivating plots smaller than 25 hectares (62 acres). The lack of data is also jarring given that smallholders manage nearly half of the total oil palm plantation area in Indonesia.

Jing Zhao, the study’s lead author and an agricultural economist at the University of Maryland’s Center for Environmental Science, said this gap might be due to the fact that smallholders’ expansion came later than the initial spurt of growth of industrial oil palm estates.

“[A]lso, ‘smallholders’ are by definition small individually and often widely scattered,” Zhao told Mongabay. “People may not realize that there is such a large amount of smallholder oil palm on peatland now and it is difficult to get data about smallholder oil palm.”

The researchers say the study is the first of its kind to use remote sensing and spatial data to identify drivers of smallholder expansion into peatland. It focused on oil palm smallholders operating on land that used to be peat swamp forest in 1990.

The researchers found that distance to roads and mills plays a critical role in driving this expansion. The odds of a given area of peat swamp forest being cleared for smallholder oil palm declined rapidly with increasing distance from roads and mills, according to the study.

For every kilometer increase in distance to the nearest road, the odds of peat forest conversion fell by 59%, and by 7% for every kilometer increase from the nearest mill, the study’s findings show.

It also found the spatial patterns of smallholder oil palm cultivation to be distinct from those of industrial oil palm plantations.

Since 1990 in Riau, 75% of smallholder oil palm farms that expanded into peat swamp forest were located within 1 kilometer (0.6 mi) of a roads; 90% were located within 2 km (1.2) of a road and 25 km (15 mi) of a mill, according to the study.

And for all land within 0.5 km (0.3 mi) of a road, smallholder oil palm accounted for the majority of land cover, the study shows.

It also found the mean distance from smallholder oil palms to the nearest road (722 ± 806 meters) is much shorter than for industrial oil palm estates (1,292 ± 1,330 m).

All these show “how dependent palm oil-producing smallholders are on road access,” Zhao said.

The crucial role that road access plays in smallholder expansion boils down to the nature of oil palm production, where timing is everything. When farmers harvest the palm fruit from the trees, they have to get it processed within 48 hours, otherwise the quality of the oil breaks down due to the effects of enzymes and oxidation.

“[B]ut smallholders generally do not have the means to transport their own goods to processing mills,” Zhao said. “Better access to roads benefits smallholders by reducing marketing and transportation costs thereby facilitating production and consequently improving socioeconomic conditions for smallholders.”

In addition to roads and mills, zoning factors such as the location of concessions and migrant settlements, and environmental factors such as precipitation and elevation, are important drivers of smallholder oil palm expansion into peatland, the study found.

It showed that smallholder oil palm farms are more likely to be located in regions with higher precipitation, higher slopes and lower elevation compared to other land cover types. It also found that the presence of concessions, typically held by industrial plantation companies, significantly restrict smallholder oil palm expansion.

According to the study, only around 50,000 hectares (123,600 acres) of smallholder oil palms, or 30% of smallholdings in Riau, were located inside oil palm concessions, while about 21,700 hectares (53,600 acres), or 14%, were inside pulpwood concessions.

When oil palm concessions are established, the odds of the peat areas inside them being converted into smallholder oil palm are about 77% lower than the odds outside concessions, the study found. Inside pulpwood concessions, the odds are 52% lower than outside them.

The researchers said smallholder oil palms usually don’t exist inside concessions because “the company would maximize the concession area for their own industrial plantations.”

Conservation opportunities

By understanding the drivers of smallholder expansion, the researchers said, stakeholders can identify strategies for slowing the deforestation of the remaining peat swamp forests in Riau and across Sumatra.

“Such knowledge is important in guiding future decisions for road infrastructure planning and forest conservation,” Zhao said.

This is especially important because even though Riau has lost much of its peat swamp forests, up to 70% since 1990,  nearly a third of peat swamp forests areas remain, spanning some 940,000 hectares (2.3 million acres).

“By accounting for the settlement patterns of smallholder farmers, both inside and outside concessions, unintended negative consequences for the conservation of the remaining peat swamp forests can be avoided,” the researchers said.

To make conservation efforts more focused and effective, the researchers identified regions that are at high risk of further conversion to smallholder oil palm plantations, determined from their distance to roads and mills. The researchers found 291,755 hectares (720,942 acres) of remaining peat swamp forest to be at high risk. Of these, 29,470 hectares (72,822 acres) are located within 2 km of roads and 25 km of mills, while 66,598 hectares (164,567 acres) are located within 2 km of a road, and 195,687 hectares (483,553 acres) are located within 25 km of a mill.

“Government should give more priorities in protecting these high risk areas,” Zhao said. “In addition, future roads and mills should be kept at a certain distance away from the remaining peatlands in order to limit oil palm expansion.”

To protect these high-risk areas, the government could designate them as protected areas, or place them under an existing moratorium on clearing peatland, the researchers said. The government could also expand its services in these high-risk areas to help smallholders identify effective ways to increase their income other than by clearing peat forests for oil palms. This could include efforts to improve yields and production from existing farmland, the researchers added.

There’s also a need for clear and updated concession boundaries, given that more than 30% of the remaining peat swamp forests lie within concessions, according to the researchers.

“Moreover, remaining peat swamp forests inside concessions could be used to generate carbon credits, if international carbon markets become well enough developed,” the researchers said.

Citation:

Zhao, J., Lee, J. S., Elmore, A. J., Fatimah, Y. A., Numata, I., Zhang, X., & Cochrane, M. A. (2022). Spatial patterns and drivers of smallholder oil palm expansion within peat swamp forests of Riau, Indonesia. Environmental Research Letters, 17(4), 044015. doi:10.1088/1748-9326/ac4dc6

 

Banner image: Roads divide a natural forest (left), oil palm plantation (bottom right) and timber plantation (top right) in Malaysian Borneo. Image by Rhett A. Butler/Mongabay.

 

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