Fidelis E. Satriastanti
The Ministry of Forestry voiced concern on Friday about invasive plant species that are beginning to threaten native vegetation and wildlife.
“At Baluran National Park, the original ecosystem was savanna but now it is dominated by Acacia nilotica, which is native to India,” said Adi Susmianto, head of the ministry’s conservation and rehabilitation research center. “Nearly 50 percent of the park is covered with acacia, that’s around 7,000 hectares of land.”
Acacia was originally planted on the fringes of the national park, located in East Java, to prevent wildfires from spreading, but the plant was soon dominating the park, leaving the native bull without enough space to graze.
“There used to be 200 bulls and now there are 34,” Adi said.
Bukit Barisan Selatan National Park, located in three provinces in Sumatra, is under threat from the similarly invasive Merremia peltata, a type of morning glory known locally as mantangan, Adi said.
The plant is indigenous to the area but has spread over 10,000 hectares of land at the national park, threatening other types of plants.
Adi said both parks would host a pilot project aimed at controlling the spread of invasive plants.
Soekisman Tjitrosoedirjo, a plant physiology expert, said invasive plants could have an adverse effect on native trees and weeds, and ultimately force local wildlife to relocate or die of starvation.
“If you see Baluran National Park from above, it is no longer a savanna because it is now filled with Acacia nilotica. The more we try to destroy this acacia, the more other invasive plants will take its place,” he said.
Soekisman said the government introduced the plant to the area to prevent forest fires from spreading, but that the plant turned out to be too well-suited for the environment.
“The acacia replaced the savanna ecosystem because its ability to absorb nitrogen from the air has made the land more fertile,” he said.
“Plus, acacia seeds can easily spread so they grow close together, making it difficult for animals to find food.”
In Bukit Barisan, the mantangan is thriving due to the unchecked land clearance in the area.