Last Friday, a team of researchers from the University of the Philippines Los Banos published an article. Working under the supervision of Prof. Edwino Fernando, they wrote about the world’s first study on the discovery of a new plant species with nickel hyper-accumulating capacities. The plant in question, discovered on Luzon Island, has received the name Rinorea niccolifera. The epithet niccolifera means just that: this is a plant in whose stem and leaf tissues can hyper-accumulate high amounts of nickel. The quantity of nickel it can hold without becoming poisoned is up to 18,000 ppm, says the professor. That’s about a thousand times more than other plants capacity to hold metal!
The plant is a shrub or small tree which can grow up to 1.5 (or 1.8) meters tall. It has a stem with a 3 to 13 cm diameter and its outer bark is generally smooth. The inner bark is a hue of white, while the leaves are simple, with a distichous shape. The lamina usually have an elliptic shape or narrow, ovoid shape. The plant grows in forests with ultramafic soils. They usually grow along gullies or slopes with large boulders. The plant thrives at an elevation level of 320 to 825 m.
How New Plant Species Can Clean Up our Industries
Nickel hyper-accumulation is an extremely rare phenomenon: only .5 to 1 percent of all the plants that are native to areas with soils rich in nickel are able to do it. Hyper-accumulation means the plant in question can process soils that have an overabundance of metal without becoming poisoned. This hyper-accumulation holds a lot of potential for cleaning up humanity’s tech act. According to science, there are some 450 known hyper-accumulator plant species at a global level. This number is next to nothing compared to the 300,000 known species of vascular plants in the world. It’s interesting to wonder why we have such plants in the first place: science speculates that they have emerged as a means to deter herbivores from eating them. Another alternative is that the plants’ own levels of toxicity also increases the toxic levels of anti-herbivory metabolites.
A paper published in the PhytoKeys journal by a team of researchers lead by Augustine Doronila, from the University of Melbourne, sheds light on what such plants can mean for the future of technology. Their benefits are two-fold: on the one hand, they’re capable of phytoremediation. On the other, they can aid with phytomining. Here’s a cursory rundown of these two concepts:
- Phytoremediation means that these plants could remove dangerous metals from the world’s water supplies as well as from the ground. In plain English, they could help decontaminate areas tainted by heavy metals.
- Phytomining refers to these plants’ usefulness in the harvesting of heavy metals and other metallic substances with commercial value. This process can be achieved by planting such species in metal-rich sites. People could then harvest the plants and turn them into metals.
Such plants have already been used for both of the purposes described above. One experiment funded by a SAPS Associates Award and based on a protocol written by Helen Bailey, used phytoremediation to decontaminate soils of copper. The soils had become infiltrated with copper as a result of mining and manufacturing activities. The phytoremediation was followed by phytomining, all with the aid of hydroponically grown Indian Mustard (Brassica Juncea). Robert R. Brooks also authored a study on plants that accumulate heavy metals and their use in various technological and scientific fields such as microbiology, archaeology, and mineral exploration. Brooks also touches on the role of hyperaccumulators in geobotany, biogeochemistry, and phytoarchaeology. He argues for the revegetation and stabilization of degraded terrains such as mine dumps with the aid of hyper-accumulating plant species. He also investigates the use of seaweeds and other prokaryotic microorganisms as hyperaccumulators.
A Cleaner Future Thanks to Plant Species?
Rinorea Niccolifera, like all hyperaccumulating plant species, has the potential to change the way we mine for heavy metals. Undoubtedly, such substances remain very valuable from a commercial standpoint since they are largely employed in the production of electronic gadgets and other devices. To stop mining altogether is a naïve desideratum. However, as research from the University of the Philippines Los Banos points out, hyper-accumulating plants may help us develop better green technology that makes such mining activities less detrimental for the environment.
What’s more, several researchers point to the potential that these plants have for building a defensive strategy in areas which are currently being mined for heavy metals. As for the areas where such activities have already taken place, phytoremediation can help restore a less toxic level of metals in the environment. Finally, research from the National Center for Biotechnology Information suggests that hyperaccumulators can also be used for food fortification. That’s because many of the metals they amass are essential nutrients – so, in a nutshell, phytoremediation and food fortification are two edges of the same sword.