糖心视频

The idea of trees "talking" to one another through underground fungal networks鈥攖he so-called "wood wide web"鈥攈as captured the imagination of the public. This concept, where trees supposedly share nutrients with each other via these networks, has been popularized by books and documentaries.

But a new study, led by the University of G枚ttingen, suggests the reality might be more nuanced. The researchers found that young beech trees could transfer carbon to nearby "ectomycorrhizal" fungi鈥攁 kind of fungi that grows on and together with the tree roots in a beneficial relationship鈥攂ut not to other trees.

These fungi form intricate underground connections with tree roots, and it has been suggested they might also connect trees to each other, allowing for mutual nutrient exchange. However, this latest research raises questions about how much actual sharing is going on. The findings were in New Phytologist.

To trace the movement of carbon, the scientists used a technique called isotopic labeling. They provided CO₂ enriched with a heavier carbon isotope (known as Carbon-13) to a young "donor" beech tree and waited five days, giving the tree time to absorb and move the Carbon-13 to its roots. Then, they measured the carbon in the roots, stems, and leaves of a nearby potential "recipient" tree.

Ectomycorrhizal roots鈥攖he roots symbiotically associated with these fungi鈥攚ere of particular interest to the researchers; with a delicate surgical intervention, they separated the plant-tissue from the fungus-colonized-tissue of the root tips and found that Carbon-13鈥攖he marker for donor-derived carbon鈥攚as only in the fungus-colonized tissue and not in the rest of the roots of the recipient tree. They repeated the experiment on Douglas firs and again found that the Carbon-13 was only in fungus-colonized tissue, albeit in smaller amounts in this species.

"These findings add fuel to a long-standing debate in ecology: are trees truly interconnected in a cooperative way?" explained postdoctoral researcher, Dr. Michela Audisio, at G枚ttingen University's Department of Forest Botany and Tree 糖心视频iology. She added, "It is hard to imagine that ectomycorrhizal fungi would altruistically transfer carbon from one tree to another. However, there are likely to be advantages for the fungi if can access multiple carbon sources, especially when facing environmental stress."

The study also explored what these findings mean for German forests more broadly. The researchers found that ectomycorrhizal roots of Douglas fir, a non-native species, received slightly less of the labeled carbon than European beech, a native species. "This could mean that in forests mixed with Douglas fir, ectomycorrhizal fungi may be less abundant," said Audisio, "Potentially affecting the forest's carbon cycle."