Organic and chemical processes in rainforests are important for the best way these ecosystems maintain onto vitamins, but lots of the particulars are nonetheless unclear. One vital query is what occurs to nitrite, shaped by means of the transformation of nitrate, a really reactive type of nitrogen that often doesn’t final lengthy in soils. It has usually been assumed that solely microbes management what occurs to nitrite. Nevertheless, new outcomes present that chemical reactions on their very own—with out the assistance of residing organisms—can even lock nitrite into the soil by attaching it to natural supplies, which is the pure matter shaped from decayed vegetation and animals. This hidden course of could also be one of many keys to why rainforest soils stay fertile regardless of heavy rainfall.
Professor Francisco Matus from Universidad de La Frontera led a crew of scientists to examined this query carefully. Their findings have been printed within the journals Forests and Journal of Environmental Administration, scientific publications devoted to research of forest ecosystems.
Utilizing a protected chemical label known as isotopic labelling, which permits scientists to comply with how components transfer, the crew studied soils from each volcanic areas and non-volcanic landscapes in rainforests. After they eliminated oxygen from the setting, creating an oxygen-free or anoxic situation, they noticed that nitrate, and particularly nitrite added shortly start to vanish. Inside a really brief time, practically half of it was gone, and over a number of days, a lot of it had been was a type of natural nitrogen, first dissolved within the soil water after which included into strong natural matter changing into a part of a secure pool that’s much less vulnerable to fast loss however essential for long-term fertility. In reality, near three-quarters of the nitrite was held in natural matter, whatever the origin of the soil.
What stood out most was that the quantity of nitrate and nitrite added to the soil mattered greater than the type of rock the soil initially got here from. Put merely, how a lot nitrite entered the system decided how a lot was stored in natural kind. As Professor Matus defined: “These outcomes present that a big share of the added nitrate reworked to nitrite might be abiotically included into the DON and SON of unpolluted old-growth temperate rainforest, whether or not developed on volcanic or non-volcanic soils”. Right here DON and SON refers to dissolved and strong natural nitrogen, that means nitrogen that’s combined into the water and hooked up to elements throughout the soil natural kind.
One other key perception is that rainforests often lose nitrogen not in its free mineral kind, however certain along with natural supplies. This new proof means that soils can entice nitrite transformed from nitrate by means of pure chemical reactions, lowering the lack of vitamins from the ecosystem. In keeping with Professor Matus, this resilience exhibits that the quantity of natural matter accessible within the soil is extra vital for stabilizing nitrogen than the kind of soil derived from the guardian rock.
Past the rainforests themselves, these discoveries add vital data to how we perceive the worldwide nitrogen cycle, which is the motion of nitrogen between the air, soil, vegetation, and water. In moist forests, vitamins are sometimes washed away sooner than in drier areas, however this chemical pathway helps clarify why a lot nitrogen shouldn’t be misplaced in its mineral kind. The researchers additionally spotlight the “Ferrous Wheel Speculation,” an concept that iron within the soil helps recycle nitrogen into natural types, giving rainforests one other strategy to retain their vitamins even below heavy rainfall.
Total, Professor Matus’s research highlights that chemical reactions, not simply microbes, are important in conserving rainforests wholesome and fertile. As he summarized: “This reveals the pure resilience of unpolluted temperate rainforests to nitrogen loss, with implications for long-term ecosystem stability and nutrient biking”.
Journal Reference
Matus F., Dyckmans J., Inventory S.C., Merino C., Dippold M.A., Kuzyakov Y. “Abiotic Nitrite Incorporation into Natural Matter in Volcanic and Non-Volcanic Soil Inside Rainforest Ecosystems.” Forests, 2025; 16(930). DOI: https://doi.org/10.3390/f16060930
Matus, F., Álvarez, E., Godoy, R., Iturriaga-Vásquez, P., Farías-Cea, A., Parada, J., Merino, C., Nájera, F., Mendoza, D., Jofré, I., Knicker, H., Dippold, M. A., Kuzyakov, Y., Schluesselburg, L., Boy, J. “Ferrous wheel speculation II: Abiotic incorporation of mineral nitrogen into natural swimming pools in volcanic soils of temperate forest ecosystems.” Journal of Environmental Administration, 2025 391 (126311). DOI: https://doi.org/10.1016/j.jenvman.2025.126311
Concerning the Writer
Professor Francisco J. Matus is an Agronomist with a Grasp’s diploma from the Pontificia Universidad Católica de Chile and a Ph.D. from Wageningen College within the Netherlands. His experience lies in plant diet, soil fertility, and environmental sciences. In 2009, he was invited to hitch a analysis undertaking aimed toward enhancing nitrogen use effectivity in cropping programs as a Postdoctoral Fellow on the Division of Chemistry, Carleton College, and Agriculture and Agri-Meals Canada. His analysis focuses on soil nutrient dynamics and conservation in volcanic soils, nitrogen use effectivity, and carbon sequestration in each agricultural and pure ecosystems. Professor Matus has in depth expertise within the biogeochemistry of carbon and nitrogen biking in pristine forest ecosystems and excessive environments equivalent to Antarctic soils. In 2017, he was invited by the Division of Agricultural Soil Science at Georg-August College, Göttingen (Germany), to work on abiotic processes concerned in soil natural carbon oxidation. He additionally specializes within the software of secure isotopes on the rhizosphere degree and using crop simulation fashions. He maintains a robust collaborative community with analysis teams in Europe, the USA, Canada, and New Zealand. Professor Matus presently serves as Director of the Ph.D. Program in Pure Sources Sciences and Director of the Laboratory of Conservation and Dynamics of Volcanic Soils at Universidad de La Frontera.
