nitrogen-cycle
The nitrogen cycle describes how nitrogen moves through the atmosphere, soil, and living organisms via processes like fixation, ammonification, nitrification, and denitrification, transforming it into forms plants can absorb. Since nitrogen is a key building block of chlorophyll, amino acids, and nucleic acids, plant growth and productivity are directly tied to how efficiently this element is cycled and made available in the soil. Understanding these pathways helps researchers improve crop yields, manage fertilizer use, and study plant-microbe symbioses such as those with nitrogen-fixing bacteria.
open_in_new WikipediaPubMed · 2026-07-14
Alpine grassland soils use microbial nitrogen processing to lock away small amounts of CO2, but this natural carbon capture is highly vulnerable to climate swings: warming boosts it while drought nearly shuts it down, and the process barely dents the potent greenhouse gas it releases as a byproduct.
Warming increased microbial CO2 fixation rates to 1.48-2.58 times the level seen at 15°C under moist conditions
Drought reduced CO2 fixation by 59-91%, and captured carbon offset only 1.3-12.1% of associated N2O emissions (as CO2 equivalents)
Ammonia-oxidizing archaea showed the strongest carbon uptake under combined warming and drought and were the most connected group in microbial co-occurrence networks