English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Increases in nitrogen (N) deposition can greatly stimulate\udecosystem net carbon (C) sequestration through positive N-induced effects on\udplant productivity. However, how net ecosystem CO2 exchange (NEE) and\udits components respond to different N addition rates remains unclear. Using an N addition gradient experiment (six levels: 0, 2, 4, 8, 16,\ud32 gN m−2 yr−1) in an alpine meadow on the Qinghai–Tibetan\udPlateau, we explored the responses of different ecosystem C fluxes to an N\udaddition gradient and revealed mechanisms underlying the dynamic responses.\udResults showed that NEE, ecosystem respiration (ER), and gross ecosystem\udproduction (GEP) all increased linearly with N addition rates in the first\udyear of treatment but shifted to N saturation responses in the second year\udwith the highest NEE (−7.77 ± 0.48 µmol m−2 s−1) occurring under an N\udaddition rate of 8 gN m−2 yr−1. The saturation responses of NEE\udand GEP were caused by N-induced accumulation of standing litter, which\udlimited light availability for plant growth under high N addition. The\udsaturation response of ER was mainly due to an N-induced saturation response of\udaboveground plant respiration and decreasing soil microbial respiration along\udthe N addition gradient, while decreases in soil microbial respiration under\udhigh N addition were caused by N-induced reductions in soil pH. We also found\udthat various components of ER, including aboveground plant respiration, soil\udrespiration, root respiration, and microbial respiration, responded\uddifferentially to the N addition gradient. These results reveal temporal\uddynamics of N impacts and the rapid shift in ecosystem C fluxes from N\udlimitation to N saturation. Our findings bring evidence of short-term initial\udshifts in responses of ecosystem C fluxes to increases in N deposition, which\udshould be considered when predicting long-term changes in ecosystem net C\udsequestration

Initial shifts in nitrogen impact on ecosystem carbon fluxes in an alpine meadow: patterns and causes