Asymmetric responses of terrestrial C:N:P stoichiometry to precipitation change

Abstract

Aim The aim was to test whether the responses of C:N:P stoichiometry in plant–soil–microorganism systems to precipitation changes support the prediction of the double asymmetry model, which predicts ecological processes (i.e. aboveground productivity, soil microbial community, and soil respiration) are more sensitive to increased precipitation (R+) than decreased precipitation (R−) under normal precipitation changes, whereas more sensitive to R− than R+ under extreme precipitation changes. Location Global. Time period 1999–2020. Major taxa studied Plants, soils, and soil microorganisms. Methods We performed a global meta‐analysis of 848 observations (587 R− and 261 R+ manipulations) from 160 studies, which tested the effects of precipitation changes on C:N:P across plants, soils, and soil microorganisms. The data encompassed broad variations in ecosystems, climate, precipitation intensity, and experimental duration. Results We revealed that the C:N and C:P ratios of different ecosystem compartments were more sensitive to moderate R+ rather than moderate R−, whereas they exhibited a higher response to extreme R− rather than extreme R+, which supported the prediction of the double asymmetry model. Moreover, such responses were more pronounced under higher precipitation intensities and longer experimental duration. The effects of precipitation changes on the C:N:P stoichiometry of plants, soils, and soil microorganisms were consistent across ecosystem types (i.e. forests and grasslands) and associated background climates (i.e. mean annual temperature and precipitation). Main conclusions Our findings provide the first evidence of the asymmetric responses of C:N:P stoichiometry in above‐ and belowground systems to precipitation change. These results extend the double asymmetric model and improve our understanding of C and N cycling, as well as facilitate the prediction of ecosystem responses to precipitation changes.

Phosphorus additions imbalance terrestrial ecosystem C:N:P stoichiometry

“…Importantly, we demonstrated P addition effects on C:N:P stoichiometry of plants, soils, and microbial biomass increased with P application rates and experimental duration (Figures 3 and 4). The results agreed with the pattern observed for the global change–ecological stoichiometry relationship observed for terrestrial ecosystems (Sun, Liao, et al, 2020; Sun, Wang, et al, 2020; Sun et al, 2021; Wang et al, 2021). It is because P limitation in the terrestrial ecosystem is aggravated over time (Peñuelas et al, 2013).…”

“…This indicates that the P addition effects on terrestrial ecosystem C:N:P stoichiometry show consistency across various ecosystems and associated climates worldwide. This agrees well with the responses of terrestrial ecosystem C:N stoichiometry toward drought (Sun, Liao, et al, 2020), N addition (Sun, Wang, et al, 2020), elevated CO 2 concentration (Wang et al, 2021), warming (Sun et al, 2022), and increased precipitation (Sun et al, 2021). Consistent with previous evidences (Peñuelas et al, 2020;Wironen et al, 2018), we found P additions decreased soil N:P ratios of croplands (Figure 5), which is likely because the manure applied is characterized by low N:P ratios (Oster et al, 2018).…”

Experimental Approach Alters N and P Addition Effects on Leaf Traits and Growth Rate of Subtropical Schima superba (Reinw. ex Blume) Seedlings

“…These results were consistent with the previous study, because plants may take up N and P in excess of growth requirements when nutrients are abundant, sustaining steady growth through periods of nutrient scarcity [50]. Similarly, the relationship between RGR and nutrient ratios was not always present for each of the marsh herbaceous plants [51]. Thus, existing relationships between leaf stoichiometry and RGR might depend on experimental approaches, and species-specific and experimental approaches should be carefully considered when using the theoretical association of tree growth rate with leaf stoichiometry.…”

Precipitation increase counteracts warming effects on plant and soil C:N:P stoichiometry in an alpine meadow

“…Water availability is critical to the productivity of grassland ecosystems, so precipitation is expected to be a key driver of ecosystem processes ( Wu et al., 2011 ). Precipitation increase provides higher moisture to the soil in the plant growing area, which promotes plant growth and alters the elemental cycle in plant, roots, and soil ( Sun et al., 2021 ). Yuan & Chen (2015) found that the increased rainfall reduced plant N:P ratio and cause a shift in the type of limiting elements for plant growth.…”

“…(2006) demonstrated that there was no significant correlation between plant leaf C and P concentrations and precipitation, which implied that it was difficult to detect the response of plant C:P ratio to short-term precipitation changes. Precipitation increase promoted plant growth, resulting in more C input to the soil from litter and roots ( Zhang and Xi, 2021 ), and promoted soil N leaching ( Chen et al., 2016 ), leading to an increase in soil C:N ratio ( Sun et al., 2021 ). Soil N:P ratio was greatly determined by nutrient uptake of plant ( Abbasi et al., 2020 ).…”