Phosphorus addition affects soil nitrogen dynamics in a nitrogen‐saturated and two nitrogen‐limited forests

Abstract

Phosphorus (P) availability can affect nitrogen (N) dynamics in forest soil, and this effect might depend largely on the soil N status of forest ecosystems. So far, however, this view has not been well tested among forests with contrasting N status. Here, we used a 6‐year experiment with additions of N and P to evaluate the effects of P availability and its interaction with N availability on soil N dynamics in one N‐saturated and two N‐limited tropical forests in southern China. Soil inorganic N concentrations and rates of N mineralization, nitrification, nitrous oxide (N2O) emission and nitrate leaching were measured. Our results showed that addition of P alone changed soil N dynamics in the N‐saturated forest only; it accelerated rates of soil N transformation and decreased rates of N2O emission and nitrate leaching, but had no significant effects on N dynamics in the two N‐limited forests. Furthermore, compared with the addition of N alone, addition of both N and P caused significant increases in the rates of net N mineralization and nitrification and a significant decrease in N2O emission in the two N‐limited forests. Our results suggest that P availability stimulates soil N dynamics only when the ecosystem is saturated with N or there is considerable N deposition. Highlights We compared the effects of P addition on soil N dynamics among forests with different N status. Addition of P alone changed N dynamics in the N‐saturated forest, but not in N‐limited forests. Combined N and P additions had a larger effect on N dynamics than N addition alone. Phosphorus addition affects N dynamics only when an ecosystem has considerable N status.

Fate of nitrogen in agriculture and environment: agronomic, eco-physiological and molecular approaches to improve nitrogen use efficiency

“…The response of crop yield might be affected directly or indirectly [72,73]. Therefore, the supply of both N and P creat changes in chemical, physical, and biological properties of soil [74,75]. The nitrogen fertilizer has synergetic effect to phosphorus.…”

Phosphorus Supply Increases Nitrogen Transformation Rates and Retention in Soil: A Global Meta‐Analysis

“…Phosphorus addition can affect soil N pools and cycling processes in a variety of ways via different impacts on plant growth and microbial activity (Turner & Wright, 2014). For instance, addition of P decreased N leaching losses and retained more N in plant‐soil ecosystems by promoting plant and microbial growth and N uptake (e.g., Baral et al., 2014; Chen et al., 2017), but it could also increase loss of N through gaseous emissions, such as N 2 O, by stimulating nitrification and/or denitrification processes (Mehnaz, Corneo et al., 2019; Mori et al., 2013). However, reductions in N 2 O emissions were also found in P‐limited ecosystems because of a decline in NO 3 − availability and denitrification (Chen et al., 2016; Mori et al., 2014; Yu et al., 2017).…”

Organic and Inorganic Nitrogen forms as Affected by Phosphorus Additions in a Maize–Mustard Cropping System

“…[12] Moreover, P applied to soils enhances production of pyridoxal phosphate and promotes aminotransferase activity, accelerating rates of inorganic N forms turnover and organic N forms mineralization. [13] However, some recent studies have shown that phosphate application to the soils has little effect on the bioavailability of soil N [14] or limits the mineralization of organic N. [15] Therefore, the roles of the phosphate fertilization in soil N forms turnover are not fully understood. Furthermore, apart from phosphate addition, tillage and crops are other major factors impacting soil N forms turnover.…”