Leaf nonstructural carbohydrate concentrations of understory woody species regulated by soil phosphorus availability in a tropical forest

Abstract

Leaf soluble sugars and starch are important components of nonstructural carbohydrates (NSCs), which are crucial for plant growth, development, and reproduction. Although there is a large body of research focusing on the regulation of plant NSC (soluble sugars and starch) concentrations, the response of foliar NSC concentrations to continuous nitrogen (N) and phosphorus (P) addition is still unclear, especially in tropical forests. Here, we used a long‐term manipulative field experiment to investigate the response of leaf NSC concentrations to continuous N and P addition (3‐, 5‐, and 8‐year fertilization) in a tropical forest in southern China. We found significant species‐specific variation in leaf NSC concentrations in this tropical forest. Phosphorus addition dramatically decreased both leaf soluble sugar and starch concentrations, while N addition had no significant effects on leaf soluble sugar and starch concentrations. These results suggest that, in plants growing in P‐limiting tropical soil, leaf NSC concentrations are regulated by soil P availability rather than N availability. Moreover, the negative relationships between NSC concentrations and leaf mass per area (LMA) revealed that NSCs could supply excess carbon (C) for leaf expansion under P addition. This was further supported by the increased structural P fraction after P fertilization in our previous study at the same site. We conclude that soil P availability strongly regulates leaf starch and soluble sugar concentrations in the tropical tree species included in this study. The response of leaf NSC concentrations to long‐term N and P addition can reflect the close relationships between plant C dynamics and soil nutrient availability in tropical forests. Maintaining relatively higher leaf NSC concentrations in tropical plants can be a potential mechanism for adapting to P‐deficient conditions.

Shifts and plasticity of plant leaf mass per area and leaf size among slope aspects in a subalpine meadow

“…study, the addition of P increased the LMA through conversion of soluble sugars into the leaf tissue to enhance leaf expansion, which was confirmed by the increased structural P fraction under the addition of P(Mo et al, 2020) since phosphorus is an important F I G U R E 6 Linear regressions between within-in species traits value and plot mean trait across 14 plots for LMA (a) and LS (b). Different colors represent regressions of different species.…”

“…( 2020 ). In their study, the addition of P increased the LMA through conversion of soluble sugars into the leaf tissue to enhance leaf expansion, which was confirmed by the increased structural P fraction under the addition of P (Mo et al., 2020 ) since phosphorus is an important component of photosynthetic complexes and cellular structures (Marschner, 2011 ).…”

“…Surprisingly, the LMA was positively related to soil P availability (Figure 4b). The possible explanation could be the results from Mo et al (2020). In their…”

Long-term snow alters the sensitivity of nonstructural carbohydrates of Syntrichia caninervis to snow cover: Based on a 7-year experiment

“…This is mainly due to an increase in soil nutrient content and microbial activity caused by snow, which drove microbial decomposition of the Surfactant of Syntrichia caninervis and provided the ability to fix and store nutrients Syntrichia caninervis, increasing the. Increased N content in the soil and plant protein synthesizing capacity promoted enzyme activities related to photosynthesis and carbon metabolism, which in turn increased soluble sugar content, facilitated water use and transport, and enhanced carbon utilization strategy (Schimel et al, 2004;Garnett et al, 2009;Mo et al, 2020;Wang et al, 2022). However, long-term double snow treatment led to a decrease in soluble sugar content and gradually attained natural levels.…”

Long-term water use efficiency and non-structural carbohydrates of dominant tree species in response to nitrogen and water additions in a warm temperate forest

“…Starch is an effective and relatively stable storage molecule that not only provides energy and sugar but also promotes plant growth ( Dietze et al., 2014 ; Schiestl-Aalto et al., 2019 ). The NSC concentration reflects the adaptability of plants to a changeable environment ( Hoch et al., 2003 ; Mo et al., 2020 ). When the NSC content is depleted, plants would face death ( Hartmann and Trumbore, 2016 ; Santos et al., 2021 ).…”