sj-docx-1-ijm-10.1177_02557614231197904 – Supplemental material for Exploring the career development issues of young musicians through participation in music festivals: A case study of the Youth Music Culture Guangdong Festival

Supplemental material, sj-docx-1-ijm-10.1177_02557614231197904 for Exploring the career development issues of young musicians through participation in music festivals: A case study of the Youth Music Culture Guangdong Festival by Yahan Chen in International Journal of Music Education</p

Standardized major axis regression for N or P resorption efficiency (NRE or PRE, NuRE) <i>vs</i> green-leaf N:P ratio for (a) all species; (b) deciduous broadleaf species (DB); (c) evergreen broadleaf species (EB); and (d) conifers.

<p>The blue symbols and lines denote NRE, and the red ones represent PRE. Regression lines of NRE vs N:P are not shown in panel (c) and (d) for lack of significant correlations between the two variables in EB and conifers (<i>p</i> = 0.76 and 0.27, respectively).</p

Standardized major axis regression (solid lines) for relative resorption efficiency (NRE - PRE) vs green-leaf N:P ratio for (a) all species, black lines; (b) deciduous broadleaf species (DB), brown dots and lines; (c) evergreen broadleaf (EB), green dots and lines; (d) conifers and N-fixing species, respectively blue and red dots and lines.

<p>The horizontal dash lines indicate where NRE equals PRE, and the vertical dash lines display the corresponding N:P ratios.</p

Figure 5. Standardized major axis regression (solid lines) for the relative resorption efficiency (NRE - PRE) <i>vs.</i> green-leaf N:P ratio across different vegetation-types globally.

<p>Data of boreal and temperate forests in China come from the authors’ unpublished data.</p

Relationship between the Relative Limitation and Resorption Efficiency of Nitrogen <i>vs</i> Phosphorus in Woody Plants

<div><p>Most previous studies have ascribed variations in the resorption of a certain plant nutrient to its corresponding environmental availability or level in tissues, regardless of the other nutrients’ status. However, given that plant growth relies on both sufficient and balanced nutrient supply, the nutrient resorption process should not only be related to the absolute nutrient status, but also be regulated by the relative limitation of the nutrient. Here, based on a global woody-plants dataset from literature, we test the hypothesis that plants resorb proportionately more nitrogen (or phosphorus) when they are nitrogen (or phosphorus) limited, or similar proportions of nitrogen (N) and phosphorus (P) when co-limited by both nutrients (the relative resorption hypothesis). Using the N:P ratio in green foliage as an indicator of nutrient limitation, we found an inverse relationship between the difference in the proportionate resorption of N <i>vs</i> P and this foliar N:P ratio, consistent across species, growth-forms, and vegetation-types globally. Moreover, according to the relative resorption hypothesis, communities with higher/lower foliar N:P (more likely P/N limited) tend to produce litter with disproportionately higher/lower N:P, causing a worsening status of P/N availability; this positive feedback may somehow be counteracted by several negative-feedback mechanisms. Compared to N, P generally shows higher variability in resorption efficiency (proportion resorbed), and higher resorption sensitivity to nutrient availability, implying that the resorption of P seems more important for plant nutrient conservation and N:P stoichiometry. Our findings elucidate the nutrient limitation effects on resorption efficiency in woody plants at the global scale, and thus can improve the understanding of nutrient resorption process in plants. This study also suggests the importance of the foliar N:P ratio as a key parameter for biogeochemical modeling, and the relative resorption hypothesis used to deduce the critical (optimal) N:P ratio for a specific plant community.</p> </div

Relationship between senesced-leaf N/P (uncorrected, in log-scale) and green-leaf N:P ratio.

<p>The three zones (I/II/III, delimitated by horizontal red lines) of senesced-leaf N and P [4] are: < 7 mg g^-1 (zone I, complete resorption) and > 10 mg g^-1 (zone III, incomplete resorption) for N (a); < 0.5 mg g^-1 or < 0.4 mg g^-1 (zone I, complete resorption for deciduous and evergreen species, respectively) and > 0.8 mg g^-1 or > 0.5 mg g^-1 (zone III, incomplete resorption for deciduous and evergreen species, respectively) for P (b). Zones II are intermediate resorption ranges in both panels. The red and green points and Roman numbers indicate the data and zones for deciduous and evergreen species, respectively. The blue points denoting conifers were also shown.</p

Standardized major axis regression (solid lines) for log₁₀-transfromed N:P ratio in senesced against green leaves of (a) all species, (b) deciduous (DB) and (c) evergreen (EB) angiosperms, and (d) conifers.

<p>The dash lines denote the 1:1 lines, above and below which the numbers of data points are shown.</p

Elevation, mean annual temperature (MAT) and soil properties of the experimental sites.

<p>STN = soil total N; STC = soil total C; STP = soil total P. Values of STN, STC, STP are expressed as mean with standard error (SE) in the parentheses of three samples.</p><p>^a Values with the same letter in a column are not significantly different (Turkey multiple comparison test; <i>p</i>> 0.05).</p><p>Elevation, mean annual temperature (MAT) and soil properties of the experimental sites.</p

Effects of species, community type and N addition rate and their interaction on N concentrations in green ([N]_g) and senescent leaves ([N]_s) and N resorption efficiency (NRE) in the shrubland communities of Mt. Dongling.

<p>N, N addition treatment; Sp, Species; Ct, Community type.</p><p>Effects of species, community type and N addition rate and their interaction on N concentrations in green ([N]_g) and senescent leaves ([N]_s) and N resorption efficiency (NRE) in the shrubland communities of Mt. Dongling.</p

Responses of mean N resorption efficiency (NRE) to N addition for seven dominant species in the <i>Vitex negundo</i> (a) and <i>Spirea trilobata</i> (b) communities.

<p>Error bars indicate standard deviation (n = 6). Different letters on the error bars indicate significant differences among treatments for each species based on one-way ANOVA. Error bars indicate standard deviation (n = 6). Different letters on the error bars indicate significant differences among treatments for each species based on one-way ANOVA.</p