Ecological stoichiometry of C, N, P and Si of Karst Masson pine forests: Insights for the forest management in southern China

• Published in: The Science of the total environment 2024-02, Vol.912, p.169490-169490, Article 169490
• Main Authors: Gong, Zhijian, Sheng, Maoyin, Zheng, Xujuan, Zhang, Ying, Wang, Linjiao
• Format: Article
• Language: English
• Subjects: Ecological stoichiometry; Karst; Masson pine; Nutrient cycle; Silicon
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2023.169490

Ecological stoichiometry is an effective method to study the stoichiometric relations and laws of elements in biogeochemical cycle, widely used in studies on nutrient cycles, limiting elements and nutrient utilization efficiency in ecosystems. To explore C, N, P, and Si stoichiometric characteristics and reveal these nutrient cycle processes and mechanisms in the karst Masson pine forests, the typical Masson pine forests of the three different stand ages in southern China were selected as the research objects and the C, N, P, and Si stoichiometric characteristics of soil-plant-litter continuum were studied. The followed results and conclusions were obtained: 1) Content range of TOC (total organic carbon), TN (total N), TP (Total P) and TSi (total Si) of the Masson pine forests was 288.31–334.61, 0.34–6.66, 0.11–1.05, and 0.76–11.4 g·kg−1, respectively. And the ratio range of C:N, C:P, C:Si, N:P, N:Si, and P:Si was 49.95–913.57, 99.98–2872.18, 22.48–429.31, 1.85–6.33, 0.17–6.01, and 0.04–0.91, respectively. 2) The significant differences in C, N, P, and Si stoichiometric characteristics were present between different organs or different forest ages. Leaves had the highest N and P content, while roots were the best enriched organ of Si element. Si content and C:Si were obviously correlated with forest age. 3) Significant N limitation was present in the Masson pine forests. And in the young and middle-aged forests, N limitation was more obvious. 4) The litter nutrients mainly came from branches. And the litter decomposed fast, which played an important role in the nutrient return of barren karst soil. The present results not only revealed the stoichiometric characteristics and cycling processes of C, N, P, and Si elements in the Masson pine forests, but also provided important scientific bases for the artificial management of Masson pine plantations in southern China. [Display omitted] •Si stoichiometric characteristics with C, N, P of Masson pine forest was reported.•Cycles of C, N, P and Si nutrients in the Masson pine forests were clarified.•Si content and C:Si were reliable ecological indicators for forest age.•Significant N limitation was present in the Masson pine forests.•Fast litter decomposition is great significance for the forest nutrient cycles.