Leaf carbon nitrogen and phosphorus concentrations in dominant trees across China's forests from 2005 to 2020.

Carbon (C), nitrogen (N), and phosphorus (P) are fundamental elements for plant growth and metabolism. Leaf C-N-P stoichiometry provides critical insights into plant nutrient use efficiency and ecosystem-scale carbon-nutrient interactions, particularly under global change. However, comprehensive long-term records of leaf C, N, and P concentrations remain scarce. Here we compiled and publicly released the Leaf Carbon-Nitrogen-Phosphorus Concentrations in China's Forests (CNP-China) dataset, containing 628 standardized records from 52 dominant tree species across 11 representative China's forest ecosystems from 2005 to 2020. All samples were collected and analyzed following the Chinese Ecosystem Research Network (CERN) protocols, with accompanying plot-level geographic and environmental data, species taxonomy and functional traits, and surface soil properties (0-20 cm depth). The dataset underwent rigorous quality control, including unit harmonization, error checking, and outlier detection, and is provided in accessible CSV format. CNP-China enables critical assessments of stoichiometric responses to environmental change, supports improved ecosystem modeling, and facilitates cross-biome comparisons of nutrient cycling dynamics, providing an essential foundation for understanding forest carbon-nutrient feedback under global change.