Litter decomposition rate and nutrient dynamics of giant ragweed (Ambrosia trifida L.) in the non-native habitat of South Korea

Abstract

Aim Ambrosia trifida L. is designated as an invasive exotic plants in South Korea. Despite its widespread distribution in South Korea, research on A. trifida is limited. Organic matter input by A. trifida litter decomposition is predicted to change the soil environment. In this study, we investigated the effects of A. trifida litter decomposition on soil nutrient status. Methods We used the litterbag method to investigate the decomposition rate, decay constant (k), carbon/nitrogen (C/N) ratio, and nutrient dynamics of A. trifida litter during decomposition. Results The decay constants (k) of leaf, stem, and root litter after 11 months of decomposition were 1.93, 1.47, and 1.28, respectively. After 22 months of decomposition, the decay constants (k) of leaf, stem, and root litter were 1.01, 0.99 and 1.84, respectively. After 22 months, approximately 85% of organic matter, 79% of nitrogen (N), 98% of phosphorus (P), 96% of potassium (K), 96% of magnesium (Mg), and 69% of calcium (Ca) were returned to the soil. Conclusion Our results provide key insights into the nutrients exchange between A. trifida and soil. Given the biological characteristics of A. trifida, the input of a large amount of organic matter to the soil and the nutrients released through the decomposition of this organic matter are expected to enhance the growth and nutrient absorption of A. trifida in invaded areas.