Litter Dynamics and Nutrient Stocks in a Chronosequence of Hyperxerophilous Forest Under the Effect of Clear Felling

Clear-cutting disrupts forest structure, alters litter accumulation, and impairs nutrient cycling in dry forest ecosystems. This study evaluated the effects of clear-cutting on litter and nutrient stocks in hyperxerophilous Caatinga in northeastern Brazil in areas under different regeneration stages (0, 6, 9, 12, 25, 50 years, and a reference site) in northeastern Brazil. Stocks and concentrations of total carbon (TC), total nitrogen (TN), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) were measured. Statistical analyses included Generalized Linear Models (GLM) with gamma distribution, MANOVA for multivariate comparisons, Principal Component Analysis (PCA) to identify structural gradients, and hierarchical cluster analysis to classify lignocellulosic profiles. Results showed that clear-cutting substantially reduces litter and nutrient stocks, particularly N and P, and increases the TC/TN ratios-especially in the litter-negatively affecting litter accumulation. After 50 years, regeneration had not restored pre-disturbance levels. Litter biomass was functionally associated with soil P, Ca, and S. PCA revealed two main gradients: one axis of recalcitrance (related to FDA, cellulose, and NDF) and one axis of lignin-cellulose complexity, which discriminated materials with different decomposition potentials. Multivariate analyses revealed gradients linked to recalcitrance and litter decomposition potential. These findings indicate that the TC/TN ratio and nutrient availability regulate litter persistence and ecosystem resilience. Enrichment planting with species having lower TC/TN ratios, green manuring, and biodiversity restoration are recommended to improve litter quality, accelerate nutrient cycling, and promote recovery of ecosystem functions in drylands.