Nitrogen immobilization in decaying hardwood leaf litter as a function of initial nitrogen and lignin content

Equations presented in an earlier paper, expressing organic matter and nitrogen dynamics in decomposing hardwood leaf litter, are extended to predict nitrogen immobilization patterns in litters of varying initial lignin and nitrogen content. A continuum of immobilization rates coincides with the successional status of the six northern hardwood species examined, with early successional species exhibiting the fastest rates. By using data from the literature, similar trends were found for southeastern hardwoods. Patterns for important species from Douglas-fir forests of the Pacific Northwest are quite different and may reflect differences in nitrogen availability following disturbance.