Abstract: To examine the effects of site location and litter type on litter decomposition, a reciprocal decomposition experiment was conducted to study the effects of contrasting sites (urban vs. suburban) and leaf litter types (urban leaf litter vs. suburban leaf litter) on the mass loss rate and N- and P remaining percentages of Pinus tabulaeformis leaf litters when decomposing in urban stand and suburban stand, respectively. The one year experiment showed that different sites had significant effects on the decomposition rate of P. tabulaeformis leaf litters (P<0.05). The leaf litters decomposed faster at suburban site than at urban site, suggesting that environmental conditions had significant effects on the decomposition. In the same stands, different litter types had significant effects on the litter decomposition (P<0.05). The decomposition rate of the litters was faster at urban site than at suburban site, suggesting the significant effects of inherent characters of the litters. Site had no significant effects on the N-and P remaining percentages, but litter type had significant effects. Urban leaf litter, due to its higher initial C/N and C/P, were easy to enrich N and P during decomposition, as compared with suburban leaf litter.

Key words: cold-shock, high temperature stress, tomato seedlings, biomembrane protection system, small heat shock protein.