Comparison Of Leaf Litter Properties And Decomposition From Limestone Area And Sandstone Area In Chongqing

Leaf litter functional traits, nutrient resorption and litter decomposition rates of60kinds of representative plants from limestone habitats (Haishi Park) and sandstone habitats (Junyun Mountain Nature Reserve)in Chongqing were investigated,30species from each habitats type. Study on the Specific leaf area, leaf physical toughness, pH, leaf nitrogen concentration, leaf phosphorus concentration and N:P ratio of litter, correlation analysis on relationship between different traits, to reveal differences of litter functional traits from different habitats in the same climate condition. Study on nutrient concentration(including C, N, P) of green leaf and leaf litter, and nutrient resorption efficiency. Collected litter was put in nylon bag and then was put on different kinds of substrate, with sampling and weighing it every7month(a total of two times), and then calculated the decomposition rate and explored the factors effecting on the decomposition.LNC in Limestone area was less than Sandstone area(P<0.5). leaf N:P ratio in Limestone area was less than Sandstone area(P<0.001). LPC in Limestone area was higher than Sandstone area(P<0.5). pH in Limestone area was higher than Sandstone area(P<0.001). No significant difference were detected between SLA and LT in the two habitats. In Limestone area, LNC was positive correlated with LPC; LPC was negatively correlated with N:P. In Sandstone area, LNC was positive correlated with LPC, LNC was negatively correlated with N:P, LT; LPC was negatively correlated with N:P, LPC was positive correlated with pH; N:P was positive correlated with LT; SLA was positive correlated with pH.Rangeability of LCC, LNC and LPC of green leaf in the two habitats was370-499mg/g,21-48mg/g,0.43-3.0mg/g respectively, litter was371-508mg/g,18-42mg/g,0.135-2.9mg/g respectively. Average resorption efficiency of LCC, LNC and LPC was0.43%,15.81%,40.19%respectively in Limestone area, in Sandstone area it was0.08%,6.36%,33.17%respectively.Average litter decomposition rate from Limestone area(Haishi Park) was higher than Sandstone area(Junyun Mountain Nature Reserve). Decomposition rate was affected by Species, Growth Form, interaction between Species and Places which species come from, interaction between Species and Growth Form. Decomposition rate was negatively correlated with LDMC in limestone and sandstone substrate from Limestone area, also it was negatively correlated with LCC in limestone substrate from Limestone area. Decomposition rate was positive correlated with LNC, LPC, SLA and pH in sandstone substrate from Sandstone area, also it was positive correlated with LNC and pH in limestone substrate from Sandstone area.