Contribution of Different Quantities of Leaf Litter to Nitrous Oxide Emission from a Temperate Deciduous Forest

Abstract

Leaf litter cover on forest floors regulates the nitrogen dynamics in soil and affects soil-atmospheric exchange of nitrous oxide (N2O). "The effect of 'different mass' of leaf litter on N2O" emission is, however, unclear. In this study, we measured N2O emission from variable leaf litter applications in (IN) and on (ON) soil such as 0 (control), 370, 730, and 1,009 g dry weight m(-2). Closed chambers were installed at an experimental site in Korea to measure N2O emission from the soil. Average N2O emission was decreased by 1.15 mu g N2O-N m(-2) h(-1) with leaf litter removal in ON-0 and increased by 2.38 mu g N2O-N m(-2) h(-1) with soil tilling in IN-0 treatment. Average N2O emission was increased by 3.75 mu g N2O-N m(-2) h(-1) and 3.06 mu g N2O-N m(-2) h(-1) with increasing leaf litter from 370 to 730 g m(-2) in both ON and IN treatments, respectively. N2O emission was decreased by 4.04 mu g N2O-N m(-2) h(-1) and 1.51 mu g N2O-N m(-2) h(-1) in ON-1009 and IN-1009 treatments as compare to ON-730 and IN-730 treatments, respectively due to high soil water content and carbon to nitrogen ratio, respectively. Average annual N2O emission in different types of temperate forests around the World ranged between 13.5 to 21,10.0 g N2O-N ha(-1) y(-1), while 1,007.4 g N2O-N ha(-1) y(-1) was observed in this study. Soil temperature exhibited a weak correlation with N2O emission in all treatments of both IN and ON treatments. Average N2O emission in IN-0, IN-370, IN-730, and IN-1009 was 45.0, 53.0, 27.0, and 86.0% higher than ON-0, ON-370, ON-730, and ON-1009 treatments, respectively. Results of N2O emission from this study can be used to estimate N2O emission from forest soils in Korea and extended worldwide to countries with similar soil and climatic conditions.