Nitrous oxide and methane emissions from grassland treated with bark- or sawdust-containing manure at different rates

Abstract

On the main Japanese island of Honshu, bark or sawdust is often added to cattle excreta as part of the composting process. Dairy farmers sometimes need to dispose of manure that is excess to their requirements by spreading it on their grasslands. We assessed the effect of application of bark-or sawdust-containing manure at different rates on annual nitrous oxide (N 2 O) and methane (CH 4 ) emissions from a grassland soil. Nitrous oxide and CH 4 fluxes from an orchardgrass (Dactylis glomerata L.) grassland that received this manure at 0, 50, 100, 200, or 300 Mg ha À1 yr À1 were measured over a two-year period by using closed chambers. Two-way analysis of variance (ANOVA) was employed to examine the effect of annual manure application rates and years on annual N 2 O and CH 4 emissions. Annual N 2 O emissions ranged from 0.47 to 3.03 kg N ha À1 yr À1 and increased with increasing manure application rate. Nitrous oxide emissions during the 140-day period following manure application increased with increasing manure application rate, with the total nitrogen concentration in the manure, and with cumulative precipitation during the 140-day period. However, manure application rate did not affect the N 2 O emission factors of the manure. The overall average N 2 O emission factor was 0.068%. Annual CH 4 emissions ranged from À1.12 to 0.01 kg C ha À1 yr À1. The annual manure application rate did not affect annual CH 4 emissions.

The succession pattern of bacterial diversity in compost using pig manure mixed with wood chips analyzed by 16S rRNA gene analysis

“…The fundamental reason for using various additives in composting processes is to provide the best-growing environment for microbial growth and achieve rapid composting, thus reducing the harmful gas emissions under controlled conditions. For example, sawdust is an additive that reduces methane emissions to a certain extent [4]. However, the quality of the fertilizer ultimately depends on the microbial composition of the compost, and only a clear understanding of the succession pattern of the microbial communities throughout the composting stages will enable us to fully control this process.…”

The effect of fertilizer and manure application on CH4and N2O emissions from managed grasslands in Japan

“…Akiyama and Tsuruta (2003) reported that N 2 O emissions were 0.08% and 0.05% of applied N for dried cattle excreta (C/N rate of 24.3) and for cattle manure (C/N rate of 15.9), respectively. Mori and Hojito (2011) reported that manure-induced EF of bark-or sawdust-containing manures was 0.068% in orchard grassland in Tochigi. These values are relatively smaller than manure-induced EF in our study.…”

“…Therefore, annual N 2 O emissions have spatial and/or inter-annual variation due to the variations in soil and climate (Lu et al 2006;Gu et al 2007;Gu et al 2009;Mori and Hojito 2012). Furthermore, the application of chemical N fertilizer and livestock manure could augment N 2 O emissions, and N 2 O emissions can be affected by fertilizer type (Bouwman et al 2002a;Akiyama and Tsuruta 2003;Akiyama et al 2006;Mori and Hojito 2011). Manure with a high and easily mineralizable organic C content stimulates microbial activity and thus N 2 O emissions (Drury et al 1991;Chadwick et al 2000).…”

Greenhouse Gas Sink-Source Functions of Grassland Ecosystems

“…The N 2 O EF of synthetic fertilizer (0.1%-5.7%) increases with increasing annual mean air temperature (5.2-15.8°C) and precipitation (1160-2595 mm year −1 ), but the N 2 O EF of FYM (−3.2% to +1.3%) has shown no clear relationships (Shimizu et al 2013). The smaller N 2 O EF for FYM is due mainly to less inorganic N in FYM as compared with synthetic fertilizer (Mori and Hojito 2011). The background N 2 O emissions (0.2-4.2 kg N ha −1 year −1 ) also increase with increasing temperature and precipitation.…”