Effects of Turning Frequency on Ammonia Emission during the Composting of Chicken Manure and Soybean Straw

Here, we investigated the impact of different turning frequency (TF) on dynamic changes of N fractions, NH3 emission and bacterial/archaeal community during chicken manure composting. Compared to higher TF (i.e., turning every 1 or 3 days in CMS1 or CMS3 treatments, respectively), lower TF (i.e., turning every 5 or 7 days in CMS5 or CMS7 treatments, respectively) decreased NH3 emission by 11.42–18.95%. Compared with CMS1, CMS3 and CMS7 treatments, the total nitrogen loss of CMS5 decreased by 38.03%, 17.06% and 24.76%, respectively. Ammonia oxidizing bacterial/archaeal (AOB/AOA) communities analysis revealed that the relative abundance of Nitrosospira and Nitrososphaera was higher in lower TF treatment during the thermophilic and cooling stages, which could contribute to the reduction of NH3 emission. Thus, different TF had a great influence on NH3 emission and microbial community during composting. It is practically feasible to increase the abundance of AOB/AOA through adjusting TF and reduce NH3 emission the loss of nitrogen during chicken manure composting.

Different Effects of Thermophilic Microbiological Inoculation With and Without Biochar on Physicochemical Characteristics and Bacterial Communities in Pig Manure Composting

This study evaluated the effects of thermophilic microbiological inoculation alone (TA) and integrated with biochar (TB) on the physicochemical characteristics and bacterial communities in pig manure (PM) composting with wheat straw. Both TA and TB accelerated the rate of temperature increase during the PM composting. TA significantly reduced total nitrogen loss by 18.03% as opposed to TB which significantly accelerated total organic carbon degradation by 12.21% compared with the control. Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria were the major phyla in composting. Variation of the relative abundance of genera depended on the composting period and treatment. The genera Lactobacillus (26.88–46.71%) and Clostridium_sensu_stricto (9.03–31.69%) occupied a superior position in the temperature rise stage, and Bacillus (30.90–36.19%) was outstanding in the cooling stage. Temperature, total nitrogen (TN), and ammonium nitrogen significantly influenced the bacterial phyla composition. TN, water content, and nitrite nitrogen were the main drivers of the bacterial community genera. Furthermore, our results demonstrated that microbiological consortia were resistant to high temperatures and could fix nitrogen for enriched Pseudomonas; however, when interacted with biochar, total organic carbon (TOC) degradation was accelerated for higher bacterial richness and diversity as well as overrepresented Corynebacterium.

KEHILANGAN NITROGEN PADA SISTEM USAHATANI JAGUNG MANIS DI LAHAN GAMBUT KALIMANTAN TENGAH (Nitrogen Lost on Sweet Corn Of Peatland Farming System in Central Kalimantan)

ABSTRACTApplication of fertilizer can increase nitrogen loss in agricultural land in the form of leaching andvolatilization. Research carried out on peat soil, done two times planting. First in the dry season totransition with nitrogen input from urea fertilizer, cow dung manure and from rainfall. Both areimplemented in the month of transition to the rainy season with nutrient input from nitrogen derivedfrom pearl NPK fertilizer, chicken manure and rainfall. Nitrogen washing is obtained frompercolation water which is accommodated by lysimeter. The volume of percolation water measuredat plant age 15, 30, 45 HST and at harvest, N content in laboratory analysis. The purpose of thisresearch is to know total nitrogen loss and efficiency level of sweet corn farming system inpeatland. Nitrogen washing in the first study was 2.28 kg N ha-1 or 2.49% and in the second studywas 8.95 kg N ha-1 or 13.65%. The other estimated loss of volatilization in the first study was 12.80Kg N ha-1 or 13.97% and in the second study it was 6.76 Kg N ha-1 or 10.31%. Average lossestimated volatilization of 9.78 kg N ha-1 or 12.45% Total nitrogen loss of 19.60%, so that sweetcorn farming system on peatlands in Kalampangan Urban Palangkaraya is classified as inefficientKeywords: Nitrogen, Sweet Corn, Peat Land

Forecasting N2O emission and nitrogen loss from swine manure composting based on BP neural network

Nitrogen loss and greenhouse gas emission during compost will cause secondary pollution and waste nutrients. To address this issue, a predictive model was set up to obtain a clear knowledge of the N2O emission and nitrogen loss from swine manure composting. This paper collected 68 group data from 11 published papers about pig manure composting N2O emission and total nitrogen loss. Select 4 indexes were taken as predicted indexes include aeration rate, moisture content, C/N, and the amount of superphosphate to establish a BP neural network for forecasting the N2O emission and total nitrogen loss from composting. The analyses show that the mean error of N2O emission forecasting model is 1.17; the value of MAPE is 138.85%. As for nitrogen loss, the mean error is 24.72 and the mean absolute percentage error is 11.06%. Compare to the traditional linear regression, the BP neural network model has good accuracy on forecasting N2O emission and TN loss from manure composting. BP neural network has considerable application prospect in forecast nitrogen loss and greenhouse gas emission from composting.