| Autor: |
Mohammed-Nour A; Department of Soil Science, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia.; Soil and Water Research Centre, Agricultural Research Corporation, P.O. Box 126, Wad-Medani 21111, Al Jazirah, Sudan., Al-Sewailem M; Department of Soil Science, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia., El-Naggar AH; Department of Soil Science, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia.; Sustainable Natural Resources Management Section, International Centre for Biosaline Agriculture (ICBA), Dubai 14660, United Arab Emirates.; Department of Soil Sciences, Faculty of Agriculture, Ain Shams University, Cairo 11241, Egypt., El-Saeid MH; Department of Soil Science, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia., Aly AA; Department of Soil Science, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia.; Soil and Water Science Department, Alexandria University, Alexandria 21545, Egypt., Elfaki J; Department of Soil Science, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia.; Faculty of Agriculture, Nile Valley University, P.O. Box 1843, Atbara 45512, River Nile State, Sudan.; Desert Farming Techniques and Agricultural Biotechnology Programs, Sultan Qaboos Chair in Desert Farming, Department of Natural Resources & Environment, Arabian Gulf University, P.O. Box 26671, Manama 323, Bahrain. |
| Abstrakt: |
In Saudi Arabia, more than 335,000 tons of cow manure is produced every year from dairy farming. However, the produced cow manure is usually added to the agricultural soils as raw or composted manure; significant nitrogen losses occur during the storage, handling, and application of the raw manure. The recovery of ammonia from cow manure through thermochemical treatments is a promising technique to obtain concentrated nitrogen fertilizer and reducing nitrogen losses from raw manure. However, the byproduct effluents from the recovery process are characterized by different chemical properties from the original raw manure; thus, its impact as soil amendments on the soil carbon and nitrogen dynamics is unknown. Therefore, a 90-day incubation experiment was conducted to study the impact of these effluents on CO 2 efflux, organic C, microbial biomass C, available NH 4 + , and NO 3 - when added to agricultural soil. In addition to the two types of effluents (produced at pH 9 and pH 12), raw cow manure (CM), composted cow manure (CMC), cow manure biochar (CMB), and control were used for comparison. The application of CM resulted in a considerable increase in soil available nitrogen and CO 2 efflux, compared to other treatments. Cow manure biochar showed the lowest CO 2 efflux. Cumulative CO 2 effluxes of cow manure effluents were lower than CM; this is possibly due to the relatively high C:N ratio of manure effluent. The content of P, Fe, Cu, Zn, and Mn decreased as incubation time increased. Soil microbial biomass C for soil treated with cow manure effluents (pH 12 and 7) was significantly higher than the rest of the soil amendments and control. |
