Compost and soil moisture effects on seasonal carbon and nitrogen dynamics, greenhouse gas fluxes and global warming potential of semi‑arid soils

International Journal of Recycling Organic Waste in Agriculture

مقاله 38، دوره 8، Supplement، اسفند 2019، صفحه 367-376   

شناسه دیجیتال (DOI): 10.1007/s40093-019-00309-4

نویسندگان

Mavis Badu Brempong^{1، 2}؛ Urszula Norton^{2، 3}؛ Jay B. Norton⁴

¹Present address: Crop Research Institute, Fumesua, P.O. Box 3785, Kumasi, Ghana

²Department of Plant Sciences, University of Wyoming, Dept. 3354, 1000 East University Avenue, Laramie, WY, 82071, USA

³Program in Ecology, University of Wyoming, Laramie, WY, 82071, USA

⁴Department of Ecosystem Science and Management, University of Wyoming, Dept. 3354, 1000 East University Avenue, Laramie, WY, 82071, USA

چکیده

Purpose An 8-week incubation study was conducted to monitor soil inorganic nitrogen (N), dissolved organic carbon (DOC), greenhouse gases (GHG) [CO₂, N₂O and CH₄] and cumulative global warming potential (GWP) in dryland soil.
Method Soil was amended with variable rates of compost (zero, 15, 30 and 45 dry Mg ha⁻¹) and soil moistures [5% (dry), 7% (normal) and 14% (wet) water filled pore space (WFPS)] and experienced biweekly temperature transitions from 5 °C (late winter) to 10 °C (early spring) to 15 °C (late spring) to 25 °C (early summer).
Results The addition of 30 and 45 Mg ha⁻¹ compost enhanced N mineralization with 13% more soil inorganic N (7.49 and 7.72 µg Ng⁻¹ day⁻¹, respectively) during early summer compared with lower compost rates. Normal and wet soils had 35% more DOC in the late spring (an average of 34 µg g⁻¹ day⁻¹) compared to the dry WFPS, but transitioning from late spring to early summer, DOC at all soil WFPS levels increased. Highest rates of compost were not significant sources of GHG with normal soil WFPS, compared with lower compost rates. Carbon dioxide emissions increased by 59 and 15%, respectively, as soil WFPS increased from dry to normal and normal to wet. Soils with normal WFPS were the most effective CH₄ sink.
Conclusion One-time application of high compost rates to dryland soils leads to enhanced N and C mineralization under normal soil moisture and warmer temperature of the summer but will not pose significant global warming dangers to the environment through GHG emissions since soils are rarely wet.

کلیدواژه‌ها

Dryland soil؛ Compost؛ Nutrient mineralization؛ Greenhouse gas emission