Kum Christian Tegha, Ngwabie N Martin, Tening Aaron Suh, Tsamo Cornelius
Department of Agricultural and Environmental Engineering, College of Technology, The University of Bamenda, P.O. Box 39 Bambili, North West Region, Cameroon.
Department of Agronomic and Applied Molecular Sciences, Faculty of Agriculture and Veterinary Medicine, University of Buea, P.O. Box 63 Buea, South West Region, Cameroon.
Heliyon. 2024 Jul 18;10(15):e34855. doi: 10.1016/j.heliyon.2024.e34855. eCollection 2024 Aug 15.
Farming practices used in maize crop production are thought to modify greenhouse gas (GHG) emissions from the soil particularly methane (CH), carbon dioxide (CO), and nitrous oxide (NO). The quantities of these GHG fluxes have rarely been estimated from smallholder farms in Sub-Saharan Africa. We estimated the quantities of GHG fluxes and Global Warming Potential (GWP) from the Push-Pull Technology (PPT) and Tillage with the Formation of Ridges (TFR) farming systems at the University of Bamenda, Cameroon. Greenhouse gases were sampled bi-monthly from April to Early August 2020 using the static chamber technique. The experiment followed a split-plot randomized complete block design with two replicates and three planting distances (1 m, 1.5 m, and 2 m) used as treatments. Mean cumulative CH (5.39 kgCH-Cha) and NO (1.03 kgNO-Nha) emissions under TFR were significantly higher (P < 0.05) than mean CH (3.59 kgCH-Cha) and NO (0.52 kgNO-Nha) emissions under PPT system. Mean net-GWP under PPT followed the trend 2 m (-267.61 ) < 1.5 m (-75.76 ) < 1 m (-24.95 ) while under TFR, net-GWP was ordered 1 m (0.38 ) < 1.5 m (85.29 ) < 2 m (288.41 ) with significant differences between them. Maize grain yields under PPT were in the trend 1 m (0.81 ) < 2 m (0.85 ) < 1.5 m (0.92 ) with a significant difference (P < 0.05) between 1 m and 1,5 m treatments. While under TFR, the trend was 2 m (0.56 ) < 1 m (0.77 ) < 1.5 m (0.80 ) with significant difference between 1.5 m and 2 m (P < 0.05). On average, PPT was a sink to GWP (-122.77 ) and revealed higher (P < 0.05) yields (0.86 ) than TFR (0.71 ) which was a source of GWP (124.69 ). Therefore, a PPT practice of 1.5 m planting distance is recommended in Sub-Saharan Africa to enhance food productivity while mitigating global warming by minimizing soil greenhouse gas emissions.
玉米作物生产中使用的耕作方式被认为会改变土壤温室气体（GHG）排放，尤其是甲烷（CH₄）、二氧化碳（CO₂）和氧化亚氮（N₂O）。这些温室气体通量的数量在撒哈拉以南非洲的小农户农场中很少被估算。我们在喀麦隆巴门达大学估算了推 - 拉技术（PPT）和起垄耕作（TFR）种植系统的温室气体通量数量和全球变暖潜能值（GWP）。2020年4月至8月初，使用静态箱技术每两个月对温室气体进行一次采样。该实验采用裂区随机完全区组设计，有两个重复，三种种植距离（1米、1.5米和2米）作为处理。TFR下的平均累积CH₄（5.39 kgCH₄ - C/ha）和N₂O（1.03 kgN₂O - N/ha）排放量显著高于（P < 0.05）PPT系统下的平均CH₄（3.59 kgCH₄ - C/ha）和N₂O（0.52 kgN₂O - N/ha）排放量。PPT下的平均净GWP遵循2米（-267.61 ）< 1.5米（-75.76 ）< 1米（-24.95 ）的趋势，而在TFR下，净GWP的顺序为1米（0.38 ）< 1.5米（85.29 ）< 2米（288.41 ），它们之间存在显著差异。PPT下玉米籽粒产量的趋势为1米（0.81 ）< 2米（0.85 ）< 1.5米（0.92 ），1米和1.5米处理之间存在显著差异（P < 0.05）。而在TFR下，趋势为2米（0.56 ）< 1米（0.77 ）< 1.5米（0.80 ），1.5米和2米之间存在显著差异（P < 0.05）。平均而言，PPT是GWP的汇（-122.77 ），并且产量（0.86 ）高于（P < 0.05）TFR（0.71 ），TFR是GWP的源（124.69 ）。因此，建议在撒哈拉以南非洲采用1.5米种植距离的PPT做法，以提高粮食生产力，同时通过减少土壤温室气体排放来缓解全球变暖。
