3 research outputs found
Biochar and soil nitrous oxide emissions
The objective of this work was to evaluate the effect of biochar application on soil nitrous oxide emissions. The experiment was carried out in pots under greenhouse conditions. Four levels of ground commercial charcoal of 2 mm (biochar) were evaluated in a sandy Albaqualf (90% of sand): 0, 3, 6, and Mg ha-1. All treatments received 100 kg ha-1 of N as urea. A cubic effect of biochar levels was observed on the N 2O. Biochar doses above 5 Mg ha-1 started to mitigate the emissions in the evaluated soil. However, lower doses promote the emissions.The objective of this work was to evaluate the effect of biochar application on soil nitrous oxide emissions. The experiment was carried out in pots under greenhouse conditions. Four levels of ground commercial charcoal of 2 mm (biochar) were evaluated in a sandy Albaqualf (90% of sand): 0, 3, 6, and 9 Mg ha-1. All treatments received 100 kg ha-1 of N as urea. A cubic effect of biochar levels was observed on the N2O emissions. Biochar doses above 5 Mg ha-1 started to mitigate the emissions in the evaluated soil. However, lower doses promote the emissions
Recommended from our members
Evidence confirms an anthropic origin of Amazonian Dark Earths.
Arising from: Silva et al. Nature Communications https://doi.org/10.1038/s41467-020-20184-2 (2021
Integrated analysis of opportunities and trade-offs for mixed crop-livestock farm types in Amhara, Ethiopia
CONTEXT: In Ethiopia, many agricultural interventions have been introduced for mixed farm types in different biophysical and socioeconomic conditions. The contribution of such interventions to multi-objectives at farm level and beyond remains unclear. OBJECTIVE: To derive insights into interaction of multi-objectives on economic profit-, nutrition security-, and environmental performance that are relevant for improvement of farm household living income in Amhara, Ethiopia. METHODS: FarmDESIGN model evaluated performance of four stylized medium- and small-scale farm types in a low (Lay Gayint)- and high (South Achefer)- potential district: LG-M, LG-S, SA-M and SA-S. Pareto-based multi-objective optimization was performed to maximize farm profit, livestock density, dietary energy and vitamin A yield, and minimize GHG and soil N losses. Further analysis resulted in 3–4 clusters per farm type with varied farm configurations. RESULTS AND CONCLUSIONS: Higher dietary energy- and vitamin A- yield that meets household and Ethiopian society requirements increased synergistically with profit in three of the four farm type clusters, while LG-S clusters could only increase vitamin A yield substantially with profit. Only LG-M clusters intensified livestock by addition of 4–8 crossbred cows and 1–10 chickens, supported by imported feed and off-farm grazing but face strong environmental trade-offs of increased GHG and soil N losses. Chicken production (eggs and chicken meat) is an option to reduce environmental impact, increase profit and contribute to both human nutrition requirements. In LG-S, SA-M and SA-S farm type clusters, profit was generated mainly from sale of eucalyptus, maize, potato, carrot, finger millet, garlic, beetroot and banana, with eucalyptus accounting at least 35% of the crop profit. Livestock diversification in these clusters also contributed to farm revenue, but always to a smaller extent, due to relatively high management costs. A living income from farming activities was only achieved on SA-M3 as 3.96 USD/capita/day (+0.36 above the threshold). This cluster had a 2.90 ha land area, farm income almost equally generated from crop and livestock production, and successfully met all set objectives except maximizing livestock density. SIGNIFICANCE: Our study infers the need to increase land area, expand poultry and rear crossbred cows, and cultivate high value crops to realize a living income solely from agricultural activities. For implementation, current land-use policies should support farm area expansion. The suggested agricultural options, which already align with current Ethiopian development plans, must utilize sustainable measures that will not lead to short- or long-term challenges as higher GHG and soil nutrient mining