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Agriculture is the second-highest, after energy use, source of greenhouse gas emissions, which are released from soils and animal digestion processes and as a result of energy consumption at various stages of agricultural production. However, changes in the management of agricultural systems may mitigate the negative impact of this sector on the atmosphere and climate. This paper presents a literature review on energy consumption in agriculture and the potential of agricultural crop production to assist in mitigation of global warming by increasing absorption of CO2 from the atmosphere. The issue was considered in the context of managing the cultivation of main, catch and cover crops. The potential of carbon sequestration in the above- and below-ground biomass of selected crops was analyzed. It was stated that, depending on the species, main crops can sequester up to 113 CO2 ha−1 yr−1 in whole biomass, while catch or cover crops can sequester up to 14.80 CO2 ha−1 yr−1 and 0.17 CO2 ha−1 yr−1 in the above- and below-ground biomass, respectively. The benefits of the spread of catch or cover crops, such as improvement of soil quality (leading to an increase in primary crop yield by even as much as 65%) and a phytosanitary effect, as well as the barriers that limit the use of catch crops, including the problems with matching crop species to climate and soil conditions and the risk of reducing farmers' income, were considered. The results of the review show that catch crops can assimilate an additional amount of 4 to 6 tonnes CO2 ha−1 yr−1, and thus, spreading of catch crops is an effective way to reduce the climate impact of agriculture. [ABSTRACT FROM AUTHOR]

The increase in the concentration of greenhouse gases in the Earth's atmosphere, especially that of CO2, is a major concern because it is the main source leading to global warming, and its impact on climate change is still widely studied. The intensity and frequency of drought and flooding increase due to the change in climate, which has a negative impact on crop productivity and food security. The aim of this paper was to demonstrate the role of corn in carbon sequestration based on plant biomass and soil organic carbon accumulation. We presented the main factors that contribute to carbon sequestration and concrete examples regarding the capacity of corn hybrids created at National Agricultural Research and Development Institute (NARDI) Fundulea, as well as aspects regarding the importance of soil tillage and fertilisation. In contrast to genotypes in which this ratio was lower, maize genotypes that demonstrated a rise in the root:stem ratio under drought stress conditions produced more biomass, suggesting that the roots of these genotypes can grow at water potentials where stem growth is inhibited, which are attributes that also prove their good potential for carbon sequestration under climate change conditions. The organic carbon content in the superficial soil layer decreased with the intensification of the degree of soil mobilisation (9.95% when working the soil with the chisel, 17.91% for ploughing), but fertilisation had a beneficial effect. The biomass was higher than that of the unfertilised soil. This means that a higher carbon input has a positive influence on the carbon stock in the soil. [ABSTRACT FROM AUTHOR]

Conversion to no-till (NT) is usually associated to increased soil organic carbon (SOC) stocks in comparison to inversion tillage (IT). However, an important and unexplained variability in the changes in SOC with NT adoption exists, which impedes accurate prediction of its potential for C sequestration. We performed a meta-analysis with pedo-climatic and crop factors observed to influence SOC storage under NT at local and regional scales, in order to determine those better explaining this variability at a global scale. We studied SOC stocks (0-30 cm) in an equivalent soil mass, climatic and soil characteristics in 92 NT-IT paired cases. A sub-base with the 35 pairs providing C inputs was used to test their effect. Greater SOC stocks were observed with NT, with a smaller difference than often described (6.7%, i.e. 3.4 Mg C ha). Crop C inputs differences was the only factor significantly and positively related to SOC stock differences between NT and IT, explaining 30% of their variability. The variability in SOC storage induced by NT conversion seems largely related to the variability of the crop production response. Changes at the agro-ecosystem level, not only in soil, should be considered when assessing the potential of NT for C sequestration. [ABSTRACT FROM AUTHOR]