Strategies for greenhouse gas emissions mitigation in Mediterranean agriculture: A review

[EN] An integrated assessment of the potential of different management practices for mitigating specific components of the total GHG budget (N2O and CH4 emissions and C sequestration) of Mediterranean agrosystems was performed in this study. Their suitability regarding both yield and environmental (e.g. nitrate leaching and ammonia volatilization) sustainability, and regional barriers and opportunities for their implementation were also considered. Based on its results best strategies to abate GHG emissions in Mediterranean agro-systems were proposed. Adjusting N fertilization to crop needs in both irrigated and rain-fed systems could reduce N2O emissions up to 50% compared with a non-adjusted practice. Substitution of N synthetic fertilizers by solid manure can be also implemented in those systems, and may abate N2O emissions by about 20% under Mediterranean conditions, with additional indirect benefits associated to energy savings and positive effects in crop yields. The use of urease and nitrification inhibitors enhances N use efficiency of the cropping systems and may mitigate N2O emissions up to 80% and 50%, respectively. The type of irrigation may also have a great mitigation potential in the Mediterranean region. Drip-irrigated systems have on average 80% lower N2O emissions than sprinkler systems and drip-irrigation combined with optimized fertilization showed a reduction in direct N2O emissions up to 50%. Methane fluxes have a relatively small contribution to the total GHG budget of Mediterranean crops, which can mostly be controlled by careful management of the water table and organic inputs in paddies. Reduced soil tillage, improved management of crop residues and agro-industry by-products, and cover cropping in orchards, are the most suitable interventions to enhance organic C stocks in Mediterranean agricultural soils. The adoption of the proposed agricultural practices will require farmers training. The global analysis of life cycle emissions associated to irrigation type (drip, sprinkle and furrow) and N fertilization rate (100 and 300 kg N ha(-1) yr(-1)) revealed that these factors may outweigh the reduction in GHG emissions beyond the plot scale. The analysis of the impact of some structural changes on top-down mitigation of GHG emissions revealed that 3-15% of N2O emissions could be suppressed by avoiding food waste at the end-consumer level. A 40% reduction in meat and dairy consumption could reduce GHG emissions by 20-30%. Reintroducing the Mediterranean diet (i.e. similar to 35% intake of animal protein) would therefore result in a significant decrease of GHG emissions from agricultural production systems under Mediterranean conditions. (C) 2016 Elsevier B.V. All rights reserved.The authors would like to thank the Spanish National R+D+i Plan (AGL2012-37815-C05-01, AGL2012-37815-C05-04) and very specifically the workshop held in December 2016 in Butron (Bizkaia) to synthesize the most promising measures to reduce N2O emissions from Spanish agricultural soils. BC3 is sponsored by the Basque Government. M. L. Cayuela thanks Fundacion Seneca for financing the project 19281/PI/14.Sanz-Cobeña, A.; Lassaletta, L.; Aguilera, E.; Del Prado, A.; Garnier, J.; Billen, G.; Iglesias, A.... (2017). Strategies for greenhouse gas emissions mitigation in Mediterranean agriculture: A review. Agriculture Ecosystems & Environment. 238:5-24. https://doi.org/10.1016/j.agee.2016.09.038S52423

Strategies for GHG mitigation in Mediterranean cropping systems. A review

In this review we aimed to synthetize and analyze the most promising GHGs mitigation strategies for Mediterranean cropping systems. A description of most relevant measures, based on the best crop choice and management by farmers (i.e., agronomical practices), was firstly carried out. Many of these measures can be also efficient in other climatic regions, but here we provide particular results and discussion of their efficiencies for Mediterranean cropping systems. An integrated assessment of management practices on mitigating each component of the global warming potential (N2O and CH4 emissions and C sequestration) of production systems considering potential side-effects of their implementation allowed us to propose the best strategies to abate GHG emissions, while sustaining crop yields and mitigating other sources of environmental pollution (e.g. nitrate leaching and ammonia volatilization)

Erosión y desertificación.-USLE, RUSLE and WEPP models used in mining restored hillslopes

ABSTRACT One of the main problems affecting mining restoration is erosion, which limits the development of functional soils and plant communities. The eroded sediment pollutes and degrades the natural river systems. The objective of this work is to test some of the most used models: USLE (Wischmeier and Smith, 1965, 1978) and RUSLE 1.06 (Toy and Foster, 1998) and WEPP (Nearing et al., 1989), for the case of slopes derived from mining reclamation. The study area is a dump in El Moral coalmine (Utrillas), 60 km. north of Teruel city. We selected three artificial slopes, one with a topsoil substrate and two overburdencovered in order to measure the sediment production during a year. After the comparison between estimated and measured erosion rates two conclusions can be stated: a) RUSLE 1.06 gives the best estimations in most of the cases. However WEPP in its annual option and for the topsoiled slope, works better than RUSLE1.06