Scientific activity and results

This work analyzes the efficiency of various fertilization strategies to reduce the emission of nitrogen compounds from the cultivation systems to the environment of the Murcia region. The work includes detailed “grid” scales and their integration at the provincial level. The historical evolution of N balances in the long term is analyzed (1860-2018) as well as the N flows between the main compartments of the system. Eight fertilization strategies were established, including the incorporation of manures, the use of urease inhibitors or the elimination of urea, studying the effect at the “grid” or aggregate scale on crop yield and emissions of nitrous oxide, ammonia or nitrate. It is concluded that there is a significant margin for improvement with hardly any penalty in performance.

In this work, nitrogen flows are estimated and analyzed in the different compartments of the Spanish agri-food system at three system scales (crops, livestock and agri-food system) and two spatial scales (province and country) for 26 years (1990-2015). Nitrogen use efficiency has improved in some crop and livestock systems. However, pollution by N compounds has barely decreased. The Spanish provinces have been classified into four typologies depending on the main source of N that activates the system. A reconnection between crops and livestock has great potential to improve the efficiency of nitrogen use at a system scale, making the country more resilient to rising fertilizer and feed prices.

In this review, the singularity of cropping systems under a Mediterranean climate is analyzed in their relationship with nitrogen management. The work includes original data analyzing 1) the evolution of the agri-food system of the countries of the Mediterranean basin (1961-2013); 2) the interaction between nitrogen and water through the comparison of irrigated and dryland cereal crops in a Mediterranean aridity gradient, 3) the main determinants that facilitate the emissions of N compounds in their difference with the temperate climate, 4) the connection with the adaptation of cropping systems to climate change; 5) the particularities of the Mediterranean basins in their relationship with nitrate pollution. All these results are analyzed from the perspective of contributing to agro-environmental policies adapted to the particularities of Mediterranean agriculture.

This work presents the EuropeAgriDB v1.0 database including detailed information on nitrogen balances in European cropping systems at the country scale for 26 European countries (1960-2019). The balances have been improved by processing information from different databases such as FAOSTAT, Eurostat and also national sources. This work represents an improvement in the detail of the existing information, for example by the inclusion of forage crops, the different types of grasslands and their fertilization.

The carbon footprint of crop fertilization has been estimated in Spain and its provinces in the long term (1860-2018). To carry out this work, a detailed database has been developed with information on the management of nitrogen fertilization in 122 rainfed, irrigated and greenhouse crops for 50 provinces. The upstream and downstream emissions of the system have been estimated considering the differences between Mediterranean and temperate climates as well as the evolution of efficiency in fertilizer manufacturing.

In this work, a machine learning approach has been used to predict ammonia volatilization in Mediterranean cropping systems based on 234 experimental trial treatments. The “random forest” model had good predictive capacity. Fertilization dose was the main predictor. Unlike in the case of N2O, Mediterranean conditions do not have a particular effect on ammonia emissions. However, there is an indirect effect since Mediterranean systems, mainly rainfed ones, have fertilization doses lower than in temperate systems.

OpenToolFlux is a tool created to ease the processing of long series of data obtained through the measurement of Greenhouse Gas concentrations by using automatic chambers and analyzers. This equipment is increasingly used in agriculture and allow us to study the impact on the environment. The software transforms the raw data obtained in the field into gas fluxes, facilitating their subsequent analysis.

In this work, the input of nitrogen through irrigation water to European crops is estimated. It is concluded that this entry cannot be ignored. In some cases, the input of N through irrigation can even be equivalent to that of synthetic fertilizer.

In this work, databases of nitrogen balances in cropping systems around the world are compared for the first time on a country scale for 50 years. The different methodologies and approaches are analyzed and the main discrepancies discussed. A new database is proposed. This work represents a significant advance in the harmonization of the efforts carried out by 10 research groups from around the world.

In this work, very different scenarios are developed for Portugal, Spain and France considering the objectives of the Farm to Fork strategy, “business as usual” scenarios and agroecological configurations for the reduction of nitrate leaching, nitrous oxide and ammonia emissions. A typification of regions at the NUTS3 scale allows us to understand and compare the structure of the agri-food system of each region.

This work analyzes the potential of using insects (“mini-livestock”) for human consumption and as livestock feed to reduce greenhouse gas emissions from the Chinese agri-food system. It is concluded that an increase in its consumption in human and livestock systems will free up land that can be used for reforestation or to capture carbon, significantly reducing greenhouse gas emissions and the need to import feed.

In this work, the response of cereals to fertilization is analyzed based on long-term field experiments. It is concluded that the estimated long-term response curves are different from those obtained in short-term trials. The adoption of these curves is recommended in the development of scenarios.

In this work, the amount of phosphorus fertilizer that will be necessary to produce food in 2050 is estimated. It is considered that an important part of the added phosphorus (P) is adsorbed or precipitated in the soil and is not available to plants. The P’s legacy is also considered by the model. Various scenarios show the importance of good management that considers the particularity of the soils, the recovery of P from different systems and improving the efficiency of its use.

This opinion article discusses the importance of considering the interaction of water and nitrogen for sustainable resource management. The effect of climate change on nitrogen use efficiency has already been evident in recent decades. Scientists specialized in fertilization and climate must work in coordination to develop systems that mitigate climate change and in turn adapt to it.

Special issue in Agricultural Systems on the reconnection between crops and livestock to reduce nitrogen waste. This special issue is accepting articles that aim to: We can consider studies dealing with strategies to 1) reduce feed imports, thus relocating feed production, 2) improve local and regional optimal allocation of manure, and 3) improve NUE system efficiency through better crop and livestock spatial planning. All the contributions should include an evaluation of the contribution of any change to N waste reduction.