The potential of conservation agriculture to mitigate climate change in mediterranean areas

Abstract

Agriculture contributes to climate change, and is affected by it. On the one hand, solar energy is used primarily by photosynthetic organisms which transform it into carbohydrates, releasing oxygen (O2) whilst consuming carbon dioxide (CO2) and water. In inland areas, agriculture and forestry favor photosynthesis which is performed by plants and trees; that is how this chemical reaction that sustains life is generated. On the other hand, several agricultural activities, for example soil tillage and fertilization of crops, favor the emission into the atmosphere of greenhouse gases (GHG), such as CO2 and nitrous oxide (N2O). Therefore, the role of agriculture is twofold: as crops and trees consume some of the CO2 in the atmosphere for photosynthetic reactions, and agricultural field tasks emit GHG. In other words, with regards to climate change, agriculture is part of the problem, but it is also part of the solution. Currently, about 9% of total GHG emissions in the European Union come from agriculture, which is considered a net emitter of greenhouse gases. However, agriculture has an asset that no other productive sector may boast: the soil. There are various scientific studies that warn of the precarious situation of soils in areas where the intensification of agriculture has led to intensive tillage as a conventional practice to prepare the seedbed. In addition, there are numerous studies which confirm how, through conservation, agriculture soil quality is considerably improved, and that a sustainable use of soils can be achieved. The term “sustainable” is used in almost all areas related to agriculture and the environment. It is a word not only appealing to non-specialists, but also for scientists and technicians in the field. The overuse of terms related to sustainability has produced misunderstandings, such as some specific benefits of particular agricultural systems being wrongly attributed to others. The scientific literature confirms that not all agricultural practices have an equal impact on the environment...

La agricultura contribuye al cambio climático y se ve afectada por él. La energía solar es utilizada en primer lugar por los organismos fotosintéticos que la transforman consumiendo dióxido de carbono (CO2) y agua, liberando oxígeno (O2) y generando hidratos de carbono. En las zonas continentales, gracias a la agricultura y la silvicultura, mediante la fotosíntesis que realizan las plantas y árboles se genera esta reacción química que sustenta la vida. Por otra parte, diversas actividades agrícolas, como el laboreo del suelo y la fertilización de los cultivos, favorecen la emisión a la atmósfera de gases de efecto invernadero como el CO2 y el óxido nitroso (N2O). Por tanto, en el sector agrario se presenta la doble vertiente de, por un lado, consumir parte del CO2 presente en la atmosfera para las reacciones fotosintéticas, y por otro lado, emitir también gases de efecto invernadero debido a las tareas propias del ámbito agrario. En otras palabras, la agricultura es parte del problema pero también parte de la solución al reto del cambio climático. Actualmente, alrededor del 9% del total de las emisiones de gases de efecto invernadero de la UE provienen de la agricultura, por lo que se considera un sector emisor neto de gases de efecto invernadero. No obstante, la agricultura tiene un activo que ningún otro sector productivo posee: el suelo. No son pocos los estudios científicos que alertan de la precaria situación de los suelos en zonas donde la intensificación de la agricultura ha conllevado el laboreo intensivo como práctica convencional. Afortunadamente, no son pocos los estudios que confirman cómo a...