Irrigation from the Sixties: Flumen-Monegros

53 Pags.- Tabls.- Maps.In arid and semiarid areas, agricultural land use is mainly restricted, in the first place, by the availability of water for crop growth. The transformation to irrigation of about 600 000 ha in the Ebro Valley has led to high increases in yield and in diversity of crops. After the Spanish Civil War (1936-39), which was followed by II World War, the Spanish food production system was heavily disrupted and food shortages appeared. This put high pressure on the development of new irrigated schemes which had been planned many years ago. In the Flumen-Monegros area, the technology available in the late fifties was based on flood-irrigation systems, with no previous soil studies, an empirical land evaluation, no control of saltinization risk and, finally, levelling without topsoil preservation. The extension of salinity and/or sodicity-affected soils in the Ebro Valley (IRYDA, 1977) was 200 000 ha, from which 160 000 were located in Aragon, mainly in Bardenas, Cinca and Flumen-Monegros area. But Alberto et al. (1984) reckron this data in 300 000 ha. As a result of these studies, ILACO (1975) designed two experimental drainage plots. Although the existence of salt-affected soils was known, information about the extent, location and general functioning at landscape level of those soils was lacking in the area. Some of the problems related to land use and soil management which are present now in the area or can be expected in the near future are:- Salinity-Sodicity: Diagnosis, monitoring and rehabilitation of salt-affected soils. - Soil structural degradation and surface crust formation. - Need for improved efficiency in water use: irrigation technology, water reuse, ... - Control of drainage-system degradation: open-air drains as well as underground drains. Several approaches at different scales have been adopted to work on these issues. Satellite images have been used to monitor land use and its temporal variability. Classical soil mapping at 1: 100000 level have been performed; in addition various detailed studies have been undertaken in model areas using the electromagnetic and four electrode sensors, micromorphological techniques, scanning electronic microscopy, and land evaluation procedures. The results have been presented in several papers: about salinity-sodicity trends in the Flumen sector (Herrero, 1987); about parameters related to water behaviour (Aragues, 1986); about soil porosity in plough horizons (Rodriguez-Ochoa, 1998); about translocation of solid materials (Rodriguez-Ochoa, et al. 1989; Porta and Rodriguez-Ochoa, 1991; Rodriguez-Ochoa, 1998); about degradation of underground drainage systems by mineral siltation (Herrero et al. 1989; Rodriguez-Ochoa, et al. 1989; Munoz, 1991; RodriguezOchoa, 1998).Other studies performed in the area include: Soil-vegetation relationships (Herrero, 1981); laboratory trials with different amendments in the drainage trench infilling material (Porta et al. 1996); dispersive processes because of soil structural instability (Amezketa and Aragues, 1990; Aragues and Amezketa, 1991; Amezketa and Aragues, 1995) and degradation of the hydraulic conductivity of soils (Amezketa and Aragues, 1989; Aragues and Amezketa, 1991; Amezketa and Aragues, 1995). The trip to the Flumen-Monegros area undertakes some of these points, and the stops are located in some of the main soil units. Discussion will be centered on aspects of soil genesis, classification and mapping, land use and soil conservation.Peer reviewe

Micromorphology of salt accumulations in soils of north Monegros, Spain: optical microscopy and SEM

4 Pags., 4 Figs., 2 Tabls.In this study, four areas affected by soil salinity were sampled in order to determine the mineralogy, morphology, formation conditions, and regional variations of the soil salt accumulations.This study was funded by the Spanish project AGL 2009-08931.Peer reviewe

Micromorphology of salt accumulations in soils os north Monegros, Spain: optical microscopy and SEM

4 Pags.- 2 Tabls.- 4 Figs.In this study, four areas affected by soil salinity were sampled in order to determine the mineralogy, morphology, formation conditions, and regional variations of the soil salt accumulations.This study was funded by the Spanish project AGL 2009-08931. We thank J. Wierzchos (CSIC-Madrd), R. Juliá (CSICBarcelona) and J. Herrero (CSIC-Zaragoza) for their support.Peer reviewe

Fertilizing Methods and Nutrient Balance at the End of Traditional Organic Agriculture in the Mediterranean Bioregion: Catalonia (Spain) in the 1860s

By reconstructing the nutrient balance of a Catalan v illage circa 1861-65 we examine the sustainability of organic agricultural sy stems in the northwest Mediterranean bioregion prior to the green rev olution and the question of whether the nutrients extracted f rom the soil were replenished. With a population density of 59 inhabitants per square km, similar to other northern European rural areas at that time, and a lower liv estock density per cropland unit, this v illage experienced a manure shortage. The gap was f illed by other labour-intensiv e way s of transf erring nutrients f rom uncultiv ated areas into the cropland. Key elements in this agricultural sy stem were v iney ards because they hav e f ew nutrient requirements, and woodland and scrublands as sources of relev ant amounts of nutrients collected in sev eral ways

Assessing the energy trap of industrial agriculture in North America and Europe: 82 balances from 1830 to 2012

Early energy analyses of agriculture revealed that behind higher labor and land productivity of industrial farming, there was a decrease in energy returns on energy (EROI) invested, in comparison to more traditional organic agricultural systems. Studies on recent trends show that efficiency gains in production and use of inputs have again somewhat improved energy returns. However, most of these agricultural energy studies have focused only on external inputs at the crop level, concealing the important role of internal biomass flows that livestock and forestry recirculate within agroecosystems. Here, we synthesize the results of 82 farm systems in North America and Europe from 1830 to 2012 that for the first time show the changing energy profiles of agroecosystems, including livestock and forestry, with a multi-EROI approach that accounts for the energy returns on external inputs, on internal biomass reuses, and on all inputs invested. With this historical circular bioeconomic approach, we found a general trend towards much lower external returns, little or no increases in internal returns, and almost no improvement in total returns. This “energy trap” was driven by shifts towards a growing dependence of crop production on fossil-fueled external inputs, much more intensive livestock production based on feed grains, less forestry, and a structural disintegration of agroecosystem components by increasingly linear industrial farm managements. We conclude that overcoming the energy trap requires nature-based solutions to reduce current dependence on fossil-fueled external industrial inputs and increase the circularity and complexity of agroecosystems to provide healthier diets with less animal products

Call to restrict neonicotinoids

On 28 April 2018 the European Parliament voted for a complete and permanent ban on all outdoor uses of the three most commonly used neonicotinoid pesticides. With the partial exception of the state of Ontario, Canada, governments elsewhere have failed to take action. Below is a letter, signed by 232 scientists from around the world, urgently calling for global action by policy makers to address this issue