Olive Actual “on Year” Yield Forecast Tool Based on the Tree Canopy Geometry Using UAS Imagery

Olive has a notable importance in countries of Mediterranean basin and its profitability depends on several factors such as actual yield, production cost or product price. Actual “on year” Yield (AY) is production (kg tree-1) in “on years”, and this research attempts to relate it with geometrical parameters of the tree canopy. Regression equation to forecast AY based on manual canopy volume was determined based on data acquired from different orchard categories and cultivars during different harvesting seasons in southern Spain. Orthoimages were acquired with unmanned aerial systems (UAS) imagery calculating individual crown for relating to canopy volume and AY. Yield levels did not vary between orchard categories; however, it did between irrigated orchards (7000–17,000 kg ha-1) and rainfed ones (4000–7000 kg ha-1). After that, manual canopy volume was related with the individual crown area of trees that were calculated by orthoimages acquired with UAS imagery. Finally, AY was forecasted using both manual canopy volume and individual tree crown area as main factors for olive productivity. AY forecast only by using individual crown area made it possible to get a simple and cheap forecast tool for a wide range of olive orchards. Finally, the acquired information was introduced in a thematic map describing spatial AY variability obtained from orthoimage analysis that may be a powerful tool for farmers, insurance systems, market forecasts or to detect agronomical problems

Reduction of the operational times and crop costs by ap- plying No Till and Guide Assistance in rainfed arable crops in Southern Spain

Abstract Andalusia, located in the South of Spain, is one of its main agrarian regions. The rainfed arable crops occupy a 39 % of its total agricultural area, more than 3.5 Mha. The continuously increasing of the agricultural inputs costs (labor, fuel, herbicides, fertilizers, etc.), and the maintenance or decreasing of the yields prices, have produced a serious reduction of incomes for the Andalusian farmers. No Till (NT) in arable crops, based in the suppression of the plow, and Guide Assistance (GA) that allows a more efficient and homogeneous work, reduce fuel and inputs consumption, and consequently the agricultural costs. Also, as they reduce and optimize the number of operations, NT & GA decrease the operational time needed to cultivate the crops. However, the change of soil management system, not only could produce variation in the yield, but also increased some inputs costs, as herbicides. So the aim of this work is: 1) Study the yield variation of arable crops managed with NT and conventional tillage (CT) in rainfed conditions. 2) Study the reduction in the operational times and crop variable costs that NT & GA could bring respect CT. This work belongs to a European project, Life + Agricarbon, and it shows the results of four seasons carried out in three rainfed farms in Southern Spain. On each experimental field, 30 hectares of arable crops, with two soil management systems (CT and NT & GA) were studied. Trials in each system followed a typical crop rotation of the Andalusian countryside: winter wheat, sunflower and legume. Different parameters on mechanized operations made in each crop and management system were logged using a remotely data acquisition system. The indicators studied in each operation were: time duration; working surface; average speed; work capacity; overlap and fuel consumption. To this end, one tractor in each farm was instrumented with different technology: GPS; fuel flow sensor, implement lift sensor and a guide assistant bar. As data acquisition system a data logger was used. The stored information about the operation was transmitted via GPRS modem to a PC. Moreover, the crop production was monitored with a crop yield monitor. The variable costs of the crops were studied for each season. They were divided in the price that farmers paid for the farming operations, seeds, agrochemicals and fertilizers used each year in the farms. for legume. This decrease was related to the reduction in the fuel consumption contributed by the NT (53 %) and the overlap of the seeding, spraying and fertilization contributed by GA. In addition to this, the operational times were average decreased in a 61 %

Sulfonated poly(vinyl alcohol)/graphene oxide composite membranes for proton exchange membrane fuel cells

Different crosslinked composite membranes of Poly(vinyl Alcohol) PVA with sulfosuccinic acid SSA as crosslinking agent and graphene oxide GO were prepared and characterized as a function of the sulfonating degree and GO percentage of each component. The chemical structure of membranes was confirmed by Fourier transform infrared spectroscopy FTIR. The good dispersion of GO into the polymer matrix was verified by scanning transmission microscopy SEM. The proton conductivity of the membranes in fully hydrated state was also investigated by electrochemical impedance spectroscopy EIS. To measure the potential use of PVA membranes as electrolyte were tested in a single proton exchange membrane fuel cell PEMFC. The results reveal that the addition of graphene oxide GO improves the thermal and mechanical stability of the composite membranes. The proton conductivity of the prepared membranes strongly increases by combination of matrix's sulfonating and introduction of GO nanoparticles. Thus, the sulfonating of the polymer matrix in the 30sPVA/SSA/GO membrane increases the proton conductivity a 42% and a 67% of maximum power density respect its homologue 30PVA/SSA membrane. In addition, 30sPVA/SSA/sGO membrane shows the lowest values of proton conductivity and maximum power density, which is consistent with the obtained water uptake values and confirms the improvement of barrier property of these composite membranes