341 research outputs found
Wild solitary bees and their use of bee hotels in southwest Spain
There is an increasing interest in preserving and, if possible, increasing wild bee populations as evidenced by increasinginvestigations into providing supplemental nesting resources, commonly called bee hotels. The study presented herewas carried out in 2017 and 2018 with two objectives: a) to understand the role that insect refuges could have onbeneficial arthropod fauna, especially bees, and b) to evaluate different materials and which species used them. We pre-sent the preliminary results of three constructed refuges in Seville, Spain: Hymenoptera visited the refuges most fre-quently (88.7% of the visitors), of which the social wasps (Polistes dominula(Christ)) were most common, followed bybees. Bees were observed visiting bamboo canes, Arundo canes, drilled logs, and grooved boards. Drilled logs were themost used material (31.5 and 37.6% occupied in 2017 and 2018, respectively), followed by bamboo canes (14.1 and17.4% of occupied in 2017 and 2018, respectively). For drilled logs, holes of 4.9–6.5mm (2017) and 7.0–9.2 mm (2018)were preferred, whilst diameters of 2.6/2.7–4.9/5.0 mm (both 2017 and 2018) were preferred for bamboo canes. Forgrooved boards, holes of 5.0 mm (only 2018) were preferred. The bee species most frequently nesting in bamboo caneswereCeratina cucurbitina(Rossi) andCeratina dentiventrisGerstacker, whereas in drilled logsHoplitis lepeletieri(P erez)was most common, butHoplitis adunca(Panzer) was also recorded. Their abundance throughout the study period variedbetween species, and their role in biodiversity and sustaining wild flora is discussed
Identification of the water stress level in olive trees during pit hardening using the trunk growth rate indicator.
Water scarcity is generating an increasing interest in deficit irrigation scheduling. The trunk diameter fluctuations are daily cycles that have been suggested as tools for irrigation scheduling. The trunk growth rate (TGR) was suggested as the best indicator for olive trees during pit hardening. The aim of this work is to clarify how the TGR could be used to identify water stress levels. The experiment was performed during the 2017 season, in a commercial, super-high-density orchard in Carmona (Seville, Spain). Four different irrigation treatments were performed according to midday stem water potential values and TGR. The data obtained were very variable and both indicators presented a wide range of water status throughout the season. The maximum trunk diameter data clearly showed the pattern of the trees water status but the comparison between treatments and the identification of the water stress level was not possible. The average TGR was linked to the midday stem water potential, but with a minimum amount of data. Irrigation scheduling based on the average TGR was difficult because of the great increases in some daily TGR values. For clarity, the pool of data was grouped by midday stem water potential. These water stress levels were characterized using the weekly frequency of TGR values. The increase of water stress reduced the frequency of values between -0.1 and 0.3mm day-1 from 60% to less than 25%. Moderate water stress levels increased the percentage of values lower than -0.3mm day-1 from 7% to 37%. The most severe water stress conditions increased the TGR values between -0.3 and -0.1mm day-1 from 16% up to 22%.IRNASINSTITUTO DE LA GRASACSI
The COVID-19: the enzyme of the digital transformation of teaching or the reflection of a methodological and competence crisis in higher education?
[ES]La CoVId-19 ha obligado a transitar hacia una docencia y una evaluación online de urgencia y sin planificación. Realmente, no se puede decir que las universidades hayan realizado un proceso de transformación integral
de su docencia hacia el modelo online, tampoco se pretendía. Tras haber cerrado uno de los procesos que más han
impactado en la educación en general y en la Universidad en particular en tiempos, llega el momento de reflexionar y sacar
concusiones que sirvan para afrontar el futuro cercano del siguiente curso y más profundamente la evolución de la
educación superior con un horizonte temporal más amplio. En esta reflexión el optimismo llevaría pensar en un efecto
positivo de la pandemia en pro de la transformación digital integral, no solo docente, de las universidades, pero una visión
más realista destaca una profunda brecha competencial tanto en los aspectos digitales como en las metodologías docentes
que, en el caso de España, debería hacer pensar sobre la verdadera adopción real del modelo propuesto como resultado
del Espacio Europeo de Educación Superior
Spatio-temporal variability of fog-water collection in the eastern Iberian Peninsula: 2003-2012
Among the different inputs involved in the hydrological system, fog water measured by man-made passive devices is one of the most unknown components, although it could be an additional water resource for specific environmental applications (forest restoration, forest firefighting, etc.). Focusing on the Mediterranean Iberian Peninsula, the aim of this work is to quantify fog-water collected by a 24-fog-stations network spread across three latitudinal sectors with different locations (coastal, pre-littoral and inland), and to determine the most productive sites. Measurements from the network show that distance-to-sea, latitude or elevation differences between stations are factors affecting fog-water collection potential. The network, based on passive cylindrical omnidirectional fog-water collectors, was active during the period 2003-2012. In addition to fog collection, other environmental variables such as rainfall, wind speed and wind direction, air temperature and relative humidity were measured. These ancillary data were used in a specific data reduction technique to eliminate the simultaneous rainwater component from the fog water measurements, and in the retrieval of the optimum mean wind directions to harvest fog-water efficiently. It was concluded that (i) positive differences in elevation allow greater collection rates, even under 100m differences; (ii) optimum harvesting wind directions for inland locations are in line with the orientation of the existent valley coupled with the shortest path to the coastline, their collected fog-water volumes being generally smaller than those near the coast; (iii) fog-water collection at coastal locations present more dispersed optimal wind directions, ranging from north to the direction of the most immediate coastline; and (iv) there is a practically null dependence of the optimum mean wind direction on seasonality, but a strong dependence of fog-water captured volumes, however
Antioxidant capacity, fatty acids profile, and descriptive sensory analysis of table olives as affected by deficit irrigation
preprintThe influence of three irrigation treatments (T0, no stress; T1, soft stress; and, T2, moderate stress) on the key functional properties [fatty acids, sugar alcohols, organic acids, minerals, total polyphenols content (TPC), and antioxidant activity (AA)], sensory quality, and consumers' acceptance of table olives, cv. ‘Manzanilla’, was evaluated. RESULTS: A soft water stress, T1, led to table olives with the highest oil and dry matter contents, with the highest intensities of key sensory attributes and slightly, although not significant, higher values of consumer satisfaction degree. Besides, RDI in general (T1 and T2) slightly increased green colour, the content of linoleic acid, but decreased the content of phytic acid and some minerals. CONCLUSION: The soft RDI conditions are a good option for the cultivation of olive trees because they are environmentally friendly and simultaneously maintain or even improve the functionality, sensory quality, and consumer acceptance of table olives. © 2016 Society of Chemical Industry.Ministerio de Economía y Competitividad AGL2013-45922-C2-1-RMinisterio de Economía y Competitividad AGL2013-45922-C2-2-
Ares V and Future Very Large Launch Vehicles to Enable Major Astronomical Missions
The current NASA architecture intended to return humans to the lunar surface includes the Ares V cargo launch vehicle, which is planned to be available within a decade. The capabilities designed for Ares V would permit an 8.8-m diameter, 55 mT payload to be carried to Sun-Earth L1,2 locations. That is, this vehicle could launch very large optical systems to achieve major scientific goals that would otherwise be very difficult. For example, an 8-m monolith UV/visual/IR telescope appears able to be launched to a Sun-Earth L2 location. Even larger apertures that are deployed or assembled seem possible. Alternatively, multiple elements of a spatial array or two or three astronomical observatories might be launched simultaneously. Over the years, scientists and engineers have been evaluating concepts for astronomical observatories that use future large launch vehicles. In this presentation, we report on results of a recent workshop held at NASA Ames Research Center that have improved understanding of the science goals that can be achieved using Ares V. While such a vehicle uniquely enables few of the observatory concepts considered at the workshop, most have a baseline mission that can be flown on existing or near-future vehicles. However, the performance of the Ares V permits design concepts (e.g., large monolithic mirrors) that reduce complexity and risk
Influence of rootstocks on pistachio (Pistacia vera L.) water relations
Pistachio potted plants budded on three different rootstocks were submitted to water stress during 28 days with the aim of studying their water relations and physiological responses. Water stress resulted in an accented drop of stem water potential and leaf conductance. Nonetheless, pistachio plants showed a great capacity to contrast drought effects by the recourse to osmotic adjustment mechanisms. Regarding rootstocks, UCB-I results being the less adapted rootstock to conditions of water stress
Identification of water stress conditions in olive trees through frequencies of trunk growth rate
Continuous monitoring of the tree water status will enhance irrigation performance, particularly when applying
deficit schedules. The olive tree is a highly drought-resistant species and management of the water stress could
increase water savings. Trunk diameter fluctuations can be displayed as daily curves representing the shrinkage
and swelling, and can provide information about tree water status. In olive trees, trunk growth rate (TGR) is the
most useful indicator, but the daily variability reduced the commercial applications. Recently, weekly frequencies of TGR values were associated to the water status in one seasonal experiment. The aim of this work is to
study the seasonal pattern and the interannual variations of these parameters in order to integrate them in an
irrigation scheduling tool. The experiment was performed during two consecutive seasons (2018 and 2019) in a
superhigh density mature olive orchard at Carmona (Seville, Spain). Three different irrigation scheduling
treatments were considered in a randomized complete block design. The control treatment was fully irrigated
with 150–175% crop evapotranspiration (ETc) in order to ensure an optimum water status. Regulated deficit
irrigation-1 (RDI-1) was scheduled using only TGR data provided through the continuous measurements from a
dendrometer. In this treatment, water stress conditions were controlled during the pit hardening period. RDI-2
was similar to RDI-1, but with a more severe water stress conditions during pit hardening and a maximum
seasonal amount of water that limited rehydration. Water stress was greater during the 2019 season than the
2018 season, according to the midday stem water potential (SWP). Weekly frequencies of TGR values lower than
− 0.3 mm day− 1 (Severe FR) and values between − 0.1 and 0.3 mm day− 1 (Good FR) described the water status
pattern in the three treatments for both seasons. Only under severe water stress conditions (SWP more negative
than − 4 MPa) the values of these frequencies did not identify accurately the water status. However, the use of
weekly frequencies of values greater than 0.3 mm day− 1 (Alert FR) and the pattern of these Severe FR and Good
FR themselves identified such conditions. The use of these three weekly frequencies (Severe, Good and Alert
(SGA) approach) are suggested for continuous deficit irrigation scheduling in olive trees
A more sustainable and efficient definition of Regulated Deficit Irrigation phases in olive (Olea europaea L.).
Regulated deficit irrigation in table olive trees during a sensitive period
Olive tree is one of the most important irrigated fruit at Spain (around 400.000 ha). The water needs in olive orchard are greater than the water availability. Therefore, deficit conditions are common at the field. The aim of this work is to study a regulated deficit irrigation (RDI) scheduling based on midday stem water potential (Y) that limits irrigation before harvest. The experiment was performed at La Hampa experimental farm (Coria del río, Seville, Spain) in 45 years-old olive (cv Manzanillo). Three irrigation treatments in a complete randomized block design were performed during 2014.This research was supported by the Spanish Ministerio de Economía y Competitividad (MINECO), (AGL2013-45922-C2-1-R).Peer Reviewe
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