Significant advances in weed mapping from unmanned aerial platforms have been achieved in recent years. The detection of weed location has made possible the generation of site specific weed ...treatments to reduce the use of herbicides according to weed cover maps. However, the characterization of weed infestations should not be limited to the location of weed stands, but should also be able to distinguish the types of weeds to allow the best possible choice of herbicide treatment to be applied. A first step in this direction should be the discrimination between broad-leaved (dicotyledonous) and grass (monocotyledonous) weeds. Considering the advances in weed detection based on images acquired by unmanned aerial vehicles, and the ability of neural networks to solve hard classification problems in remote sensing, these technologies have been merged in this study with the aim of exploring their potential for broadleaf and grass weed detection in wide-row herbaceous crops such as sunflower and cotton. Overall accuracies of around 80% were obtained in both crops, with user accuracy for broad-leaved and grass weeds around 75% and 65%, respectively. These results confirm the potential of the presented combination of technologies for improving the characterization of different weed infestations, which would allow the generation of timely and adequate herbicide treatment maps according to groups of weeds.
Hedgerow orchard is an olive growing system where trees are planted at a super high-density higher than 20-fold (i.e., 1200–2500 trees ha
−1
) compared to the traditional density of olive orchards ...(usually 50 to 160 trees ha
−1
). It is dominating a great proportion of new plantations because harvesting can be fully mechanized, it is early bearing and has a relatively constant high productivity. However, there are a limited number of cultivars with sufficiently low vigour to be suitable for such plantation densities. For that reason, a set of low vigour cultivars and breeding selections has been used in a field experiment as rootstocks for reducing the vigour of “Picual”, the most frequent cultivar planted in Spain. Tree vigour was characterized by measuring crown height, projected and side areas, and volume through the analysis of photogrammetric point clouds created from images acquired with an unmanned aerial vehicle. A significant reduction of the ‘Picual’ vigour was observed in most of the rootstocks tested, with canopy volume reduced up to one half. High variability on vigour, first harvesting and their relative relationship was observed between the different rootstocks used. This indicates there might be enough genetic variability to perform breeding selection for dwarfing rootstocks on ‘Picual’ olive cultivar.
•The reliability of UAV-imagery for the selection of olive genotypes was studied.•Geometric traits of more than 1000 trees from 39 olive genotypes were assessed.•High variability was detected among ...olive genotypes with on-ground and UAV methods.•Genotype rankings obtained were very similar with both methods.•Olive breeder’s decision making may be fastened through this UAV-OBIA platform.
Airborne methodologies based on unmanned aerial vehicles (UAV) are becoming an extraordinary tool for implementing fast, accurate and affordable phenotyping strategies within plant breeding programs. The aim of this paper was to study the potential use of a previously developed UAV-OBIA platform, to fasten and support decision making for olive breeders regarding the selection of the most promising genotypes in terms of tree geometric traits. In particular, we have studied the feasibility of the system to efficiently classify and select olive genotypes according to four architectural parameters: tree height, crown diameter, projected crown area and canopy volume. These vegetative growth traits and their evolution during the first months after planting are key selection criteria in olive breeding programs. On-ground measurements and UAV estimations were recorded over two years (when trees were 15 and 27 months old, respectively) in two olive breeding trials using different training systems, namely intensive open vase and super high-density hedgerows. More than 1000 young trees belonging to 39 olive accessions, including new cross-bred genotypes and traditional cultivars, were assessed. Even though the accuracy in the UAV estimation compared to the on-ground measurements largely improved the second year, both methodologies detected in both years a high variability and significant differences among the studied genotypes, allowing for statistical comparisons among them. Genotype rankings based on the on-ground measures and UAV estimations were compared. The resulting Spearman’s rank coefficient correlations were very high, at above 0.85 in most cases, which highlights that very similar genotype classifications were achieved from either field-measured or airborne-estimated data. Thus, UAV imagery may be used to assess geometric traits and to develop rankings for the efficient screening and selection of genotypes in olive breeding programs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Ground LiDAR- and aerial photogrammetry-derived parameters presented differences.•Height 90th percentile, as a smoothed parameter, presented smaller differences.•A balance needs to be found as each ...system presents opposed pros and cons.•Terrestrial LiDAR-based systems allow smaller areas to be scanned more accurately.•UAV photogrammetry allows larger areas to be monitored with less detail.
Characterizing crop canopies is especially important in the management of woody crops. In this article, two systems were compared to characterise a 50 m long vineyard row section. One of the systems was a mobile terrestrial laser scanner based on a light detection and ranging (LiDAR) sensor (MTLS-LiDAR). The other was an uncrewed aerial vehicle (UAV) based system using digital aerial photogrammetry (UAV-DAP). The resulting 3D point clouds were assessed qualitatively and quantitatively. Canopy heights, widths and volumes were obtained in 0.1 m long sections along the studied row. All the parameters derived from the two systems presented statistically significant differences. The coefficients of determination between systems were 0.619 for canopy maximum heights above ground level (agl), 0.686 for 90th percentile (P90) heights agl, and 0.283 and 0.274 for maximum and P90 vegetated heights, respectively. Coefficients of determination between averaged maximum canopy width and P90 canopy width were 0.328 and 0.317, respectively. Coefficients of determination between cross-sectional areas determined from maximum widths, P90 widths and from the occupancy grid method were 0.423, 0.409 and 0.334, respectively. Total canopy volume for the entire row obtained from the three cross section estimation methods differed between 19 m3 and 25 m3. The reasons found were that the MTLS-LiDAR-derived point cloud captured the canopy top and side variability but could be affected by occlusions, mixed pixels and tall grass-like weeds present in the surveyed area. For its part, the UAV-DAP-derived point cloud tended to miss top and side shoots and somewhat smoothed canopy variability. As neither of the systems is optimal, a balance needs to be found according to the specific requirements of the survey. For this purpose, a list of pros and cons is presented to support the selection of one of the two systems for canopy monitoring. The MTLS-LiDAR system should be chosen when high detail is required but small areas are to be scanned. Alternatively, the UAV-DAP system should be chosen when large areas are to be monitored and when canopy detail is not so important. Further results are presented in Part 2 for a larger area and including pear and peach orchards with different training systems. Future research is to be conducted on how the compared systems affect variability detection and support variable-rate prescriptions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Parameters from ground LiDAR and UAV photogrammetry were highly correlated.•The correlations were higher when analysing larger row sections.•The values of the parameters extracted with the ground ...LiDAR were always higher.•Differences between point clouds were affected by the crop training system.•Specificities of each system make them best suited for different applications.
The measurement of geometric canopy parameters in woody crops is an important task in Precision Agriculture because of their correlation with crop condition and productivity. In recent years, several technological approaches have been developed as an alternative to manual measurements, which are time- and labour-consuming. Two of the most commonly used 3D canopy characterization technologies are mobile terrestrial laser scanning (MTLS) based on light detection and ranging (LiDAR) sensors, and digital aerial photogrammetry (DAP) using imagery from uncrewed aerial vehicles (UAVs). Although both are state-of-the-art and have been fully tested and validated, a complete comparison between their geometric canopy parameter estimations in different woody crops and training systems has not been carried out. For this reason, a set of geometric parameters (canopy height, projected area, and volume) of a vineyard, an intensive peach orchard, and an intensive pear orchard were measured using UAV-DAP and MTLS-LiDAR. A comparison between both kinds of measurements was performed, accounting for the length of the sections in which the crop hedgerows were divided to extract the geometric parameters. Measurements from the UAV and the MTLS were highly correlated (R2 from 0.82 to 0.94) when considering the data from the three crops together, and the correlations were higher when analysing longer row sections. The canopy geometric parameters estimated using the MTLS-LiDAR always had higher values than those from the UAV-DAP. The results presented in this work provide useful data for a more informed selection of technological approaches for 3D crop characterization in Precision Fruticulture and high-throughput phenotyping.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Assessing the spatial distribution of weeds within a field is a key step to the success of site-specific weed management strategies. Centaurea diluta (knapweed) is an emerging weed that is causing a ...major agronomic problem in southern and central Spain because of its large size, the difficulty of controlling it, and its high competitive ability. The main objectives of this study were to examine the spatial variability of C. diluta density in two wheat fields by multivariate geostatistical methods using unmanned aerial vehicle (UAV) imagery as secondary information and to delineate potential control zones for site-specific treatments based on occurrence probability maps of weed infestation. The primary variable was obtained by grid weed density field samplings, and the secondary variables were derived from UAV imagery acquired the same day as the weed field surveys. Kriging and cokriging with UAV-derived variables that displayed a strong correlation with weed density were used to compare C. diluta density mapping performance. The accuracy of the predictions was assessed by cross-validation. Cokriging with UAV-derived secondary variables generated more accurate weed density maps with a lower RMSE compare with kriging and cokriging with RVI, NDVI, ExR, and ExR(2) (the best methods for the prediction of knapweed density). Cokriged estimates were used to generate probability maps for risk assessment when implementing site-specific weed control by indicator kriging. This multivariate geostatistical approach enabled the delineation of winter wheat fields into two zones for different prescription treatments according to the C. diluta density and the economic threshold.
Obese women are more likely to experience pregnancy complications. The distribution of fat, and more particularly the rise in visceral fat, is well established to be more closely linked to the onset ...of cardiovascular disease and metabolic syndrome than obesity itself. We aim to examine the relationship between maternal visceral fat assessment in the first trimester and the appearance of adverse pregnancy outcomes. A prospective cohort study including 416 pregnant women was conducted. During the first trimester scan (11-13 + 6 weeks), all individuals had their visceral fat and subcutaneous thicknesses measured by ultrasonography. Blood samples were obtained, and maternal demographics and clinical information were documented. After delivery, the obstetric outcomes were evaluated. We contrasted two groups: one with healthy pregnancies and the other with adverse pregnancy outcomes (APO), defined as the development of at least one of the following complications: gestational diabetes mellitus, hypertensive disorders of pregnancy, abnormal fetal growth, preterm delivery or preterm premature rupture of membranes. Median maternal age was 33 and 34 years old for the uncomplicated and adverse pregnancy outcomes groups, respectively. We found that women with adverse pregnancy outcomes had higher VFT (median 30 vs. 26.5 mm,
= 0.001) and SFT (median 18.9 vs. 17.1 mm,
= 0.03). However, the visceral/subcutaneous fat ratio was not statistically different between groups. Finally, we performed a subanalysis for metabolic and placental vascular dysfunction complications. After performing a multivariate logistic regression analysis adjusted for maternal age, smoking, and mean arterial pressure, both the VFT (aOR 1.03,
< 0.001) and the ratio of visceral/subcutaneous fat (aOR 1.37,
= 0.04) were significantly associated with the development of adverse pregnancy outcomes; however, the associations of VFT and the VFT-to-SFT ratio were higher for the occurrence of gestational diabetes (aOR 1.07,
< 0.001; aOR 2.09,
= 0.001; respectively) and showed no relationships with placental complications. When conducting a first-trimester ultrasound assessment, sonographers may measure VFT without additional time or cost involved. Identification of pregnant women with increased VFT (>37 mm) may benefit from a close follow-up, especially for the development of gestational diabetes, independent of BMI.
Accurately mapping the spatial distribution of weeds within a field is a first step towards effective Site-specific Weed Management. The main objective of this study was to investigate if the ...multivariate geostatistical method of cokriging (COK) can be used to improve the accuracy of
Papaver rhoeas
L. infestations maps in winter wheat fields using high-resolution UAV imagery as ancillary information. The primary variable was obtained by intensive grid weed density field samplings and the secondary variables were derived from the UAV imagery taken the same day as the weed field samplings (e.g. wavebands and derivative products, such as band ratios and vegetation indexes). Univariate Ordinary Kriging (OK) and multivariate cokriging (COK) interpolation methods were used and compared for Papaver density mapping. The performances of the different methods were assessed by cross-validation. The results indicated that COK outperformed OK in the spatial interpolation of Papaver density. COK reduced the prediction errors and enhanced the accuracy of Papaver estimates maps. The best performances were obtained when COK was performed with the UAV-secondary variables that yielded the highest correlation with Papaver density and produced the strongest spatial cross-semivariograms. On average, the COK with UAV-derived ancillary variables improved the accuracy of mapping Papaver density by 11 to 21% compared with OK. The results suggest the great potential of high-resolution UAV imagery as a source of ancillary information to improve the accuracy of spatial mapping of sparsely sampled target variables using COK.
To evaluate the costeffectivenessof mirabegron in comparison to theantimuscarinic drugs tolterodine, solifenacin andfesoterodine, in the treatment of urgency, increasedmicturition frequency and ...urinary incontinence in patientswith overactive bladder (OAB).
A Markov model in Excel,with a time horizon of 5 years was developed fromthe National Health System and societal perspective.Clinical effectiveness was estimated from a clinical trial(SCORPIO) and a network meta-analysis. Unit costswere obtained from Spanish sources. The effectivenessof the treatments was measured as quality adjusted lifeyears(QALY). Deterministic and probabilistic sensitivityanalyses were performed.
For the 5-year time horizon, the incrementalcost per patient with mirabegron 50 mg versustolterodine was € 195.52 and € 157.42, from theNational Health System (NHS) and societal perspectivesrespectively, with a gain of 0.0127 QALY withmirabegron. Consequently, the cost of gaining a QALYwith mirabegron versus tolterodine was 15,432 € and12,425 € respectively. The probability that mirabegronwould be cost-effective at a willingness to pay thresholdof € 30,000 was: 70% (NHS) and 71% (society)versus tolterodine; 94% (NHS and society) versussolifenacin 5 mg; 84% (NHS) and 84.5% (society)versus solifenacin 10 mg; 96% (NHS and society)versus fesoterodine 4 mg; 98% (NHS) and 99% (society)versus fesoterodine 8 mg. The highest probability thatmirabegron would be cost-effective at a willingness topay threshold of € 20.000 and € 25.000 per QALYgained, is obtained versus fesoterodine 4 mg and 8 mgfrom both NHS and society perspectives.
The treatment of patients with OABwith mirabegron 50 mg is likely to be cost-effectivecompared to treatment with antimuscarinics.
Background: Probiotic supplements contain different strains of living microorganisms that promote the health of the host. These dietary supplements are increasingly being used by athletes to improve ...different aspects such as athletic performance, upper respiratory tract infections (URTIs), the immune system, oxidative stress, gastrointestinal (GI) problems, etc. This study aimed to identify the current evidence on the management of probiotics in endurance athletes and their relationship with sports performance. Methods: A systematic review of the last five years was carried out in PubMed, Scopus, Web of science, Sportdiscus and Embase databases. Results: Nine articles met the quality criteria. Of these, three reported direct benefits on sports performance. The remaining six articles found improvements in the reduction of oxidative stress, increased immune response and decreased incidence of URTIs. There is little scientific evidence on the direct relationship between the administration of probiotics in endurance athletes and sports performance. Conclusions: Benefits were found that probiotics could indirectly influence sports performance by improving other parameters such as the immune system, response to URTIs and decreased oxidative stress, as well as the monitoring of scheduled workouts.
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