Decreased Water Use in a Super-Intensive Olive Orchard Mediates Arthropod Populations and Pest Damage

In Spain, water use in agriculture is expected to become limited by resources in the future. It is pertinent to study the effect of decreased irrigation on the presence of pests, plant damage, and arthropod communities in a super-intensive olive orchard examined from 2017 to 2019. Arthropods were studied with visual and vacuum sampling methods in two irrigation treatments (T1—control and T2—Regulated Deficit Irrigation (RDI)). Univariate analyses showed that the total arthropod abundance was significantly greater in T1 than in T2 in 2018 and 2019, mostly due to Diptera Nematocera. Visual sampling revealed that the feeding damage produced by Eriophyidae (Trombidiformes) was significantly lower in T2 in 2018 and 2019: 10–40% of shoots were affected in the late season compared with 50–60% affected for T1. The feeding symptoms caused by Palpita unionalis Hübner (Lepidoptera: Crambidae) and Zelleria oleastrella (Milliere) (Lepidoptera: Yponomeutidae) were significantly less for T2 than for T1. Multivariate principal response curves showed significant differences between irrigation strategies in the 2018 and 2019 data for both sampling methods. In conclusion, irrigation schemes with restricted water use (T2—RDI) help to reduce the abundance of several types of pests in olive crops, especially of those that feed on the plants’ new sprouts.

Habitat management of organic vineyard in Northern Italy: the role of cover plants management on arthropod functional biodiversity

The effect of cover plants on arthropod functional biodiversity was investigated in a vineyard in Northern Italy, through a 3-year field experiment. The following six ground cover plants were tested: Sweet Alyssum; Phacelia; Buckwheat; Faba Bean; Vetch and Oat; control. Arthropods were sampled using different techniques, including collection of leaves, vacuum sampling and sweeping net. Ground cover plant management significantly affected arthropod fauna, including beneficial groups providing ecosystem services like biological control against pests. Many beneficial groups were attracted by ground cover treatments in comparison with control, showing an aggregative numerical response in the plots managed with some of the selected plant species. Alyssum, Buckwheat and ‘Vetch and Oat’ mixture showed attractiveness on some Hymenoptera parasitoid families, which represented 72.3% of the insects collected by sweeping net and 45.7 by vacuum sampling. Phytoseiidae mites showed a significant increase on leaves of the vineyard plots managed with ground covers, in comparison with control, although they did not show any difference among the treatments. In general, the tested ground cover treatments did not increase dangerous Homoptera populations in comparison with control, with the exception of Alyssum. The potential of ground cover plant management in Italian vineyards is discussed: the overall lack of potential negative effects of the plants tested, combined with an aggregative numerical response for many beneficials, seems to show a potential for their use in Northern Italy vineyards.

Evaluation of a Vacuum Technique to Estimate Abundance of Waste Barley

Reliable estimates of seasonal waste-grain abundance are needed for wildlife conservation and management because these resources influence carrying capacity, behavior, and movement of birds. We tested efficacy and precision of a vacuum-sampling device for collecting waste barley Hordeum vulgare at Manitoulin Island, Ontario, Canada, 2011 and 2012. We used a Stihl BG 65E blower-vac to sample barley following methodology developed to sample moist-soil seeds. We collected samples by vacuum sampling (n = 51) and hand-picking (n = 51) in three randomly selected cut barley fields to estimate the proportion collected by vacuum sampling. We also collected experimental samples (n = 72) to estimate percent recovery using predetermined densities of dyed barley. Because our results were more variable and our percent recovery was less than published values, we acquired the blower-vac unit (BG 85) used in the moist-soil seed study to test for an equipment effect by repeating our experiments in 2012. We tested for equipment effects on percent recovery using generalized linear mixed-effect models with our observational and experimental data sets while controlling for spatial autocorrelation. Our analysis suggested that equipment type did not account for differences in percent recovery. Hand-picking yielded more precise estimates of waste barley density (x¯ = 97.1%, SD = 7.67%, n = 60) as compared with the blower-vacs under natural conditions (BG 65E: x¯ = 19.2%, SD = 96.0%, n = 27; BG 85: x¯ = 27.0%, SD = 40.37%, n = 24). Although the technique was not effective here for waste barley, we suggest that further research into small cereal grain applications is warranted.

Hot metal desulfurization by marble waste and fluorspar

The objective of this paper is to present an analysis of the use of residual marble mixtures in the pig iron desulfurization process. The study involved the use of: marble waste, fluorspar, lime, and hot metal. Four mixtures were made and added to a liquid hot metal - with known chemical composition - at a temperature of 1450ºC. The mass of each element was calculated from its chemical analysis and compared with an industrial mixture. All of the four mixtures used in the experiments were stirred by a mechanical stirrer. Samples were collected by vacuum sampling for times of 5, 10, 15, 20, and 30 minutes, and analysis was performed to check sulfur variation in the bath with time. The results were analyzed and they verified that it was possible to use marble waste as a desulfurizer.