170,213 research outputs found
Results on neutrinoless double-beta decay from gerda phase i
The GERmanium Detector Array, GERDA, is designed to search for neutrinoless double-beta (0νββ) decay of 76Ge and it is installed in the Laboratori Nazionali del Gran Sasso (LNGS) of INFN, Italy. In this review, the detection principle and detector setup of GERDA are described. Also, the main physics results by GERDA Phase I, are discussed. They include the measurement of the half-life of 2νββ decay, the background decomposition of the energy spectrum and the techniques for the discrimination of the background, based on the pulse shape of the signal. In the last part of this review, the estimation of a limit on the half-life of 0νββ (T0ν1/2 >2.1 · 1025 yr at 90% C.L.) and the comparison with previous results are discussed. GERDA data from Phase I strongly disfavor the recent claim of 0νββ discovery, based on data from the Heidelberg-Moscow experiment. © 2014 World Scientific Publishing Company.The GERmaniurn Detecdor Array, GERDA, is designed to hear ch for neutrinoles doublebeta (0v beta beta) decay of Ge-76 and it is installed in the Laboratori Nazionali del Gran Sasso (LNGS) of INFN, Italy. In this review, the detection principle and detector setup of GERDA are described. Also, the maM pip sic results by GERDA Phase I, are discussed. They include the measurement of the half-life of 2v beta beta decay, the background decomposition of the energy spectrum and the techniques for the discrimination of the background, based on the pulse shape of the signal. In the last part of this review, the estimation of a limit on the half-life of 0v beta beta (T-1/2(0v) > 2.1 . 10(25) yr at 90% C.L.) and the comparison with previous results are discussed. GERDA data from Phase I strongly disfavor the recent claim of 0v beta beta discovery, based on data from the Heidelberg-Moscow experiment
Clippings return decreases mineral nitrogen requirements for bermudagrass (Cynodon spp.) lawns in Mediterranean Europe
The use of bermudagrass [Cynodon dactylon (L.) Pers.] and hybrid bermudagrass (C. dactylon x C. transvaalensis Burtt Davy) in lawns is rapidly increasing in Mediterranean Europe; however, the identification of optimal N fertilization practices is needed to shorten the long dormancy periods some cultivars undergo in these environments. A 2-yr study was conducted at the agricultural experimental farm of Padova University from May 2016 until June 2018 to compare the effects of three N fertilization rates (160 kg N ha−1 without clippings returned, 80 kg N ha−1 with clippings returned, and 80 kg N ha−1 without clippings returned applied with a controlled-release fertilizer) on two bermudagrass cultivars (‘La Paloma’, ‘Yukon’) and two hybrid bermudagrass cultivars (‘Patriot’, ‘Tifway’) by measuring summer and fall quality, spring green-up, and root morphology. Bermudagrasses fertilized at 160 kg N ha−1 without clippings returned slightly increased turfgrass quality in the summer, but higher turf quality was recorded in plots fertilized at 80 kg N ha−1 with clippings returned after weekly mowing events in the fall. The same N rates had a positive effect on spring green-up for ‘La Paloma’ and ‘Tifway’; however, no benefits of increased N rates were detected on root morphology. Results suggest that returning clippings can be a powerful tool for reducing mineral N applications and increase growing season length in northern Italy
Preliminary investigations of the Bryophyte Flora in the Hazel Groves of the Aveto Regional Natural Park (Ligurian Apennines)
This study investigates the bryological diversity of six hazel groves in the Val d’Aveto Regional Natural Park. The sampling sites were selected between the municipality of San Colombano Certenoli and Mezzanego and they represent both managed and abandoned cultivations.
The study of bryophyte diversity is part of a broader floristic characterization of the hazel groves in Aveto Park, aimed at further enhancing these crops, which are already recognized with a cultural and agri-food value. To conduct the investigations, 99 mosses were sampled
in three different substrates (soil, rock and bark)
Traffic Tolerance of Perennial Ryegrass (Lolium perenne L.) Cultivars as Affected by Nitrogen Fertilization
Perennial ryegrass (Lolium perenne L.) is one of the most widely used species for sports fields in temperate climates because of its high wear tolerance. However, wear tolerance of cultivars may vary according to local environmental conditions and turfgrass management. In this study, we evaluated the wear tolerance of six perennial ryegrass cultivars (Adagio, Apple SGL, Equate, Firebird, Principal 2, Tetradark) under two fertility treatments (100 or 200 kg N.ha21.yr21) over 2 years. The field trial was performed at the Experimental Agricultural Farm at the University of Padova in northeastern Italy in a silty loam soil. Plots were arranged in a randomized complete block with three replications and subjected to three traffic events per week using a sports field wear simulator. Turfgrass quality (TQ), percent green cover (PGC), and normalized difference vegetation index (NDVI) were recorded every 2 weeks and averaged over each month. Although perennial ryegrass cultivars responded differently to wear stress, the higher nitrogen (N) rate positively affected the TQ of them all. ‘Tetradrak’ and ‘Equate’ had the lowest TQ, especially during the active growing seasons (spring and autumn). However, ‘Tetradark’ was particularly negatively affected during the cool fall months. The impact of a higher N fertilization rate on PGC and NDVI appeared to be more pronounced in spring than in fall. Furthermore, slight differences among cultivars and treatments were observed in summer and winter when temperatures were a limiting growth factor
Multilevel modelling unveils environmental drivers of the effect of forest succession on plant species loss in Alpine pastures
Response of twenty tall fescue (schedonorus arundinaceus (schreb.) dumort.) cultivars to low mowing height
Tall fescue (Schedonorus arundinaceus (Schreb.) Dumort.) is the most widely used species in the European transition zone, however, despite its good wear tolerance, its use is still limited to lawns and landscape areas due to concerns about its ability to withstand low mowing regimes. A two years field study was conducted to access performance of twenty tall fescue cultivars (‘Ares’, ‘Armani’, ‘Dynamites LS’, ‘Firecracker SLS’, ‘Firewall’, ‘Foxhound’ ‘Granditte’, ‘JT-LT20, ‘JT-3380, ‘Karakum’, ‘Lexington’, ‘Olympic Gold’, ‘Rebounder’, ‘Rhambler SRP’, ‘Starlett’, ‘Supersonic’, ‘Talladega’, ‘Thunderstruck’, ‘Titanium 2LS’, ‘Turfway’) mowed weekly at 18 mm. Turfgrass was evaluated every two weeks for visual quality, color, density, texture and uniformity, as well as percent green cover (PGC) and dark green color index (DGCI), and normalized difference vegetation index (NDVI), and traction twice per year. Although no cultivars showed sufficient quality throughout the year, ‘Turfway’, ‘Titanium 2LS’ and ‘JT-338' achieved high quality rating during spring and fall, the two seasons with the highest frequency of games played on sports field in northern Italy. Traction ratings collected in these study fell within acceptable range for football fields. Our results suggest that improved dwarf-type tall fescue cultivars can be used in sport fields in Northern Italy
Drought resistance and recovery of kentucky bluegrass (Poa pratensis l.) cultivars under different nitrogen fertilisation rates
Kentucky bluegrass (Poa pratensis L.) is one of the most popular cool-season turfgrass species. However, little is known about the effects of N supply on its resistance to drought stress. The objective of this study was to assess the effects of acute drought followed by a recovery period on four Kentucky bluegrass cultivars (‘Barduke’, ‘Brooklawn’, ‘NuBlue Plus’ and ‘Marauder’) and one tall fescue (‘Rhambler SRP’) under two different nitrogen fertilisation rates (100 or 200 kg N ha−1 yr−1 ). The study was conducted over two years in a rain-out structure to control water input in spring and summer. The cultivars were subjected to a drought stress phase (absence of irrigation) followed by a recovery phase (weekly irrigation with an intake of 80% of ET). The green cover percentage, visual quality, NDVI, and soil moisture were measured weekly. We found that Kentucky bluegrass maintains sufficient turf quality for 2 weeks without irrigation. During the first year of the experiment, slight differences were observed among the Kentucky bluegrass cultivars, with ‘Marauder’ showing a 15% of green turf cover less than ‘Brooklawn’ after 6 weeks of acute drought, while in the second year, ‘NuBlue Plus’ displayed higher green turf cover and NDVI than the other cultivars. Nitrogen treatment had limited influence on the performances of the cultivars, ‘Marauder’ being the only one benefitting from the higher rate of applications
Hemiparasitic plants for suppressing tall fescue in golf roughs: preliminary results of using Rhinanthus alectorolophus
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