Search results for "IRRIGATION"
showing 10 items of 342 documents
Modelling biogeochemical processes in sediments from the north western Adriatic Sea: response to enhanced POC fluxes
2017
Abstract. This work presents the result of a study carried out in the north-western Adriatic Sea, by combining two different types of biogeochemical models with field sampling efforts. A longline mussel farm was taken as a local source of perturbation to the natural POC downward flux. This flux was first quantified by means of a pelagic model of POC deposition coupled to sediment traps data, and its effects on sediment bioirrigation capacity and OM degradation pathways were investigated by constraining an early diagenesis model, linked to new data in sediment porewaters. The measurements were performed at stations located inside and outside the area affected by mussel farm deposition. Model…
Presence of illicit drugs in surface waters of protected natural wetlands connected to traditional irrigation systems and urban areas
2013
Ponencia presentada en el I Simposio sobre Gestión del Agua en Espacios Protegidos celebrado en La Habana (Cuba) del 2 al 6 de noviembre de 2010
A novel device for intracolonoscopy cleansing of inadequately prepared colonoscopy patients: a feasibility study.
2019
Abstract Background The importance of high quality preprocedural bowel preparation is widely acknowledged, but suboptimal bowel cleansing still occurs in up to 20 % of all colonoscopy patients. The aim of this study was to evaluate the performance of a novel intraprocedural cleaning device for cleaning poorly prepared colons. Methods This multicenter feasibility study included patients aged 18 – 75 years who were referred for colonoscopy. Intraprocedural cleaning was performed in patients after a limited preprocedural bowel preparation regimen (2 days of dietary restrictions and 2 × 10 mg bisacodyl). The primary outcome was the proportion of adequately prepared patients (Boston Bowel Prepar…
Assessing Hydrus-2D model to investigate the effects of different on-farm irrigation strategies on potato crop under subsurface drip irrigation
2019
The objective of this paper was to assess the performance of Hydrus-2D model to simulate the effects of different on-farm irrigation strategies applied on potato crop. The ability of the model to simulate the stress coefficient (Ks), obtained as the ratio between actual and maximum transpiration, and to define the productive function of potato crop under the semi-arid conditions of central Tunisia were also evaluated. Experiments were carried out on potato crop under full (FI) and deficit irrigation (DI) and two different water qualities supplied by means of a subsurface drip irrigation system. Results evidenced that the model, despite some discrepancies locally observed, can fairly accurat…
Monitoring Yield and Fruit quality parameters in Open-Canopy Tree crops under Water Stress. Implications for ASTER
2007
Work on water stress detection at tree and orchard levels using a high-spatial airborne thermal sensor is presented, showing its connection with yield and some fruit quality indicators in olive and peach commercial orchards under different irrigation regimes. Two airborne campaigns were conducted with the Airborne Hyperspectral Scanner (AHS) over olive and peach orchards located in Córdoba, southern Spain. The AHS sensor was flown at three different times on 25 July 2004 and 16 July 2005, collecting 2 m spatial resolution imagery in 80 spectral bands in the 0.43– 12.5 μm spectral range. Thermal bands were assessed for the retrieval of land surface temperature using the split-window algorith…
Latent heat flux variability and response to drought stress of black poplar: A multi-platform multi-sensor remote and proximal sensing approach to re…
2022
Abstract High-throughput mapping of latent heat flux (λET) is critical to efforts to optimize water resources management and to accelerate forest tree breeding for improved drought tolerance. Ideally, investigation of the energy response at the tree level may promote tailored irrigation strategies and, thus, maximize crop biomass productivity. However, data availability is limited and planning experimental campaigns in the field can be highly operationally complex. To this end, a multi-platform multi-sensor observational approach is herein developed to dissect the λET signature of a black poplar (Populus nigra) breeding population (“POP6”) at the canopy level. POP6 comprised more than 4600 …
Effects of partial rootzone drying and rootstock vigour on dry matter partitioning of apple trees (Malus domesticacvar Pink Lady)
2011
SUMMARYThe effects of partial rootzone drying (PRD) and rootstock vigour on dry matter accumulation and partitioning among leaves, shoots, fruits, frame and roots of apple trees (Malus domesticaBorkh. cvar Pink Lady) were investigated in 2005 near Caltavuturo, in Sicily. In a first field trial, trees on MM.106 rootstock were subjected to: conventional irrigation (CI), maintaining soil moisture above 0·80 of field capacity; PRD irrigation, where alternating sides of the rootzone received 0·50 of the CI irrigation water; and continuous deficit irrigation (DI), where 0·50 of the CI water was equally applied to both sides of the rootzone. In a second trial, trees on M.9 or MM.106 were subjected…
CO2 uptake of Opuntia ficus-indica (L.) Mill. whole trees and single cladodes, in relation to plant water status and cladode age
2013
Most of net photosynthesis determinations in Opuntia ficus-indica come from measurements on individual cladodes. However, they have limitations when used to scale up to whole canopy gas exchange, because a large variability of carbon assimilation may occur within the canopy, due to, among others, differences in cladode age and intercepted radiation or individual cladode response to abiotic stresses. The aim of this work was to evaluate the application of open gas exchange chambers, simultaneously applied around the whole canopy, to measure net CO 2 uptake, continuously over a 24 h period, in single Opuntia ficus-indica (L.) Mill. potted trees and in relation with their water status. Net CO2…
Response of vine leaf water potential to quick variation in canopy exposure. Example of canopy opening manipulation of Merlot (<em>Vitis vinife…
2004
<p style="text-align: justify;">Plants are in general subject to rapid fluctuations in the environment, particularly as regards the interception of light and therefore water regime. It is important to know the duration and the amplitude of response of the water regime (first leaf water potential) when light interception changes suddenly under natural conditions. widely planted grape variety in the world) was chosen mainly because it offers convenient possibilities of canopy manipulation, ranging from an open and exposed type architecture, to a closed and shaded configurations simply by moving inside or outside a «foldable Lyre» type trellis. Leaf water potential was measured throughou…
Comparative responses of ‘Gala’ and ‘Fuji’ apple trees to deficit irrigation: Placement versus volume effects
2012
Aims: Climate, soil water potential (SWP), leaf relative water content (RWC), stomatal conductance (gs), fruit and shoot growth, and carbohydrate levels were monitored during the 2008 and 2009 growing seasons to study the responses of 'Gala' and 'Fuji' apple trees to irrigation placement or volume. Methods: Three irrigation treatments were imposed, conventional irrigation (CI), partial root-zone drying (PRD, 50% of CI water on one side of the root-zone, which was alternated periodically), and continuous deficit irrigation (DI, 50% of CI water on both sides of the root-zone). Results: After each irrigation season, DI generated twice the soil water deficit (SWDint) than PRD (average of dry an…