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1.
Sci Total Environ ; 694: 133718, 2019 Dec 01.
Article in English | MEDLINE | ID: mdl-31398640

ABSTRACT

Soil is a key component of the terroir concept for wine production. Indeed, the soil provides water and nutrients to the vine plants depending on its properties and environmental conditions. A part of the complexity in the production of high-quality wines is the adaptation of the winegrowing practices to soil conditions variability in space and time. Then, a deep understanding of the environmental conditions that modulate soil-plant system functioning and control the production of quality wine is crucial for future global change adaptation. This study aimed to identify environmental factors controlling red wine quality by merging both winemaker and scientist knowledge. This work was performed on a vineyard in Saint-Emilion Grand Cru appellation, France. First, we conducted field investigations for micro-terroir scale soil mapping in 2017, based on pedological prospections (pits and auger borings) and both water table levels and main meteorological parameters monitoring (from November 2017 to November 2018). Additionally, we collected for each vineyard plot the corresponding wine quality rank established each year since 2012 and based on wine tasting sessions supervised by the winemakers. Subsequently we investigated both nutrients and water availability for the vine. This was achieved through correlative analysis using soil description, roots observation and water table level, stratified according to both soil functional units and wine quality ranks maps. Results show that the water table dynamic and the soil texture have a major impact on the root pattern of vines. Our study suggests that explanatory factors for wine quality are interactions between soil-water and roots during vine crop season. Here, best soils for fine wines could be observed for both non-severe water deficit and no-limited nutrient conditions.


Subject(s)
Climate , Environment , Wine/analysis , Farms , France , Soil
2.
Sci Total Environ ; 625: 647-656, 2018 Jun 01.
Article in English | MEDLINE | ID: mdl-29304503

ABSTRACT

Soil salinization is a major threat to agricultural lands. Among salt-affected lands, coastal areas could be considered as highly complex systems, where salinization degradation due to anthropogenic pressure and climate-induced changes could significantly alter system functioning. For such complex systems, conceptual models can be used as evaluation tools in a preliminary step to identify the main evolutionary processes responsible for soil and water salinization. This study aimed to propose a conceptual model for water fluxes in a coastal area affected by salinity, which can help to identify the relationships between agricultural landscape evolution and actual salinity. First, we conducted field investigations from 2012 to 2016, mainly based on both soil (EC1/5) and water (ECw) electrical conductivity survey. This allowed us to characterize spatial structures for EC1/5 and ECw and to identify the river as a preponderant factor in land salinization. Subsequently, we proposed and used a conceptual model for water fluxes and conducted a time analysis (1962-2012) for three of its main constitutive elements, namely climate, river, and land systems. When integrated within the conceptual model framework, it appeared that the evolution of all constitutive elements since 1962 was responsible for the disruption of system equilibrium, favoring overall salt accumulation in the soil root zone.

3.
Can J Anaesth ; 64(3): 280-289, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28050801

ABSTRACT

BACKGROUND: Although intravenous dexamethasone prolongs the analgesic duration of interscalene brachial plexus block, it is uncertain whether this effect can be observed using lower doses of dexamethasone. This study evaluated the impact of intravenous dexamethasone (4 mg and 10 mg) on the analgesic duration of single-shot interscalene block after arthroscopic shoulder surgery. We hypothesized that both doses would prolong the analgesic duration compared with placebo. METHODS: This was a prospective double-blind randomized placebo-controlled study in patients undergoing elective arthroscopic shoulder surgery under regional anesthesia with a single-shot interscalene block (0.5% ropivacaine 20 mL). Patients received dexamethasone 4 mg (D4), dexamethasone 10 mg (D10), or a placebo (normal saline [NS]) intravenously at the time of block completion. The primary outcome was the duration of analgesia, defined as the time from the onset of sensory blockade to the first analgesic request. The primary outcome was first analyzed with a Kruskal-Wallis test and then with a Mann-Whitney test for pairwise between-group comparison. RESULTS: Sixty-nine patients completed the study. The median [interquartile range] duration of analgesia was significantly different between the three groups (D4, 19.7 [16.9-23.3] hr; D10, 19.1 [11.5-22.8] hr; and NS, 11.8 [9.3-14.0] hr; P = 0.001). This difference was statistically significant for D4 and D10 compared with placebo (median difference [MD], 7.8 hr; 95% confidence interval [CI], 4.6 to 11.1 hr; P < 0.001; and MD, 7.4 hr; 95% CI, 4.2 to 10.5 hr; P = 0.001, respectively) but not for D4 compared with D10 (MD, 0.5 hr; 95% CI, -2.8 to 3.7 hr; P = 0.38). CONCLUSIONS: Low doses of intravenous dexamethasone (4 mg and 10 mg) significantly prolong the analgesic duration of interscalene block. This trial was registered at ClinicalTrials.gov (NCT02412657).


Subject(s)
Arthroscopy , Dexamethasone/administration & dosage , Nerve Block , Pain, Postoperative/prevention & control , Shoulder/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Double-Blind Method , Female , Humans , Injections, Intravenous , Male , Middle Aged , Prospective Studies , Time Factors
4.
Environ Sci Pollut Res Int ; 22(10): 7676-95, 2015 May.
Article in English | MEDLINE | ID: mdl-25843822

ABSTRACT

High fertilizer input is necessary to sustain high yields in oil palm agroecosystems, but it may endanger neighboring aquatic ecosystems when excess nutrients are transported to waterways. In this study, the hydrochemical dynamics of groundwater and streams under baseflow conditions were evaluated with bi-monthly measurements for 1 year on 16 watersheds. Hydrochemical measurements were related to the spatial distribution of soil and fertilization practices across a landscape of 100 km(2), dominated by oil palm cultivation, in Central Sumatra, Indonesia. The low nutrient concentrations recorded in streams throughout the landscape indicated that the mature oil palm plantations in this study did not contribute to eutrophication of aquatic ecosystems. This was ascribed to high nutrient uptake by oil palm, a rational fertilizer program, and dilution of nutrient concentrations due to heavy rainfall in the study area. Soil type controlled dissolved inorganic N and total P fluxes, with greater losses of N and P from loamy-sand uplands than loamy lowlands. Organic fertilization helped to reduce nutrient fluxes compared to mineral fertilizers. However, when K inputs exceeded the oil palm requirement threshold, high K export occurred during periods when groundwater had a short residence time. For higher nutrient use efficiency in the long term, the field-scale fertilizer management should be complemented with a landscape-scale strategy of fertilizer applications that accounts for soil variability.


Subject(s)
Arecaceae/growth & development , Groundwater/analysis , Water Quality/standards , Ecosystem , Fertilizers/analysis , Indonesia , Soil/chemistry
5.
Sensors (Basel) ; 11(5): 4656-73, 2011.
Article in English | MEDLINE | ID: mdl-22163868

ABSTRACT

An innovative soft water level sensor is proposed to characterize the hydrological behaviour of agricultural catchments by measuring rainfall and stream flows. This sensor works as a capacitor coupled with a capacitance to frequency converter and measures water level at an adjustable time step acquisition. It was designed to be handy, minimally invasive and optimized in terms of energy consumption and low-cost fabrication so as to multiply its use on several catchments under natural conditions. It was used as a stage recorder to measure water level dynamics in a channel during a runoff event and as a rain gauge to measure rainfall amount and intensity. Based on the Manning equation, a method allowed estimation of water discharge with a given uncertainty and hence runoff volume at an event or annual scale. The sensor was tested under controlled conditions in the laboratory and under real conditions in the field. Comparisons of the sensor to reference devices (tipping bucket rain gauge, hydrostatic pressure transmitter limnimeter, Venturi channels…) showed accurate results: rainfall intensities and dynamic responses were accurately reproduced and discharges were estimated with an uncertainty usually acceptable in hydrology. Hence, it was used to monitor eleven small agricultural catchments located in the Mediterranean region. Both catchment reactivity and water budget have been calculated. Dynamic response of the catchments has been studied at the event scale through the rising time determination and at the annual scale by calculating the frequency of occurrence of runoff events. It provided significant insight into catchment hydrological behaviour which could be useful for agricultural management perspectives involving pollutant transport, flooding event and global water balance.


Subject(s)
Agriculture , Environmental Monitoring/instrumentation , Water Movements , Electric Capacitance
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