Search results for "Drought"
showing 10 items of 132 documents
Physiological and reproductive differences between hermaphrodites and males in the androdioecious plant Fraxinus ornus
2004
8 páginas, 4 figuras, 1 tabla.
The Role of Aquatic Refuge Habitats for Fish, and Threats in the Context of Climate Change and Human Impact, during Seasonal Hydrological Drought in …
2021
In spite of the obvious climate changes effects on the Carpathian Basin hydrographic nets fish fauna, studies on their potential refuge habitats in drought periods are scarce. Multiannual (2016–2021) research of fish in some streams located in the Saxon Villages area during hydrological drought periods identified, mapped, and revealed the refuge aquatic habitats presence, management needs, and importance for fish diversity and abundance for small rivers. The impact of increasing global temperature and other human activities induced hydrologic net and habitats alteration, decreased the refuge habitats needed by freshwater fish, diminished the fish abundance, and influenced the spatial and te…
Correlations between productivity elements in Lolium perenne L. species for new varieties resistant to drought
2010
Perennial ryegrass is considered the most important perennial gramineous plant due to the many possibilities of use (grass and fodder) [6, 9, 15].With the increasing emphasis put on increasing the area of green space, obtaining new biological forms - varieties of the main species of gramineous plants for turf, with increased resistance to drought and land during the summer, may represent an important objective of the research companies producing such seed [6, 7].In the present study, are given researches on correlations between productivity elements, obtained in an experiment that simulates conditions of severe drought soil, to different genotypes of the species Lolium perenne L., which is …
Morpho-physiologic traits in two sage taxa grown under different irrigation regime
2017
Sage is an important aromatic crop, extensively cultivated worldwide. Drought stress affects yield and composition of secondary metabolites such as fatty acids, essential oils, antioxidants, changing the essential oil composition profile with respect to the ISO 9909 standard. Drought tolerance may differ among genotypes, so we compared the response of Salvia officinalis L. and S. officinalis cv. ‘Maxima’ grown under two different irrigation regimes to highlight differences in leaf growth, water potential, gas exchange and essential oil composition. Potted plants were grown in the greenhouse at 100% or 50% of field water capacity for three months. Monthly measurements of 3rd node leaf length…
The Use of Non-Conventional Water Resources as a Means of Adaptation to Drought and Climate Change in Semi-Arid Regions: South-Eastern Spain
2019
Drought is a climatic risk with notable repercussions on water supply systems. The aim of this study is to analyze the principal measures for management and planning implemented during recent decades in south-eastern Spain (Segura River Basin) to respond to drought situations, focusing on the role played by non-conventional water resources (desalination and treated water). The results demonstrate that the study area (despite being one of the driest places of Spain) is less vulnerable to drought than regions with an Atlantic climate and greater availability of water. This has been possible thanks to the integration of non-conventional water resources as a means of adaptation to confront this…
Diurnal Cycle Relationships between Passive Fluorescence, PRI and NPQ of Vegetation in a Controlled Stress Experiment
2017
In order to estimate vegetation photosynthesis from remote sensing observations; some critical parameters need to be quantified. From all absorbed light; the plant needs to release any excess that is not used for photosynthesis; by non-photochemical quenching; by fluorescence emission and unregulated thermal dissipation. Non-photochemical quenching (NPQ) processes are controlled photoprotective mechanisms which; once activated; strongly control the dynamics of photochemical efficiency. With illumination conditions increasing and decreasing during a diurnal cycle; photoprotection mechanisms needs to change accordingly. The goal of this work is to quantify dynamic NPQ; measured from active fl…
Physiological and Structural Responses to Prolonged Water Deficit in Young Trees of Two Olive Cultivars
2022
This study aimed to characterize the physiological and structural responses of potted one-year-old olive trees belonging to two olive cultivars—‘Nocellara del Belice’ and ‘Cerasuola’—exposed to prolonged drought under greenhouse conditions. Two irrigation treatments based on evapotranspiration (ET) were imposed for 69 days, i.e., well-watered (WW, 100% ET) and drought-stressed (DS, 10–30% ET). Leaf stomatal conductance (gs), stem water potential (Ψstem), transpiration (E), photosynthetic capacity (Amax), water use efficiency (WUE), stem (Kstem) and root (Kroot) hydraulic conductance, trunk diameter variations (TDV), and leaf patch attenuated pre…
Climate Resilience Pathways of Rural Households. Evidence from Ethiopia
2018
This paper explores the resilience capacity of rural Ethiopian households after the drought shock occurred in 2011. The work develops an original empirical framework able to capture the policy and socio-economic determinants of households’ resilience capacity by making parametric statistical assumption on the resilience distribution. To this end, the analysis employs a two-wave representative panel dataset aligned with detailed weather records while controlling for a large set of household- and community-level characteristics. The analysis shows that the majority of these factors affects significantly resilience capacity only in the group of households affected by the drought shock, suggest…
Prevalence of dry eye disease in elderly individuals of the French population (the MONTRACHET Study)
2013
Purpose To report the prevalence of dry eye in a large population-based sample of French individuals older than 75 years. Methods About 9000 individuals 65 years and older were included in the 3C cohort study since 1999 in 3 French cities (Bordeaux, Dijon and Montpellier). In Dijon, an additional ophthalmic examination was performed 10 years after the initial inclusions to assess the relation between systemic age-related diseases and eye diseases in the MONTRACHET Study (Maculopathy Optic Nerve nuTRition neurovAsCular and HEarT diseases). Dry eye symptoms were collected with self reported history of dry eye symptoms, use of topical medications and evaluated by the Ocular Surface Disease Ind…
Drought Stress Study on Nicotiana tabacum L., “Baladi”, an In Vitro Experimental Model
2021
Crops drought tolerance is a trait of outmost importance for agriculture especially today when climate change is affecting more the production for food and feed. The scope of this article is to evaluate in vitro drought stress response of Nicotiana tabacum L., “Baladi”. The experiment was set up for four successive stages starting with in vitro seedling development, hypocotyl cultivation, three generations of micropropagation, pre-acclimatization and acclimatization. The effect of abscisic acid (ABA) and/or polyethylene-glycol 6000 (PEG) on tobacco hypocotyl caulogenesis and micropropagation were investigated. Superoxide-dismutases (SODs) and peroxidases (POXs) are more active and different…