Salt Weathering, a Neglected Geological Erosive Agent in Coastal and Arid Environments

Nature ◽  
1965 ◽  
Vol 205 (4976) ◽  
pp. 1097-1098 ◽  
Author(s):  
H. W. WELLMAN ◽  
A. T. WILSON
Keyword(s):  
Salt Weathering ◽  
Arid Environments

ACTION ON MATTER: THE HISTORY OF THE UNIQUELY AFRICAN TAMPER AND CONCAVE ANVIL POT-FORMING TECHNIQUE

2003 ◽  
Vol 1 (1) ◽  
pp. 3-35 ◽  
Author(s):  
Judy Sterner ◽  
Nicholas David
Keyword(s):  
Historical Development ◽  
Weight Ratio ◽  
High Volume ◽  
Efficient Production ◽  
Arid Environments ◽  
Historical Evidence ◽  
Culture History ◽  
History Of ◽  
And Diffusion

The publication, largely by ethnoarchaeologists, of new data on the tamper and concave anvil technique of pot-forming (TCA) permits a reassessment of this uniquely African technique, its toolkit, and its culture history. A survey, inspired by the technologie culturelle school, of its varied expressions in the southern Saharan, Sahelian and northern Sudan zones from Mali to Sudan and extending north into Egypt emphasises the potential of the technique for the efficient production of spherical water jars of high volume to weight ratio, much appreciated in arid environments. The technique is demanding and therefore practised for the most part by specialists. The origins and diffusion of the technique are assessed in the light of the ethnological, archaeological, linguistic, and historical evidence, and a four stage historical development is sketched.

Temperature-Profile Methods for Estimating Percolation Rates in Arid Environments

2003 ◽  
Vol 2 (1) ◽  
pp. 12 ◽  
Author(s):  
Jim Constantz ◽  
Scott W. Tyler ◽  
Edward Kwicklis
Keyword(s):  
Temperature Profile ◽  
Arid Environments

scholarly journals Extensive Variation in the Activities of Pseudocerastes and Eristicophis Viper Venoms Suggests Divergent Envenoming Strategies Are Used for Prey Capture

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 112
Author(s):  
Bianca op den Brouw ◽  
Francisco C. P. Coimbra ◽  
Lachlan A. Bourke ◽  
Tam Minh Huynh ◽  
Danielle H. W. Vlecken ◽  
...  
Keyword(s):  
Prey Capture ◽  
Anticoagulant Activity ◽  
Protein Composition ◽  
Coagulation Factors ◽  
Arid Environments ◽  
Factor X ◽  
Venom Protein ◽  
Research Attention ◽  
Future Assessment ◽  
Viper Venoms

Snakes of the genera Pseudocerastes and Eristicophis (Viperidae: Viperinae) are known as the desert vipers due to their association with the arid environments of the Middle East. These species have received limited research attention and little is known about their venom or ecology. In this study, a comprehensive analysis of desert viper venoms was conducted by visualising the venom proteomes via gel electrophoresis and assessing the crude venoms for their cytotoxic, haemotoxic, and neurotoxic properties. Plasmas sourced from human, toad, and chicken were used as models to assess possible prey-linked venom activity. The venoms demonstrated substantial divergence in composition and bioactivity across all experiments. Pseudocerastes urarachnoides venom activated human coagulation factors X and prothrombin and demonstrated potent procoagulant activity in human, toad, and chicken plasmas, in stark contrast to the potent neurotoxic venom of P. fieldi. The venom of E. macmahonii also induced coagulation, though this did not appear to be via the activation of factor X or prothrombin. The coagulant properties of P. fieldi and P. persicus venoms varied among plasmas, demonstrating strong anticoagulant activity in the amphibian and human plasmas but no significant effect in that of bird. This is conjectured to reflect prey-specific toxin activity, though further ecological studies are required to confirm any dietary associations. This study reinforces the notion that phylogenetic relatedness of snakes cannot readily predict venom protein composition or function. The significant venom variation between these species raises serious concerns regarding antivenom paraspecificity. Future assessment of antivenom is crucial.

scholarly journals A multiscale assessment of Red-tailed Hawk reproductive success relative to urban density and habitat type

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Justin H White ◽  
Jessi L Brown ◽  
Zachary E Ormsby
Keyword(s):  
Urban Areas ◽  
Urban Expansion ◽  
Habitat Type ◽  
Nesting Success ◽  
Arid Environments ◽  
Hatch Date ◽  
Urban Density ◽  
Landscape Characteristics ◽  
Suburban Areas ◽  
Breeding Seasons

Abstract Despite the unique threats to wildlife in urban areas, many raptors have established successfully reproducing urban populations. To identify variations in raptor breeding ecology within an urban area, we compared metrics of Red-tailed Hawk reproductive attempts to landscape characteristics in Reno and Sparks, NV, USA during the 2015 and 2016 breeding seasons. We used the Apparent Nesting Success and logistic exposure methods to measure nesting success of the Red-tailed Hawks. We used generalized linear models to relate nesting success and fledge rate to habitat type, productivity to hatch date (Julian day) and hatch date to urban density. Nesting success was 86% and 83% for the respective years. Nesting success increased in grassland-agricultural and shrub habitats and decreased in riparian habitat within the urban landscape. Productivity was 2.23 and 2.03 per nest for the breeding seasons. Fledge rates were 72% and 77%, respectively, and decreased in riparian areas. Nestlings hatched earlier with increased urban density and earliest in suburban areas, following a negative quadratic curve. Nesting success and productivity for this population were high relative to others in North America. Productivity increased in habitats where ground prey was more accessible. We suggest that suburban areas, if not frequently disturbed, provide sufficient resources to sustain Red-tailed Hawks over extended periods. As urban expansion continues in arid environments globally, we stress that researchers monitor reproductive output across the urban predator guild to elucidate patterns in population dynamics and adaptation.

scholarly journals Exogenously Used 24-Epibrassinolide Promotes Drought Tolerance in Maize Hybrids by Improving Plant and Water Productivity in an Arid Environment

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 354
Author(s):  
El-Sayed M. Desoky ◽  
Elsayed Mansour ◽  
Mohamed M. A. Ali ◽  
Mohamed A. T. Yasin ◽  
Mohamed I. E. Abdul-Hamid ◽  
...  
Keyword(s):  
Drought Tolerance ◽  
Agronomic Traits ◽  
Water Productivity ◽  
Positive Association ◽  
Net Photosynthesis ◽  
Antioxidant Enzyme Activities ◽  
Severe Drought ◽  
Arid Environments ◽  
Maize Hybrids ◽  
Semi Arid

The influence of 24-epibrassinolide (EBR24), applied to leaves at a concentration of 5 μM, on plant physio-biochemistry and its reflection on crop water productivity (CWP) and other agronomic traits of six maize hybrids was field-evaluated under semi-arid conditions. Two levels of irrigation water deficiency (IWD) (moderate and severe droughts; 6000 and 3000 m3 water ha−1, respectively) were applied versus a control (well-watering; 9000 m3 water ha−1). IWD reduced the relative water content, membrane stability index, photosynthetic efficiency, stomatal conductance, and rates of transpiration and net photosynthesis. Conversely, antioxidant enzyme activities and osmolyte contents were significantly increased as a result of the increased malondialdehyde content and electrolyte leakage compared to the control. These negative influences of IWD led to a reduction in CWP and grain yield-related traits. However, EBR24 detoxified the IWD stress effects and enhanced all the above-mentioned parameters. The evaluated hybrids varied in drought tolerance; Giza-168 was the best under moderate drought, while Fine-276 was the best under severe drought. Under IWD, certain physiological traits exhibited a highly positive association with yield and yield-contributing traits or CWP. Thus, exogenously using EBR24 for these hybrids could be an effective approach to improve plant and water productivity under reduced available water in semi-arid environments.

scholarly journals Soluble Salts Quantitative Characterization and Thermodynamic Modeling on Roman Bricks to Assess the Origin of Their Formation

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2866
Author(s):  
Claudia Scatigno ◽  
Nagore Prieto-Taboada ◽  
Giulia Festa ◽  
Juan Manuel Madariaga
Keyword(s):  
Archaeological Site ◽  
Risk Level ◽  
Salt Weathering ◽  
Soluble Salts ◽  
High Concentration ◽  
Quantitative Characterization ◽  
Chromatography Analysis ◽  
Acidic Gases ◽  
Hygroscopic Moisture ◽  
Ostia Antica

The environmental weathering and the formation of efflorescences on the brick walls are studied at the “Casa di Diana” Mithraeum at Ostia Antica archaeological site. Previous studies on subsoil, bedrock, hydrological systems and environmental conditions, and new ion chromatography analysis combined with ECOS-RUNSALT and Medusa-Hydra thermodynamic modelling software, had allowed us to identify the subsoil contamination related to soluble salts. The atmospheric acidic gases, CO2 and SO2, are determined as the main salt weathering species. A dry deposition after a subsequent hydration action from the shallow freshwater aquifer that reaches up to 1 m on the walls is identified as the mechanism of salt formation. An evaluation of potential sources such as the nearby Fiumicino airport, CO2-rich gases inputs from fumaroles and CO2 inputs was also debated. The risk level of contamination the surfaces of the materials should be considered mildly/very polluted with a medium/high risk of hygroscopic moisture due to the high concentration of sulphates.

scholarly journals Maize Seedling Establishment, Grain Yield and Crop Water Productivity Response to Seed Priming and Irrigation Management in a Mediterranean Arid Environment

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 756
Author(s):  
AbdAllah M. El-Sanatawy ◽  
Ahmed S. M. El-Kholy ◽  
Mohamed M. A. Ali ◽  
Mohamed F. Awad ◽  
Elsayed Mansour
Keyword(s):  
Grain Yield ◽  
Deficit Irrigation ◽  
Water Productivity ◽  
Irrigation Management ◽  
Seed Priming ◽  
Severe Drought ◽  
Arid Environments ◽  
Crop Water ◽  
Crop Water Productivity ◽  
Irrigation Regimes

Water shortage is a major environmental stress that destructively impacts maize production, particularly in arid regions. Therefore, improving irrigation management and increasing productivity per unit of water applied are needed, especially under the rising temperature and precipitation fluctuations induced by climate change. Laboratory and field trials were carried out in the present study, which were aimed at assessing the possibility of promoting maize germination, growth, grain yield and crop water productivity (CWP) using seed priming under different irrigation regimes. Two seed priming treatments, i.e., hydro-priming and hardening versus unprimed seeds, were applied under four irrigation regimes, i.e., 120, 100, 80 and 60% of estimated crop evapotranspiration (ETc). The obtained results indicated that increasing irrigation water from 100% up to 120% ETc did not significantly increase grain yield or contributing traits, while it decreased CWP. Deficit irrigation of 80 and 60% ETc gradually decreased grain yield and all attributed traits. Seed priming significantly ameliorated seedlings’ vigor as indicated by earlier germination, higher germination percentage, longer roots and shoots, and heavier fresh and dry weight than unprimed seeds with the superiority of hardening treatment. Additionally, under field conditions, seed priming significantly increased grain yield, yield contributing traits and CWP compared with unprimed treatment. Interestingly, the results reflect the role of seed priming, particularly hardening, in mitigating negative impacts of drought stress and enhancing maize growth, grain yield and attributed traits as well as CWP under deficit irrigation conditions. This was demonstrated by a significant increase in grain yield and CWP under moderate drought and severe drought conditions compared with unprimed treatment. These results highlight that efficient irrigation management and seed priming can increase maize yield and water productivity in arid environments.

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