Growth, anatomy, and gas exchange of Cenostigma pluviosum cultivated under reduced water levels in iron mining tailings

2021 ◽  
Author(s):  
Alessander Lopes Caetano ◽  
Maxwell Pereira de Pádua ◽  
Marcelo Polo ◽  
Moacir Pasqual ◽  
Fabricio José Pereira
Keyword(s):  
Gas Exchange ◽  
Water Levels ◽  
Mining Tailings ◽  
Iron Mining ◽  
Reduced Water

scholarly journals Gas exchange and water use efficiency in seedlings of tree species from caatinga under water levels and potassium

2021 ◽  
Vol 1 (53) ◽  
pp. 218
Author(s):  
Ediglécia Pereira Almeida ◽  
Antonio Lucineudo Oliveira Freire ◽  
Ivonete Alves Bakke ◽  
Cheila Deisy Ferreira
Keyword(s):  
Gas Exchange ◽  
Water Use Efficiency ◽  
Water Use ◽  
Tree Species ◽  
Water Levels ◽  
Use Efficiency

Effects of topsoil removal on greenhouse gas exchange of fen paludicultures

2021 ◽  
Author(s):  
Philipp-Fernando Köwitsch ◽  
Bärbel Tiemeyer
Keyword(s):  
Gas Exchange ◽  
Greenhouse Gas ◽  
Ghg Emissions ◽  
Typha Latifolia ◽  
Phosphorus Release ◽  
Water Levels ◽  
Conventional Agriculture ◽  
Topsoil Removal ◽  
Productive Land ◽  
The One

<p>Drainage is necessary for conventional agriculture on peatlands, but this practice causes high emissions of the greenhouse gases (GHG) carbon dioxide and nitrous oxide. Paludiculture is an option to mitigate these adverse environmental effects while maintaining productive land use. Whereas the GHG exchange of paludiculture on rewetted bog peat, i.e. <em>Sphagnum</em> farming, is relatively well examined, data on GHG emissions from fen paludicultures is still very scarce. As typical fen paludiculture species are all aerenchymous plants, the release of methane is of particular interest when optimising the GHG balance of such systems. Topsoil removal is, on the one hand, an option to reduce methane emissions as well as phosphorus release upon rewetting, but on the other hand, nutrient-rich topsoils might foster biomass growth.</p><p>In this project, <em>Typha angustifolia</em>, <em>Typha latifolia</em>, and <em>Phragmites australis</em> are grown at a fen peatland formerly used as grassland. Water levels will be kept at the surface or slightly above it. In parts of the newly created polder, the topsoil will be removed. To be able to separate the effects of topsoil removal and water level, four smaller sub-polders will be installed. Greenhouse gas exchange will be measured with closed manual chambers for all three species with and without topsoil removal as well as at a reference grassland site close by.</p>

Predation on tadpoles by hatchlings of the freshwater turtle

1999 ◽  
Vol 20 (2) ◽  
pp. 173-183 ◽  
Author(s):  
Mark-Oliver Rödel
Keyword(s):  
At Risk ◽  
Water Column ◽  
Body Shape ◽  
Water Levels ◽  
Freshwater Turtle ◽  
Natural Conditions ◽  
Small Prey ◽  
Regional Influence ◽  
Reduced Water

AbstractExperiments with Pelomedusa subrufa, a widespread African freshwater turtle, showed that this species consumed large quantities of tadpoles. Tadpoles preyed upon, comprised between 0.05 and 21.55% of the turtle's biomass. This demonstrated that Pelomedusa subrufa was neither gape limited nor did it ignore very small prey. Tadpoles with an ovoid body shape (Hemisus marmoratus, Hyperolius nitidulus, Ptychadena maccarthyensis), which shared, under natural conditions, the pond bottom microhabitat with the turtles, were more threatened than the robust tall-finned Kassina tadpoles that lived in the middle of the water column. The translucent, slow swimming Phrynomantis microps tadpole occurred in larger ponds and preferred the upper water column in deeper parts of the pond. This species was especially at risk in ponds with reduced water levels. Turtles, in contrast to fish or dragonfly larvae, are capable of migrating to other ponds. They therefore might have a profound regional influence on tadpole communities in ephemeral savanna ponds.

Limnological succession in reservoirs: a paleolimnological comparison of two methods of reservoir formation

1999 ◽  
Vol 56 (6) ◽  
pp. 1109-1121 ◽  
Author(s):  
Roland I Hall ◽  
Peter R Leavitt ◽  
Aruna S Dixit ◽  
Roberto Quinlan ◽  
John P Smol
Keyword(s):  
Water Level ◽  
Sediment Cores ◽  
Hydrological Regime ◽  
Community Change ◽  
Water Levels ◽  
Water Level Fluctuations ◽  
Lake Diefenbaker ◽  
Fossil Records ◽  
Variable Versus ◽  
Reduced Water

Analysis of diatoms, algal pigments, and chironomids in sediment cores from two otherwise similar prairie reservoirs demonstrated that differences in reservoir formation (river valley impoundment versus lake inundation) and hydrological regime (variable versus stable water level) resulted in distinct patterns of aquatic community change. Lake Diefenbaker, a 500-km2 reservoir created by damming the South Saskatchewan River in 1968, experiences water level fluctuations of 6 m·year-1. In contrast, impoundment of Buffalo Pound Lake in 1952 flooded a natural lake, raised mean water levels ~2.0 m, and reduced water level fluctuations from ~3 to <1 m·year-1. Comparison of fossil records showed that reservoir formation did not inevitably lead to eutrophication. Lake Diefenbaker exhibited typical reservoir ontogeny with three trophic periods, including an initial ~4-year period of eutrophy, a decade of mesotrophy, and a gradual shift to modern productive conditions. Planktonic taxa dominated diatom communities at all times, whereas benthic chironomid and algal remains were rare. In contrast, pigment analyses suggested that phytoplankton standing crops declined after impoundment in Buffalo Pound Lake but that chironomid and macrophyte populations expanded. Such site specificity in trophic development appears to result from differences in the extent of inundation (500 versus ~5 km2) and the magnitude of subsequent water level fluctuations (6.3 versus <1 m).

Use of iron mining tailings from dams for carbon nanotubes synthesis in fluidized bed for 17α-ethinylestradiol removal

2020 ◽  
Vol 260 ◽  
pp. 114099 ◽  
Author(s):  
Rayane Cristian Ferreira Silva ◽  
José Domingos Ardisson ◽  
Alexandre Alberto Chaves Cotta ◽  
Maria Helena Araujo ◽  
Ana Paula de Carvalho Teixeira
Keyword(s):  
Carbon Nanotubes ◽  
Fluidized Bed ◽  
Mining Tailings ◽  
Iron Mining

scholarly journals Seed Hydration Using the Drum Priming System

HortScience ◽  
1997 ◽  
Vol 32 (7) ◽  
pp. 1220-1221 ◽  
Author(s):  
Jabe E. Warren ◽  
Mark A. Bennett
Keyword(s):  
Zea Mays ◽  
Moisture Content ◽  
Sweet Corn ◽  
Water Levels ◽  
Distilled Water ◽  
Time Required ◽  
Conventional Systems ◽  
Reduced Water

Drum priming enhances seed performance without the waste and additional materials associated with conventional osmotic or matric priming techniques. Sweet corn (Zea mays L.) se (`White D' Lite') and sh2 (`WSS-4948') endosperm seeds were hydrated using drum priming at 25 °C for 6 hours. During each cycle, 125-g seed samples were exposed to 1.6, 3.2, 4.8, or 6.0 mL of distilled water and then rotated in a drum for 1 hour to ensure uniform uptake. At the end of this period, samples of 100 seeds (each) were removed and moisture content was determined. Drum priming hydrated all seedlots gradually, with increasing time required at reduced water levels for individual seedlots to achieve the desired moisture content (25% to 30%). Drum priming may provide a better alternative to conventional systems of priming.

scholarly journals Algal Boom Characteristics of Yeongsan River Based on Weir and Estuary Dam Operating Conditions Using EFDC-NIER Model

Water ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2295
Author(s):  
Darae Kim ◽  
Changmin Shin
Keyword(s):  
Water Level ◽  
Algal Blooms ◽  
Water Security ◽  
Water Levels ◽  
Operating Conditions ◽  
The Yellow Sea ◽  
Management Level ◽  
Average Water ◽  
Reduced Water ◽  
Regional Water

A number of hydraulic structures have been installed along the Yeongsan River, including an estuary dam and two weirs (Seungchon and Juksan). While these structures aid in regional water security and use and reduce flooding, they reduce water flow in the summer, thereby frequently causing algal blooms. This study simulated algal bloom and water quality characteristics of sections of the Yeongsan River in South Korea under different weir and estuary dam operating conditions using the Environmental Fluid Dynamics Code—National Institute of Environment Research (EFDC-NIER) model. Results showed that when the management levels of the Juksan Weir and estuary dam were maintained, simulated water levels were EL. 3.7 m in the weir section and EL. −1.2 m (below average water level of the Yellow Sea) in the dam section. When both the weir and dam were open, the water levels varied with the tide; in contrast, when the Juksan Weir alone was open, the water level was between EL. −1.2 and −0.9 m, in line with the management level of the estuary dam. Opening the weir alone reduced algal blooms by 72–84% in the weir region, and opening the estuary dam alone reduced the algal blooms by 83% in the dam region. This improvement was attributed to the reduced water retention time and dilution due to seawater inflows.

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