scholarly journals The Effect of Human Impact on the Water Quality and Biocoenoses of the Soft Water Lake with Isoetids: Lake Jeleń, NW Poland

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 945 ◽  
Author(s):  
Piotr Klimaszyk ◽  
Dariusz Borowiak ◽  
Ryszard Piotrowicz ◽  
Joanna Rosińska ◽  
Elżbieta Szeląg-Wasielewska ◽  
...  
Keyword(s):  
Water Chemistry ◽  
Human Impact ◽  
Buffer Capacity ◽  
Fold Increase ◽  
Soft Water ◽  
Oxygen Conditions ◽  
Water Ph ◽  
Recreation Use ◽  
Recreational Use ◽  
Isoetes Lacustris

Soft water lakes with isoetids (SLI) are ecosystems prone to degradation due to the low buffer capacity of their waters. One of the main threats resulting from human impact is eutrophication due to agriculture, catchment urbanization and recreational use. In this paper, changes in the water chemistry and transformation of biocoenoses of one of the largest Polish SLI, Lake Jeleń, over the past 30 years are presented. The lake is located within the borders of a city, and a significant part of its catchment is under agriculture and recreation use. The physicochemical (concentration of nutrients, organic matter, electrical conductivity, oxygen saturation and water pH) and biological parameters (macrophytes and phytoplankton) were measured in summer 1991, 2004, 2013 and 2018. Since the beginning of the 1990s, a gradual increase in the trophy of the lake has been observed as indicated by increased nutrient availability, deterioration of oxygen conditions and a decrease in water transparency. The alterations of water chemistry induce biological transformations, in particular, an increase in phytoplankton abundance (4-fold increase of biomass in epilimnion) as well as a gradual reduction in the range of the phytolittoral (from 10 to 6 m), a decrease in the frequency of isoetids, Lobelia dortmanna and Isoetes lacustris, and expansion of plant species characteristic for eutrophy.

Acids, bases and buffer solutions

2018 ◽  
Author(s):  
Dennis Sherwood ◽  
Paul Dalby
Keyword(s):  
First Principles ◽  
Buffer Capacity ◽  
Unique Feature ◽  
Dissociation Constants ◽  
Equilibrium Composition ◽  
Buffer Solutions ◽  
Acid And Base ◽  
Water Ph ◽  
Acids And Bases ◽  
Conjugate Bases

Many reactions in solution involve acids and bases, and so this chapter examines these important reactions in detail. Topics covered include the ionisation of water, pH, pOH, acids and bases, conjugate acids and conjugate bases, acid and base dissociation constants, the Henderson-Hasselbalch equation, the Henderson-Hasselbalch approximation, buffer solutions and buffer capacity. A unique feature of this chapter is a ‘first principles’ analysis of how a reaction buffered at a particular pH achieves an equilibrium composition different from that of the same reaction taking place in an unbuffered solution. This introduces some concepts which are important in understanding the biochemical standard state, as required for Chapter 23.

Regulation of intracellular calcium in N1E-115 neuroblastoma cells: the role of Na+/Ca2+exchange

2002 ◽  
Vol 282 (5) ◽  
pp. C1000-C1008 ◽  
Author(s):  
Kara L. Kopper ◽  
Joseph S. Adorante
Keyword(s):  
Membrane Potential ◽  
Intracellular Calcium ◽  
Normal Cell ◽  
Buffer Capacity ◽  
Neuroblastoma Cells ◽  
Fold Increase ◽  
Scorpion Venom ◽  
Reverse Mode ◽  
Intracellular Ca

In fura 2-loaded N1E-115 cells, regulation of intracellular Ca2+ concentration ([Ca2+]i) following a Ca2+ load induced by 1 μM thapsigargin and 10 μM carbonylcyanide p-trifluoromethyoxyphenylhydrazone (FCCP) was Na+ dependent and inhibited by 5 mM Ni2+. In cells with normal intracellular Na+ concentration ([Na+]i), removal of bath Na+, which should result in reversal of Na+/Ca2+exchange, did not increase [Ca2+]i unless cell Ca2+ buffer capacity was reduced. When N1E-115 cells were Na+ loaded using 100 μM veratridine and 4 μg/ml scorpion venom, the rate of the reverse mode of the Na+/Ca2+ exchanger was apparently enhanced, since an ∼4- to 6-fold increase in [Ca2+]ioccurred despite normal cell Ca2+ buffering. In SBFI-loaded cells, we were able to demonstrate forward operation of the Na+/Ca2+ exchanger (net efflux of Ca2+) by observing increases (∼ 6 mM) in [Na+]i. These Ni2+ (5 mM)-inhibited increases in [Na+]i could only be observed when a continuous ionomycin-induced influx of Ca2+ occurred. The voltage-sensitive dye bis-(1,3-diethylthiobarbituric acid) trimethine oxonol was used to measure changes in membrane potential. Ionomycin (1 μM) depolarized N1E-115 cells (∼25 mV). This depolarization was Na+dependent and blocked by 5 mM Ni2+ and 250–500 μM benzamil. These data provide evidence for the presence of an electrogenic Na+/Ca2+ exchanger that is capable of regulating [Ca2+]i after release of Ca2+ from cell stores.

scholarly journals The-Proof-of-Concept of Biochar Floating Cover Influence on Water pH

Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1802 ◽  
Author(s):  
Zhanibek Meiirkhanuly ◽  
Jacek A. Koziel ◽  
Andrzej Białowiec ◽  
Chumki Banik ◽  
Robert C. Brown
Keyword(s):  
Buffer Capacity ◽  
Corn Starch ◽  
Tap Water ◽  
Spatial And Temporal Variation ◽  
Gaseous Emissions ◽  
Inorganic Contaminants ◽  
Ph Indicator ◽  
Ph Change ◽  
Air Interface ◽  
Water Ph

Studies have shown that biochar has the potential to remove organic and inorganic contaminants from wastewater. pH is known to have a crucial role in the transformation of pollutants. In this research, we explore the feasibility of using biochars properties to control the pH near the water–air interface, so the gaseous emissions from water (or wastewater) could be mitigated. This study aimed to test the effects of a thin layer biochar addition on the spatial and temporal variation of water pH. Two types of biochar and water were tested. Highly alkaline porous (HAP; pH 9.2) biochars made of corn stover and red oak (RO; pH 7.5) were applied surficially to tap (pH 9.5) and deionized water (DI) (pH 5.4). The spatial pH of solutions was measured every 1 mm of depth on days 0, 2, and 4 after biochar application. The results showed that HAP biochar increased the pH of both tap and DI water, while RO decreased tap water pH and increased DI water pH. On day 0, there was no effect on tap water pH, while a pH change in DI water was observed due to its lower buffer capacity. In addition, the pH (temporal) migration from topically applied biochar into an aqueous solution was visualized using a colorimetric pH indicator and corn starch to increase viscosity (to prevent biochars from sinking). The results prove that the surficial application of biochar to water was able to change both the pH near the water–air interface and the pH of the solution with time. The pH change was dependent on the biochar pH and water buffer capacity. These results warrant further research into the floatability of biochars and into designing biochars with specific pH, which could be a factor influencing gaseous emissions from liquids that are sensitive to pH.

Gill membrane remodeling with soft-water acclimation in zebrafish (Danio rerio)

2007 ◽  
Vol 30 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Paul M. Craig ◽  
Chris M. Wood ◽  
Grant B. McClelland
Keyword(s):  
Danio Rerio ◽  
Metal Toxicity ◽  
Model Organism ◽  
Fold Increase ◽  
Soft Water ◽  
Membrane Remodeling ◽  
Protein Levels ◽  
High Degree ◽  
Carbonic Anhydrase 1 ◽  
Mrna Expression Levels

Little is known regarding the ionoregulatory abilities of zebrafish exposed to soft water despite the popularity of this model organism for physiology and aquatic toxicology. We examined genomic and nongenomic changes to gills of zebrafish as they were progressively acclimated from moderately hard freshwater to typical soft water over 7 days and held in soft water for another 7 days. Gills were sampled daily and mRNA expression levels of gill Na+-K+-ATPase (NKA) α1a subunit, epithelium calcium channel (ECaC), carbonic anhydrase-1 and 2 (CA-1, CA-2), Na+/H+ exchanger (NHE-2), V-type proton (H+)-ATPase, and copper transport protein (CTR-1) were quantified by real-time PCR. Changes in enzyme activities of gill NKA were determined and protein levels of NKA and ECaC were quantified by Western blotting. Levels of mRNA for ECaC increased fourfold after day 6, with an associated increase in ECaC protein levels after 1 wk in soft water. CA-1 and CA-2 exhibited a 1.5- and 6-fold increase in gene expression on days 6 and 5, respectively. Likewise, there was a fivefold increase in NHE-2 expression after day 6. Surprisingly, CTR-1 mRNA showed a large transient increase (over threefold) on day 6, while H+-ATPase mRNA did not change. These data demonstrate a high degree of phenotypic plasticity in zebrafish gills exposed to an ion-poor environment. This not only enhances our understanding of ionoregulatory processes in fish but also highlights the need for proper experimental design for studies involving preacclimation to soft water (e.g., metal toxicity).

scholarly journals Nitric Oxide and Oxygen Regulate Truncated Hemoglobin Gene Expression in Frankia Strain CcI3

2008 ◽  
Vol 190 (23) ◽  
pp. 7864-7867 ◽  
Author(s):  
James Niemann ◽  
Louis S. Tisa
Keyword(s):  
Gene Expression ◽  
Nitric Oxide ◽  
Nitrosative Stress ◽  
Fold Increase ◽  
Low Oxygen ◽  
Truncated Hemoglobin ◽  
Frankia Strain ◽  
Hemoglobin Gene ◽  
Oxygen Conditions ◽  
Strain Cci3

ABSTRACT The Frankia genome contains two truncated hemoglobin genes (hboN and hboO) whose functions remain to be determined. Nitric oxide (NO) generated by the addition of 400 μM SNAP (S-nitroso-N-acetylpenicillamine) caused a 10-fold increase in hboN gene expression but had no effect on hboO expression. The addition of the NO scavenger, carboxy-PT10, reduced the effect of SNAP. hboO gene expression increased under low-oxygen conditions, while hboN expression was unaffected. These results suggest that HboN may function in protection from nitrosative stress and that HboO may act as an oxygen transport molecule for increased respiration in hypoxic environments.

Differential tolerances among soft-water macrophyte species to acidification

1990 ◽  
Vol 68 (10) ◽  
pp. 2127-2134 ◽  
Author(s):  
G. H. P. Arts ◽  
J. G. M. Roelofs ◽  
M. J. H. De Lyon
Keyword(s):  
The Netherlands ◽  
Key Words ◽  
Indicator Species ◽  
Historical Data ◽  
Sandy Soils ◽  
Soft Water ◽  
Ecological Groups ◽  
Sharp Distinction ◽  
Macrophyte Species ◽  
Water Ph

Twenty-six macrophyte species were studied for their degree of tolerance to extremely acid conditions. They are characteristic of soft water on sandy soils in The Netherlands. These species were divided into two groups based on their recent distribution by pH and alkalinity. The first group consists of the species that can (at least temporarily) survive under extremely acid conditions (pH < 5); the second group contains species that are limited by a distinct minimum pH of the water (pH 5–6). This sharp distinction between groups on.the basis of pH can be used for reconstruction of the development of acidification in waters using historical data on the macrophytes involved. The two groups of species can be used to discriminate between two types of soft water in The Netherlands. Key words: soft-water macrophytes, ecological groups of macrophytes, autecology, acidification, indicator species.

scholarly journals Evaluation of the balneability conditions of the urubuí corredeira, in the municipality of presidente figueiredo – amazonas

2020 ◽  
pp. 35566-35571
Keyword(s):  
Water Quality ◽  
High Risk ◽  
Water Resources ◽  
Direct Observation ◽  
Environmental Conservation ◽  
Recreational Activity ◽  
Primary Contact ◽  
Recreation Use ◽  
Recreational Use

According to the environmental company of the state of São Paulo, bathing is associated with the use of water for the practice of recreational activity through primary contact, being understood as direct and long contact with water, with high risk of ingesting certain. For this purpose, it is essential to evaluate water quality, following some criteria, which are based on microorganisms indicating fecal contamination, established through monitoring and confrontation with pre-established standards. Thus, the general objective of this study is to evaluate the watering conditions of the vulture rapids, to define the quality and parameters of water for recreation use, in order to contribute to the environmental conservation and supervision of water resources. This research is a case study, conducted through bibliographic surveys, site visits, direct observation. The results obtained by laboratory analysis in the periods between September and October 2019, where all dates of points P1 and P2 presented concentrations below 250 CFU / 100mL. According to CONAMA Resolution No. 274/2000, the results indicate that the bathing conditions for recreational use fall into the excellent category.

scholarly journals Activation of Cadmium Under Simulated Solar Illumination and Its Impact on the Mobility of Cd in Flooded Soils

2021 ◽  
Author(s):  
Bihao Luo ◽  
Chenfeng Xiao ◽  
Yuling Liu ◽  
Li Li ◽  
Liang Peng ◽  
...  
Keyword(s):  
Fold Increase ◽  
Environmental Water ◽  
Solar Irradiation ◽  
Natural Soil ◽  
Release Kinetic ◽  
Flooded Soils ◽  
Paramagnetic Resonance ◽  
Water Ph ◽  
The Stability ◽  
Electron Paramagnetic

Abstract In waterlogged paddy soils, cadmium (Cd) can be precipitated as cadmium sulfide (CdS) under reductive environment, thereby limiting the absorption of Cd by plants. Multiple environmental factors (such as water, pH, Eh, etc.) played a role in the control of Cd mobility and bioavailability. In this study, we investigated the influence of the solar irradiation on the photo-dissolution of synthetic CdS-montmorillonite composites (CdS-M) in solution and the stability of Cdin natural soil. The release kinetic of Cd2+ showed that after the irradiation of simulated sunlight, CdS-M composites became less stable compared to the dark control. The solar irradiation seemed to enhance the release of Cd2+ from CdS significantly and continuously. Electron paramagnetic resonance (EPR) and quenching experiments confirmed that the photogenerated holes, O2·- and •OH were possibly involved in the photo-induced release of Cd2+, while the holes was primarily responsible for the reaction.Irradiation under alkaline solution or the presence of DOM, PO43-, CO32- and urea markedly inhibited the photodissolution process of CdS. The photo-mediated activation of Cd was further confirmed in paddy soil under natural sunlight, with a nearly 3-fold increase in concentration of extractable Cd during the 15 days irradiation. This study highlights the importance of photochemical transformation of Cd in the environmental water and soil.

ACIDIFICATION AND pH BUFFERING CAPACITY OF ALLUVIAL SOILS UNDER SUGARCANE

1998 ◽  
Vol 34 (2) ◽  
pp. 231-243 ◽  
Author(s):  
A. E. HARTEMINK
Keyword(s):  
Papua New Guinea ◽  
Buffer Capacity ◽  
Buffering Capacity ◽  
Nitrogen Application ◽  
Average Decrease ◽  
Ph Buffering ◽  
Application Rates ◽  
Water Ph ◽  
Natural Grassland ◽  
Sampling Times

Changes in soil pH water (pHw) were investigated on a sugarcane plantation in the Ramu Valley of Papua New Guinea. The plantation was established in 1979 from natural grassland and the dominant soils were Fluvents and Vertisols. Statistical analysis of the topsoil pHw data (n = 541) showed a significant (α = 0.01) decrease from 6.5 to 5.7 between 1979 and 1996. Based on samples from 80 fields at different sampling times, the average decrease in topsoil pHw was calculated to be 0.4 units after 10 years of continuous sugarcane cultivation (r2 = 0.481). Between 1986 and 1996, subsoil pHw also decreased significantly (α < 0.05) by 0.4 and 0.3 units in the 0.30–0.45 and 0.45–0.60 m horizons respectively. The acidification trend accelerated in the 1990s when trash-harvesting replaced pre-harvesting burning and sulphate of ammonia became the dominant nitrogen fertilizer. Between 1991 and 1995, average nitrogen application rates were 90 ka ha−1 a−1 which resulted in an annual addition of 11.6 kmol H+ ha−1. The soil buffer capacity was estimated to be 125 kmol H+ ha−1 pH−1 which implied that the pHw could further decrease by 0.5 unit after five annual applications of 90 kg N ha−1 pH−1 as sulphate of ammonia. Although these soils were young in pedological terms and they had been cultivated for less than 20 years, they had acidified significantly and this could affect sugarcane production adversely if such trend were to continue.

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