AN OVERVIEW OF FACTORS THAT INFLUENCE THE DEVELOPMENT OF CANADIAN PEATLANDS

1994 ◽  
Vol 126 (S169) ◽  
pp. 7-20 ◽  
Author(s):  
Dale H. Vitt
Keyword(s):  
Surface Water ◽  
Base Cation ◽  
Water Levels ◽  
Chemical Components ◽  
Surface Water Chemistry ◽  
Nutrient Contents ◽  
Peatland Development ◽  
The One ◽  
Peat Formation ◽  
Primary Division

AbstractCanadian peatlands can be classified into ombrotrophic bogs and minerotrophic fens, the latter subdivided into poor, moderate-rich, and extreme-rich fens, each with distinctive indicator species, acidity, alkalinity, and base cation content. If hydrology is considered the most important factor in peatland classification then the primary division must be between ombrotrophic bogs and minerotrophic fens; however both chemical and vegetational differences strongly indicate that the primary division of peatlands should be between acidic, Sphagnum-dominated bogs and poor fens on the one hand, and alkaline, brown-moss-dominated rich fens on the other. Although some metals such as sulphur and aluminum also vary along this gradient, nutrient contents of the surface waters do not. Bogs and fens are oligotrophic to mesotrophic wetlands that should be distinguished from eutrophic, non-peat-forming wetlands such as marshes and swamps by the presence in the former of a well-developed ground layer of bryophytes associated with relatively little seasonal water level fluctuation. Oligotrophy is probably maintained in bogs and poor fens by reduced water flow, whereas rich fens maintain mesotrophy by having larger water through-puts; however this is not well documented. Sphagnum appears to have real ecological significance, both in the initial stages of acidification and in controlling surface water temperature. Seasonal variation in surface water chemistry in all peatland types is relatively small, however precipitation events leading to changes in water levels do affect some chemical components. Although both autogenic and allogenic factors affect peatland development, initiation of peat formation and early development of peatlands during the Early and Mid Holocene were considerably influenced by regional climatic change. Later developmental patterns during the late Holocene and those seen at the present time appear to be more influenced by autogenic factors.

scholarly journals Modelling the recovery of surface water chemistry and the ecological implications in the British uplands

2003 ◽  
Vol 7 (4) ◽  
pp. 456-466 ◽  
Author(s):  
R. C. Helliwell ◽  
A. Jenkins ◽  
R. C. Ferrier ◽  
B. J. Cosby
Keyword(s):  
Surface Water ◽  
Base Cation ◽  
Surface Water Chemistry ◽  
Close Match ◽  
Acid Neutralising Capacity ◽  
Magic Model ◽  
Ecological Implications ◽  
Chemical Conditions ◽  
The Uk ◽  
Gothenburg Protocol

Abstract. Abstract: The MAGIC (Model of Acidification of Groundwaters in Catchments) model has been calibrated to three acid sensitive regions in the UK: Galloway, the South Pennines and Wales. These calibrations use the best available data for surface water, soil and deposition, from several UK data bases and regional sampling programmes. The model is capable of reproducing observed base cation and acid anion concentrations as reflected by a close match between observed and simulated acid neutralising capacity (ANC). Predictions to 2016 under currently agreed emission reductions, the Gothenburg Protocol, show that ANC greater than zero will be achieved at 100%, 86% and 100% of sites in Galloway, the Pennines and Wales, respectively. This indicates the potential for biological recovery and a return to ‘good status’ although chemical conditions remain some way from simulated pre-acidification conditions. In the longer term, beyond 2036 (20 years after compliance with the Gothenburg protocol), the model indicates that increased N leakage to surface waters may cause deterioration in the chemical status. Keywords: recovery, acidification, modelling, upland UK, ecology

II.—On some Recent Wells in Dorset

1908 ◽  
Vol 5 (6) ◽  
pp. 243-251
Author(s):  
W. H. Hudleston
Keyword(s):  
Water Level ◽  
Water Levels ◽  
Horizontal Distance ◽  
The One

For some years past the troops encamped at Bovington had to be content with such water as was supplied by a well a few hundred yards to the S.S.E. of the recently excavated borehole. The following particulars have been gathered respecting this well, but I cannot guarantee that in all respects they are strictly accurate. It was sunk in the Bagshot Beds about 1899, and is said to be 87 feet deep; the water-level stands at 82 feet from the surface, and the yield is 360 gallons per hour. The same Bagshot water-level was struck in the borehole. On comparing these two water-levels it is found that the one in the borehole stands at 85 feet above Ordnance Datum, whilst that in the well stands at 73 feet above O.D. This difference of 12 feet in a horizontal distance of 450 feet amounts to 1 in 37·5, showing a dip in the Bagshot Beds of 1½° to the S.S.E. This may not exactly represent the direction of maximum dip, but there are good reasons for believing that the line of maximum dip of the Bagshots hereabouts is not far from S.S.E.

scholarly journals Transient flow between aquifers and surface water: analytically derived field-scale hydraulic heads and fluxes

2012 ◽  
Vol 16 (3) ◽  
pp. 649-669 ◽  
Author(s):  
G. H. de Rooij
Keyword(s):  
Surface Water ◽  
Transient Flow ◽  
Hydrological Cycle ◽  
Realistic Model ◽  
Water Levels ◽  
Subsurface Water ◽  
Water Model ◽  
Infinite Strip ◽  
Catchment Scale ◽  
Basin Scale

Abstract. The increasing importance of catchment-scale and basin-scale models of the hydrological cycle makes it desirable to have a simple, yet physically realistic model for lateral subsurface water flow. As a first building block towards such a model, analytical solutions are presented for horizontal groundwater flow to surface waters held at prescribed water levels for aquifers with parallel and radial flow. The solutions are valid for a wide array of initial and boundary conditions and additions or withdrawals of water, and can handle discharge into as well as lateral infiltration from the surface water. Expressions for the average hydraulic head, the flux to or from the surface water, and the aquifer-scale hydraulic conductivity are developed to provide output at the scale of the modelled system rather than just point-scale values. The upscaled conductivity is time-variant. It does not depend on the magnitude of the flux but is determined by medium properties as well as the external forcings that drive the flow. For the systems studied, with lateral travel distances not exceeding 10 m, the circular aquifers respond very differently from the infinite-strip aquifers. The modelled fluxes are sensitive to the magnitude of the storage coefficient. For phreatic aquifers a value of 0.2 is argued to be representative, but considerable variations are likely. The effect of varying distributions over the day of recharge damps out rapidly; a soil water model that can provide accurate daily totals is preferable over a less accurate model hat correctly estimates the timing of recharge peaks.

scholarly journals Biomass uptake and fire as controls on groundwater solute evolution on a southeast Australian granite: aboriginal land management hypothesis

2014 ◽  
Vol 11 (15) ◽  
pp. 4099-4114 ◽  
Author(s):  
J. F. Dean ◽  
J. A. Webb ◽  
G. E. Jacobsen ◽  
R. Chisari ◽  
P. E. Dresel
Keyword(s):  
Surface Water ◽  
Plant Uptake ◽  
Plant Biomass ◽  
Chemical Species ◽  
Nutrient Elements ◽  
Surface Water Chemistry ◽  
Climatic Regions ◽  
The Past ◽  
Geochemical Mass Balance ◽  
Granite Terrain

Abstract. The chemical composition of groundwater and surface water is often considered to be dominated by water–rock interactions, particularly weathering; however, it has been increasingly realised that plant uptake can deplete groundwater and surface water of nutrient elements. Here we show, using geochemical mass balance techniques, that water–rock interactions do not control the hydrochemistry at our study site within a granite terrain in southwest Victoria, Australia. Instead the chemical species provided by rainfall are depleted by plant biomass uptake and exported, predominantly through fire. Regular landscape burning by Aboriginal land users is hypothesized to have caused the depletion of chemical species in groundwater for at least the past 20 000 yr by accelerating the export of elements that would otherwise have been stored within the local biomass. These findings are likely to be applicable to silicate terrains throughout southeast Australia, as well as similar lithological and climatic regions elsewhere in the globe, and contrast with studies of groundwater and surface water chemistry in higher rainfall areas of the Northern Hemisphere, where water–rock interactions are the dominant hydrochemical control.

scholarly journals The trend of the oxidants in boreal forest over 2007–2018: comprehensive modelling study with long-term measurements at SMEAR II, Finland

2020 ◽  
Author(s):  
Dean Chen ◽  
Putian Zhou ◽  
Tuomo Nieminen ◽  
Pontus Roldin ◽  
Ximeng Qi ◽  
...  
Keyword(s):  
Air Pollutants ◽  
Size Range ◽  
Chemical Components ◽  
Detailed Model ◽  
One Dimensional ◽  
The Past ◽  
Main Driver ◽  
The One ◽  
Long Term Trend

Abstract. Major atmospheric oxidants (OH, O3 and NO3) dominate the atmospheric oxidation capacity, while H2SO4 is considered as a main driver for new particle formation events. Although numerous studies have investigated the long-term trend of ozone in Europe, the trend of OH, NO3 and H2SO4 at specific sites are to a large extent unknown. In this study, we investigated how the trends in major atmospheric oxidants (OH, O3 and NO3) and H2SO4 changed in southern Finland during the past 12 years and discuss how these trends relate to decreasing emissions of regulated air pollutants in Europe. The one-dimensional model SOSAA has been applied in several studies at the SMEAR II station, and has been validated by measurements in several projects. Here, we ran the SOSAA model for the years 2007–2018 to simulate the atmospheric chemical components, especially the atmospheric oxidants and H2SO4 at SMEAR II. The simulations were evaluated with observations at SMEAR II for several shorter and longer campaigns. Our results show that OH increased by +1.56 (−0.8; +3.17) % yr−1 during daytime and NO3 decreased by −3.92 (−6.49; −1.79) % yr−1 during nighttime, indicating different trends of the oxidants during day and night. Sulphuric acid decreased during daytime by −5.12 (−11.39; −0.52) % yr−1, which correlated with the observed decreasing concentration of newly formed particles in the size range 3–25 nm by 1.4 % yr−1 at SMEAR II during the years 1997–2012 (Nieminen et al., 2014). Additionally we compared our simulated OH, NO3 and H2SO4 concentrations with proxies, which are commonly applied in case limited amount of parameters are measured and no detailed model simulations are available.

scholarly journals CRESCIMENTO INICIAL DO MARACUJAZEIRO AMARELO MANEJADO EM DOIS SUBSTRASTOS IRRIGADOS COM ÁGUA SALINA

Irriga ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 504-517 ◽  
Author(s):  
Lourival Ferreira Cavalcante ◽  
Geocleber Gomes de Sousa ◽  
Saulo Cabral Gondim ◽  
Fernando Luiz Figueiredo ◽  
Ícaro Herbert Lucena Cavalcante ◽  
...  
Keyword(s):  
Irrigation Water ◽  
Mass Production ◽  
Saline Water ◽  
Water Levels ◽  
Water Salinity ◽  
Initial Growth ◽  
Passiflora Edulis ◽  
Irrigation Water Salinity ◽  
The One ◽  
Shoot Mass

CRESCIMENTO INICIAL DO MARACUJAZEIRO AMARELO MANEJADO EM DOIS SUBSTRASTOS IRRIGADOS COM ÁGUA SALINA   Lourival Ferreira Cavalcante1; Geocleber Gomes de Sousa2; Saulo Cabral Gondim3; Fernando Luiz Figueiredo1; Ítalo Herbert Lucena Cavalcante4; Adriana Araujo Diniz51Departamento de Solos e Engenharia Rural, Centro de Ciências Agrárias, Universidade Federal da Paraíba, Areia, PB,  [email protected] 2Solos e Nutrição de Plantas, Centro de Ciências Agrárias, Universidade Federal Ceará, Fortaleza, CE3Recursos Naturais, Universidade Federal de Campina Grande, Campina Grande, PBUniversidade Federal do Piauí, Bom Jesus, PI5Centro de Ciências Agrárias, Universidade Federal da Paraíba, Areia, PB  1 RESUMO             O trabalho foi realizado, no período de outubro a dezembro de 2006, em ambiente protegido do CCA/UFPB – Campus II, Areia, PB, com o objetivo de avaliar os efeitos da salinidade da água de irrigação sobre o crescimento inicial do maracujazeiro amarelo (Passiflora edulis f. flavicarpa Deg) cultivado em diferentes substratos. Os tratamentos foram distribuídos em blocos casualizados com três repetições e 12 unidades experimentais por parcela, arranjados num fatorial 5 x 2, referentes aos valores de condutividade elétrica da água de irrigação ( 0,4; 1,0; 2,0; 3,0 e 4,0 dS m-1 ) e dois substratos, sendo um mais arenoso (Solo Neossolo Regolítico) e o outro mais argiloso, constituído por uma mistura do Neossolo Regolítico (50% ) mais Nitossolo Vermelho eutrófico (50%). O aumento da salinidade da água de irrigação elevou expressivamente o caráter salino dos substratos, refletindo-se na redução do crescimento pelo diâmetro caulinar, área foliar, produção de biomassa das raízes e parte aérea das plantas em ambos os casos, porém com maior intensidade no substrato constituído pela mistura de parte iguais dos solos Neossolo Regolítco e Nitossolo Vermelho. UNITERMOS: Salinidade, irrigação, Passiflora edulis, condutividade elétrica  CAVALCANTE, L. F.; SOUSA, G. G. de; GONDIM, S. C.; FIGUEIREDO, F. L.; CAVALCANTE, Í. H. L.; DINIZ, A. A. INITIAL GROWTH OF YELLOW PASSION FRUIT CROPED IN TWO SUBSTRATS MANAGED WITH SALINE WATER IN TWO SUBSTRATES  2 ABSTRACT                                    This study was carried out, during  the period of October /2006 to December /2006, in green house conditions from Agrarian Sciences Center , Federal University of Paraíba, Paraíba State, Brazil, in order to evaluate the effects of water salinity on initial growth of yellow passion plants (Passiflora edulis f. flavicarpa Deg) cultivated in different substrates. Treatments were distributed in a randomized blocks experimental design with three repetitions and 12 experimental units per parcel, in a factorial arrangement 5 x 2, referring to electrical conductivity of irrigation water levels (0.4; 1.0; 2.0; 3.0 e 4.0 dS m-1) and two substrates, being a sandy (Entisol) and a clay, composed by a mixture of Entisol (50%) and Eutrophic Red Nitosol (50%). The increasing of irrigation water salinity expressively enhanced the saline index of the substrate, reflecting in a plant growth reduction related to stem diameter, leaf area, root mass production and shoot mass production of both substrates, but more expressive for the one with equal parts of Entisol and Red Nitosol. KEYWORDS: Salinity, irrigation, Passiflora edulis, electric conductivity

scholarly journals Tailings Dust Characterization and Impacts on Surface Water Chemistry

2021 ◽  
Author(s):  
Amy Cleaver ◽  
Heather Jamieson ◽  
Carrie Rickwood ◽  
Philippa Huntsman
Keyword(s):  
Surface Water ◽  
Water Chemistry ◽  
Surface Water Chemistry
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