WebGIS-Based Approach to Simulate Water and Solute Fluxes in the Miyun Basin in China

Claudins are essential components of the intercellular tight junction and major determinants of paracellular solute fluxes across epithelia and endothelia. Many members of this family display a distinct charge or size specificity, whereas others render the epithelium impermeable to transport. Due to intercellular localization, claudin-mediated transport processes are passive and driven by an electrochemical gradient. In epithelial tissues, claudins exhibit a temporal–spatial expression pattern corresponding with regional and local solute transport profiles. Whereas paracellular transport mechanisms in organs such as intestine and kidney have been extensively investigated, little is known about the molecular mechanisms determining solute transport in the peritoneum, and thus the determinants of peritoneal dialysis. Given the ubiquitous expression of claudins in endothelia and epithelia, it is predictable that claudins also contribute to pore formation and determination in the peritoneum, and that they are involved in solute flux. Therefore, we review the basic characteristics of claudin family members and their function as exemplified in renal tubular transport and give an outlook to what extent claudin family members might be of importance for solute reabsorption across the peritoneal membrane.

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Impact of switching crop type on water and solute fluxes in deep vadose zone

Water Resources Research ◽

10.1002/2015wr017612 ◽

2015 ◽

Vol 51 (12) ◽

pp. 9828-9842 ◽

Cited By ~ 19

Author(s):

T. Turkeltaub ◽

D. Kurtzman ◽

E. E. Russak ◽

O. Dahan

Keyword(s):

Vadose Zone ◽

Crop Type ◽

Solute Fluxes

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Stratigraphic controls on fluid and solute fluxes across the sediment-water interface of an estuary

Limnology and Oceanography ◽

10.4319/lo.2014.59.3.0997 ◽

2014 ◽

Vol 59 (3) ◽

pp. 997-1010 ◽

Cited By ~ 28

Author(s):

Audrey H. Sawyer ◽

Olesya Lazareva ◽

Kevin D. Kroeger ◽

Kyle Crespo ◽

Clara S. Chan ◽

...

Keyword(s):

Water Interface ◽

Solute Fluxes

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Solute fluxes and sulfur cycling in forested catchments in SW Germany as influenced by experimental (NH4)2SO4 treatments

Water Air & Soil Pollution ◽

10.1007/bf01100433 ◽

1995 ◽

Vol 79 (1-4) ◽

pp. 109-130 ◽

Cited By ~ 13

Author(s):

K. H. Feger

Keyword(s):

Sulfur Cycling ◽

Forested Catchments ◽

Solute Fluxes

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Linking soil water and solutes fluxes to soil properties and vegetation types: insights from a case-study in the high tropical Andes of Ecuador

10.5194/egusphere-egu21-7934 ◽

2021 ◽

Author(s):

Sebastián Páez-Bimos ◽

Veerle Vanacker ◽

Marcos Villacis ◽

Marlon Calispa ◽

Oscar Morales ◽

...

Keyword(s):

Soil Moisture ◽

Water Conservation ◽

Water Flux ◽

Water Fluxes ◽

Vegetation Types ◽

Tropical Andes ◽

Conservation Area ◽

Solute Fluxes ◽

Doc Concentration ◽

Water Conservation Area

The high tropical Andes ecosystem, known as p&#225;ramo, provides important hydrological services to densely populated areas in the Andean region. In order to manage these services sustainably, it is crucial to understand the biotic and abiotic processes that control both water quality and fluxes. Recent research in the p&#225;ramo highlights a knowledge gap regarding the role played by soil-vegetation interactions in controlling soil-water processes and resulting water and solute fluxes.Here, we determine the hydrological and geochemical fluxes in four soil profiles in the p&#225;ramo of the Antisana&#180;s water conservation area in northern Ecuador. Water fluxes were measured biweekly with field fluxmeters in the hydrological year Apr/2019- Mar/2020 under two contrasting vegetation types: tussock-like grass (TU) and cushion-forming plants (CU). Soil solution was collected in parallel with wick samplers and suction caps for assessing the concentrations of dissolved cations, anions and organic carbon (DOC). In addition, soil moisture was measured continuously in the upper meter of the soil profile, i.e. first three horizons (A, 2A and 2BC), using water content reflectometers. The vertical water flux in the upper meter of each soil profile was simulated using the 1D HYDRUS model. We carried out a Sobol analysis to identify sensitive soil hydraulic parameters. We then derived water fluxes by inverse modeling, based on the measured soil moisture. We validated the calculated water fluxes using the fluxmeter data. Solute fluxes were estimated by combining the water fluxes and the soil solution compositions.Our preliminary results suggest that water fluxes and DOC concentration vary under different vegetation types. The fluxmeter data from the 2A horizon indicates that the cumulative water flux under TU (2.8 - 5.7 l) was larger than under CU (0.8 &#8211; 1.1 l) during the dry season (Aug-Sep and Dec-Jan). However, the opposite trend was observed in the wet season for maximum water fluxes. Moreover, the DOC concentration in the uppermost horizon was higher under CU (47.3 &#177;2.2 mg l-1) than under TU (3.1 &#177;0.2 mg l-1) vegetation during the monitoring period. We associate the water and solute responses under different vegetation types to the contrasting soil hydro-physical and chemical properties (e.g., saturated hydraulic conductivity and organic carbon content) in the uppermost soil horizon. Our study illustrates the existence of a spatial association between vegetation types, water fluxes and solute concentrations in Antisana&#180;s water conservation area. By modelling the hydrological balance of the upper meter of the soil mantle, the water and solute fluxes will be estimated for soils with different vegetation cover.&#160;

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High-frequency river chemistry unveils the inner workings of concentration-discharge relationships during flood events

10.5194/egusphere-egu21-1348 ◽

2021 ◽

Author(s):

Paul Floury ◽

Julien Bouchez ◽

Jérôme Gaillardet ◽

Arnaud Blanchouin ◽

Patrick Ansart

Keyword(s):

High Frequency ◽

Agricultural Watershed ◽

Hydrological Processes ◽

Rain Event ◽

Exact Nature ◽

Flood Events ◽

Event Stream ◽

Major Species ◽

Solute Fluxes ◽

Short Time

Shifts in water fluxes through the Critical Zone exert a major control on stream solute export, but the exact nature of this control is still obscure, especially at the scale of relatively short flood events. To address this question, here we take advantage of a new high-frequency, flood event stream concentration&#8211;discharge (C-Q) dataset. Stream dissolved concentration of major species were recorded every 40 minutes over five major flood events in 2015/2016 recorded in a French agricultural watershed using device called the "River Lab". We focus our attention on the flood recession periods to highlight how C-Q relationships are controlled by hydrological processes within the catchment rather than by the dynamics of the rain event.We show that for C-Q relationships resulting from data acquisition over multi-year time scales and including several flood events, lumping all trends together potentially result in biases in characteristic parameters (such as exponents of a power-law fit), that are strongly dictated by data from the recession periods of the most intense floods alone.In order to evaluate the role of mixing of pre-existing water and solute pools in the catchment, we apply to solute fluxes an approach previously developed in catchment hydrology linking water storage and stream flow. This approach, which considers that hydrological processes prevail over chemical interactions during the short time spans of flood events, allows us to reproduce at first order a large diversity of shapes of recession C-Q relationships.

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Impact of projected land conversion on water balance of boreal soils in western Newfoundland

Journal of Water and Climate Change ◽

10.2166/wcc.2017.016 ◽

2017 ◽

Vol 8 (4) ◽

pp. 613-626 ◽

Cited By ~ 7

Author(s):

Daniel Altdorff ◽

Lakshman Galagedara ◽

Adrian Unc

Keyword(s):

Water Balance ◽

Agricultural Land ◽

Soil Column ◽

Nutrient Loss ◽

Land Conversion ◽

Infiltration Rates ◽

Agricultural Conversion ◽

Solute Fluxes ◽

Climate Analysis ◽

Boreal Soils

Abstract Conversion of boreal forest into agricultural land is likely to occur due to the shift of climatic zones and increasing food demand. However, any land conversion will affect the water balance and hence solute fluxes within the soil column and connected ecosystems. Understanding the consequences of land conversion on soil hydrology is essential to support an economically viable agriculture while minimizing its environmental footprint. Hydrological models can simulate these effects based on regionally adjusted climate scenarios. Here, we combined a local climate analysis with hydrological simulations (Hydrus-1D) of boreal soils before and after agricultural conversion. Historical climate analysis showed increasing temperatures and growing degree days while precipitation remains stable. Hydrological simulations revealed lower saturation and higher infiltration rates for unconverted soils, indicating lower runoff and increased infiltration and deep percolation. In contrast, agricultural soils have slower infiltration rates, particularly in the upper horizon. Over the long term, agricultural conversion consequently increases erosion risk and nutrient loss by runoff. This might further progressively limit groundwater recharge, affect hydrological processes and functions and future drought/flood conditions at catchment levels. Hence, conversion of boreal soils demands a primary identification of suitable areas to minimize its impacts.

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