Ba/Sr ratios as a tracer for soil water contribution to stream water in a small catchment in northern Sweden

Surface water samples from the Maolan National Natural Reserved Park (MNNRP) were analyzed from Sept. 2013 to June 2014, for major ion concentrations (K+, Na+, Ca2+, Mg2+, Cl−, SO42−, HCO3−), δ13C-DIC and δ34S-SO42− to quantify the sources of solutes and chemical weathering. The results show that HCO3− and SO42− are the main anions in Banzhai watershed, which account for 86.2 and 10.4% of the total anion equivalent, respectively. While Ca2+ and Mg2+ account for 76.9 and 20.5%, respectively. Considerable Mg2+ in stream water indicates that it may be affected by dolomite weathering. stream water samples present the δ13C-DIC values in the range of −16.9‰~−10.8‰ (mean value was −13.9‰), which were lower than that of the groundwater. The δ34S-SO42− values ranged from −15.2‰ to 1.7‰ (mean value was −4.4‰). There was a negative correlation between HCO3− content and δ13C value, implying the result of the interaction of temperature and precipitation intensity in different seasons. The significant positive correlation between SO42− content and δ13C-DIC indicates that H2SO4 may be involved in the weathering process of carbonate rocks in small watershed scale. The content of SO42− in a school sample site was much higher than that of other sample sites for the interference from human sources. The δ34S values show that the average δ34S-SO42− in most sites is close to the δ34S isotopic values of Guizhou coal and rain, indicating that they may be affected by local coal.

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Runoff generation processes in permafrost-influenced area of the Heihe River Headwater

10.5194/egusphere-egu21-1660 ◽

2021 ◽

Author(s):

Fan Zhang ◽

Xiong Xiao ◽

Guanxing Wang

Keyword(s):

Soil Water ◽

Stream Water ◽

Hydrological Regime ◽

Summer Rainfall ◽

Frozen Soil ◽

Heihe River ◽

The Tibetan Plateau ◽

Permafrost Degradation ◽

Runoff Generation ◽

Spring Snowmelt

Permafrost degradation under global warming may change the hydrological regime of the headwater catchments in alpine area such as the Tibetan Plateau (TP). In this study, he runoff generation processes in permafrost-influenced area of the Heihe River Headwater were investigated with the following results: 1) The observed stable isotope values of various water types on average was roughly in the order of snowfall and snowmelt < bulk soil water (BSW) < rainfall , stream water, mobile soil water (MSW) , and lateral subsurface flow. The depleted spring snowmelt and enriched summer rainfall formed tightly bound soil water and MSW, respectively. The dynamic mixing between tightly bound soil water and MSW resuted in BSW with more depleted and variable stable isotopic feature than MSW. 2) Along with the thawing of the frozen soil, surface runoff and shallowsubsurface flow (SSF) at 30&#8722;60 cm was the major flow pathway in the permafrost influenced alpine meadow hillslope during spring snowmelt and summer rainfall period, reapectively, with the frozen soil maintaining supra-permafrost water level. 3) Comparison between two neighouring catchments under similar precipitation conditions indicated that streamflow of the lower catchment with less permafrost proportion and earlier thawing time has larger SSF and higher based flow component, indicating the potential changes of hydrological regims subject to future warming.

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Elucidating sources and pathways of dissolved organic carbon in a small, forested catchment – A qualitative assessment of stream, soil and shallow groundwater

10.5194/egusphere-egu21-15785 ◽

2021 ◽

Author(s):

Katharina Blaurock ◽

Phil Garthen ◽

Benjamin S. Gilfedder ◽

Jan H. Fleckenstein ◽

Stefan Peiffer ◽

...

Keyword(s):

Organic Carbon ◽

Dissolved Organic Carbon ◽

Soil Water ◽

Riparian Zone ◽

Stream Water ◽

Shallow Groundwater ◽

Drinking Water Treatment ◽

Base Flow ◽

Qualitative Assessment ◽

Fluorescence Characteristics

Dissolved organic carbon (DOC) constitutes the biggest portion of carbon that is exported from soils. During the last decades, widespread increases in DOC concentrations of surface waters have been observed, affecting ecosystem functioning and drinking water treatment. However, the hydrological controls on DOC mobilization are still not completely understood.We sampled two different topographical positions within a headwater catchment in the Bavarian Forest National Park: at a steep hillslope (880 m.a.s.l.) and in a flat and wide riparian zone (770 m.a.s.l.). By using piezometers, pore water samplers (peepers) and in-stream spectrometric devices we measured DOC concentrations as well as DOC absorbance (A254/A365 and SUVA254) and fluorescence characteristics (fluorescence and freshness indices) in soil water, shallow ground water and stream water in order to gain insights into the DOC source areas during base-flow and during precipitation events.High DOC concentrations (up to 80 mg L-1) were found in soil water from cascading sequences of small ponds in the flat downstream part of the catchment that fill up temporarily. The increase of in-stream DOC concentrations during events was accompanied by changing DOC characteristics at both locations, for example increasing freshness index values. As the freshness index values were approaching the values found in the DOC-rich ponds in the riparian zone, these ponds seem to be important DOC sources during events. Our preliminary results point to a change of flow pathways during events.

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Altered Soil-Soil Water Interactions Inferred from Stream Water Chemistry at an Artificially Acidified Watershed at Bear Brook Watershed, Maine USA

The Bear Brook Watershed in Maine: A Paired Watershed Experiment ◽

10.1007/978-94-017-3241-3_4 ◽

1999 ◽

pp. 97-111 ◽

Cited By ~ 1

Author(s):

S. Norton ◽

J. Kahl ◽

I. Fernandez

Keyword(s):

Water Chemistry ◽

Soil Water ◽

Stream Water ◽

Stream Water Chemistry

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Spatial distribution of soils determines export of nitrogen and dissolved organic carbon from an intensively managed agricultural landscape

Biogeosciences ◽

10.5194/bg-9-4513-2012 ◽

2012 ◽

Vol 9 (11) ◽

pp. 4513-4525 ◽

Cited By ~ 18

Author(s):

T. Wohlfart ◽

J.-F. Exbrayat ◽

K. Schelde ◽

B. Christen ◽

T. Dalgaard ◽

...

Keyword(s):

Organic Carbon ◽

Dissolved Organic Carbon ◽

Agricultural Landscape ◽

Agricultural Land ◽

Stream Water ◽

Organic Soils ◽

Total N ◽

Small Catchment ◽

Landscape Characteristics ◽

Intensively Managed

Abstract. The surrounding landscape of a stream has crucial impacts on the aquatic environment. This study pictures the hydro-biogeochemical situation of the Tyrebækken creek catchment in central Jutland, Denmark. The intensively managed agricultural landscape is dominated by rotational croplands. The small catchment mainly consist of sandy soil types besides organic soils along the streams. The aim of the study was to characterise the relative influence of soil type and land use on stream water quality. Nine snapshot sampling campaigns were undertaken during the growing season of 2009. Total dissolved nitrogen (TDN), nitrate (NO3−), ammonium nitrogen and dissolved organic carbon (DOC) concentrations were measured, and dissolved organic nitrogen (DON) was calculated for each grabbed sample. Electrical conductivity, pH and flow velocity were measured during sampling. Statistical analyses showed significant differences between the northern, southern and converged stream parts, especially for NO3− concentrations with average values between 1.4 mg N l−1 and 9.6 mg N l−1. Furthermore, throughout the sampling period DON concentrations increased to 2.8 mg N l−1 in the northern stream contributing up to 81% to TDN. Multiple-linear regression analyses performed between chemical data and landscape characteristics showed a significant negative influence of organic soils on instream N concentrations and corresponding losses in spite of their overall minor share of the agricultural land (12.9%). On the other hand, organic soil frequency was positively correlated to the corresponding DOC concentrations. Croplands also had a significant influence but with weaker correlations. For our case study we conclude that the fractions of coarse textured and organic soils have a major influence on N and DOC export in this intensively used landscape. Meanwhile, the contribution of DON to the total N losses was substantial.

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The Evaluation of Soil Water Storage in A Small Catchment in 2009 And 2010

Acta Horticulturae et Regiotecturae ◽

10.2478/ahr-2014-0001 ◽

2014 ◽

Vol 17 (1) ◽

pp. 1-4

Author(s):

Ľuboš Jurík ◽

Tatiana Kaletová

Keyword(s):

Soil Water ◽

Soil Profile ◽

Water Storage ◽

Vertical Direction ◽

Field Capacity ◽

Mean Value ◽

Soil Water Storage ◽

Volumetric Soil Water Content ◽

Small Catchment ◽

High Precipitation Events

Abstract The soil water storage in a soil profile was calculated from the measured values of volumetric soil water content by the Profile Probe PR2/6 (Delta-T Device Ltd.) in the Bocegaj catchment in the depth up to 1m. The monitored season in the year 2009 followed after a dry season, and in the year 2010, rainfalls were above the average values. The soil water storage was higher than the mean value of field capacity during the season with high precipitation events. With a decreased amount of rainfalls, rising air temperature and crops growing, the soil water storage was in recession. In the vertical direction, the volumetric soil moisture as well as soil water storage in every soil profile have their characteristic progresses.

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How do meteorological variables and topography control species-specific water uptake strategy along a forested hillslope?

10.5194/egusphere-egu2020-6954 ◽

2020 ◽

Author(s):

Ginevra Fabiani ◽

Daniele Penna ◽

Julian Klaus

Keyword(s):

Isotopic Composition ◽

Soil Water ◽

Water Uptake ◽

Temporal Dynamics ◽

Growth Parameters ◽

Stream Water ◽

Growing Season ◽

Grab Sampling ◽

Spatio Temporal ◽

Species Specific

In the face of current global warming conditions, temperate forest ecosystems are expected to be strongly affected by temperature increase and more frequent and intense water shortage. This leads to severe stress for forest vegetation in many temperate systems. Therefore, understanding the vegetation water use in temperate forests is urgently needed for more effective forest management strategies. Root water uptake (RWU) is a species-specific trait (tree physiology and root architecture) and its spatio-temporal patterns are controlled by a range of site-specific (e.g., topography, geology, pedology) and meteorological factors (e.g., temperature, soil humidity, rainfall.In the present study, we use stable water isotopologues as ecohydrological tracers combined with continuous measurement of hydrometeorological (weather variables, groundwater levels, soil moisture, streamflow) and physiological (sap flow, radial stem growth) parameters to investigate the spatio-temporal dynamics of water uptake for beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Liebl) trees along a hillslope in a Luxemburgish catchment.Fortnightly field campaigns were carried out during the growing season (April-October) 2019 to sample water from xylem, soil water at different depths, groundwater, stream water, and precipitation. Soil water isotopic composition and xylem water were extracted via cryogenic distillation. Grab sampling was performed for the other water pools. The isotopic composition was determined through laser spectroscopy and mass spectrometry (for xylem samples only).From preliminary results, the isotopic composition of xylem water shows a marked seasonal variability suggesting a plasticity in RWU or a change in the isotopic composition of the water pools over the growing season. Moreover, beech and oak trees exhibit different uptake strategies when water supply is low. Within the range of observed groundwater variation topography does not play a statistically significant role on RWU.

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