Two Fixed Ratio Dilutions for Soil Salinity Monitoring in Hypersaline Wetlands

Herrero, J.; Weindorf, David C.; Álamo, Carmen Castañeda del

doi:10.1371/journal.pone.0126493

Cited by 18 publications

(21 citation statements)

References 91 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The qualitative test for sulfate is conducted in two steps: Prepare an extract of soil in water. Shake for 30 min and then let stand for an additional 24 h to guarantee the maximum dissolution of gypsum (Herrero, Weindorf, & Castañeda, 2015). As only 3 mL will be needed, an aliquot of an extract at 1:5 soil to water extract prepared for other purposes can be used. Filter the extract, take 3 mL and add 10 drops of 1 M HCl and then 2 mL of 1 M BaCl 2 . …”

Section: Individual Steps In the Preferred Analysis Including Justifmentioning

confidence: 99%

Soil gypsum determination

Herrero

Artieda

Weindorf

2020

Soil Science Soc of Amer J

View full text Add to dashboard Cite

The methods for gypsum content determination in soils are summarized and their applicability discussed. Special attention is given to the critical step of sample preparation, stressing the elimination of the oven heating at temperatures surpassing 40°C. Wet methods are unsuitable for soils rich in gypsum or containing other sulfates. Instead, oven‐based methods playing on the mass variations due to the release of constitutional water of gypsum are preferable. Under laboratory settings, we recommend two existing methods: one directly measuring the loss of mass on heating and the other exploiting the gypsum–bassanite phase change under controlled conditions. Both reflectance and X‐ray fluorescence (XRF) provide nondestructive methods for quick gypsum appraisal, and combining both methods increases the accuracy. The results are easily calibrated with gravimetric methods.

show abstract

Section: Individual Steps In the Preferred Analysis Including Justifmentioning

confidence: 99%

Soil gypsum determination

Herrero

Artieda

Weindorf

2020

Soil Science Soc of Amer J

View full text Add to dashboard Cite

show abstract

“…For the EC to be representative of the stock of soluble salts in the soil, complete ionic dissociation must be achieved, that is, ion pairs must be absent in the extracts. We verified this condition using the two fixed-ratio dilution approach as discussed in Herrero et al (2015).…”

Section: Soil Salinitymentioning

confidence: 79%

“…Electrical conductivity (EC) was used as a proxy for salinity. The soil salt stock was appraised using the two fixed-ratio dilution approach (Herrero et al, 2015), that is, preparing the aqueous extracts of all 33 soil samples at both 1:5 and 1:10 soil-towater dilutions (weight:weight) and measuring their EC (EC1:5 and EC1:10), expressed in dS m -1 at 25 ºC. Following the rationale in cAsby- Horton et al (2015), the particle size distribution of the samples was not determined in the laboratory, and the saturation percentage (SP) was considered a surrogate for textural composition.…”

Section: Laboratory Proceduresmentioning

confidence: 99%

“…We therefore propose the use of the OLS method in these circumstances, as its popularity will facilitate the checking of the coherence of analytical results in future years and the comparisons between samples taken on different dates. According to the rationale in Herrero et al (2015), the high R 2 values in the regressions of EC1:5 over EC1:10 (Table III) denote that the 1:5 extracts are free of either neutral ion pairs or those with other charges. This confirms the adequacy of EC1:5 in expressing the stock of soluble salts in the soil, at least within the EC1:5 ranges shown for Farrachuela in Table III.…”

Section: Directions For Future Appraisals Of the Soil Salt Stockmentioning

confidence: 99%

See 1 more Smart Citation

Salada Farrachuela, a saline wetland in Tamarite de Litera, Spain

Herrero-Isern

Castañeda

Velayos

2020

Boletín De La Real Sociedad Española De Historia Natural

Self Cite

View full text Add to dashboard Cite

This paper gives, for the first time, details of the vascular plants plus the soluble salts and other major components of their natural substrate in Salada Farrachuela, a hypersaline wetland located in the municipality of Tamarite, NE Spain. The wetland is situated on the outcropping evaporite-cored Barbastro Anticline, an area declared by the environmental authorities to be of community interest and part of the Natura 2000 network. This uncultivated and occasionally flooded wetland harbors plants able to withstand the conditions of their substrate whose upper layer (0–25 cm) has an average of 41% gypsum (CaSO4•2H2O), and 7.2 dS m−1 at 25 ºC electrical conductivity in 1:5 soil-to-water weight ratio (EC1:5) extracts. The EC1:5 value in the soil samples up to a depth of 2 m ranges from 6.23 to 7.95 dS m−1. At this depth, the average EC in the saturation extracts (ECe) is 37.0 dS m−1, with sulfate being the most abundant ion (503 meq L−1), followed by magnesium (492 meq L−1), sodium (113 meq L−1), and chloride (41 meq L−1). Salinity, hydric conditions, and halophilous vegetation contrast distinctly with the surrounding nonsaline gypseous land and its gypsophilous vegetation. This article provides a baseline for future investigations of the ecology of this wetland in relation to salinity, and a reference for the monitoring needed to guarantee its conservation. R esumen Este artículo da por primera vez noticia de las plantas vasculares y de las sales solubles y otros componentes mayoritarios del suelo de la Salada Farrachuela, un humedal hipersalino situado en el municipio de Tamarite de Litera, provincia de Huesca, en el NE de España. El humedal se localiza en el afloramiento del núcleo evaporítico del anticlinal de Barbastro, un área declarada de interés comunitario incluida en la Red Natura 2000. Este humedal, inculto e inundado ocasionalmente, alberga plantas adaptadas a un suelo cuya capa superior (0-25 cm) tiene por término medio un 41% de yeso (CaSO4•2H2O), 7.2 dS m−1 a 25 ºC de conductividad eléctrica en el extracto acuoso 1:5 en peso de suelo:agua (EC1:5). Para ese espesor de suelo, la conductividad eléctrica en extracto de saturación (ECe) a 25 ºC es 37.0 dS m−1, siendo el sulfato el ión más abundante (503 meq L−1) seguido del magnesio (492 meq L−1), sodio (113 meq L−1), y cloruro (41 meq L−1). La salinidad, las condiciones de humedad y la vegetación halófila contrastan fuertemente con las tierras circundantes, yesosas y no salinas. Este artículo puede ser un punto de partida para futuras investigaciones de la ecología del humedal en relación con la salinidad, y una referencia en el futuro seguimiento necesario para garantizar su conservación.

show abstract

“…In practice, EC does not have a linear relationship with concentration due to a number of factors, including: Ion specific charge differences in soils dominated by specific salt species (e.g. [ 64 ] Table 2 differences in EC 1:1 to EC e conversion due to specific salts), ion-pairing in which oppositely charged ions in solution can pair resulting in a net zero charge [ 65 ], diminished conductivity with increased solution concentration (the Debye-Hückel Theory of Electrolytes), incomplete salt dissolution due to salt-solution equilibrium for a specific salt species, and inadequate equilibration time for solubility of different salts (see [ 62 ] and their determination of EC stabilization time). Due to the complex interrelation of variables, conversion between results obtained using different methods is not recommended [ 66 ].…”

Section: Review Of Soil Salinity and Electrical Conductivity Measuremenmentioning

confidence: 99%

Soil analysis in discussions of agricultural feasibility for ancient civilizations: A critical review and reanalysis of the data and debate from Chaco Canyon, New Mexico

et al. 2018

View full text Add to dashboard Cite

Questions about how archaeological populations obtained basic food supplies are often difficult to answer. The application of specialist techniques from non-archaeological fields typically expands our knowledge base, but can be detrimental to cultural interpretations if employed incorrectly, resulting in problematic datasets and erroneous conclusions not easily caught by the recipient archaeological community. One area where this problem has failed to find resolution is Chaco Canyon, New Mexico, the center of one of the New World’s most vibrant ancient civilizations. Discussions of agricultural feasibility and its impact on local population levels at Chaco Canyon have been heavily influenced by studies of soil salinity. A number of researchers have argued that salinized soils severely limited local agricultural production, instead suggesting food was imported from distant sources, specifically the Chuska Mountains. A careful reassessment of existing salinity data as measured by electrical conductivity reveals critical errors in data conversion and presentation that have misrepresented the character of the area’s soil and its potential impact on crops. We combine all available electrical conductivity data, including our own, and apply multiple established conversion methods in order to estimate soil salinity values and evaluate their relationship to agricultural productivity potential. Our results show that Chacoan soils display the same salinity ranges and spatial variability as soils in other documented, productive fields in semi-arid areas. Additionally, the proposed large-scale importation of food from the Chuska Mountains region has serious social implications that have not been thoroughly explored. We consider these factors and conclude that the high cost and extreme inflexibility of such a system, in combination with material evidence for local agriculture within Chaco Canyon, make this scenario highly unlikely. Both the soil salinity and archaeological data suggest that there is no justification for precluding the practice of local agriculture within Chaco Canyon.

show abstract

Two Fixed Ratio Dilutions for Soil Salinity Monitoring in Hypersaline Wetlands

Cited by 18 publications

References 91 publications

Soil gypsum determination

Soil gypsum determination

Salada Farrachuela, a saline wetland in Tamarite de Litera, Spain

Soil analysis in discussions of agricultural feasibility for ancient civilizations: A critical review and reanalysis of the data and debate from Chaco Canyon, New Mexico

Contact Info

Product

Resources

About