Soluble Salts In Soil Research Articles

Soil remediation of degraded coastal saline wetlands by irrigation with paper mill effluent and plowing

Combined with anti-waterlogging ditches, irrigation with treated paper mill effluent (TPME) and plowing were applied in this study to investigate the effects of remediation of degraded coastal saline-alkaline wetlands. Three treatments were employed, viz., control (CK), irrigated with 10 cm depth of TPME (I), and plowing to 20 cm deep before irrigating 10 cm depth of TPME (IP). Results show that both I-treatment and IP-treatment could improve soil structure by decreasing bulk density by 5% and 8%. Irrigation with TPME containing low salinity stimulated salts leaching instead of accumulating. With anti-waterlogging ditches, salts were drained out of soil. Irrigation with 10 cm depth of TPME lowered total soluble salts in soil and sodium adsorption ration by 33% and 8%, respectively, but there was no significant difference compared with CK, indicating that this irrigation rate was not heavy enough to remarkably reduce soil salinity and sodicity. Thus, irrigation rate should be enhanced in order to reach better effects of desalinization and desodication. Irrigation with TPME significantly increased soil organic matter, alkali-hydrolyzable nitrogen and available phosphorus due to the abundant organic matter in TPME. Plowing increased soil air circulation, so as to enhance mineralization of organic matter and lead to the loss of organic matter; however, plowing significantly improved soil alkali-hydrolyzable nitrogen and available phosphorus. Improvements of physicochemical properties in I-treatment and IP-treatment both boosted soil microbial population and activity. Microbial biomass carbon increased significantly by 327% (I-treatment) and 451% (IP-treatment), while soil respiration increased significantly by 316% (I-treatment) and 386% (IP-treatment). Urease and dehydrogenase activities in both I-treatment and IP-treatment were significantly higher than that in CK. Phosphatase in IP-treatment was significantly higher than that in CK. Compared to I-treatment, IP-treatment improved all of the soil properties except for soil organic matter. The key to remediation of degraded saline-alkaline wetlands is to decrease soil salinity and sodicity; thus, irrigation plus plowing could be an ideal method of soil remediation.

Influence of Ionic Liquid 1- butyl-3-methylimidazolium Chloride on the Soil Micro-Ecological System

In order to evaluate the influence of ionic liquid 1- butyl-3-methylimidazolium chloride ([Bmim]Cl) on the soil micro-ecological system, the toxicity of [Bmim]Cl to soil microorganisms and its impact on soil physico-chemical properties were investigated. Three soil samples, which were taken from the rape land, nursery land and the broad bean land respectively, were used for this study. The toxicity test results show that the [Bmim]Cl inhibited the growth of soil microorganisms including bacteria and actinomycetes. This inhibition became stronger with the [Bmim]Cl concentration increasing. The EC50 of soil bacteria was close to that of the Vibrio fischeri, and the EC50 of soil actinomycetes was near to that of the Pseudokirchneriella subcapitata. The soil physico-chemical properties test results indicate that the organic mass and the soluble salts in soil increased with the increase of the [Bmim]Cl concentration. The [Bmim]Cl also caused the pH change in the soil micro-ecological system. It suggests that the ionic liquid [Bmim]Cl would influence the soil micro- ecological system by inhibiting the growth of soil microorganisms and altering the soil physico-chemical properties when it contaminated the soil system.

黑河下游土壤水盐对生态输水的响应及其与植被生长的关系

生态输水作为一项改善黑河下游生态环境的人工输水工程,研究土壤水盐与地表植被对输水的响应对于下游植被的恢复与重建具有重要的理论和实践意义。以2001年和2010年野外土壤和植物样方调查资料为基础,探讨了黑河下游土壤水盐对生态输水的响应及其与植被生长的关系,结果表明:(1)输水后不同深度土壤含水率的增加幅度依次为:胡杨林＞柽柳林＞草地;(2)不同群落土壤含盐量的增加幅度依次为:苦豆子＞柽柳＞梭梭＞胡杨;同时,土壤盐分主要以HCO₃^-和Na⁺为主的轻度盐化土向以SO₄^2-、Cl^-及Ca²⁺等为主的中度和强度盐化土转化;(3)以胡杨为例,土壤含水率小于6%时,密度和冠幅与土壤含水率呈正相关,但大于6%时,冠幅和密度分别介于40-70 m²和0.5-5株/100m²之间;同样,土壤水溶性盐含量小于1%时,密度和冠幅与土壤含水率呈正相关,但大于1%时,密度在0.5-5株/100m²之间,造成上述结果的原因更多是群落的一种"自然稀疏"现象。;The Heihe River is the second longest inland river in China. The eco-environmental problems of the oasis in the lower reaches of Heihe River have markedly deteriorated over the past several decades because of the comprehensive effects of a number of factors. These factors include the continuous decrease in the discharge water of the Heihe River, human and animal population growth, increase of socio-economic activities, and climate warming. Water deliveries have been conducted by the Heihe River Bureau since 2000 to address the existing eco-environmental problems. Several scientific and realistic issues concerning this significant artificial water delivery project include the response process and mechanism of the eco-environment involving vegetation restoration and reconstruction brought about by water deliveries in the lower reaches of Heihe River. The responses of soil water and salinity variation to water deliveries were presented based on the investigation of soil and plant plots in 2001 and 2010. This paper aimed to evaluate the variance in the soil moisture and soil-soluble salt content before and after water deliveries in the lower reaches of Heihe River. The relationship between soil moisture, as well as soil-soluble salt content, and vegetation growth variables was also determined. <br> The results indicated that the soil moisture content (SMC) increased at different depths after water deliveries in Heihe River. The rate of increase varied with the different types of communities and could be arranged in the following order:<em> Populus euphratica</em>＞<em>Tamarix chinensis</em>＞Herbal. Moreover, the soil-soluble salt content (SSC) increased after water deliveries at different depths because of the strong evaporation effects. The rate of increase could be arranged in following the order: <em>Sophora alopecuroides</em>＞<em>T. chinensis</em>＞<em>Haloxylon ammodendron</em>＞<em>P. euphratica</em>. In addition, it could be found in the conversion of soil salinity type from slightly saline soil dominated by HCO₃^- and Na⁺ to medium and intense saline soil mainly dominated by SO₄^2-, Cl^- and Ca²⁺. The average density and crown, with <em>P. euphratica</em> community as an example, increased with increasing SMC of less than 6%, in which these values ranged from 40 m² to 70 m² and 0.5 plants per 100 m² to 5 plants per 100 m² at an SMC of more than 6%, respectively. Similarly, the average density ranged from 0.5 plants per 100 m² to 5 plants per 100 m² with an SSC of more than 6%. However, the average crown did not decrease with an SSC of more than 6%. Therefore, we conclude that the self thinning process of the <em>P. euphratica</em> community, rather than the salt, caused stress to the plant growth.

Reaction of lime trees (Tilia sp.) growing along the Żwirki i Wigury Street in Warsaw on soil salinity caused by chemical technology of snow removal

The studies were focused on the influence of sodium chloride application in the chemical technology of snow removal from streets on the conditions of lime trees (Tilia sp.) growing along the Żwirki i Wigury Street in Warsaw and the determination of the degree of salinity on soils under street vegetation. The analyses show that chemical technology of soil removal causes changes in the soil environment. They include ionic imbalance of the soil solution and change of soil reaction. Electrical conductivity of the saturated soil extract also increases, as well as content of soluble salts in soils under street vegetation. Sodium chloride significantly influences the lime trees growing along the Żwirki i Wigury Street. Leaves growing directly near the street show severe effects of paralysis by sodium chloride in form of necrosis, discoloration (browning), and in consequence drying and premature leaf-fall.

Average concentration of soluble salts in leached soils inferred from the convective–dispersive equation

The convective-dispersive, or advective-dis- persive, equation (CDE) has long been the model of choice for solute transport in soils. Using the average concentra- tion of soluble salts in soil profile to evaluate changes in salinity due to irrigation can be beneficial when spatial variability of soil salinity at selected depths is larger than spatial variability of soil salinity in the layer encompassing these depths, and when soil salinity is evaluated with electric conductivity measurements that give layer-average rather than depth-specific salinity values. The objective of this work was to present analytical solutions of the CDE that express the average soluble salt content in soil profile as the function of time, water flux, and solute dispersion parameter. The solutions were developed for both semiin- finite and finite domain and implemented in a computer code. Examples are presented of using these solutions to develop a nomogram for the dispersion coefficient esti- mation and to evaluate the applicability of the semiinfinite domain solution to soil monolith leaching experiments. In cases when the CDE application is justified, the analysis of the salt leaching based on the average salt concentrations in soil profile provides estimates of the effective salt dis- persion parameter useful in land evaluation and soil

Reaction of lime trees (Tilia sp.) growing along the Żwirki i Wigury Street in Warsaw on soil salinity caused by chemical technology of snow removal

The studies were focused on the influence of sodium chloride application in the chemical technology of snow removal from streets on the conditions of lime trees (Tilia sp.) growing along the Żwirki i Wigury Street in Warsaw and the determination of the degree of salinity on soils under street vegetation. The analyses show that chemical technology of soil removal causes changes in the soil environment. They include ionic imbalance of the soil solution and change of soil reaction. Electrical conductivity of the saturated soil extract also increases, as well as content of soluble salts in soils under street vegetation. Sodium chloride significantly influences the lime trees growing along the Żwirki i Wigury Street. Leaves growing directly near the street show severe effects of paralysis by sodium chloride in form of necrosis, discoloration (browning), and in consequence drying and premature leaf-fall.

Yield Response of Herbs to Nitrogen and Potassium in Sand in Multiple Harvests

ABSTRACT Yield potential of Italian parsley (Petroselinum crispum), Russian tarragon (Artemisia dracunculus), sweet marjoram (Origanum majorana), and thyme (Thymus vulgaris) was evaluated in multiple harvests from 1993 to 1995. The herbs were grown using a full-bed polyethylene mulch-seepage irrigation system with three nitrogen and potassium rates. In the 1993–94 growth season, plant survival of sweet marjoram and thyme, but not Italian parsley and Russian tarragon, was adversely affected by an increase in soil soluble salt concentrations as the season progressed. Fresh weight yields of sweet marjoram and Italian parsley in the first two harvests of the 1993–94 growth season were maximized at 49 or 98 kg nitrogen/ha and 40 or 80 kg potassium/ha. Maximum Russian tarragon fresh weight yield occurred at 147 kg nitrogen/ha and 120 kg potassium/ha (P < 0.05). Yields of thyme were similar in all harvests at the three nitrogen and potassium rates tested. In the 1994–95 growth season, early fresh weight yields of sweet marjoram, Italian parsley, and thyme were best with the 98 kg nitrogen/ha and 80 kg potassium/ha levels and Russian tarragon fresh weight yields were best at nitrogen and potassium levels similar to the first test year. Nitrogen and potassium rates had little to no effect on macroelement concentrations in herb shoots.

Evaluation of fly ash as a soil amendment for the Atlantic Coastal Plain: II. Soil chemical properties and crop growth

Crop yields in the Atlantic Coastal Plain of the U.S.A. are limited by the low moisture-holding capacities of the sandy soils common to the region. Corn was grown in a Hammonton loamy sand soil amended with fly ash (0, 5, 10, 20, 30, and 40%) to determine if the ash rates required to improve soil moisture holding capacity would adversely affect plant growth, or soil and plant levels of nutrients and heavy metals. Fly ash increased soil test levels of P, K, Ca, Mg, Mn, Cu, Zn, B, Cd, Cr, Ni, and Pb. Nutrient concentrations in plants grown in the ash-amended soils, except P, Mn, and B, remained within established sufficiency ranges. The 20 and 40% ash rates increased soil soluble salt (EC) levels from 0.2 to 1.1–1.5 and 1.7–2.1 mmho cm−1, soil pH from 5.6 to 6.0–6.4 or 6.3–6.9, and extractable B from 0.2 to 2.2–5.9 and 2.2–9.0 mg kg−1. Fly ash reduced corn germination, delayed seedling emergence, and reduced root and shoot dry weights. Plant B concentrations at the 40% ash rate were in the phytotoxic range (136–189 mg kg−1). Management practices that allow for pre-leaching of B and soluble salts will likely be required to attain satisfactory corn growth in ash-amended soils.

Soils and surface water quality in northeastern Scotland

ABSTRACTThe nature of soil-water interactions is discussed in the context of both soil formation and drainage water chemistry. The interacting factors regulating drainage water chemistry are then briefly considered, including soil type and parent material, soil atmosphere CO2 concentration, hydrological pathways, soluble salts, topography, climate and biotic effects. Based upon these factors, some sites in NE Scotland thought to be highly susceptible to water acidification are examined, and the low pH of their waters is confirmed. The acidity trends of two superficially similar streams apparently less at risk are compared, and the differences explained in terms of sub-surface soil characteristics. The possible impacts of both afforestation and of acidifying pollutants on water pH are considered briefly where appropriate.

Lightmicroscope and submicroscope observations of salts in marine alluvium (India)

In samples from a salt-affected Indian soil series, a curly stem-like salt efflorescence occurred. Unimpregnated soil material and thin sections from these samples, prepared in two different ways, were studied with lightmicroscopy and submicroscopy. The samples came from the Dandi soil series, classified as Halaquepts (Soil Survey Staff U.S.D.A., 1975), which occur extensively on marine alluvium in the semi-arid parts of Gujarat (India). In the unimpregnated samples, several habits of halite (massive crusts, cubical forms, thin threads and curly stem-like forms) were determined with SEM—EDXRA. In large thin sections ( 8 × 15 cm ) covered with a thin glass slide, which could only be studied under a lightmicroscope, no halite was observed. However, another salt of unknown composition, not observed in unimpregnated soil material, was detected. In addition, in small thin sections ( 2 × 3 cm ) with highly polished surfaces, remnants of halite could be observed under the lightmicroscope. With submicroscopy the presence of halite was confirmed and the unknown salt was proved to be a habit of gypsum. This gypsum forms roughly circular shapes, that have diameters varying between 80–200 μm, cracked surfaces and diffuse extinction patterns under crossed polarizers. It occurs along void walls, often in association with halite and in the fine-grained groundmass near voids. Halite occurs along void walls and as angular grains in coarse-grained laminae. The habit of the gypsum observed and the curly stem-like halite on the unimpregnated soil material, have not previously been reported in the literature. The habits of halite need not all be pedogenetic; though the gypsum, a much less soluble salt, probably is pedogenetic. Techniques of preparing thin sections must be improved for the further study of easily soluble salts in soils.

A theoretical examination of Burns' (1975) equation for predicting the leaching of nitrate fertilizer applied to a soil surface

SUMMARYThe modelling of the redistribution of soluble salts in soils, in which it is assumed that the amount of water transferred from layer to layer is related to the excess over field capacity of the water content of a layer, is critically examined.The equation obtained from the dispersion equation by neglecting the diffusive term is solved for the leaching of surface-applied nitrates. It is shown that, by comparing the finite-difference form of this equation to the algebraic formulation of Burns' (1975) model, the two approaches are essentially the same, but that Burns makes approximations that are too inaccurate. In particular, it is incorrect to relate the transfer of water to the excess over the field capacity of the water content of the layer. Burns' model, when applied correctly, requiresmany calculations to be performed, which is costly of computer time. However, it is unnecessary in this problem as the analytic solution is simple and quick to apply.

Horizontal variability of some soil properties within homogeneous stands of coastal salt meadow vegetation

Eighty soil samples, from the depth of 0–8 cm, taken at random within eight stands of homogeneous salt meadow vegetation along the shores of the Baltic in Denmark, were analysed for bulk density, content of organic matter, actual water content, pH, and for soluble salts, expressed by specific conductivity and waterextractable Na, K, Ca and Mg. For each stand and soil parameter the horizontal soil variability was expressed by the coefficient of variation. It was found, that the variability was higher in the upper than in the lower geolittoral stands, and that it was higher in the soil soluble salts than in the physical soil parameters. Differences in the ratios between the actual values of the individual soil parameters, expressed by co–variance, were found to be a further aspect of soil variability within the stands. The relationships between number of samples, coefficient of variation and analysis precision were discussed.

Response of Okra to Plant Density and Fertilization1

Abstract Plant density of okra (Hibiscus esculentus L. cv. Clemson Spineless) was varied from 16, 32, to 64 plants/m2 using 1 or 2 rows/bed and 2.5 or 5 cm in the row spacing. Yield per unit area increased linearly with plant density on a double logarithmic scale. Plant density and pod size were inversely related while the percent marketable pods were unaffected by treatments. The fertility rate did not affect yield responses, but the higher rate increased soil soluble salts, K, and NO3.

The Effect of Soil Soluble Salts and Cultural Practices on Mite Populations on Hothouse Tomatoes

Journal Article The Effect of Soil Soluble Salts and Cultural Practices on Mite Populations on Hothouse Tomatoes Get access J. G. Rodriguez, J. G. Rodriguez Ohio Agricultural Experiment Station, Wooster Search for other works by this author on: Oxford Academic PubMed Google Scholar R. B. Neiswander R. B. Neiswander Ohio Agricultural Experiment Station, Wooster Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Economic Entomology, Volume 42, Issue 1, 1 February 1949, Pages 56–59, https://doi.org/10.1093/jee/42.1.56 Published: 01 February 1949

Creosote Bush and the Lower Sonoran Zone of the Southwest

Creosote Bush (Larrea divaricata Cav.)I is among most reliable of indicators of natural biologic areas in Southwest, delimiting Lower Sonoran Zone fairly sharply. The recent articles2 on effect of sustained subzero weather upon Larrea in Virgin River Valley of Utah suggest certain earlier studies made upon this shrub. For more than half a century this remarkable Sonoran species has commanded ecological, distributional, chemical, as well as systematic, studies from a score of workers. Among earliest of these investigations was that published by J. M. Stillman in 18803 upon chemical nature of gum secreted by Larrea stems. Recent digests of systematic and broad ecologic status of shrub have been drawn up by Shreve in 19314 and by Jepson in 1936.5 Volney M. Spalding treated relation of Creosote Bush to water supply with particular reference to Arizona.6 Shreve and Mallery have reported on work in progress upon controlling factors limiting distribution of shrub.7 They report substantial differences in environment exist within space occupied by a single individual. Accordingly, it is difficult to assign determining agency limiting distribution, even over a small portion of its range in Southwest. Osmotic values for leaves have been determined by Mallery8 and their relation to soluble salts in soils, mechanical and chemical nature of soil and influence of rainfall and soil moisture, both through day and seasonally. Material for these osmotic studies was collected over practically entire range of Creosote Bush in Southwest. As has been pointed out several times occurrence of Larrea over thousands of square miles of arid or desert country, where it is often a dominant species showing considerable physiological elasticity in its habitat requirements, is proof that it is one of most successful of desert perennials. The fact has been pointed out by Shreve9 that this small-leaved nonsucculent evergreen lacks anatomical characters common to desert plants in general that favor conservation of water. Shreve says the adjustments

The Formation, Evolution, Reclamation, and the Absorbed Bases of Alkali Soils

Summary1. The formation of alkali soils is primarily a question of soluble salt accumulation. Those processes which bring about the accumulation of soluble salts in soils also tend to cause the accumulation of CaCO3. Under certain conditions simple calcium silicates may also be precipitated in alkali soils. Hilgard's researches were concerned chiefly with the soluble salts. On the other hand, more recent investigators have emphasised the base-exchange aspects of the subject. Sodium salts tend to react with the clay and humus constituents of the soil, converting them into Na-absorption compounds. These components produce extremely adverse conditions in the soil.2. Under certain conditions alkali soils tend to pass through four evolutionary stages, namely, salinisation, alkalinisation, desalinisation, and degradation. As to whether or not an alkali soil will pass beyond the salinisation stage, depends on the composition of the soluble salts that accumulate in it. Where sodium salts predominate, more or less alkalinisation of the exchange complex has taken place. However, this is not true where soluble calcium is relatively abundant.3. Desalinisation (by leaching, whether natural or artificial) of alkalinised soil is usually accompanied by the formation of Na2CO3and by pronounced deflocculation. If CaCO3be present, the formation of Na2CO3is accompanied by the replacement of absorbed sodium by calcium. Under these conditions the degradation stage will not be attained. If CaCO3be absent, base-unsaturated constituents arise under leaching conditions, and more or less of the inorganic-exchange complex becomes decomposed into simple oxides.