Leaching Of Salts Research Articles

COMPOSTING PROCESS IN THE PRODUCTION OF LETTUCE SEEDLING SUBSTRATES: EFFECT OF COVERING AND TURNING FREQUENCY

ABSTRACT The composting of waste from a broiler chicken production chain (BCPC) promotes the mitigation of environmental impacts and allows the commercialization of compost as an agricultural input. Both the characteristics and the potential for use of the final compost depends on the operational conditions during composting. The objective of this study was to evaluate the use of organic compounds generated from composting BCPC residues and the pruning debris of urban trees in the germination and initial growth of lettuce seedlings. Six organic substrates obtained under different coverage conditions (presence and absence) and number of turns (8, 12, and 16) were evaluated using the germination index (IG) and Dickson quality index (DQI) for the production of seedlings in trays and compared with a commercial substrate. Principal component analysis demonstrated that the IG is not related to the DQI. The compounds produced without coverage showed lower levels of electrical conductivity (p < 0.05) and potassium (p < 0.05) due to the leaching of soluble salts during composting. These substrates did not inhibit seed germination (IG ≥ 75%), but resulted in less robust seedlings, mainly in relation to the aerial portion. BCPC residues were viable for composting treatment and the DQI of the organic compounds (0.0125) used as substrates for the initial growth of lettuce seedlings were, on average, 14% higher than that obtained from the commercial substrate (0.090), indicating that the organic compounds were of better quality.

Chemical Evolution and Formation Mechanism of Groundwater in Hetao Irrigation Area

Groundwater resources are important sources of water in the arid region of northwestern China, but their overexploitation and utilization has led to a series of ecological and environmental problems. Exploring the characteristics and mechanism of groundwater chemical evolution is important for the rational use of groundwater resources. The characteristics of groundwater chemical evolution were studied in the Yongji Irrigation Area of Hetao Irrigation District and the formation mechanism of the chemical compounds in groundwater were investigated using cluster analysis, factor analysis, and other statistical methods. The influence degree of different factors was calculated. The results showed that the major cations in groundwater in the study area were Na+ and K+, and the major anions were Cl- and HCO3-. Moreover, Na+, K+, and Cl- showed high spatial variability and were the main factors contributing to groundwater salinization. The major chemical compounds in the groundwater in the study area were Cl-Na, HCO3 ·Cl ·SO4-Na, and HCO3-Na. Based on the cluster analysis results, the groundwater was divided into four categories (A1, A2, B1, and B2), of which A1 was highly mineralized by Cl-Na type water, while A2, B1, and B2 were mainly HCO3 ·Cl ·SO4-Na and HCO3-Na type water. Principal component analysis results suggest that groundwater chemistry was mainly affected by salinization, carbonate karstification, and human activities with the influence degrees of 45.976%, 23.853% and 16.678%, respectively. Evaporation, salt rock dissolution, and cation exchange were important sources of Na+ and Cl- accumulation in the irrigation area. Agricultural irrigation (leaching of soil salts) and drought (intense transpiration) were the key drivers of groundwater salinization in the irrigation area.

Effect of Saline Water Irrigation and Growing Media on Growth, Physiological and Mineral Parameters of Clove Pink Dianthus Caryophyllus

Soil salinity is one of the major environmental factors limiting plant growth and development; and it is considered a problem in arid and semiarid regions, where rainfall is insufficient to leach salts. The clove pink, Dianthus caryophyllus L. is a major product in Jordan with different irrigation needs and has the capacity to cope with water deficit. Consequently, the current study aimed at investigating the effect of salinity on certain growth, physiological and mineral parameters of two varieties of D. caryophyllus (Bizet Sagr and Grand Slam Hygr). The experiments were conducted under greenhouse conditions at the University of Jordan during the 2015/2016 growing season. The plants were grown in either soil or zeolitic tuff at five salinity levels. The results indicated that the growth parameters of both D. caryophyllus varieties vary significantly among the different salinity levels in both growing media. Increasing salinity caused a significant reduction in plant height, fresh and dry weights, flower length and diameter, and a delayed flowering time. Increasing salinity level caused also a significant reduction in leaf greenness, fluorescence yield, and relative water content, and increased stomatal resistance of both plant varieties in both growing media. Increasing salinity level caused a significant increase in Na and Cl, and a decrease in K, P, and N concentrations in plants of both tested varieties and media. In conclusion, salinity caused a significant effect on all tested growth, physiological and mineral parameters of D. caryophyllus. An appropriate irrigation regime should be used as a key to success in ornamentals’ growth control.

Policy-Driven Sustainable Saline Drainage Disposal and Forage Production in the Western San Joaquin Valley of California

Environmental policies to address water quality impairments in the San Joaquin River of California have focused on the reduction of salinity and selenium-contaminated subsurface agricultural drainage loads from westside sources. On 31 December 2019, all of the agricultural drainage from a 44,000 ha subarea on the western side of the San Joaquin River basin was curtailed. This policy requires the on-site disposal of all of the agricultural drainage water in perpetuity, except during flooding events, when emergency drainage to the River is sanctioned. The reuse of this saline agricultural drainage water to irrigate forage crops, such as ‘Jose’ tall wheatgrass and alfalfa, in a 2428 ha reuse facility provides an economic return on this pollutant disposal option. Irrigation with brackish water requires careful management to prevent salt accumulation in the crop root zone, which can impact forage yields. The objective of this study was to optimize the sustainability of this reuse facility by maximizing the evaporation potential while achieving cost recovery. This was achieved by assessing the spatial and temporal distribution of the root zone salinity in selected fields of ‘Jose’ tall wheatgrass and alfalfa in the drainage reuse facility, some of which have been irrigated with brackish subsurface drainage water for over fifteen years. Electromagnetic soil surveys using an EM-38 instrument were used to measure the spatial variability of the salinity in the soil profile. The tall wheatgrass fields were irrigated with higher salinity water (1.2–9.3 dS m−1) compared to the fields of alfalfa (0.5–6.5 dS m−1). Correspondingly, the soil salinity in the tall wheatgrass fields was higher (12.5 dS m−1–19.3 dS m−1) compared to the alfalfa fields (8.97 dS m−1–14.4 dS m−1) for the years 2016 and 2017. Better leaching of salts was observed in the fields with a subsurface drainage system installed (13–1 and 13–2). The depth-averaged root zone salinity data sets are being used for the calibration of the transient hydro-salinity computer model CSUID-ID (a one-dimensional version of the Colorado State University Irrigation Drainage Model). This user-friendly decision support tool currently provides a useful framework for the data collection needed to make credible, field-scale salinity budgets. In time, it will provide guidance for appropriate leaching requirements and potential blending decisions for sustainable forage production. This paper shows the tie between environmental drainage policy and the role of local governance in the development of sustainable irrigation practices, and how well-directed collaborative field research can guide future resource management.

Sulfurization, acid-sulfate soils and active layer monitoring at the semiarid Seymour Island, Antarctica

Soils and permafrost occurrence and behavior at the Weddell Sea zone, located in the key zone of climatic transition between Maritime Antarctica and Continental Antarctica, remain little studied. We studied the main chemical, physical and mineralogical properties of representative soil profiles of the northern part of Seymour Island, discussing soil formation processes and the active-layer thermal and water regimes of a representative site. Soil sampling and installation of the monitoring site was carried out in the northern part of Seymour Island. Permafrost was generally detected within the first 100 cm of depth, except at coastal areas, although typical periglacial features (cryoturbation), vegetation growth and organic matter accumulation were negligible or absent. Well-drained soils showed low Electric Conductivity (EC), indicating leaching of salts, whereas near-permafrost layers showed higher values of EC. Salt content and EC increased at lower altitudes. Two major groups of soils were identified: (i) Acid Sulfate Soils (ASS); and (ii) Weakly Developed Alkaline Soils (WDAS). Acid Sulfate Soils develop under the influence of sulfide-containing material under oxidizing conditions, and are the most developed and weathered in the area, presenting significant morphological, mineralogical and chemical traits, such as low pH values, sulfuric B horizons, and the presence of secondary minerals indicating sulfurization process, such as jarosite and low crystallinity iron oxide. Weakly Developed Alkaline Soils develop under low chemical and mineralogical transformation, where physical weathering is a key process. These soils present high pH and high content of primary minerals in the clay fraction, mainly K-feldspars and plagioclase. The active-layer thermal regime is typical of periglacial environments, with seasonal temperature variations of soil around 0 °C, with prevailing negative temperatures. Regional climate was comparable with Continental Antarctica, whereas the pedoclimate (active layer thickness, soil water content) showed closer affinity with Maritime Antarctica. Some soil forming processes are driven by pedoclimate, and favored by the unfrozen and free-drainage conditions during the summer season; however, the main factor influencing soil development is parent material. The main soil formation processes are sulfurization, cryoclasty and halomorphism, since the semiarid dry climate does not favor cryoturbation and organic matter accumulation.

Assessment of Groundwater Quality for Different Aquifers in Halaib and Shalatien Area at South Eastern Desert of Egypt تقییم جودة المیاه الجوفیة للخزانات الصخریة الجوفیة المختلفة فى منطقة حلایب وشلاتین جنوب الصحراء الشرقیة – مصر

This work aims at assessing the groundwater quality in Halaib and Shalatien area, the main water resource for irrigation and civic utilization is groundwater (springs and wells). The groundwater aquifers in this area could be classified into three aquifer systems according to their litho-stratigraphic as follows: Fractured basement aquifer system, Nubian sandstone aquifer system and Quaternary aquifer system. 13 samples from different aquifer systems were taken in the study area; four samples were taken from groundwaters of fractured basement aquifer, eight from the Nubian sandstone aquifer and one from the Quaternary aquifer. Assessment in terms of salinity and sodicity hazards according to USDA (1954). Evaluation of groundwater quality using irrigation water quality index (IWQI) method was established by Meireles et al. (2010) for agricultural purposes with help of the Geographic Information System (GIS) technique. Five chemical parameters were utilized to calculate the IWQI including EC, Na+, Cl-, HCO3- and SAR. The IWQI map results showed that 46.2 % of the samples classified as low restricted are suitable for irrigation directly without any processing, 23.1% of the samples classified as moderate to highly restricted and can be used only in soils with high permeability values, recommended leaching of salts to avoid soil degradation. The remaining (30.7%) of the studied samples classified as severe restricted are suitable only for soils that have high permeability values applied the excess of water for leaching to avoid the accumulation of salt. In brief, these samples should be avoided its use for irrigation under normal conditions.

Soil solution composition affects microstructure of tropical saline alluvial soils in semi-arid environment

The remediation of soils stressed by salinity improves soil quality for food production. However, information on how remediation techniques affect microstructural stability/elasticity and resistance is lacking. Hence, the objective of this study was to characterize the microstructure of saline alluvial soils from a semi-arid environment, and to evaluate how the techniques of leaching soil and Na+ substitution by other cations affect the microstructure strength and elasticity evaluated by rheological techniques. Homogenized soil of sixteen horizons of four salinized soil profiles (an Abruptic Solonetz, a Eutric Gleysol, and two Hypereutric Planosols) were collected in Northeast of Brazil. Each horizon was analyzed separately in a completely randomized design, with three replications. The treatments corresponded to soils saturated with 1 × 10−4 mol m−3 of KCl (+K), CaCl2 (+Ca) or MgCl2 (+Mg), leaching of salts (LS) by successive leaching with alcohol 60%, and untreated soil (control). The soils were submitted to an amplitude sweep test with controlled strain in a compact modular rheometer. The obtained variables were strain and stress at the end of the linear viscoelastic interval (LVR) (γLVR and τLVR, respectively), strain (γYP) and stress (G’YP) at the yield point, shear stress (τmax), and integral Z (Iz). The rheological properties varied greatly between the horizons of the same soil profile. The LS increased γLVR compared to control, while the saturation with cations caused reduction in γLVR, especially in soils of higher clay content. The saturation with saline solution increased γYP and Iz, with greater effect in + K treatment. Both leaching of salts and cation saturation increased soil shear strength at the end of the LVR and at the yield point. Leaching of salts caused destabilization of soil microstructure, which is an important finding that needs to be addressed by measures accompanying remediation of salinized soils to maintain soil physical quality.

Experimental investigations on geopolymer stabilised compressed earth products

The main objective of the study was to explore the geopolymers to produce the compressed earth bricks for building construction. The paper presents the results of experimental investigations on geopolymer stabilised compressed earth specimens. The variables considered include, alkali concentration, clay content and percentage of ground slag and fly ash. The mix proportions of the variables were varied to assess optimum dosages for producing geopolymer stabilised compressed earth bricks. The results showed that the natural clay minerals in the soil do not yield sufficient strength. Use of ground slag and fly ash as an additional source of alumina and silica resulted in sufficient strength gain for the compressed earth specimen. The geopolymer stabilised compressed earth specimens showed efflorescence due to leaching of salts and the investigations showed that the efflorescence does not affect the strength. The products formed in the geopolymer stabilised compressed earth specimens were identified by employing the FTIR, XRD and NMR techniques.

The extraction of Ta, Nb and rare earths from fergusonite by using KOH sub-molten salt leaching

It is very important to efficiently extract Ta, Nb and rare earths from polymetallic ore such as fergusonite. A new method combining an alkaline leaching of sub-molten salt (SMS) and an acid leaching is recommended for extracting Ta, Nb and rare earths from fergusonite concentrate using an environmentally friendly process.The leaching yields of Ta and Nb from the concentrate reached to 98% and 99%, respectively under the most suitable KOH SMS leaching conditions, KOH concentration 80 wt%, leaching temperature 300C, KOH to concentrate mass ratio 3, stirring speed 800 rpm, leaching time 1 h. The overall recovery of Ta and Nb were 96% and 97%, respectively, and the total content of Ta and Nb in the crude Ta-Nb product was 98.6% (45.1%-Ta2O5, 53.5%-Nb2O5) when the solid to liquid mass ratio in the diluting stage was 1:2 and KOH concentration in the evaporating concentration stage was 30 wt%. The recovery yield of rare earths (96.5%-RE2O3) reached to 92% when the KOH SMS leach residue was leached with 15 wt% HCl solution.

Production of a Stable Building Material by Treatment of MSWI Bottom Ash with the Tauw EquiAsh® Process

A process called EquiAsh® was developed and tested on a large scale. This process aims at upgrading incinerator bottom ash into a long term environmentally safe and stable product. Driven by the agreement between the incinerator branch and the Dutch government in a ‘Green Deal’, the leaching behavior of bottom ash needs improvement. The leaching of metals and salts must be lowered. EquiAsh®, which is a combination of carbonation (accelerated aging), washing and further mineralization, realizes a safe and stable product now and in the future. The bottom ash is in equilibrium with the atmosphere and the pH is stabilized at values around 8.5. Large scale experiments with 1.000–1.300 ton incinerator bottom ash are performed. These experiments give insight into the changes in leaching of metals and salts. In the end, the bottom ash fulfills the Dutch leaching criteria for a freely applicable building material.

Identification of hydrochemical processes using multivariate statistics in a complex aquifer system of Sohag region, Egypt

Spatial variation of hydrochemical groundwater parameters indicates that the chemistry is ruled by complex process interactions (mixing of natural and anthropogenic processes). For this approach, analysis of 32 groundwater wells was conducted. Anthropogenic-influenced surface recharge and geogenic processes such as silicate weathering and redox process are identified by multivariate statistics, principal component analysis (PCA) and cluster analysis (CA). Surface water recharge tops the list of factors affecting groundwater chemistry in the Sohag area. The main recharging sources are leaching of salts of overlain soils and irrigation canals associated with anthropogenic impacts such as domestic sewage and agricultural nutrients. The excess of SO42− and HCO3− relative to Ca2+ in the semiconfined shallow aquifer at the floodplain can be attributed to the anthropogenic influence, infiltrated irrigation water and wastewater. On the other hand, in deep wells at the desert fringes, the deficiency of SO42− relative to Ca2+ concentration (however the dissolution of gypsum modeled by MINTEQ) is evidence on sulfides precipitation under reducing conditions as confirmed by the PCA analysis. Ion exchange on clay is another possible reason responsible for the deficiency of Ca2+ + Mg2+/SO42− + HCO3− relative to Na+/Cl− in semiconfined aquifer. Different water types (Na–Cl, Ca–Cl, Mg-–Cl and Na–HCO3) indicate different ion exchange processes formed due to varying contacts between freshwater and saline water. Excessive Mn/Fe ratio is attributed to fertilization and redox processes. Results enable the spatial separation of wells under semiconfined hydraulic conditions recharged by infiltrated irrigation water, from those under unconfined conditions recharged by seepage water leaching salty soils. Accordingly, different water types and values of salinity are complex and could be identified and spatially separated using AqQa and statistical analysis.

Evaluation of irrigation water salinity and leaching fraction on the water productivity for crops

In arid and semi-arid irrigated croplands, the excessive accumulation of soluble salts in the root zone is an extensive problem that seriously limits crop yield and water productivity (WP). To avoid affects the yield potential of crops, the application of extra irrigation for leaching of excessive salts from the root zone was required. Quantitative knowledge of effects of the irrigation water salinity and leaching fraction (LF) on the relative yield (RY) and the unit water productivity of crop evapotranspiration (UWPET) and the unit water productivity of irrigation water (UWPI) were becoming gradually important. This article provided theoretical models for estimating the UWPs (UWPET and UWPI) and optimizing leaching fraction according to irrigation water salinity. In the present study, eight levels of irrigation water salinity (ECw = 0.25, 0.50, 0.75, 1, 2, 3, 4, and 5 dS/m) and 39 levels of LF values ranging from 0.04 to 0.80 were set and tested to assessing their effects on the RY and UWPs for four typical crops (barley, bean, wheat, and maize) with different salt tolerance levels. Almost every curve determined between the UWPs and LFs for the four crops had an inflection point. It was indicated that the UWPET and UWPI could be maximized by optimizing the LF under different irrigation water salinities. Furthermore, the linear regression relationships were established to estimate the maximum values of UWPs and their corresponding optimal LFs for four crops by using the irrigation water salinity. Moreover, the theoretical models for estimating the UWPs were validated by data of wheat from previous literature, and the models could be suitable with acceptable relative errors when LFs ranging from 0.07 to 0.17. Keywords: irrigation water salinity, leaching fraction, salt-tolerant crop, salt stress, crop yield, water productivity DOI: 10.25165/j.ijabe.20201301.5047 Citation: Ning S R, Zhou B B, Wang Q J, Tao W H. Evaluation of irrigation water salinity and leaching fraction on the water productivity for crops. Int J Agric & Biol Eng, 2020; 13(1): 170–177.

Can conjunctive use of gypsum, city waste composts and marginal quality water rehabilitate saline-sodic soils?

Soil sodicity is major stress limiting crop production in the arid and semi-arid regions where groundwater contains excess salts with variable sodium adsorption ratio (SAR). This study investigated the impact of farmyard manure (F) and city compost in conjunction with gypsum to rehabilitate saline-sodic soil having pH1:2 (10.7), electrical conductivity (EC1:2; 3.09 dS m−1) and exchangeable sodium (70.3 %). Soil amended with gypsum (25 and 50 % of gypsum requirement, GR) and/or with 10 t ha−1 F (GR25 F), Karnal (GR25 K) and Delhi compost (GR25D) were incubated at moisture ∼60 % maximum WHC. One month incubated soils were sequentially leached up to ten pore volumes using saline water of SAR 5 and 15 with constant EC (6 dS m−1). The increment in SAR of applied water reduced the cumulative loss of Ca2+, Mg2+, and K+ and increased the release of Na+. Application of amendments and intense leaching decreased the soil pHs, ECe and alkalinity. Leaching with SAR 5 water decreased SAR of soil saturation extract to 9.7 compared with SAR 15 (17.2). Gapon’s selectivity coefficient (KG) pointed to the greater (0.017) adsorption preference of Ca2+ and Mg2+ in the soil leached with SAR 15 than SAR 5 (0.014) water. Reclamation depends on inherent soil ESP and supply of Ca2+ for exchange phase; KGbecomes more prioritized when SAR 15 water applied for leaching. Therefore, conjunctive use of gypsum (GR25) with compost is as effective as gypsum (GR50) on decrement of soil pHs and leaching of soluble salts.

Determination of the major geochemical processes of groundwater along the Cretaceous-Tertiary boundary of Trichinopoly, Tamilnadu, India

The hydrogeochemical variations in groundwater are mainly influenced by lithology, residence time of water in the aquifer matrix, and anthropogenic activities. This study was focused on the geochemical variations of groundwater in different lithological units (Archaean, Cretaceous, Tertiary, and Quaternary) by understanding the major factors governing the geochemical variations in each lithology. The 71 groundwater samples were collected from these rock types, namely, Archaean (14), Cretaceous (37), Tertiary (11), Quaternary (9). The collected samples were measured for major ions and they were used for preparation of standard geochemical plots and ionic ratios. Factor analysis and factor score were used to identify the major factors controlling the hydrochemistry and their spatial distribution in the study area. In addition, geochemical model, WATEQ 4F was used to determine the saturation condition of carbonate and sulphate minerals in the groundwater. Na–Cl and mixed Ca–Na–HCO3 were the dominant hydrochemical facies irrespective of lithological units. The overall interpretation of geochemical data revealed that leaching of secondary salts, weathering and ion exchange reaction along the groundwater flow path through various lithological units, and anthropogenic influence from domestic sewages and agricultural activities constitute the major geochemical processes in the study area. Hence, this study brings out the multiple hydrogeochemical process in the complex geological terrain along the Cretaceous-Tertiary boundary.

Micromorphological features of soils of semidesertic solonetzic complexes under different herbaceous communities with the participation of fodder plant Kochia prostrata (Caspian lowland)

The aim of the study was to research the relationship of chemical and micromorphological properties of soils with the growth ofKochia prostrata. The objects of study were the soils on natural pastures of the North-Western part of the Caspian lowland. It was laid 4 soil pits (soils – light solonetz, solonetzic chestnut) with the maximum penetration depth of the main mass of roots of the studied plants.K. prostratais a very plastic forage species that can grow on soils with a wide range of morphological properties, different salt content and their chemical composition. It is revealed that on the background of almost the same content of humus and high content of exchangeable magnesium micromorphological features represent the different degree of manifestation of primary pedogenic processes – humus accumulation, leaching of soluble salts, gypsum accumulation, carbonate enrichment, solonetzization. Despite the different content of exchangeable sodium, in all soils there are fresh clay or humus-clay illuvial coatings, indicating the manifestation of the modern eluvial-illuvial redistribution of fine matter (lessivage or illimerization).

STUDY OF COMBINED MAGNETIZED WATER AND SALINITY ON SOIL PERMEABILITY IN NORTH OF IRAN

The leaching of salts through facilitating the permeability process is very important for irrigation systems planning. The negative effect of soil compaction on plant growth is an integration of multidirectional influences, such as the reduction of aeration to the roots. This research was done at Babolsar city, Mazandaran province, Iran to investigate the effect of magnetized water and different irrigation water salinity treatments on cumulative and final infiltration rate and soil electrical conductivity. The experimental treatments include magnetized and non-magnetized irrigation water, different level of irrigation water salinity (0.58 dSm-1, 6.5 dSm-1, and 13 dSm-1) and variable soil texture (loamy-sand, loam, and clay). The factorial experiment was conducted with a complete randomized block design with three replications. Magnetized water was obtained by passing the water via a strong magnetic field installed on the irrigation pipeline. The results exposed that the effects of soil texture and magnetized irrigation water on the final infiltration rate and cumulative infiltration were significant (P

Evaluation of irrigation water salinity and leaching fraction on the water productivity for crops

In arid and semi-arid irrigated croplands, the excessive accumulation of soluble salts in the root zone is an extensive problem that seriously limits crop yield and water productivity (WP). To avoid affects the yield potential of crops, the application of extra irrigation for leaching of excessive salts from the root zone was required. Quantitative knowledge of effects of the irrigation water salinity and leaching fraction (LF) on the relative yield (RY) and the unit water productivity of crop evapotranspiration (UWPET) and the unit water productivity of irrigation water (UWPI) were becoming gradually important. This article provided theoretical models for estimating the UWPs (UWPET and UWPI) and optimizing leaching fraction according to irrigation water salinity. In the present study, eight levels of irrigation water salinity (ECw = 0.25, 0.50, 0.75, 1, 2, 3, 4, and 5 dS/m) and 39 levels of LF values ranging from 0.04 to 0.80 were set and tested to assessing their effects on the RY and UWPs for four typical crops (barley, bean, wheat, and maize) with different salt tolerance levels. Almost every curve determined between the UWPs and LFs for the four crops had an inflection point. It was indicated that the UWPET and UWPI could be maximized by optimizing the LF under different irrigation water salinities. Furthermore, the linear regression relationships were established to estimate the maximum values of UWPs and their corresponding optimal LFs for four crops by using the irrigation water salinity. Moreover, the theoretical models for estimating the UWPs were validated by data of wheat from previous literature, and the models could be suitable with acceptable relative errors when LFs ranging from 0.07 to 0.17. Keywords: irrigation water salinity, leaching fraction, salt-tolerant crop, salt stress, crop yield, water productivity DOI: 10.25165/j.ijabe.20201301.5047 Citation: Ning S R, Zhou B B, Wang Q J, Tao W H. Evaluation of irrigation water salinity and leaching fraction on the water productivity for crops. Int J Agric & Biol Eng, 2020; 13(1): 170–177.

Produced water's impact on soil properties: Remediation challenges and opportunities

AbstractThe choice of remediation of oil‐produced water (aka brine) spills depends on the severity of contamination, environmental factors, cost‐effectiveness, and relative efficiency of salt removal. The objective of this review is to summarize the current practices that are used to remediate brine spills or abandoned evaporation pits within the Bakken and Three Forks regions of the Williston Basin within the upper Great Plains. The most common current methods are “dig and haul” and the use of chemical amendments such as gypsum (CaSO4) or organic amendments (manure, straw, etc.) to promote soil flocculation and the downward leaching of salts out of the topsoil. These methods, however, can fail to achieve sustained remediation success in a cost‐effective and timely manner, making continued research into alternative methods necessary. The use of electrokinetics, crystallization inhibitors, wicking materials, and plant‐growth promoting rhizobacteria hold promise for in‐situ cleanup of contaminated sites.

Judging causes of soil degradation and remedial measures for reclamation in Kaithal district of Haryana state

Soil degradation is a point of evolution which leads to a reduction of resource potential. About 7.40 m ha arable lands globally turn to degraded lands as a result of climate change and deforestation. The problem of soil degradation has been ever since cultivation of soils started because of increasing population of India at the rate of about 1.8% requiring marginal areas to be brought under the plough to meet the growing food demand. The present study was conducted in Kaithal district in the year 2018-19. The study revealed that ‘Excessive use of chemical fertilizers’ (88.33%) followed by ‘non- judicious use of insecticides/pesticides’ (85.83%), ‘less application of organic manure’ (85.00%), ‘deforestation (78.33%), and ‘over uplifting of ground water’ (75.83%) were found as most important causes of soil degradation. The most important remedial action for problematic soil were found as ‘land for equal distribution of resources/irrigation’ (90.83%) followed by ‘application of Gypsum for sodic and saline soil’ (85.83%), ‘introduction of legumes in cropping system’ (80.00%), ‘recharge of ground water during rainy season’ (78.33%), ‘crop residue incorporation by happy seeder’ (77.50%), ‘application of green manuring/ organic manure’ (75.00%) and ‘leaching of salts in saline soil’ (72.50%). Soil conservation is important for the future use and future generation. The study would be helpful in soils conservation which may otherwise cause damage to plant growth which in turn may adversely affect yield and there by food security also.

Relationship between soil and groundwater salinity in the Western Canada Sedimentary Basin.

Saturated soil paste extracts indicate soluble ions in soil pore water that are available to vegetation. As such, they are thought to accurately describe the relationship between soil and groundwater salinity. To test this assumption, soil and groundwater samples were collected from 575 monitoring wells in saline regions of the Western Canadian Sedimentary Basin (WCSB). Samples were analyzed for electrical conductivity (EC) and Cl-, Na+, Ca2+, Mg2+, K+, SO42-, and HCO- 3 content. We compared groundwater ionic concentrations to paste extracts derived from matching soils, finding that differences from in situ soil porosity cause saturated pastes to underestimate groundwater salinity. Therefore, we provide pedotransfer functions for accurately calculating groundwater quality from soil data. In addition, we discuss the effects of porosity and soil composition on the saturated paste method, as measured through hydraulic conductivity, saturation percent, and sample lithology. Groundwater salinity may also influence further leaching of salts from soil. As produced water (NaCl brine) spills are common across the sulfate-rich soils of the WCSB, we considered the effects of NaCl on leaching of other ions, finding that influx of Na+ into groundwater is associated with increased sulfate leaching from soil. Therefore, considering the secondary effects of produced water on groundwater quality is essential to spill management.