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Sample records for saline soils

  1. Saline waters and soil quality

    Directory of Open Access Journals (Sweden)

    Carmelo Dazzi

    Full Text Available The processes of secondary salinization due to anthropic actions are considered one of the most important environmental emergencies owing to their level of dangerousness. The soils of the dry areas of the Mediterranean basin are particularly prone to these processes. In such environments, it is imperative to resort to irrigation that allow for the reduction of risks due to soil moisture deficit and for the stabilization of yields. Frequently, saline waters are used that cause a lowering of the soil quality. If on one hand the presence of salts can benefit the soils mainly improving soil structure, on the other high levels of salts produce negative effects on soils and crops.When sodium prevails problems of soil quality can rise such as structure degradation, low hydraulic conductivity, soil sealing. The processes of secondary soil salinization due to the use of saline waters for irrigation are particularly evident in our Country among others. In Italy, saline soils are mainly distributed in long strips of the coastal belt of the Tyrrhenian sea and Adriatic sea, in the coastal belt of Apulia, Basilicata and Sardinia and in wide areas of Sicily. It is not possible to suggest general actions to combat soil salinization because we must take into consideration that in the relationship soil-water two different quality concept interact: one linked to the soils, the other to the waters.

  2. Saline waters and soil quality

    Directory of Open Access Journals (Sweden)

    Carmelo Dazzi

    2011-02-01

    Full Text Available The processes of secondary salinization due to anthropic actions are considered one of the most important environmental emergencies owing to their level of dangerousness. The soils of the dry areas of the Mediterranean basin are particularly prone to these processes. In such environments, it is imperative to resort to irrigation that allow for the reduction of risks due to soil moisture deficit and for the stabilization of yields. Frequently, saline waters are used that cause a lowering of the soil quality. If on one hand the presence of salts can benefit the soils mainly improving soil structure, on the other high levels of salts produce negative effects on soils and crops.When sodium prevails problems of soil quality can rise such as structure degradation, low hydraulic conductivity, soil sealing. The processes of secondary soil salinization due to the use of saline waters for irrigation are particularly evident in our Country among others. In Italy, saline soils are mainly distributed in long strips of the coastal belt of the Tyrrhenian sea and Adriatic sea, in the coastal belt of Apulia, Basilicata and Sardinia and in wide areas of Sicily. It is not possible to suggest general actions to combat soil salinization because we must take into consideration that in the relationship soil-water two different quality concept interact: one linked to the soils, the other to the waters.

  3. Stochastic modeling of soil salinity

    NARCIS (Netherlands)

    Suweis, S.; Rinaldo, A.; Zee, van der S.E.A.T.M.; Daly, E.; Maritan, A.

    2010-01-01

    A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and

  4. Stochastic Modeling of Soil Salinity

    Science.gov (United States)

    Suweis, Samir; Rinaldo, Andrea; van der Zee, Sjoerd E. A. T. M.; Maritan, Amos; Porporato, Amilcare

    2010-05-01

    Large areas of cultivated land worldwide are affected by soil salinity. Estimates report that 10% of arable land in over 100 countries, and nine million km2 are salt affected, especially in arid and semi-arid regions. High salinity causes both ion specific and osmotic stress effects, with important consequences for plant production and quality. Salt accumulation in the root zone may be due to natural factors (primary salinization) or due to irrigation (secondary salinization). Simple (e.g., vertically averaged over the soil depth) coupled soil moisture and salt balance equations have been used in the past. Despite their approximations, these models have the advantage of parsimony, thus allowing a direct analysis of the interplay of the main processes. They also provide the ideal starting point to include external, random hydro-climatic fluctuations in the analysis of long-term salinization trends. We propose a minimalist stochastic model of primary soil salinity, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equation to a stochastic differential equation driven by multiplicative Poisson noise. The novel analytical solutions provide insight on the interplay of the main soil, plant and climate parameters responsible for long-term soil salinization. In fact, soil salinity statistics are obtained as a function of climate, soil and vegetation parameters. These, in turn, can be combined with soil moisture statistics to obtain a full characterization of soil salt concentrations and the ensuing risk of primary salinization. In particular, the solutions show the existence of two quite distinct regimes, the first one where the mean salt mass remains nearly constant with increasing rainfall frequency, and the

  5. Stochastic Modeling of Soil Salinity

    CERN Document Server

    Suweis, S; Van der Zee, S E A T M; Daly, E; Maritan, A; Porporato, A; 10.1029/2010GL042495

    2012-01-01

    A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equation to a single stochastic differential equation driven by multiplicative Poisson noise. The novel analytical solutions provide insight on the interplay of the main soil, plant and climate parameters responsible for long-term soil salinization. In particular, they show the existence of two distinct regimes, one where the mean salt mass remains nearly constant (or decreases) with increasing rainfall frequency, and another where mean salt content increases markedly with increasing rainfall frequency. As a result, relatively small reductions of rainfall in drier climates may entail dramatic shifts in long-term soil salinization trend...

  6. Stochastic modeling of soil salinity

    Science.gov (United States)

    Suweis, S.; Porporato, A. M.; Daly, E.; van der Zee, S.; Maritan, A.; Rinaldo, A.

    2010-12-01

    A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The equations for the probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equations to a single stochastic differential equation (generalized Langevin equation) driven by multiplicative Poisson noise. Generalized Langevin equations with multiplicative white Poisson noise pose the usual Ito (I) or Stratonovich (S) prescription dilemma. Different interpretations lead to different results and then choosing between the I and S prescriptions is crucial to describe correctly the dynamics of the model systems. We show how this choice can be determined by physical information about the timescales involved in the process. We also show that when the multiplicative noise is at most linear in the random variable one prescription can be made equivalent to the other by a suitable transformation in the jump probability distribution. We then apply these results to the generalized Langevin equation that drives the salt mass dynamics. The stationary analytical solutions for the probability density functions of salt mass and concentration provide insight on the interplay of the main soil, plant and climate parameters responsible for long term soil salinization. In particular, they show the existence of two distinct regimes, one where the mean salt mass remains nearly constant (or decreases) with increasing rainfall frequency, and another where mean salt content increases markedly with increasing rainfall frequency. As a result, relatively small reductions of rainfall in drier climates may entail dramatic shifts in longterm soil salinization trends, with significant consequences, e.g. for climate change impacts on rain fed agriculture.

  7. Managing the Economics of Soil Salinity

    OpenAIRE

    Hadrich, Joleen C.

    2011-01-01

    Saline soils result in decreased crop growth and yield with the potential for losing productive farm land. Enterprise budget analysis was extended to include the fixed costs of installing tile drainage to manage soil salinity in the Red River Valley of North Dakota for corn, soybeans, wheat, sugar beets, and barley. Installing tile drainage to manage soil salinity decreased per acre crop profitability from 19-49% due to the large upfront capital investment of tile drainage. These losses can b...

  8. SOIL SALINITY MAPPING USING MULTITEMPORAL LANDSAT DATA

    Directory of Open Access Journals (Sweden)

    A. Azabdaftari

    2016-06-01

    Full Text Available Soil salinity is one of the most important problems affecting many areas of the world. Saline soils present in agricultural areas reduce the annual yields of most crops. This research deals with the soil salinity mapping of Seyhan plate of Adana district in Turkey from the years 2009 to 2010, using remote sensing technology. In the analysis, multitemporal data acquired from LANDSAT 7-ETM+ satellite in four different dates (19 April 2009, 12 October 2009, 21 March 2010, 31 October 2010 are used. As a first step, preprocessing of Landsat images is applied. Several salinity indices such as NDSI (Normalized Difference Salinity Index, BI (Brightness Index and SI (Salinity Index are used besides some vegetation indices such as NDVI (Normalized Difference Vegetation Index, RVI (Ratio Vegetation Index, SAVI (Soil Adjusted Vegetation Index and EVI (Enhamced Vegetation Index for the soil salinity mapping of the study area. The field’s electrical conductivity (EC measurements done in 2009 and 2010, are used as a ground truth data for the correlation analysis with the original band values and different index image bands values. In the correlation analysis, two regression models, the simple linear regression (SLR and multiple linear regression (MLR are considered. According to the highest correlation obtained, the 21st March, 2010 dataset is chosen for production of the soil salinity map in the area. Finally, the efficiency of the remote sensing technology in the soil salinity mapping is outlined.

  9. Soil salinity prediction using electromagnetic induction method in gypsiferous soil

    Science.gov (United States)

    Bouksila, Fethi; Persson, Magnus; Bahri, Akiça; Berndtsson, Ronny; Ben Slimane, Abir

    2017-04-01

    In arid and semiarid regions, secondary soil salinization is considered a main danger to the sustainability of irrigated land and agricultural production. Thus, accurate and rapid estimation of soil salinity should be readily available to farmers during crop development to increase productivity and to contribute to sustainable land planning aimed at mitigating soil degradation. Measurement of electrical conductivity in saturated paste extracts (ECe) is a standard method for which other salinity estimation methods are referenced. In the present study, we investigated the possibilities to use the EM38 to predict field ECe in a saline gypsiferous soil of the Saharian-climate Fatnassa oasis (Tunisia) under shallow and saline groundwater. On the 114 ha oasis, an experimental network system of 27 agricultural plots was chosen for monitoring soil properties (ECa-EM38, soil particle size, gypsum content, soil moisture, and ECe) and groundwater (depth, Dgw, electrical conductivity, and ECgw). Samples were taken during 4 years (2001 to 2004) at experimental plots and soil profiles were sampled at 0.2 m depth intervals to 1.2 m for physical and chemical analysis. The results showed that significant lnECe-EM relationships could be developed. However, results also indicated that for better accuracy of soil salinity prediction using the EM38, it is advisable to perform calibrations for each measurement period.

  10. Investigation of soil salinity to distinguish boundary line between ...

    African Journals Online (AJOL)

    Gradual drying of Urmia Lake has left vast saline areas all around it, increasing the risk of salinization of agricultural lands next to the Lake. The current research was aimed to predict soil salinity and distinguish the boundary line between saline and agricultural lands by taking in to account the spatial variability of soil salinity ...

  11. Climate change and soil salinity: The case of coastal Bangladesh.

    Science.gov (United States)

    Dasgupta, Susmita; Hossain, Md Moqbul; Huq, Mainul; Wheeler, David

    2015-12-01

    This paper estimates location-specific soil salinity in coastal Bangladesh for 2050. The analysis was conducted in two stages: First, changes in soil salinity for the period 2001-2009 were assessed using information recorded at 41 soil monitoring stations by the Soil Research Development Institute. Using these data, a spatial econometric model was estimated linking soil salinity with the salinity of nearby rivers, land elevation, temperature, and rainfall. Second, future soil salinity for 69 coastal sub-districts was projected from climate-induced changes in river salinity and projections of rainfall and temperature based on time trends for 20 Bangladesh Meteorological Department weather stations in the coastal region. The findings indicate that climate change poses a major soil salinization risk in coastal Bangladesh. Across 41 monitoring stations, the annual median projected change in soil salinity is 39 % by 2050. Above the median, 25 % of all stations have projected changes of 51 % or higher.

  12. How mangroves salinize the soil

    NARCIS (Netherlands)

    C.J. van Duijn (Hans); G. Galiano; J.H. Knight; M.A. Peletier (Mark)

    1997-01-01

    textabstractA transient one-dimensional model of the vertical movement of water and salt in the mangrove root zone is investigated. This is an extension of a previous steady state model which assumed that the ability of the mangrove roots to take up water is uniformly distributed throughout the soil

  13. Influence of salinity and water content on soil microorganisms

    OpenAIRE

    Nan Yan; Petra Marschner; Wenhong Cao; Changqing Zuo; Wei Qin

    2015-01-01

    Salinization is one of the most serious land degradation problems facing world. Salinity results in poor plant growth and low soil microbial activity due to osmotic stress and toxic ions. Soil microorganisms play a pivotal role in soils through mineralization of organic matter into plant available nutrients. Therefore it is important to maintain high microbial activity in soils. Salinity tolerant soil microbes counteract osmotic stress by synthesizing osmolytes which allows them to maintain t...

  14. Spatial variability of soil salinity in coastal saline soil at different scales in the Yellow River Delta, China.

    Science.gov (United States)

    Wang, Zhuoran; Zhao, Gengxing; Gao, Mingxiu; Chang, Chunyan

    2017-02-01

    The objectives of this study were to explore the spatial variability of soil salinity in coastal saline soil at macro, meso and micro scales in the Yellow River delta, China. Soil electrical conductivities (ECs) were measured at 0-15, 15-30, 30-45 and 45-60 cm soil depths at 49 sampling sites during November 9 to 11, 2013. Soil salinity was converted from soil ECs based on laboratory analyses. Our results indicated that at the macro scale, soil salinity was high with strong variability in each soil layer, and the content increased and the variability weakened with increasing soil depth. From east to west in the region, the farther away from the sea, the lower the soil salinity was. The degrees of soil salinization in three deeper soil layers are 1.14, 1.24 and 1.40 times higher than that in the surface soil. At the meso scale, the sequence of soil salinity in different topographies, soil texture and vegetation decreased, respectively, as follows: depression >flatland >hillock >batture; sandy loam >light loam >medium loam >heavy loam >clay; bare land >suaeda salsa >reed >cogongrass >cotton >paddy >winter wheat. At the micro scale, soil salinity changed with elevation in natural micro-topography and with anthropogenic activities in cultivated land. As the study area narrowed down to different scales, the spatial variability of soil salinity weakened gradually in cultivated land and salt wasteland except the bare land.

  15. Soil Salinity: Effect on Vegetable Crop Growth. Management Practices to Prevent and Mitigate Soil Salinization

    Directory of Open Access Journals (Sweden)

    Rui Manuel Almeida Machado

    2017-05-01

    Full Text Available Salinity is a major problem affecting crop production all over the world: 20% of cultivated land in the world, and 33% of irrigated land, are salt-affected and degraded. This process can be accentuated by climate change, excessive use of groundwater (mainly if close to the sea, increasing use of low-quality water in irrigation, and massive introduction of irrigation associated with intensive farming. Excessive soil salinity reduces the productivity of many agricultural crops, including most vegetables, which are particularly sensitive throughout the ontogeny of the plant. The salinity threshold (ECt of the majority of vegetable crops is low (ranging from 1 to 2.5 dS m−1 in saturated soil extracts and vegetable salt tolerance decreases when saline water is used for irrigation. The objective of this review is to discuss the effects of salinity on vegetable growth and how management practices (irrigation, drainage, and fertilization can prevent soil and water salinization and mitigate the adverse effects of salinity.

  16. Sustainable management of coastal saline soils in the Saloum river ...

    African Journals Online (AJOL)

    Sustainable management of coastal saline soils in the Saloum river Basin, Senegal. ... Salinization of soils is one of the major environmental problems facing the world. Frequent tidal intrusions and continuous ... The vertical pattern occurs within soil profiles and is closely linked to soil texture and groundwater dynamic.

  17. Partnership for adapting Vulnerable Populations to Soil Salinization ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Soil salinization affects nearly all regions of Sénégal. Nearly a million hectares are affected by salinization and acidification. It is only in the last few years that researchers have understood the relation between soil salinization and climate change. This project aims to increase the capacity of rural communities, ...

  18. Investigation of Soil Salinity to Distinguish Boundary Line between ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: Gradual drying of Urmia Lake has left vast saline areas all around it, increasing the risk of salinization of agricultural lands next to the Lake. The current research was aimed to predict soil salinity and distinguish the boundary line between saline and agricultural lands by taking in to account the spatial variability ...

  19. Assessing the impact of soil salinity on manganese distribution in sierozem soils

    Science.gov (United States)

    Plant availability of heavy metals from soil depends on factors such as soil type, organic matter, base saturation, texture, and salinity. Plant availability of mobile manganese (Mn) was accessed from various horizons of non-saline, medium saline, and highly saline sieriozem soils and a pasture. Man...

  20. Influence of salinity and water content on soil microorganisms

    Directory of Open Access Journals (Sweden)

    Nan Yan

    2015-12-01

    Full Text Available Salinization is one of the most serious land degradation problems facing world. Salinity results in poor plant growth and low soil microbial activity due to osmotic stress and toxic ions. Soil microorganisms play a pivotal role in soils through mineralization of organic matter into plant available nutrients. Therefore it is important to maintain high microbial activity in soils. Salinity tolerant soil microbes counteract osmotic stress by synthesizing osmolytes which allows them to maintain their cell turgor and metabolism. Osmotic potential is a function of the salt concentration in the soil solution and therefore affected by both salinity (measured as electrical conductivity at a certain water content and soil water content. Soil salinity and water content vary in time and space. Understanding the effect of changes in salinity and water content on soil microorganisms is important for crop production, sustainable land use and rehabilitation of saline soils. In this review, the effects of soil salinity and water content on microbes are discussed to guide future research into management of saline soils.

  1. Effects of Soil Salinity on Sucrose Metabolism in Cotton Fiber.

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    Jun Peng

    Full Text Available Cotton (Gosspium hirsutum L. is classified as a salt tolerant crop. However, its yield and fiber quality are negatively affected by soil salinity. Studies on the enzymatic differences in sucrose metabolism under different soil salinity levels are lacking. Therefore, field experiments, using two cotton cultivars, CCRI-79 (salt-tolerant and Simian 3 (salt-sensitive, were conducted in 2013 and 2014 at three different salinity levels (1.15 dS m-1 [low soil salinity], 6.00 dS m-1 [medium soil salinity], and 11.46 dS m-1 [high soil salinity]. The objective was to elucidate the effects of soil salinity on sucrose content and the activity of key enzymes that are related to sucrose metabolism in cotton fiber. Results showed that as the soil salinity increased, cellulose content, sucrose content, and sucrose transformation rate declined; the decreases in cellulose content and sucrose transformation rate caused by the increase in soil salinity were more in Simian 3 than those in CCRI-79. With increase in soil salinity, activities of sucrose metabolism enzymes sucrose phophate synthase (SPS, acidic invertase, and alkaline invertase were decreased, whereas sucrose synthase (SuSy activity increased. However, the changes displayed in the SuSy and SPS activities in response to increase in soil salinity were different and the differences were large between the two cotton cultivars. These results illustrated that suppressed cellulose synthesis and sucrose metabolism under high soil salinity were mainly due to the change in SPS, SuSy, and invertase activities, and the difference in cellulose synthesis and sucrose metabolism in fiber for the two cotton cultivars in response to soil salinity was determined mainly by both SuSy and SPS activities.

  2. Influence of salinity on soil chemical properties and surrounding ...

    African Journals Online (AJOL)

    Akomolafe Gbenga

    2013-11-14

    Nov 14, 2013 ... samples were collected randomly from the salt mining site and 10 m away from the site (control) at 5, ... Salt-affected soils, as they are called, are either saline or sodic. Saline soils refer to soils with electrical conductivity above 4. dS/m and usually ... Brock, 2001; USDA, Natural Resources Conservation.

  3. Soil salinity detection from satellite image analysis: an integrated approach of salinity indices and field data.

    Science.gov (United States)

    Morshed, Md Manjur; Islam, Md Tazmul; Jamil, Raihan

    2016-02-01

    This paper attempts to detect soil salinity from satellite image analysis using remote sensing and geographic information system. Salinity intrusion is a common problem for the coastal regions of the world. Traditional salinity detection techniques by field survey and sampling are time-consuming and expensive. Remote sensing and geographic information system offer economic and efficient salinity detection, monitoring, and mapping. To predict soil salinity, an integrated approach of salinity indices and field data was used to develop a multiple regression equation. The correlations between different indices and field data of soil salinity were calculated to find out the highly correlated indices. The best regression model was selected considering the high R (2) value, low P value, and low Akaike's Information Criterion. About 20% variation was observed between the field data and predicted EC from the satellite image analysis. The precision of this salinity detection technique depends on the accuracy and uniform distribution of field data.

  4. Measurement of salinity and electrical conductivity of some soil ...

    African Journals Online (AJOL)

    The salinity and electrical conductivity of some selected soil samples from Uruan Local government area of Akwa Ibom state of the Federal Republic of Nigeria were measured. The results show that an increase in salinity gives rise to an increase in electrical conductivity. The salinities of the area under study falls within the ...

  5. Soil salinity study in Northern Great Plains sodium affected soil

    Science.gov (United States)

    Kharel, Tulsi P.

    Climate and land-use changes when combined with the marine sediments that underlay portions of the Northern Great Plains have increased the salinization and sodification risks. The objectives of this dissertation were to compare three chemical amendments (calcium chloride, sulfuric acid and gypsum) remediation strategies on water permeability and sodium (Na) transport in undisturbed soil columns and to develop a remote sensing technique to characterize salinization in South Dakota soils. Forty-eight undisturbed soil columns (30 cm x 15 cm) collected from White Lake, Redfield, and Pierpont were used to assess the chemical remediation strategies. In this study the experimental design was a completely randomized design and each treatment was replicated four times. Following the application of chemical remediation strategies, 45.2 cm of water was leached through these columns. The leachate was separated into 120- ml increments and analyzed for Na and electrical conductivity (EC). Sulfuric acid increased Na leaching, whereas gypsum and CaCl2 increased water permeability. Our results further indicate that to maintain effective water permeability, ratio between soil EC and sodium absorption ratio (SAR) should be considered. In the second study, soil samples from 0-15 cm depth in 62 x 62 m grid spacing were taken from the South Dakota Pierpont (65 ha) and Redfield (17 ha) sites. Saturated paste EC was measured on each soil sample. At each sampling points reflectance and derived indices (Landsat 5, 7, 8 images), elevation, slope and aspect (LiDAR) were extracted. Regression models based on multiple linear regression, classification and regression tree, cubist, and random forest techniques were developed and their ability to predict soil EC were compared. Results showed that: 1) Random forest method was found to be the most effective method because of its ability to capture spatially correlated variation, 2) the short wave infrared (1.5 -2.29 mum) and near infrared (0

  6. Soil classification groups to quantify primary salinity, sodicity and ...

    African Journals Online (AJOL)

    This study aimed to quantify the primary salinity, sodicity and alkalinity of South African soils based on soil classification groups and rainfall classes, by using available analysed data. The 73 soil forms used by the Soil Classification Working Group were organised into 11 groups based on the occurrence of specific horizons.

  7. Towards decadal soil salinity mapping using Landsat time series data

    Science.gov (United States)

    Fan, Xingwang; Weng, Yongling; Tao, Jinmei

    2016-10-01

    Salinization is one of the major soil problems around the world. However, decadal variation in soil salinization has not yet been extensively reported. This study exploited thirty years (1985-2015) of Landsat sensor data, including Landsat-4/5 TM (Thematic Mapper), Landsat-7 ETM+ (Enhanced Thematic Mapper Plus) and Landsat-8 OLI (Operational Land Imager), for monitoring soil salinity of the Yellow River Delta, China. The data were initially corrected for atmospheric effects, and then matched the spectral bands of EO-1 (Earth Observing One) ALI (Advanced Land Imager). Subsequently, soil salinity maps were derived with a previously developed PLSR (Partial Least Square Regression) model. On intra-annual scale, the retrievals showed that soil salinity increased in February, stabilized in March, and decreased in April. On inter-annual scale, soil salinity decreased within 1985-2000 (-0.74 g kg-1/10a, p salinity retrieval, and further the understanding of soil salinization development over the Yellow River Delta.

  8. Impacts of Salinity on Soil Hydraulic Properties and Evaporation Fluxes

    Science.gov (United States)

    Fierro, V.; Cristi Matte, F.; Suarez, F. I.; Munoz, J. F.

    2014-12-01

    Saline soils are common in arid zones, where evaporation from shallow groundwater is generally the main component of the water balance. Thus, to correctly manage water resources in these zones, it is important to quantify the evaporation fluxes. Evaporation from saline soils is a complex process that couples the movement of salts, heat, liquid water and water vapor, and strongly depends on the soil water content. Precipitation/dissolution reactions can change the soil structure and alter flow paths, modifying evaporation fluxes. We utilized the HYDRUS-1D model to investigate the effects of salinity on soil hydraulic properties and evaporation fluxes. HYDRUS-1D simulates the transport of liquid water, water vapor, and heat, and can incorporate precipitation/dissolution reactions of the major ions. To run the model, we determined the water retention curve for a soil with different salinities; and we used meteorological forcing from an experimental site from the Atacama Desert. It was found that higher sodium adsorption ratios in the soil increase the soil water retention capacity. Also, it was found that evaporation fluxes increase salts concentration near the soil surface, changing the soil's water retention capacity in that zone. Finally, movement of salts causes differences in evaporation fluxes. It is thus necessary to incorporate salt precipitation/dissolution reactions and its effects on the water retention curve to correctly simulate evaporation in saline soils

  9. Physical and chemical properties of long-term salinized soils

    Directory of Open Access Journals (Sweden)

    Celestino Ruggiero

    2011-02-01

    Full Text Available In some areas, particularly in the Mediterranean regions, saline water is a source of water for crop irrigation. Consequently during the time, the use of this water may cause significant modifications of the soil physic-chemical properties and plant toxicity. The purpose of this investigation was to assess the variation of soil stability index and of ECe, ESP, pH, exchangeable potassium, bulk density, soil hydraulic conductivity and water retention curve (h(θ, for a clay sandy soil, which was irrigated over 12 years with saline water. The soil stability index was evaluated by 2 methods: after wetting the sample (Water Stability Index = WSI and without the pre-wetting step (Water Stability Dry Index = WSDI. The measures have been taken at three depths along the soil profile: 0-0.30, 0.30-0.60 and 0.60-0.90 m. The saline water was obtained by adding commercial sea salt to the irrigation water with the result of a final concentrations of 0.25 (2.5 g l-1, 0.5 (5 g l-1 and 1% (10 g l-1. A non-salinized control was also included. The increasing salinity of the irrigation water increased at all the depths ECe, ESP and pH, while exchangeable potassium decreased. Assessment of soil aggregates stability without samples pre-wetting (WSDI allowed us to better discriminate among the different samples examined. Aggregate stability for each of the soil layers decreased at increasing salinity of the irrigation water. Long term salinization affected the aggregate stability of the deepest layers. The soil hydraulic conductivity decreased also, while bulk density increased. The shape of the soil water retention curve was also affected by salinity. In the salinized plots less water is relaxed within -150 ÷ -12 cm ψ range. The available water was reduced at increasing salinity. Irrigation with saline water on clay-sandy soils increases ECe, pH and ESP, all of which negatively affect the soil aggregate stability. Damage to the soil structure remarkably reduces the

  10. Physical and chemical properties of long-term salinized soils

    Directory of Open Access Journals (Sweden)

    Celestino Ruggiero

    2006-06-01

    Full Text Available In some areas, particularly in the Mediterranean regions, saline water is a source of water for crop irrigation. Consequently during the time, the use of this water may cause significant modifications of the soil physic-chemical properties and plant toxicity. The purpose of this investigation was to assess the variation of soil stability index and of ECe, ESP, pH, exchangeable potassium, bulk density, soil hydraulic conductivity and water retention curve (h(θ, for a clay sandy soil, which was irrigated over 12 years with saline water. The soil stability index was evaluated by 2 methods: after wetting the sample (Water Stability Index = WSI and without the pre-wetting step (Water Stability Dry Index = WSDI. The measures have been taken at three depths along the soil profile: 0-0.30, 0.30-0.60 and 0.60-0.90 m. The saline water was obtained by adding commercial sea salt to the irrigation water with the result of a final concentrations of 0.25 (2.5 g l-1, 0.5 (5 g l-1 and 1% (10 g l-1. A non-salinized control was also included. The increasing salinity of the irrigation water increased at all the depths ECe, ESP and pH, while exchangeable potassium decreased. Assessment of soil aggregates stability without samples pre-wetting (WSDI allowed us to better discriminate among the different samples examined. Aggregate stability for each of the soil layers decreased at increasing salinity of the irrigation water. Long term salinization affected the aggregate stability of the deepest layers. The soil hydraulic conductivity decreased also, while bulk density increased. The shape of the soil water retention curve was also affected by salinity. In the salinized plots less water is relaxed within -150 ÷ -12 cm ψ range. The available water was reduced at increasing salinity. Irrigation with saline water on clay-sandy soils increases ECe, pH and ESP, all of which negatively affect the soil aggregate stability. Damage to the soil structure remarkably reduces the

  11. Reclamation of Sodic-Saline Soils. Barley Crop Response

    Directory of Open Access Journals (Sweden)

    Giovanna Cucci

    2008-12-01

    Full Text Available The research was aimed at assessing the salinity and sodicity effects of two soil types submitted to correction on barley crop. The two soils, contained in cylindrical pots (0.40 m in size and 0.60 m h supplied with a bottom valve for the collection of drainage water and located under shed to prevent the leaching action of rainfall, were clay-textured and saline and sodic-saline at barley seeding, as they had been cultivated for 4 consecutive years with different herbaceous species irrigated with 9 types of brackish water. In 2002-2003 the 2 salinized and sodium-affected soils (ECe and ESP ranging respectively from 5.84-20.27 dSm-1 to 2.83-11.19%, submitted to correction, were cultivated with barley cv Micuccio, and irrigated with fresh water (ECw = 0.5 dS m-1 and SAR = 0.45 whenever 30% of the maximum soil available moisture was lost by evapotranspiration. Barley was shown to be a salt-tolerant species and did not experience any salt stress when grown in soils with an initial ECe up to 11 dS m-1. When it was grown in more saline soils (initial ECe of about 20 dS m-1, despite the correction, it showed a reduction in shoot biomass and kernel yield by 26% and 36% respectively, as compared to less saline soils.

  12. Saline soils spectral library as a tool for digital soil mapping

    Science.gov (United States)

    Bas, María Victoria; Meléndez-Pastor, Ignacio; Navarro-Pedreño, José; Gómez, Ignacio; Mataix-Solera, Jorge; Hernández, Encarni

    2013-04-01

    Soil information is needed at regional to global scales for proper land management. Soil scientist has been historically interested in mapping soil classes and properties to represent and explore the spatial distribution of soil characteristics. Fortunately, soil mapping came into the digital era decades ago, enabling the dissemination of computationally intensive techniques (e.g., geostatistics). Digital soil mapping is moving forward in recent decades. Digital soil mapping has evolved from "traditional" studies that employed a set of soils to build soil maps, to more recent approaches that exploit the increasing computing facilities to combine soil databases with ancillary data such as digital elevation models, remote sensing imagery and proximal sensing datasets. The inclusion of VNIR spectroscopy in digital soil mapping approaches is an outstanding research field. VNIR spectroscopy has largely been employed to quantify soil properties with proximal sensor and remote sensor (i.e., imaging spectroscopy). One of the traditional problems in soil mapping is the time needed to compile a soil database large enough to allow for mapping with robustness. Therefore there is a growing interest in using the less time consuming, immutability of the sample and increasing accuracy of soil spectroscopy to obtain accurate enough soil maps but with lower data requirements. This research trend is particularly interesting for the study of highly dynamic soil processes for which is necessary to know the spatial and temporal changes of certain properties for a correct soil assessment. The objective of this work was the study of soil salinity which is a dynamic property responding to seasonal (i.e., vertical upwelling) and inter-annual (i.e., salinization) changes. Soil salinity is a major constraint for agriculture by limiting or excluding certain crops. Thus, a continuous monitoring of soil salinity is needed to select the most suitable crops and to prevent future salinization

  13. Effect of salinity on the bioremediation of petroleum hydrocarbons in a saline-alkaline soil.

    Science.gov (United States)

    Qin, X; Tang, J C; Li, D S; Zhang, Q M

    2012-09-01

     The aim of this paper is to check the effect of salinity on the bioremediation process of petroleum hydrocarbons in the saline-alkaline soil.  In this study, soil salinity was adjusted to different levels by water leaching method and the bioremediation process was conducted for 28 days. Soil pH increased after leaching and decreased during bioremediation process. At initial time, moderate salinity enhanced the biodegradation and addition of microbial consortium was not effective in enhancing degradation rate of petroleum hydrocarbons. At day of 28 days, higher degradation rate was found in treatments with more leaching times with a maximum value of 42·36%. Dehydrogenase activity increased with the progress of bioremediation and positive correlation was found between dehydrogenase activity and degradation rate of petroleum hydrocarbons. Denaturing gradient gel electrophoresis analysis result showed decreased microbial community diversity with increased salt content.  The result suggested that salinity had great impact on bioremediation, and leaching and addition of inoculated consortium were effective in enhancing biodegradation of petroleum hydrocarbons in the saline-alkaline soil.  The result of this study is important for understanding the bioremediation process of petroleum in contaminated soil. New remediation method of petroleum contaminated soil can be developed based on this study. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

  14. Soil Chemistry Factors Confounding Crop Salinity Tolerance—A Review

    Directory of Open Access Journals (Sweden)

    Pichu Rengasamy

    2016-10-01

    Full Text Available The yield response of various crops to salinity under field conditions is affected by soil processes and environmental conditions. The composition of dissolved ions depend on soil chemical processes such as cation or anion exchange, oxidation-reduction reactions, ion adsorption, chemical speciation, complex formation, mineral weathering, solubility, and precipitation. The nature of cations and anions determine soil pH, which in turn affects crop growth. While the ionic composition of soil solution determine the osmotic and ion specific effects on crops, the exchangeable ions indirectly affect the crop growth by influencing soil strength, water and air movement, waterlogging, and soil crusting. This review mainly focuses on the soil chemistry processes that frustrate crop salinity tolerance which partly explain the poor results under field conditions of salt tolerant genotypes selected in the laboratory.

  15. Predictive spatial modelling for mapping soil salinity at continental scale

    Science.gov (United States)

    Bui, Elisabeth; Wilford, John; de Caritat, Patrice

    2017-04-01

    Soil salinity is a serious limitation to agriculture and one of the main causes of land degradation. Soil is considered saline if its electrical conductivity (EC) is > 4 dS/m. Maps of saline soil distribution are essential for appropriate land development. Previous attempts to map soil salinity over extensive areas have relied on satellite imagery, aerial electromagnetic (EM) and/or proximally sensed EM data; other environmental (climate, topographic, geologic or soil) datasets are generally not used. Having successfully modelled and mapped calcium carbonate distribution over the 0-80 cm depth in Australian soils using machine learning with point samples from the National Geochemical Survey of Australia (NGSA), we took a similar approach to map soil salinity at 90-m resolution over the continent. The input data were the EC1:5 measurements on the learning software 'Cubist' (www.rulequest.com) was used as the inference engine for the modelling, a 90:10 training:test set data split was used to validate results, and 100 randomly sampled trees were built using the training data. The results were good with an average internal correlation (r) of 0.88 between predicted and measured logEC1:5 (training data), an average external correlation of 0.48 (test subset), and a Lin's concordance correlation coefficient (which evaluates the 1:1 fit) of 0.61. Therefore, the rules derived were mapped and the mean prediction for each 90-m pixel was used for the final logEC1:5 map. This is the most detailed picture of soil salinity over Australia since the 2001 National Land and Water Resources Audit and is generally consistent with it. Our map will be useful as a baseline salinity map circa 2008, when the NGSA samples were collected, for future State of the Environment reports.

  16. Assessment of Satellite Images for Soil Salinity Studies

    Directory of Open Access Journals (Sweden)

    S.H. Sanaeinejad

    2012-04-01

    Full Text Available Soil salinity is one of the main environmental problems affecting extensive area in the world. There are some problems with traditional data collection methods for soil studies. Using the new methods and techniques such as remote sensing could overcome most of these problems. However using these data in areas with uncommon usages needed some researches to find the best calibration between the data and real situations in soil. This research was carried out using Landsat satellite images in Neyshabour area, North East of Iran. In order to prepare suitable learning samples for the image processing in this study, 300 locations were randomly selected in the area, among which 273 locations were finally selected as suitable surface soil samples. All samples were moved to laboratory and their electrical conductivity was measured. Six reflective bands of ETM+ satellite images taken from the study area in 2002 were used for the image processing analysis. Classification of different soil salinities was carried out using common algorithms of image classification based on the best composition bands and using statistical methods between soil salinity variables and digital numbers of the images to represent a suitable method. the research results showed that the reflective bands 7, 3, 4 and 1 are the best band composition for preparing the color composite images and for the classification of the salinity in this area. The highest coefficient of determination was R2=0.311 and R2=0.44 for saline and non-saline soil respectively using band 2 and 3 of the images at 5% significant level. Based on the results, it can be concluded that the potential of ETM+ images for delineation and identification of different soil salinity are limited.

  17. Effects of Soil Salinity on Sucrose Metabolism in Cotton Leaves.

    Directory of Open Access Journals (Sweden)

    Jun Peng

    Full Text Available This study investigated sucrose metabolism of the youngest fully expanded main-stem leaf (MSL and the subtending leaf of cotton (Gossypium hirsutum L. boll (LSCB of salt-tolerant (CCRI-79 and salt-sensitive (Simian 3 cultivars and its relationship to boll weight under low, medium and high soil salinity stress in Dafeng, China, in 2013 and 2014. The results showed that with increased soil salinity, 1 both the chlorophyll content and net photosynthetic rate (Pn decreased, while the internal CO2 concentration firstly declined, and then increased in the MSL and LSCB; 2 carbohydrate contents in the MSL reduced significantly, while sucrose and starch contents in the LSCB increased, as did the activities of sucrose phosphate synthase (SPS and sucrose synthase (SuSy in both the MSL and LSCB; 3 but invertase activity in both the MSL and LSCB did not change significantly. Our study also showed that the LSCB was more sensitive to soil salinity than was the MSL. Of the measured physiological indices, higher SPS activity, mainly controlled by sps3, may contribute to adaption of the LSCB to soil salinity stress because SPS is beneficial for efficiently sucrose synthesis, reduction of cellular osmotic potential and combined actions of Pn, and sucrose transformation rate and SPS may contribute to the reduction in boll weight under soil salinity stress.

  18. Assessment and field-scale mapping of soil quality properties of a saline-sodic soil

    NARCIS (Netherlands)

    Corwin, D.L.; Kaffka, S.R.; Hopmans, J.W.; Mori, Y.; Groenigen, van J.W.; Kessel, van C.; Lesch, S.M.; Oster, J.S.

    2003-01-01

    Salt-affected soils could produce useful forages when irrigated with saline drainage water. To assess the productive potential and sustainability of using drainage water for forage production, a saline-sodic site (32.4 ha) in California's San Joaquin Valley was characterized for soil quality. The

  19. Wheat Response to a Soil Previously Irrigated with Saline Water

    Directory of Open Access Journals (Sweden)

    Vito Sardo

    2011-02-01

    Full Text Available A research was conducted aimed at assessing the response of rainfed, lysimeter-grown wheat to various levels of soil salinity, in terms of dry mass production, inorganic and organic components, sucrose phosphate synthase (SPS and sucrose synthase (SS activity. One additional scope was the assessment of soil ability to recover from applied salts by means of winter precipitations. The results confirmed the relatively high salt tolerance of wheat, as demonstrated by the mechanisms enacted by plants to contrast salinity at root and leaf level. Some insight was gained in the relationships between salinity and the various inorganic and organic components, as well as with SPS and SS activity. It was demonstrated that in a year with precipitations well below the average values (305 mm vs 500 the leaching action of rain was sufficient to eliminate salts accumulated during summer irrigation with saline water.

  20. Salinization of soil over saline-sodic overburden from the oil sands in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, S.; Dobchuk, B.S. [O' Kane Consultants Inc., Saskatoon, SK (Canada); Barbour, S.L. [Saskatchewan Univ., Saskatoon, SK (Canada). College of Engineering; Van Rees, K.C.J. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Agricultural and Bioresource Engineering

    2010-11-15

    This paper characterized the 4-year evolution of salinity profiles in the reclaimed soil covers placed over saline-sodic overburden in the Athabasca region of Alberta, evaluated the influence of cover thickness and salt redistribution in the reclaimed material, and sought to identify the dominant mechanism of salt transport contributing to these profiles. A comparison of 4 reclamation treatments showed that salts accumulated in the cover soils, increasing the electrical conductivity in the lower part of the soils to levels exceeding the acceptable value for plant growth. Diffusion and not slope position was found to be the predominant mechanism driving the salt redistribution in the soils, at least for the 4-year period under observation. The cover thickness had no effect on the extent of salt ingress, but the average salinity for thinner soils was substantially higher than the average for thicker covers. The higher salinity levels compromised the overall quality of the thinner covers for vegetative growth. The thicker covers performed better as a reclamation prescription because the water storage capacity above the salt-affected zone was sufficient for the maintenance of vegetative communities. 46 refs., 2 tabs., 6 figs.

  1. Climate and soil salinity in the deserts of Central Asia

    Science.gov (United States)

    Pankova, E. I.; Konyushkova, M. V.

    2013-07-01

    A comparative analysis of climatic and soil salinity characteristics of the deserts of Central Asia, including deserts of the Turan Depression, the Gobi Desert, and deserts of the Dzungar and Tarim depressions was performed. The climatic characteristics—the degree of aridity, the degree of continentality, and the amount and regime of precipitation—are different in these deserts. No direct relationships between the areas occupied by the automorphic salt-affected soils and the aridity of the climate are observed in the studied regions. In the automorphic landscapes of Asian deserts, the degree and chemistry of the soil salinization and the distribution of salt-affected soils are controlled by the history of the particular territories rather than by their modern climatic conditions. The presence and properties of the salt-bearing rocks and the eolian migration of salts play the most significant role. The deficit of moisture in the modern climate favors the preservation of salt accumulations in places of their origin. The specific features of the climate, including the regime of precipitation, affect the redistribution of salts in the profiles of automorphic salt-affected soils. An increase in the degree of climatic continentality is accompanied by the decrease in the intensity of weathering and initial accumulation of salts. A different situation is observed in the soils of hydromorphic desert landscapes, in which the degree of salinity of the surface horizons and the area occupied by salt-affected soils are directly influenced by the modern climatic conditions.

  2. Effects of imidacloprid on soil microbial communities in different saline soils.

    Science.gov (United States)

    Zhang, Qingming; Xue, Changhui; Wang, Caixia

    2015-12-01

    The effects of imidacloprid in the soil environment are a worldwide concern. However, the impact of imidacloprid on soil microorganisms under salt stress is almost unknown. Therefore, an indoor incubation test was performed, and the denaturing gradient gel electrophoresis (DGGE) approach was used to determine the response of different saline soil bacterial and fungal community structures to the presence of imidacloprid (0.4, 2, 10 mg kg(-1)). The results showed that the soil bacterial diversity slightly declined with increasing imidacloprid concentration in soils with low salinity. In moderately saline soils, a new band in the DGGE profile suggested that imidacloprid could improve the soil bacterial diversity to some degree. An analysis of variance indicated that the measured soil bacterial diversity parameters were significantly affected by dose and incubation time. Compared with the control, the soil fungal community structure showed no obvious changes in low and moderately saline soils treated with imidacloprid. The results of these observations provide a basic understanding of the potential ecological effects of imidacloprid on different microorganisms in saline soils.

  3. Impacts of Evaporation from Saline Soils on Soil Hydraulic Properties and Water Fluxes

    Science.gov (United States)

    Fierro, V.; Hernandez, M. F.; Braud, I.; Cristi Matte, F.; Hausner, M. B.; Suarez, F. I.; Munoz, J.

    2013-12-01

    Saline soils are common in arid zones, where evaporation from shallow groundwater is generally the major component of the water balance. Thus, accurate quantification of soil water evaporation is crucial to improve water resource management in these regions. Evaporation from saline soils is a complex process that couples the movement of salts, heat, liquid water and water vapor. Precipitation/dissolution reactions can alter the soil structure and modify flow paths. The impact of evaporation from shallow groundwater on soil properties and water fluxes poses a major hydrologic challenge that remains to be answered. As a preliminary approach to consider these effects, we used the SiSPAT model (Simple Soil Plant Atmospheric Transfer) to represent the movement of liquid water and water vapor in a saline soil column subjected to two groundwater levels under nonisothermal conditions. To parameterize the model, we determined the hydraulic properties of the soil before performing the soil column experiments. When the SiSPAT model was run using uniform and constant hydraulic properties, it was unable to predict the moisture and thermal profiles, or the cumulative evaporation. This inability to reproduce the observed data is most likely due to alterations of the soil structure as a result of precipitation/dissolution reactions. When the soil hydraulic properties were allowed to vary in space, the model reproduced the experimental data successfully, suggesting that the structure of the initially homogeneous soil column was modified. It is thus necessary to incorporate salt precipitation to correctly simulate evaporation in saline soils.

  4. Accumulation of oxytetracycline and norfloxacin from saline soil by soybeans.

    Science.gov (United States)

    Boonsaner, M; Hawker, D W

    2010-03-01

    Soil of former shrimp aquaculture facilities in Thailand may be contaminated by antibiotics (e.g. oxytetracycline and norfloxacin) and have elevated salinity. Therefore, reuse of this land can be problematic. The utility of soybean (Glycine max (L.) Merr.) for phytoremediation was investigated. The rate of germination and seedling emergence in prepared contaminated soil (conductivity 17.7 dS m(-1) from adding 70 mg sodium chloride g(-1) dry weight, 105 mg kg(-1) dry weight oxytetracycline and 55 mg kg(-1) dry weight norfloxacin) in sunlight was approximately 80% that of uncontaminated soil. This reduction was largely due to the high salinity. The antibiotics of interest degraded relatively rapidly in soil (half-life removal of NaCl from soil adjacent to plant roots was observed, most within two days. Wilting and defoliation occurred, but plants recovered after 10 days and maximum salt levels in plants exceeded 20,000 mg g(-1) dry weight with translocation from root to shoot tissue noted. Soybean plants also accumulated the antibiotics from prepared contaminated saline soil, but translocation from the roots was not observed. The results showed that soybean can be valuable for phytoremediation in these situations.

  5. Irrigation and Soil Salinization in Mediterranean agro-ecosystem

    Science.gov (United States)

    Ortega, Angelo; Viola, Francesco; Valerio Noto, Leonardo; Mau, Yair; Porporato, Amilcare

    2015-04-01

    During the warm and dry growing season of Mediterranean climates, the availability of good quality water for primary production in agriculture tends to be limited. This aspect makes the use of saline and brackish water appealing, given the potential of natural flushing of the soils by deep percolation during the wet and colder dormant season. Thus the cyclic alternation between the two different phases in the cold and warm season gives rise to a delicate equilibrium that can lead to long term secondary salinization if the mean salt input from irrigation overpasses the average annual natural leakage amount. The main goal of this study is to evaluate the long term salt mass balance in the presence of irrigation and possible changes in seasonality. An elevated concentration of salt in the soil may in turn lead to both a decrease of its fertility and to osmotic stress reducing plant productivity. To this purpose, a stochastic soil and water balance salinity model is developed to quantify the balance between salt accumulation phases during the growing season and leaching phases during the wet season. We provide the numerical and the analytical representation of secondary long-term salinization process, highlighting the role of soil depth, plant and climate together with the impact of shifts in the seasonal vs. interannual rainfall fluctuations. An application to a test case in the Southern part of Sicily (ITALY) is also presented, highlighting the strong relationship between salt dynamics, water management and climatic conditions.

  6. Sustainable management of coastal saline soils in the Saloum river ...

    African Journals Online (AJOL)

    between landscape position and soil salinity illustrated by a two-dimensional salt distribution pattern: ... 2011). Salt accumulation in shallow groundwater systems has been observed in a range of wetland environments, including the swamps of the. Okavango Delta, Botswana ...... mulching benefits the conservation of water,.

  7. Modelling of soil salinity and halophyte crop production

    NARCIS (Netherlands)

    Vermue, E.; Metselaar, K.; Zee, van der S.E.A.T.M.

    2013-01-01

    In crop modelling the soil, plant and atmosphere system is regarded as a continuum with regard to root water uptake and transpiration. Crop production, often assumed to be linearly related with transpiration, depends on several factors, including water and nutrient availability and salinity. The

  8. Nonlinear Allometric Equation for Crop Response to Soil Salinity

    Directory of Open Access Journals (Sweden)

    E. Misle

    2015-06-01

    Full Text Available Crop response to soil salinity has been extensively studied, from empirical works to modelling approach, being described by different equations, first as a piecewise linear model. The equation employed can differ with actual response, causing miscalculation in practical situations, particularly at the higher extremes of the curve. The aim of this work is to propose a new equation, which allows determining the full response to salinity of plant species and to provide a verification using different experimental data sets. A new nonlinear equation is exposed supported by the allometric approach, in which the allometric exponent is salinity-dependent and decreases with the increase in relative salinity. A conversion procedure of parameters of the threshold-slope model is presented; also, a simple procedure for estimating the maximum salinity (zero-yield point when data sets are incomplete is exposed. The equation was tested in a wide range of experimental situations, using data sets from published works, as well as new measurements on seed germination. The statistical indicators of quality (R2, absolute sum of squares and standard deviation of residuals showed that the equation accurately fits the tested empirical results. The new equation for determining crop response to soil salinity is able to follow the response curve of any crop with remarkable accuracy and flexibility. Remarkable characteristics are: a maximum at minimum salinity, a maximum salinity point can be found (zero-yield depending on the data sets, and a meaningful inflection point, as well as the two points at which the slope of the curve equals unity, can be found.

  9. Assessment of soil salinization risks under irrigation with brackish water in semiarid Tunesia

    NARCIS (Netherlands)

    Bouksila, F.; Bahrib, A.; Berndtsson, R.; Persson, M.; Rozema, J.; Zee, van der S.E.A.T.M.

    2013-01-01

    The salinity problem is becoming increasingly widespread in arid countries. In semiarid Tunisia about 50% of the irrigated land is considered as highly sensitive to salinization. To avoid the risk of salinization, it is important to control the soil salinity and keep it below plant salinity

  10. Assessment of soil salinization risks under irrigation with brackish water in semiarid Tunisia

    NARCIS (Netherlands)

    Bouksila, F.; Bahri, A.; Berndtsson, R.; Persson, M; Rozema, J.; van der Zee, S.E.A.T.M.

    2013-01-01

    The salinity problem is becoming increasingly widespread in arid countries. In semiarid Tunisia about 50% of the irrigated land is considered as highly sensitive to salinization. To avoid the risk of salinization, it is important to control the soil salinity and keep it below plant salinity

  11. Can Tomato Inoculation with Trichoderma Compensate Yield and Soil Health Deficiency due to Soil Salinity?

    Science.gov (United States)

    Wagner, Karl; Apostolakis, Antonios; Daliakopoulos, Ioannis; Tsanis, Ioannis

    2016-04-01

    Soil salinity is a major soil degradation threat, especially for arid coastal environments where it hinders agricultural production and soil health. Protected horticultural crops in the Mediterranean region, typically under deficit irrigation and intensive cultivation practices, have to cope with increasing irrigation water and soil salinization. This study quantifies the beneficial effects of the Trichoderma harzianum (TH) on the sustainable production of Solanum lycopersicum (tomato), a major greenhouse crop of the RECARE project Case Study in Greece, the semi-arid coastal Timpaki basin in south-central Crete. 20 vigorous 20-day-old Solanum lycopersicum L. cv Elpida seedlings are treated with TH fungi (T) or without (N) and transplanted into 35 L pots under greenhouse conditions. Use of local planting soil with initial Electrical Conductivity (ECe) 1.8 dS m-1 and local cultivation practices aim to simulate the prevailing conditions at the Case Study. In order to simulate seawater intrusion affected irrigation, plants are drip irrigated with two NaCl treatments: slightly (S) saline (ECw = 1.1 dS m-1) and moderately (M) saline water (ECw = 3.5 dS m-1), resulting to very high and excessively high ECe, respectively. Preliminary analysis of below and aboveground biomass, soil quality, salinity, and biodiversity indicators, suggest that TH pre-inoculation of tomato plants at both S and M treatments improve yield, soil biodiversity and overall soil health.

  12. Spatiotemporal Distribution of Soil Moisture and Salinity in the Taklimakan Desert Highway Shelterbelt

    Directory of Open Access Journals (Sweden)

    Yuan Huang

    2015-08-01

    Full Text Available Salinization and secondary salinization often appear after irrigation with saline water. The Taklimakan Desert Highway Shelterbelt has been irrigated with saline ground water for more than ten years; however, soil salinity in the shelterbelt has not been evaluated. The objective of this study was to analyze the spatial and temporal distribution of soil moisture and salinity in the shelterbelt system. Using a non-uniform grid method, soil samples were collected every two days during one ten-day irrigation cycle in July 2014 and one day in spring, summer, and autumn. The results indicated that soil moisture declined linearly with time during the irrigation cycle. Soil moisture was greatest in the southern and eastern sections of the study area. In contrast to soil moisture, soil electrical conductivity increased from 2 to 6 days after irrigation, and then gradually decreased from 6 to 8 days after irrigation. Soil moisture was the greatest in spring and the least in summer. In contrast, soil salinity increased from spring to autumn. Long time drip-irrigation with saline groundwater increased soil salinity slightly. The soil salt content was closely associated with soil texture. The current soil salt content did not affect plant growth, however, the soil in the shelterbelt should be continuously monitored to prevent salinization in the future.

  13. Soil Salinity Retrieval from Advanced Multi-Spectral Sensor with Partial Least Square Regression

    Directory of Open Access Journals (Sweden)

    Xingwang Fan

    2015-01-01

    Full Text Available Improper use of land resources may result in severe soil salinization. Timely monitoring and early warning of soil salinity is in urgent need for sustainable development. This paper addresses the possibility and potential of Advanced Land Imager (ALI for mapping soil salinity. In situ field spectra and soil salinity data were collected in the Yellow River Delta, China. Statistical analysis demonstrated the importance of ALI blue and near infrared (NIR bands for soil salinity. A partial least square regression (PLSR model was established between soil salinity and ALI-convolved field spectra. The model estimated soil salinity with a R2 (coefficient of determination, RPD (ratio of prediction to deviation, bias, standard deviation (SD and root mean square error (RMSE of 0.749, 3.584, 0.036 g∙kg−1, 0.778 g∙kg−1 and 0.779 g∙kg−1. The model was then applied to atmospherically corrected ALI data. Soil salinity was underestimated for moderately (soil salinity within 2–4 g∙kg−1 and highly saline (soil salinity >4 g∙kg−1 soils. The underestimates increased with the degree of soil salinization, with a maximum value of ~4 g∙kg−1. The major contribution for the underestimation (>80% may result from data inaccuracy other than model ineffectiveness. Uncertainty analysis confirmed that improper atmospheric correction contributed to a very conservative uncertainty of 1.3 g∙kg−1. Field sampling within remote sensing pixels was probably the major source responsible for the underestimation. Our study demonstrates the effectiveness of PLSR model in retrieving soil salinity from new-generation multi-spectral sensors. This is very valuable for achieving worldwide soil salinity mapping with low cost and considerable accuracy.

  14. Impacts of irrigation regimes with saline water on carrot productivity and soil salinity

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2012-01-01

    Full Text Available A three-year study was conducted to evaluate the effects of different irrigation regimes with saline water on soil salinity, yield and water productivity of carrot as a fall-winter crop under actual commercial-farming conditions in the arid region of Tunisia. Carrot was grown on a sandy soil and surface-irrigated with a water having an ECi of 3.6 dS/m. For the three years, a complete randomized block design with four replicates was used to evaluate five irrigation regimes. Four irrigation methods were based on the use of soil water balance (SWB to estimate irrigation amounts and timing while the fifth consisted of using traditional farmers practices. SWB methods consisted in replacement of cumulated ETc when readily available water is depleted with levels of 100% (FI-100, 80% (DI-80 and 60% (DI-60. FI-100 was considered as full irrigation while DI-80 and DI-60 were considered as deficit irrigation regimes. Regulated deficit irrigation regime where 40% reduction is applied only during ripening stage (FI-DI60 was also used. Farmer method (Farmer consisted in giving fixed amounts of water (25 mm every 7 days from planting till harvest. Results on carrot production and soil salinization are globally consistent between the three-year experiments and shows significant difference between irrigation regimes. Higher soil salinity in the root zone is observed at harvest under DI-60 (3.1, 3.4, 3.9 dS/m, respectively, for the three years and farmer irrigation (3.3, 3.6, 3.9 dS/m treatments compared to FI-100 treatment (2.3, 2.6 and 3.1 dS/m. Relatively low ECe values were also observed under FI-DI60 and DI-80 treatments with respectively (2.7, 3, 3.5 dS/m and (2.5, 2.9, 3.3 dS/m. ECe values under the different irrigation treatments were generally lower than or equal to the EC of irrigation water used. Rainfall received during fall and/or winter periods (57, 26 and 29 mm, respectively, during the three years contributed probably to leaching soluble

  15. Soil salinity and moisture measurement system for grapes field by wireless sensor network

    Directory of Open Access Journals (Sweden)

    M.K. Bhanarkar

    2016-12-01

    Full Text Available Soil moisture and salinity measurement are the essential factors for crop irrigation as well as to increase the yield. Grapes eminence depends on the water volume contents in soil and soil nutrients. Based on these conditions, we determined water demand for best quality of grapes by wireless sensor network (WSN. Using lot of chemical fertilizers increases soil salinity but reduces soil fertility, soil salinity defines electrical conductivity or salty soil. Precise agriculture systems are integrated with multiple sensors to monitor and control the incident. Integrated WSN is designed and developed to measure soil moisture and salinity. ATmega328 microcontroller, XBee and Soil sensors are integrated across the system. This system is more competent, it can be helpful to automatic irrigation system and soil salinity monitoring.

  16. Prediction of SWCC of Saline Soil in Western Jilin Based on Arya-Paris Model

    Directory of Open Access Journals (Sweden)

    Bao Shuochao

    2016-01-01

    Full Text Available The saline soil distributed in Western Jilin Province could cause a serious of damages to local construction engineering and agriculture. The relationship between water content and soil suction has great influence on engineering properties, and effect the water migration and forming of saline soil. This paper aims to the saline soil in Zhenlai area of Western Jilin province, the basic properties test were taken in laboratory, and Arya-Paris prediction model were chosen to predict the SWCC of saline soil in Western Jilin. The results show that the 30cm soil sample has lower water holding capacity than the 50cm soil sample, which means the water migration rate is higher of 30cm. The results may provide theoretical support and beneficial reference for research and prediction of engineering properties and forming mechanism of saline soil.

  17. Calibration of capacitance probe sensors in a saline silty clay soil

    NARCIS (Netherlands)

    Kelleners, T.J.; Soppe, R.W.O.; Ayars, J.E.; Skaggs, T.H.

    2004-01-01

    Capacitance probe sensors are a popular electromagnetic method of measuring soil water content. However, there is concern about the influence of soil salinity on the sensor readings. In this study capacitance sensors are calibrated for a saline silty clay soil. An electric circuit model is used to

  18. Naturally occurring soil salinity does not reduce N-transforming enzymes or organisms

    Science.gov (United States)

    Soil salinity can negatively affect plant production and important biogeochemical cycles which are mainly carried out by soil microbes. The objective of this study was to contribute new information on soil biological N transformations by examining the impact primary salinity reduction has on a) the ...

  19. Simplifying field-scale assessment of spatiotemporal changes of soil salinity

    Science.gov (United States)

    Monitoring soil salinity (ECe) is important to properly plan agronomic and irrigation practices. Salinity can be readily measured through soil sampling directed by geospatial measurements of apparent soil electrical conductivity (ECa). Using data from a long-term (1999-2012) monitoring study at a 32...

  20. Influence of Microsprinkler Irrigation Amount on Water, Soil, and pH Profiles in a Coastal Saline Soil

    Directory of Open Access Journals (Sweden)

    Linlin Chu

    2014-01-01

    Full Text Available Microsprinkler irrigation is a potential method to alleviate soil salinization. After conducting a homogeneous, highly saline, clayey, and coastal soil from the Bohai Gulf in northern China in a column experiment, the results show that the depth of the wetting front increased as the water amount applied increased, low-salinity and low-SAR enlarged after irrigation and water redistribution, and the soil pH increased with an increase in irrigation amount. We concluded that a water amount of 207 mm could be used to reclaim the coastal saline soil in northern China.

  1. Cellulolytic activity of some cellulose-decomposing fungi in salinized soils

    Directory of Open Access Journals (Sweden)

    R. A. Badran

    2014-08-01

    Full Text Available Maximum evolution of CO2 was marked in control soil inoculated by tested fungi but its rate decreased with the increasing salinity. The period of 10 days was most suitable for cellulose degradation by A. niger and P. chrysoecnum and 15 days by A. flavus and C. globosum in control soil. High salinity levels affected greatly the cellulolylic activities of tesled fungi. Carbon content of saline soils increased white the nitrogen content decreased.

  2. Effects of soil salinity on the content, composition, and ion binding capacity of glomalin-related soil protein (GRSP).

    Science.gov (United States)

    Zhang, Zhonghua; Wang, Qiong; Wang, Hua; Nie, Siming; Liang, Zhengwei

    2017-03-01

    Soil aggregation, an ecosystem function correlated with the concentration of glomalin-related soil protein (GRSP), is highly disturbed in saline soil. However, few studies have focused on differences in amount, composition, and ion binding capacity of GRSP in typical sodic-saline soils. In this study, a field study was performed in Songnen Plain. Combined indicators of soil salinity (Q value) were significant negatively correlated with GRSP concentration by Principal Component Analysis. Multiple linear regression models showed that soil salinity might account for 46%, 25% and 44% variation in total GRSP (T-GRSP), easily-extractable GRSP (EE-GRSP) and difficultly-extractable GRSP (DE-GRSP), respectively. Soil bulk density had most important impact on GRSP concentration, followed by the pH, soil EC had the weak influence. Comparative analysis was carried out between low-salinity and high-salinity soil. Purified T-GRSP of high-saline soil contained higher N content (13.13%), lower C content (43.41%) and lower functional groups relative content (e.g. CO and SiOSi). Purified T-GRSP of high-salinity soil had a greater binding capacity with calcium and phosphorus, the binding capacity could compensate the GRSP loss about 29.8% and 14.1%, respectively. Our findings suggested that sodic salinization of the soil led to a decrease in GRSP concentration and a change in the component percentages. This change in composition might be related to adaptation of fungi-plant systems to varied environments. The calcium and phosphorus binding capacity had a positive dependent of soil salinization, which was possible to develop ecological management or recovery technology in the future. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Capillary rise simulation of saline waters of different concentrations in sandy soils

    Directory of Open Access Journals (Sweden)

    Natthawit Jitrapinate

    2016-06-01

    Full Text Available Soil salinity causes corrosion of engineering structures worldwide. The main cause of soil salinization is capillary rise of saline groundwater. Soil salinity can be mitigated once the capillary rise of saline groundwater in soils is understood. The objective of this paper is to present experimental results of capillary rising rates of different salt concentration waters in three sandy soils. Each sample comprised of a soil column 300-mm height and 50-mm in diameter steeped in a 25-mm deep saline water pool for a time period to allow for the capillary action to develop. The salinity strength varied from fresh water, EC = 2 dS/m, to medium saline (50, 100, and 150 dS/m, and to high saline water (200 dS/m. It was found that the highest rate of capillary rise occurred in medium saline waters, while the lowest is the fresh water. The very saline water has lower rate than the medium ones but higher than fresh water.

  4. Soil salinity: Germination tolerance of alternative oilseed crops for soil health

    Science.gov (United States)

    World-wide, saline soils contribute to over US$27.3 billion in agricultural losses annually by reducing plant growth through osmotic imbalances and ion toxicity. Nearly 800,000 ha of salt affected land is located in the northern Great Plains. Limited information is available on the germination of al...

  5. Soil salinity and yield of mango fertigated with potassium sources

    Directory of Open Access Journals (Sweden)

    Marcio A. Carneiro

    Full Text Available ABSTRACT Irrigated fruit crops have an important role in the economic and social aspects in the region of the Sub-middle São Francisco River Valley. Thus, the aim of this study was to evaluate soil salinity and the productive aspects of the mango crop, cv. Tommy Atkins, fertigated with doses of potassium chloride (KCl and potassium sulfate (K2SO4 during two crop cycles (from January to March 2014 and from January to March 2015. The experiment was carried out in a strip-split-plot design and five potassium doses (50, 75, 100, 125 and 150% of the recommended dose as plots and two potassium sources (KCl and K2SO4 as subplots, with four replicates. Soil electrical conductivity (EC, exchangeable sodium (Na+ and potassium (K+ contents and pH were evaluated. In addition, the number of commercial fruits and yield were determined. The fertilization with KCl resulted in higher soil EC compared with K2SO4 fertigation. Soil Na+ and K+ contents increased with increasing doses of fertilizers. K2SO4 was more efficient for the production per plant and yield than KCl. Thus, under the conditions of this study, the K2SO4 dose of 174.24 g plant-1 (24.89 kg ha-1 or 96.8% of recommendation, spacing of 10 x 7 m was recommended for a yield of 23.1 t ha-1 of mango fruits, cv. Tommy Atkins.

  6. Contributions of groundwater conditions to soil and water salinization

    Science.gov (United States)

    Salama, Ramsis B.; Otto, Claus J.; Fitzpatrick, Robert W.

    Salinization is the process whereby the concentration of dissolved salts in water and soil is increased due to natural or human-induced processes. Water is lost through one or any combination of four main mechanisms: evaporation, evapotranspiration, hydrolysis, and leakage between aquifers. Salinity increases from catchment divides to the valley floors and in the direction of groundwater flow. Salinization is explained by two main chemical models developed by the authors: weathering and deposition. These models are in agreement with the weathering and depositional geological processes that have formed soils and overburden in the catchments. Five soil-change processes in arid and semi-arid climates are associated with waterlogging and water. In all represented cases, groundwater is the main geological agent for transmitting, accumulating, and discharging salt. At a small catchment scale in South and Western Australia, water is lost through evapotranspiration and hydrolysis. Saline groundwater flows along the beds of the streams and is accumulated in paleochannels, which act as a salt repository, and finally discharges in lakes, where most of the saline groundwater is concentrated. In the hummocky terrains of the Northern Great Plains Region, Canada and USA, the localized recharge and discharge scenarios cause salinization to occur mainly in depressions, in conjunction with the formation of saline soils and seepages. On a regional scale within closed basins, this process can create playas or saline lakes. In the continental aquifers of the rift basins of Sudan, salinity increases along the groundwater flow path and forms a saline zone at the distal end. The saline zone in each rift forms a closed ridge, which coincides with the closed trough of the groundwater-level map. The saline body or bodies were formed by evaporation coupled with alkaline-earth carbonate precipitation and dissolution of capillary salts. Résumé La salinisation est le processus par lequel la

  7. Stochastic and deterministic models of soil salinity in the root zone

    Science.gov (United States)

    Aljoumani, Basem; Peters, Andre; Trinks, Steffen; Wessolek, Gerd

    2015-04-01

    Salinization is a significant cause of land degradation and nutrient deficiency. Understanding and predicting soil salinity is important for optimizing and scheduling irrigation in order to maintain sustainable agriculture. The aim of this work is to develop and apply time series analysis to measured water and salinity dynamics in soils for a prediction of salinity with limited information. Therefore, volumetric water content, soil temperature, and bulk electrical conductivity will be measured in situ by capacitance sensors at various depths within a laboratory soil column. Time series analysis will be applied to predict water and salinity dynamics on basis of data taken at one or two depth. Prediction of soil salinity obtained by time series will be compared with the measured data at other depths as well as to results obtained by numerical simulation of water and salt dynamics for variably saturated flow with HYDRUS 1D.

  8. Is soil microbial diversity affected by soil and groundwater salinity? Evidences from a coastal system in central Italy.

    Science.gov (United States)

    Canfora, Loredana; Salvati, Luca; Benedetti, Anna; Francaviglia, Rosa

    2017-07-01

    Little is known about composition, diversity, and abundance of microbial communities in environments affected by primary soil salinization, such as coastal lagoon systems. The main objective of this study was to investigate the impact of lagoon salinity, soil type, and land-use on inland soil and groundwater quality, and soil microbial community structure, diversity, and gene abundance, as evaluated by T-RFLP (terminal-restriction fragment length polymorphism) and qPCR (quantitative polymerase-chain-reaction). For this purpose, four sites oriented along a groundwater salinity gradient (Fogliano lagoon, central Italy) were studied under different recreational, grazing, and land-use conditions. Spatial variability in groundwater attributes was observed depending on salinity and soil electrical conductivity, both influenced by salt intrusion. A comparison of community abundance and number of phylotypes of bacteria, archaea, and fungi across varying soil depths pointed out marked differences across soils characterized by different soil type, land-use, and salinity. The latter significantly affected the microbial population richness and diversity and showed a dominance in terms of bacteria species. Our study provides a comprehensive overview of the spatial relationship between soil microbial community and soil degradation processes along a relatively underexplored environmental gradient in a coastal system, coming to the conclusion that salinity acts differently as a driver of microbial community structure in comparison with other saline environments.

  9. Moving Forward on Remote Sensing of Soil Salinity at Regional Scale

    Directory of Open Access Journals (Sweden)

    Elia Scudiero

    2016-10-01

    Full Text Available Soil salinity undermines global agriculture by reducing crop yield and impairing soil quality. Irrigation management can help control salinity levels within the soil root-zone. To best manage water and soil resources, accurate regional-scale inventories of soil salinity are needed. The past decade has seen several successful applications of soil salinity remote sensing. Two salinity remote sensing approaches exist: direct assessment based on analysis of surface soil reflectance (the most popular approach, and indirect assessment of root-zone (e.g., 0-1 m soil salinity based on analysis of crop canopy reflectance. In this perspective paper, we call on researchers and funding agencies to pay greater attention to the indirect approach because it is better suited for surveying agriculturally important lands. A joint effort between agricultural producers, irrigation specialists, environmental scientists, and policy makers is needed to better manage saline agricultural soils, especially because of projected future water scarcity in arid and semi-arid irrigated areas. The remote sensing community should focus on providing the best tools for mapping and monitoring salinity in such areas, which are of vital relevance to global food production.

  10. Water Use Efficiency in Saline Soils under Cotton Cultivation in the Tarim River Basin

    Directory of Open Access Journals (Sweden)

    Xiaoning Zhao

    2015-06-01

    Full Text Available The Tarim River Basin, the largest area of Chinese cotton production, is receiving increased attention because of serious environmental problems. At two experimental stations (Korla and Aksu, we studied the influence of salinity on cotton yield. Soil chemical and physical properties, soil water content, soil total suction and matric suction, cotton yield and water use efficiency under plastic mulched drip irrigation in different saline soils was measured during cotton growth season. The salinity (mS·cm−1 were 17–25 (low at Aksu and Korla, 29–50 (middle at Aksu and 52–62 (high at Aksu for ECe (Electrical conductivity measured in saturation-paste extract of soil over the 100 cm soil profile. The soil water characteristic curves in different saline soils showed that the soil water content (15%–23% at top 40 cm soil, lower total suction power (below 3500 kPa and lower matric suction (below 30 kPa in low saline soil at Korla had the highest water use efficiency (10 kg·ha−1·mm−1 and highest irrigation water use efficiency (12 kg·ha−1·mm−1 and highest yield (6.64 t·ha−1. Higher water content below 30 cm in high saline soil increased the salinity risk and led to lower yield (2.39 t·ha−1. Compared to low saline soils at Aksu, the low saline soil at Korla saved 110 mm irrigation and 103 mm total water to reach 1 t·ha−1 yield and increased water use efficiency by 5 kg·ha−1·mm−1 and 7 kg·ha−1·mm−1 for water use efficiency (WUE and irrigation water use efficiency (IWUE respectively.

  11. Simulation of Quinoa (Chenopodium Quinoa Willd.) response to soil salinity using the saltmed model

    DEFF Research Database (Denmark)

    Razzaghi, Fatemeh; Plauborg, Finn; Ahmadi, Seyed Hamid

    Quinoa (Chenopodium quinoa Willd.) is a crop with high tolerance to salinity and drought and its response to varying soil moisture and salinity levels was studied in a field lysimeter experiment. Quinoa (cv. Titicaca) was irrigated with different concentrations of saline water (0, 10, 20, 30 and 40...

  12. Soil transport parameters of potassium under a tropical saline soil condition using STANMOD

    Science.gov (United States)

    Suzanye da Silva Santos, Rafaelly; Honorio de Miranda, Jarbas; Previatello da Silva, Livia

    2015-04-01

    Environmental responsibility and concerning about the final destination of solutes in soil, so more studies allow a better understanding about the solutes behaviour in soil. Potassium is a macronutrient that is required in high concentrations, been an extremely important nutrient for all agricultural crops. It plays essential roles in physiological processes vital for plant growth, from protein synthesis to maintenance of plant water balance, and is available to plants dissolved in soil water while exchangeable K is loosely held on the exchange sites on the surface of clay particles. K will tend to be adsorbed onto the surface of negatively charged soil particles. Potassium uptake is vital for plant growth but in saline soils sodium competes with potassium for uptake across the plasma membrane of plant cells. This can result in high Na+:K+ ratios that reduce plant growth and eventually become toxic. This study aimed to obtain soil transport parameters of potassium in saline soil, such as: pore water velocity in soil (v), retardation factor (R), dispersivity (λ) and dispersion coefficient (D), in a disturbed sandy soil with different concentrations of potassium chlorate solution (KCl), which is one of the most common form of potassium fertilizer. The experiment was carried out using soil samples collected in a depth of 0 to 20 cm, applying potassium chlorate solution containing 28.6, 100, 200 and 500 mg L-1 of K. To obtain transport parameters, the data were adjusted with the software STANMOD. At low concentrations, interaction between potassium and soil occur more efficiently. It was observed that only the breakthrough curve prepared with solution of 500 mg L-1 reached the applied concentration, and the solution of 28.6 mg L-1 overestimated the parameters values. The STANMOD proved to be efficient in obtaining potassium transport parameters; KCl solution to be applied should be greater than 500 mg L-1; solutions with low concentrations tend to overestimate

  13. Mapping spatial variability of soil salinity in a coastal paddy field based on electromagnetic sensors.

    Science.gov (United States)

    Guo, Yan; Huang, Jingyi; Shi, Zhou; Li, Hongyi

    2015-01-01

    In coastal China, there is an urgent need to increase land area for agricultural production and urban development, where there is a rapid growing population. One solution is land reclamation from coastal tidelands, but soil salinization is problematic. As such, it is very important to characterize and map the within-field variability of soil salinity in space and time. Conventional methods are often time-consuming, expensive, labor-intensive, and unpractical. Fortunately, proximal sensing has become an important technology in characterizing within-field spatial variability. In this study, we employed the EM38 to study spatial variability of soil salinity in a coastal paddy field. Significant correlation relationship between ECa and EC1:5 (i.e. r >0.9) allowed us to use EM38 data to characterize the spatial variability of soil salinity. Geostatistical methods were used to determine the horizontal spatio-temporal variability of soil salinity over three consecutive years. The study found that the distribution of salinity was heterogeneous and the leaching of salts was more significant in the edges of the study field. By inverting the EM38 data using a Quasi-3D inversion algorithm, the vertical spatio-temporal variability of soil salinity was determined and the leaching of salts over time was easily identified. The methodology of this study can be used as guidance for researchers interested in understanding soil salinity development as well as land managers aiming for effective soil salinity monitoring and management practices. In order to better characterize the variations in soil salinity to a deeper soil profile, the deeper mode of EM38 (i.e., EM38v) as well as other EMI instruments (e.g. DUALEM-421) can be incorporated to conduct Quasi-3D inversions for deeper soil profiles.

  14. Mapping spatial variability of soil salinity in a coastal paddy field based on electromagnetic sensors.

    Directory of Open Access Journals (Sweden)

    Yan Guo

    Full Text Available In coastal China, there is an urgent need to increase land area for agricultural production and urban development, where there is a rapid growing population. One solution is land reclamation from coastal tidelands, but soil salinization is problematic. As such, it is very important to characterize and map the within-field variability of soil salinity in space and time. Conventional methods are often time-consuming, expensive, labor-intensive, and unpractical. Fortunately, proximal sensing has become an important technology in characterizing within-field spatial variability. In this study, we employed the EM38 to study spatial variability of soil salinity in a coastal paddy field. Significant correlation relationship between ECa and EC1:5 (i.e. r >0.9 allowed us to use EM38 data to characterize the spatial variability of soil salinity. Geostatistical methods were used to determine the horizontal spatio-temporal variability of soil salinity over three consecutive years. The study found that the distribution of salinity was heterogeneous and the leaching of salts was more significant in the edges of the study field. By inverting the EM38 data using a Quasi-3D inversion algorithm, the vertical spatio-temporal variability of soil salinity was determined and the leaching of salts over time was easily identified. The methodology of this study can be used as guidance for researchers interested in understanding soil salinity development as well as land managers aiming for effective soil salinity monitoring and management practices. In order to better characterize the variations in soil salinity to a deeper soil profile, the deeper mode of EM38 (i.e., EM38v as well as other EMI instruments (e.g. DUALEM-421 can be incorporated to conduct Quasi-3D inversions for deeper soil profiles.

  15. Managing the Economics of Soil Salinity in the Red River Valley of North Dakota

    OpenAIRE

    Hadrich, Joleen

    2012-01-01

    Saline soils result in decreased crop growth and yield with the potential for losing productive farm land. Enterprise budget analysis was extended to include the fixed costs of installing tile drainage to manage soil salinity in the Red River Valley of North Dakota for corn, soybeans, wheat, sugar beets, and barley. Installing tile drainage decreased per acre crop profitability from 19 to 49 percent. Lost revenues were estimated to be $150 million due to 1.2 million acres of slightly saline s...

  16. Modeling daily soil salinity dynamics in response to agricultural and environmental changes in coastal Bangladesh

    Science.gov (United States)

    Payo, Andrés.; Lázár, Attila N.; Clarke, Derek; Nicholls, Robert J.; Bricheno, Lucy; Mashfiqus, Salehin; Haque, Anisul

    2017-05-01

    Understanding the dynamics of salt movement in the soil is a prerequisite for devising appropriate management strategies for land productivity of coastal regions, especially low-lying delta regions, which support many millions of farmers around the world. At present, there are no numerical models able to resolve soil salinity at regional scale and at daily time steps. In this research, we develop a novel holistic approach to simulate soil salinization comprising an emulator-based soil salt and water balance calculated at daily time steps. The method is demonstrated for the agriculture areas of coastal Bangladesh (˜20,000 km2). This shows that we can reproduce the dynamics of soil salinity under multiple land uses, including rice crops, combined shrimp and rice farming, as well as non-rice crops. The model also reproduced well the observed spatial soil salinity for the year 2009. Using this approach, we have projected the soil salinity for three different climate ensembles, including relative sea-level rise for the year 2050. Projected soil salinity changes are significantly smaller than other reported projections. The results suggest that inter-season weather variability is a key driver of salinization of agriculture soils at coastal Bangladesh.

  17. Mapping soil salinity in irrigated land using optical remote sensing data

    Directory of Open Access Journals (Sweden)

    Rachid Lhissoui

    2014-04-01

    Full Text Available Soil salinity caused by natural or human-induced processes is certainly a severe environmental problem that already affects 400 million hectares and seriously threatens an equivalent surface. Salinization causes negative effects on the ground; it affects agricultural production, infrastructure, water resources and biodiversity. In semi-arid and arid areas, 21% of irrigated lands suffer from waterlogging, salinity and/or sodicity that reduce their yields. 77 million hectares are saline soils induced by human activity, including 58% in the irrigated areas. In the irrigated perimeter of Tadla plain (central Morocco, the increased use of saline groundwater and surface water, coupled with agricultural intensification leads to the deterioration of soil quality. Experimental methods for monitoring soil salinity by direct measurements in situ are very demanding of time and resources, and also very limited in terms of spatial coverage. Several studies have described the usefulness of remote sensing for mapping salinity by its synoptic coverage and the sensitivity of the electromagnetic signal to surface soil parameters. In this study, we used an image of the TM Landsat sensor and field measurements of electrical conductivity (EC, the correlation between the image data and field measurements allowed us to develop a semi-empirical model allowing the mapping of soil salinity in the irrigated perimeter of Tadla plain. The validation of this model by the ground truth provides a correlation coefficient r² = 0.90. Map obtained from this model allows the identification of different salinization classes in the study area.

  18. Remote sensing is a viable tool for mapping soil salinity in agricultural lands

    Directory of Open Access Journals (Sweden)

    Elia Scudiero

    2017-04-01

    Full Text Available Soil salinity negatively impacts the productivity and profitability of western San Joaquin Valley (WSJV farmland. Many factors, including drought, climate change, reduced water allocations, and land-use changes could worsen salinity conditions there, and in other agricultural lands in the state. Mapping soil salinity at regional and state levels is essential for identifying drivers and trends in agricultural soil salinity, and for developing mitigation strategies, but traditional soil sampling for salinity does not allow for accurate large-scale mapping. We tested remote-sensing modeling to map root zone soil salinity for farmland in the WSJV. According to our map, 0.78 million acres are salt affected (i.e., ECe > 4 dS/m, which represents 45% of the mapped farmland; 30% of that acreage is strongly or extremely saline. Independent validations of the remote-sensing estimations indicated acceptable to excellent correspondences, except in areas of low salinity and high soil heterogeneity. Remote sensing is a viable tool for helping landowners make decisions about land use and also for helping water districts and state agencies develop salinity mitigation strategies.

  19. Application of wastewater with high organic load for saline-sodic soil reclamation focusing on soil purification ability

    OpenAIRE

    M.A. Kameli; M. Chorom; N. Jaafarzadeh; H. Janadeleh

    2017-01-01

    Fresh water source scarcity in arid and semiarid area is limitation factor for saline-sodic soil reclamation. The reusing of agricultural drainage and industrial wastewater are preferred strategies for combating with this concern. The objective of current study was evaluation in application of industrial sugar manufacture wastewater due to high soluble organic compounds in saline-sodic and sodic soil. Also soil ability in wastewater organic compounds removal was second aim of present study. S...

  20. Remote Sensing Soil Salinity Map for the San Joaquin Vally, California

    Science.gov (United States)

    Scudiero, E.; Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.

    2015-12-01

    Soil salinization is a major natural hazard to worldwide agriculture. We present a remote imagery approach that maps salinity within a range (i.e., salinities less than 20 dS m-1, when measured as the electrical conductivity of the soil saturation extract), accuracy, and resolution most relevant to agriculture. A case study is presented for the western San Joaquin Valley (WSJV), California, USA (~870,000 ha of farmland) using multi-year Landsat 7 ETM+ canopy reflectance and the Canopy Response Salinity Index (CRSI). Highly detailed salinity maps for 22 fields (542 ha) established from apparent soil electrical conductivity directed sampling were used as ground-truth (sampled in 2013), totaling over 5000 pixels (30×30 m) with salinity values in the range of 0 to 35.2 dS m-1. Multi-year maximum values of CRSI were used to model soil salinity. In addition, soil type, elevation, meteorological data, and crop type were evaluated as covariates. The fitted model (R2=0.73) was validated: i) with a spatial k-folds (i.e., leave-one-field-out) cross-validation (R2=0.61), ii) versus salinity data from three independent fields (sampled in 2013 and 2014), and iii) by determining the accuracy of the qualitative classification of white crusted land as extremely-saline soils. The effect of land use change is evaluated over 2396 ha in the Broadview Water District from a comparison of salinity mapped in 1991 with salinity predicted in 2013 from the fitted model. From 1991 to 2013 salinity increased significantly over the selected study site, bringing attention to potential negative effects on soil quality of shifting from irrigated agriculture to fallow-land. This is cause for concern since over the 3 years of California's drought (2010-2013) the fallow land in the WSJV increased from 12.7% to 21.6%, due to drastic reduction in water allocations to farmers.

  1. Relationships between groundwater, surface water, and soil salinity in Polder 32, Southwest Bangladesh

    Science.gov (United States)

    Fry, D. C.; Ayers, J. C.

    2014-12-01

    In the coastal areas of Southwest Bangladesh polders are surrounded by tidal channels filled with brackish water. In the wet season, farmers create openings in the embankments to irrigate rice paddies. In the dry season, farmers do the same to create saline shrimp ponds. Residents on Polder 32, located within the Ganges-Brahmaputra-Meghna delta system, practice these seasonal farming techniques. Soils in the area are entisols, being sediment recently deposited, and contain mostly silt-sized particles. Brackish water in brine shrimp ponds may deposit salt in the soil, causing soil salinization. However, saline connate groundwater could also be contributing to soil salinization. Groundwater, surface water (fresh water pond, rice paddy and tidal channel water) and soil samples have been analyzed via inductively coupled plasma optical emission spectroscopy, inductively coupled plasma mass spectroscopy and ion chromatography in an attempt to correlate salinity measurements with each other in order to determine major sources of soil salinity. Multiple parameters, including distances of samples from tidal channels, inland streams, shrimp ponds and tube wells were measured to see if spatial correlations exist. Similarly, values from wet and dry seasons were compared to quantify temporal variations. Salt content in many soil samples were found to be high enough to significantly decrease rice yields. Continued soil salinization can decrease these yields even more, leading to farmers not producing enough food to sustain their families.

  2. The effect of biofertilizer fungi on Ciherang rice growth at some level of soil salinity

    OpenAIRE

    Y.B. SUBOWO

    2014-01-01

    A research about the effect of fungus contained biofertilizer on Ciherang rice that was growth on different level of soil salinity was conducted. One of the effect of global climate changes is the increase of sea water level. It leads to the expansion of sea water submerged land for agriculture. Salt intrution to the agriculture area considerably decrease soil fertility because of the high salinity. Some of microbes especially soil fungi such as Aspergillus sp and Penicillium sp. are able...

  3. [Research on remote sensing monitoring of soil salinization based on measured hyperspectral and EM38 data].

    Science.gov (United States)

    Yao, Yuan; Ding, Jian-Li; Kelimul, Ardak; Zhang, Fang; Lei, Lei

    2013-07-01

    In the present study, the delta oasis between the Weigan River and the Kuqa River was selected as our study area. Firstly, the measured hyperspectral data related to different soil salinization extent was combined with electromagnetic induction instrument (EM38) in order to establish a soil salinization monitoring model; Secondly, by using the scaling transformation method, the model was adopted to calibrate the soil salinity index calculated from Landsat-TM images. Thirdly, the calibrated Landsat-TM images were used for the retrieval of regional soil salinity, and the retrieved data was verified based on the measured data. We found that at wavelengths of 456, 533, 686 and 1 373 nm, the interpretated data of EM38 were highly correlated with soil spectral reflectance (obtained via first order differentiation transformation of the spectra). Additionally, the soil salinity index model constructed from the combination of 456, 686 and 1 373 nm waveband was the best model among the different saliniza tion monitoring models. The authors' conclusion is that with R2 = 0.799 3 (p salinity information at regional scale by combining the electromagnetic and multispectral data performed better than those monitoring models with only salinity index extracted from multispectral remote sensing method (R2 = 0.587 4, p salinization.

  4. Effect of Different Alternate Irrigation Strategies using Saline and Non-Saline Water on Corn Yield, Salinity and Moisture Distribution in Soil Profile

    Directory of Open Access Journals (Sweden)

    Ali Reza Kiani

    2017-01-01

    Full Text Available Introduction: Lack of water and deterioration in the quality of soil and water resources are considered to be the prime cause of reduced crop yield in arid and semi-arid regions ‘More crop per drop’ by trickle irrigation, deficit irrigation, and uncommon water are the best strategies for mitigating water crises. Different irrigation management strategies are needed to increase production in different areas. In areas where sufficient water is available, a full irrigation strategy could be a suitable option, while in areas where water is limited, deficit irrigation would be an appropriate method, and finally in areas where water resources are saline, management strategies for achieving sustainable production as well as economic yields would be suitable. Maize is the third most important grain crop in the world following wheat and rice and it is the main source of nutrition for humans and animals. Because of the importance of maize in the world, increasing maize production under environmental stresses is a big challenge for agricultural scientists. Different methods of irrigation and the use of saline water that had satisfactory results for increasing agricultural production have been studied by several investigators . The main objective of this study was to establish an efficient use of limited water resources as well as to explore the possibility of replacing saline water with fresh water using different management techniques. Materials and Methods: A field experiment was conducted over two maize cropping seasons (2012–2013 in northern Iran (Gorgan Agricultural Research Station to compare different alternate irrigation scenarios using saline water on corn yield, salinity and soil moisture distribution in a randomized complete block design with three replications. Treatments were: T1 and T2 = 100 and 50 % of crop water requirement with non-saline water, respectively; T3 and T4 = variable and fixed full irrigation with saline and non-saline

  5. Assessment of soil salinity problems in agricultural areas through spatial and temporal remote sensing

    Science.gov (United States)

    Abd-Elwahed, Mohammed Saifeldeen

    This study is aimed at addressing the capability of using remote sensing data in detecting and tracking soil salinization variability using a series of experimental methodologies. In a controlled experiment, the spectral reflectance changes associated with salt crust formation on soil surfaces were tracked in order to detect the optimum moisture levels for salinity detection and recognize the influence of soil texture on salinity-induced spectral changes. In another experiment, lettuce plants were utilized to assess plant biophysical responses to moderate salinity levels with canopy-level reflectance data. An FR-ASD spectrometer was used to collect reflectance data in the 400-2500 nm spectral region. Finally, MODIS satellite data were employed to analyze the temporal profiles of selected high (8-11 dS/m), moderate (4-6 dS/m) and none (1-3 dS/m), salt affected sites in the Nile Delta, Egypt. The analyses of spectral data revealed that the use of remote sensing data to discriminate salinity levels in soils is highly affected by moisture content and texture. At low moisture contents, salts have high reflectance in the VIS-NIR spectral region but low reflectance in SWIR region. Spectral ambiguity with soil salinity was found across soil texture types. Significant relationships were found between plant chlorophyll content and the REP index (R2 = 0.97), and dry biomass with SAVI values (R2 = 0.94) under different salinity treatments. The spectral vegetation indices (VI's), SAVI and REP, and water indices (WI's) were found to be effective in discriminating between plants growing under moderate conditions of soil salinity and a non-saline condition. The combination between VI's and WI's was found to be useful in improving the ability to assess salinity stressed plants from non-stressed plants. Finally, MODIS results showed separability between canopy seasonal growth under high saline (HS) and non-saline (NS) conditions based on phenology. Canopies growing under HS

  6. Biophysical properties as determinants for soil organic carbon and total nitrogen in grassland salinization.

    Science.gov (United States)

    Pan, Chengchen; Zhao, Halin; Zhao, Xueyong; Han, Huibang; Wang, Yan; Li, Jin

    2013-01-01

    Grassland salinization causes considerable changes to soil and vegetation, which can lead to changes in soil organic carbon (C) and total nitrogen (N). These changes have complex causal relationships. A significant correlation between soil organic C and total N and any soil or vegetation property does not necessarily imply a significant direct effect of the property on soil organic C and total N. In this study, a field survey was conducted to investigate the changes in soil organic C and total N in grassland along a salinity gradient in Hexi corridor, China, and the direct and indirect effects of soil and vegetation properties on both stocks were quantified using a path analysis approach. Significant decrease in soil organic C and total N contents were observed with increasing salinity. Both had significant positive correlations with the Normalized Difference Vegetation Index (NDVI), soil water, and fine particles (silt+clay) content (psoil EC, and sand content (pNDVI, fine particles content and soil water content had positive direct effects on soil organic C and total N stocks. Soil EC affected soil organic C and total N stocks mainly through its indirect negative effect on NDVI, soil texture, and water content. NDVI, soil texture, and moisture also indirectly affected soil organic C and total N stocks via changes in each other. These indirect effects augmented each other, although in some cases indirect effects worked in opposing directions.

  7. Influence of gypsum amendment on methane emission from paddy rice soil affected by saline irrigation water

    Directory of Open Access Journals (Sweden)

    Ei Ei eTheint

    2016-01-01

    Full Text Available To investigate the influence of gypsum application on methane (CH4 emission from paddy rice soil affected by saline irrigation water, two pot experiments with the rice cultivation were conducted. In pot experiment (I, salinity levels 30 mMNaCl (S30 and 90 mMNaCl (S90, that showed maximum and minimum CH4 production in an incubation experiment, respectively, were selected and studied without and with application of 1 Mg gypsum ha-1(G1. In pot experiment (II, CH4 emission was investigated under different rates of gypsum application: 1 (G1, 2.5 (G2.5 and 5 (G5 Mg gypsum ha-1 under a non-saline and saline condition of 25 mMNaCl (S25. In experiment (I, the smallest CH4 emission was observed in S90. Methane emission in S30 was not significantly different with the non-saline control. The addition of gypsum showed significant lower CH4 emission in saline and non-saline treatments compared with non-saline control. In experiment (II, the CH4 emissions in the saline treatments were not significantly different to the non-saline treatments except S25-G5. However, our work has shown that gypsum can lower CH4 emissions under saline and non-saline conditions. Thus, gypsum can be used as a CH4 mitigation option in non-saline as well as in saline conditions.

  8. Effects of Sludge Compost on EC value of Saline Soil and Plant Height of Medicago

    Science.gov (United States)

    Sun, Chongyang; Zhao, Ke; Chen, Xing; Wang, Xiaohui

    2017-12-01

    In this study, the effects of sludge composting on the EC value of saline soil and the response to Medicago plant height were studied by planting Medicago with pots for 45 days in different proportions as sludge composting with saline soil. The results showed that the EC value of saline soil did not change obviously with the increase of fertilization ratio,which indicated that the EC value of saline soil was close to that of the original soil. The EC decreased by 31.45% at fertilization ratio of 40%. The height of Medicago reached the highest at 40% fertilization ratio, and that was close to 60% fertilization ratio, and the difference was significant with other treatments. By comprehensive analyse and compare,the optimum application rate of sludge compost was 40% under this test condition.

  9. Application of wastewater with high organic load for saline-sodic soil reclamation focusing on soil purification ability

    Directory of Open Access Journals (Sweden)

    M.A. Kameli

    2017-04-01

    Full Text Available Fresh water source scarcity in arid and semiarid area is limitation factor for saline-sodic soil reclamation. The reusing of agricultural drainage and industrial wastewater are preferred strategies for combating with this concern. The objective of current study was evaluation in application of industrial sugar manufacture wastewater due to high soluble organic compounds in saline-sodic and sodic soil. Also soil ability in wastewater organic compounds removal was second aim of present study. Saline-sodic and sodic soil sample was leached in soil column by diluted wastewater of amirkabir sugar manufacture in Khuzestan Province of Iran at constant water head. Sodium, electric conductivity and chemical oxygen demand of soil column leachate were measured per each pore volume. The experimental kinetics of wastewater organic compounds on two saline-sodic and sodic soil were also investigated by three pseudo second order, intra particle diffusion and elovich model. The results of current study showed that electric conductivity of saline-sodic soil was decreased to 90% during 3 initial pore volumes, from other side exchangeable sodium percent of saline-sodic and sodic soil decreased 30 and 71 percent, respectively. There were no significant different between wastewater chemical oxygen demand removal by saline-sodic and sodic soil in both batch and column studies. Wastewater chemical oxygen demand was decreased to 35% during pass through soil column. The results showed that the adsorption kinetics of wastewater organic compounds were best fitted by the pseudo-second order model with 99 percent correlation coefficient (r2=0.99%.

  10. Landscape scale assessment of soil and water salinization processes in agricultural coastal area.

    Science.gov (United States)

    Elen Bless, Aplena; Follain, Stéphane; Coiln, François; Crabit, Armand

    2017-04-01

    Soil salinization is among main land degradation process around the globe. It reduces soil quality, disturbs soil function, and has harmful impacts on plant growth that would threaten agricultural sustainability, particularly in coastal areas where mostly susceptible on land degradation because of pressure from anthropogenic activities and at the same time need to preserve soil quality for supporting food production. In this presentation, we present a landscape scale analysis aiming to assess salinization process affecting wine production. This study was carried out at Serignan estuary delta in South of France (Languadoc Roussillon Region, 43˚ 28'N and 3˚ 31'E). It is a sedimentary basin near coastline of Mediterranean Sea. Field survey was design to characterize both space and time variability of soil and water salinity through water electrical conductivity (ECw) and soil 1/5 electrical conductivity (EC1/5). For water measurements, Orb River and groundwater salinity (piezometers) were determined and for soil 1737 samples were randomly collected from different soil depths (20, 50, 80, and 120 cm) between year 2012 and 2016 and measured. In order to connect with agricultural practices observations and interviews with farmers were conducted. We found that some areas combining specific criteria presents higher electrical conductivity: positions with lower elevation (a.s.l), Cambisols (Calcaric) / Fluvisols soil type (WRB) and dominated clay textures. These observations combined with geochemical determination and spatial analysis confirm our first hypothesis of sea salt intrusion as the main driven factor of soil salinity in this region. In this context, identification of salinization process, fine determination of pedological specificities and fine understanding of agricultural practices allowed us to proposed adaptation strategies to restore soil production function. Please fill in your abstract text. Key Words: Salinity, Coastal Agriculture, Landscape, Soil, Water

  11. Spatial analysis of soil salinity and soil structural stability in a semiarid region of New South Wales, Australia.

    Science.gov (United States)

    Odeh, Inakwu O A; Onus, Alex

    2008-08-01

    Salt-affected soils are a major threat to agriculture especially in the semiarid regions of the world. The effective management of these soils requires adequate understanding of not only how water and, hence, solutes are transported within the soil, but also how soil salinity and sodicity spatially interact to determine soil structural breakdown. For sustainable agricultural production, information on quantitative soil quality, such as salinity, is required for effective land management and environmental planning. In this study, quantitative methods for mapping indicators of soil structural stability, namely salinity and sodicity, were developed to assess the effect of these primary indicators on soil structural breakdown. The current levels of soil salinity, as measured by electrical conductivity (EC) of the soil/water suspension, soil sodicity, represented by exchangeable sodium percentage (ESP), and aggregate stability, were assessed. Remote sensing, geographical information system (GIS), and geostatistical techniques--primarily regression-kriging and indicator-kriging--were used to spatially predict the soil sodicity and salinity. The patterns of salinity (EC) and sodicity (ESP>5%) were identified. The effect of land use on these soil quality indicators was found to be minimal. Co-spatial patterns were elucidated between sodic soils (defined by ESP>5%) and highly probable mechanically dispersive soils predicted from indicator-kriging of ASWAT scores. It was established that the incorporation of EC with ESP into an objective index, called electrolyte stability index (ESI=ESP/EC), gave a good indication of soil dispersion, although the threshold ESI value below which effective structural breakdown might occur is 0.025, which is twice as small as the expected 0.05. The discrepancies between ESI and ASWAT scores suggest that other soil factors than salinity and sodicity are affecting soil structural breakdown. This calls for further investigation. The study

  12. Physiological and biochemical perspectives of non-salt tolerant plants during bacterial interaction against soil salinity.

    Science.gov (United States)

    Radhakrishnan, Ramalingam; Baek, Kwang Hyun

    2017-07-01

    Climatic changes on earth affect the soil quality of agricultural lands, especially by increasing salt deposition in soil, which results in soil salinity. Soil salinity is a major challenge to growth and reproduction among glycophytes (including all crop plants). Soil bacteria present in the rhizosphere and/or roots naturally protect plants from the adverse effects of soil salinity by reprogramming the stress-induced physiological changes in plants. Bacteria can enrich the soil with major nutrients (nitrogen, phosphorus, and potassium) in a form easily available to plants and prevent the transport of excess sodium to roots (exopolysaccharides secreted by bacteria bind with sodium ions) for maintaining ionic balance and water potential in cells. Salinity also affects plant growth regulators and suppresses seed germination and root and shoot growth. Bacterial secretion of indole-3-acetic acid and gibberellins compensates for the salt-induced hormonal decrease in plants, and bacterial 1-aminocyclopropane-1-carboxylate (ACC) deaminase synthesis decreases ethylene production to stimulate plant growth. Furthermore, bacteria modulate the redox state of salinity-affected plants by enhancing antioxidants and polyamines, which leads to increased photosynthetic efficiency. Bacteria-induced accumulation of compatible solutes in stressed plants regulates plant cellular activities and prevents salt stress damage. Plant-bacterial interaction reprograms the expression of salt stress-responsive genes and proteins in salinity-affected plants, resulting in a precise stress mitigation metabolism as a defense mechanism. Soil bacteria increase the fertility of soil and regulate the plant functions to prevent the salinity effects in glycophytes. This review explains the current understanding about the physiological changes induced in glycophytes during bacterial interaction to alleviate the adverse effects of soil salinity stress. Copyright © 2017 Elsevier Masson SAS. All rights

  13. Evaluation of soil and water salinity for irrigation in North-eastern ...

    African Journals Online (AJOL)

    GREG

    2013-05-08

    May 8, 2013 ... Poor irrigation agriculture in arid and semiarid regions results in land degradation through soil salinity and sodic soil developments in different parts of the world. Hence, the study of arid lands and salt affected soils has been an important topic for modern agricultural management and particularly for poor ...

  14. A meta-analysis of soil salinization effects on nitrogen pools, cycles and fluxes in coastal ecosystems.

    Science.gov (United States)

    Zhou, Minghua; Butterbach-Bahl, Klaus; Vereecken, Harry; Brüggemann, Nicolas

    2017-03-01

    Salinity intrusion caused by land subsidence resulting from increasing groundwater abstraction, decreasing river sediment loads and increasing sea level because of climate change has caused widespread soil salinization in coastal ecosystems. Soil salinization may greatly alter nitrogen (N) cycling in coastal ecosystems. However, a comprehensive understanding of the effects of soil salinization on ecosystem N pools, cycling processes and fluxes is not available for coastal ecosystems. Therefore, we compiled data from 551 observations from 21 peer-reviewed papers and conducted a meta-analysis of experimental soil salinization effects on 19 variables related to N pools, cycling processes and fluxes in coastal ecosystems. Our results showed that the effects of soil salinization varied across different ecosystem types and salinity levels. Soil salinization increased plant N content (18%), soil NH4(+) (12%) and soil total N (210%), although it decreased soil NO3(-) (2%) and soil microbial biomass N (74%). Increasing soil salinity stimulated soil N2 O fluxes as well as hydrological NH4(+) and NO2(-) fluxes more than threefold, although it decreased the hydrological dissolved organic nitrogen (DON) flux (59%). Soil salinization also increased the net N mineralization by 70%, although salinization effects were not observed on the net nitrification, denitrification and dissimilatory nitrate reduction to ammonium in this meta-analysis. Overall, this meta-analysis improves our understanding of the responses of ecosystem N cycling to soil salinization, identifies knowledge gaps and highlights the urgent need for studies on the effects of soil salinization on coastal agro-ecosystem and microbial N immobilization. Additional increases in knowledge are critical for designing sustainable adaptation measures to the predicted intrusion of salinity intrusion so that the productivity of coastal agro-ecosystems can be maintained or improved and the N losses and pollution of the natural

  15. Detection of terrain indices related to soil salinity and mapping salt-affected soils using remote sensing and geostatistical techniques.

    Science.gov (United States)

    Triki Fourati, Hela; Bouaziz, Moncef; Benzina, Mourad; Bouaziz, Samir

    2017-04-01

    Traditional surveying methods of soil properties over landscapes are dramatically cost and time-consuming. Thus, remote sensing is a proper choice for monitoring environmental problem. This research aims to study the effect of environmental factors on soil salinity and to map the spatial distribution of this salinity over the southern east part of Tunisia by means of remote sensing and geostatistical techniques. For this purpose, we used Advanced Spaceborne Thermal Emission and Reflection Radiometer data to depict geomorphological parameters: elevation, slope, plan curvature (PLC), profile curvature (PRC), and aspect. Pearson correlation between these parameters and soil electrical conductivity (EC soil ) showed that mainly slope and elevation affect the concentration of salt in soil. Moreover, spectral analysis illustrated the high potential of short-wave infrared (SWIR) bands to identify saline soils. To map soil salinity in southern Tunisia, ordinary kriging (OK), minimum distance (MD) classification, and simple regression (SR) were used. The findings showed that ordinary kriging technique provides the most reliable performances to identify and classify saline soils over the study area with a root mean square error of 1.83 and mean error of 0.018.

  16. Simulation of Salinity Distribution in Soil Under Drip Irrigation Tape with Saline Water Using SWAP Model

    Directory of Open Access Journals (Sweden)

    M. Tabei

    2016-02-01

    Full Text Available Introduction: The to be limited available water amount from one side and to be increased needs of world population from the other side have caused increase of cultivation for products. For this reason, employing new irrigation ways and using new water resources like using the uncommon water (salty water, water drainage are two main strategies for regulating water shortage conditions. On the other side, accumulation of salts on the soil surface in dry regions having low rainfall and much evaporation, i.e. an avoidable case. As doing experiment for determining moisture distribution form demands needs a lot of time and conducting desert experiments are costly, stimulator models are suitable alternatives in answering the problem concerning moving and saltiness distribution. Materials and Methods: In this research, simulation of soil saltiness under drip irrigation was done by the SWAP model and potency of the above model was done in comparison with evaluated relevant results. SWAP model was performed based on measured data in a corn field equipped with drip irrigation system in the farming year 1391-92 in the number one research field in the engineering faculty of water science, ShahidChamran university of Ahvaz and hydraulic parameters of soil obtained from RETC . Statistical model in the form of a random full base plan with four attendants for irrigating water saltiness including salinity S1 (Karoon River water with salinity 3 ds/m as a control treatment, S2 (S1 +0/5, S3 (S1 +1 and S4 (S1 +1/5 dS/m, in 3 repetition and in 3 intervals of 10 cm emitter, 20 cm emitters on the stack, at a depth of 0-90 cm (instead of each 30 cm from soil surface and intervals of 30, 60 and 90 days after modeling cultiviation was done. The cultivation way was done handheld in plots including four rows of 3 m in distance of 75 cm rows and with denseness of 80 bushes in a hectar. Drip irrigation system was of type strip with space of 20 cm pores. Results and Discussion

  17. The U.S. Salinity Laboratory (USDA-ARS) guidelines for assessing multi-scale soil salinity with proximal and remote sensing

    Science.gov (United States)

    Soil salinity is a major threat to sustainable agriculture, especially in arid and semi-arid regions. Updated and accurate inventories of salinity in agronomically and environmentally relevant ranges (i.e., <20 dS/m, when salinity is measured as electrical conductivity of the saturation extract, ECe...

  18. Effect of EM Bokashi application on control of secondary soil salinization

    Directory of Open Access Journals (Sweden)

    Shao Xiaohou

    2008-12-01

    Full Text Available In order to ameliorate saline-alkaline soil, EM Bokashi has been applied to rice production in conjunction with subdrainage in Ningxia Autonomous Region and Zhejiang Province. The preliminary results can be summarized as follows: EM Bokashi can increase soil organic matter content, improve soil porosity and permeability, and raise the soil's levels of available nutrients; and EM Bokashi combined with subdrainage treatment is more effective in controlling secondary soil salinization and raising the grain yield and quality than other treatments. The results suggest that EM Bokashi can reduce the necessary amount of chemical fertilizer application, thereby improving the agricultural environment, and that the introduction of EM Bokashi into systems of secondary soil salinization control systems has resulted in significant benefits.

  19. Using a trait-based approach to link microbial community composition and functioning to soil salinity

    Science.gov (United States)

    Rath, Kristin; Fierer, Noah; Rousk, Johannes

    2017-04-01

    Our knowledge of the dynamics structuring microbial communities and the consequences this has for soil functions is rudimentary. In particular, predictions of the response of microbial communities to environmental change and the implications for associated ecosystem processes remain elusive. Understanding how environmental factors structure microbial communities and regulate the functions they perform is key to a mechanistic understanding of how biogeochemical cycles respond to environmental change. Soil salinization is an agricultural problem in many parts of the world. The activity of soil microorganisms is reduced in saline soils compared to non-saline soil. However, soil salinity often co-varies with other factors, making it difficult to assign responses of microbial communities to direct effects of salinity. A trait-based approach allows us to connect the environmental factor salinity with the responses of microbial community composition and functioning. Salinity along a salinity gradient serves as a filter for the community trait distribution of salt tolerance, selecting for higher salt tolerance at more saline sites. This trait-environment relationship can be used to predict responses of microbial communities to environmental change. Our aims were to (i) use salinity along natural salinity gradients as an environmental filter, and (ii) link the resulting filtered trait-distributions of the communities (the trait being salt tolerance) to the community composition. Soil samples were obtained from two replicated salinity gradients along an Australian salt lake, spanning a wide range of soil salinities (0.1 dS m-1 to >50 dS m-1). In one of the two gradients salinity was correlated with pH. Community trait distributions for salt tolerance were assessed by establishing dose-dependences for extracted bacterial communities using growth rate assays. In addition, functional parameters were measured along the salt gradients. Community composition of sites was compared

  20. Soil Salinity Controls on Water and Carbon Cycling by Sunflower Plants

    Science.gov (United States)

    Runkle, B.; Liang, X.; Dracup, J.; Hao, F.; Zeng, A.; Zhang, J.; He, B.; Oki, T.

    2007-12-01

    Agricultural effects on water cycling are of great importance for regional water resources management. These effects vary based on local soil and climate conditions, and are particularly modulated by high soil salinity levels, which stress plant growth and change their water use efficiency. Increasing salinization is predicted under hotter, drier conditions resulting from global climate change and from increased societal pressure on agricultural lands. This increased ionic presence creates a higher soil osmotic pressure that increases the resistance to water flow through the plant. This change also impacts the assimilation of carbon dioxide through the stomatal opening, and so affects rates of both photosynthesis and transpiration. Current agricultural and land-surface models that account for salinity do so in an overly empirical manner that cannot account for changes at different time scales in meteorological conditions. They tend to be ill equipped to examine how changing carbon dioxide levels may modify a plant's response to soil salinity. As a result, we present a new model of soil-vegetation- atmosphere water transfer that explicitly incorporates the role of soil salinity in changing this system's behavior. This model will allow for much greater flexibility in examining how vegetation may change the local water cycle under the joint impacts of both salinity and climate change. This model is supported by field research on the effects of salinity on sunflower plants in a large irrigation district in Inner Mongolia, China. Results presented include the role of salinity in changing stomatal regulation of water use efficiency, sub-canopy changes in leaf pressure, and changes in root activity. Modeling at sub-hourly time scales allows for a more precise understanding of how soil salinity changes the diurnal cycle of plant water use.

  1. Studies on Non-Symbiotic Diazotrophic Bacterial Populations of Coastal Arable Saline Soils of India

    National Research Council Canada - National Science Library

    Barua, Shilajit; Tripathi, Sudipta; Chakraborty, Ashis; Ghosh, Sagarmoy; Chakrabarti, Kalyan

    2011-01-01

    The effect of fluctuations of salinity in three different seasons on diazotrophic populations and N2 fixation in six mono cropped rice field soils of the coastal region of the Gangetic delta of West...

  2. Seed priming and sulfur effects on soybean cell membrane stability and yield in saline soil

    National Research Council Canada - National Science Library

    Bejandi, Teymur Khandan; Sedghi, Mohammad; Sharifi, Raouf Seyed; Namvar, Ali; Molaei, Peyman

    2009-01-01

    The objective of this work was to determine the effects of seed priming and sulfur application on cell membrane characteristics, seedling emergence, chlorophyll content and grain yield of soybean (Glycine max) in saline soil...

  3. Geostatistical monitoring of soil salinity in Uzbekistan by repeated EMI surveys

    NARCIS (Netherlands)

    Akramkhanov, A.; Brus, D.J.; Walvoort, D.J.J.

    2014-01-01

    Soil salinization in the lower reaches of Amudarya is a constant threat High seepage losses in irrigation water delivery network and deteriorated drainage network result in rising groundwater tables. The shallow groundwater table contributes to salinization of the rooting zone which is tackled by

  4. Microbial community biomass and structure in saline and non-saline soils associated with salt, boron tolerant poplar clones grown for the phytoremediation of selenium.

    Science.gov (United States)

    Dangi, Sadikshya R; Bañuelos, Gary; Buyer, Jeffrey S; Hanson, Bradley; Gerik, James

    2017-07-05

    Poplar trees (Populus spp.) are often used in bioremediation strategies because of their ability to phytoextract potential toxic ions, e.g., selenium (Se) from poor quality soils. Soil microorganisms may play a vital role in sustaining health of soil and/or tolerance of these trees grown in poor quality soils by contributing to nutrient cycling, soil structure, overall soil quality and plant survival. The effect of naturally-occurring salts, boron (B) and Se on soil microbial community composition associated with poplar trees is not known for bioremediation strategies. In this study, three Populus clones: 13-366, 345-1, and 347-14 were grown in spring 2006 under highly saline, B and Se clay-like soils in the west side of the San Joaquin Valley (SJV) of CA, as well as in non-saline sandy loam soils located in the east side of the SJV. After 7 years of growing in the respective soils of different quality, soil samples were collected from poplar clones grown in saline and non-saline soils to examine and compare soil quality effects on soil microbial community biomass and composition. Phospholipid fatty acid (PLFA) analysis was used to characterize microbial community composition in soils from trees grown at both locations. This study showed that microbial biomass as well as the amount and proportion of arbuscular mycorrhizal fungal (AMF) community were lower in all three poplar clones grown in saline soil compared to non-saline soil. Amounts of Gram + bacterial and actinomycetes PLFAs were significantly lower in poplar clone 13-366 grown in saline soil compared to non-saline soil; however, they did not differ significantly in poplar clones 347-14 and 345-1. Additionally, amounts of saprophytic fungal, Gram - bacterial and eukaryotic PLFA remained similar at saline and non-saline sites under poplar clones 347-14, 345-1 and 13-366. Therefore, this study suggested that salinity and B do have an impact on microbial biomass and AMF, however, these poplar clones still

  5. Infrared thermal remote sensing for soil salinity assessment on landscape scale

    Science.gov (United States)

    Ivushkin, Konstantin; Bartholomeus, Harm; Bregt, Arnold K.; Pulatov, Alim; Bui, Elisabeth N.; Wilford, John

    2017-04-01

    Soil salinity is considered as one of the most severe land degradation aspects. An increased soil salt level inhibits growth and development of crops. Therefore, up to date soil salinity information is vital for appropriate management practices and reclamation strategies. This information is required at increasing spatial and temporal resolution for appropriate management adaptations. Conventional soil sampling and associated laboratory analyses are slow, expensive, and often cannot deliver the temporal and spatial resolution required. The change of canopy temperature is one of the stress indicators in plants. Its behaviour in response to salt stress on individual plant level is well studied in laboratory and greenhouse experiments, but its potential for landscape scale studies using remote sensing techniques is not investigated yet. In our study, possibilities of satellite thermography for landscape scale soil salinity assessment of cropped areas were studied. The performance of satellite thermography is compared with other approaches that have been used before, like Normalised Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). The study areas were Syrdarya province of Uzbekistan and four study areas in four Australian states namely, Western Australia, South Australia, Queensland and New South Wales. The diversity of the study areas allowed us to analyse behaviour of canopy temperature of different crops (wheat, cotton, barley) and different agriculture practices (rain fed and irrigated). MODIS and Landsat TM multiannual satellite images were used to measure canopy temperature. As ground truth for Uzbekistan study area we used a provincial soil salinity map. For the Australian study areas we used the EC map for the whole country. ANOVA was used to analyse relations between the soil salinity maps and canopy temperature, NDVI, EVI. Time series graphs were created to analyse the dynamics of the indicators during the growing season. The results

  6. Effect on Soil Properties of BcWRKY1 Transgenic Maize with Enhanced Salinity Tolerance

    Directory of Open Access Journals (Sweden)

    Xing Zeng

    2016-01-01

    Full Text Available Maize (Zea mays L. is the most important cereal crop in the world. However, soil salinity has become a major problem affecting plant productivity due to arable field degradation. Thus, transgenic maize transformed with a salinity tolerance gene has been developed to further evaluate its salt tolerance and effects on agronomic traits. It is necessary to analyze the potential environmental risk of transgenic maize before further commercialization. Enzyme activities, physicochemical properties, and microbial populations were evaluated in saline and nonsaline rhizosphere soils from a transgenic maize line (WL-73 overexpressing BcWRKY1 and from wild-type (WT maize LH1037. Measurements were taken at four growth stages (V3, V9, R1, and R6 and repeated in three consecutive years (2012–2014. There was no change in the rhizosphere soils of either WL-73 or WT plants in the four soil enzyme activities, seven soil physicochemical properties, and the populations of three soil organisms. The results of this study suggested that salinity tolerant transgenic maize had no adverse impact on soil properties in soil rhizosphere during three consecutive years at two different locations and provided a theoretical basis for environmental impact monitoring of salinity tolerant transgenic maize.

  7. Effectiveness of T. harzianum and Humate Amendment in Soil Salinity Restoration

    Science.gov (United States)

    Apostolakis, Antonios; Daliakopoulos, Ioannis; Tsanis, Ioannis

    2017-04-01

    Soil salinity is a major soil degradation threat, especially for the water stressed parts of the Mediterranean region, where it hinders soil fertility and thus agricultural productivity. Soil salinity management can be complex and expensive, often resorting to the use of chemical amendments thus risking soil and aquifer pollution. This study quantifies the beneficial effects of (a) a commercial strain of the beneficial fungus Trichoderma harzianum (TH), and (b) a commercial humate fertilizer enhancer (HFE) approved for organic farming, against soil salinization. The treatments are tested in the context of a Solanum lycopersicum (tomato) greenhouse simulation of the cultivation conditions typical for the semi-arid coastal Timpaki basin in south-central Crete. 20 vigorous 20-day-old Solanum lycopersicum L. cv Elpida seedlings are treated either with TH or HFE, using soil substrates and irrigation treatments of two degradation states. 20 additional plants serve either as controls or guard rows. All plants are transplanted into 35 L pots under greenhouse conditions. Preliminary analysis of soil salinity and crop yield indicators suggest that both treatments are beneficial for the soil-plant system, each to a different extent depending on initial soil conditions.

  8. A Novel Bias Correction Method for Soil Moisture and Ocean Salinity (SMOS Soil Moisture: Retrieval Ensembles

    Directory of Open Access Journals (Sweden)

    Ju Hyoung Lee

    2015-12-01

    Full Text Available Bias correction is a very important pre-processing step in satellite data assimilation analysis, as data assimilation itself cannot circumvent satellite biases. We introduce a retrieval algorithm-specific and spatially heterogeneous Instantaneous Field of View (IFOV bias correction method for Soil Moisture and Ocean Salinity (SMOS soil moisture. To the best of our knowledge, this is the first paper to present the probabilistic presentation of SMOS soil moisture using retrieval ensembles. We illustrate that retrieval ensembles effectively mitigated the overestimation problem of SMOS soil moisture arising from brightness temperature errors over West Africa in a computationally efficient way (ensemble size: 12, no time-integration. In contrast, the existing method of Cumulative Distribution Function (CDF matching considerably increased the SMOS biases, due to the limitations of relying on the imperfect reference data. From the validation at two semi-arid sites, Benin (moderately wet and vegetated area and Niger (dry and sandy bare soils, it was shown that the SMOS errors arising from rain and vegetation attenuation were appropriately corrected by ensemble approaches. In Benin, the Root Mean Square Errors (RMSEs decreased from 0.1248 m3/m3 for CDF matching to 0.0678 m3/m3 for the proposed ensemble approach. In Niger, the RMSEs decreased from 0.14 m3/m3 for CDF matching to 0.045 m3/m3 for the ensemble approach.

  9. Dynamic of Saline Soil Cations after NaCl Application on Rice Growth and Yields

    Directory of Open Access Journals (Sweden)

    Wanti Mindari

    2013-09-01

    Full Text Available Saline soil cation dynamic is determined by the proportion of salt cations dissolved either acidic or alkaline. Common base cations in saline soil are in the proportion of Na > Ca > Mg > K. They affects the availability of water, nutrients, and plant growth. The six level of NaCl were 0, 15, 30, 45, 60, and 75 mM and two types of soil (saline and non saline from Gununganyar and Mojokerto were evaluated to soil sample cations taken from depth of 0-5, 5-10, 10-15, and 15-20 cm. Rice growth and yields were measured. The experiment indicated that increasing doses of NaCl increased the soil Na after rice harvest and decreased K, Ca and Mg contents, both of non-saline and saline soil, decreased of rice growth and yield (straw, grain, number of tiller. NaCl up to 30 mM caused highest Ca:Mg ratio, about 8, suppressed nutrient available, inhibited root growth and reduced nutrient uptake.

  10. [Relationships between typical vegetations, soil salinity, and groundwater depth in the Yellow River Delta of China].

    Science.gov (United States)

    Ma, Yu-Lei; Wang, De; Liu, Jun-Min; Wen, Xiao-Hu; Gao, Meng; Shao, Hong-Bo

    2013-09-01

    Soil salinity and groundwater depth are the two important factors affecting the vegetation growth and distribution in the Yellow River Delta. Through field investigation and statistical analysis, this paper studied the relationships between the typical vegetations (Suaeda heteroptera-Tamarix chinensis, Robinia pseudoacacia, Phragmites australis, and cotton) , soil salinity, and groundwater depth in the Delta. In the study area, groundwater depth had significant effects on soil salinity, with the average influence coefficient being 0.327. When the groundwater depth was 0.5-1.5 m, soil salinization was most severe. The vegetation growth in the Delta was poorer, with the NDVI in 78% of the total area being less than 0.4. Groundwater depth and soil salinity had significant effects on the vegetation distribution. Soil salinity had significant effects on the NDVI of R. pseudoacacia, S. heteroptera-T. chinensis, P. australis, and cotton, while groundwater depth had significant effects on the NDVI of S. heteroptera - T. chinensis, but lesser effects on the NDVI of P. australis, cotton and R. pseudoacacia.

  11. Assessing Soil Salinity with the use of WorldView-2 Hyperspectral Images in Timpaki, Crete

    Science.gov (United States)

    Alexakis, Dimitrios D.; Daliakopoulos, Ioannis N.; Panagea, Ioanna S.; Tsanis, Ioannis K.

    2016-04-01

    Salinization is one of the major soil degradation threats occurring worldwide, with its effects being observed in numerous vital ecological and non-ecological soil functions. Traditionally, soil salinity is assessed by laboratory determination of the soil electrical conductivity (ECe), rendering large scale studies labor and cost intensive. This study evaluates the feasibility of surface soil salinity estimation, monitoring, and mapping based on images acquired by the WorldView-2 and Landsat 8 multispectral sensors after calibration with a limited number of soil samples. A range of satellite image processing techniques are applied, starting with geometric, radiometric and atmospheric preprocessing corrections. More than 10 spectral salinity indices (algebric equations between visible and infrared band) including three newly introduced salinity indices, as well as vegetation indices (NDVI, SAVI, etc.) are implemented to detect surface salt deposition and vegetation health. Spectral unmixing is used to monitor salinity employing sophisticated classification approaches. Principal Component Analysis (PCA) is applied to a WorldView-2 images in order to determine the initial axes used for the orthogonal transformation, followed by a subsequent 3D rotation of the PCA axes. The linear coefficients of the transformation are retrieved and adjusted to detect salinity in all the range of WorldView-2 image. Furthermore, Landsat 8 images are used to establish and compare the diachronic vegetation regime and plant health in both brackish irrigation and salinity-free olive groves areas. The proposed methods are tested in the RECARE FP7 Project Case Study of Timpaki, a coastal semi-arid region in south-central Crete. Long term agricultural over-exploitation in the area and little irrigation alternatives have led to seawater intrusion and in turn to soil salinization. EO products are calibrated using soil samples collected from bare soil plots at 0-5 cm depth and representing a

  12. Soil salinity under deficit drip irrigation of potato and millet in in an arid environment

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2017-06-01

    Full Text Available The influence of deficit irrigation (DI with saline water on soil salinity in a drip-irrigated potato and millet fields was investigated. We had compared proportional soil salinity developed under Full and DI under drip irrigation. For both experiments, the treatments were (1 Full, control treatment where rooting zone soil water content was increased to field capacity at each irrigation; (2 DI80; (3 DI60 and DI40; 20, 40 and 60% deficit irrigation compared to Full treatment were applied, respectively. Soil salinity was assessed using the isosalinity maps constructed with grid soil sampling of plant root zone at harvest. Results show that high spatial variability was observed in salinity along soil profiles when applying saline water with drip irrigation for potato. For the DI40 and DI60 treatments, high soil salinity was recorded in the upper soil layer close to the emitter. Increase of soil salinity within soil depths of 30 cm or below was also observed under DI60 and DI40 treatments. The lowest increase was noted under the full treatment. Surface soil salinity was somewhat higher under DI60 and DI40 compared with that of full and DI80 irrigation treatments. The distribution of salts around the dripper changes during the crop season according to applied irrigation treatments, with overall higher concentrations between the drippers and towards the margin of wetted band. Iso-salinity maps at harvest of potato showed that the surface layer of 30 cm depth had the lowest salinity which gradually increased at deeper zones irrespective of the treatment. Salt accumulation essentially occurred at wetting front between the drippers and the plant row. Although salt accumulation was relatively highest along the row under DI treatments, the area of accumulation was relatively shifted toward the center between the rows and the drip line. The results also show the importance of the potato cropping season to benefit from the leaching of soluble salts with the

  13. Remote Sensing Monitoring of Changes in Soil Salinity: A Case Study in Inner Mongolia, China

    Directory of Open Access Journals (Sweden)

    Jingwei Wu

    2008-11-01

    Full Text Available This study used archived remote sensing images to depict the history of changes in soil salinity in the Hetao Irrigation District in Inner Mongolia, China, with the purpose of linking these changes with land and water management practices and to draw lessons for salinity control. Most data came from LANDSAT satellite images taken in 1973, 1977, 1988, 1991, 1996, 2001, and 2006. In these years salt-affected areas were detected using a normal supervised classification method. Corresponding cropped areas were detected from NVDI (Normalized Difference Vegetation Index values using an unsupervised method. Field samples and agricultural statistics were used to estimate the accuracy of the classification. Historical data concerning irrigation/drainage and the groundwater table were used to analyze the relation between changes in soil salinity and land and water management practices. Results showed that: (1 the overall accuracy of remote sensing in detecting soil salinity was 90.2%, and in detecting cropped area, 98%; (2 the installation/innovation of the drainage system did help to control salinity; and (3 a low ratio of cropped land helped control salinity in the Hetao Irrigation District. These findings suggest that remote sensing is a useful tool to detect soil salinity and has potential in evaluating and improving land and water management practices.

  14. High temperature and salinity enhance soil nitrogen mineralization in a tidal freshwater marsh.

    Directory of Open Access Journals (Sweden)

    Haifeng Gao

    Full Text Available Soil nitrogen (N mineralization in wetlands is sensitive to various environmental factors. To compare the effects of salinity and temperature on N mineralization, wetland soils from a tidal freshwater marsh locating in the Yellow River Delta was incubated over a 48-d anaerobic incubation period under four salinity concentrations (0, 10, 20 and 35‰ and four temperature levels (10, 20, 30 and 40°C. The results suggested that accumulated ammonium nitrogen (NH4+-N increased with increasing incubation time under all salinity concentrations. Higher temperatures and salinities significantly enhanced soil N mineralization except for a short-term (≈10 days inhibiting effect found under 35‰ salinity. The incubation time, temperature, salinity and their interactions exhibited significant effects on N mineralization (P0.05, while temperature exhibited the greatest effect (P<0.001. Meanwhile, N mineralization processes were simulated using both an effective accumulated temperature model and a one-pool model. Both models fit well with the simulation of soil N mineralization process in the coastal freshwater wetlands under a range of 30 to 40°C (R2 = 0.88-0.99, P<0.01. Our results indicated that an enhanced NH4+-N release with increasing temperature and salinity deriving from the projected global warming could have profound effects on nutrient cycling in coastal wetland ecosystems.

  15. Leveraging Machine Learning to Estimate Soil Salinity through Satellite-Based Remote Sensing

    Science.gov (United States)

    Welle, P.; Ravanbakhsh, S.; Póczos, B.; Mauter, M.

    2016-12-01

    Human-induced salinization of agricultural soils is a growing problem which now affects an estimated 76 million hectares and causes billions of dollars of lost agricultural revenues annually. While there are indications that soil salinization is increasing in extent, current assessments of global salinity levels are outdated and rely heavily on expert opinion due to the prohibitive cost of a worldwide sampling campaign. A more practical alternative to field sampling may be earth observation through remote sensing, which takes advantage of the distinct spectral signature of salts in order to estimate soil conductivity. Recent efforts to map salinity using remote sensing have been met with limited success due to tractability issues of managing the computational load associated with large amounts of satellite data. In this study, we use Google Earth Engine to create composite satellite soil datasets, which combine data from multiple sources and sensors. These composite datasets contain pixel-level surface reflectance values for dates in which the algorithm is most confident that the surface contains bare soil. We leverage the detailed soil maps created and updated by the United States Geological Survey as label data and apply machine learning regression techniques such as Gaussian processes to learn a smooth mapping from surface reflection to noisy estimates of salinity. We also explore a semi-supervised approach using deep generative convolutional networks to leverage the abundance of unlabeled satellite images in producing better estimates for salinity values where we have relatively fewer measurements across the globe. The general method results in two significant contributions: (1) an algorithm that can be used to predict levels of soil salinity in regions without detailed soil maps and (2) a general framework that serves as an example for how remote sensing can be paired with extensive label data to generate methods for prediction of physical phenomenon.

  16. Cation dynamics in soils with different salinity levels growing irrigated rice

    Directory of Open Access Journals (Sweden)

    Felipe de Campos Carmona

    2010-12-01

    Full Text Available Salinity levels in soils of the Outer Coastal Plain of Rio Grande do Sul, Brazil, can be high, due to excess of Na in the irrigation water, evapotranspiration and soil development from marine sediments. The cultivation of irrigated rice could be an alternative, since ion uptake as well as leaching by the establishment of a water layer could mitigate the effects of soil salinity. This study aimed to evaluate the dynamics of basic cations in the solution of Albaqualf soils with different salinity levels growing irrigated rice. The plow layer contained exchangeable Na percentages (ESP of 5.6, 9.0, 21.2 and 32.7 %. The plant stand, dry matter, Na, K and Ca + Mg uptake at full flowering and grain yield were evaluated. The levels of Na, K, Ca + Mg and electrical conductivity (EC in the soil solution were also measured weekly during the rice cycle at four soil depths, in the water layer and irrigation water. The Na, K and Ca + Mg uptake by rice at full flowering was used to estimate ion depletion from the layer under root influence. Soil salinity induced a reduction in the rice stand, especially in the soil with ESP of 32.7 %, resulting in lower cation uptake and very low yield at that site. As observed in the water layer and irrigation water, the Na, K, Ca + Mg and EC levels in the soil solution decreased with time at depths of 5, 10 and 20 cm, regardless of the original soil salinity, showing that cation dynamics in the plow layer was determined by leaching and root uptake, rather than by the effect of evapoconcentration of basic cations in the soil surface layer.

  17. Multi-scale soil salinity mapping and monitoring with proximal and remote sensing

    Science.gov (United States)

    This talk is part of a technical short course on “Soil mapping and process modelling at diverse scales”. In the talk, guidelines, special considerations, protocols, and strengths and limitations are presented for characterizing spatial and temporal variation in soil salinity at several spatial scale...

  18. Soil and substrate testing to estimate nutrient availability and salinity status

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    In the greenhouse industry methods have been developed for the determination of the nutrient availability and salinity status of soils and substrates. As in other agriculture branches, soil testing has the aim to estimate the availability, including the solubility as well the quantity, of plant

  19. The Earthworm Eisenia fetida Can Help Desalinate a Coastal Saline Soil in Tianjin, North China

    Science.gov (United States)

    Zhang, Tao; Li, Suyan; Sun, Xiangyang; Zhang, Yang; Gong, Xiaoqiang; Fu, Ying; Jia, Liming

    2015-01-01

    A laboratory microcosm experiment was conducted to determine whether the earthworm Eisenia fetida could survive in a saline soil from a field site in North China, and an experiment using response surface methodology was conducted at that field site to quantify the effects of E. fetida and green waste compost (GWC) on the salt content of the soil. The microcosm results showed that E. fetida survived in GWC-amended saline soil and increased the contents of humic acid, available N, and available P in the GWC-amended soil. The data from the field experiment were described by the following second-order model:y^ =-1.76+0.091x1+0.48x2-0.00083x1x2-0.00078x12-0.022x22, where y is the decrease in soil salinity (g of salt per kg of dry soil) relative to the untreated control, x1 is the number of E. fetida added per m2, and x2 is the quantity of GWC added in kg per m2. The model predicted that the total salt content of the saline soil would decrease by > 2 g kg-1 (p.05) when 29–90 individuals m-2 of E. fetida and 6.1–15.0 kg m-2 of GWC were applied. We conclude that the use of E. fetida for soil desalination is promising and warrants additional investigation. PMID:26699869

  20. Salinity and soluble organic matter on virus sorption in sand and soil columns.

    Science.gov (United States)

    Cao, Haibo; Tsai, Frank T-C; Rusch, Kelly A

    2010-01-01

    The objective of this research was to study the sorption and transport of bacteriophage MS-2 (a bacterial virus) in saturated sediments under the effect of salinity and soluble organic matter (SOM). One-dimensional column experiments were conducted on washed high-purity silica sand and sandy soil. In sand column tests, increasing salinity showed distinct effect on enhancing MS-2 sorption. However, SOM decreased MS-2 sorption. Using a two-site reversible-irreversible sorption model and the double layer theory, we explained that pore-water salinity potentially compressed the theoretical thickness of double layers of MS-2 and sand, and thus increased sorption on reversible sorption sites. On irreversible sorption sites, increasing salinity reversed charges of some sand particles from negative to positive, and thus converted reversible sorption sites into irreversible sites and enhanced sorption of MS-2. SOM was able to expand the double layer thickness on reversible sites and competed with MS-2 for the same binding place on irreversible sites. In sandy soil column tests, the bonded and dissolved (natural) soil organic matters suppressed the effects of pore-water salinity and added SOM and significantly reduced MS-2 adsorption. This was explained that the bonded soil organic matter occupied a great portion of sorption sites and significantly reduced sorption sites for MS-2. In addition, the dissolved soil organic matter potentially expanded the double layer thickness of MS-2 and sandy soil on reversible sorption sites and competed with MS-2 for the same binding place.

  1. Jerusalem artichoke decreased salt content and increased diversity of bacterial communities in the rhizosphere soil in the coastal saline zone

    Science.gov (United States)

    Shao, Tianyun; Li, Niu; Cheng, Yongwen; Long, Xiaohua; Shao, Hongbo; Zed, Rengel

    2017-04-01

    Soil salinity is one of the main environmental constraints that restrict plant growth and agricultural productivity; however, utilization of salt-affected land can bring substantial benefits. This study used an in-situ remediation method by planting Jerusalem artichoke in naturally occurring saline alkali soils with different salinity (high salinity (H, >4.0 g•salt kg-1 soil), moderate salinity (M, 2.0-4.0 g•salt kg-1 soil) and low salinity (L, 1.0-2.0 g•salt kg-1 soil) in the coastal saline zone in southeast China in comparison with the respective controls without Jerusalem artichoke planting (undisturbed soil). Soil pH and salinity increased sequentially from the rhizosphere to the bulk soil and the unplanted controls. The activity of neutral phosphatase and invertase decreased in the order L > M > H, whereas that of catalase was reverse. The minimum content of calcite, muscovite and quartz, and maximum content of chlorite and albite, were found in the control soils. Planting of Jerusalem artichoke enhanced bacterial microflora in saline alkali soil. Proteobacteria, Acidobacteria, Actinobacteria and Bacteroidetes were the dominant phyla in all samples, accounting for more than 80% of the reads. The number of Operational Taxonomic Units (OTU) in the rhizosphere soil was, respectively, 1.27, 1.02 and 1.25 times higher compared with the bulk soil, suggesting that Jerusalem artichoke played a significant role in increasing abundance and diversity of soil microbial populations. The study showed that Jerusalem artichoke could be used to improve saline alkali soil by enriching bacterial communities, enhancing the activity of phosphatase and invertase, and decreasing soil salinity.

  2. Evaluation of TDR sensors to estimate moisture content in a highly saline soil from northern Chile

    Science.gov (United States)

    Cristi Matte, F.; Hernandez, M. F.; Fierro, V.; Hausner, M. B.; Munoz, J.; Suarez, F. I.

    2013-12-01

    The major component of the water budget in many of the volcanic basins located in northern Chile is evaporation from zones with shallow groundwater tables. Therefore, the water fluxes in the vadose zone in those dry volcanic-origin soils are of particular interest. In these soils, it has been reported that traditional time domain reflectometry (TDR) measurement methods are ineffective. TDR is a fast and nondestructive indirect electromagnetic method that is used to estimate soil moisture from the soil's apparent dielectric permittivity. The relationship between moisture content and apparent dielectric permittivity is influenced by many factors, such as length of the sensor's rods, salinity of porous media and soil mineralogy. In volcanic soils, it has been reported that Topp's 'universal' relationship is no longer valid. In this study, we evaluated the performance of TDR probes for the estimation of soil moisture in a highly saline and volcanic-origin soil from the Salar del Huasco basin, northern Chile. TDR sensors with rods of 7.5 and 30 cm were used to test the dielectric permittivity of different potassium chloride solutions of known permittivity (with electrical conductivity ranging from 0.015 to 12.9 dS/m). The TDR probes were then used to test the permittivity of soils at known water contents and temperatures. The effects of temperature and the salinity of the solutions on the apparent permittivity were negligible, and the shorter rods proved more accurate than the longer rods. Furthermore, neither the Topp's equation nor previously proposed relationships for volcanic-origin soils developed around the world were adequate to represent the soil's moisture content used in this study. Based on the results, we propose a new relationship between moisture content and apparent dielectric permittivity for the volcanic-origin soil of the Salar del Huasco basin. Further research is ongoing to obtain analogous relationships between moisture content and apparent

  3. Furfural and its biochar improve the general properties of a saline soil

    Science.gov (United States)

    Wu, Y.; Xu, G.; Shao, H. B.

    2014-07-01

    Organic materials (e.g., furfural residue) are generally believed to improve the physical and chemical properties of saline soils with low fertility. Recently, biochar has been received more attention as a possible measure to improve the carbon balance and improve soil quality in some degraded soils. However, little is known about their different amelioration of a sandy saline soil. In this study, 56 d incubation experiment was conducted to evaluate the influence of furfural and its biochar on the properties of saline soil. The results showed that both furfural and biochar greatly reduced pH, increased soil organic carbon (SOC) content and cation exchange capacity (CEC), and enhanced the available phosphorus (P) in the soil. Furfural is more efficient than biochar in reducing pH: 5% furfural lowered the soil pH by 0.5-0.8 (soil pH: 8.3-8.6), while 5% biochar decreased by 0.25-0.4 due to the loss of acidity in pyrolysis process. With respect to available P, furfural addition at a rate of 5% increased available P content by 4-6 times in comparison to 2-5 times with biochar application. In reducing soil exchangeable sodium percentage (ESP), biochar is slightly superior to furfural because soil ESP reduced by 51% and 43% with 5% furfural and 5% biochar at the end of incubation. In addition, no significant differences were observed between furfural and biochar about their capacity to retain N, P in leaching solution and to increase CEC in soil. These facts may be caused by the relatively short incubation time. In general, furfural and biochar exhibited a different effect depending on the property: furfural was more effective in decreasing pH and increasing available P, whereas biochar played a more important role in increasing SOC and reducing ESP of saline soil.

  4. Coastal Mudflat Saline Soil Amendment by Dairy Manure and Green Manuring

    OpenAIRE

    Bai, Yanchao; Yan, Yiyun; Zuo, Wengang; Gu, Chuanhui; Xue, Weijie; Mei, Lijuan; Shan, Yuhua; Feng, Ke

    2017-01-01

    Dairy manure or green manuring has been considered as popular organic amendment to cropland in many countries. However, whether dairy manure combined with green manuring can effectively amend mudflat saline soil remains unclear. This paper was one of first studies to fill this knowledge gap by investigating impact of dairy manure combined with green manuring on soil chemical properties of mudflat saline soil. Dairy manure was used by one-time input, with the rates of 0, 30, 75, 150, and 300 t...

  5. Remote Sensing of CO2 Absorption by Saline-Alkali Soils: Potentials and Constraints

    Directory of Open Access Journals (Sweden)

    Wenfeng Wang

    2014-01-01

    Full Text Available CO2 absorption by saline-alkali soils was recently demonstrated in the measurements of soil respiration fluxes in arid and semiarid ecosystems and hypothetically contributed to the long-thought “missing carbon sink.” This paper is aimed to develop the preliminary theory and methodology for the quantitative analysis of CO2 absorption by saline-alkali soils on regional and global scales. Both the technological progress of multispectral remote sensing over the past decades and the conjectures of mechanisms and controls of CO2 absorption by saline-alkali soils are advantageous for remote sensing of such absorption. At the end of this paper, the scheme for remote sensing is presented and some unresolved issues related to the scheme are also proposed for further investigations.

  6. Organic matter dynamics along a salinity gradient in Siberian steppe soils

    Science.gov (United States)

    Bischoff, Norbert; Mikutta, Robert; Shibistova, Olga; Dohrmann, Reiner; Herdtle, Daniel; Gerhard, Lukas; Fritzsche, Franziska; Puzanov, Alexander; Silanteva, Marina; Grebennikova, Anna; Guggenberger, Georg

    2018-01-01

    Salt-affected soils will become more frequent in the next decades as arid and semiarid ecosystems are predicted to expand as a result of climate change. Nevertheless, little is known about organic matter (OM) dynamics in these soils, though OM is crucial for soil fertility and represents an important carbon sink. We aimed at investigating OM dynamics along a salinity and sodicity gradient in the soils of the southwestern Siberian Kulunda steppe (Kastanozem, non-sodic Solonchak, Sodic Solonchak) by assessing the organic carbon (OC) stocks, the quantity and quality of particulate and mineral-associated OM in terms of non-cellulosic neutral sugar contents and carbon isotopes (δ13C, 14C activity), and the microbial community composition based on phospholipid fatty acid (PLFA) patterns. Aboveground biomass was measured as a proxy for plant growth and soil OC inputs. Our hypotheses were that (i) soil OC stocks decrease along the salinity gradient, (ii) the proportion and stability of particulate OM is larger in salt-affected Solonchaks compared to non-salt-affected Kastanozems, (iii) sodicity reduces the proportion and stability of mineral-associated OM, and (iv) the fungi : bacteria ratio is negatively correlated with salinity. Against our first hypothesis, OC stocks increased along the salinity gradient with the most pronounced differences between topsoils. In contrast to our second hypothesis, the proportion of particulate OM was unaffected by salinity, thereby accounting for only 90 %. Isotopic data (δ13C, 14C activity) and neutral sugars in the OM fractions indicated a comparable degree of OM transformation along the salinity gradient and that particulate OM was not more persistent under saline conditions. Our third hypothesis was also rejected, as Sodic Solonchaks contained more than twice as much mineral-bound OC than the Kastanozems, which we ascribe to the flocculation of OM and mineral components under higher ionic strength conditions. Contrary to the fourth

  7. Response of soil physicochemical properties and enzyme activities to long-term reclamation of coastal saline soil, Eastern China.

    Science.gov (United States)

    Xie, Xuefeng; Pu, Lijie; Wang, Qiqi; Zhu, Ming; Xu, Yan; Zhang, Meng

    2017-12-31

    Soil enzyme activity during different years of reclamation and land use patterns could indicate changes in soil quality. The objective of this research is to explore the dynamics of 5 soil enzyme activities (dehydrogenase, amylase, urease, acid phosphatase and alkaline phosphatase) involved in C, N, and P cycling and their responses to changes in soil physicochemical properties resulting from long-term reclamation of coastal saline soil. Soil samples from a total of 55 sites were collected from a coastal reclamation area with different years of reclamation (0, 7, 32, 40, 63a) in this study. The results showed that both long-term reclamation and land use patterns have significant effects on soil physicochemical properties and enzyme activities. Compared with the bare flat, soil water content, soil bulk density, pH and electrical conductivity showed a decreasing trend after reclamation, whereas soil organic carbon, total nitrogen and total phosphorus tended to increase. Dehydrogenase, amylase and acid phosphatase activities initially increased and then decreased with increasing years of reclamation, whereas urease and alkaline phosphatase activities were characterized by an increase-decrease-increase trend. Moreover, urease, acid phosphatase and alkaline phosphatase activities exhibited significant differences between coastal saline soil with 63years of reclamation and bare flat, whereas dehydrogenase and amylase activities remained unchanged. Aquaculture ponds showed higher soil water content, pH and EC but lower soil organic carbon, total nitrogen and total phosphorus than rapeseed, broad bean and wheat fields. Rapeseed, broad bean and wheat fields displayed higher urease and alkaline phosphatase activities and lower dehydrogenase, amylase and acid phosphatase activities compared with aquaculture ponds. Redundancy analysis revealed that the soil physicochemical properties explained 74.5% of the variation in soil enzyme activities and that an obvious relationship

  8. Research on screening of suitable forage grasses in coastal saline - alkaline soil

    Science.gov (United States)

    Yue, Xiaoyu; Han, Xin; Song, Qianhong; Yang, Xu; Zhou, Qingyun

    2017-11-01

    The screening of salt-tolerant plants can provide suitable tree species for the afforestation of coastal salinity and maintain biodiversity and ecological stability. The research was based on the study of seven grasses, such as high fescue, the bermuda grass, the thyme, the rye grass, the precocious grass, the third leaf, and the red three leaves. Each pasture was planted in three different kinds of soil, such as salt alkali soil, salt alkali soil + ecological bag and non-saline alkali soil. The effect of salt alkali soil on germinating time, germination rate and grass growth was analyzed. The effects of ecological bag on soil salt and the growth and germination of grass was also analyzed in order to provide the reference basis for the widespread and systematic selection of salt-tolerant plants, with the grass being selected for the suitable ecological bag.

  9. The side effects of nitrification inhibitors on leaching water and soil salinization in a field experiment

    Energy Technology Data Exchange (ETDEWEB)

    Diez, J. A.; Arauzo, M.; Hernaiz, P.; Sanz, A.

    2010-07-01

    In experiments carried out in greenhouses, some authors have shown that ammonium sulphate induces greater soil acidity and salinity than other sources of N. Moreover, nitrification inhibitors (NI) tend to cause ammonium to accumulate in soil by retarding its oxidation to nitrate. This accumulated ammonium would also have an effect on soil salinity. Consequently, the aim of this paper was to evaluate the soil and leaching water salinization effects associated with adding NI, dicyandiamide (DCD) and dimethylpyrazole-phosphate (DMPP) to ammonium sulphate nitrate (ASN) fertilizer. This experiment was carried out in the field with an irrigated maize crop. Drainage and Na concentration were measured during both seasons (2006 and 2007) and leached Na was determined. The treatments with NI (DCD and DMPP) were associated with greater Na concentrations in soil solutions and consequently higher rates of Na leaching (in 2007, ASN-DCD 1,292 kg Na ha{sup -}1, ASN-DMPP 1,019 kg Na ha{sup -}1). A treatment involving only ASN also increased the Na concentration in soil and the amount of Na leached in relation to the Control (in 2007, ASN 928 kg Na ha{sup -}1 and Control 587 kg Na ha{sup -}1). The increase in the ammonium concentration in the soil due to the NI treatments could have been the result of the displacement of Na ions from the soil exchange complex through a process which finally led to an increase in soil salinity. Treatments including ammonium fertilizer formulated with NI produced a greater degree of soil salinization due to the presence of ammonium from the fertilizer and accumulated ammonium from the nitrification inhibition. (Author) 31 refs.

  10. High Temperature and Salinity Enhance Soil Nitrogen Mineralization in a Tidal Freshwater Marsh

    Science.gov (United States)

    Gao, Haifeng; Bai, Junhong; He, Xinhua; Zhao, Qingqing; Lu, Qiongqiong; Wang, Junjing

    2014-01-01

    Soil nitrogen (N) mineralization in wetlands is sensitive to various environmental factors. To compare the effects of salinity and temperature on N mineralization, wetland soils from a tidal freshwater marsh locating in the Yellow River Delta was incubated over a 48-d anaerobic incubation period under four salinity concentrations (0, 10, 20 and 35‰) and four temperature levels (10, 20, 30 and 40°C). The results suggested that accumulated ammonium nitrogen (NH4+-N) increased with increasing incubation time under all salinity concentrations. Higher temperatures and salinities significantly enhanced soil N mineralization except for a short-term (≈10 days) inhibiting effect found under 35‰ salinity. The incubation time, temperature, salinity and their interactions exhibited significant effects on N mineralization (P0.05), while temperature exhibited the greatest effect (Pwetlands under a range of 30 to 40°C (R2 = 0.88–0.99, PNH4+-N release with increasing temperature and salinity deriving from the projected global warming could have profound effects on nutrient cycling in coastal wetland ecosystems. PMID:24733366

  11. Assessment of soil salinity in an agro-ecosystem under climate change in Western Siberia

    Science.gov (United States)

    Marciniak, Hasmik; Kiesel, Jens; Sheludkov, Artyom; Schmalz, Britta; Khoroshavin, Vitaly; Fohrer, Nicola

    2014-05-01

    Soil salinization, which can be a serious environmental problem, poses critical challenges for the management of agricultural and the status of natural areas. Strongly influenced by climate, topography, soil and land-use it requires sound adaptation strategies in order to cope with recent and future ecological changes and landscape transformation. Our studies on soil salinity were carried out in the Loktinka river basin with a catchment area of 334 km2. The Loktinka is a slow moving, meandering lowland river, passing along the south-eastern part of an agricultural zone of Tyumen region, nearby the town of Ishim. The Loktinka river, with 25 km in length, is a left tributary of the River Ishim which originates in a relatively small wetland, flows east and terminates in Lake Mergen. The area is representative for the southern part of the forest steppe zone with less favourable conditions for agriculture due to low soil qualities and salinization problems. The area is highly influenced by climate change. Reduced rainfall and increased evapotranspiration can intensify the salinity problem in the catchment and thus, there is a strong need for present and future research. A field program was designed in order to assess the current situation of soils within the catchment area in terms of salinity. Soil profiles and soil texture were identified and soil electrical conductivity as well as pH were measured. The electrical conductivity of horizons ranged from 78 to 1742 μScm-1. The soils were alkaline in reaction (pH 7.1 to 9.47), irrespective of depth. The texture was mainly clay loam. For the prediction of long-term hydro-salinity under climate change, the agro-hydro-salinity model SaltMod (Oosterbaan et al., 2008) was chosen. The model is based on seasonal water balances of agricultural lands for prediction of future trends made on a seasonal basis. Salinity in the soils column is simulated with SaltMod on different soil type and crop combinations.

  12. Effects of spatiotemporal variation of soil salinity on fine root distribution in different plant configuration modes in new reclamation coastal saline field.

    Science.gov (United States)

    Jiang, Hong; Du, Hongyu; Bai, Yingying; Hu, Yue; Rao, Yingfu; Chen, Chong; Cai, Yongli

    2016-04-01

    In order to study the effects of salinity on plant fine roots, we considered three different plant configuration modes (tree stand model (TSM), shrub stand model (SSM), and tree-shrub stand model (TSSM)). Soil samples were collected with the method of soil drilling. Significant differences of electrical conductivity (EC) in the soil depth of 0-60 cm were observed among the three modes (p salinity among various soil layers and monthly variation of soil salinity were the highest in SSM and reached 2.30 and 2.23 mS/cm (EC1:5), respectively. Due to the effect of salinity, fine root biomass (FRB) showed significant differences in different soil depths (p salinity should be below 1.5 mS/cm, which was suitable for the growth of plant roots. Among the three modes, TSSM had the highest FRB, SRL, and FRLD and no obvious soil salt accumulation was observed. The results indicated that fine root biomass was affected by high salt and that TSSM had the strong effects of salt suppression and control. In our study, TSSM may be the optimal configuration mode for salt suppression and control in saline soil.

  13. Determine the Efficacy of Salinity on Bioremediation of Polluted Soil by Phenanthrene

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    Masoumeh Ravanipour

    2011-04-01

    Full Text Available Background: Phenanthrene is one of the Polycyclic Aromatic Hydrocarbons (PAHs that are formed during the incomplete combustion of fossil fuels, oil pollution and different process of oil and gas plants. PAHs-contaminated area have increased a health risk to humans and environments due to toxicity, carcinogenicity, hydrophobicity and their tendency to accumulation in soil and sediment and their entrance to food chain. Bioremediation is an effective method for removing toxic pollutants from soils such as Phenanthrene. The main object of this study is the assessment of the effects of salinity on the efficacy of the process of bioremediation on polluted soils by Phenanthrene. Methods: The bare soil of any organic and microbial pollution was first polluted artificially to the phenanthrene then a nutrient solution with two minimum and maximum concentrations of salinity were added to it in order to have the proportion of 10% w:v (soil: water. After that a microbial mixture which was enable degradation the phenanthrene added to the slurry and aerated. After the extraction of phenanthrene by ultrasonic, the residual concentration in the soil was analyzed by GC. Results: In the conditions that salinity concentration was maximum, the microbial growth has a longer lag phase than the minimum salinity. The findings from extraction process by GC depict the removal percentage of maximum and minimum salinity in 56th %70.5 day and %71.8, respectively. Conclusion: In In spite of the longer log phase of maximum concentration of salinity and according to GC results, there was just a little difference between two solutions. Therefore it reveals that salinity can increase the lag phase but haven't any inhibitory effect on Phenanthrene removal.

  14. [Soil Salinity Estimation Based on Near-Ground Multispectral Imagery in Typical Area of the Yellow River Delta].

    Science.gov (United States)

    Zhang, Tong-rui; Zhao, Geng-xing; Gao, Ming-xiu; Wang, Zhuo-ran; Jia, Ji-chao; Li, Ping; An, De-yu

    2016-01-01

    This study chooses the core demonstration area of 'Bohai Barn' project as the study area, which is located in Wudi, Shandong Province. We first collected near-ground and multispectral images and surface soil salinity data using ADC portable multispectral camera and EC110 portable salinometer. Then three vegetation indices, namely NDVI, SAVI and GNDVI, were used to build 18 models respectively with the actual measured soil salinity. These models include linear function, exponential function, logarithmic function, exponentiation function, quadratic function and cubic function, from which the best estimation model for soil salinity estimation was selected and used for inverting and analyzing soil salinity status of the study area. Results indicated that all models mentioned above could effectively estimate soil salinity and models using SAVI as the dependent variable were more effective than the others. Among SAVI models, the linear model (Y = -0.524x + 0.663, n = 70) is the best, under which the test value of F is the highest as 141.347 at significance test level, estimated R2 0.797 with a 93.36% accuracy. Soil salinity of the study area is mainly around 2.5 per thousand - 3.5 per thousand, which gradually increases from southwest to northeast. The study has probed into soil salinity estimation methods based on near-ground and multispectral data, and will provide a quick and effective technical soil salinity estimation approach for coastal saline soil of the study area and the whole Yellow River Delta.

  15. Trend Analysis of Soil Salinity in Different Land Cover Types Using Landsat Time Series Data (case Study Bakhtegan Salt Lake)

    Science.gov (United States)

    Taghadosi, M. M.; Hasanlou, M.

    2017-09-01

    Soil salinity is one of the main causes of desertification and land degradation which has negative impacts on soil fertility and crop productivity. Monitoring salt affected areas and assessing land cover changes, which caused by salinization, can be an effective approach to rehabilitate saline soils and prevent further salinization of agricultural fields. Using potential of satellite imagery taken over time along with remote sensing techniques, makes it possible to determine salinity changes at regional scales. This study deals with monitoring salinity changes and trend of the expansion in different land cover types of Bakhtegan Salt Lake district during the last two decades using multi-temporal Landsat images. For this purpose, per-pixel trend analysis of soil salinity during years 2000 to 2016 was performed and slope index maps of the best salinity indicators were generated for each pixel in the scene. The results of this study revealed that vegetation indices (GDVI and EVI) and also salinity indices (SI-1 and SI-3) have great potential to assess soil salinity trends in vegetation and bare soil lands respectively due to more sensitivity to salt features over years of study. In addition, images of May had the best performance to highlight changes in pixels among different months of the year. A comparative analysis of different slope index maps shows that more than 76% of vegetated areas have experienced negative trends during 17 years, of which about 34% are moderately and highly saline. This percent is increased to 92% for bare soil lands and 29% of salt affected soils had severe salinization. It can be concluded that the areas, which are close to the lake, are more affected by salinity and salts from the lake were brought into the soil which will lead to loss of soil productivity ultimately.

  16. Development and application of a conceptual hydrologic model to predict soil salinity within modern Tunisian oases

    Science.gov (United States)

    Askri, Brahim; Bouhlila, Rachida; Job, Jean Olivier

    2010-01-01

    SummaryIn modern oases situated in the south of Tunisia, secondary salination of irrigated lands is a crucial problem. The visible salt deposits and soil salination processes are the consequence of several factors including the excessive use of saline irrigation water, seepage from earthen canal systems, inefficient irrigation practices and inadequate drainage. Understanding the mechanism of the secondary salination is of interest in order to maintain existing oases, and thus ensure the sustainability of date production in this part of the country. Therefore, a conceptual, daily, semi-distributed hydrologic model (OASIS_MOD) was developed to analyse the impact of irrigation management on the water table fluctuation, soil salinity and drain discharge, and to evaluate measures to control salinity within an oasis ecosystem. The basic processes incorporated in the model are irrigation, infiltration, percolation to the shallow groundwater, soil evaporation, crop transpiration, groundwater flow, capillary rise flux, and drain discharge. OASIS_MOD was tested with data collected in a parcel of farmland situated in the Segdoud oasis, in the south-west of Tunisia. The calibration results showed that groundwater levels were simulated with acceptable accuracy, since the differences between the simulated and measured values are less than 0.22 m. However, the model under-predicted some water table peaks when irrigation occurs due to inconsistencies in the irrigation water data. The validation results showed that deviations between observed and simulated groundwater levels have increased to about 0.5 m due to under-estimation of groundwater inflow from an upstream palm plantation. A long-term simulation scenario revealed that the soil salinity and groundwater level have three types of variability in time: a daily variability due to irrigation practices, seasonal fluctuation due to climatic conditions and annual variability explained by the increase in cultivated areas. The

  17. Evolutionary history influences the salinity preference of bacterial taxa in wetland soils

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    Ember M Morrissey

    2015-10-01

    Full Text Available Salinity is a major driver of bacterial community composition across the globe. Despite growing recognition that different bacterial species are present or active at different salinities, the mechanisms by which salinity structures community composition remain unclear. We tested the hypothesis that these patterns reflect ecological coherence in the salinity preferences of phylogenetic groups using a reciprocal transplant experiment of fresh- and saltwater wetlands soils. The salinity of both the origin and host environments affected community composition (16S rRNA gene sequences and activity (e.g., extracellular enzyme activity, CO2, and CH4 production. These changes in community composition and activity rates were strongly correlated, which suggests the effect of environment on function could be mediated, at least in part, by microbial community composition. Based on their distribution across treatments, each phylotype was categorized as having a salinity preference (freshwater, saltwater, or none and phylogenetic analyses revealed a significant influence of evolutionary history on these groupings. This finding was corroborated by examining the salinity preferences of high-level taxonomic groups. For instance, we found that the majority of alpha- and gamma-proteobacteria preferred saltwater, while many beta-proteobacteria prefer freshwater. Overall, our results indicate the effect of salinity on bacterial community composition results from phylogenetically-clustered salinity preferences.

  18. Sustainable Management of Calcareous Saline-Sodic Soil in Arid Environments: The Leaching Process in the Jordan Valley

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    Mufeed Batarseh

    2017-01-01

    Full Text Available A leaching experiment of calcareous saline-sodic soil was conducted in Jordan Valley and aimed to reduce the soil salinity ≤ 4.0 dS m−1. The quantification of salt removal from the effective root zone was done using three treatment scenarios. Treatment A contained soil amended with gypsum leaching with fresh water (EC = 1.1 dS m−1. Treatments B and C contained nonamended soil, but B was leached with fresh water only while treatment C’s soil was washed with saline agricultural drainage water (EC = 8 dS m−1 at the start of the experiment and continued with fresh water to reach the desired soil salinity. All treatments were able to reduce the soil salinity to the desired level at the end of the experiment; however, there were clear differences in the salt removal efficiencies among the treatments which were attributed to the presence of direct source of calcium ion. The soil amended with gypsum caused a substantial decline in soil salinity and drainage water’s electrical conductivity and drained the water twice as fast as the nonamended soil. It was found that utilizing agricultural drainage water and gypsum as a soil amendment for calcareous saline-sodic soil reclamation can beneficially contribute to sustainable agricultural management in the Jordan Valley.

  19. Detecting crop yield reduction due to irrigation-induced soil salinization in South-West Russia

    Science.gov (United States)

    Argaman, E.; Beets, W.; Croes, J.; Keesstra, S.; Verzandvoort, S.; Zeiliguer, A.

    2012-04-01

    The South-European part of the Russian Federation has experienced serious land degradation in the form of soil salinization since the 1960s. This land degradation was caused by intensive, large-scale irrigation on reclaimed land in combination with the salt-rich nature of the substrate. Alkaline soil salinity is believed to be an important factor decreasing crop yield in this area. A large research effort has been directed to the effects of soil salinity on crops, there is a need for simple, easily determinable indicators of crop health and soil salinity in irrigated systems, that can help to detect crop water stress in an early stage. The objectives of this research were to study the effects of soil salinity and vegetation water stress on the performance of alfalfa crop yield and physiological crop properties, and to study the possibility to measure soil salinity and alkalinity and the crop water stress index at plot level using a thermal gun and a regular digital camera. The study area was located in Saratov District, in the South-West part of Russia. Variables on the surface energy balance, crop properties, soil properties and visible reflectance were measured on plots with alfalfa cultures in two fields with and without signs of alkaline soil salinity, and with and without irrigation in July 2009. The research showed no clear adverse effects of soil salinity and soil alkalinity on crop yield and physiological crop properties. Soil salinity, as reflected by the electric conductivity, positively affected the root biomass of alfalfa in the range of 0.15 to 1.52 dS/m . This was a result of EC levels being below the documented threshold to negatively affect Alfalfa, as would be the case in truly saline soils. The soil pH also showed a positive correlation with root biomass within the range of pH 6.2 and 8.5 . From the literature these pH values are generally believed to be too high to exhibit a positive relationship with root biomass. No relationship was found

  20. Assessments of saline water application and different irrigation intervals on soil and soybean yield

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    Meysam Abedinpour

    2016-06-01

    Full Text Available The global water crisis reminds the important of enhancing water productivity in agriculture to increase the crop production and food security. Declining availability of fresh water resources has become a worldwide problem which promotes the new alternative sources of water-supply to overcome to this issue. In this goal, the effects of different irrigation intervals and water quality on soybean growth and soil properties were investigated by a field split plot experiment in a randomized completely block design water in three replications. Different saline water levels (1, 4 and 7 dS m-1 and three irrigation intervals (7, 10 and 13 days were arranged as studied factors in main and subplot, respectively. The maximum performance was obtained by the treatment of 7 days irrigation interval+non-saline water which produced 3760 and 8355 kg ha-1 grain yield and biomass, respectively. Also, maximum water use efficiency of 9.08 kg ha-1mm-1 was obtained by 13 days irrigation interval+7 dS m-1 salinity. Maximum soil salinity (ECe in different soil layers was observed in the highest irrigation saline water treatment (7 dS m-1 in all irrigation intervals. Moreover, irrigation with highest salinity level (S3 resulted in the salt accumulation in the root zone from 1.4 dS m-1 (before sowing up to 5.7 dS m-1 at the end of growing period. Therefore, based on soil salinity and crop yield, irrigation interval 7 days at lower levels of irrigation water salinities (up to 4 dS m-1 is suitable for soybean production in the semi-arid environment.

  1. Causal mechanisms of soil organic matter decomposition: Deconstructing salinity and flooding impacts in coastal wetlands

    Science.gov (United States)

    Stagg, Camille L.; Schoolmaster, Donald; Krauss, Ken W.; Cormier, Nicole; Conner, William H.

    2017-01-01

    Coastal wetlands significantly contribute to global carbon storage potential. Sea-level rise and other climate change-induced disturbances threaten coastal wetland sustainability and carbon storage capacity. It is critical that we understand the mechanisms controlling wetland carbon loss so that we can predict and manage these resources in anticipation of climate change. However, our current understanding of the mechanisms that control soil organic matter decomposition, in particular the impacts of elevated salinity, are limited, and literature reports are contradictory. In an attempt to improve our understanding of these complex processes, we measured root and rhizome decomposition and developed a causal model to identify and quantify the mechanisms that influence soil organic matter decomposition in coastal wetlands that are impacted by sea-level rise. We identified three causal pathways: 1) a direct pathway representing the effects of flooding on soil moisture, 2) a direct pathway representing the effects of salinity on decomposer microbial communities and soil biogeochemistry, and 3) an indirect pathway representing the effects of salinity on litter quality through changes in plant community composition over time. We used this model to test the effects of alternate scenarios on the response of tidal freshwater forested wetlands and oligohaline marshes to short- and long-term climate-induced disturbances of flooding and salinity. In tidal freshwater forested wetlands, the model predicted less decomposition in response to drought, hurricane salinity pulsing, and long-term sea-level rise. In contrast, in the oligohaline marsh, the model predicted no change in response to sea-level rise, and increased decomposition following a drought or a hurricane salinity pulse. Our results show that it is critical to consider the temporal scale of disturbance and the magnitude of exposure when assessing the effects of salinity intrusion on carbon mineralization in coastal

  2. Effect of saline soil parameters on endo mycorrhizal colonisation of dominant halophytes in four Hungarian sites

    Energy Technology Data Exchange (ETDEWEB)

    Fuzy, A.; Biro, B.; Toth, T.

    2010-07-01

    Soil and root samples were collected from the rhizosphere of dominant halophytes (Artemisia santonicum, Aster tripolium, Festuca pseudovina, Lepidium crassifolium, Plantago maritima and Puccinellia limosa) at four locations with saline soils in Hungary. The correlations- between arbuscular mycorrhiza (AM) fungal colonisation parameters (% colonisation, % arbuscules) and soil physical, chemical and biological parameters were determined Endomycorrhiza colonisation was found to be negatively correlated with the electric conductivity of the soil paste, the salt-specific ion concentrations and the cation exchange capacity, showing the sensitivity of AM fungi at increasing salt concentrations, independently of the types of salt-specific anions. A positive correlation was detected between the mycorrhiza colonisation and the abundance of oligotroph bacteria known to be the less variable and more stable (k-strategist) group. This fact and the negative correlation found with the humus content underlines the importance of nutrient availability and the limitations of the symbiotic interactions in stressed saline or sodic soils. (Author) 29 refs.

  3. THE HALOPHILICITY OF FILAMENTOUS FUNGI ISOLATED FROM SALINE SOILS OF SOUTH CAUCASUS

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    Kvesitadze E.

    2015-08-01

    Full Text Available The work is devoted to the isolation, purification, determination of taxonomical characteristics and application in soil improvement and other biotechnological processes halophilic microscopic fungi strains isolated from saline soils of Eastern Georgia (middle part of South Caucasus, where their existence is maximally supposed. In all soilclimatic zones the dominate forms of spread fungi are genera Aspergillus, Penicillium and Fusarium, followed by Trichoderma and Mucor. Other genera are met less intensively. The genera Aspergillus is widely spread in chestnut soils and in chernozem, in green forest soils the genera Penicillium is prevailing. The salinity of soil, lake or any other objects from which the isolation of microscopic fungi is performed greatly determines halophilisity of isolated strains. Finally, the collection of halophilic microscopic fungi has been created accounting 96 isolates of extreme halophiles, halophiles and week halophiles.

  4. GROWTH AND REGROWTH OF NEEM AFTER CUTTING IN SALINE - SODIC SOIL TREATED WITH ORGANIC INPUTS

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    RUMMENIGGE DE MACÊDO RODRIGUES

    2017-01-01

    Full Text Available Soil salinity and sodicity are global problems since both promote the physical, chemical and biological degradation of soil, jeopardising the productive capacity of agricultural fields. Inorganic correctives or organic inputs are applied as an attempt to reduce the problem, alongside the use of salt-tolerant plants. This study aimed at evaluating the effects of organic inputs on the growth of neem (Azadirachta indica strains in saline-sodic soil after cutting. Treatments were arranged in a randomised block design, with four replicates in a 3 × 5 factorial. Organic inputs — bovine manure, common bovine biofertilizer (equal parts of water and fresh bovine manure and chemically enriched biofertilizer (common biofertilizer components combined with plaster, sugarcane molasses and cow’s milk — were applied only once, after soil washing, two days prior to seeding, at the levels of 0, 3, 6, 9 and 12% of the substrate volume. Except effects on the stem diameter, the most efficient input was bovine manure, with strong effects on the height increase and biomass yield of neem plants after cutting, especially in treatments at a level greater than 6%. The organic inputs, despite increasing the soil salinity and sodicity in the interval between washing and cutting, stimulated biometric growth and biomass formation in saline-sodic soil.

  5. A Study on the Coupled Model of Hydrothermal-Salt for Saturated Freezing Salinized Soil

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    Xudong Zhang

    2017-01-01

    Full Text Available Water and heat interact in the process of freezing for the saturated soil. And for the salinized soil, water, heat, and salt interact in the freezing process, because salinized soil has soluble salt. In this paper, a one-dimensional mathematical coupled model of hydraulic-thermal-salt is established. In the model, Darcy’s law, law of conservation of energy, and law of conservation of mass are applied to derive the equations. Consider that a saturated salinized soil column is subjected to the condition of freezing to model the moisture migration and salt transport. Both experiment and numerical simulation under the same condition are developed in the soil column. Then the moisture content and salt content between simulation and experiment are compared. The result indicates that simulation matches well with the experiment data, and after 96 hours, the temperature distribution becomes stable, freezing front reaches a stable position, and a lot of unfrozen water has time to migrate. Besides, the excess salt precipitates when the concentration is greater than the solubility, and the precipitation is distributed discontinuously. These results can provide reference for engineering geology and environmental engineering in cold region and saline soil area.

  6. Development of predictive mapping techniques for soil survey and salinity mapping

    Science.gov (United States)

    Elnaggar, Abdelhamid A.

    Conventional soil maps represent a valuable source of information about soil characteristics, however they are subjective, very expensive, and time-consuming to prepare. Also, they do not include explicit information about the conceptual mental model used in developing them nor information about their accuracy, in addition to the error associated with them. Decision tree analysis (DTA) was successfully used in retrieving the expert knowledge embedded in old soil survey data. This knowledge was efficiently used in developing predictive soil maps for the study areas in Benton and Malheur Counties, Oregon and accessing their consistency. A retrieved soil-landscape model from a reference area in Harney County was extrapolated to develop a preliminary soil map for the neighboring unmapped part of Malheur County. The developed map had a low prediction accuracy and only a few soil map units (SMUs) were predicted with significant accuracy, mostly those shallow SMUs that have either a lithic contact with the bedrock or developed on a duripan. On the other hand, the developed soil map based on field data was predicted with very high accuracy (overall was about 97%). Salt-affected areas of the Malheur County study area are indicated by their high spectral reflectance and they are easily discriminated from the remote sensing data. However, remote sensing data fails to distinguish between the different classes of soil salinity. Using the DTA method, five classes of soil salinity were successfully predicted with an overall accuracy of about 99%. Moreover, the calculated area of salt-affected soil was overestimated when mapped using remote sensing data compared to that predicted by using DTA. Hence, DTA could be a very helpful approach in developing soil survey and soil salinity maps in more objective, effective, less-expensive and quicker ways based on field data.

  7. [Spatial variation of soil moisture/salinity and the relationship with vegetation under natural conditions in Yancheng coastal wetland].

    Science.gov (United States)

    Zhang, Hua-Bing; Liu, Hong-Yu; Li, Yu-Feng; An, Jing; Xue, Xing-Yu; Hou, Ming-Hang

    2013-02-01

    Taking the core part of Yancheng national nature reserve as the study area, according to soil sampling analysis of coastal wetlands in April and May 2011 land the 2011 ETM + remote sensing image, the spatial difference characteristic of coastal wetlands soil moisture and salinity, and the relationship with vegetation under natural conditions, were investigated with the model of correspondence analysis (CCA), linear regression simulation and geo-statistical method. The results showed: Firstly, the average level of the soil moisture was fluctuating between 36.820% and 46.333% , and the soil salinity was between 0.347% and 1.328% , in a more detailed sense, the Spartina swamp was the highest, followed by the mudflats swamp, the Suaeda salsa swamp, and the Reed marsh. Secondly, the spatial variation of soil moisture was consistent with that of the salinity, and the degree of variation in the east-west direction was greater than that in the north-south. The maximum soil moisture and salinity were found in the southwest Spartina swamp. The minimum was in the Reed swamp. The soil moisture and salinity were divided into 5 levels, from I to V. Level IV occupied the highest proportion, which were 36.156% and 28.531% , respectively. Finally, different landscape types with the combination of soil moisture and salinity showed a common feature that the moisture and salinity were from both high to low. The soil moisture value of Reed marshes was lower than 40.116% and the salinity value was lower than 0. 676% . The soil moisture value of Suaeda salsa marshes was between 38. 162% and 46. 403% and the salinity value was between 0.417% and 1.295%. The soil moisture value of Spartina swamp was higher than 43.214% and the salinity was higher than 1.090%. The soil moisture value of beach was higher than 43.214% and the salinity was higher than 0.677%.

  8. Use of mixed solid waste as a soil amendment for saline-sodic soil remediation and oat seedling growth improvement.

    Science.gov (United States)

    Fan, Yuan; Ge, Tian; Zheng, Yanli; Li, Hua; Cheng, Fangqin

    2016-11-01

    Soil salinization has become a worldwide problem that imposes restrictions on crop production and food quality. This study utilizes a soil column experiment to address the potential of using mixed solid waste (vinegar residue, fly ash, and sewage sludge) as soil amendment to ameliorate saline-sodic soil and enhance crop growth. Mixed solid waste with vinegar residue content ranging from 60-90 %, sewage sludge of 8.7-30 %, and fly ash of 1.3-10 % was added to saline-sodic soil (electrical conductivity (EC1:5) = 1.83 dS m-1, sodium adsorption ratio (SAR1:5) = 129.3 (mmolc L-1)1/2, pH = 9.73) at rates of 0 (control), 130, 260, and 650 kg ha-1. Results showed that the application of waste amendment significantly reduced SAR, while increasing soil soluble K+, Ca2+, and Mg2+, at a dose of 650 kg ha-1. The wet stability of macro-aggregates (>1 mm) was improved 90.7-133.7 % when the application rate of amendment was greater than 260 kg ha-1. The application of this amendment significantly reduced soil pH. Germination rates and plant heights of oats were improved with the increasing rate of application. There was a positive correlation between the percentage of vinegar residue and the K/Na ratio in the soil solutions and roots. These findings suggest that applying a mixed waste amendment (vinegar residue, fly ash, and sewage sludge) could be a cost-effective method for the reclamation of saline-sodic soil and the improvement of the growth of salt-tolerant plants.

  9. The Effect of Water Table Fluctuation and its Salinity on Fe Crystal and Noncrystal in some Khuzestan Soils

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    mostafa Pajohannia

    2017-01-01

    Full Text Available Introduction: Iron is found in different forms in the soil. In the primary minerals, iron is found as Fe3+ or Fe2+ which converted to Fe2+ and released in unsuitable reduction conditions. Minerals such as sulfide or chlorine and bicarbonate can affect and change the different forms soil Fe. FeAs these elements are abundance in groundwater or soil, they are capable to react chemically with Fe and change different Fe forms and also may deposit or even leach them by increasing its solubility in the soil. Water table fluctuation is a regular phenomenon in Khuzestan that Fe forms change under these situations. The study of Fe oxide forms and its changes can be applied for evaluation of soil development. Therefore, the aim of this study is the water table fluctuation and its quality effects, and some physio-chemical properties on Fe oxides forms in non-saline and saline soils in Khuzestan. Materials and Methods: Soil samples were collected from two regions: saline (Abdolkhan and non-saline (South Susa regions. soil samples were collected from all horizons of 12 soil field studied profiles . The samples were analyzed for soil texture, pH, EC (soil: water ratio 1:5, organic carbon and aggregate stability (Kemper and Rosenau method. Fe forms also were extracted by two methods in all samples: di-tyonite sodium and ammonium oxalate extraction. Fe oxalate extracted was related to Feo (non crystal Fe and Fed-Feo was related to Fec (crystalline Fe. The Fe content were determined by atomic absorbtion spectrophotometer (AAS. Data were analysis in SAS and Excel software and results were presented. Results and Discussion: The results showed that texture were loamy sand to silty clay loam, OM was very poor (0.1-0.7%. The soil salinity was also 2.8-16.8 dS/m. Calcium carbonate equivalent was 38-40%. All pedons were classified in Entisols and Inceptisols according to Keys to soil taxonomy (2010. The results showed that the proportion of Fe with oxalate to di

  10. The U.S. Salinity Laboratory (USDA-ARS) guidelines for assessing multi-scale soil salinity with proximal and remote sensing

    Science.gov (United States)

    Scudiero, Elia; Skaggs, Todd; Corwin, Dennis

    2017-04-01

    Soil salinity is a major threat to sustainable agriculture, especially in arid and semi-arid regions. Updated and accurate inventories of salinity in agronomically and environmentally relevant ranges (i.e., essential for producers and decision-makers to assure long term food production. Over the past three decades, scientists at the U.S. Salinity Laboratory (USDA-ARS) in Riverside, CA have developed proximal sensor (i.e., electrical resistivity and electromagnetic induction) and remote imagery (e.g., MODIS, Landsat, WorldView) methodologies for assessing soil salinity at multiple scales: field (0.5 ha to 1 km2), landscape (1 to 10 km2), and regional (10 to 105 km2) scales. The purpose of this contribution is to provide an overview of these scale-dependent salinity assessment approaches. Guidelines, special considerations, and strengths and limitations of each scale-specific approach are presented for characterizing spatial and temporal variation in soil salinity. To support the discussion, we present a regional scale dataset comprising salinity surveys over 22 fields in California, USA. The dataset is used to provide practical examples of field-, landscape-, and regional-scale soil salinity assessment.

  11. Simple sensors to achieve fine spatial resolution in continuous measurements of soil moisture and salinity

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    F. Konukcu

    2002-01-01

    Full Text Available It is increasingly necessary to be able to measure, simultaneously, continuously and at fine spatial resolution, the salinity and water content of soil. This paper reports the design, construction, calibration and laboratory testing of two simple but robust instruments that enable this to be achieved. Salinity in solution was measured reliably, at 10-mm spacing, by multi-electrode resistivity probes up to saturation with NaCl (c. 6 mol l–1, though these probes required individual calibration and were unable to detect precipitated salt. Volumetric water content was measured with great sensitivity over a wide range, from air-dryness (0.06 m3m–3 to saturation (0.55 m3m–3 in a sandy loam, using thermal-conductivity probes that used a common calibration and were unaffected by the salinity of the soil solution, by temperature and by ageing. Keywords: soil moisture, soil salinity, thermal-conductivity moisture probe, four-electrode salinity probe

  12. Growth and nutrient concentrations of maize in pressmud treated saline-sodic soils

    Directory of Open Access Journals (Sweden)

    D. Muhammad

    2009-05-01

    Full Text Available n open-air pot experiment was conducted to investigate effects of pressmud (PM on saline-sodic soil reclamation, mitigating the adverse effects of saline irrigation and increase of maize (Zea mays L. growth. Pressmud was added at the rate of 0, 5, 10 and 20 Mg ha-1 to pots containing 6.8 kg air dried surface (0-20 cm soil collected from two sites. The increasing levels of PM enhanced maize plant height, shoots and roots biomass in both soils. However, the Soil 2, with initial EC and SAR of 5.43 dS m-1 and 18.67(m mol L-11/2, respectively, produced comparatively more biomass at all PM levels than Soil 1 [silty-clay loam, EC = 6.22 dS m-1, SAR = 20.72 (m mol L- 1 1/2]. The [P] in shoots was maximum at the highest PM in both the soils but the [K] increased with PM levels in Soil 1 and decreased in Soil 2 due to the dilution effect. The Soil 1 maintained several folds more [Na] in shoots and consequently lower K:Na ratio than Soil 2. The post harvest soil pH, Na, Ca+Mg and SAR in saturation extracts decreased with increasing levels of PM as compared to control. Soil 2 released more volume of leachate as compared to Soil 1 but the leachate EC and [Na] were comparable while [Ca+Mg] were relatively higher in Soil 2. The higher removal of total salts from Soil 2 resulted in lower soil pH, EC and SAR in this soil as compared to Soil 1. The increases in crop growth with each increment of PM up to 20 Mg ha-1 in the present study proved the benefits of PM in increasing crop yields and suggested that doses higher than 20 Mg PM ha-1 could be applied to the saline-sodic soils ofthe area to get maximum possible crop yields depending on soil and water quality

  13. Irrigation with saline-sodic water: effects on two clay soils

    Directory of Open Access Journals (Sweden)

    Giovanna Cucci

    2013-05-01

    Full Text Available The results of a 4-year experiment aimed at evaluating the effect of irrigation with saline-sodic water on the soil are reported. The research was carried out at the Campus of the Agricultural Faculty of Bari University (Italy on 2 clay soils (Bologna – T1 and Locorotondo – T2. The soils were cropped to borlotto bean (Phaseolus vulgaris L., capsicum (Capsicum annuum L., sunflower (Helianthus annuus L., wheat (Triticum durum Desf grown in succession; the crops were irrigated with 9 saline-sodic types of water and subjected to two different leaching fractions (10% and 20% of the watering volume. The 9 solutions were obtained dissolving in de-ionised water weighted amounts of sodium chloride (NaCl and calcium chloride (CaCl2, deriving from the combination of 3 saline concentrations and 3 sodicity levels. The crops were irrigated whenever the water lost by evapotranspiration from the soil contained in the pots was equal to 30% of the soil maximum available water. The results showed that, though the soils were leached during the watering period, they showed a high salt accumulation. Consequently, the saturated soil extract electrical conductivity increased from initial values of 0.65 and 0.68 dS m-1 to 11.24 and 13.61 dS m-1 at the end of the experiment, for the soils T1 and T2, respectively. The saline concentration increase in irrigation water caused in both soils a progressive increase in exchangeable sodium, and a decrease in exchangeable calcium and non-significant variations in exchangeable potassium (K and magnesium (Mg.

  14. The arbuscular mycorrhizal fungus Glomus geosporum in European saline, sodic and gypsum soils.

    Science.gov (United States)

    Landwehr, Melanie; Hildebrandt, Ulrich; Wilde, Petra; Nawrath, Kerstin; Tóth, Tibor; Biró, Borbála; Bothe, Hermann

    2002-08-01

    Plants of saline and sodic soils of the Hungarian steppe and of gypsum rock in the German Harz mountains, thus soils of high ionic strength and electric conductivity, were examined for their colonization by arbuscular mycorrhizal fungi (AMF). Roots of several plants of the saline and sodic soils such as Artemisia maritima, Aster tripolium or Plantago maritima are strongly colonized and show typical AMF structures (arbuscules, vesicles) whereas others like the members of the Chenopodiaceae, Salicornia europaea, Suaeda maritima or Camphorosma annua, are not. The vegetation of the gypsum rock is totally different, but several plants are also strongly colonized there. The number of spores in samples from the saline and sodic soils examined is rather variable, but high on average, although with an apparent low species diversity. Spore numbers in the soil adjacent to the roots of plants often, but not always, correlate with the degree of AMF colonization of the plants. As in German salt marshes [Hildebrandt et al. (2001)], the dominant AMF in the Hungarian saline and sodic soils is Glomus geosporum. All these isolates provided nearly identical restriction fragment length polymorphism (RFLP) patterns of the internal transcribed spacer (ITS) region of spore DNA amplified by polymerase chain reaction (PCR). Cloning and sequencing of several PCR products of the ITS regions indicated that ecotypes of the G. geosporum/ Glomus caledonium clade might exist at the different habitats. A phylogenetic dendrogram constructed from the ITS or 5.8S rDNA sequences was nearly identical to the one published for 18S rDNA data (Schwarzott et al. 2001). It is tempting to speculate that specific ecotypes may be particularly adapted to the peculiar saline or sodic conditions in such soils. They could have an enormous potential in conferring salt resistance to plants.

  15. Seasonal flooding, soil salinity and primary production in northern prairie marshes.

    Science.gov (United States)

    Neill, Christopher

    1993-10-01

    Hydrologic regime is an important control of primary production in wetland ecosystems. I investigated the coupling of flooding, soil salinity and plant production in northern prairie marshes that experience shallow spring flooding. Field experiments compared whitetop (Scolochloa festucacea) marsh that was: (1) nonflooded, (2) flooded during spring with 25 cm water and (3) nonflooded but irrigated with 1 cm water · day-1. Pot culture experiments examined whitetop growth response to salinity treatments. The electrical conductivity of soil interstitial water (ECe) at 15 cm depth was 4 to 8 dS· m-1 lower in flooded marsh compared with nonflooded marsh during 2 years. Whitetop aboveground biomass in flooded marsh (937 g · m-2, year 1; 969 g · m-2, year 2) exceeded that of nonflooded marsh (117 g · m-2 year 1; 475 g · m-2, year 2). Irrigated plots had lower ECe and higher aboveground biomass than nonflooded marsh. In pot culture, ECe of 4.3 dS · m-1 (3 g · L-1 NaCl) reduced total whitetop biomass by 29 to 44% and ECe of 21.6 dS · m-1 (15 g · L-1 NaCl) reduced biomass by more than 75%. Large reductions of ECe and increases of whitetop growth with irrigation indicated that plants responded to changes in soil salinity and not other potential environmental changes caused by inundation. The results suggest that spring flooding controls whitetop production by decreasing soil salinity during spring and by buffering surface soils against large increases of soil salinity after mid-summer water level declines. This mechanism can explain higher marsh plant production under more reducing flooded soil conditions and may be an important link between intermittent flooding and primary production in other wetland ecosystems.

  16. Ectomycorrhizal fungal community in alkaline-saline soil in northeastern China.

    Science.gov (United States)

    Ishida, Takahide A; Nara, Kazuhide; Ma, Shurong; Takano, Tetsuo; Liu, Shenkui

    2009-06-01

    Alkaline-saline soil is widespread in arid and semiarid regions of the world and causes severe environmental and agricultural problems. To advance our understanding of the adaptation of ectomycorrhizal fungi (EMF) to alkaline-saline soil, we investigated EMF communities on Mongolian willow (Salix linearistipularis) growing in alkaline-saline soil (up to pH 9.2) in northeastern China. In total, 75 root samples were collected from 25 willow individuals over 4.7 ha. To identify fungal species in ectomycorrhizal root tips, we used terminal restriction fragment length polymorphism and sequencing analyses of the internal transcribed spacer region of ribosomal DNA. We detected 11 EMF species, including species of Inocybe, Hebeloma, and Tomentella of the Basidiomycota and three Ascomycota species. The EMF richness of the study site was estimated to be 15-17 using major estimators. The most abundant species was Geopora sp. 1, while no Geopora-dominated EMF communities have been reported so far. Phylogenetic analysis showed that the phylogroup including Geopora sp. 1 has been found mostly in alkaline soil habitats, indicating its adaptation to high soil pH. Because EMF are indispensable for host plant growth, the EMF species detected in this study may be useful for restoration of alkaline-saline areas.

  17. Identification of saline soils with multi-year remote sensing of crop yields

    Energy Technology Data Exchange (ETDEWEB)

    Lobell, D; Ortiz-Monasterio, I; Gurrola, F C; Valenzuela, L

    2006-10-17

    Soil salinity is an important constraint to agricultural sustainability, but accurate information on its variation across agricultural regions or its impact on regional crop productivity remains sparse. We evaluated the relationships between remotely sensed wheat yields and salinity in an irrigation district in the Colorado River Delta Region. The goals of this study were to (1) document the relative importance of salinity as a constraint to regional wheat production and (2) develop techniques to accurately identify saline fields. Estimates of wheat yield from six years of Landsat data agreed well with ground-based records on individual fields (R{sup 2} = 0.65). Salinity measurements on 122 randomly selected fields revealed that average 0-60 cm salinity levels > 4 dS m{sup -1} reduced wheat yields, but the relative scarcity of such fields resulted in less than 1% regional yield loss attributable to salinity. Moreover, low yield was not a reliable indicator of high salinity, because many other factors contributed to yield variability in individual years. However, temporal analysis of yield images showed a significant fraction of fields exhibited consistently low yields over the six year period. A subsequent survey of 60 additional fields, half of which were consistently low yielding, revealed that this targeted subset had significantly higher salinity at 30-60 cm depth than the control group (p = 0.02). These results suggest that high subsurface salinity is associated with consistently low yields in this region, and that multi-year yield maps derived from remote sensing therefore provide an opportunity to map salinity across agricultural regions.

  18. The Comparison of Micromorphological properties of Saline – Sodic and Nonsaline-Nonsodic Soils around the Urmia Lake

    Directory of Open Access Journals (Sweden)

    S. chakherloo

    2015-06-01

    Full Text Available In order to comparision of the micromorphic properties of saline-sodic and nonsaline-nonsodic soils in the west of Urmia Lake, four soil profiles (2profile in saline-sodic soils and 2profiles in nonsaline-nonsodic soils were investigated. These profiles were described and sampled using standard methods. soil samples were used for physico chemical analysis and undisturbed and oriented samples were used for thin section preparation. Thin sections were studied using polarizing microscope in PPL and XPL lights. Thin sections studies showed that saline-sodic soils are structure less (apedal, and their voids are mostly vughs and channel and as a result, their, nonsaline-nonsodic soils are pedal with compound packing voids, vughs and planar voids and as a result, The b.fabric in these to group of soils is crystallitic. In saline sodic soils pedofeatures are illuvial clay coatings, salt accumulations including coatings and infillings of halite in channel and vughs. These pedofeatures were not seen in nonsaline-nonsodic soils. Organic coatings were seen as black colored films on peds and in some cases mixed with groundmass of saline-sodic soils.Calcium carbonate accumulations as nodules and coatings and nodules and coatings of iron and Mn oxides were seen in both saline-sodic and nonsaline-nonsodic soils.

  19. Biogenic nitric oxide emission from saline sodic soils in a semiarid region, northeastern China: A laboratory study

    Science.gov (United States)

    Yu, Junbao; Meixner, Franz X.; Sun, Weidong; Liang, Zhengwei; Chen, Yuan; Mamtimin, Buhalqem; Wang, Guoping; Sun, Zhigao

    2008-12-01

    It is well-known that nitric oxide (NO) is an important component in nitrogen biogeochemical cycling produced through biological process of nitrification and denitrification in soils, but the production and the consumption processes of NO in sodic saline soil are less understood. Through a series of laboratory experiments focusing on NO biogenic emissions from four kinds of saline sodic soils of different land use in western Songnen Plain northestern China, we found that the optimum soil moisture for the maximum NO production and emission were 14.0%, 9.0%, 9.5%, and 18% water-filled pore space (WFPS) for soil samples from natural pasture, man-made pasture, paddy field of saline sodic soil mixed sandy soil, and paddy field of pure saline sodic soil, respectively. For a given moisture, NO fluxes increased exponentially with soil temperature at any given soil moisture. The optimum soil moisture for the maximum NO emission for a certain soil type, however, was constant and independent of soil temperature. The NO consumption processes for different land uses were similar in all studied saline sodic soils since the difference of NO consumption rate constant in these soils was small (ranged from 1.07 × 10-6 to 7.45 × 10-6 m3 kg-1 s-1). The NO emission potential for paddy field soils was about 1.2-2-fold higher than pasture soils. On the basis of laboratory results and field monitoring data of soil water content and soil temperature, the average NO fluxes from these saline sodic soils in the region were estimated to be 1.3-4.9 ng m-2 s-1 for an entire plant growth period. NO fluxes for pastures mainly occurred in the dry season and were about threefold higher than that for paddy fields, which was strongly influenced by field management.

  20. Cumulative soil chemistry changes from land application of saline-sodic waters

    Energy Technology Data Exchange (ETDEWEB)

    Ganjegunte, G.K.; King, L.A.; Vance, G.F. [University of Wyoming, Laramie, WY (United States). Department for Renewable Resources

    2008-09-15

    Management of large volumes (60,000 ha-m) of co-production water associated with coal bed natural gas (CBNG) water extraction is a potential concern in the Powder River Basin (PRB) of Wyoming and Montana due to elevated water salinity and sodicity levels. Land application of saline-sodic CBNG water is a common water management method being practiced in the PRB, which can result in deterioration in soil quality. The objective of this study was to evaluate effects from 1 to 4 yr of land application with CBNG water on soil chemical properties at six study sites (fine to loamy, mixed to smectitic, mesic, Ustic Ardisols and Entisols) in the Wyoming PRB region. Changes in chemistry of soils collected from six depths irrigated with CBNG water were compared with representative non-irrigated soils. Applications of CBNG water significantly increased soil EC, SAR, and ESP values (up to 21, 74, and 24 times, respectively) compared with non-irrigated soils. Differences in soil chemical properties between an irrigated and non-irrigated coarse-textured soil were less than that of fine-textured soils, emphasizing texture as an important factor for salinity buildup. Pretreatment of CBNG water using a sulfur burner and application of gypsum and elemental S soil amendments reduced soil pH but did not prevent the build-up of salts and sodium. Study results suggest that current CBNG water management strategies are not as effective as projected. Additional research is needed to develop management strategies appropriate for mitigating adverse effects of CBNG water irrigation.

  1. Cumulative soil chemistry changes from land application of saline-sodic waters.

    Science.gov (United States)

    Ganjegunte, Girisha K; King, Lyle A; Vance, George F

    2008-01-01

    Management of large volumes (60,000 ha-m) of co-production water associated with coal bed natural gas (CBNG) water extraction is a potential concern in the Powder River Basin (PRB) of Wyoming and Montana due to elevated water salinity and sodicity levels. Land application of saline-sodic CBNG water is a common water management method being practiced in the PRB, which can result in deterioration in soil quality. The objective of this study was to evaluate effects from 1 to 4 yr of land application with CBNG water on soil chemical properties at six study sites (fine to loamy, mixed to smectitic, mesic, Ustic Ardisols and Entisols) in the Wyoming PRB region. Changes in chemistry of soils collected from six depths irrigated with CBNG water were compared with representative nonirrigated soils. Applications of CBNG water significantly increased soil EC, SAR, and ESP values (up to 21, 74, and 24 times, respectively) compared with nonirrigated soils. Differences in soil chemical properties between an irrigated and nonirrigated coarse-textured soil were less than that of fine-textured soils, emphasizing texture as an important factor for salinity buildup. Pretreatment of CBNG water using a sulfur burner and application of gypsum and elemental S soil amendments reduced soil pH but did not prevent the build-up of salts and sodium. Study results suggest that current CBNG water management strategies are not as effective as projected. Additional research is needed to develop management strategies appropriate for mitigating adverse effects of CBNG water irrigation.

  2. Seasonal changes in salinity and sodicity of soils irrigated with treated domestic wastewater

    Science.gov (United States)

    Lado, Marcos; Ben-Hur, Meni

    2014-05-01

    Semiarid and arid zones are characterized by short wet winters and long dry summers, when most of crop production relies on irrigation. In these areas, treated wastewater (TWW) is a valuable water resource whose use is rapidly expanding. However, the composition of TWW differs from that of freshwater, mainly due to higher salt, sodium and organic matter concentrations. Therefore, its continuous application to the soil could have an impact on soil properties, particularly soil salinity and sodicity. However, these changes could be reverted during the following rainy season, if the amount of rain infiltrating through the soil is enough to leach salts down the profile. In the present study, we analyzed the effects of long-term irrigation with secondary TWW on salinity and sodicity of two contrasting soils under semiarid Mediterranean conditions. Experiments were conducted in two grapefruit orchards, one with a non-calcareous sandy soil (Typic Haploxeralf) and the other with a calcareous clayey soil (Chromic Haploxerert). Two treatments were tested (>7 years): (i) irrigation with freshwater and (ii) irrigation with domestic, secondary TTW. During the duration of the experiment, soil profiles were sampled at regular intervals to a depth of 1.2 m two times each year: i) in spring, before the irrigation season started, and ii) in fall, after irrigation ended and before the rainy season. The results show that, in general, irrigation with TWW increased soil salinity compared with freshwater in the upper 30 cm of the soil profiles. However, leaching by rainwater resulted in similar salinity values in both treatments after the rainy season. Soil sodicity increased with the irrigation with TWW to a depth 1.2 m in the sandy soil and 0.6 m in the clay soil, but in general, these changes did not disappear during the rainy season. It can be concluded that in semiarid regions with >500 mm annual rainfall, the precipitation can be sufficient to prevent long-term salt accumulation in

  3. Estimating soil salt components and salinity using hyperspectral remote sensing data in an arid area of China

    Science.gov (United States)

    Jiang, Hongnan; Shu, Hong; Lei, Lei; Xu, Jianhui

    2017-01-01

    HJ-1A hyperspectral data were used to distinguish topsoil salt components and estimate soil salinity, and the relationship between soil salt chemical components and sensitive bands of soil reflectance spectra was analyzed. The correlation between the soil salt content and the soil spectra obtained from the hyperspectral data was analyzed, proving that topsoil salinity has a very significant correlation with soil reflectance spectra. The relationship between soil reflectance spectra and salt chemical ions was investigated. The soil spectral reflectance at wavelength 510.975 nm and a difference vegetation index were selected to estimate soil salinity and the dominant salt chemical ion concentrations at a depth of 0 to 10 cm using a partial least squares regression model. It was found that the bands sensitive to various levels of chemical components of soil salt were shown to differ, controlled by the dominant component of the soil salt. The sensitive bands in the soil salinity estimation will change with differences in salt components. Estimating the dominant salt in the soil using soil reflectance spectra will lead to greater prediction accuracy. This study provided a possible method for the estimation of salinity and chemical component levels in topsoil, using the hyperspectral data to estimate topsoil salt components.

  4. Geochemical Modeling of Trivalent Chromium Migration in Saline-Sodic Soil during Lasagna Process: Impact on Soil Physicochemical Properties

    Directory of Open Access Journals (Sweden)

    Salihu Lukman

    2014-01-01

    Full Text Available Trivalent Cr is one of the heavy metals that are difficult to be removed from soil using electrokinetic study because of its geochemical properties. High buffering capacity soil is expected to reduce the mobility of the trivalent Cr and subsequently reduce the remedial efficiency thereby complicating the remediation process. In this study, geochemical modeling and migration of trivalent Cr in saline-sodic soil (high buffering capacity and alkaline during integrated electrokinetics-adsorption remediation, called the Lasagna process, were investigated. The remedial efficiency of trivalent Cr in addition to the impacts of the Lasagna process on the physicochemical properties of the soil was studied. Box-Behnken design was used to study the interaction effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil pH, electroosmotic volume, soil electrical conductivity, current, and remedial efficiency of trivalent Cr in saline-sodic soil that was artificially spiked with Cr, Cu, Cd, Pb, Hg, phenol, and kerosene. Overall desirability of 0.715 was attained at the following optimal conditions: voltage gradient 0.36 V/cm; polarity reversal rate 17.63 hr; soil pH 10.0. Under these conditions, the expected trivalent Cr remedial efficiency is 64.75 %.

  5. Geochemical modeling of trivalent chromium migration in saline-sodic soil during Lasagna process: impact on soil physicochemical properties.

    Science.gov (United States)

    Lukman, Salihu; Bukhari, Alaadin; Al-Malack, Muhammad H; Mu'azu, Nuhu D; Essa, Mohammed H

    2014-01-01

    Trivalent Cr is one of the heavy metals that are difficult to be removed from soil using electrokinetic study because of its geochemical properties. High buffering capacity soil is expected to reduce the mobility of the trivalent Cr and subsequently reduce the remedial efficiency thereby complicating the remediation process. In this study, geochemical modeling and migration of trivalent Cr in saline-sodic soil (high buffering capacity and alkaline) during integrated electrokinetics-adsorption remediation, called the Lasagna process, were investigated. The remedial efficiency of trivalent Cr in addition to the impacts of the Lasagna process on the physicochemical properties of the soil was studied. Box-Behnken design was used to study the interaction effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil pH, electroosmotic volume, soil electrical conductivity, current, and remedial efficiency of trivalent Cr in saline-sodic soil that was artificially spiked with Cr, Cu, Cd, Pb, Hg, phenol, and kerosene. Overall desirability of 0.715 was attained at the following optimal conditions: voltage gradient 0.36 V/cm; polarity reversal rate 17.63 hr; soil pH 10.0. Under these conditions, the expected trivalent Cr remedial efficiency is 64.75%.

  6. Enhancement of salinity tolerance in wheat through soil applied calcium carbide

    Directory of Open Access Journals (Sweden)

    Z. Ahmad

    2009-05-01

    Full Text Available Calcium carbide (CaC2 has been reported to increase growth and yield of crops under normal soil conditions. This study assessed its capacity to enhance salinity tolerance in wheat (Triticum aestivum L.; cv- 1076 under saline conditions. Three levels of salinity: 0, 7 and 12 dS m-1 were created using NaCl. Nitrogen, phosphorus and potassium were applied as ammonium sulphate and KH2PO4 at 50 and 25 mg kg-1 soil, respectively. The encapsulated calcium carbide (ECC at 45 mg kg-1 soil produced 1291.8 µmols of acetylene (C2H2 and 257.5 µmols of its product ethylene (C2H4 over a period of 80 days. The results of the pot study indicated that ECC increased the weight of spike, weight of grains per spike, length of spike, total water concentration, root/shoot ratio and relative leaf water content up to 17, 23, 22, 35, 33 and 3%, respectively, over the control. Contrary to this, salinity (at 12 dS m -1 decreased all these parameters up to 68, 60, 26, 30, 28 and 8%, respectively, compared to the control. These results indicate that ECC enhances salinity tolerance in wheat by improving uptake of nutrients through enhanced root growth, increased hydraulic conductivity and hormonal action of ethylene released by ECC. Total water concentration was positively correlated (0.73 with grains spike-1 at P ≤ 0.05

  7. Effect of Underground Saline Water on the Growth Characteristic of Tamarix austromongolica in Halomorphic Soil

    Science.gov (United States)

    Iwama, Kenji; Kobayashi, Koji; Kaneki, Ryoichi; Furukawa, Masayuki; Odani, Hiromichi

    It is important to evaluate the salt tolerance of native plants in order to utilize them for improving halomorphic soil in arid regions. Tamarix austromongolica, a dominant species in Inner Mongolia, China, has the property of salt absorption and expected soil desalinization. The effect of salt concentration in groundwater on the growth of stock diameter and shoot length were evaluated by cultivation experiments, growing the plants from cuttings for two years. Though the plants grew well in 1% salt concentration of groundwater, the evapotranspiration in the second year was reduced because of the growth of the root system. The growth of the plants and evapotranspiration were reduced with increasing groundwater salinity of 3 to 5%, but most plants did not die. In contrast, the plants which were supplied with groundwater of 7% salt concentration in the second year started to die in about a month, and two thirds of them died within five months. Thus the results showed that the tolerant limit of salinity of the plants in groundwater was 7%, and the growth was constrained with groundwater salinity of 3 to 5% concentration. The plants that survived with 7% salinity in the second year, however, were grown in groundwater salt concentration of 3% to 5% in the first year. This result indicated that saline stress might have changed the characteristic of salinity tolerance of the plant.

  8. Effect of irrigation with sea water on soil salinity and yield of oleic sunflower

    NARCIS (Netherlands)

    Farhadi Machekposhti, Mabood; Shahnazari, Ali; Ahmadi, Mirkhalegh Z.; Aghajani, Ghasem; Ritzema, Henk

    2017-01-01

    A field trial was carried out in 2013 and 2014 in a research field near Sari (Iran), to study the effect of irrigation with Caspian Sea water on soil salinity, growth parameters and yield components of oleic sunflower. The experiment was conducted with 4 levels of blending viz. 0% (S0)

  9. Impact Assessment of Salinization Affected Soil on Greenhouse Crops using SALTMED

    Science.gov (United States)

    Pappa, Polyxeni; Daliakopoulos, Ioannis; Tsanis, Ioannis; Varouchakis, Emmanouil

    2015-04-01

    Here we assess the effects of soil salinization on greenhouse crops and the potential benefits of rainwater harvesting as a soil amelioration technology. The study deals with the following scenarios: (a) variation of irrigation water salinity from 3,000 μS/cm to 500 μS/cm through mixing with rainwater, (b) crop substitution for increased tolerance and (c) climatic variability to account for the impact of climate change. In order to draw meaningful conclusions, a model that takes into account vegetation interaction, soil, irrigation water and climate variables is required. The SALTMED model is a reliable and tested physical process model that simulates evapotranspiration, plant water uptake, water and solute transport to estimate crop yield and biomass production under all irrigation systems. SALTMED is tested with the above scenarios in the RECARE FP7 Project Case Study of Timpaki, in the Island of Crete, Greece. Simulations are conducted for typical cultivations of Solanum lycopersicum, Capsicum anuumm and Solanum melongena. Preliminary results indicate the optimal combination from a set of solutions concerning the soil and water parameters can be beneficial against the salinization threat. Future research includes the validation of the results with field experiments. Keywords: salinization, greenhouse, tomato, SALTMED, rainwater, RECARE

  10. A new methodology for producing of risk maps of soil salinity, case ...

    African Journals Online (AJOL)

    The data for this study have been gathered from the records and reports published by the different departments of the Ministries of Agriculture and Energy and the Meteorological Organization of Iran. The present paper deals only with the intensities of hazards of soil salinity as a parameter for assessing the land degradation ...

  11. Reclamation of highly calcareous saline sodic soil using Atriplex halimus and by-product gypsum.

    Science.gov (United States)

    Gharaibeh, M A; Eltaif, N I; Albalasmeh, A A

    2011-10-01

    The removal of sodium salts from saline soils by salt tolerant crops, as alternative for costly chemical amendments, has emerged as an efficient low cost technology. Lysimeter experiments were carried out on a highly saline sodic soil (ECe = 65.3 dS m(-1), ESP = 27.4, CEC = 47.9 cmole+ kg(-1), and pH = 7.7) and irrigated with canal water (EC = 2.2 dSm(-1), SAR = 4.8) to investigate reclamation efficiency under four different treatments: control (no crop and no gypsum application) (C), gypsum application equivalent to 100% gypsum requirement (G100), planting sea orach (Atriplex halimus) as phytoremediation crop (Cr), planting sea orach with gypsum application equivalent to 50% gypsum requirement (CrG50). Soil salinity (ECe) and exchangeable sodium percentage (ESP) were significantly reduced compared to the control. Average ESP and ECe (dS m(-1)) in the top layer were 9.1, 5.8 (control), 4.8, 3.7 (Cr), 3.3, 3.9 (CrG50), and 3.8, 3.1 (G100), respectively. Atriplex halimus can be recommended as phytoremediation crop to reclaim highly saline sodic clay loam soils.

  12. Effect of soil salinity on the growth, amino acids and ion contents of ...

    African Journals Online (AJOL)

    jamil

    2012-10-25

    Oct 25, 2012 ... Effect of soil salinity on the growth, amino acids and ion contents of rice transgenic lines. Muhammad Jamil1*, Muhammad Anees2, Shafiq Ur Rehman3, Muhammad Daud Khan1,. Chang-Hyu Bae4, Sheong Chun Lee4 and Eui Shik Rha4. 1Department of Biotechnology and Genetic Engineering, Kohat ...

  13. A new methodology for producing of risk maps of soil salinity, Case ...

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    have been gathered from the records and reports published by the different departments of the Ministries of Agriculture and. Energy and the Meteorological Organization of Iran. The present paper deals only with the intensities of hazards of soil salinity as a parameter for assessing the land degradation. The present paper ...

  14. Monitoring soil coverage and yield of cowpea furrow irrigated with saline water

    Directory of Open Access Journals (Sweden)

    Antonia Leila Rocha Neves

    Full Text Available Abstract Cowpea crop is of great importance for northeast Brazil. The objective of this work was to evaluate the application of saline water in different developing stages on plant growth and changes in soil characteristics, measured by soil coverage, and on yield of cowpea plants. The experiment was conducted under field conditions, during the dry season in a completely randomized block design with five treatments and five replications. Each experimental unit consisted of 4 lines of plants with 5.0 m long. The treatments evaluated were: 1. irrigation with groundwater with electrical conductivity (ECw of 0.8 dS m-1 during the whole crop cycle; 2. saline water (5.0 dS m-1 during the whole crop cycle; 3, 4 and 5. saline water (5.0 dS m-1 up to 22nd, during 23rd to 42nd and from the 43rd to 62nd days after sowing, respectively, and groundwater in the remaining period. Soil coverage was evaluated by digital images using the software ENVI for image processing and classification. It was found that the continuous use of saline water inhibits plant growth, while irrigation with saline water during germination and initial growth stages caused retardation in plant development, but in this last case a recovery was observed in the final part of the experimental period. For treatments 2 and 3, a reduction was verified in the number of pods and in seed production, as compared to other treatments. Irrigation with saline water during 23 to 42 and 43 to 62 days after sowing did not affect reproductive and vegetative growth, but the saline water application in the pre-flowering (treatment 4 caused anticipation of the reproductive cycle.

  15. Regional-scale assessment of soil salinity in the Red River Valley using multi-year MODIS EVI and NDVI.

    Science.gov (United States)

    Lobell, D B; Lesch, S M; Corwin, D L; Ulmer, M G; Anderson, K A; Potts, D J; Doolittle, J A; Matos, M R; Baltes, M J

    2010-01-01

    The ability to inventory and map soil salinity at regional scales remains a significant challenge to scientists concerned with the salinization of agricultural soils throughout the world. Previous attempts to use satellite or aerial imagery to assess soil salinity have found limited success in part because of the inability of methods to isolate the effects of soil salinity on vegetative growth from other factors. This study evaluated the use of Moderate Resolution Imaging Spectroradiometer (MODIS) imagery in conjunction with directed soil sampling to assess and map soil salinity at a regional scale (i.e., 10-10(5) km(2)) in a parsimonious manner. Correlations with three soil salinity ground truth datasets differing in scale were made in Kittson County within the Red River Valley (RRV) of North Dakota and Minnesota, an area where soil salinity assessment is a top priority for the Natural Resource Conservation Service (NRCS). Multi-year MODIS imagery was used to mitigate the influence of temporally dynamic factors such as weather, pests, disease, and management influences. The average of the MODIS enhanced vegetation index (EVI) for a 7-yr period exhibited a strong relationship with soil salinity in all three datasets, and outperformed the normalized difference vegetation index (NDVI). One-third to one-half of the spatial variability in soil salinity could be captured by measuring average MODIS EVI and whether the land qualified for the Conservation Reserve Program (a USDA program that sets aside marginally productive land based on conservation principles). The approach has the practical simplicity to allow broad application in areas where limited resources are available for salinity assessment.

  16. Regional scale soil salinity assessment using remote sensing based environmental factors and vegetation indicators

    Science.gov (United States)

    Ma, Ligang; Ma, Fenglan; Li, Jiadan; Gu, Qing; Yang, Shengtian; Ding, Jianli

    2017-04-01

    Land degradation, specifically soil salinization has rendered large areas of China west sterile and unproductive while diminishing the productivity of adjacent lands and other areas where salting is less severe. Up to now despite decades of research in soil mapping, few accurate and up-to-date information on the spatial extent and variability of soil salinity are available for large geographic regions. This study explores the po-tentials of assessing soil salinity via linear and random forest modeling of remote sensing based environmental factors and indirect indicators. A case study is presented for the arid oases of Tarim and Junggar Basin, Xinjiang, China using time series land surface temperature (LST), evapotranspiration (ET), TRMM precipitation (TRM), DEM product and vegetation indexes as well as their second order products. In par-ticular, the location of the oasis, the best feature sets, different salinity degrees and modeling approaches were fully examined. All constructed models were evaluated for their fit to the whole data set and their performance in a leave-one-field-out spatial cross-validation. In addition, the Kruskal-Wallis rank test was adopted for the statis-tical comparison of different models. Overall, the random forest model outperformed the linear model for the two basins, all salinity degrees and datasets. As for feature set, LST and ET were consistently identified to be the most important factors for two ba-sins while the contribution of vegetation indexes vary with location. What's more, models performances are promising for the salinity ranges that are most relevant to agricultural productivity.

  17. Vegetation response to soil salinity and waterlogging in three saltmarsh hydrosequences through macronutrients distribution

    Science.gov (United States)

    Ferronato, Chiara; Speranza, Maria; Ferroni, Lucia; Buscaroli, Alessandro; Vianello, Gilmo; Vittori Antisari, Livia

    2018-01-01

    Saltmarshes consist of soil hydrosequences, where the complex interactions between water tide fluctuations, soil physicochemical properties and plant colonization contribute to the triggering of the pedogenetic processes and consequently to the stability of the saltmarsh edges. In this study, the composition and richness of the vegetation cover were investigated along soil transects in three different saltmarshes. With the aim to investigate the response of the vegetation to the soil hydroperiod and its influence on the availability of soil nutrients, plant and soil samples were collected in four representative sites on each saltmarsh transect (hydrosequence). Among the different species of saltmarshes, L. vulgare and S. europaea colonized intertidal areas, where an accumulation of nutrients (Ca, K, P, S and Na) and organic C and total N (OC and TN, respectively) was found. These intertidal areas are the "critical transition zones", which drive the transition between the terrestrial and the aquatic systems along the increase of soil salinity and water saturation. Among the different element cycles analysed in the soil-plant system, the analysis of the Na and S dynamic, through both bioconcentration and translocation indexes, explains the different adaptation mechanisms to different salinity and waterlogging stressors. The limiting of the species areal was generally associated firstly with a decrease in their Na and S bioconcentration factor and, to a lesser extent, with the increase in their Na and S translocation.

  18. [Effects of non-sufficient irrigation with saline water on soil water-salt distribution and spring corn yield].

    Science.gov (United States)

    Jiang, Jing; Feng, Shao-yuan; Sun, Zhen-hua; Huo, Zai-lin

    2008-12-01

    A field experiment was conducted to study the effects of sufficient and non-sufficient irrigation with saline water on the soil water-salt distribution and spring corn yield in the middle reach of Shiyanghe River Basin. The results showed that under both sufficient and non-sufficient irrigation, the peak value of soil water content all appeared during irrigation period, and the variation range of the water content was higher under sufficient than under non-sufficient irrigation. Soil salinity was positively correlated with the salinity of irrigation water. At the same salinity of irrigation water, the soil salinity under non-sufficient irrigation was lower than that under sufficient irrigation. Under non-sufficient irrigation, the soil layer with salt accumulation was moved up, but the water and salt contents in 80-100 cm soil layer were less affected by the amount and salinity of irrigation water. Comparing with that under fresh water irrigation, the spring corn yield under saline water irrigation was decreased by 15%-22%. Under non-sufficient irrigation with 9 g x L(-1), 6 g x L(-1), and 3 g x L(-1) of saline water, the average salt content in 1 m soil layer after harvest was decreased by 8.1%, 12.4%, and 18.4%, and the corn yield was only decreased by 3.4%, 6.8%, and 3.0%, respectively, compared with those under sufficient irrigation.

  19. Influence of salinity on soil chemical properties and surrounding ...

    African Journals Online (AJOL)

    The exchangeable sodium percentage (ESP), cation exchange capacity (CEC) and sodium adsorption ratio (SAR) were calculated. No plant was found growing on the salt mining site (SMS) unlike the control site (CTS) which has a little diversity of plants. The soil organic carbon, organic magnesium, total nitrogen and ...

  20. Effects of 10-year management regimes on the soil seed bank in saline-alkaline grassland.

    Science.gov (United States)

    Ma, Hongyuan; Yang, Haoyu; Liang, Zhengwei; Ooi, Mark K J

    2015-01-01

    Management regimes for vegetation restoration of degraded grasslands can significantly affect the process of ecological succession. However, few studies have focused on variation in the soil seed bank during vegetation restoration under different management regimes, especially in saline-alkaline grassland habitats. Our aim was to provide insights into the ecological effects of grassland management regimes on soil seed bank composition and vegetation establishment in mown, fenced, transplanted and natural grassland sites, all dominated by the perennial rhizomatous grass Leymus chinensis. We studied species composition and diversity in both the soil seed bank and aboveground vegetation in differently managed grasslands in Northeast China. An NMDS (nonmetric multidimensional scaling) was used to evaluate the relationship between species composition, soil seed banks, aboveground vegetation and soil properties. Fenced and mown grassland sites had high density and species richness in both the soil seed bank and aboveground vegetation. The Transplanted treatment exhibited the highest vegetation growth and seed production of the target species L. chinensis. Seeds of L. chinensis in the soil occurred only in transplanted and natural grassland. Based on the NMDS analysis, the number of species in both the soil seed bank and aboveground vegetation were significantly related to soil Na+, Cl-, RSC (residual sodium carbonate), alkalinity, ESP (exchangeable sodium percentage) and AP (available phosphorus). Soil seed bank composition and diversity in the saline-alkaline grassland were significantly affected by the management regimes implemented, and were also significantly related to the aboveground vegetation and several soil properties. Based on vegetative growth, reproductive output and maintenance of soil seed bank, the transplanting was identified as the most effective method for relatively rapid restoration of the target species L. chinensis. This approach could be

  1. The effect of biofertilizer fungi on Ciherang rice growth at some level of soil salinity

    Directory of Open Access Journals (Sweden)

    Y B Subowo

    2014-04-01

    Full Text Available A research about the effect of fungus contained biofertilizer on Ciherang rice that was growth on different level of soil salinity was conducted. One of the effect of global climate changes is the increase of sea water level. It leads to the expansion of sea water submerged land for agriculture. Salt intrution to the agriculture area considerably decrease soil fertility because of the high salinity. Some of microbes especially soil fungi such as Aspergillus sp and Penicillium sp. are able to grow at high salinity environment. Those fungi were also able to degrade lignocellulose, sollubilize in organic phosphate and provide organic phosphat and produce plant growth hormon especially IAA. Such activities benefit to improve soil fertility in high salinity land as a bio-fertilizer.The objective of this research was to know the growth of rice plant that treated with fungus contained bio-fertilizer on land with different level of salinity. The rice were planted in Green house of Cibinong Science Centre, Cibinong.The research was set up as complete random design with five replication. The rice were watered by 5 conditions: 50% of sea water, 100% of sea water, 100% sea water + 2 % NaCl , fresh water + 5 % NaCl and 100% fresh water as the control. Fertilizer was added to the medium twice. Ten grams of fertilizer were used per polybag (10g/7 Kg, 2 weeks after planting and before flowering subsequently. The observed parameters were plant height, number of tiller, leaves colour, biomass dry weight, soil organic carbon content, cellulosic and lignin degrading activities of the fungus, fungus phosphate-solubilizing potency and fungus production of IAA.The watering treatment lead to 5 level of salinity i.e. : 5,93 dS/m (50% sea water, 9,15 dS/m (100% sea water, 10,42 dS/m (sea water + 2% NaCl, 12,43 dS/m (fresh water + 5% NaCl and 0,74 dS/m (fresh water. The result showed that among those 5 watering condition, the rice grew best on 5,93 dS/m (watering 50% of

  2. Laboratory Salinization of Brazilian Alluvial Soils and the Spectral Effects of Gypsum

    Directory of Open Access Journals (Sweden)

    Luis Clenio J. Moreira

    2014-03-01

    Full Text Available Irrigation-induced salinization is an important land degradation process that affects crop yield in the Brazilian semi-arid region, and gypsum has been used as a corrective measure for saline soils. Fluvent soil samples (180 were treated with increasing levels of salinization of NaCl, MgCl2 and CaCl2. The salinity was gauged using electrical conductivity (EC. Gypsum was added to one split of these samples before they were treated by the saline solutions. Laboratory reflectance spectra were measured at nadir under a controlled environment using a FieldSpec spectrometer, a 250-W halogen lamp and a Spectralon panel. Variations in spectral reflectance and brightness were evaluated using principal component analysis, as well as the continuum-removed absorption depths of major features at 1450, 1950, 1750 and 2200 nm for both the gypsum-treated (TG and non-treated (NTG air-dried soil samples as a function of EC. Pearson’s correlation coefficients of reflectance and the band depth with EC were also obtained to establish the relationships with salinity. Results showed that NTG samples presented a decrease in reflectance and brightness with increasing CaCl2 and MgCl2 salinization. The reverse was observed for NaCl. Gypsum increased the spectral reflectance of the soil. The best negative correlations between reflectance and EC were observed in the 1500–2400 nm range for CaCl2 and MgCl2, probably because these wavelengths are most affected by water absorption, as Ca and Mg are much more hygroscopic than Na. These decreased after chemical treatment with gypsum. The most prominent features were observed at 1450, 1950 and 1750 nm in salinized-soil spectra. The 2200-nm clay mineral absorption band depth was inversely correlated with salt concentration. From these features, only the 1750 and 2200 nm ones are within atmospheric absorption windows and can be more easily measured using hyperspectral sensors.

  3. Effects of different remediation treatments on crude oil contaminated saline soil.

    Science.gov (United States)

    Gao, Yong-Chao; Guo, Shu-Hai; Wang, Jia-Ning; Li, Dan; Wang, Hui; Zeng, De-Hui

    2014-12-01

    Remediation of the petroleum contaminated soil is essential to maintain the sustainable development of soil ecosystem. Bioremediation using microorganisms and plants is a promising method for the degradation of crude oil contaminants. The effects of different remediation treatments, including nitrogen addition, Suaeda salsa planting, and arbuscular mycorrhiza (AM) fungi inoculation individually or combined, on crude oil contaminated saline soil were assessed using a microcosm experiment. The results showed that different remediation treatments significantly affected the physicochemical properties, oil contaminant degradation and bacterial community structure of the oil contaminated saline soil. Nitrogen addition stimulated the degradation of total petroleum hydrocarbon significantly at the initial 30d of remediation. Coupling of different remediation techniques was more effective in degrading crude oil contaminants. Applications of nitrogen, AM fungi and their combination enhanced the phytoremediation efficiency of S. salsa significantly. The main bacterial community composition in the crude oil contaminated saline soil shifted with the remediation processes. γ-Proteobacteria, β-Proteobacteria, and Actinobacteria were the pioneer oil-degraders at the initial stage, and Firmicutes were considered to be able to degrade the recalcitrant components at the later stage. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Reclamation of highly calcareous saline-sodic soil using low quality water and phosphogypsum

    Science.gov (United States)

    Gharaibeh, M. A.; Rusan, M. J.; Eltaif, N. I.; Shunnar, O. F.

    2014-09-01

    The efficiency of two amendments in reclaiming saline sodic soil using moderately saline (EC) and moderate sodium adsorption ratio (SAR) canal water was investigated. Phosphogypsum (PG) and reagent grade calcium chloride were applied to packed sandy loam soil columns and leached with canal water (SAR = 4, and EC = 2.16 dS m-1). Phosphogypsum was mixed with top soil prior to leaching at application rates of 5, 10, 15, 20, 25, 35, 40 Mg ha-1, whereas calcium chloride was dissolved directly in water at equivalent rates of 4.25, 8.5, 12.75, 17.0, 21.25, 29.75, and 34 Mg ha-1, respectively. Both amendments efficiently reduced soil salinity and sodicity. Calcium chloride removed 90 % of the total Na and soluble salts whereas PG removed 79 and 60 %, respectively. Exchangeable sodium percentage was reduced by 90 % in both amendments. Results indicated that during cation exchange reactions most of the sodium was removed when effluent SAR was at maximum. Phosphogypsum has lower total costs than calcium chloride and as an efficient amendment an application of 30 Mg ha-1 and leaching with 4 pore volume (PV) of canal water could be recommended to reclaim the studied soil.

  5. Use of gypsum residues as a corrective for saline-sodic soil

    Directory of Open Access Journals (Sweden)

    Paulo Medeiros dos Santos

    2014-03-01

    Full Text Available One of the hugest problems faced by the civil construction sector is the final destination of residues, especially gypsum, which presents recycling restrictions. However, these residues present a high amount of calcium in their composition, and can be alternatively used for replacing mined gypsum as a saline-sodic soil corrective. This study aimed at evaluating the efficiency of gypsum residues from the civil construction, when compared to mined gypsum, for correcting a saline-sodic soil. A randomized blocks design was used, in a factorial arrangement consisting of two kinds of corrective (gypsum residue and mined gypsum and five leaching depths (0.5, 1.0, 1.5, 2.0 and 2.5 times the soil pores volume, with three replications. Electric conductivity, soluble cations and sodium adsorption ratio were evaluated in the soil saturation extract. The use of gypsum residue proved to be effective in leaching salts and soluble sodium in saline-sodic soil, and can be recommended as a calcium source for recovering from sodicity.

  6. Leaf gas exchange in cowpea and CO2 efflux in soil irrigated with saline water

    Directory of Open Access Journals (Sweden)

    Wanderson J. de Oliveira

    Full Text Available ABSTRACT Leaf gas exchanges in plants and soil respiration are important tools for assessing the effects of salinity on the soil-plant system. An experiment was conducted with cowpea irrigated with saline water (0, 2.5, 5.0, 7.5, 10.0 and 12.5 dS m-1 prepared with two sources: NaCl and a mixture of Ca, Mg, Na, K and Cl ions in a randomized block design and a 6 x 2 factorial scheme, with four replicates, totaling 48 experimental plots. At 20 days after planting (DAP, plants were evaluated for net photosynthesis (A, stomatal conductance (gs and transpiration (E using the Infra-Red Gas Analyzer (Model XT6400- LICOR, and water use efficiency, intrinsic water use efficiency and instantaneous efficiency of carboxylation were calculated. At 60 DAP, the soil CO2 efflux (soil respiration was determined with a camera (Model 6400-09- LICOR. Salinity caused reductions in A, gs and E. However, the salt source did not have significant effect on these variables. Soil CO2 efflux was reduced with the increase in the electrical conductivity, especially in the mixture of ions.

  7. Predicted Infiltration for Sodic/Saline Soils from Reclaimed Coastal Areas: Sensitivity to Model Parameters

    Science.gov (United States)

    She, Dongli; Yu, Shuang'en; Shao, Guangcheng

    2014-01-01

    This study was conducted to assess the influences of soil surface conditions and initial soil water content on water movement in unsaturated sodic soils of reclaimed coastal areas. Data was collected from column experiments in which two soils from a Chinese coastal area reclaimed in 2007 (Soil A, saline) and 1960 (Soil B, nonsaline) were used, with bulk densities of 1.4 or 1.5 g/cm3. A 1D-infiltration model was created using a finite difference method and its sensitivity to hydraulic related parameters was tested. The model well simulated the measured data. The results revealed that soil compaction notably affected the water retention of both soils. Model simulations showed that increasing the ponded water depth had little effect on the infiltration process, since the increases in cumulative infiltration and wetting front advancement rate were small. However, the wetting front advancement rate increased and the cumulative infiltration decreased to a greater extent when θ 0 was increased. Soil physical quality was described better by the S parameter than by the saturated hydraulic conductivity since the latter was also affected by the physical chemical effects on clay swelling occurring in the presence of different levels of electrolytes in the soil solutions of the two soils. PMID:25197699

  8. Predicted Infiltration for Sodic/Saline Soils from Reclaimed Coastal Areas: Sensitivity to Model Parameters

    Directory of Open Access Journals (Sweden)

    Dongdong Liu

    2014-01-01

    Full Text Available This study was conducted to assess the influences of soil surface conditions and initial soil water content on water movement in unsaturated sodic soils of reclaimed coastal areas. Data was collected from column experiments in which two soils from a Chinese coastal area reclaimed in 2007 (Soil A, saline and 1960 (Soil B, nonsaline were used, with bulk densities of 1.4 or 1.5 g/cm3. A 1D-infiltration model was created using a finite difference method and its sensitivity to hydraulic related parameters was tested. The model well simulated the measured data. The results revealed that soil compaction notably affected the water retention of both soils. Model simulations showed that increasing the ponded water depth had little effect on the infiltration process, since the increases in cumulative infiltration and wetting front advancement rate were small. However, the wetting front advancement rate increased and the cumulative infiltration decreased to a greater extent when θ0 was increased. Soil physical quality was described better by the S parameter than by the saturated hydraulic conductivity since the latter was also affected by the physical chemical effects on clay swelling occurring in the presence of different levels of electrolytes in the soil solutions of the two soils.

  9. Predicted infiltration for sodic/saline soils from reclaimed coastal areas: sensitivity to model parameters.

    Science.gov (United States)

    Liu, Dongdong; She, Dongli; Yu, Shuang'en; Shao, Guangcheng; Chen, Dan

    2014-01-01

    This study was conducted to assess the influences of soil surface conditions and initial soil water content on water movement in unsaturated sodic soils of reclaimed coastal areas. Data was collected from column experiments in which two soils from a Chinese coastal area reclaimed in 2007 (Soil A, saline) and 1960 (Soil B, nonsaline) were used, with bulk densities of 1.4 or 1.5 g/cm(3). A 1D-infiltration model was created using a finite difference method and its sensitivity to hydraulic related parameters was tested. The model well simulated the measured data. The results revealed that soil compaction notably affected the water retention of both soils. Model simulations showed that increasing the ponded water depth had little effect on the infiltration process, since the increases in cumulative infiltration and wetting front advancement rate were small. However, the wetting front advancement rate increased and the cumulative infiltration decreased to a greater extent when θ₀ was increased. Soil physical quality was described better by the S parameter than by the saturated hydraulic conductivity since the latter was also affected by the physical chemical effects on clay swelling occurring in the presence of different levels of electrolytes in the soil solutions of the two soils.

  10. Plant-Microbe Interactions and Water Management in Arid and Saline Soils

    KAUST Repository

    Daffonchio, Daniele

    2014-12-05

    Drought and salinity are major factors limiting agriculture in many regions in the world, and their importance is predicted to even increase in the near future in parallel with the ongoing global warming and climate changes. Soil and rhizosphere microbes are potential resources for counteracting such abiotic stresses in plants. The knowledge on the roles of root microorganisms in retaining soil humidity and promoting plant growth under such abiotic stresses is analyzed in this chapter. The importance of microbial diversity in the rhizosphere for alleviating drought and salinity effects on the plant physiology is discussed in the light of “Desert Farming”, the general crop management practice that is frequently used in arid regions. The plant growth promoting functional services exerted by microorganisms within the rhizosphere in arid soils are presented in relation to the plant response under water stress.

  11. Salinization of the soil solution decreases the further accumulation of salt in the root zone of the halophyte Atriplex nummularia Lindl. growing above shallow saline groundwater.

    Science.gov (United States)

    Alharby, Hesham F; Colmer, Timothy D; Barrett-Lennard, Edward G

    2018-01-01

    Water use by plants in landscapes with shallow saline groundwater may lead to the accumulation of salt in the root zone. We examined the accumulation of Na+ and Cl- around the roots of the halophyte Atriplex nummularia Lindl. and the impacts of this increasing salinity for stomatal conductance, water use and growth. Plants were grown in columns filled with a sand-clay mixture and connected at the bottom to reservoirs containing 20, 200 or 400 mM NaCl. At 21 d, Na+ and Cl- concentrations in the soil solution were affected by the salinity of the groundwater, height above the water table and the root fresh mass density at various soil depths (P groundwater salinity and height above the water table remained significant factors, but the root fresh mass density was no longer significant. Regression of data from the 200 and 400 mM NaCl treatments showed that the rate of Na+ accumulation in the soil increased until the Na+ concentration reached ~250 mM within the root zone; subsequent decreases in accumulation were associated with decreases in stomatal conductance. Salinization of the soil solution therefore had a feedback effect on further salinization within the root zone. © 2017 John Wiley & Sons Ltd.

  12. Leaching and reclamation of a biochar and compost amended saline-sodic soil with moderate SAR reclaimed water

    OpenAIRE

    Chaganti, VN; Crohn, DM; Šimůnek, J

    2015-01-01

    © 2015 Elsevier B.V. Remediating saline-sodic soils with organic amendments is increasingly seen as a cheaper and sustainable alternative to inorganic materials. The reclamation potential of biochar, biosolids and greenwaste composts applied to a saline-sodic soil was evaluated in a laboratory leaching experiment using moderate SAR reclaimed water. Treatments included biochar, biosolids co-compost, greenwaste compost (all applied at a 75tha -1 rate), gypsum (50% soil gypsum ...

  13. Effect of various soil salinity level on the antioxidant and physiological properties of corn plant (Zea mays)

    OpenAIRE

    Ramin Ezzati; Mina Karimi

    2015-01-01

    To study the effect of various soil salinity levels on the antioxidant enzymes and physiological characteristics of corn as an indicator of salt stress resistance, present study was conducted in 2013 at Research lab of environmental, Faculty of Biological Sciences, University of Kharazmi, Iran. Furthermore, desert soils of Libya, India, Iraq and Karaj were used for testing the effect of soil salinity on the quantity of oxidant enzymes and various properties of maize plant. For pro...

  14. Scaling Leaves to Fluxes in a Well-Watered Saline Soil Peatlands

    Science.gov (United States)

    Runkle, B.; Liang, X.; Dracup, J.; Detto, M.; Baldocchi, D.

    2008-12-01

    This study investigates the role of soil salinity in modifying land surface fluxes in a California Bay-Delta peatlands pasture. It combines leaf gas exchange and soil salinity measurements in a soil-vegetation- atmosphere transfer model to move from the plant scale to the footprint of an eddy covariance tower. The close match between measured and modeled daytime carbon and water fluxes encourages numerical analyses and predictions for assessing the separate and joint effects of various drivers of and responses to climate change. The model examines the role of temperature, carbon dioxide concentration, soil water content, and soil salinity levels on the fundamental fluxes of carbon and water between the surface and the atmosphere. Incorporating both leaf gas exchange parameters and responses to soil salinity in the model are shown to be critical to accurate assessments of the diurnal cycles of the fluxes. Only by incorporating both sets of knowledge into the model are proper estimates of water use efficiency guaranteed. The model and data reveal, through rigorous sensitivity analysis, the resilience of the dominant landscape cover, Lepidium latifolium, to the drivers of and responses to climate change. This research is useful to regional water resources and land management planners, as the landscape is capable of generating very high evapotranspiration rates (up to 5 mm per day). Moreover, this land cover species is considered by the California Department of Agriculture a species of concern due to its ability to expand widely and create dense mono-specific stands that exclude other plants and impact the native ecological and agricultural plant communities. Understanding its response to climate change will be of critical importance in accurately assessing its control.

  15. Salinity management using an anionic polymer in a pecan field with calcareous-sodic soil.

    Science.gov (United States)

    Ganjegunte, Girisha K; Sheng, Zhuping; Braun, Robert J

    2011-01-01

    Soil salinity and sodicity have long been recognized as the major concerns for irrigated agriculture in the Trans-Pecos Basin, where fields are being flood irrigated with Rio Grande River water that has elevated salinity. Reclamation of these salt-affected lands is difficult due to fine-texture, high shrink-swell soils with low permeability. Conventional practice of subsoiling to improve soil permeability is expensive and has had limited success on the irrigated soils that have appreciable amounts of readily weatherable Ca minerals. If these native Ca sources can be effectively used to counter sodicity, it can improve soil permeability and reduce amelioration costs. This study evaluated the effects of 3 yr of polyacrylamide (PAM) application at 10 mg L concentration during the first irrigation of the season to evaluate soil permeability, in situ Ca mineral dissolution, and leaching of salts from the effective root zone in a pecan field of El Paso County, TX. Results indicated that PAM application improved water movement throughout the effective root zone that resulted in Na leaching. Polymer application significantly decreased CaCO (estimated based on inorganic C analysis) concentrations in the top 45 cm compared with baseline levels, indicating solubilization and redistribution of calcite. The PAM application also reduced soil electrical conductivity (EC) in the top 60 cm (4.64-2.76 dS m) and sodium adsorption ratio (SAR) from 13.1 to 5.7 mmol L in the top 75-cm depths. As evidence of improved soil conditions, pecan nut yields increased by 34% in PAM-treated fields over the control. Results suggested that PAM application helped in effective use of native Ca sources present in soils of the study site and reduced Na by improving soil permeability. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  16. Microbialproperty improvement of saline-alkali soil for vegetable cultivation in Shanghai coastal area and its evaluation

    Directory of Open Access Journals (Sweden)

    KOU Yiming

    2015-10-01

    Full Text Available In order to improve the fertility of saline-alkali soil in Shanghai coastal area,and make it suitable for vegetable cultiration,in the study,the saline-alkali soil was mixed with organic fertilizer,and then sprayed with composite microbes,which have the ability of the synergistically degrading organic substrate.The results showed that the saline-alkali soil added with 5∶1 organic fertilizer can rapidly increase the utilization ability soil organic matter.The soil microbial populations and microbial diversity index were significantly improved when applied with the 0.5% composite microbial liquid which containeds 1∶3∶3∶1 of Bacillus licheniformis,Pseudomonas sp., Flavobacterium sp.and Sphingomonas sp..At the same time,the enzymology indicators of soil urease,phosphatase,cellulase and catalase increased significantly.The vegetable cultivation experiments showed that:the biomass of Brassica chinensis nearly doubled in the original saline-alkali soil,while the yield of organic fertilizer increased 30.2% after 50 days.The research result on of the biological improvement for saline-alkali soil will have good application value in vegetable planting in coastal saline-alkali soil.

  17. Soil salinity estimation using RADARSAT 2 polarimetric data in arid and sub-arid regions: Morocco and Tunisia cases.

    Science.gov (United States)

    Lhissou, Rachid; Chokmani, Karem; El Harti, Abderrazak; Abdelfattah, Riadh; Barbouchi, Meriem; Ben Aissa, Nadhira

    2013-04-01

    Soil salinity is a serious environmental hazard that affects nearly 7% of the earth's surface. In Morocco and Tunisia, soil salinity affects 5% and 8% of their total area respectively. Affected areas are exposed to an overuse of renewable water resources and a chronic decline of groundwater levels. Therefore, problems of soil salinization are severe. Salinization causes negative effects on the ground; it affects agricultural production, infrastructure, water resources and biodiversity. Experimental methods for monitoring soil salinity by direct measurements in situ are very demanding of time and resources, and also very limited in terms of spatial coverage. Several studies have described the usefulness of remote sensing for mapping salinity. In fact, radar remote sensing can be an interesting tool for mapping and monitoring soil salinization by its synoptic coverage and the sensitivity of the radar signal to soil parameters at the first five centimeters of surface. The radar remote sensing could be more interesting than optical data as the soil salinity depends on the moisture variability. This study develops the potential of RADARSAT-2 polarimetric SAR data for soil salinity estimation in Tadla plain (central Morocco) and Mahdia region (Central Tunisia). These two test sites are different in their soil compositions as well as in their surface occupations. This was done in the object to compare the behavior of the radar backscattering with respect to the soil salinity variation in different environment. RADARSAT-2 data were acquired in full polarization at a rate of three acquisitions in FQ9 angular mode over Tadla plain and three acquisitions in FQ7 angular mode over Mahdia region. Based on field measurement data of electrical conductivity collected in three field campaigns over three dates simultaneously with acquisition periods of SAR satellite images, and polarimetric parameters, a two model calibration techniques are used to develop a soil salinity estimation

  18. Implementation of New Technologies of Chemical and Phytomelioration of Acidic and Saline Soils

    Directory of Open Access Journals (Sweden)

    Zaimenko, N.V.

    2016-01-01

    Full Text Available The newest technology of reclamation of acid and saline soils, based on the integrated use of silicon compounds with cultivation of cereals, legumes and cruciferous plant species was implemented. The technological regulations for the use of chemical and phytomeliorants in different soil-climatic zones of Ukraine were worked out. The silicone-containing mixtures with a high meliorative potential and the optimal dosages for their application were determined. A comprehensive study of the chemical and phytomeliorants was conducted; their role in stimulation of the development of agriculturally useful microbiota, reducing soil sickness, increasing of the plant adaptive potential to abiotic stress factors was defined. Application of silicon-containing mixtures improved agrophysical, agrochemical, biological characteristics of soil, reduced its toxicity and soil sickness. The structure of crop rotation was improved.

  19. [Monitoring of soil salinization in Northern Tarim Basin, Xinjiang of China in dry and wet seasons based on remote sensing].

    Science.gov (United States)

    Yao, Yuan; Ding, Jian-Li; Zhang, Fang; Wang, Gang; Jiang, Hong-Nan

    2013-11-01

    Soil salinization is one of the most important eco-environment problems in arid area, which can not only induce land degradation, inhibit vegetation growth, but also impede regional agricultural production. To accurately and quickly obtain the information of regional saline soils by using remote sensing data is critical to monitor soil salinization and prevent its further development. Taking the Weigan-Kuqa River Delta Oasis in the northern Tarim River Basin of Xinjiang as test object, and based on the remote sensing data from Landsat-TM images of April 15, 2011 and September 22, 2011, in combining with the measured data from field survey, this paper extracted the characteristic variables modified normalized difference water index (MNDWI), normalized difference vegetation index (NDVI), and the third principal component from K-L transformation (K-L-3). The decision tree method was adopted to establish the extraction models of soil salinization in the two key seasons (dry and wet seasons) of the study area, and the classification maps of soil salinization in the two seasons were drawn. The results showed that the decision tree method had a higher discrimination precision, being 87.2% in dry season and 85.3% in wet season, which was able to be used for effectively monitoring the dynamics of soil salinization and its spatial distribution, and to provide scientific basis for the comprehensive management of saline soils in arid area and the rational utilization of oasis land resources.

  20. Spatial modeling of soil salinity using remote sensing, GIS, and field data

    Science.gov (United States)

    Eldeiry, Ahmed Aly Mohamed

    In this study a new methodology was developed to generate accurate predicted soil salinity maps using remote sensing data. The techniques used include integrating field data, geographic information systems (GIS), remote sensing, and spatial modelling techniques. Corn and alfalfa crops were selected as indicators of soil salinity during 2001 and 2004 respectively. Five images were acquired from Aster, Ikonos, and Landsat to check the correlation between measured soil salinity and remote sensing data. Observed data from four corn fields during 2001 and four alfalfa fields during 2004 were used in conjunction with the Aster, Ikonos, and Landsat images. Three subsets of 75%, 50%, and 25% were randomly selected from each main set of observed data to be used in conjunction with the Ikonos and Landsat images. Three models were applied to predict soil salinity from remote sensing: the ordinary least squares model (OLS), spatial autoregressive model (SAR), and modified kriging model. The combination of satellite imagery bands that had the best correlation with measured soil salinity was used to predict soil salinity. A number of criteria were used to select the best model. The results show that the modified kriging model provides the best results over the OLS and the SAR models. The OLS model meets the model selection criteria, but, in most cases, it involves some autocorrelation among the residuals. The SAR model was able to remove some of the autocorrelation among the residuals, but the R2 was reduced. The R 2 values of the OLS model were 0.34, 0.47, 0.52, 0.26, and 0.37 for the 2001 Aster, Landsat, Ikonos images for corn, the 2004 Landsat and Ikonos image for alfalfa respectively. The R2 values of the SAR model were 0.05, 0.18, 0.25. 0.03, and 0.15 for the same images. The R2 values of the modified kriging model were 0.81, 0.83, 0.91, 0.60 and 0.68 for the same images. Also, the mean absolute error (MAE) improved significantly when using modified kriging over the OLS and

  1. ESA's Soil Moisture dnd Ocean Salinity Mission - Contributing to Water Resource Management

    Science.gov (United States)

    Mecklenburg, S.; Kerr, Y. H.

    2015-12-01

    The Soil Moisture and Ocean Salinity (SMOS) mission, launched in November 2009, is the European Space Agency's (ESA) second Earth Explorer Opportunity mission. The scientific objectives of the SMOS mission directly respond to the need for global observations of soil moisture and ocean salinity, two key variables used in predictive hydrological, oceanographic and atmospheric models. SMOS observations also provide information on the characterisation of ice and snow covered surfaces and the sea ice effect on ocean-atmosphere heat fluxes and dynamics, which affects large-scale processes of the Earth's climate system. The focus of this paper will be on SMOS's contribution to support water resource management: SMOS surface soil moisture provides the input to derive root-zone soil moisture, which in turn provides the input for the drought index, an important monitoring prediction tool for plant available water. In addition to surface soil moisture, SMOS also provides observations on vegetation optical depth. Both parameters aid agricultural applications such as crop growth, yield forecasting and drought monitoring, and provide input for carbon and land surface modelling. SMOS data products are used in data assimilation and forecasting systems. Over land, assimilating SMOS derived information has shown to have a positive impact on applications such as NWP, stream flow forecasting and the analysis of net ecosystem exchange. Over ocean, both sea surface salinity and severe wind speed have the potential to increase the predictive skill on the seasonal and short- to medium-range forecast range. Operational users in particular in Numerical Weather Prediction and operational hydrology have put forward a requirement for soil moisture data to be available in near-real time (NRT). This has been addressed by developing a fast retrieval for a NRT level 2 soil moisture product based on Neural Networks, which will be available by autumn 2015. This paper will focus on presenting the

  2. Soil and plant responses from land application of saline-sodic waters: Implications of management

    Energy Technology Data Exchange (ETDEWEB)

    Vance, G.F.; King, L.A.; Ganjegunte, G.K. [University of Wyoming, Laramie, WY (United States). Department for Renewable Resources

    2008-09-15

    Land application of co-produced waters from coalbed natural gas (CBNG) wells is one management option used in the Powder River Basin (PRB) of Wyoming and Montana. Unfortunately the co-produced CBNG waters may be saline and/or sodic. The objective of this study was to examine the effects of irrigation with CBNG waters on soils and plants in the PRB. Soil properties and vegetation responses resulting from 1 to 4 yr of saline sodic water (electrical conductivity (EC) 1.6-4.8 dS m{sup -1} sodium adsorption ratio (SAR), 17-57 mmol L- applications were studied during 2003 and 2004 field seasons on sites (Ustic Torriorthent Haplocambid, Haplargid and Paleargid) representing native range grasslands seeded grass hayfields and alfalfa hayfields. Parameters measured from each irrigated site were compared directly with representative non-irrigated sites. Soil chemical and physical parameters including pH, EC, SAR, exchangeable sodium percent, texture, bulk density, infiltration and Darcy flux rates, were measured at various depth intervals to 120 cm. Mulitple-year applications of saline sodic water produced consistent trends of increased soil EC AND SAR values to depths of 30 cm reduced surface infiltration rates and lowered Darcy flux rates to 120 cm. Significant differences (p {le} 0.05) were determined between irrigated and non-irrigated areas for EC, SAR infiltration rates and Darcy flux (p {le} 0.10) at most sites. Saline sodic CBNG water applications significantly increased native perennial grass biomass production and cover on irrigated as compared with non-irrigated sites; however overall species evenness decreased. Biological effects were variable and complex reflecting site-specific conditions and water and soil management strategies.

  3. Dynamics of {sup 14}C-labeled glucose and ammonium in saline arable soils

    Energy Technology Data Exchange (ETDEWEB)

    Vuelvas-Solorzano, Alma; Hernandez-Matehuala, Rosalina [Instituto Tecnologico de Celaya, Celaya Gto. (Mexico). Dept. de Ing. Bioquimica. Lab. de Bioingenieria; Conde-Barajas, Eloy; Cardenas-Manriquez, Marcela [Instituto Tecnologico de Celaya, Celaya Gto. (Mexico). Dept. de Ing. Ambiental. Lab. de Bioingenieria], e-mail: marcela@itc.mx; Luna-Guido, Marco L.; Dendooven, Luc [Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (Cinvestav), D.F. (Mexico). Dept. de Biotecnologia y Bioingenieria. Lab. de Ecologia de Suelos], e-mail: dendoove@cinvestav.mx

    2009-07-15

    Organic matter dynamics and nutrient availability in saline agricultural soils of the State of Guanajuato might provide information for remediation strategies. {sup 14}C labeled glucose with or without 200 mg kg{sup -}1 of NH{sub 4} {sup +}-N soil was added to two clayey agricultural soils with different electrolytic conductivity (EC), i.e. 0.94 dS m{sup -}1 (low EC; LEC) and 6.72 dS m{sup -}1 (high EC; HEC), to investigate the effect of N availability and salt content on organic material decomposition. Inorganic N dynamics and production of CO{sub 2} and {sup 14}CO{sub 2} were monitored. Approximately 60 % of the glucose-{sup 14}C added to LEC soil evolved as {sup 14}CO{sub 2}, but only 20 % in HEC soil after the incubation period of 21 days. After one day, < 200 mg {sup 14}C was extractable from LEC soil, but > 500 mg {sup 14}C from HEC soil. No N mineralization occurred in the LEC and HEC soils and glucose addition reduced the concentrations of inorganic N in unamended soil and soil amended with NH{sub 4}{sup +}-N. The NO{sub 2}{sup -} and NO{sub 3}{sup -} concentrations were on average higher in LEC than in HEC soil, with exception of NO{sub 2}{sup -} in HEC amended with NH{sub 4}{sup +}-N. It was concluded that increases in soil EC reduced mineralization of the easily decomposable C substrate and resulted in N-depleted soil. (author)

  4. A kinetic approach to evaluate salinity effects on carbon mineralization in a plant residue-amended soil.

    Science.gov (United States)

    Nourbakhsh, Farshid; Sheikh-Hosseini, Ahmad R

    2006-10-01

    The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO(2)-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO(2)-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO(2) evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C (C(0)) was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation.

  5. Toxic effects of heavy metals and their accumulation in vegetables grown in a saline soil.

    Science.gov (United States)

    Li, Qusheng; Cai, Shasha; Mo, Cehui; Chu, Bei; Peng, Lihua; Yang, Fangbing

    2010-01-01

    A pot experiment was carried out to evaluate the effects of heavy metals on biomass, chlorophyll, and antioxidative enzyme activities of eight vegetables grown in a saline soil. The heavy metal accumulation in vegetables was also investigated. Results show that biomass and chlorophyll content of crops decreased with the increase of heavy metal concentration while peroxidase activity increased at low concentration and decreased at high concentration. The total translocation factor values in the eight vegetables are in order: water spinach>Chinese kale>pakchoi>edible amaranth>leaf mustard>Chinese flowering cabbage>green capsicum>tomato. Tomato, which is the most salt tolerant crop of the eight vegetables, also is the most heavy metals resistant studied in terms of growth, peroxidase activity and heavy metals translocation. Salt tolerant fruit vegetables such as tomato might be potential crops for the safe use of saline soils polluted with heavy metals.

  6. [Soil sandy desertification and salinization and their interrelationships in Yanghuang irrigated area of Hongsipu, Ningxia of northwest China].

    Science.gov (United States)

    Yang, Xin-guo; Song, Nai-ping

    2011-09-01

    By the methods of controlled and typical sampling, this paper analyzed the texture, salinization characteristics, cation exchange capacity (CEC), and their correlations in the 0-40 cm soil profiles of corn land, medlar land, and non-utilized land in Yanghuang irrigated area of Hongsipu, Northwest China. Under controlled sampling, the salt content in the soil profiles was 0.69-1.30 g x kg(-1) (except in non-utilized land where the 0-10 cm soil salt content was up to 1.74 g x kg(-1)), with no obvious salinization. The sodium adsorption ratio and exchangeable sodium percentage in the 20-40 cm soil layer of medlar land were 12.18 and 14.1%, respectively, and the total content of clay and silt in the 0-40 cm soil profile of medlar land was up to 37.3% whereas that in the 0-20 cm soil layer of corn land was only 13.5%. In the 20-40 cm soil layer of corn land, the indices of sandy desertification and salinization had significant correlations under controlled sampling but no correlations under typical sampling, while the CEC and the sandy desertification and salinization indices had significant correlations under typical sampling. In different land use types in the study area, soil sandy desertification and salinization had complicated interrelationships, and CEC could be used as the indicator for the changes in soil environmental quality.

  7. Effects of poly-γ-glutamic acid biopreparation (PGAB) on nitrogen conservation in the coastal saline soil

    Science.gov (United States)

    Chen, Lihua; Xu, Xianghong; Zhang, Huan; Han, Rui; Cheng, Yao; Tan, Xueyi; Chen, Xuanyu

    2017-04-01

    Water leaching is the major method to decrease soil salinity of the coastal saline soil. Conservation of soil nutrition in the soil ameliorating process is helpful to maintain soil fertility and prevent environment pollution. In the experiment, glutamic acid and poly-γ-glutamic acid (PGA) producing bacteria were isolated for manufacturing the PGA biopreparation (PGAB), and the effect of PGAB on the soil nitrogen (N) conservation was assayed. The glutamic acid and PGA producing bacteria were identified as Brevibacterium flavum and Bacillus amyloliquefaciens. After soil leached with water for 90 days, compared to control treatment, salt concentration of 0-30cm soil with PGAB treatment was lowered by 39.93%, however the total N loss was decreased by 65.37%. Compared to control, the microbial biomass N increased by 1.19 times at 0-30 cm soil with PGAB treatment. The populations of soil total bacteria, fungi, actinomyces, nitrogen fixing bacteria, ammonifying bacteria, nitrifying bacteria and denitrifying bacteria and biomass of soil algae were significantly increased in PGAB treatment, while anaerobic bacteria decreased (P 0.25 mm and 0.02 mm resistance coefficient of PGAB treatment increased by 50%. All these suggested that the PGAB conserved the soil nitrogen effectively in the process of soil water leaching and improved the coastal saline soil quality.

  8. Assessment of some soil properties by spatial variability in saline and sodic soils in Arsanjan plain, Southern Iran.

    Science.gov (United States)

    Emadi, Mostafa; Baghernejad, Majid; Emadi, Mehdi; Maftoun, Manouchehr

    2008-01-15

    Spatial patterns for several soil parameters such soil texture, Exchangeable Sodium Percentage (ESP), Electrical Conductivity (ECe), soil pH, Cation Exchange Capacity (CEC) were examined in saline and sodic soils in Arsanjan plain, Southern Iran, in order to identify their spatial distribution for implementation of a site-specific management. Soil samples were collected from 0-30, 30-60 and 60-90 cm soil depths at 85 sampling sites. Data were analyzed both statistically and geostatistically on the basis of the semivariogram. The spatial distribution model and spatial dependence level varied between soil parameters. Soil pH and ESP had the minimum and maximum variability at all depths, respectively. Soil properties indicated moderate to strong spatial dependence. ECe exhibited moderate spatial dependence at three depths; pH and ESP had a moderate spatial dependence at 0-30 cm and strong spatial dependence at 30-60 and 60-90 cm depths. Clay and CEC exhibited strong spatial dependence for the 0-30 cm and weak spatial dependence at 30-60 and 60-90 cm depths. Sand and silt had a non-spatial dependence at 0-30 cm and weak spatial dependency at 30-60 and 60-90 cm depths. The spatial variability in small distances of ECe, CEC, pH and ESP generally increased with depth. All geostatistical range values were greater than 1168 m. The results reported herein indicated that the strong spatial dependency of soil properties would lead to the extrinsic factors such as ground water level and drainage. It is important to know the spatial dependence of soil parameters, as management parameters with strong spatial dependence will be more readily managed and an accurate site-specific scheme for precision farming more easily developed.

  9. Modeling the effects of different irrigation water salinity on soil water movement, uptake and multicomponent solute transport

    Science.gov (United States)

    Lekakis, E. H.; Antonopoulos, V. Z.

    2015-11-01

    Simulation models can be important tools for analyzing and managing irrigation, soil salinization or crop production problems. In this study a mathematical model that describes the water movement and mass transport of individual ions (Ca2+, Mg2+ and Na+) and overall soil salinity by means of the soil solution electrical conductivity, is used. The mass transport equations of Ca2+, Mg2+ and Na+ have been incorporated as part of the integrated model WANISIM and the soil salinity was computed as the sum of individual ions. The model was calibrated and validated against field data, collected during a three year experiment in plots of maize, irrigated with three different irrigation water qualities, at Thessaloniki area in Northern Greece. The model was also used to evaluate salinization and sodification hazards by the use of irrigation water with increasing electrical conductivity of 0.8, 3.2 and 6.4 dS m-1, while maintaining a ratio of Ca2+:Mg2+:Na+ equal to 3:3:2. The qualitative and quantitative procedures for results evaluation showed that there was good agreement between the simulated and measured values of the water content, overall salinity and the concentration of individual soluble cations, at two soil layers (0-35 and 35-75 cm). Nutrient uptake was also taken into account. Locally available irrigation water (ECiw = 0.8 dS m-1) did not cause soil salinization or sodification. On the other hand, irrigation water with ECiw equal to 3.2 and 6.4 dS m-1 caused severe soil salinization, but not sodification. The rainfall water during the winter seasons was not sufficient to leach salts below the soil profile of 110 cm. The modified version of model WANISIM is able to predict the effects of irrigation with saline waters on soil and plant growth and it is suitable for irrigation management in areas with scarce and low quality water resources.

  10. Forest Clearcutting and Site Preparation on a Saline Soil in East Texas: Impacts on Water Quality

    Science.gov (United States)

    Matthew McBroom; Mingteh Chang; Alexander K. Sayok

    2002-01-01

    Three 0.02 hectare plot-watersheds were installed on a saline soil in the Davy Crockett National Forest near Apple Springs, Texas. Each plot was installed with an H-flume, FW-1 automatic water level recorder, Coshocton N-1 runoff sampler, and two storage tanks. One watershed was undisturbed forested and served a control, one was clearcut without any site-preparation,...

  11. Quantitative Estimating Salt Content of Saline Soil Using Laboratory Hyperspectral Data Treated by Fractional Derivative

    Directory of Open Access Journals (Sweden)

    Dong Zhang

    2016-01-01

    Full Text Available Most present researches on estimation of soil salinity by hyperspectral data have focused on the spectral reflectance or their integer derivatives but ignored the fractional derivative information of hyperspectral data. Motivated by this situation, the selected study area is the Ebinur Lake basin located in the southwest border in the Xinjiang Uygur Autonomous Region, China, with severe salinization. The field work was conducted from 15 to 25 October, 2014, and a total of 180 soil samples were collected from 45 sampling sites; after measuring the soil salt content and spectral reflectance in the laboratory, the range from 0 to 2 was divided into 11 orders (interval 0.2 and then the hyperspectral data were treated by 4 kinds of mathematical transformations and 11 orders of fractional derivatives. Combined with the soil salt content, partial least square regression method was applied for model calibrations and predictions and some indexes were used to evaluate the performance of models. The results showed that the retrieval model built up by 250 bands based on 1.2-order derivative of 1/lg⁡R had excellent capacity of estimating soil salt content in the study area (RMSEC=14.685 g/kg, RMSEP=14.713 g/kg, R2C=0.782, R2P=0.768, and RPD = 2.080. This study provides an application reference for quantitative estimations of other land surface parameters and some other applications on hyperspectral technology.

  12. Effects of Soil Salinization and Waterlogging on the Concentrations of Some Macronutrients and Sodium in Corn Root

    Directory of Open Access Journals (Sweden)

    N Najafi

    2015-05-01

    Full Text Available Salinity and waterlogging are two abiotic stresses decrease plants yield. In this research, the effects of soil salinization and waterlogging having concentrations of calcium (Ca, potassium (K, magnesium (Mg and sodium (Na and K:Na ratio in corn (Zea mays cv. single cross 704 root were studied under greenhouse conditions. A factorial experiment with two factors on the basis of completely randomized design with three replications was performed. The factors under study were: waterlogging duration in five levels (0, 2, 4, 8, 20 days and soil saturate extract salinity in four levels (0.11, 2, 4, 8 dS/m. A loamy sand soil for plant growth substrate and NaCl salt for establishing the levels of salinity was used. The salinity and waterlogging factors were imposed simultaneously to the plants from the five-leaf stage of plant growth period. The plants were harvested 60 days after sowing and the concentrations of Ca, K, Mg and Na in corn root were determined by dry ashi method. The results showed that by increasing the level of NaCl salinity in the soil, the K concentration and K:Na ratio of corn root were decreased significantly but concentrations of Ca, Mg and Na in corn root were increased significantly. The Mg and Na concentrations of root in waterlogged conditions were significantly lower than that of non-waterlogged conditions but the K and Ca concentrations of root in waterlogged conditions were significantly greater than non-waterlogged conditions. However, the effects of soil waterlogging duration on the Ca, K, Mg and Na concentrations and Na:K ratio of root were dependent on the level of NaCl salinity in the soil. The results demonstrated that even short periods of soil waterlogging had considerable long-term effects on the concentrations of Ca, K, Mg and Na and K:Na ratio in corn root under saline and non-saline conditions.

  13. Halophytes as components of lawns under different soil salinity and human impact in the health resort "Ciechocinek"

    National Research Council Canada - National Science Library

    Andrzej Nienartowicz; Agnieszka Piernik; Joanna Marcykiewicz; Marta Lis; Mieczyslaw Kunz; Silvio Viglia

    2010-01-01

    .... It was found that a different level of saline water inflow into the soil and a different use of these lawns are the main causes of the observed differences in the number and the species composition...

  14. Halophytes as components of lawns under different soil salinity and human impact in the health resort “Ciechocinek”

    National Research Council Canada - National Science Library

    Andrzej Nienartowicz; Agnieszka Piernik; Joanna Marcykiewicz; Marta Lis; Mieczysław Kunz; Silvio Viglia

    2010-01-01

    .... It was found that a different level of saline water inflow into the soil and a different use of these lawns are the main causes of the observed differences in the number and the species composition...

  15. [Dynamics of seasonal plant growth in halophytic meadows taking into account the temperature factor and soil salinity level].

    Science.gov (United States)

    Pis'man, T I; Slosar', N A

    2012-01-01

    A mathematical model has been constructed to describe the growth dynamics of various plant communities of halophytic meadows depending on the temperature factor and degree of soil salinity. Field investigation of the yields of halophytic meadow plant communities were performed in the coastal area of Kurinka Lake in the Altaiskii district of the Republic of Khakasia in 2004 and 2006. The results of field investigations and model studies show that there is a correlation between plant growth and air temperature for plant communities growing on soils with the lowest and medium salinity levels. It was proven in model studies that for the plant communities that grow on highly saline (3.58%) soils, not only air temperature but also the salinity level of the soil should be taken into account.

  16. Proposal - Impacts of a changing climate: monitoring the long term persistence and migration of soil salinities in Bayou Sauvage NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Proposal involves the long-term assessment of soil salinity at Bayou Sauvage NWR resulting from the Rapid ecosystem changes resulting from Hurricane Katrina in 2005...

  17. Soil and plant responses from land application of saline-sodic waters: implications of management.

    Science.gov (United States)

    Vance, George F; King, Lyle A; Ganjegunte, Girisha K

    2008-01-01

    Land application of co-produced waters from coalbed natural gas (CBNG) wells is one management option used in the Powder River Basin (PRB) of Wyoming and Montana. Unfortunately, the co-produced CBNG waters may be saline and/or sodic. The objective of this study was to examine the effects of irrigation with CBNG waters on soils and plants in the PRB. Soil properties and vegetation responses resulting from 1 to 4 yr of saline-sodic water (electrical conductivity [EC], 1.6-4.8 dS m(-1); sodium adsorption ratio [SAR], 17-57 mmol(1/2) L(-1/2)) applications were studied during 2003 and 2004 field seasons on sites (Ustic Torriorthent, Haplocambid, Haplargid, and Paleargid) representing native range grasslands, seeded grass hayfields, and alfalfa hayfields. Parameters measured from each irrigated site were compared directly with representative non-irrigated sites. Soil chemical and physical parameters, including pH, EC, SAR, exchangeable sodium percent, texture, bulk density, infiltration, and Darcy flux rates, were measured at various depth intervals to 120 cm. Multiple-year applications of saline-sodic water produced consistent trends of increased soil EC and SAR values to depths of 30 cm, reduced surface infiltration rates, and lowered Darcy flux rates to 120 cm. Significant differences (p sodic CBNG water applications significantly increased native perennial grass biomass production and cover on irrigated as compared with non-irrigated sites; however, overall species evenness decreased. Biological effects were variable and complex, reflecting site-specific conditions and water and soil management strategies.

  18. Effects of deficit drip-irrigation scheduling regimes with saline water on pepper yield, water productivity and soil salinity under arid conditions of Tunisia

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2012-12-01

    Full Text Available A two-year study was carried out in order to assess the effects of different irrigation scheduling regimes with saline water on soil salinity, yield and water productivity of pepper under actual commercial-farming conditions in the arid region of Tunisia. Pepper was grown on a sandy soil and drip-irrigated with water having an ECi of 3.6 dS/m. Irrigation treatments consisted in water replacements of accumulated ETc at levels of 100% (FI, full irrigation, 80% (DI-80, 60% (DI-60, when the readily available water in the control treatment (FI is depleted, deficit irrigation during ripening stage (FI-MDI60 and farmer method corresponding to irrigation practices implemented by the local farmers (FM. Results on pepper yield and soil salinity are globally consistent between the two-year experiments and shows significant difference between irrigation regimes. Higher soil salinity was maintained over the two seasons, 2008 and 2009, with DI-60 and FM treatments than FI. FI-MDI60 and DI-80 treatments resulted also in low ECe values. Highest yields for both years were obtained under FI (22.3 and 24.4 t/ha although we didn’t find significant differences with the regulated deficit irrigation treatment (FI-DI60. However, the DI-80 and DI-60 treatments caused significant reductions in pepper yields through a reduction in fruits number/m² and average fruit weight in comparison with FI treatment. The FM increased soil salinity and caused significant reductions in yield with 14 to 43%, 12 to 39% more irrigation water use than FI, FI-MDI60 and DI-80 treatments, respectively, in 2008 and 2009. Yields for all irrigation treatments were higher in the second year compared to the first year. Water productivity (WP values reflected this difference and varied between 2.31 and 5.49 kg/m3. The WP was found to vary significantly among treatments, where the highest and the lowest values were observed for DI-60 treatment and FM, respectively. FI treatment provides

  19. Digital Mapping of Soil Salinity and Crop Yield across a Coastal Agricultural Landscape Using Repeated Electromagnetic Induction (EMI Surveys.

    Directory of Open Access Journals (Sweden)

    Rongjiang Yao

    Full Text Available Reliable and real-time information on soil and crop properties is important for the development of management practices in accordance with the requirements of a specific soil and crop within individual field units. This is particularly the case in salt-affected agricultural landscape where managing the spatial variability of soil salinity is essential to minimize salinization and maximize crop output. The primary objectives were to use linear mixed-effects model for soil salinity and crop yield calibration with horizontal and vertical electromagnetic induction (EMI measurements as ancillary data, to characterize the spatial distribution of soil salinity and crop yield and to verify the accuracy of spatial estimation. Horizontal and vertical EMI (type EM38 measurements at 252 locations were made during each survey, and root zone soil samples and crop samples at 64 sampling sites were collected. This work was periodically conducted on eight dates from June 2012 to May 2013 in a coastal salt-affected mud farmland. Multiple linear regression (MLR and restricted maximum likelihood (REML were applied to calibrate root zone soil salinity (ECe and crop annual output (CAO using ancillary data, and spatial distribution of soil ECe and CAO was generated using digital soil mapping (DSM and the precision of spatial estimation was examined using the collected meteorological and groundwater data. Results indicated that a reduced model with EMh as a predictor was satisfactory for root zone ECe calibration, whereas a full model with both EMh and EMv as predictors met the requirement of CAO calibration. The obtained distribution maps of ECe showed consistency with those of EMI measurements at the corresponding time, and the spatial distribution of CAO generated from ancillary data showed agreement with that derived from raw crop data. Statistics of jackknifing procedure confirmed that the spatial estimation of ECe and CAO exhibited reliability and high accuracy

  20. Arbuscular mycorrhizal fungi and plant symbiosis in a saline-sodic soil.

    Science.gov (United States)

    García, Ileana V; Mendoza, Rodolfo E

    2007-05-01

    The seasonality of arbuscular mycorrhizal (AM) fungi-plant symbiosis in Lotus glaber Mill. and Stenotaphrum secundatum (Walt.) O.K. and the association with phosphorus (P) plant nutrition were studied in a saline-sodic soil at the four seasons during a year. Plant roots of both species were densely colonized by AM fungi (90 and 73%, respectively in L. glaber and S. secundatum) at high values of soil pH (9.2) and exchangeable sodium percentage (65%). The percentage of colonized root length differed between species and showed seasonality. The morphology of root colonization had a similar pattern in both species. The arbuscular colonization fraction increased at the beginning of the growing season and was positively associated with increased P concentration in both shoot and root tissue. The vesicular colonization fraction was high in summer when plants suffer from stress imposed by high temperatures and drought periods, and negatively associated with P in plant tissue. Spore and hyphal densities in soil were not associated with AM root colonization and did not show seasonality. Our results suggest that AM fungi can survive and colonize L. glaber and S. secundatum roots adapted to extreme saline-sodic soil condition. The symbiosis responds to seasonality and P uptake by the host altering the morphology of root colonization.

  1. Growth, water status and nutrient accumulation of seedlings of Cassia fistula L. in response to soil salinity

    OpenAIRE

    Hardikar, Seema Abhay; Pandey, Amar Nath

    2011-01-01

    Greenhouse experiments were conducted to assess the effect of soil salinity on emergence, growth, water status, proline content and mineral accumulation of seedlings of Cassia fistula L. (Fabaceae). NaCl was added to the soil and salinity was maintained at 0.2, 2.1, 3.9, 6.2, 8.1, 10.0 and 11.9 dSm-1. Salinity caused reduction in water content and water potential of tissues that resulted in internal water deficit to plants. Consequently, seedling growth significant...

  2. A kinetic approach to evaluate salinity effects on carbon mineralization in a plant residue-amended soil*

    OpenAIRE

    Nourbakhsh, Farshid; Sheikh-Hosseini, Ahmad R.

    2006-01-01

    The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was use...

  3. Effective bioremediation of a petroleum-polluted saline soil by a surfactant-producing Pseudomonas aeruginosa consortium

    Directory of Open Access Journals (Sweden)

    Ali Ebadi

    2017-11-01

    Full Text Available Bacteria able to produce biosurfactants can use petroleum-based hydrocarbons as a carbon source. Herein, four biosurfactant-producing Pseudomonas aeruginosa strains, isolated from oil-contaminated saline soil, were combined to form a bacterial consortium. The inoculation of the consortium to contaminated soil alleviated the adverse effects of salinity on biodegradation and increased the rate of degradation of petroleum hydrocarbon approximately 30% compared to the rate achieved in non-treated soil. In saline condition, treatment of polluted soil with the consortium led to a significant boost in the activity of dehydrogenase (approximately 2-fold. A lettuce seedling bioassay showed that, following the treatment, the soil's level of phytotoxicity was reduced up to 30% compared to non-treated soil. Treatment with an appropriate bacterial consortium can represent an effective means of reducing the adverse effects of salinity on the microbial degradation of petroleum and thus provides enhancement in the efficiency of microbial remediation of oil-contaminated saline soils.

  4. Desodification from calcareous saline sodic soil through phytoremediation with Phragmites australis (Cav.) Trin. ex Steud. and gypsum.

    Science.gov (United States)

    Abro, Saeed Akhter; Otho, Aijaz Ali; Bughio, Farooque A; Sahito, Oan Mohammad; Jamali, Abdul Rauf; Mahar, Amanullah

    2017-05-22

    The reclamation of saline sodic soils requires sodium removal and the phytoremediation is one of the proven low-cost, low-risk technologies for reclaiming such soils. However, the role of P. australis in reclaiming saline sodic soil has not been evaluated extensively. The comparative reclaiming role of P. australis and gypsum was evaluated in a column experiment on a sandy clay saline sodic soil with ECe 74.7 dS m(-1), SAR 63.2, Na(+) 361 g kg(-1) and pH 8.46. The gypsum at 100% soil requirement, planting common reed (P. australis) alone, P. australis + gypsum at 50% soil gypsum requirements and leaching (control without plant and gypsum) were four treatments applied. After 11 weeks of incubation, the results showed that all treatments including control significantly reduced pH, EC, exchangeable Na(+) and SAR from the initial values but the control being with least results. The gypsum and P. australis + gypsum were highly effective in salinity (ECe) reduction while, sodicity (SAR) and Na(+) reductions were significantly higher in P. australis + gypsum treatment. The reclamation efficiency in terms of Na(+) (83.4%) and SAR (86.8%) reduction was highest in P. australis + gypsum. It is concluded that phytoremediation is an effective tool to reclaim saline sodic soil.

  5. Salinity altered root distribution and increased diversity of bacterial communities in the rhizosphere soil of Jerusalem artichoke

    Science.gov (United States)

    Yang, Hui; Hu, Jinxiang; Long, Xiaohua; Liu, Zhaopu; Rengel, Zed

    2016-02-01

    The interaction between roots and bacterial communities in halophytic species is poorly understood. Here, we used Jerusalem artichoke cultivar Nanyu 1 (NY-1) to characterise root distribution patterns and determine diversity and abundance of bacteria in the rhizosphere soil under variable salinity. Root growth was not inhibited within the salinity range 1.2 to 1.9 g salt/kg, but roots were mainly confined to 0-20 cm soil layer vertically and 0-30 cm horizontally from the plant centre. Root concentrations of K+, Na+, Mg2+ and particularly Ca2+ were relatively high under salinity stress. High salinity stress decreased soil invertase and catalase activity. Using a next-generation, Illumina-based sequencing approach, we determined higher diversity of bacteria in the rhizosphere soil at high than low salinity. More than 15,500 valid reads were obtained, and Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria predominated in all samples, accounting for >80% of the reads. On a genus level, 636 genera were common to the low and high salinity treatments at 0-5 cm and 5-10 cm depth. The abundance of Steroidobacter and Sphingomonas was significantly decreased by increasing salinity. Higher Shannon and Chao 1 indices with increasing severity of salt stress indicated that high salt stress increased diversity in the bacterial communities.

  6. Effect of organic materials on the chemical properties of saline soil in the Yellow River Delta of China

    Science.gov (United States)

    Yu, Yan; Liu, Jie; Liu, Chunmeng; Zong, Shuang; Lu, Zhaohua

    2015-06-01

    A 180-day incubation experiment was conducted to investigate the effect of different organic materials on the chemical properties of coastal soil with high salinity and relatively low pH. Four organic materials (three kinds of plant residues: straw, composted straw, and fresh reed; and one kind of poultry manure: chicken manure) were applied at a ratio of 15 g·kg-1 to samples of costal saline soil from the Yellow River Delta of China. The results showed that the soil pH and exchangeable sodium percentage (ESP) decreased, whereas soil cation exchangeable capacity (CEC) and macronutrient concentrations increased, regardless of the type of organic material used. All treatments showed a remarkable increase in soil soluble organic carbon (SOC) during the 180-day incubation. The peak values of SOC in descending order were chicken manure, reed, composted straw, straw, and control soil. At the end of incubation, the highest level of SOC occurred in the straw-amended soil, followed by composted straw, reed, and chicken manureamended soils. Soil respiration rate and available nitrogen were significantly influenced by the type of material used. Although reed-amended soil had a relatively high SOC and respiration rate, the ESP was reduced the least. Considering the possible risk of heavy metals caused by chicken manure, it is proposed that straw and composted straw are the more efficient materials to use for reclaiming costal saline soil and improving the availability of macronutrients.

  7. Saline soil properties, quality and productivity of wheat grown with bagasse ash and thiourea in different climatic zones.

    Science.gov (United States)

    Seleiman, Mahmoud F; Kheir, Ahmed M S

    2018-02-01

    Soil salinity and atmosphere temperature change have negative impacts on crop productivity and its quality and can pose a significant risk to soil properties in semi-arid regions. We conducted two field experiments in North (first zone) and South (second zone) of Egypt to investigate the effects of soil bagasse ash (10 ton ha -1 ), foliar thiourea (240 g ha -1 ) and their combination in comparison to the control treatment on saline soil properties and productivity and quality traits of wheat. All studied treatments were received the recommended rate of N, P and K fertilizations. Combination of soil bagasse ash and foliar thiourea application resulted in a significant improvement of most studied soil properties (i.e. EC, compaction, hydraulic conductivity, OM and available P, K, N contents) after harvest in comparison to other treatments in both of zones. Also, it enhanced growth and grain yield of wheat in terms of photosynthesis related attributes and yield components. Moreover, combination of soil bagasse ash and foliar thiourea application resulted in superior grain quality traits in terms of carbohydrate, fibre, protein and ash contents than separated application of soil bagasse ash, foliar thiourea or even control treatment. In conclusion, combination of soil bagasse ash and foliar thiourea application can be used as suitable option to enhance plant nutrition, wheat productivity and improve wheat grain quality and soil traits in saline soil as well as can alleviate heat stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Soil salinity and matric potential interaction on water use, water use efficiency and yield response factor of bean and wheat.

    Science.gov (United States)

    Khataar, Mahnaz; Mohhamadi, Mohammad Hossien; Shabani, Farzin

    2018-02-08

    We studied the effects of soil matric potential and salinity on the water use (WU), water use efficiency (WUE) and yield response factor (Ky), for wheat (Triticum aestivum cv. Mahdavi) and bean (Phaseoulus vulgaris cv. COS16) in sandy loam and clay loam soils under greenhouse conditions. Results showed that aeration porosity is the predominant factor controlling WU, WUE, Ky and shoot biomass (Bs) at high soil water potentials. As matric potential was decreased, soil aeration improved, with Bs, WU and Ky reaching maximum value at -6 to -10 kPa, under all salinities. Wheat WUE remained almost unchanged by reduction of matric potential under low salinities (EC ≤ 8 dSm-1), but increased under higher salinities (EC ≥ 8 dSm-1), as did bean WUE at all salinities, as matric potential decreased to -33 kPa. Wheat WUE exceeds that of bean in both sandy loam and clay loam soils. WUE of both plants increased with higher shoot/root ratio and a high correlation coefficient exists between them. Results showed that salinity decreases all parameters, particularly at high potentials (h = -2 kPa), and amplifies the effects of waterlogging. Further, we observed a strong relationship between transpiration (T) and root respiration (Rr) for all experiments.

  9. Morphological and structural plasticity of grassland species in response to a gradient in saline-sodic soils.

    Science.gov (United States)

    Huang, Y; Song, Y; Li, G; Drake, P L; Zheng, W; Li, Z; Zhou, D

    2015-11-01

    The abundance and distribution of species can be ascribed to both environmental heterogeneity and stress tolerance, with the latter measure sometimes associated with phenotypic plasticity. Although phenotypic plasticity varies predictably in response to common forms of stress, we lack a mechanistic understanding of the response of species to high saline-sodic soils. We compared the phenotypic plasticity of three pairs of high and low saline-sodic tolerant congeners from the families Poaceae (Leymus chinensis versus L. secalinus), Fabaceae (Lespedeza davurica versus L. bicolor) and Asteraceae (Artemisia mongolica versus A. sieversiana) in a controlled pot experiment in the Songnen grassland, China. The low tolerant species, L. secalinus and A. sieversiana exhibited higher plasticity in response to soil salinity and sodicity than their paired congeners. Highly tolerant species, L. chinensis and A. mongolica, had higher values for several important morphological traits, such as shoot length and total biomass under the high saline-sodic soil treatment than their paired congeners. In contrast, congeners from the family Fabaceae, L. davurica and L. bicolor, did not exhibit significantly different plasticity in response to soil salinity and sodicity. All species held a constant reproductive effort in response to saline-sodic soil stress. The different responses between low and high tolerant species offer an explanation for the distribution patterns of these species in the Songnen grassland. Highly tolerant species showed less morphological plasticity over a range of saline-sodic conditions than their paired congeners, which may manifest as an inability to compete with co-occurring species in locations where saline-sodic soils are absent. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. Estimation of soil salinity in a drip irrigation system by using joint inversion of multicoil electromagnetic induction measurements

    KAUST Repository

    Jadoon, Khan Zaib

    2015-05-12

    Low frequency electromagnetic induction (EMI) is becoming a useful tool for soil characterization due to its fast measurement capability and sensitivity to soil moisture and salinity. In this research, a new EMI system (the CMD mini-Explorer) is used for subsurface characterization of soil salinity in a drip irrigation system via a joint inversion approach of multiconfiguration EMI measurements. EMI measurements were conducted across a farm where Acacia trees are irrigated with brackish water. In situ measurements of vertical bulk electrical conductivity (σb) were recorded in different pits along one of the transects to calibrate the EMI measurements and to compare with the modeled electrical conductivity (σ) obtained by the joint inversion of multiconfiguration EMI measurements. Estimates of σ were then converted into the universal standard of soil salinity measurement (i.e., electrical conductivity of a saturated soil paste extract – ECe). Soil apparent electrical conductivity (ECa) was repeatedly measured with the CMD mini-Explorer to investigate the temperature stability of the new system at a fixed location, where the ambient air temperature increased from 26°C to 46°C. Results indicate that the new EMI system is very stable in high temperature environments, especially above 40°C, where most other approaches give unstable measurements. In addition, the distribution pattern of soil salinity is well estimated quantitatively by the joint inversion of multicomponent EMI measurements. The approach of joint inversion of EMI measurements allows for the quantitative mapping of the soil salinity distribution pattern and can be utilized for the management of soil salinity.

  11. Soil salinity and acidity : spatial variabil[it]y and effects on rice production in West Africa's mangrove zone

    NARCIS (Netherlands)

    Sylla, M.

    1994-01-01

    In the mangrove environment of West Africa, high spatial and temporal variability of soil constraints (salinity and acidity) to rice production is a problem for the transfer and adoption of new agronomic techniques, for land use planning, and for soil and water management. Recently, several

  12. Simultaneous monitoring of soil water content and salinity with a low-cost capacitance-resistance probe.

    Science.gov (United States)

    Scudiero, Elia; Berti, Antonio; Teatini, Pietro; Morari, Francesco

    2012-12-18

    Capacitance and resistivity sensors can be used to continuously monitor soil volumetric water content (θ) and pore-water electrical conductivity (EC(p)) with non-destructive methods. However, dielectric readings of capacitance sensors operating at low frequencies are normally biased by high soil electrical conductivity. A procedure to calibrate capacitance-resistance probes in saline conditions was implemented in contrasting soils. A low-cost capacitance-resistance probe (ECH2O-5TE, 70 MHz, Decagon Devices, Pullman, WA, USA) was used in five soils at four water contents (i.e., from dry conditions to saturation) and four salinity levels of the wetting solution (0, 5, 10, and 15 dS · m-1). θ was accurately predicted as a function of the dielectric constant, apparent electrical conductivity (EC(a)), texture and organic carbon content, even in high salinity conditions. Four models to estimate pore-water electrical conductivity were tested and a set of empirical predicting functions were identified to estimate the model parameters based on easily available soil properties (e.g., texture, soil organic matter). The four models were reformulated to estimate EC(p) as a function of EC(a), dielectric readings, and soil characteristics, improving their performances with respect to the original model formulation. Low-cost capacitance-resistance probes, if properly calibrated, can be effectively used to monitor water and solute dynamics in saline soils.

  13. Soil salinity mapping and hydrological drought indices assessment in arid environments based on remote sensing techniques

    Science.gov (United States)

    Elhag, Mohamed; Bahrawi, Jarbou A.

    2017-03-01

    Vegetation indices are mostly described as crop water derivatives. The normalized difference vegetation index (NDVI) is one of the oldest remote sensing applications that is widely used to evaluate crop vigor directly and crop water relationships indirectly. Recently, several NDVI derivatives were exclusively used to assess crop water relationships. Four hydrological drought indices are examined in the current research study. The water supply vegetation index (WSVI), the soil-adjusted vegetation index (SAVI), the moisture stress index (MSI) and the normalized difference infrared index (NDII) are implemented in the current study as an indirect tool to map the effect of different soil salinity levels on crop water stress in arid environments. In arid environments, such as Saudi Arabia, water resources are under pressure, especially groundwater levels. Groundwater wells are rapidly depleted due to the heavy abstraction of the reserved water. Heavy abstractions of groundwater, which exceed crop water requirements in most of the cases, are powered by high evaporation rates in the designated study area because of the long days of extremely hot summer. Landsat 8 OLI data were extensively used in the current research to obtain several vegetation indices in response to soil salinity in Wadi ad-Dawasir. Principal component analyses (PCA) and artificial neural network (ANN) analyses are complementary tools used to understand the regression pattern of the hydrological drought indices in the designated study area.

  14. Microstrip Antenna for Remote Sensing of Soil Moisture and Sea Surface Salinity

    Science.gov (United States)

    Ramhat-Samii, Yahya; Kona, Keerti; Manteghi, Majid; Dinardo, Steven; Hunter, Don; Njoku, Eni; Wilson, Wiliam; Yueh, Simon

    2009-01-01

    This compact, lightweight, dual-frequency antenna feed developed for future soil moisture and sea surface salinity (SSS) missions can benefit future soil and ocean studies by lowering mass, volume, and cost of the antenna system. It also allows for airborne soil moisture and salinity remote sensors operating on small aircraft. While microstrip antenna technology has been developed for radio communications, it has yet to be applied to combined radar and radiometer for Earth remote sensing. The antenna feed provides a key instrument element enabling high-resolution radiometric observations with large, deployable antennas. The design is based on the microstrip stacked-patch array (MSPA) used to feed a large, lightweight, deployable, rotating mesh antenna for spaceborne L-band (approximately equal to 1 GHz) passive and active sensing systems. The array consists of stacked patches to provide dual-frequency capability and suitable radiation patterns. The stacked-patch microstrip element was designed to cover the required L-band center frequencies at 1.26 GHz (lower patch) and 1.413 GHz (upper patch), with dual-linear polarization capabilities. The dimension of patches produces the required frequencies. To achieve excellent polarization isolation and control of antenna sidelobes for the MSPA, the orientation of each stacked-patch element within the array is optimized to reduce the cross-polarization. A specialized feed-distribution network was designed to achieve the required excitation amplitude and phase for each stacked-patch element.

  15. Neotyphodium coenophialum-infected tall fescue and its potential application in the phytoremediation of saline soils.

    Science.gov (United States)

    Yin, L; Ren, A; Wei, M; Wu, L; Zhou, Y; Li, X; Gao, Y

    2014-01-01

    The growth response of endophyte-infected (EI) and endophyte-free (EF) tall fescue to salt stress was investigated under two growing systems (hydroponic and soil in pots). The hydroponic experiment showed that endophyte infection significantly increased tiller and leaf number, which led to an increase in the total biomass of the host grass. Endophyte infection enhanced Na accumulation in the host grass and improved Na transport from the roots to the shoots. With a 15 g l(-1) NaCl treatment, the phytoextraction efficiency of EI tall fescue was 2.34-fold higher than EF plants. When the plants were grown in saline soils, endophyte infection also significantly increased tiller number, shoot height and the total biomass of the host grass. Although EI tall fescue cannot accumulate Na to a level high enough for it to be termed a halophyte, the increased biomass production and stress tolerance suggested that endophyte/plant associations had the potential to be a model for endophyte-assisted phytoextraction in saline soils.

  16. EFFECT OF SOIL SULFUR FERTILIZER AND SOME FOLIAR FERTILIZERS ON GROWTH AND YIELD OF BROCCOLI IN SALINE SOIL

    Directory of Open Access Journals (Sweden)

    Ali Husain JASIM

    2015-12-01

    Full Text Available Factorial experiment was conducted in the open fields of Agricultural College, Al-Qasim Green University during the agricultural seasons of 2013/2014 and 2014/2015 to study the effect of adding two levels of agricultural sulfur (control and add 100 kg.ha-1 and four levels of nutrient spray (without spray, high-potash fertilizer, high-phosphorus fertilizer and humic acid on growth and yield of broccoli under drip irrigation and polyethylene soil mulching in saline soil (9.6 dS.m-1. Randomized complete block design with three replicates was used. The results showed that agricultural sulfur led to increase number of leaves, leaf area, leaves chlorophyll content, diameter and weight of flower head compared to control. Spraying foliar fertilizer and its interaction with sulfur fertilizer also led to increase all of parameters above (except leaves chlorophyll content significantly compared to control treatment.

  17. Effect of Organic Matter and Gypsum Powder Some Traits of Maize in a Saline-Sodic Soil

    Directory of Open Access Journals (Sweden)

    M Khotabaee

    2015-04-01

    Full Text Available Saline-sodic soils have improper physical, chemical and biological condition and the crop productivity is low in these conditions. Application of conditioners often can be a proper solution for reclamation and improving the productivity of saline-sodic soils. In order to study the effect of some conditioners on soil chemical characteristics and yield of maize (SC260 cultivar in a saline-sodic soil, an experiment was carried out as a completely randomized design with 3 replications in a research greenhouse of Ferdowsi university of Mashhad. The studied treatments included control and 10 ton/ha of compost (MC, vermi-compost (VC, poultry manure (PM, and gypsum powder (G. The results showed that poultry manure and vemi-compost treatments increased significantly (p

  18. Salinity effect of irrigation with treated wastewater in basal soil respiration in SE of Spain

    Science.gov (United States)

    Morugan, A.; Garcia-Orenes, F.; Mataix-Solera, J.

    2012-04-01

    The use of treated wastewater for the irrigation of agricultural soils is an alternative to utilizing better-quality water, especially in semiarid regions where water shortage is a very serious problem. Wastewater use in agriculture is not a new practice, all over the world this reuse has been common practice for a long time, but the concept is of greater importance currently because of the global water crisis. Replacement of freshwater by treated wastewater is seen as an important conservation strategy contributing to agricultural production, substantial benefits can derive from using this nutrient-rich waste water but there can also be a negative impact. For this reason it is necessary to know precisely the composition of water before applying it to the soil in order to guarantee minimal impact in terms of contamination and salinization. In this work we have been studying, for more than three years, different parameters in calcareous soils irrigated with treated wastewater in an agricultural Mediterranean area located at Biar (Alicante, SE Spain), with a crop of grape (Vitis labrusca). Three types of waters were used for the irrigation of the soil: fresh water (control) (TC), and treated wastewater from secondary (T2) and tertiary treatment (T3). Three different doses of irrigation have been applied to fit the efficiency of the irrigation to the crop and soil type during the study period. A soil sampling was carried out every four months. We show the results of the evolution of basal soil respiration (BSR), and its relationship with other parameters. We observed a similar pattern of behavior for BSR between treatments, a decrease at the first eighteen months of irrigation and an increase at the end of study. In our study case, the variations of BSR obtained for all the treatments seem to be closely related to the dose and frequency of irrigation and the related soil wetting and drying cycles. However, the results showed a negative correlation between BSR and

  19. Electrical and seismic response of saline permafrost soil during freeze - Thaw transition

    Science.gov (United States)

    Wu, Yuxin; Nakagawa, Seiji; Kneafsey, Timothy J.; Dafflon, Baptiste; Hubbard, Susan

    2017-11-01

    We conducted laboratory studies on the geophysical signals from Arctic saline permafrost soils to help understand the physical and mechanical processes during freeze-thaw cycles. Our results revealed low electrical resistivity (freezing process, affected by concurrent changes of temperature, salinity, and ice formation. An anomalous induced polarization response was first observed during the transient period of supercooling and the onset of ice nucleation. Seismic measurements showed a characteristic maximal attenuation at the temperatures immediately below the freezing point, followed by a decrease with decreasing temperature. The calculated elastic moduli showed a non-hysteric response during the freeze - thaw cycle, which was different from the concurrently measured electrical resistivity response where a differential resistivity signal is observed depending on whether the soil is experiencing freezing or thawing. The differential electrical resistivity signal presents challenges for unfrozen water content estimation based on Archie's law. Using an improved formulation of Archie's law with a variable cementation exponent, the unfrozen water content estimation showed a large variation depending on the choice of the resistivity data during either a freezing or thawing cycle. Combining the electrical and seismic results, we suggest that, rather than a large hysteresis in the actual unfrozen water content, the shift of the resistivity response may reflect the changes of the distribution pattern of the unfrozen water (or ice) in the soil matrix during repeated freeze and thaw processes. Collectively, our results provide an improved petrophysical understanding of the physical and mechanical properties of saline permafrost during freeze - thaw transitions, and suggest that large uncertainty may exist when estimating the unfrozen water content using electrical resistivity data.

  20. Analysis of the Dielectric Constant of Saline-Alkali Soils and the Effect on Radar Backscattering Coefficient: A Case Study of Soda Alkaline Saline Soils in Western Jilin Province Using RADARSAT-2 Data

    Science.gov (United States)

    Li, Yang-yang; Zhao, Kai; Ren, Jian-hua; Ding, Yan-ling; Wu, Li-li

    2014-01-01

    Soil salinity is a global problem, especially in developing countries, which affects the environment and productivity of agriculture areas. Salt has a significant effect on the complex dielectric constant of wet soil. However, there is no suitable model to describe the variation in the backscattering coefficient due to changes in soil salinity content. The purpose of this paper is to use backscattering models to understand behaviors of the backscattering coefficient in saline soils based on the analysis of its dielectric constant. The effects of moisture and salinity on the dielectric constant by combined Dobson mixing model and seawater dielectric constant model are analyzed, and the backscattering coefficient is then simulated using the AIEM. Simultaneously, laboratory measurements were performed on ground samples. The frequency effect of the laboratory results was not the same as the simulated results. The frequency dependence of the ionic conductivity of an electrolyte solution is influenced by the ion's components. Finally, the simulated backscattering coefficients measured from the dielectric constant with the AIEM were analyzed using the extracted backscattering coefficient from the RADARSAT-2 image. The results show that RADARSAT-2 is potentially able to measure soil salinity; however, the mixed pixel problem needs to be more thoroughly considered. PMID:25101317

  1. Isolation and identification of myxobacteria from saline-alkaline soils in Xinjiang, China.

    Directory of Open Access Journals (Sweden)

    Xianjiao Zhang

    Full Text Available Fifty-eight terrestrial and salt-tolerant myxobacteria were isolated from the saline-alkaline soils collected from Xinjiang, China. Based on the morphologies and the 16S rRNA gene sequences, these isolates were assigned into 6 genera, Myxococcus, Cystobacter, Corallococcus, Sorangium, Nannocystis and Polyangium. All the strains grew better with 1% NaCl than without NaCl. Some Myxococcus strains were able to grow at 2% NaCl concentration, suggesting that these strains may be particular type of terrestrial myxobacteria.

  2. Preceding crop affects grain cadmium and zinc of wheat grown in saline soils of central Iran.

    Science.gov (United States)

    Khoshgoftarmanesh, Amir H; Chaney, Rufus L

    2007-01-01

    Enhanced Cd concentrations in wheat (Triticum aestivum L.) grain produced on saline soils of central Iran have been recently reported. Because wheat bread is a major dietary component for the Iranian people, practical approaches to decrease Cd concentration in wheat grain were investigated. This study investigated the influence of sunflower-wheat vs. cotton-wheat rotations on extractable Cd and on Cd uptake by wheat in these salt-affected soils. Two fields with different levels of Cd contamination (1.5 and 3.2 mg total Cd kg(-1) dry soil) were cropped with different rotations (cotton-wheat and sunflower-wheat) in Qom province, central Iran. Seeds of cotton (Gossypium L.) or sunflower (Helianthus annuus L. cv. Record) were planted in plots. After harvesting of the plants and removal of crop residues, wheat (cv. Rushan) was seeded in all plots. For both studied soils, the concentrations of Cd extracted by 0.04 M EDTA and 1 M CaCl(2) were significantly (P sunflower. Accordingly, the total amount of Cd in sunflower shoot was significantly (P sunflower were significantly different; wheat shoots after cotton accumulated more Cd (two to four times) than after sunflower. Wheat grain Cd concentration after sunflower was much lower (more than seven times) than after cotton. The results of this study showed that sunflower in rotation with wheat in salt-affected soils of central Iran significantly reduced the risk of Cd transfer to wheat grain.

  3. Effects of Soil Salinity on the Expression of Bt Toxin (Cry1Ac and the Control Efficiency of Helicoverpa armigera in Field-Grown Transgenic Bt Cotton.

    Directory of Open Access Journals (Sweden)

    Jun-Yu Luo

    Full Text Available An increasing area of transgenic Bacillus thuringiensis (Bt cotton is being planted in saline-alkaline soil in China. The Bt protein level in transgenic cotton plants and its control efficiency can be affected by abiotic stress, including high temperature, water deficiency and other factors. However, how soil salinity affects the expression of Bt protein, thus influencing the control efficiency of Bt cotton against the cotton bollworm (CBW Helicoverpa armigera (Hübner in the field, is poorly understood. Our objective in the present study was to investigate the effects of soil salinity on the expression of Bt toxin (Cry1Ac and the control efficiency of Helicoverpa armigera in field-grown transgenic Bt cotton using three natural saline levels (1.15 dS m-1 [low soil-salinity], 6.00 dS m-1 [medium soil-salinity] and 11.46 dS m-1 [high soil-salinity]. We found that the Bt protein content in the transgenic Bt cotton leaves and the insecticidal activity of Bt cotton against CBW decreased with the increasing soil salinity in laboratory experiments during the growing season. The Bt protein content of Bt cotton leaves in the laboratory were negatively correlated with the salinity level. The CBW populations were highest on the Bt cotton grown in medium-salinity soil instead of the high-salinity soil in field conditions. A possible mechanism may be that the relatively high-salinity soil changed the plant nutritional quality or other plant defensive traits. The results from this study may help to identify more appropriate practices to control CBW in Bt cotton fields with different soil salinity levels.

  4. Effects of Soil Salinity on the Expression of Bt Toxin (Cry1Ac) and the Control Efficiency of Helicoverpa armigera in Field-Grown Transgenic Bt Cotton.

    Science.gov (United States)

    Luo, Jun-Yu; Zhang, Shuai; Peng, Jun; Zhu, Xiang-Zhen; Lv, Li-Min; Wang, Chun-Yi; Li, Chun-Hua; Zhou, Zhi-Guo; Cui, Jin-Jie

    2017-01-01

    An increasing area of transgenic Bacillus thuringiensis (Bt) cotton is being planted in saline-alkaline soil in China. The Bt protein level in transgenic cotton plants and its control efficiency can be affected by abiotic stress, including high temperature, water deficiency and other factors. However, how soil salinity affects the expression of Bt protein, thus influencing the control efficiency of Bt cotton against the cotton bollworm (CBW) Helicoverpa armigera (Hübner) in the field, is poorly understood. Our objective in the present study was to investigate the effects of soil salinity on the expression of Bt toxin (Cry1Ac) and the control efficiency of Helicoverpa armigera in field-grown transgenic Bt cotton using three natural saline levels (1.15 dS m-1 [low soil-salinity], 6.00 dS m-1 [medium soil-salinity] and 11.46 dS m-1 [high soil-salinity]). We found that the Bt protein content in the transgenic Bt cotton leaves and the insecticidal activity of Bt cotton against CBW decreased with the increasing soil salinity in laboratory experiments during the growing season. The Bt protein content of Bt cotton leaves in the laboratory were negatively correlated with the salinity level. The CBW populations were highest on the Bt cotton grown in medium-salinity soil instead of the high-salinity soil in field conditions. A possible mechanism may be that the relatively high-salinity soil changed the plant nutritional quality or other plant defensive traits. The results from this study may help to identify more appropriate practices to control CBW in Bt cotton fields with different soil salinity levels.

  5. Response of rice advance line PB-95 to potassium application in saline-sodic soil.

    Science.gov (United States)

    Mehdi, Shahzada Munawar; Sarfraz, Muhammad; Hafeez, Mudassar

    2007-09-01

    A field experiment was conducted to evaluate the response of rice crop to potassium fertilization in saline-sodic soil during 2005. Soil samples were collected before transplanting of rice crop and analysed for physical and chemical properties of the soil. In this experiment five rates of K2O (0, 25, 50, 75 and 100 kg ha(-1)) were applied in the presence of basal doses of N and P2O5 i.e., 110 and 90 kg ha(-1), respectively. Whole of P, K and 1/2 of N were applied at the time of rice transplanting. Twelve and halfkg ha(-1) ZnSO4 was also applied 15 days after rice transplanting. The remaining half of N was applied 30 days after rice transplanting. The system of layout was Randomized Complete Block Design with four replications. The net plot size was 6x4 m. Fertilizer sources of NPK were urea, TSP and SOP, respectively. Rice salt tolerant line PB-95 was used as test crops. The data of growth parameters and yield was recorded and samples of paddy and straw were collected treatment-wise and analysed for N, P and K contents. Soil samples after harvesting the crop were also collected, processed and analysed for the changes in the extractable soil K. The results showed that increasing rates of potassium fertilizer increased the number of tillers m(-2), plant height (cm), 1000-paddy weight and paddy as well as straw yield significantly. Maximum paddy (3.24 t ha(-1)) and straw (3.92 t ha(-1)) yields were obtained in T5 (100 kg K2O ha(-1)) which was at par with T4 (75 kg K2O ha(-1)). With increasing rates of potassium fertilizer, concentration of potassium in paddy and straw increased significantly. After harvesting the crop, the extractable potassium contents of soil increased from that of the original soil. It was concluded from the results that there was an increase of 30.65% in paddy over control by applying potassium (100 kg K2O ha(-1)) in saline-sodic soil.

  6. Production of peptide antibiotics by Bacillus sp: GU 057 indigenously isolated from saline soil

    Directory of Open Access Journals (Sweden)

    Adnan Amin

    2012-12-01

    Full Text Available A total of 112 soil samples were taken from differents areas of district D.I.Khan and Kohat (KPK Pakistan and screened for production of antibiotics against the Micrococcus luteus and Staphylococcus aureus. Widest zone of inhibition (18mm was produced by microorganism isolated from saline soil. The strain was later identified as Bacillus GU057 by standard biochemical assays. Maximum activity (18mm inhibition zone was observed against Staphylococcus aureus after 48 hours of incubation at pH 8 and 4% concentration of glucose. The antibiotic was identified by autobiography as bacitracin. The Bacillus strain GU057 was confirmed as good peptide antibiotic producer and can effectively be indulged as biocontrol agent.

  7. Modeling and Mapping of Soil Salinity with Reflectance Spectroscopy and Landsat Data Using Two Quantitative Methods (PLSR and MARS

    Directory of Open Access Journals (Sweden)

    Said Nawar

    2014-11-01

    Full Text Available The monitoring of soil salinity levels is necessary for the prevention and mitigation of land degradation in arid environments. To assess the potential of remote sensing in estimating and mapping soil salinity in the El-Tina Plain, Sinai, Egypt, two predictive models were constructed based on the measured soil electrical conductivity (ECe and laboratory soil reflectance spectra resampled to Landsat sensor’s resolution. The models used were partial least squares regression (PLSR and multivariate adaptive regression splines (MARS. The results indicated that a good prediction of the soil salinity can be made based on the MARS model (R2 = 0.73, RMSE = 6.53, and ratio of performance to deviation (RPD = 1.96, which performed better than the PLSR model (R2 = 0.70, RMSE = 6.95, and RPD = 1.82. The models were subsequently applied on a pixel-by-pixel basis to the reflectance values derived from two Landsat images (2006 and 2012 to generate quantitative maps of the soil salinity. The resulting maps were validated successfully for 37 and 26 sampling points for 2006 and 2012, respectively, with R2 = 0.72 and 0.74 for 2006 and 2012, respectively, for the MARS model, and R2 = 0.71 and 0.73 for 2006 and 2012, respectively, for the PLSR model. The results indicated that MARS is a more suitable technique than PLSR for the estimation and mapping of soil salinity, especially in areas with high levels of salinity. The method developed in this paper can be used for other satellite data, like those provided by Landsat 8, and can be applied in other arid and semi-arid environments.

  8. Soil salinity and water productivity of carrot-millet system as influenced by irrigation regimes with saline water in arid regions of Tunisia

    Directory of Open Access Journals (Sweden)

    Fathia - El Mokh

    2013-12-01

    Full Text Available Field studies were conducted for three years to determine the effects of irrigation regimes with saline water (3.6 dS/m on soil salinity, yield and water productivity of carrot and millet under actual commercial-farming conditions in the arid region of Tunisia. Carrot and millet were grown during fall-winter and summer seasons on a sandy soil and surface and drip-irrigated with well water having an ECi of 3.6 dS/m. For three years, a complete randomized block design with four replicates was used to evaluate five irrigation regimes. Irrigation regimes consisted in water replacements of cumulated ETc at levels of 100% (SWB100, full irrigation, 80% (DI-80, 60% (DI-60, when the readily available water in SWB100 treatment is depleted, deficit irrigation during ripening stage (SWB100-DI60 and farmer method corresponding to irrigation practices implemented by the local farmers. The results showed that soil salinity was significantly affected by irrigation treatments. Higher soil salinity was maintained in the root zone with DI-60 and farmer irrigation treatments than full irrigation (SWB100. SWB100-DI60 and DI-80 treatments resulted also in low ECe values. Soil salinity was kept within acceptable limits for the growth of the crops grown in the rotation when SWB100, SWB100-DI60 and DI-80 strategies were employed. The rainfalls received during fall-winter and spring periods were effective in leaching salts from the soil profile. During the three year period, carrot and millet yield was highest for the SWB100 full treatment, (29.5, 28.7 and 26.8 t/ha for carrot and 27.2, 28.3 and 26.9 q/ha for millet although no significant differences were observed with the regulated deficit irrigation treatment (SWB100-DI60. However, the DI-80 and DI-60 deficit irrigation treatments caused significant reductions in carrot and millet yields through a reduction in roots number and weight, panicle number, kernel number and weight in comparison with SWB100. The farmer

  9. Natural radioactivity hazards of building bricks fabricated from saline soil of two districts of Pakistan.

    Science.gov (United States)

    Tufail, M; Nasim-Akhtar; Sabiha-Javied; Hamid, Tehsin

    2007-12-01

    Primordial radionuclides in building materials are one of the sources of radiation hazard in dwellings made of those materials. Activity concentrations of primordial radionuclides 40K, 226Ra and 232Th have been measured in house building bricks fabricated from saline soil. Forty samples of the bricks were collected from the brick fabrication sites and brick baking kilns in and around the saline soil areas of the districts of Lahore and Faisalabad in the Punjab province of Pakistan. The technique of gamma-ray spectroscopy using an HPGe detector with a PC-based multi-channel analyser was applied for determination of activity concentrations in the brick samples. The activity mass concentrations of 40K, 226Ra and 232Th measured in the brick samples were respectively 567.7 +/- 38.3 (493-631), 28.4 +/- 3.8 (23-35), and 56.0 +/- 4.6 (46-65) Bq kg(-1). The radiological hazards of the bricks were calculated using various models given in the literature. The radium equivalent activity was less than the accepted standard criterion value of 370 Bq kg(-1) and the values of other hazard indices were also below their limit values. The radiological hazard parameters of the bricks under investigation have been compared with those from other locations of Pakistan and also from some other countries in Asia.

  10. Impacts of seawater intrusion on soil salinity and alkalinity in Bafra Plain, Turkey.

    Science.gov (United States)

    Arslan, Hakan; Demir, Yusuf

    2013-02-01

    This study was carried out to investigate possible seawater intrusion into groundwater along the coastal lines of the Bafra Plain and salinity-alkalinity problems over land areas irrigated with water exposed to seawater intrusion were evaluated. For this purpose, 32 groundwater wells were selected over the plain, water samples were taken from these wells between October 2007 and September 2008, and chemical analyses were performed over these samples. Soil samples were taken from the fields irrigated with this water at 32 different locations at the end of the irrigation season in September 2008 from 0-30, 30-60, 60-90, and 90-120 cm soil depths and textures. EC, pH, Na, Ca, Mg, and K analyses were performed over these samples. Excessive seawater intrusion was observed in some parts of the plain and impacts of seawater intrusion decreased with the distance from the coastal line. It was determined that groundwater quality was significantly affected from seawater intrusion. Salinity and especially alkalinity problems were observed in land areas irrigated with this water and alkalinity increased with the rate of intrusion.

  11. Effects of Soil Salinization and Waterlogging on the Concentrations of Some Macronutrients and Sodium in Corn Root

    OpenAIRE

    N Najafi

    2015-01-01

    Salinity and waterlogging are two abiotic stresses decrease plants yield. In this research, the effects of soil salinization and waterlogging having concentrations of calcium (Ca), potassium (K), magnesium (Mg) and sodium (Na) and K:Na ratio in corn (Zea mays cv. single cross 704) root were studied under greenhouse conditions. A factorial experiment with two factors on the basis of completely randomized design with three replications was performed. The factors under study were: waterlogging d...

  12. Soil-plant interrelations: the significance of soil degradation and the risk assessment methodology for salinization

    NARCIS (Netherlands)

    Hagyó, A.; Tóth, T.; Bloem, E.; Zee, van der S.E.A.T.M.; Horváth, E.

    2008-01-01

    Numerous methodologies are used in the EU Member States to assess the risk for different soil threats related to various agricultural practices (erosion, salinisation, organic matter decline, compaction and landslides). Our aim was to evaluate the risk assessment methodologies (RAMs) utilized for

  13. Salinization and Saline Environments

    Science.gov (United States)

    Vengosh, A.

    2003-12-01

    One of the most conspicuous phenomena of water-quality degradation, particularly in arid and semi-arid zones, is salinization of water and soil resources. Salinization is a long-term phenomenon, and during the last century many aquifers and river basins have become unsuitable for human consumption owing to high levels of salinity. Future exploitation of thousands of wells in the Middle East and in many other water-scarce regions in the world depends, to a large extent, on the degree and rate of salinization. Moreover, every year a large fraction of agricultural land is salinized and becomes unusable.Salinization is a global environmental phenomenon that affects many different aspects of our life (Williams, 2001a, b): changing the chemical composition of natural water resources (lakes, rivers, and groundwater), degrading the quality of water supply to the domestic and agriculture sectors, contribution to loss of biodiversity, taxonomic replacement by halotolerant species ( Williams, 2001a, b), loss of fertile soil, collapse of agricultural and fishery industries, changing of local climatic conditions, and creating severe health problems (e.g., the Aral Basin). The damage due to salinity in the Colorado River Basin alone, for example, ranges between 500 and 750 million per year and could exceed 1 billion per year if the salinity in the Imperial Dam increases from 700 mg L-1 to 900 mg L-1 (Bureau of Reclamation, 2003, USA). In Australia, accelerating soil salinization has become a massive environmental and economic disaster. Western Australia is "losing an area equal to one football oval an hour" due to spreading salinity ( Murphy, 1999). The annual cost for dryland salinity in Australia is estimated as AU700 million for lost land and AU$130 million for lost production ( Williams et al., 2002). In short, the salinization process has become pervasive.Salinity in water is usually defined by the chloride content (mg L-1) or total dissolved solids content (TDS, mg L-1or g

  14. Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

    Directory of Open Access Journals (Sweden)

    K. Z. Jadoon

    2017-10-01

    Full Text Available A substantial interpretation of electromagnetic induction (EMI measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes' rule. The electromagnetic forward model based on the full solution of Maxwell's equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

  15. Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

    Science.gov (United States)

    Zaib Jadoon, Khan; Umer Altaf, Muhammad; McCabe, Matthew Francis; Hoteit, Ibrahim; Muhammad, Nisar; Moghadas, Davood; Weihermüller, Lutz

    2017-10-01

    A substantial interpretation of electromagnetic induction (EMI) measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC) algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes' rule. The electromagnetic forward model based on the full solution of Maxwell's equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

  16. Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

    KAUST Repository

    Jadoon, Khan Zaib

    2017-10-26

    A substantial interpretation of electromagnetic induction (EMI) measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC) algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes\\' rule. The electromagnetic forward model based on the full solution of Maxwell\\'s equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

  17. High-resolution model for estimating the economic and policy implications of agricultural soil salinization in California

    Science.gov (United States)

    Welle, Paul D.; Mauter, Meagan S.

    2017-09-01

    This work introduces a generalizable approach for estimating the field-scale agricultural yield losses due to soil salinization. When integrated with regional data on crop yields and prices, this model provides high-resolution estimates for revenue losses over large agricultural regions. These methods account for the uncertainty inherent in model inputs derived from satellites, experimental field data, and interpreted model results. We apply this method to estimate the effect of soil salinity on agricultural outputs in California, performing the analysis with both high-resolution (i.e. field scale) and low-resolution (i.e. county-scale) data sources to highlight the importance of spatial resolution in agricultural analysis. We estimate that soil salinity reduced agricultural revenues by 3.7 billion (1.7-7.0 billion) in 2014, amounting to 8.0 million tons of lost production relative to soil salinities below the crop-specific thresholds. When using low-resolution data sources, we find that the costs of salinization are underestimated by a factor of three. These results highlight the need for high-resolution data in agro-environmental assessment as well as the challenges associated with their integration.

  18. Investigating the Relationship between Evapotranspiration and Soil Salinity Using a Surface Energy Balance Model (ReSET).

    Science.gov (United States)

    Garcia, L. A.; Elhaddad, A.

    2008-12-01

    Reliable estimates of evapotranspiration (ET) from vegetation are needed for many types of water-resource investigations. This presentation introduces an enhanced surface energy balance-based model, the Remote Sensing of Evapotranspiration or ReSET model, for estimating ET. ReSET is an ET estimation model that takes into consideration the spatial variability in weather parameters, which makes it particularly applicable for calculating regional scale ET. ReSET also has the capability of interpolating between the available weather stations in time and space. The model's accuracy at daily and seasonal time scales is evaluated in several case studies. A special application of the model to investigate the relationship between ET and soil salinity in agricultural areas is presented. The case study focuses on the impacts of salinity on ET in corn and alfalfa in the Lower Arkansas River Basin in Colorado during the period 1999 to 2007. Evapotranspiration values were regressed against the spatially corresponding soil salinity values to develop a relation between ET and soil salinity. The ET values correlate well with the soil salinity levels in the study region, with a correlation coefficient of up to 0.86.

  19. Evaluation of the halophyte Salsola soda as an alternative crop for saline soils high in selenium and boron.

    Science.gov (United States)

    Centofanti, Tiziana; Bañuelos, Gary

    2015-07-01

    Urbanization, industrial development, and intensive agriculture have caused soil contamination and land degradation in many areas of the world. Salinization is one important factor contributing to land degradation and it affects agricultural production and environmental quality. When salinization is combined with soil pollution by trace elements, as it occurs in many arid and semi-arid regions around the world, strategies to phyto-manage pollutants and sustain crop production need to be implemented. In this study, we present the case of saline soils in the West side of Central California which contain naturally-occurring selenium (Se), boron (B), and other salts, such as NaCl, CaCl2, Na2SO4, and Na2SeO4. To sustain crop production on Se- and B-laden arid saline soils, we investigated the potential of the halophyte "agretti" (Salsola soda L.) as an alternative crop. The aim of our greenhouse study was to examine adaptability, B tolerance, and Se accumulation by S. soda grown on soils collected from a typical saline-laden field site located on the West side of the San Joaquin Valley (SJV). Our results showed that S. soda tolerates the saline (EC ∼ 10 dS m(-1)) and B-laden soils (10 mg B L(-1)) of the SJV even with the additional irrigation of saline and B rich water (EC ∼ 3 dS m(-1) and 4 mg B L(-1)). Under these growing conditions, the plant can accumulate high concentrations of Na (80 g Na kg(-1) DW), B (100 mg B kg(-1) DW), and Se (3-4 mg Se kg(-1) DW) without showing toxicity symptoms. Hence, S. soda showed promising potential as a plant species that can be grown in B-laden saline soils and accumulate and potentially manage excessive soluble Se and B in soil. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. An inorganic CO2 diffusion and dissolution process explains negative CO2 fluxes in saline/alkaline soils

    Science.gov (United States)

    Ma, Jie; Wang, Zhong-Yuan; Stevenson, Bryan A.; Zheng, Xin-Jun; Li, Yan

    2013-01-01

    An ‘anomalous' negative flux, in which carbon dioxide (CO2) enters rather than is released from the ground, was studied in a saline/alkaline soil. Soil sterilization disclosed an inorganic process of CO2 dissolution into (during the night) and out of (during the day) the soil solution, driven by variation in soil temperature. Experimental and modeling analysis revealed that pH and soil moisture were the most important determinants of the magnitude of this inorganic CO2 flux. In the extreme cases of air-dried saline/alkaline soils, this inorganic process was predominant. While the diurnal flux measured was zero sum, leaching of the dissolved inorganic carbon in the soil solution could potentially effect net carbon ecosystem exchange. This finding implies that an inorganic module should be incorporated when dealing with the CO2 flux of saline/alkaline land. Neglecting this inorganic flux may induce erroneous or misleading conclusions in interpreting CO2 fluxes of these ecosystems. PMID:23778238

  1. Determination of Nutrient Contents and Gas Production Values of Some Legume Forages Grown in the Harran Plain Saline Soils

    Directory of Open Access Journals (Sweden)

    M. Boga

    2014-06-01

    Full Text Available The aim of this study was to determine the nutritive value of some legume species in salt-affected soils of South-East Anatolian region using chemical composition and in vitro gas production kinetics. In this study, Lotus corniculatus, Trifolium alexandrinum, Medicago sativa were sown and tested in four different locations. A 3 by 4 factorial design with 3 legume species and 4 salt levels (non salty electrical conductivity (ECECECEC was used in the study. Results indicated that salinity and plants had no significant effect on ash and ether extract. Dry matter (DM, acid detergent fiber, digestible dry matter, dry matter intake (DMI were affected by plant, salinity and plant×salinity interaction. On the other hand neutral detergent fiber, relative feed value (RFV, and DMI were affected by salinity and plant×salinity interaction. Mineral contents were affected by plant species, salinity and salinity×plants interactions. In vitro gas production, their kinetics and estimated parameters such as were not affected by salinity whereas the gas production up to 48 h, organic matter digestibility, metabolizable energy (ME, and net energy lactation (NEL were affected by plant and plant×salt interaction. Generally RFVs of all species ranged from 120 to 210 and were quite satisfactory in salty conditions. Current results show that the feed value of Medicago sativa is higher compared to Lotus corniculatus and Trifolium alexandrinum.

  2. Recent advances in the salinity retrieval algorithms for Aquarius and Soil Moisture Active Passive (SMAP)

    Science.gov (United States)

    Meissner, Thomas; Wentz, Frank; Lee, Tong

    2017-04-01

    Our presentation discusses the latest improvements in the salinity retrievals both for Aquarius and Soil Moisture Active-Passive (SMAP) since the last releases. The Aquarius V4.0 was released in June 2015. The final V5.0 release is planned for late 2017. SMAP V 2.0 has been released in September 2016. We will present validation results for both Aquarius V5.0 pre-release and SMAP V2.0 salinity comparing with near-surface salinity measurements from Argo floats. We show that salty biases at higher northern latitudes in Aquarius V4.0 can be explained by inaccuracy in the model used in correcting for the absorption by atmospheric oxygen. These biases will be mitigated in V5.0 by fine-tuning the parameters in the oxygen absorption model. The full 360-degree look capability of SMAP makes it possible to take observations from the forward and backward looking direction at the same instance of time. This two-look capability aids the salinity retrievals. One of the largest spurious contaminations in the salinity retrievals is caused by the galactic reflection from the ocean surface. Because in most instances the reflected galaxy appears only in either the forward or the backward look, it is possible to determine its contribution by taking the difference of the measured SMAP brightness temperatures between the two looks. Our result suggests that the surface roughness that is used in the galactic correction needs to be increased and also the estimated strength of some of the galactic sources need to be slightly adjusted. The improved galaxy correction has been implemented in SMAP V2.0 retrieval and will be included in Aquarius V5.0 as well. It helps the mitigation of residual zonal and temporal biases that were present in both products. Another major cause of the observed zonal biases in SMAP is the emissive SMAP mesh antenna. In order to correct for it, an accurate knowledge of the emissivity of the antenna and its physical temperature are required. We discuss the improvements

  3. Reclaiming Saline-Sodic Soils Using Electrochemical Processes: A Case Study From Sahl El-Tina Plain, Egypt

    Directory of Open Access Journals (Sweden)

    Abdel-Fattah Mohamed K.

    2014-10-01

    Full Text Available A leaching experiment was conducted using column techniques assessing efficiency of electrochemical process to reclaim saline-sodic soils. Soil material was collected from Sahl El-Tina plain, which located in North West coast of Sinai, Egypt. The experiment was designed as factorial randomized complete block and all treatments were replicated three times. Two 2.5 cm diameterx30 cm height mild stainless steel tubes were inserted into the soil matrix to serve as electrodes (i.e. cathode and anode. Distance between cathode and anode was 10 cm. Electrodes were supplied by a direct current (DC power supply; Volt ages of 0.3 or 9 Volt. Leaching was done using the intermittent method so as to add portions to the already saturated soil columns, and obtain leachates equal to the added portions. Pore volume 0.1 PV was used in the leaching processes which are equal 498.4 cm3, i.e. PV being volume of pores per column, thus 1 PV equals volume of pores (cm3 expressed as water quantity. Electric remediation increased ionic mobility and separated salts from soil. All treatments decreased soil EC and soil sodicity expressed as SAR and ESP. Results showed that 9 Volt treatment was more effective in decreasing the soil EC and soil sodicity than the other treatments. Efficiency of treatments were 9-Volt > 3-Volt > leaching alone (non-DC treatment. This study suggests that leaching using direct current (DC led to improvement of the chemical properties of saline sodic soils and required a short time to reclaim saline-sodic soils compared with leaching alone.

  4. Updates on Water Use of Pistachio Orchards Grown in the San Joaquin Valley of California on Saline Soils

    Science.gov (United States)

    Zaccaria, Daniele; Marino, Giulia; Whiting, Michael; Sanden, Blake; Ferguson, Louise; Lampinen, Bruce; Kent, Eric; Snyder, Richard; Grattan, Stephen; Little, Cayle

    2017-04-01

    Pistachio acreage is rapidly expanding in California thanks to its economic profitability and capacity to grow and produce in salt-affected soils. Our team at University of California is updating information on actual water use (ET) of mature pistachio orchards grown on saline soils under micro-irrigation methods. Actual Evapotranspiration (ETa) and Crop Coefficients (Ka) were determined for the 2015 and 2016 crop seasons on four pistachio orchards grown in the San Joaquin Valley (SJV) on grounds with increasing levels of soil-water salinity, using the residual of energy balance method with a combination of eddy covariance and surface renewal equipment. Tree canopy cover, light interception, and plant water status across the orchards were also measured and evaluated. Our preliminary results show that salinity strongly affects the tree water use, resulting in 10-30% less ET for medium to high salt-affected soils. Salinity also showed a strong effect on tree water status and light interception, as suggested by values of the Midday Stem Water Potential (ΨSWP) around 10 to 15-bar lower in salt-affected than in the control orchard, and by the intercepted Photosynthetic Active Radiation (PAR) decreasing from 75% in the control orchard to 25% in the severely salt affected grounds. The crop coefficient values we observed in this study are lower than those commonly used for irrigation scheduling in the SJV, suggesting that pistachio growers could better tailor irrigation management to the actual site-specific orchard conditions (e.g. canopy features and soil-water salinity) if they are provided updated information. Improved irrigation practices could likely lead to significant water savings and thus improve the resource-efficiency and competitiveness of pistachio production in the SJV. Keywords: Pistacia vera L., salinity, stem water potential, surface renewal, canopy cover.

  5. Distribution of ion contents and microorganisms during the electro-bioremediation of petroleum-contaminated saline soil.

    Science.gov (United States)

    Zhang, Meng; Guo, Shuhai; Li, Fengmei; Wu, Bo

    2017-10-15

    This study investigated the distribution of ion contents and microorganisms during the electro-bioremediation (EK-Bio) of petroleum-contaminated saline soil. The results showed that soil ions tend to accumulate around the electrodes, and the concentration was correlated with the distance from the electrodes. The average soil ion content was 7.92 g/kg around the electrodes (site A) and 0.55 g/kg at the furthest distance from the electrodes (site B) after 112 days of treatment, while the initial average content was 3.92 g/kg. Smooth linear (R2 = 0.98) loss of soil ions was observed at site C, which was closer to the electrodes than site B, and had a final average soil ion content of 1.96 g/kg. The dehydrogenase activity was much higher in EK-Bio test soil than in the Bio test soil after 28 days of treatment, and followed the order: site C > site B > site A. However, the soil dehydrogenase activity dropped continuously when the soil ion reached very high and low concentrations at sites A and B. The soil microbial community varied in sample sites that had different ion contents, and the soil microbial diversity followed the order: site C > site B > site A. The applied electric field clearly enhanced the biodegradation efficiency for soil petroleum contaminants. However, the biodegradation promotion effects were weakening in soils where the ion contents were extremely high and low (sites A and B). These results can provide useful information for EK-Bioremediation of organic-contaminated saline soil.

  6. Effects of rhizobial bacteria on K, Ca and Na concentration of wheat (Triticum aestivum L. in saline soils

    Directory of Open Access Journals (Sweden)

    S homayoon

    2016-05-01

    Full Text Available Introduction Soil salinity is one of the major agricultural problems and it is limiting crop productivity in many parts of the cultivated areas all over the world. Saline soils are differentiated by the presence of great ratios of Na/Ca, Na/K, Ca2+, Mg2+, and Cl/NO3 (Gratan & Catherine, 1993 and high levels of neutral salts in the surface layers, which are resulting from the capillary action (Al-Falih, 2002. Osmotic stress occurs when soluble salts increase in the soils and then results in specific ion toxicity (Agarwal & Ahmad, 2010. Therefore, one of the most important side effects of salinity is nutritional disorders. High concentration of NaCl in the root medium usually reduces nutrients uptake and affects the transportation of potassium and calcium ions in plant. (Gratan & Catherine, 1993 reported that the salinity of soils changes ionic strength of the substrate and it can influence mineral nutrient uptake and translocation. Salinity also changes the mineral nutrient availability and disrupts the mineral relations of plants. Hence, the main purpose of this research is to evaluate the effects of rhizobial bacteria inoculation on K, Ca and Na concentration of wheat (Triticum aestivum L. in saline soils. Material and methods Soil sample was collected from Astan Ghodse Razavi farm, Mashhad Iran, and then was dried and passed through a 12-mesh (approximately 2 mm screen. Soil sample was divided into three parts and then was placed into three containers. Each container was watered by a different proportion of saline water (EC= 10 dS.m-1. Salinity of soils was regularly monitored until three salinities (2, 6 and 10 dS.m-1 came out. Then, a completely randomized design with a factorial arrangement was carried out in a greenhouse condition. The experimental factors included four levels of inoculation (Sinorhizobium meliloti, Bradyrhizobium japonicum and Rhizobium leguminosarum and control and three levels of soil salinity (2, 6 and 10 dS.m-1 with

  7. Numerical study of evaporation-induced salt accumulation and precipitation in bare saline soils: Mechanism and feedback

    Science.gov (United States)

    Zhang, Chenming; Li, Ling; Lockington, David

    2014-10-01

    Evaporation from bare saline soils in coastal wetlands causes salt precipitation in the form of efflorescence and subflorescence. However, it is not clear how much the precipitated salt in turn affects the water transport in the soil and hence the evaporation rate. We hypothesized that efflorescence exerts a mulching resistance to evaporation, while subflorescence reduces the pore space for water vapor to move through the soil. A numerical model is developed to simulate the transport of water, solute, and heat in the soil, and resulting evaporation and salt precipitation with the hypothesized feedback mechanism incorporated. The model was applied to simulate four evaporation experiments in soil columns with and without a fixed shallow water table, and was found to replicate well the experimental observations. The simulated results indicated that as long as the hydraulic connection between the near surface soil layer and the water source in the interior soil layer exists, vaporization occurs near the surface, and salt precipitates exclusively as efflorescence. When such hydraulic connection is absent, the vaporization plane develops downward and salt precipitates as subflorescence. Being more substantial in quantity, efflorescent affects more significantly evaporation than subflorescence during the soil-drying process. Different evaporation stages based on the location of the vaporization plane and the state of salt accumulation can be identified for characterizing the process of evaporation from bare saline soils with or without a fixed shallow water table.

  8. Aerial biomass and elemental changes in Atriplex canescens and A. acanthocarpa as affected by salinity and soil water availability

    Science.gov (United States)

    Ricardo Mata-Gonzalez; Ruben Melendez-Gonzalez; J. Jesus Martinez-Hernandez

    2001-01-01

    Atriplex canescens and A. acanthocarpa from the Chihuahuan Desert in Mexico were subjected to different salinity and irrigation treatments in a greenhouse study. Plants were grown in pots containing soil and irrigated with NaCl solutions of 0, 50, and 100 mM at 40 and 80 percent available soil water. Aerial biomass of A. canescens declined as NaCl treatments increased...

  9. Effects of Humic Acid-based Cation Buffer on Chemical Characteristics of Saline Soil and Growth of Maize

    OpenAIRE

    Mindari, W; N. Aini; Z Kusuma; Syekhfani, S

    2014-01-01

    Humic acid is believed to maintain the stability of the soil reaction, adsorption / fixation / cationic chelate, thereby increasing the availability of water and plant nutrients. On the other hand, the dynamics of saline soil cation is strongly influenced by the change of seasons that disrupt water and nutrient uptake of plants. This experiment was aimed to examine the characteristics of the humic acid from compost, coal, and peat and its function in the adsorption of cations (K+ and NH4+), t...

  10. Monitoring Soil Salinization in Keriya River Basin, Northwestern China Using Passive Reflective and Active Microwave Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Ilyas Nurmemet

    2015-07-01

    Full Text Available Soil salinization is one of the most widespread soil degradation processes on Earth, especially in arid and semi-arid areas. The salinized soil in arid to semi-arid Xinjiang Uyghur Autonomous Region in China accounts for 31% of the area of cultivated land, and thus it is pivotal for the sustainable agricultural development of the area to identify reliable and cost-effective methodologies to monitor the spatial and temporal variations in soil salinity. This objective was accomplished over the study area (Keriya River Basin, northwestern China by adopting technologies that heavily rely on, and integrate information contained in, a readily available suite of remote sensing datasets. The following procedures were conducted: (1 a selective principle component analysis (S-PCA fusion image was generated using Phased Array Type L-band SAR (PALSAR backscattering coefficient (σ° and Landsat Enhanced Thematic Mapper Plus (ETM+ multispectral image of Keriya River Basin; and (2 a support vector machines (SVM classification method was employed to classify land cover types with a focus on mapping salinized soils; (3 a cross-validation method was adopted to identify the optimum classification parameters, and obtain an optimal SVM classification model; (4 Radarsat-2 (C band and PALSAR polarimetric images were used to analyze polarimetric backscattering behaviors in relation to the variation in soil salinization; (5 a decision tree (DT scheme for multi-source optical and polarimetric SAR data integration was proposed to improve the estimation and monitoring accuracies of soil salinization; and (6 detailed field observations and ground truthing were used for validation of the adopted methodology, and quantity and allocation disagreement measures were applied to assess classification outcome. Results showed that the fusion of passive reflective and active microwave remote sensing data provided an effective tool in detecting soil salinization. Overall accuracy of

  11. Impact of soil salinity on the plant-growth – promoting and biological control abilities of root associated bacteria

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    Dilfuza Egamberdieva

    2017-11-01

    Full Text Available The effectiveness of plant growth – promoting bacteria is variable under different biotic and abiotic conditions. Abiotic factors may negatively affect the beneficial properties and efficiency of the introduced PGPR inoculants. The aim of this study was to evaluate the effect of plant growth – promoting rhizobacteria on plant growth and on the control of foot and root rot of tomatoes caused by Fusarium solani under different soil salinity conditions. Among the five tested strains, only Pseudomonas chlororaphis TSAU13, and Pseudomonas extremorientalis TSAU20 were able to stimulate plant growth and act as biological controls of foot and root rot disease of tomato. The soil salinity did not negatively affect the beneficial impacts of these strains, as they were able to colonize and survive on the roots of tomato plants under both saline and non-saline soil conditions. The improved plant height and fruit yield of tomato was also observed for plants inoculated with P. extremorientalis TSAU20. Our results indicated that, saline condition is not crucial factor in obtaining good performance with respect to the plant growth stimulating and biocontrol abilities of PGPR strains. The bacterial inoculant also enhanced antioxidant enzymes activities thereby preventing ROS induced oxidative damage in plants, and the proline concentrations in plant tissue that play an important role in plant stress tolerance.

  12. Identification of Soil Salinity Due to Seawater Intrusion on Rice Field in the Northern Coast of Indramayu, West Java

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    Deddy Erfandi

    2011-05-01

    Full Text Available The rice fields in Indramayu district is 55% of the district area. The average rainfall is 1590 mm per year. Most lands on the North Coast of Java (northern were potentially affected by sea water intrusion. Extensive observations were 102.321 ha. Field observations were done by survey method. Observations had been conducted on rice fields Pantura, Indramayu, West Java. Soil salinity was measured by using the electromagnetic conductivity meter (EM-38. The results revealed that area had very high salinity which was 22.57%, closest to the beach Indramayu. In the South Region, soil salinity was lower, in accordance with the distance from the coastline. Some areas had a low, medium, and high salinity status in which 58.41%, 8.54% and 10.49%, respectively. Much of the research area had very high Sodium (Na and ECe (0 - 30 cm was between 1.37 to 16.38 dS m-1, while the ECe (30 - 70 cm was between 1.11 to 17.40 dS m-1. This research was expected to assist in the agricultural development planning, especially in wetlands which have been affected by the intrusion of sea water (salinity. Planning for the implementation of the development of rice varieties that are sensitive to high and very high salinity. Planning and improvement of irrigation networks as sources of clean water for washing the salts or pushing salt water into the sea.

  13. Soil salinity: A serious environmental issue and plant growth promoting bacteria as one of the tools for its alleviation.

    Science.gov (United States)

    Shrivastava, Pooja; Kumar, Rajesh

    2015-03-01

    Salinity is one of the most brutal environmental factors limiting the productivity of crop plants because most of the crop plants are sensitive to salinity caused by high concentrations of salts in the soil, and the area of land affected by it is increasing day by day. For all important crops, average yields are only a fraction - somewhere between 20% and 50% of record yields; these losses are mostly due to drought and high soil salinity, environmental conditions which will worsen in many regions because of global climate change. A wide range of adaptations and mitigation strategies are required to cope with such impacts. Efficient resource management and crop/livestock improvement for evolving better breeds can help to overcome salinity stress. However, such strategies being long drawn and cost intensive, there is a need to develop simple and low cost biological methods for salinity stress management, which can be used on short term basis. Microorganisms could play a significant role in this respect, if we exploit their unique properties such as tolerance to saline conditions, genetic diversity, synthesis of compatible solutes, production of plant growth promoting hormones, bio-control potential, and their interaction with crop plants.

  14. The Relationship between Geological Factors and the Distribution of Saline Soil; a case study around Khon Kaen University, Thailand

    Science.gov (United States)

    Arjwech, Rungroj; Everett, Mark

    2017-04-01

    Distribution of saline soil and groundwater causes severe problems over many areas in Khon Kaen province, Thailand. Due to the change of land reclamation over years around and in Khon Kaen University causes evidents of saline groundwater to be not observed on the ground surface. In this study, data were collected from aerial photo interpretation, field studies, and the information of potassium mineral resource exploration in Khon Kaen. The ERT and VES geophysical methods were used to study distribution of saline groundwater over the campus. The results show that the distributions of saline soils are widely spread on meandering and flood plain in braided drainage areas. The ERT and VES studied on and around campus show that saline groundwater distributes over half of the campus through the South side. Its depth ranges between 5 and 30 m related to geomorphology; shallow on floodplain and deeper on the gentle terrain. However saline groundwater does not exist on the terrace. The distributions are natural occurrences and they are controlled by subsurface geological structures fractures geomorphology and geology.

  15. Crop and irrigation management strategies for saline-sodic soils and waters aimed at environmentally sustainable agriculture.

    Science.gov (United States)

    Qadir, M; Oster, J D

    2004-05-05

    Irrigation has long played a key role in feeding the expanding world population and is expected to play a still greater role in the future. As supplies of good-quality irrigation water are expected to decrease in several regions due to increased municipal-industrial-agricultural competition, available freshwater supplies need to be used more efficiently. In addition, reliance on the use and reuse of saline and/or sodic drainage waters, generated by irrigated agriculture, seems inevitable for irrigation. The same applies to salt-affected soils, which occupy more than 20% of the irrigated lands, and warrant attention for efficient, inexpensive and environmentally acceptable management. Technologically and from a management perspective, a couple of strategies have shown the potential to improve crop production under irrigated agriculture while minimizing the adverse environmental impacts. The first strategy, vegetative bioremediation--a plant-assisted reclamation approach--relies on growing appropriate plant species that can tolerate ambient soil salinity and sodicity levels during reclamation of salt-affected soils. A variety of plant species of agricultural significance have been found to be effective in sustainable reclamation of calcareous and moderately sodic and saline-sodic soils. The second strategy fosters dedicating soils to crop production systems where saline and/or sodic waters predominate and their disposal options are limited. Production systems based on salt-tolerant plant species using drainage waters may be sustainable with the potential of transforming such waters from an environmental burden into an economic asset. Such a strategy would encourage the disposal of drainage waters within the irrigated regions where they are generated rather than exporting these waters to other regions via discharge into main irrigation canals, local streams, or rivers. Being economically and environmentally sustainable, these strategies could be the key to future

  16. Faraday Rotation for SMOS Retrievals of Ocean Salinity and Soil Moisture

    Science.gov (United States)

    El-Nimri, Salem; Le Vine, David M.

    2016-08-01

    Faraday rotation is a change in polarization as radiation propagates from the surface through the ionosphere to the sensor. At L-band (1.4 GHz) this change can be significant and can be important for the remote sensing of soil moisture and ocean salinity from space. Consequently, modern L-band radiometers (SMOS, Aquarius and SMOS) are polarimetric to measure Faraday rotation "in situ" so that a correction can be made. This is done using the ratio of the third and second Stokes parameters. In the case of SMOS this procedure has produced very noisy estimates. An alternate procedure is reported here in which the total electron content is estimated and averaged to reduce noise.

  17. Partitioning of Chemical Constituents in the Leaf and Stover of Sorghum Grown in a Saline Soil

    Directory of Open Access Journals (Sweden)

    H.A. Esechie

    1996-01-01

    Full Text Available Field and laboratory studies were conducted in l990 and 1991 to determine the concentrations of total nonstructural carbohydrates (TNC, crude protein, cellulose,  hemicellulose. Iignin and ether extract partitioned in the leaf and stower of sorghum grown in a saline soil (EC = 11.8 dSm -1. Twenty three sorghum cultivars comprising 10 female lines. 6 male lines and 7 forage lines were used. TNC was uniformly distributed in the leaf and stover portions. Significantly higher concentrations of cellulose and Iignin were partitioned to the stover portions than the leaf, but the leaf contained larger amounts of hemicellulose and ether extract than the stover. Although, based on TNC contents some of the sorghum types have a potential for methanogenesis, the competing demand as animal feed also needs to be considered.

  18. Faraday Rotation for SMOS Retrievals of Ocean Salinity and Soil Moisture

    Science.gov (United States)

    El-Nimri, Salem; Le Vine, David M.

    2016-01-01

    Faraday rotation is a change in polarization as radiation propagates from the surface through the ionosphere to the sensor. At L-band (1.4 GHz) this change can be significant and can be important for the remote sensing of soil moisture and ocean salinity from space. Consequently, modern L-band radiometers (SMOS, Aquarius and SMOS) are polarimetric to measure Faraday rotation in situ so that a correction can be made. This is done using the ratio of the third and second Stokes parameters. In the case of SMOS this procedure has produced very noisy estimates. An alternate procedure is reported here in which the total electron content is estimated and averaged to reduce noise.

  19. Establishment of Tall Wheatgrass [Agropyron elongatum (Host) Beav. 'Jose'] and Basin Wildrye (Elymus cinereus Scribn. & Merr. 'Magnar') in Relation to Soil Water and Salinity

    OpenAIRE

    Roundy, Bruce A.

    1983-01-01

    The potential of basin wildrye (Elymus cinereus Scribn. & Merr. 'Magnar') and tall wheatgrass [Agropyron elongatum (Host) Beav. 'Jose '] to establish on saline, arid rangelands in the Great Basin in relation to soil water and salinity was compared in field and laboratory experiments. Tall wheatgrass had higher emergence and establishment on a nonsaline and a saline soil (electrical conductivity of the saturation extract of 7 dS·m-1) over a range of spring precipitation as simulated by sprinkl...

  20. [Quantitative retrieval of soil salinity using hyperspectral data in the region of inner Mongolia hetao irrigation district].

    Science.gov (United States)

    Qu, Yong-hua; Duan, Xiao-liang; Gao, Hong-yong; Chen, Ai-ping; An, Yong-qing; Song, Jin-ling; Zhou, Hong-min; He, Tao

    2009-05-01

    In the present paper, to investigate the spectral property of salinized soil and the relationship between the soil salinity and the hyperspectral data, the field soil samples were collected in the region of Hetao irrigation, Neimeng in the northwest China from the end of July to the beginning of August. The partial least squares regression (PLSR) model was established based on the statistical analysis of the soil ions and the reflectance of hyperspectra. The independent validation using data which are not included in the calibration model reveals that the proposed model can predicate the main soil components such as the content of total ions (S%), SO4(2+), PH and K+ + Na+ with higher determination coefficients (R2) Of 0.728, 0.801, 0.715 and 0.734 respectively. And the ratio of prediction to deviation (RPD) of the above predicted value is larger than 1.6, which indicates that the calibrated PLSR model can be used as a tool to retrieve soil salinity with accurate results. When the PLSR model's regression coefficients were aggregated according to the wavelength of visual (blue, green and red) and near infrared bands of LandSat Thematic Mapper(TM) sensor, some significant response values were observed, which indicates that the proposed method in this paper can be used to analyse the remotely sensed data from the space-boarded platform.

  1. Aerosol Particles from Dried Salt-Lakes and Saline Soils Carried on Dust Storms over Beijing

    Directory of Open Access Journals (Sweden)

    Xingying Zhang

    2009-01-01

    Full Text Available Characteristics of individual particles from a super dust storm (DS on 20 March 2002, and those of non dust storm aero sols for Beijing (NDS and Duolun (DL (a desert area are determined using a variety of methods. In China, typically the source of aero sols in dust storms is thought to be deserts with alumino silicates being the main constituent particles; how ever, this does not reflect a complete analysis with our evidence indicating potential alternate dust sources along the storm's trans port path. Individual particle anal y sis of aero sols collected from a super dust storm on 20 March 2002 in Beijing shows that among all the 14 elements measured, only S and Cl have re mark able positive correlation. 82.5% of all particles measured contained both S and Cl, and the relative mass per cent age of S and Cl in these particles is much higher than the average of all particles. 62.0% of all particles contained S, Cl, and Na, in which the concentration of Na is 1.4 times higher than average. PMF (Positive Matrix Factorization anal y sis indicates that NaCl and Na2SO4 are major components of these particles with S and Cl showing significant positive correlation. More over, SO4 2- and Cl- also show significant positive correlation in bulk aero sol analysis. XPS (X-ray Pho to electron Spectros copy analysis of the surface of aero sols demonstrates that concentrations of Na and S on particles from the dust storm are higher than those from non-dust storm particles in Beijing and also for particles from. It is very likely that particles enriched with S, Cl, and Na is from the surface soils of dried salt-lakes and saline soils enriched with chloride and sulfate. This evidence demonstrates that be sides deserts, surface soils from dry salt-lakes and saline soils of arid and semi-arid areas are also sources of particulates in dust storms over Beijing.

  2. Growth of cowpea plants inoculated with Rhizobium in a saline-sodic soil after application of gypsum

    Directory of Open Access Journals (Sweden)

    Angela Jessyka Pereira Brito Fontenele

    Full Text Available Two experiments were carried out with the aim of evaluating the growth of cowpea cultivated in saline-sodic soils corrected with gypsum: one experiment in the laboratory, to identify the best level of gypsum for the correction of the saline-sodic soils of the state of Pernambuco, Brazil; and the other in a greenhouse, after correction of the soils. As the test plant, the cowpea cultivar pele de moça, inoculated with Rhizobium strain BR3267 was used. The experiments were arranged in a randomised block design in a 2 x 5 factorial arrangement, two soils and five levels of the gypsum requirement (GR, equivalent to 50, 100, 150, 200 and 250% of the GR of the soil, as determined by the Schoonover M-1 method, with five replications. The following were evaluated: electrical conductivity of the soil saturation extract (EC, soil exchangeable sodium and percentage of soil exchangeable sodium (ESP, number of nodules (NN, nodule dry weight (NDW, shoot dry weight (SDW, shoot height (PH and nitrogen concentration (N in the shoots. Application of 100% of the GR, followed by the enough water for leaching, was effective for the correction of soil sodicity. The application of increasing levels of soil GR resulted in an increase in the number of nodules, dry weight of the nodules and shoots, and the height and levels of N absorbed by the plants in soil S2. In soil S1, the use of levels of 200 and 250% of soil the GR caused a decrease in all the variables under study.

  3. A dynamic model of soil salinity and drainage generation in irrigated agriculture: A framework for policy analysis

    Science.gov (United States)

    Dinar, Ariel; Aillery, Marcel P.; Moore, Michael R.

    1993-06-01

    This paper presents a dynamic model of irrigated agriculture that accounts for drainage generation and salinity accumulation. Critical model relationships involving crop production, soil salinity, and irrigation drainage are based on newly estimated functions derived from lysimeter field tests. The model allocates land and water inputs over time based on an intertemporal profit maximization objective function and soil salinity accumulation process. The model is applied to conditions in the San Joaquin Valley of California, where environmental degradation from irrigation drainage has become a policy issue. Findings indicate that in the absence of regulation, drainage volumes increase over time before reaching a steady state as increased quantities of water are allocated to leaching soil salts. The model is used to evaluate alternative drainage abatement scenarios involving drainage quotas and taxes, water supply quotas and taxes, and irrigation technology subsidies. In our example, direct drainage policies are more cost-effective in reducing drainage than policies operating indirectly through surface water use, although differences in cost efficiency are relatively small. In some cases, efforts to control drainage may result in increased soil salinity accumulation, with implications for long-term cropland productivity. While policy adjustments may alter the direction and duration of convergence to a steady state, findings suggest that a dynamic model specification may not be necessary due to rapid convergence to a comon steady state under selected scenarios.

  4. Spatial variability of soil salinity at different scales in the mangrove rice agro-ecosystem in West Africa.

    NARCIS (Netherlands)

    Sylla, M.; Stein, A.; Breemen, van N.; Fresco, L.O.

    1995-01-01

    Spatial variability of soil salinity in coastal low lands results from a complex interaction of climate, river hydrology, topography and tidal flooding. The aim of this study was to determine the significant effects of these causal factors at different scales in the West African mangrove

  5. Impacts of soil and groundwater salinization on tree crop performance in post-tsunami Aceh Barat, Indonesia

    Directory of Open Access Journals (Sweden)

    C. Marohn

    2012-09-01

    Full Text Available The Indian Ocean tsunami of December 2004 had far reaching consequences for agriculture in Aceh province, Indonesia, and particularly in Aceh Barat district, 150 km from the seaquake epicentre. In this study, the spatial distribution and temporal dynamics of soil and groundwater salinity and their impact on tree crops were monitored in Aceh Barat from 2006 to 2008. On 48 sampling points along ten transects, covering 40 km of coastline, soil and groundwater salinity were measured and related to mortality and yield depression of the locally most important tree crops. Given a yearly rainfall of over 3000 mm, initial groundwater salinity declined rapidly from over 10 to less than 2 mS cm−1 within two years. On the other hand, seasonal dynamics of the groundwater table in combination with intrusion of saline water into the groundwater body led to recurring elevated salinity, sufficient to affect crops. Tree mortality and yield depression in the flooded area varied considerably between tree species. Damage to coconut (65% trees damaged was related to tsunami run-up height, while rubber (50% trees damaged was mainly affected by groundwater salinity. Coconut yields (−35% in average were constrained by groundwater Ca2+ and Mg2+, while rubber yields (−65% on average were related to groundwater chloride, pH and soil sodium. These findings have implications on planting deep-rooted tree crops as growth will be constrained by ongoing oscillations of the groundwater table and salinity.

  6. Effects of NaCl and seawater induced salinity on survival and reproduction of three soil invertebrate species.

    Science.gov (United States)

    Pereira, C S; Lopes, I; Sousa, J P; Chelinho, S

    2015-09-01

    The increase of global mean temperature is raising serious concerns worldwide due to its potential negative effects such as droughts and melting of glaciers and ice caps leading to sea level rise. Expected impacts on soil compartment include floodings, seawater intrusions and use of saltwater for irrigation, with unknown effects on soil ecosystems and their inhabitants. The present study aimed at evaluating the effects of salinisation on soil ecosystems due to sea level rise. The reproduction and mortality of three standard soil invertebrate species (Folsomia candida, Enchytraeus crypticus, Hypoaspis aculeifer) in standard artificial OECD soil spiked with serial dilutions of seawater/gradient of NaCl were evaluated according to standard guidelines. An increased sensitivity was observed in the following order: H. aculeifer≪E. crypticus≈F. candida consistent with the different exposure pathways: springtails and enchytraeids are exposed by ingestion and contact while mites are mainly exposed by ingestion due to a continuous and thick exoskeleton. Although small differences were observed in the calculated effect electrical conductivity values, seawater and NaCl induced the same overall effects (with a difference in the enchytraeid tests where a higher sensitivity was found in relation to NaCl). The adverse effects described in the present study are observed on soils not considered saline. Therefore, the actual limit to define saline soils (4000 μS cm(-1)) does not reflect the existing knowledge when considering soil fauna. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Effects of Soil Salinity and Alkalinity on Grain Quality of Tolerant, Semi-Tolerant and Sensitive Rice Genotypes

    Directory of Open Access Journals (Sweden)

    P. SUREKHA RAO

    2013-07-01

    Full Text Available Soil salinity and alkalinity adversely affects the productivity and grain quality of rice. The grain quality of 19 rice genotypes characterized as salt tolerant (T, semi-tolerant (ST and sensitive (S was assessed in lysimeters containing saline and highly alkaline soils. Head rice recovery was reduced by salinity stress whereas it was not affected by alkalinity stress. The ratio of length to width (grain dimensions was significantly reduced in the T genotype even at low electrical conductivity (EC, 4 mS/cm and alkalinity (pH 9.5, whereas in the ST genotype, it was significantly reduced at high salinity (EC 8 mS/cm. There was no significant effect of any levels of salinity or alkalinity on grain dimensions in the S genotype. Amylose content was significantly reduced in T and ST groups even at low EC (4 mS/cm and alkalinity (pH 9.5 and the effect in the S genotype was only at high salinity. Starch content showed significant reduction at high salinity and alkalinity (EC 8 mS/cm and pH 9.8 in the T and ST genotypes and no significant effect was observed in the S genotype. The effect of both levels of salinity (EC 4 and 8 mS/cm and high alkalinity (pH 9.8 on gel consistency was observed only in the S genotype. The tolerant genotypes IR36 under high salinity, and CSR10 and CSR11 under alkali stress showed less reduction in amylose content. The T genotype BR4-10, and ST genotypes CSR30, CSR29 and CSR13 showed better gel consistency under saline and alkali stress. Amylose content was affected even at low salinity stress and thus important to be considered in breeding rice for salt tolerance. Overall, the grain quality of T and ST genotypes was less affected by saline and alkali stress compared to S ones.

  8. Earth Observation and Geospatial techniques for Soil Salinity and Land Capability Assessment over Sundarban Bay of Bengal Coast, India

    Science.gov (United States)

    Das, Sumanta; Choudhury, Malini Roy; Das, Subhasish; Nagarajan, M.

    2016-12-01

    To guarantee food security and job creation of small scale farmers to commercial farmers, unproductive farms in the South 24 PGS, West Bengal need land reform program to be restructured and evaluated for agricultural productivity. This study established a potential role of remote sensing and GIS for identification and mapping of salinity zone and spatial planning of agricultural land over the Basanti and Gosaba Islands(808.314sq. km) of South 24 PGS. District of West Bengal. The primary data i.e. soil pH, Electrical Conductivity (EC) and Sodium Absorption ratio (SAR) were obtained from soil samples of various GCP (Ground Control Points) locations collected at 50 mts. intervals by handheld GPS from 0-100 cm depths. The secondary information is acquired from the remotely sensed satellite data (LANDSAT ETM+) in different time scale and digital elevation model. The collected field samples were tested in the laboratory and were validated with Remote Sensing based digital indices analysisover the temporal satellite data to assess the potential changes due to over salinization. Soil physical properties such as texture, structure, depth and drainage condition is stored as attributes in a geographical soil database and linked with the soil map units. The thematic maps are integrated with climatic and terrain conditions of the area to produce land capability maps for paddy. Finally, The weighted overlay analysis was performed to assign theweights according to the importance of parameters taken into account for salineareaidentification and mapping to segregate higher, moderate, lower salinity zonesover the study area.

  9. Effects of Vinegar Bad and Flyash on the Growth of Sorghum and the Improvement of Saline Soils

    Directory of Open Access Journals (Sweden)

    FAN Na

    2017-10-01

    Full Text Available Based on the sorghum growth and salinity soil improvement, the effects of vinegar bad and flyash on the growth of sorghum and the improvement of saline soils were studied. The experiment was carried out with random block design, in 4 treatment, which were pure vinegar bad(treatment 1, vinegar bad and fly ash 1:1 ratio(treatment 2, vinegar bad and fly ash 2:1 ratio(treatment 3 and control respectively. The results showed that the contents of available nutrient in the four periods of sorghum growth increased firstly and then decreased, and the effect of vinegar bad and flyash treatment was better than that of control. Among them, the ratio 1:1 of vinegar and fly ash had the best effect. The results showed that compared with the control, the soil bulk density of treatment 1~3 was decreased by 19.6%, 28.6% and 11.32%, respectively. The spike length of treatment 1~3 was 6.25%, 9.06%, 3.93% higher than that of the control, respectively. The yield per plant of treatment 1~3 was increased by 10.53%, 13.26% and 8.89%, respectively. In summary, vinegar bad, flyash could improve the physical and chemical properties of saline soil, improve the environment of deep soil for plant growth, thereby increase the yield of sorghum.

  10. Accumulation and localization of sodium and potassium ions in maize plants on saline soil

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    S. N. Kabuzenko

    2013-02-01

    Full Text Available The goal of this work is studying the accumulation and distribution of Na+ and K+ in maize hybrids of different salt tolerance under conditions of the chloride salinity. The new corn hybrid Veselka MV (salt-tolerant and Odessa 375 MB (not salt-tolerant were studied. The plants grown in salt-free chernozem soil are control. In the experiment, sodium chloride was dissolved in the irrigation water to form the salinity of test soils up to concentrations of 0.25, 0.5, 0.75, and 1.0% of ovendry weight. Soil moisture in the pots was maintained at 60% of the full field water capacity, the air temperature was +25…+27 °C, and the light – 10 klux. Plant samples were dried in the oven under 70 °C. Then, the average sample of 10 specimens was thoroughly levigated in the porcelain pounder  and dispersed in distilled water at 100 °C. The ions were extracted, and the extracts were centrifuged for 20 min at 3000 rpm. The ions content in the cell sap was analysed. Plant samples (1 g were incubated 10 min in chloroform, dried carefully with filter paper, and then the cell sap was squeezed. 1 ml of clear top layer of the cell sap was dissolved in 10 ml of distilled water. Ions content was determined by the atomic absorption spectrophotometer ("Karl Zeiss", Germany. Salt-tolerant maize hybrid Veselka MW (14 days age is characterized by an increased content of Na+ in the root tissues in comparison with the above-ground parts. In Odessa 375 MB hybrid this regularity is less pronounced. With the increase of sodium chloride concentration in the soil the content of Na+ in the aerial parts of plants rises. That may be connected with the reduced role of a root barrier. The salt-tolerant hybrid has a higher content of Na+ in the roots as compared to the above-ground parts. The content of K+ was higher in the above-ground parts, which is more pronounced in the salt-tolerant hybrid Veselka MB. The decrease of K+ in cell sap of the root under saline conditions was

  11. Hyperspectral Remote Sensing for Detecting Soil Salinization Using ProSpecTIR-VS Aerial Imagery and Sensor Simulation

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    Odílio Coimbra da Rocha Neto

    2017-01-01

    Full Text Available Soil salinization due to irrigation affects agricultural productivity in the semi-arid region of Brazil. In this study, the performance of four computational models to estimate electrical conductivity (EC (soil salinization was evaluated using laboratory reflectance spectroscopy. To investigate the influence of bandwidth and band positioning on the EC estimates, we simulated the spectral resolution of two hyperspectral sensors (airborne ProSpecTIR-VS and orbital Hyperspectral Infrared Imager (HyspIRI and three multispectral instruments (RapidEye/REIS, High Resolution Geometric (HRG/SPOT-5, and Operational Land Imager (OLI/Landsat-8. Principal component analysis (PCA and the first-order derivative analysis were applied to the data to generate metrics associated with soil brightness and spectral features, respectively. The three sets of data (reflectance, PCA, and derivative were tested as input variable for Extreme Learning Machine (ELM, Ordinary Least Square regression (OLS, Partial Least Squares Regression (PLSR, and Multilayer Perceptron (MLP. Finally, the laboratory models were inverted to a ProSpecTIR-VS image (400–2500 nm acquired with 1-m spatial resolution in the northeast of Brazil. The objective was to estimate EC over exposed soils detected using the Normalized Difference Vegetation Index (NDVI. The results showed that the predictive ability of the linear models and ELM was better than that of the MLP, as indicated by higher values of the coefficient of determination (R2 and ratio of the performance to deviation (RPD, and lower values of the root mean square error (RMSE. Metrics associated with soil brightness (reflectance and PCA scores were more efficient in detecting changes in the EC produced by soil salinization than metrics related to spectral features (derivative. When applied to the image, the PLSR model with reflectance had an RMSE of 1.22 dS·m−1 and an RPD of 2.21, and was more suitable for detecting salinization (10

  12. Measurement of terrestrial radiation for assessment of gamma dose from cultivated and barren saline soils of Faisalabad in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Tufail, M. [Pakistan Institute of Engineering and Applied Sciences, P.O. Nilore, Islamabad (Pakistan)]. E-mail: dr_mtufail@yahoo.com; Akhtar, Nasim [Health Physics Division, NIAB, Jhang Road, Faisalabad (Pakistan); Waqas, M. [Department of Earth Sciences, Quad-i-Azam University, Islamabad (Pakistan)

    2006-04-15

    Natural radioactivity originates from extraterrestrial sources as well as from primordial radioactive elements in the earth crust. The amount of radioactivity in soil varies widely and is a source of continuous exposure of human beings to terrestrial radioactivity that depends upon the type of soil and its uses. For the investigation of radioactivity in barren and cultivated soil, an area of about 80ha of saline soil was selected in Pakka Anna near the city of Faisalabad in the Punjab province of Pakistan. Activity concentration levels due to {sup 40}K, {sup 137}Cs, {sup 226}Ra and {sup 232}Th were measured with HPGe detector in 250 saline soil samples collected at a spacing of about 8ha at a depth of 0-25cm with intervals of 5cm depth. Activity concentration ranges of the concerned radionuclides for both of the soils were as follows: {sup 40}K, for barren and cultivated saline soil was 499-604 and 563-629Bqkg{sup -1}, respectively; {sup 137}Cs, 3.57-3.63 and 1.98-5.15Bqkg{sup -1}; {sup 226}Ra, 24-29 and 27-33Bqkg{sup -1}, and {sup 232}Th, 49-54 and 46-62Bqkg{sup -1}. Gamma dose was estimated using the activity to dose rate conversion factors. The measured activity concentrations and the estimated radiation dose were found to be lying within the range specified in the 2000 report of UNSCEAR. Chemical analysis for Na, Ca and Mg was also carried out along with the measurement of electrical conductivity and pH of soil samples.

  13. Avoidance behaviour of two eco-physiologically different earthworms (Eisenia fetida and Aporrectodea caliginosa) in natural and artificial saline soils.

    Science.gov (United States)

    Owojori, O J; Reinecke, A J

    2009-04-01

    We studied the avoidance behaviour of Eisenia fetida and Aporrectodea caliginosa in OECD artificial soil spiked with NaCl and in natural saline soil (of varying ionic constitutions) collected from Robertson Experimental Farm (ROBS) in Western Cape, South Africa. For each organism, the ecotoxicological test was performed using a two-chamber test over a period of 48 h. The results showed that in the OECD soil, the avoidance EC50 (the concentration/electrical conductivity at which there is effect on 50% of the organisms) for A. caliginosa of 667 mg kg(-1) NaCl was lower than 1164 mg kg(-1) for E. fetida. Similarly in ROBS soil, the avoidance EC50 for A. caliginosa of 0.26 dS m(-1) was lower than 0.56 dS m(-1) in E. fetida. These results indicated that A. caliginosa showed better avoidance to salinity than E. fetida irrespective of soil types or ionic constitution. When compared with literature data, EC50 values in avoidance tests were either lower or comparable to those of reproduction, which was the most sensitive life-cycle parameter. The only exception was the EC50 value for avoidance of E. fetida in natural soil which was higher than for reproduction suggesting that the predictive value of the avoidance test for this species might be lower in natural soils. The variation in sensitivities of these earthworms could be as a result of differences in their eco-physiology. These findings suggest the relevance of the avoidance test as a suitable screening method showing first tendencies of saline stress on the habitat function of soils.

  14. Effect of different levels of sulfur on the productivity of wheat in a saline sodic soil

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    Arshad Ali, Muhammad Arshadullah, Syed Ishtiaq Hyder and Imdad Ali Mahmood

    2012-05-01

    Full Text Available A field experiment was carried out to evaluate the effect of different S levels ( 0, 25, 50 and 75 kg S ha-1 on growth and ionic concentration of wheat variety (Inqlab-91 directly sown in a saline sodic soil (ECe=4.92 dS m-1, pH=8.22 and SAR=16.15 dS m-1 at Zaidi Farm, Sheikhupura during winter 2009. Treatments were arranged using randomized complete block design (RCBD with three replications. The crop was harvested at maturity, data on tillering, plant height, spike length, number of grains spike-1, 1000- grain weight, straw and wheat grain yields were recorded. Na, K, Ca and Mg concentration in grain and straw were estimated using atomic absorption spectroscopy. Tillering, number of grains spike-1, 1000- grain weight, grain yield significantly (p≤ 0.05 increased by enhancing the rate of S application. Wheat grain yield was the maximum (4040 kg ha-1 at the application of 50 kg S ha-1 and 26% more than control treatment. The maximum number of tillers / 5 plants (110, number of grains spike-1 (63.6 and 1000 grain weight (47 g were recorded with S application at 50 kg ha-1. Positive correlations (r= 0.91 and (r=0.79 between calcium and potassium contents in grain and wheat grain yield. However negative correlation (-0.88 between Na content in grain and wheat grain yield was found. It indicates presence of significantly higher Ca and K contents in grains receiving S application help plants to attain more Ca and K to avoid sodium uptake which has been an added advantage to alleviate salinity/sodicity. However, economical analysis showed that maximum value cost ratio (3.52:1 was found where 25 kg ha-1 S was applied.

  15. Soil water retention at varying matric potentials following repeated wetting with modestly saline-sodic water and subsequent air drying

    Energy Technology Data Exchange (ETDEWEB)

    Browning, L.S.; Hershberger, K.R.; Bauder, J.W. [Montana State University, Bozeman, MT (United States). Dept. of Land Resources & Environmental Science

    2007-07-01

    Coal bed natural gas (CBNG) development in the Powder River (PR) Basin produces modestly saline, highly sodic wastewater. This study assessed impacts of wetting four textural groups (0-11%, 12-22%, 23 -33%, and > 33% clay (g clay/100 g soil) x 100%))with simulated PR or CBNG water on water retention. Soils received the following treatments with each water quality: a single wetting event, five wetting and drying events, or five wetting and drying events followed by leaching with salt-free water. Treated samples were then resaturated with the final treatment water and equilibrated to -10, -33, -100, -500, or -1,500 kPa. At all potentials, soil water retention increased significantly with increasing clay content. Drought-prone soils lost water-holding capacity between saturation and field capacity with repeated wetting and drying, whereas finer textured soils withstood this treatment better and had increased water-retention capacity at lower matric potentials.

  16. Soil- and plant- water uptake in saline environments and their consequences to plant adaptation in fluctuating climates

    Science.gov (United States)

    Volpe, V.; Albertson, J. D.; Katul, G. G.; Marani, M.

    2010-12-01

    Ecological processes determining plant colonization are quite peculiar and competition among different species is governed by a set of unique adaptations to stress conditions caused by drought, hypoxic or hyper-saline conditions. These adaptations and possible positive feedbacks often lead to the formation of patterns of vegetation colonization and spatial heterogeneity (zonation), and play a primary role in the stabilization of sediments. It is these issues that frame the scope of this study. The main objective of this work is to track one of the fundamental pathways between plant adaptation (quantified in terms of physiological and ecological attributes such as leaf area or root density profile) and feedbacks (quantified by plant-mediated alterations to water availability and salinity levels): root water uptake. Because root-water uptake is the main conduit connecting transpiring leaves to reservoirs of soil water, the means by which salinity modifies the processes governing its two end-points and any two-way interactions between them serves as a logical starting point. Salinity effects on leaf transpiration and photosynthesis are first explored via stomatal optimization principles that maximize carbon gain at a given water loss for autonomous leaves. Salinity directly affects leaf physiological attributes such as mesophyll conductance and photosynthetic parameters and hence over-all conductance to transpiration as well as different strategies to cope with the high salinity (e.g. through salt seclusion, compartmentation and osmotic adjustments). A coupled model of subsurface flow based on a modified Richards’ equation that accounts for the effects of increasing salinity, anaerobic conditions, water stress and compensation factors is developed. Plant water uptake is considered as a soil moisture sink term with a potential rate dictated by the carbon demands of the leaves, and an actual rate that accounts for both - hydraulic and salinity limitations. Using this

  17. Coupled Electrokinetics-Adsorption Technique for Simultaneous Removal of Heavy Metals and Organics from Saline-Sodic Soil

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    Salihu Lukman

    2013-01-01

    Full Text Available In situ remediation technologies for contaminated soils are faced with significant technical challenges when the contaminated soil has low permeability. Popular traditional technologies are rendered ineffective due to the difficulty encountered in accessing the contaminants as well as when employed in settings where the soil contains mixed contaminants such as petroleum hydrocarbons, heavy metals, and polar organics. In this study, an integrated in situ remediation technique that couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg, was used in this study to investigate the efficiency of contaminant removal. For the 21-day period of continuous electrokinetics-adsorption experimental run, efficiency for the removal of Zn, Pb, Cu, Cd, Cr, Hg, phenol, and kerosene was found to reach 26.8, 55.8, 41.0, 34.4, 75.9, 92.49, 100.0, and 49.8%, respectively. The results obtained suggest that integrating adsorption into electrokinetic technology is a promising solution for removal of contaminant mixture from saline-sodic soils.

  18. Coupled electrokinetics-adsorption technique for simultaneous removal of heavy metals and organics from saline-sodic soil.

    Science.gov (United States)

    Lukman, Salihu; Essa, Mohammed Hussain; Mu'azu, Nuhu Dalhat; Bukhari, Alaadin

    2013-01-01

    In situ remediation technologies for contaminated soils are faced with significant technical challenges when the contaminated soil has low permeability. Popular traditional technologies are rendered ineffective due to the difficulty encountered in accessing the contaminants as well as when employed in settings where the soil contains mixed contaminants such as petroleum hydrocarbons, heavy metals, and polar organics. In this study, an integrated in situ remediation technique that couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg), was used in this study to investigate the efficiency of contaminant removal. For the 21-day period of continuous electrokinetics-adsorption experimental run, efficiency for the removal of Zn, Pb, Cu, Cd, Cr, Hg, phenol, and kerosene was found to reach 26.8, 55.8, 41.0, 34.4, 75.9, 92.49, 100.0, and 49.8%, respectively. The results obtained suggest that integrating adsorption into electrokinetic technology is a promising solution for removal of contaminant mixture from saline-sodic soils.

  19. Utilization of organic fertilizer to increase paddy growth and productivity using System of Rice Intensification (SRI method in saline soil

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    V . O . Subardja

    2016-01-01

    Full Text Available Soil salinity has negative effect on soil biodiversity as well as microbial activities. Hence, rice growth also effected by salinity. Application of organic fertilizer and adoption of System of Rice Intensification (SRI cultivation might improve the (biological soil properties and increase rice yield. The aim of this study was to evaluate the effect of two different rice cultivation methods namely conventional rice cultivation method and System of Rice Intensification (SRI rice cultivation method and two kinds organic fertilizer on improvement of soil biological properties and rice yield. In this study, a split plot experimental design was applied where rice cultivation method (conventional and SRI was the main plot and two kinds of organic fertilizer (market waste and rice straw was the sub plot. The treatments had four replicates. The results showed that SRI cultivation with market waste organic fertilizer could increase soil biological properties (population of microbe, fungi and soil respiration. The same treatment also increased rice growth and production. Combination of SRI and market waste organic fertilizer yielded the highest rice production (7.21 t/ha.

  20. Simulated storm surge effects on freshwater coastal wetland soil porewater salinity and extractable ammonium levels: Implications for marsh recovery after storm surge

    Science.gov (United States)

    McKee, M.; White, J. R.; Putnam-Duhon, L. A.

    2016-11-01

    Coastal wetland systems experience both short-term changes in salinity, such as those caused by wind-driven tides and storm surge, and long-term shifts caused by sea level rise. Salinity increases associated with storm surge are known to have significant effects on soil porewater chemistry, but there is little research on the effect of flooding length on salt penetration depth into coastal marsh soils. A simulated storm surge was imposed on intact soil columns collected from a non-vegetated mudflat and a vegetated marsh site in the Wax Lake Delta, LA. Triplicate intact cores were continuously exposed to a 35 salinity water column (practical salinity scale) for 1, 2, and 4 weeks and destructively sampled in order to measure porewater salinity and extractable NH4sbnd N at two cm depth intervals. Salinity was significantly higher in the top 8 cm for both the marsh and mudflat cores after one week of flooding. After four weeks of flooding, salinity was significantly higher in marsh and mudflat cores compared to the control (no salinity) cores throughout the profile for both sites. Extractable ammonium levels increased significantly in the marsh cores throughout the experiment, but there was only a marginally (p < 0.1) significant increase seen in the mudflat cores. Results indicate that porewater salinity levels can become significantly elevated within a coastal marsh soil in just one week. This vertical intrusion of salt can potentially negatively impact macrophytes and associated microbial communities for significantly longer term post-storm surge.

  1. Study of hydro-saline characteristics of soils a palm grove in basin of Ouargla (Northern Algerian Sahara)

    Science.gov (United States)

    Rezagui, D.; Bouhoun, M. Daddi; Boutoutaou, D.; Djaghoubi, A.

    2016-07-01

    Saharan soils are often faced with several problems of development, taking account the hydro-edaphic constraints, mainly of hydric types by water table, mechanical by gypso-calcareous crusts and saline by irrigation waters and upwelling of water table. Our work consists in doing a soil characterization of a palm grove in Ouargla in order to study the constraints hydro-halomorphes. The results show that irrigation water by two plies of Senonian and Mioplcène had a high salinity with a value of 2.83 and 5.10 dS.m-1 respectively. The conduct of irrigation is traditional random of submersion type. The palm grove has a poor drainage with a level of water table 156.67±15.71 cm and salinity of 31.37±34.04 dS.m-1. The drains are open type and their maintenance is not regular. This situation of management of irrigation-drainage promotes the upwelling of water table and the waterlogging in soils. The study of soil profiles shows the existence of mechanical obstruction of gypso-calcareous crusts which limit the entrenchment of the date palms and the leaching of salts. Soil salinity is excessive in profiles with a range of 8.98 ± 4.58 dS.m-1. This accumulation of salts is due to the dynamic ascending and descending of salts respectively under the effect of upwelling of water table and leaching by irrigation. The salinization, the upwelling of water table and the presence of gypso-calcareous crusts recorded in Ouargla testify to a degradation hydro-halomorphe and mechanic of soil which constitute the major constraints in the management of system irrigation-drainage and sustainable agricultural development of the palm groves of the basin of Ouargla. Some hydro-agricultural planning are necessary to apply in the oasis to improve the hydro-mechanical properties of soils in order to reduce their degradation.

  2. Brevibacterium album sp. nov., a novel actinobacterium isolated from a saline soil in China.

    Science.gov (United States)

    Tang, Shu-Kun; Wang, Yun; Schumann, Peter; Stackebrandt, Erko; Lou, Kai; Jiang, Cheng-Lin; Xu, Li-Hua; Li, Wen-Jun

    2008-03-01

    A novel Gram-positive, rod-shaped actinobacterium, designated strain YIM 90718(T), was isolated from a saline soil in Xinjiang province, north-west China, and subjected to polyphasic taxonomy. The peptidoglycan type was A1gamma and the cell-wall sugars contained galactose. Phospholipids were phosphatidylglycerol and diphosphatidylglycerol. The predominant menaquinone was MK-8(H(2)). The major fatty acids were anteiso-C(15 : 0), anteiso-C(17 : 0) and iso-C(15 : 0). All of these chemotaxonomic data assigned the new isolate YIM 90718(T) consistently to the genus Brevibacterium. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM 90718(T) formed a distinct phyletic lineage in the genus Brevibacterium and showed the highest sequence similarity (96.2 %) to Brevibacterium samyangense SST-8(T) and low similarity (Brevibacterium. On the based of the polyphasic evidence, a novel species, Brevibacterium album sp. nov., is proposed, with the type strain YIM 90718(T) (=DSM 18261(T) =KCTC 19173(T) =CCTCC AB 206112(T)).

  3. Identification and characterization of a novel trehalose synthase gene derived from saline-alkali soil metagenomes.

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    Ling Jiang

    Full Text Available A novel trehalose synthase (TreS gene was identified from a metagenomic library of saline-alkali soil by a simple activity-based screening system. Sequence analysis revealed that TreS encodes a protein of 552 amino acids, with a deduced molecular weight of 63.3 kDa. After being overexpressed in Escherichia coli and purified, the enzymatic properties of TreS were investigated. The recombinant TreS displayed its optimal activity at pH 9.0 and 45 °C, and the addition of most common metal ions (1 or 30 mM had no inhibition effect on the enzymatic activity evidently, except for the divalent metal ions Zn(2+ and Hg(2+. Kinetic analysis showed that the recombinant TreS had a 4.1-fold higher catalytic efficiency (Kcat/K m for maltose than for trehalose. The maximum conversion rate of maltose into trehalose by the TreS was reached more than 78% at a relatively high maltose concentration (30%, making it a good candidate in the large-scale production of trehalsoe after further study. In addition, five amino acid residues, His172, Asp201, Glu251, His318 and Asp319, were shown to be conserved in the TreS, which were also important for glycosyl hydrolase family 13 enzyme catalysis.

  4. The influence of soil salinity on volatile organic compounds emission and photosynthetic parameters of Solanum lycopersicum L. varieties

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    Tomescu Daniel

    2017-05-01

    Full Text Available Soil salinity is one of the best known stress factors of plants that can lead to crop yield reduction. Therefore, it is important to identify new tolerance varieties of plants that can grow on saline soils. We have studied the influence of salt on five different tomato varieties from the Western region of Romania and compared them with a commercial hybrid and found that one of them (Rudna is a very salt-tolerant variety (up to 200 mM NaCl. The assimilation rates and stomata conductance of water vapour are affected by salinity but some of the local varieties of tomato exhibit quite good tolerance. We found that all plants under salinity stress emit (Z-3-hexenol (a C6, green leaf volatile and the emission of all terpenes increased in proportion to the salt concentration. The emission of three terpenes, (Z-beta-ocimene. 2-carene and beta-phellandrene, have been quantitatively correlated with salt concentration.

  5. Studies on non-symbiotic diazotrophic bacterial populations of coastal arable saline soils of India.

    Science.gov (United States)

    Barua, Shilajit; Tripathi, Sudipta; Chakraborty, Ashis; Ghosh, Sagarmoy; Chakrabarti, Kalyan

    2011-07-01

    The effect of fluctuations of salinity in three different seasons on diazotrophic populations and N(2) fixation in six mono cropped rice field soils of the coastal region of the Gangetic delta of West Bengal, India, was studied. The average pH, ECe, organic carbon and total nitrogen of the soils ranged from 4.99-7.08, 2.02-19.58 dSm(-1), 4.68-12.03 g kg(-1) and 0.44-1.70 g kg (-1), respectively. The average log colony forming units of the bacterial populations and N(2)-fixation in the soils varied from 4.61 to 5.86 and 2.74 to 4.52 mg N(2) fixed 50 ml (-1) culture media respectively, with the lowest value recorded in summer. Recovery of microorganisms and N(2)- fixation gradually decreased with extraneous addition of NaCl in the culture media. All the eight isolates were Gram positive, spore and capsule formers. They could utilize glucose, sucrose, mannitol, starch, citrate and nitrate, and were catalase and gelatinase positive, but indole, methyl red and Vogues Proskauer reaction negative. The organisms produced alkaline reaction on TSI agar slant. The acetylene reduction assay of the isolates at 0 and 1% NaCl in the culture media were 4.51-164.52 and 1.72-100.6 nmole C(2)H(4) ml(-1) culture media in 72 h, respectively. The isolates could fix 2.42-4.45 and 2.04-4.08 mg N(2) fixed 50 ml(-1) culture media at 0 and 1% NaCl in the culture media respectively. 16S rDNA sequences of the isolates were similar to the species: Bacillus sp. isolate 28A, Bacillus sp. MOLA 87, Bacillus sp. By113 (B)Ydz-dh, Bacillus sp. PN13, Bacillus licheniformis strain RH101, Bacterium Antarctica 14, Bacillus sp. PN13 and Bacillus megaterium.

  6. Bacteria in combination with fertilizers promote root and shoot growth of maize in saline-sodic soil

    Directory of Open Access Journals (Sweden)

    Muhammad Zafar-ul-Hye

    2015-03-01

    Full Text Available Salinity is the leading abiotic stress hampering maize (Zea maysL. growth throughout the world, especially in Pakistan. During salinity stress, the endogenous ethylene level in plants increases, which retards proper root growth and consequent shoot growth of the plants. However, certain bacteria contain the enzyme 1-aminocyclopropane-1-carboxylate (ACC deaminase, which converts 1-aminocyclopropane-1-carboxylic acid (an immediate precursor of ethylene biosynthesis in higher plants into ammonia and α-ketobutyrate instead of ethylene. In the present study, two Pseudomonas bacterial strains containing ACC-deaminase were tested separately and in combinations with mineral fertilizers to determine their potential to minimize/undo the effects of salinity on maize plants grown under saline-sodic field conditions. The data recorded at 30, 50 and 70 days after sowing revealed that both the Pseudomonas bacterial strains improved root and shoot length, root and shoot fresh weight, and root and shoot dry weight up to 34, 43, 35, 71, 55 and 68%, respectively, when applied without chemical fertilizers: these parameter were enhanced up to 108, 95, 100, 131, 100 and 198%, respectively, when the strains were applied along with chemical fertilizers. It can be concluded that ACC-deaminase Pseudomonas bacterial strains applied alone and in conjunction with mineral fertilizers improved the root and shoot growth of maize seedlings grown in saline-sodic soil.

  7. Bacteria in combination with fertilizers promote root and shoot growth of maize in saline-sodic soil.

    Science.gov (United States)

    Zafar-Ul-Hye, Muhammad; Farooq, Hafiz Muhammad; Hussain, Mubshar

    2015-03-01

    Salinity is the leading abiotic stress hampering maize ( Zea mays L.) growth throughout the world, especially in Pakistan. During salinity stress, the endogenous ethylene level in plants increases, which retards proper root growth and consequent shoot growth of the plants. However, certain bacteria contain the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which converts 1-aminocyclopropane-1-carboxylic acid (an immediate precursor of ethylene biosynthesis in higher plants) into ammonia and α-ketobutyrate instead of ethylene. In the present study, two Pseudomonas bacterial strains containing ACC-deaminase were tested separately and in combinations with mineral fertilizers to determine their potential to minimize/undo the effects of salinity on maize plants grown under saline-sodic field conditions. The data recorded at 30, 50 and 70 days after sowing revealed that both the Pseudomonas bacterial strains improved root and shoot length, root and shoot fresh weight, and root and shoot dry weight up to 34, 43, 35, 71, 55 and 68%, respectively, when applied without chemical fertilizers: these parameter were enhanced up to 108, 95, 100, 131, 100 and 198%, respectively, when the strains were applied along with chemical fertilizers. It can be concluded that ACC-deaminase Pseudomonas bacterial strains applied alone and in conjunction with mineral fertilizers improved the root and shoot growth of maize seedlings grown in saline-sodic soil.

  8. Intraspecific variation in growth of marsh macrophytes in response to salinity and soil type: Implications for wetland restoration

    Science.gov (United States)

    Howard, R.J.

    2010-01-01

    Genetic diversity within plant populations can influence plant community structure along environmental gradients. In wetland habitats, salinity and soil type are factors that can vary along gradients and therefore affect plant growth. To test for intraspecific growth variation in response to these factors, a greenhouse study was conducted using common plants that occur in northern Gulf of Mexico brackish and salt marshes. Individual plants of Distichlis spicata, Phragmites australis, Schoenoplectus californicus, and Schoenoplectus robustus were collected from several locations along the coast in Louisiana, USA. Plant identity, based on collection location, was used as a measure of intraspecific variability. Prepared soil mixtures were organic, silt, or clay, and salinity treatments were 0 or 18 psu. Significant intraspecific variation in stem number, total stem height, or biomass was found in all species. Within species, response to soil type varied, but increased salinity significantly decreased growth in all individuals. Findings indicate that inclusion of multiple genets within species is an important consideration for marsh restoration projects that include vegetation plantings. This strategy will facilitate establishment of plant communities that have the flexibility to adapt to changing environmental conditions and, therefore, are capable of persisting over time. ?? Coastal and Estuarine Research Federation 2009.

  9. Application of organic amendments to a coastal saline soil in north China: effects on soil physical and chemical properties and tree growth.

    Directory of Open Access Journals (Sweden)

    Linlin Wang

    Full Text Available The ability of the following four organic amendments to ameliorate saline soil in coastal northern China was investigated from April 2010 to October 2012 in a field experiment: green waste compost (GWC, sedge peat (SP, furfural residue (FR, and a mixture of GWC, SP and FR (1∶1∶1 by volume (GSF. Compared to a non-amended control (CK, the amendments, which were applied at 4.5 kg organic matter m(-3, dramatically promoted plant growth; improved soil structure; increased the cation exchange capacity (CEC, organic carbon, and available nutrients; and reduced the salt content, electrical conductivity (EC, and exchangeable sodium percentage (ESP. At the end of the experiment in soil amended with GSF, bulk density, EC, and ESP had decreased by 11, 87, and 71%, respectively, and total porosity and organic carbon had increased by 25 and 96% respectively, relative to the CK. The GSF treatment resulted in a significantly lower Na(++K(+ content than the other treatments. CEC and the contents of available N, P, and K were significantly higher in the GSF-treated soil than in the CK and were the highest in all treatments. The FR treatment resulted in the lowest pH value and Ca(2+ concentration, which decreased by 8% and 39%, respectively, relative to the CK. Overall, the results indicate that a combination of green waste compost, sedge peat and furfural residue (GSF treatment has substantial potential for ameliorating saline soils in the coastal areas of northern China, and it works better than each amendment alone. Utilization of GWC and FR can be an alternative organic amendment to substitute the nonrenewable SP in saline soil amelioration.

  10. Application of organic amendments to a coastal saline soil in north China: effects on soil physical and chemical properties and tree growth.

    Science.gov (United States)

    Wang, Linlin; Sun, Xiangyang; Li, Suyan; Zhang, Tao; Zhang, Wei; Zhai, Penghui

    2014-01-01

    The ability of the following four organic amendments to ameliorate saline soil in coastal northern China was investigated from April 2010 to October 2012 in a field experiment: green waste compost (GWC), sedge peat (SP), furfural residue (FR), and a mixture of GWC, SP and FR (1∶1∶1 by volume) (GSF). Compared to a non-amended control (CK), the amendments, which were applied at 4.5 kg organic matter m(-3), dramatically promoted plant growth; improved soil structure; increased the cation exchange capacity (CEC), organic carbon, and available nutrients; and reduced the salt content, electrical conductivity (EC), and exchangeable sodium percentage (ESP). At the end of the experiment in soil amended with GSF, bulk density, EC, and ESP had decreased by 11, 87, and 71%, respectively, and total porosity and organic carbon had increased by 25 and 96% respectively, relative to the CK. The GSF treatment resulted in a significantly lower Na(+)+K(+) content than the other treatments. CEC and the contents of available N, P, and K were significantly higher in the GSF-treated soil than in the CK and were the highest in all treatments. The FR treatment resulted in the lowest pH value and Ca(2+) concentration, which decreased by 8% and 39%, respectively, relative to the CK. Overall, the results indicate that a combination of green waste compost, sedge peat and furfural residue (GSF treatment) has substantial potential for ameliorating saline soils in the coastal areas of northern China, and it works better than each amendment alone. Utilization of GWC and FR can be an alternative organic amendment to substitute the nonrenewable SP in saline soil amelioration.

  11. Salinity stress accelerates the effect of cadmium toxicity on soil N dynamics and cycling: Does joint effect of these stresses matter?

    Science.gov (United States)

    Raiesi, Fayez; Razmkhah, Mahshid; Kiani, Shahram

    2018-02-07

    The objective of this study was to determine responses of soil nitrogen (N) transformation, microbial biomass N, and urease activity to the combined effect of cadmium (Cd) toxicity (0 and 30 mg kg -1 ) and NaCl stress (0, 7.5 and 15 dS m -1 ) in a clay loam soil unamended (0%) or amended with alfalfa residues (1%, w/w). Cd, NaCl, and alfalfa residues were added to the soil, and the mixtures were incubated for 90 days under standard laboratory conditions (25 ± 1 °C and 70% of water holding capacity [WHC]). The results showed that salinity increased soil Cd availability and toxicity and subsequently decreased soil microbial N transformations (i.e., potential ammonification and nitrification as well as net N mineralization), arginine ammonification and nitrification rates, microbial biomass N, and urease activity. The adverse effects of salinity on soil microbial properties were greater in Cd-polluted than unpolluted soils, at high than low salinity levels, but were lower in residue-amended than unamended soils. These effects were mainly attributed to the increased Cd availability under saline conditions or the decreased Cd availability with residue addition. All the measured soil microbial attributes showed a negative correlation with the available Cd content in the soil. The interaction or combined effects of Cd and NaCl on soil microbial attributes were mostly synergistic in residue-unamended soils but antagonistic in residue-amended soils. The addition of organic residues to Cd-polluted soils may moderate salinity effect, and thus could stimulate the activity of ammonifiers and nitrifiers, as well as urease. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Invasion Potential of Two Tropical Physalis Species in Arid and Semi-Arid Climates: Effect of Water-Salinity Stress and Soil Types on Growth and Fecundity.

    Science.gov (United States)

    Ozaslan, Cumali; Farooq, Shahid; Onen, Huseyin; Bukun, Bekir; Ozcan, Selcuk; Gunal, Hikmet

    2016-01-01

    Invasive plants are recognized for their impressive abilities to withstand adverse environmental conditions however, all invaders do not express the similar abilities. Therefore, survival, growth, nutrient uptake and fecundity of two co-occurring, invasive Physalis species were tested under water and salinity stresses, and different soil textures in the current study. Five different water stress levels (100, 75, 50, 25, and 12.5% pot water contents), four different soil salinity levels (0, 3, 6, and 12 dSm-1) and four different soil textures (67% clay, 50% clay, silt clay loam and sandy loam) were included in three different pot experiments. Both weeds survived under all levels of water stress except 12.5% water contents and on all soil types however, behaved differently under increasing salinity. The weeds responded similarly to salinity up till 3 dSm-1 whereas, P. philadelphica survived for longer time than P. angulata under remaining salinity regimes. Water and salinity stress hampered the growth and fecundity of both weeds while, soil textures had slight effect. Both weeds preferred clay textured soils for better growth and nutrient uptake however, interactive effect of weeds and soil textures was non-significant. P. angulata accumulated higher K and Na while P. philadelphica accrued more Ca and Mg as well as maintained better K/Na ratio. P. angulata accumulated more Na and P under salinity stress while, P. philadelphica accrued higher K and Mg, and maintained higher K/Na ratio. Collectively, highest nutrient accumulation was observed under stress free conditions and on clay textured soils. P. philadelphica exhibited higher reproductive output under all experimental conditions than P. angulata. It is predicted that P. philadelphica will be more problematic under optimal water supply and high salinity while P. angulata can better adapt water limited environments. The results indicate that both weeds have considerable potential to further expand their ranges in

  13. Invasion Potential of Two Tropical Physalis Species in Arid and Semi-Arid Climates: Effect of Water-Salinity Stress and Soil Types on Growth and Fecundity.

    Directory of Open Access Journals (Sweden)

    Cumali Ozaslan

    Full Text Available Invasive plants are recognized for their impressive abilities to withstand adverse environmental conditions however, all invaders do not express the similar abilities. Therefore, survival, growth, nutrient uptake and fecundity of two co-occurring, invasive Physalis species were tested under water and salinity stresses, and different soil textures in the current study. Five different water stress levels (100, 75, 50, 25, and 12.5% pot water contents, four different soil salinity levels (0, 3, 6, and 12 dSm-1 and four different soil textures (67% clay, 50% clay, silt clay loam and sandy loam were included in three different pot experiments. Both weeds survived under all levels of water stress except 12.5% water contents and on all soil types however, behaved differently under increasing salinity. The weeds responded similarly to salinity up till 3 dSm-1 whereas, P. philadelphica survived for longer time than P. angulata under remaining salinity regimes. Water and salinity stress hampered the growth and fecundity of both weeds while, soil textures had slight effect. Both weeds preferred clay textured soils for better growth and nutrient uptake however, interactive effect of weeds and soil textures was non-significant. P. angulata accumulated higher K and Na while P. philadelphica accrued more Ca and Mg as well as maintained better K/Na ratio. P. angulata accumulated more Na and P under salinity stress while, P. philadelphica accrued higher K and Mg, and maintained higher K/Na ratio. Collectively, highest nutrient accumulation was observed under stress free conditions and on clay textured soils. P. philadelphica exhibited higher reproductive output under all experimental conditions than P. angulata. It is predicted that P. philadelphica will be more problematic under optimal water supply and high salinity while P. angulata can better adapt water limited environments. The results indicate that both weeds have considerable potential to further expand

  14. A natural saline soil as a model for understanding to what extent the concentration of salt affects the distribution of microorganisms

    Science.gov (United States)

    Canfora, Loredana; Pinzari, Flavia; Lo Papa, Giuseppe; Vittori Antisari, Livia; Vendramin, Elisa; Salvati, Luca; Dazzi, Carmelo; Benedetti, Anna

    2017-04-01

    Soils preserve and sustain life. Their health and functioning are crucial for crop production and for the maintenance of major ecosystem services. Human induced salinity is one of the main soil threats that reduces soil fertility and affect crop yields. In recent times, great attention has been paid to the general shortage of arable land and to the increasing demand for ecological restoration of areas affected by salinization processes. Despite the diffuse interest on the effects of salinization on plants' growth, and all the derived socioeconomic issues, very few studies analyzed the ecology of the microbial species in naturally saline soils and the resilience of biological fertility in these extreme habitats. Microorganisms inhabiting such environments may share a strategy, may have developed multiple adaptations for maintaining their populations, and cope eventually to extreme conditions by altruistic or cooperative behaviors for maintaining their metabolism active. The understanding and the knowledge of the composition and distribution of microbial communities in natural hypersaline soils can be interesting for ecological reasons but also to develop new restoration strategy where soil fertility was compromised by natural accidents or human mismanagement. The aim of this research was to provide specific information on saline soils in Italy, stressing mainly their distribution, the socioeconomic issues and the understanding of the characterizing ecological processes. Moreover, natural saline soils were used as a model for understanding to what extent the concentration of salt can affect some basic microbial processes. In the present study, physical, chemical and microbiological soil properties were investigated in the shallower horizons of natural salt affected soils in Sicily (Italy), where some ecological contrasting variables acted as strong drivers in fungal and bacterial spatial distribution. Furthermore, the interface between biological and geochemical

  15. Earth Observation and Geospatial techniques for Soil Salinity and Land Capability Assessment over Sundarban Bay of Bengal Coast, India

    Directory of Open Access Journals (Sweden)

    Das Sumanta

    2016-12-01

    Full Text Available To guarantee food security and job creation of small scale farmers to commercial farmers, unproductive farms in the South 24 PGS, West Bengal need land reform program to be restructured and evaluated for agricultural productivity. This study established a potential role of remote sensing and GIS for identification and mapping of salinity zone and spatial planning of agricultural land over the Basanti and Gosaba Islands(808.314sq. km of South 24 PGS. District of West Bengal. The primary data i.e. soil pH, Electrical Conductivity (EC and Sodium Absorption ratio (SAR were obtained from soil samples of various GCP (Ground Control Points locations collected at 50 mts. intervals by handheld GPS from 0–100 cm depths. The secondary information is acquired from the remotely sensed satellite data (LANDSAT ETM+ in different time scale and digital elevation model. The collected field samples were tested in the laboratory and were validated with Remote Sensing based digital indices analysisover the temporal satellite data to assess the potential changes due to over salinization. Soil physical properties such as texture, structure, depth and drainage condition is stored as attributes in a geographical soil database and linked with the soil map units. The thematic maps are integrated with climatic and terrain conditions of the area to produce land capability maps for paddy. Finally, The weighted overlay analysis was performed to assign theweights according to the importance of parameters taken into account for salineareaidentification and mapping to segregate higher, moderate, lower salinity zonesover the study area.

  16. Effect of inorganic nitrogenous fertilizer on productivity of recently reclaimed saline sodic soils with and without biofertilizer.

    Science.gov (United States)

    Mehdi, S M; Sarfraz, M; Shabbir, G; Abbas, G

    2007-07-15

    Saline sodic soils after reclamation become infertile due to leaching of most of the nutrients along with salts from the rooting medium. Microbes can play a vital role in the productivity improvement of such soils. In this study a saline sodic field having EC, 6.5 dS m(-1), pH, 9.1 and gypsum requirement (GR) 3.5 tons acre(-1) was reclaimed by applying gypsum at the rate of 100% GR. Rice and wheat crops were transplanted/sown for three consecutive years. Inorganic nitrogenous fertilizer was used with and without biofertilizers i.e., Biopower (Azospirillum) for rice and diazotroph inoculums for wheat. Nitrogen was applied at the rate of 0, 75% of recommended dose (RD), RD, 125% of RD and 150% of RD. Recommended dose of P without K was applied to all the plots. Biopower significantly improved Paddy and straw yield of rice over inorganic nitrogenous fertilizer. In case of wheat diazotroph inoculum improved grain and straw yield significantly over inorganic nitrogenous fertilizer. Among N fertilizer rates, RD + 25% additional N fertilizer was found to be the best dose for rice and wheat production in recently reclaimed soils. Nitrogen concentration and its uptake by paddy, grain and straw were also increased by biopower and diazotroph inoculum over inorganic nitrogenous fertilizer. Among N fertilizer rates, RD + 25% additional N fertilizer was found to be the best dose for nitrogen concentration and its uptake by paddy, grain and straw. Total soil N, available P and extractable K were increased while salinity/sodicity parameters were decreased with the passage of time. The productivity of the soil was improved more by biofertilizers over inorganic N fertilizers.

  17. Assessing environmental impacts of treated wastewater through monitoring of fecal indicator bacteria and salinity in irrigated soils.

    Science.gov (United States)

    McLain, Jean E T; Williams, Clinton F

    2012-03-01

    To assess the potential for treated wastewater irrigation to impact levels of fecal indicator bacteria (FIB) and salinity in irrigated soils, levels of Escherichia coli, Enterococcus, and environmental covariates were measured in a treated wastewater holding pond (irrigation source water), water leaving the irrigation system, and in irrigated soils over 2 years in a municipal parkland in Arizona. Higher E. coli levels were measured in the pond in winter (56 CFU 100 mL(-1)) than in summer (17 CFU 100 mL(-1)); however, in the irrigation system, levels of FIB decreased from summer (26 CFU 100 mL(-1)) to winter (4 CFU 100 mL(-1)), possibly related to low winter water use and corresponding death of residual bacteria within the system. For over 2 years, no increase in FIB was found in irrigated soils, though highest E. coli levels (700 CFU g(-1) soil) were measured in deeper (20-25 cm) soils during summer. Measurements of water inputs vs. potential evapotranspiration indicate that irrigation levels may have been sufficient to generate bacterial percolation to deeper soil layers during summer. No overall increase in soil salinity resulting from treated wastewater irrigation was detected, but distinct seasonal peaks as high as 4 ds m(-1) occurred during both summers. The peaks significantly declined in winter when surface ET abated and more favorable water balances could be maintained. Monitoring of seasonal shifts in irrigation water quality and/or factors correlated with increases and decreases in FIB will aid in identification of any public health or environmental risks that could arise from the use of treated wastewater for irrigation.

  18. Detecting the Spatio-temporal Distribution of Soil Salinity and Its Relationship to Crop Growth in a Large-scale Arid Irrigation District Based on Sampling Experiment and Remote Sensing

    Science.gov (United States)

    Ren, D.; Huang, G., Sr.; Xu, X.; Huang, Q., Sr.; Xiong, Y.

    2016-12-01

    Soil salinity analysis on a regional scale is of great significance for protecting agriculture production and maintaining eco-environmental health in arid and semi-arid irrigated areas. In this study, the Hetao Irrigation District (Hetao) in Inner Mongolia Autonomous Region, with suffering long-term soil salinization problems, was selected as the case study area. Field sampling experiments and investigations related to soil salt contents, crop growth and yields were carried out across the whole area, during April to August in 2015. Soil salinity characteristics in space and time were systematically analyzed for Hetao as well as the corresponding impacts on crops. Remotely sensed map of soil salinity distribution for surface soil was also derived based on the Landsat OLI data with a 30 m resolution. The results elaborated the temporal and spatial dynamics of soil salinity and the relationships with irrigation, groundwater depth and crop water consumption in Hetao. In addition, the strong spatial variability of salinization was clearly presented by the remotely sensed map of soil salinity. Further, the relationship between soil salinity and crop growth was analyzed, and then the impact degrees of soil salinization on cropping pattern, leaf area index, plant height and crop yield were preliminarily revealed. Overall, this study can provide very useful information for salinization control and guide the future agricultural production and soil-water management for the arid irrigation districts analogous to Hetao.

  19. Field-Scale Spatial Variation of Saline-Sodic Soil and Its Relation with Environmental Factors in Western Songnen Plain of China

    Directory of Open Access Journals (Sweden)

    Xiongrui Yin

    2011-01-01

    Full Text Available The objectives of this study were to investigate the degree of spatial variability and variance structure of salinization parameters using classical and geostatistical method in Songnen Plain of China, which is one of largest saline-sodic areas in the World, and to analyze the relationship between salinization parameters, including soil salinity content (SC, electrical conductivity (EC, sodium adsorption ratio (SAR, and pH, and seven environmental factors by Pearson and stepwise regression analysis. The environmental factors were ground elevation, surface ponding time, surface ponding depth, and soil moistures at four layers (0–10 cm, 10–30 cm, 30–60 cm, and 60–100 cm. The results indicated that SC, EC, and SAR showed great variations, whereas pH exhibited low variations. Four salinization parameters showed strongly spatial autocorrelation resulting from the compound impact of structural factors. The empirical semivariograms in the four parameters could be simulated by spherical and exponential models. The spatial distributions of SC, EC, SAR and pH showed similar patterns, with the coexistence of high salinity and sodicity in the areas with high ground elevation. By Pearson analysis, the soil salinization parameters showed a significant positive relationship with ground elevation, but a negative correlation with surface ponding time, surface ponding depth, and soil moistures. Both correlation and stepwise regression analysis showed that ground elevation is the most important environmental factor for spatial variation of soil sanilization. The results from this research can provide some useful information for explaining mechanism of salinization process and utilization of saline-sodic soils in the Western Songnen Plain.

  20. Field-scale spatial variation of saline-sodic soil and its relation with environmental factors in Western Songnen Plain of China.

    Science.gov (United States)

    Yang, Fan; Zhang, Guangxin; Yin, Xiongrui; Liu, Zhijun

    2011-02-01

    The objectives of this study were to investigate the degree of spatial variability and variance structure of salinization parameters using classical and geostatistical method in Songnen Plain of China, which is one of largest saline-sodic areas in the World, and to analyze the relationship between salinization parameters, including soil salinity content (SC), electrical conductivity (EC), sodium adsorption ratio (SAR), and pH, and seven environmental factors by Pearson and stepwise regression analysis. The environmental factors were ground elevation, surface ponding time, surface ponding depth, and soil moistures at four layers (0-10 cm, 10-30 cm, 30-60 cm, and 60-100 cm). The results indicated that SC, EC, and SAR showed great variations, whereas pH exhibited low variations. Four salinization parameters showed strongly spatial autocorrelation resulting from the compound impact of structural factors. The empirical semivariograms in the four parameters could be simulated by spherical and exponential models. The spatial distributions of SC, EC, SAR and pH showed similar patterns, with the coexistence of high salinity and sodicity in the areas with high ground elevation. By Pearson analysis, the soil salinization parameters showed a significant positive relationship with ground elevation, but a negative correlation with surface ponding time, surface ponding depth, and soil moistures. Both correlation and stepwise regression analysis showed that ground elevation is the most important environmental factor for spatial variation of soil sanilization. The results from this research can provide some useful information for explaining mechanism of salinization process and utilization of saline-sodic soils in the Western Songnen Plain.

  1. Effects of environmental conditions on soil salinity and arid region in Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Ben Ahmed, C.; Ben Rouina, B.; Boukhris, M.

    2009-07-01

    The shortage of water resources of good water quality is becoming an issue in the arid and semi arid regions. for this reason, the use of water resources of marginal quality such as treated wastewater and saline groundwater has become and important consideration, particularly in arid region in Tunisia, where large quantities of saline water are used for irrigation. (Author)

  2. Water Relations and Transpiration of Quinoa (Chenopodium quinoa Willd.) Under Salinity and Soil Drying

    DEFF Research Database (Denmark)

    Razzaghi, Fatemeh; Ahmadi, Seyed Hamid; Adolf, Verena Isabelle

    2011-01-01

    Drought and salinity are the two major factors limiting crop growth and production in arid and semi-arid regions. The separate and combined effects of salinity and progressive drought in quinoa (Chenopodium quinoa Willd.) were studied in a greenhouse experiment. Stomatal conductance (gs), leaf...

  3. EFFECT OF THE INTRECATION BETWWEN SALINE IRRIGATION WATER AND DRIP IRRIGATION SYSTEM (SUB-SURFACE) ON CHEMICAL AND PHYSICAL PROPERTIES OF THE SOIL IN ABU GHARIB DISTRICT

    OpenAIRE

    Mohammed Abed Jameel*, Dr Ibtisam Raheem Karim, Dr Abdul Khaliq Saleh Nima,

    2017-01-01

    A field study was conducted in Soil Research Department (Ministry of Agriculture), located in Abu Ghraib district to study the effect of irrigation water salinity and drip irrigation system on soil properties according to using of drip irrigation system (under the surface) and through specific scenarios included the quality of water used (S): 1. Tap water (): (0.6 - 0.7 ds/m), 2. Medium-salinity water (): (2.6 – 3.0 ds/m), 3. High-salinity water (): (4.9 – 5.1 ds/m), and 4. The alternating ir...

  4. Influence of Organic Amendment and Compaction on Nutrient Dynamics in a Saturated Saline-Sodic Soil from the Riparian Zone.

    Science.gov (United States)

    Miller, J J; Bremer, E; Curtis, T

    2016-07-01

    Cattle grazing in wet riparian pastures may influence nutrient dynamics due to nutrient deposition in feces and urine, soil compaction, and vegetation loss. We conducted a lab incubation study with a saline-sodic riparian soil to study nutrient (N, P, S, Fe, Mn, Cu, and Zn) dynamics in soil pore water using Plant Root Simulator (PRS) probes and release of nutrients into the overlying ponded water during flooding. The treatment factors were organic amendment (manure, roots, and unamended control), compaction (compacted, uncompacted), and burial time (3, 7, and 14 d). Amendment treatment had the greatest impact on nutrient dynamics, followed by burial time, whereas compaction had little impact. The findings generally supported our hypothesis that organic amendments should first increase nitrate loss, then increase Mn mobility, then Fe mobility and associated release of P, and finally increase sulfate loss. Declines in nitrate due to amendment addition were small because nitrate was at low levels in all treatments due to high denitrification potential instead of being released to soil pore water or overlying water. Addition of organic amendment strongly increased Mn and Fe concentrations in overlying water and of adsorbed Fe on PRS probes but only increased Mn on PRS probes on Day 3 due to subsequent displacement from ion exchange membranes. Transport of P to overlying water was increased by organic amendment addition but less so for manure than roots despite higher P on PRS probes. The findings showed that saline-sodic soils in riparian zones are generally a nutrient source for P and are a nutrient sink for N as measured using PRS probes after 3 to 7 d of flooding. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  5. Effects of humic acid-based buffer + cation on chemical characteristics of saline soils and maize growth

    Directory of Open Access Journals (Sweden)

    W. Mindari

    2014-10-01

    Full Text Available Humic acid is believed to maintain the stability of the soil reaction, adsorption / fixation / chelate of cation, thereby increasing the availability of water and plant nutrients. On the other hand, the dynamics of saline soil cation is strongly influenced by the change of seasons that disrupt water and plant nutrients uptake. This experiment was aimed to examine the characteristics of the humic acid from compost, coal, and peat and its function in the adsorption of K+ and NH4+ cations, thus increasing the availability of nutrients and of maize growth. Eighteen treatments consisted of three humic acid sources (compost, peat and coal, two cation additives (K+ and NH4+, and three doses of humic acid-based buffer (10, 20, and 30 g / 3kg, were arranged in a factorial completely randomized with three replicates. The treatments were evaluated against changes in pH, electric conductivity (EC, cation exchange capacity (CEC, chlorophyll content, plant dry weight and plant height. The results showed that the addition of K+ and NH4+ affected pH, CEC, K+, NH4+, and water content of the buffer. Application of humic acid-based buffer significantly decreased soil pH from > 7 to about 6.3, decreased soil EC to 0.9 mS / cm, and increased exchangeable Na from 0.40 to 0.56 me / 100g soil, Ca from 15.57 to 20.21 me/100 g soil, Mg from 1.76 to 6.52 me/100 g soil, and K from 0.05-0.51 me / 100g soil. Plant growth (plant height, chlorophyll content, leaf area, and stem weight at 35 days after planting increased with increasing dose of humic acid. The dose of 2.0g peat humic acid + NH4+ / 3 kg of soil or 30g peat humic acid + K+ / 3 kg of oil gave the best results of maize growth.

  6. PHYSIOLOGICAL REACTION OF THE SPECIES BRASSICA JUNCEA (L. CZERN. ON SALINIZED SOILS AMELIORATED WITH ZEOLITIC TUFF, PEAT AND PERLITE

    Directory of Open Access Journals (Sweden)

    Maria Cătălina PASTIA

    2017-12-01

    Full Text Available The physiological reaction of saline stress which Brassica juncea (L. Czern. plants undergo shows a greater growth and fresh substance gain process on previously cultivated soils that were fined with 20% zeolitic tuff and 5.09 g of neutral peat than the ones that had a substrate which hasn’t been cultivated on before that was fined with 5% zeolitic tuff and 1.39 g of perlite. The dry substance values obtained present a positive correlation with the values of fresh substance. Analysis of stomatal conductance enhances the hydric stress of plants which respond to saline stress with osmotic adjustment, accumulating high quantities of water comparing to the witness plant, which induces lower values of stomatal conductance and implicitly values are decreasing for photosynthesis, determining a low productivity. Higher values of stomatal conductance are reached at plants grown on previously cultivated soils fined with 20% zeolitic tuff and peat, and also at the ones grown on uncultivated soils fined with peat (29.45, respectively 30.05 mmol/m2/s.

  7. Growth and yield components of wheat genotypes as influenced by potassium and farm yard manure on a saline sodic soil

    Directory of Open Access Journals (Sweden)

    Muhammad Ashraf, Muhammad Afzal

    2011-11-01

    Full Text Available The adequate supply of mineral nutrients through chemical fertilizers and manure may help to sustain the crop productivity and ensure plant survival under salinity stress. A field study was conducted on saline sodic soil (ECe = 13 dS m-1, SAR 23.3 (mmol L-11/2, pH = 8.6 of surface 15 cm layer to quantify the effects of potassium (K and farm yard manure (FYM on two wheat genotypes differing in salinity tolerance. Three K levels (0, 80, 120 kg ha-1 and two FYM levels (0, 10 t ha-1 were tested using randomized compete block design (RCBD with three replications. The application of K along with FYM reduced Na+ uptake and accumulation in plant tissue. The K concentration and K+/ Na+ ratio were significantly improved in both wheat genotypes with the supplementation of K and FYM. The grain yield was improved by 40-156% in salt tolerant genotype and 46-206% in salt sensitive genotype with added K and FYM. Similar trend was observed in yield components. Ameliorative effects of added K and FYM were more marked in salt sensitive genotype (Auqab-2000 than in salt tolerant (Inqlab-91. Grain yield of salt sensitive and salt tolerant wheat genotypes was positively correlated with leaf K+ concentration determined at various treatments. Addition of K along with FYM decreased sodium adsorption ratio (SAR and electrical conductivity (EC of soil particularly in upper layers. Therefore, it is concluded that K along with FYM could help to alleviate deleterious effects of salts and thus improve the productivity of salt affected soils.

  8. Remediation of saline-sodic soil with flue gas desulfurization gypsum in a reclaimed tidal flat of southeast China.

    Science.gov (United States)

    Mao, Yumei; Li, Xiaping; Dick, Warren A; Chen, Liming

    2016-07-01

    Salinization and sodicity are obstacles for vegetation reconstruction of coastal tidal flat soils. A study was conducted with flue gas desulfurization (FGD)-gypsum applied at rates of 0, 15, 30, 45 and 60Mg/ha to remediate tidal flat soils of the Yangtze River estuary. Exchangeable sodium percentage (ESP), exchangeable sodium (ExNa), pH, soluble salt concentration, and composition of soluble salts were measured in 10cm increments from the surface to 30cm depth after 6 and 18months. The results indicated that the effect of FGD-gypsum is greatest in the 0-10cm mixing soil layer and 60Mg/ha was the optimal rate that can reduce the ESP to below 6% and decrease soil pH to neutral (7.0). The improvement effect was reached after 6months, and remained after 18months. The composition of soluble salts was transformed from sodic salt ions mainly containing Na(+), HCO3(-)+CO3(2-) and Cl(-) to neutral salt ions mainly containing Ca(2+) and SO4(2-). Non-halophyte plants were survived at 90%. The study demonstrates that the use of FGD-gypsum for remediating tidal flat soils is promising. Copyright © 2016. Published by Elsevier B.V.

  9. Soil hydromorphism in two saline and brackish system: classification, indicators and pedogenetic processes

    Directory of Open Access Journals (Sweden)

    Chiara Ferronato

    2015-12-01

    Full Text Available The introduction of the “subaqueous soils” into the international classification system of the Soil Taxonomy (2010 gives a possibility to soil scientists to use the pedogenetic approach to investigate coastal soils in view of resource protection and valorization. Coastal areas, in fact, are complex and fragile ecosystems whose ecological value is worldwide recognized, but generally highly inhabited and affected by different erosion and pollution phenomena, and flooding problems. The soil science has a great opportunity to contribute to the correct management and protection of coastal soils, by recognizing the value of coastal soils and thus investigating the effect of the water table oscillation and ionic composition to the changes of soil properties and functionality. This work represent a first attempt to describe the soil continuum existing from hydromorphic to subaqueous environment, highlighting the evidence of some pedogenetic processes into subaquatic substrates and demonstrating the high ecological values of these pedons.

  10. Isolation of plant-growth-promoting rhizobacteria from rhizospheric soil of halophytes and their impact on maize (Zea mays L.) under induced soil salinity.

    Science.gov (United States)

    Ullah, Sami; Bano, Asghari

    2015-04-01

    The present investigation was aimed to scrutinize the salt tolerance potential of plant-growth-promoting rhizobacteria (PGPR) isolated from rhizospheric soil of selected halophytes (Atriplex leucoclada, Haloxylon salicornicum, Lespedeza bicolor, Suaeda fruticosa, and Salicornica virginica) collected from high-saline fields (electrical conductivity 4.3-5.5) of District Mardan, Pakistan. Five PGPR strains were identified using 16S rRNA amplification and sequence analysis. Bacillus sp., isolated from rhizospheric soil of Atriplex leucoclada, and Arthrobacter pascens, isolated from rhizospheric soil of Suaeda fruticosa, are active phosphate solubilizers and bacteriocin and siderophore producers; hence, their inoculation and co-inoculation on maize ('Rakaposhi') under induced salinity stress enhanced shoot and root length and shoot and root fresh and dry mass. The accumulation of osmolytes, including sugar and proline, and the elevation of antioxidant enzymes activity, including superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase, were enhanced in the maize variety when inoculated and co-inoculated with Bacillus sp. and Arthrobacter pascens. The PGPR (Bacillus sp. and A. pascens) isolated from the rhizosphere of the mentioned halophytes species showed reliability in growth promotion of maize crop in all the physiological parameters; hence, they can be used as bio-inoculants for the plants growing under salt stress.

  11. Evaluation of soil and water salinity for irrigation in North-eastern ...

    African Journals Online (AJOL)

    GREG

    2013-05-08

    May 8, 2013 ... Soil samples were collected from bore holes of three soil mapping units of the study site across depth and water samples were .... mean annual maximum and minimum temperature was 38and. 10.3°C, respectively. December is the coldest ... Walkley and black (1934). Soil texture was determined by the.

  12. Biochar applied with appropriate rates can reduce N leaching, keep N retention and not increase NH3 volatilization in a coastal saline soil.

    Science.gov (United States)

    Sun, Haijun; Lu, Haiying; Chu, Lei; Shao, Hongbo; Shi, Weiming

    2017-01-01

    The impacts of biochar addition on nitrogen (N) leaching, (ammonia) NH3 volatilization from coastal saline soils are not well understood. In this soil column study, the effects of wheat straw biochar application at rates of 0.5%, 1%, 2% and 4% by weight to a coastal saline soil on N leaching, NH3 volatilization, soil pH and N retention were investigated. Results showed that 0.5% and 1% biochar amendments reduce the NH4+-N, NO3--N and total N concentrations of leachate and thereby significantly decrease their cumulative lost loads by 11.6-24.0%, 13.2-29.7%, and 14.6-26.0%, respectively, in compared with the control. The biochar-induced soil N leaching mitigation efficiency was weakened when the biochar application rates increased to 2% and 4%. However, the impact of biochar addition on cumulative NH3 volatilizations were negative and significantly 25.6-53.6% higher NH3 volatilizations in soils with 2% and 4% biochar amended than control were detected, which was mainly attributed to the averaged 0.53-0.88units higher soil pH as results of biochar addition. On average, the total N concentrations of soil were kept same with 1.01-1.06gkg-1 under control and biochar treatments. Therefore, biochar application to the coastal saline soils with appropriate rates (i.e., 0.5% and 1% in current study) can reduce N leaching, keep soil N retention, and not increase NH3 volatilization, which was beneficial for sustainable use of saline soils. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Use of textile waste water along with liquid NPK fertilizer for production of wheat on saline sodic soils.

    Science.gov (United States)

    Yaseen, Muhammad; Aziz, Muhammad Zahir; Jafar, Abdul Aleem; Naveed, Muhammad; Saleem, Muhammad

    2016-01-01

    A field experiment in collaboration with a private textile industry (Noor Fatima Fabrics Private (Ltd.), Faisalabad) was conducted to evaluate the effect of disposed water from bleaching unit, printing unit and end drain for improving growth and yield of wheat under saline sodic soil. Textile waste water along with canal water (control) was applied with and without liquid NPK fertilizer. The application of liquid NPK fertilizer with end drain waste water increased plant height, spike length, flag leaf length, root length, number of tillers (m(-2)), number of fertile tillers (m(-2)), 1000 grain weight, grain yield, straw yield and biological yield up to 21, 20, 20, 44, 17, 20, 14, 44, 40 and 41%, respectively compared to canal water (control). Similarly, the NPK uptake in grain was increased up to 15, 30 and 28%, respectively by liquid fertilizer treated end drain water as compare to canal water with liquid fertilizer. Moreover, concentration of different heavy metals particularly Cu, Cr, Pb and Cd was decreased in grains by application of waste water along with liquid NPK. The result may imply that waste water application along with liquid-NPK could be a novel approach for improving growth and yield of wheat in saline sodic soils.

  14. The effect of increasing salinity and forest mortality on soil nitrogen and phosphorus mineralization in tidal freshwater forested wetlands

    Science.gov (United States)

    Noe, Gregory B.; Krauss, Ken W.; Lockaby, B. Graeme; Conner, William H.; Hupp, Cliff R.

    2013-01-01

    Tidal freshwater wetlands are sensitive to sea level rise and increased salinity, although little information is known about the impact of salinification on nutrient biogeochemistry in tidal freshwater forested wetlands. We quantified soil nitrogen (N) and phosphorus (P) mineralization using seasonal in situ incubations of modified resin cores along spatial gradients of chronic salinification (from continuously freshwater tidal forest to salt impacted tidal forest to oligohaline marsh) and in hummocks and hollows of the continuously freshwater tidal forest along the blackwater Waccamaw River and alluvial Savannah River. Salinification increased rates of net N and P mineralization fluxes and turnover in tidal freshwater forested wetland soils, most likely through tree stress and senescence (for N) and conversion to oligohaline marsh (for P). Stimulation of N and P mineralization by chronic salinification was apparently unrelated to inputs of sulfate (for N and P) or direct effects of increased soil conductivity (for N). In addition, the tidal wetland soils of the alluvial river mineralized more P relative to N than the blackwater river. Finally, hummocks had much greater nitrification fluxes than hollows at the continuously freshwater tidal forested wetland sites. These findings add to knowledge of the responses of tidal freshwater ecosystems to sea level rise and salinification that is necessary to predict the consequences of state changes in coastal ecosystem structure and function due to global change, including potential impacts on estuarine eutrophication.

  15. Influence of NaCl-Induced Salinity and Cd Toxicity on Respiration Activity and Cd Availability to Barley Plants in Farmyard Manure-Amended Soil

    Directory of Open Access Journals (Sweden)

    Adel R. A. Usman

    2015-01-01

    Full Text Available The objective of this study was to evaluate the Cd availability and toxicity as affected by NaCl-induced salinity and farmyard manure addition. The Cd availability and toxicity were investigated in greenhouse pot and incubation experiments were conducted on a calcareous loamy sand soil contaminated with Cd (0.5, 1.5, 3, 6, 12, and 24 mg kg−1 of soil and amended with two rates of 0.0 and 30 g farmyard manure (FYM kg−1. Barley seeds (Hordeum vulgare L. were sown in pots and irrigated with water containing different levels of salinity (0, 30, 60, and 120 mM NaCl. The results revealed that the DTPA-extractable Cd and its content in barley plant shoots tended to increase in line as Cd was applied and salt levels increased. Elevated decreases in the soil basal respiration with increased Cd applied and NaCl-induced salinity were found. However, applying FYM significantly reduced Cd availability and increased plant growth and soil respiration activity. The results clearly showed that adding farmyard manure as soil organic amendment decreased the availability of Cd to barley plants and mitigated the toxicity of both Cd and salinity to soil microbial activity.

  16. Soil microbial diversity, site conditions, shelter forest land, saline water drip-irrigation, drift desert.

    Science.gov (United States)

    Jin, Zhengzhong; Lei, Jiaqiang; Li, Shengyu; Xu, Xinwen

    2013-10-01

    Soil microbes in forest land are crucial to soil development in extreme areas. In this study, methods of conventional culture, PLFA and PCR-DGGE were utilized to analyze soil microbial quantity, fatty acids and microbial DNA segments of soils subjected to different site conditions in the Tarim Desert Highway forest land. The main results were as follows: the soil microbial amount, diversity indexes of fatty acid and DNA segment differed significantly among sites with different conditions (F soil microbial community (>84%), followed by actinomycetes and then fungi (soil microbial diversity were insignificant at 0-35 cm. Correlation analysis indicated that the forest trees grew better as the soil microbial diversity index increased. Therefore, construction of the Tarim Desert Highway shelter-forest promoted soil biological development; however, for enhancing sand control efficiency and promoting sand development, we should consider the effects of site condition in the construction and regeneration of shelter-forest ecological projects. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Ecophysiological response of Crambe maritima to airborne and soil-borne salinity.

    NARCIS (Netherlands)

    de Vos, A.C.; Broekman, R.A.; Groot, M.P.; Rozema, J.

    2010-01-01

    Background and Aims: There is a need to evaluate the salt tolerance of plant species that can be cultivated as crops under saline conditions. Crambe maritima is a coastal plant, usually occurring on the driftline, with potential use as a vegetable crop. The aim of this experiment was to determine

  18. A Proposed Extension to the Soil Moisture and Ocean Salinity Level 2 Algorithm for Mixed Forest and Moderate Vegetation Pixels

    Science.gov (United States)

    Panciera, Rocco; Walker, Jeffrey P.; Kalma, Jetse; Kim, Edward

    2011-01-01

    The Soil Moisture and Ocean Salinity (SMOS)mission, launched in November 2009, provides global maps of soil moisture and ocean salinity by measuring the L-band (1.4 GHz) emission of the Earth's surface with a spatial resolution of 40-50 km.Uncertainty in the retrieval of soilmoisture over large heterogeneous areas such as SMOS pixels is expected, due to the non-linearity of the relationship between soil moisture and the microwave emission. The current baseline soilmoisture retrieval algorithm adopted by SMOS and implemented in the SMOS Level 2 (SMOS L2) processor partially accounts for the sub-pixel heterogeneity of the land surface, by modelling the individual contributions of different pixel fractions to the overall pixel emission. This retrieval approach is tested in this study using airborne L-band data over an area the size of a SMOS pixel characterised by a mix Eucalypt forest and moderate vegetation types (grassland and crops),with the objective of assessing its ability to correct for the soil moisture retrieval error induced by the land surface heterogeneity. A preliminary analysis using a traditional uniform pixel retrieval approach shows that the sub-pixel heterogeneity of land cover type causes significant errors in soil moisture retrieval (7.7%v/v RMSE, 2%v/v bias) in pixels characterised by a significant amount of forest (40-60%). Although the retrieval approach adopted by SMOS partially reduces this error, it is affected by errors beyond the SMOS target accuracy, presenting in particular a strong dry bias when a fraction of the pixel is occupied by forest (4.1%v/v RMSE,-3.1%v/v bias). An extension to the SMOS approach is proposed that accounts for the heterogeneity of vegetation optical depth within the SMOS pixel. The proposed approach is shown to significantly reduce the error in retrieved soil moisture (2.8%v/v RMSE, -0.3%v/v bias) in pixels characterised by a critical amount of forest (40-60%), at the limited cost of only a crude estimate of the

  19. Phytoremediation of azoxystrobin and its degradation products in soil by P. major L. under cold and salinity stress.

    Science.gov (United States)

    Romeh, Ahmed Ali Ali

    2017-10-01

    Azoxystrobin is a broad-spectrum, systemic and soil-applied fungicide used for crop protection against the four major classes of pathogenic fungi. The use of azoxystrobin use has induced water pollution and ecotoxicological effects upon aquatic organisms, long half-life in soils, as well as heath issues. Such issues may be solved by phytoremediation. Here, we tested the uptake and translocation of azoxystrobin and its degradation products by Plantago major, under cold stress and salt stress. The result demonstrated that azoxystrobin significantly accumulated in P. major roots under salinity conditions more than that in the P. major roots under cold conditions and natural condition within two days of experimental period. In P. major roots and leaves, the chromatograms of HPLC for azoxystrobin and metabolites under natural condition (control) and stressed samples (cold stress and salt stress) show different patterns of metabolism pathways reflecting changes in the degradation products. Azoxystrobin carboxylic acid (AZ-acid) formed by methyl ester hydrolysis was an important route in the roots and the leaves. AZ-pyOH and AZ-benzoic were detected in P. major roots under cold and salt stress, while did not detected in P. major roots under natural condition. In the leaves, AZ-pyOH and AZ-benzoic were detected in all treatments between 4 and 12days of exposure. Shoots of the stressed plants had greater H2O2 and proline contents than was observed in the control plants. The level of 100mM NaCl treatment induced significantly higher peroxidase (POD) activity than the non-treated control group. Leaf Chlorophyll contents in the plants at 80 and 100mM NaCl were significantly reduced than was observed in the control plants. I concluded that P. major had a high potential to contribute to remediation of saline-soil contaminated with azoxystrobin. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Evaluation of soil and water salinity for irrigation in North-eastern ...

    African Journals Online (AJOL)

    For sound land use and water management in irrigated area, knowledge of the chemical composition of soils, water, climate, drainage condition and irrigation methods before action are crucial for sustainability of irrigation projects. The study aimed to evaluate the physicochemical properties of soils and water for intended ...

  1. Effect of irrigation on soil salinity profiles along the Lower Vaal River ...

    African Journals Online (AJOL)

    The impact of long-term irrigation on semi-arid soils along the Lower Vaal River in central South Africa was assessed. Irrigated sandy and clayey soils representative of relatively homogeneous agro-ecosystems were sampled at 200 mm intervals to a depth of 2 m wherever possible. To serve as a reference, adjacent virgin ...

  2. Integrated Electrokinetics-Adsorption Remediation of Saline-Sodic Soils: Effects of Voltage Gradient and Contaminant Concentration on Soil Electrical Conductivity

    Directory of Open Access Journals (Sweden)

    Mohammed Hussain Essa

    2013-01-01

    Full Text Available In this study, an integrated in situ remediation technique which couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic clay soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg, was used in this study to investigate the effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil electrical conductivity. Box-Behnken Design (BBD was used for the experimental design and response surface methodology (RSM was employed to model, optimize, and interpret the results obtained using Design-Expert version 8 platform. The total number of experiments conducted was 15 with voltage gradient, polarity reversal rate, and initial contaminant concentration as variables. The main target response discussed in this paper is the soil electrical conductivity due to its importance in electrokinetic remediation process. Responses obtained were fitted to quadratic models whose R2 ranges from 84.66% to 99.19% with insignificant lack of fit in each case. Among the investigated factors, voltage gradient and initial contaminant concentration were found to be the most significant influential factors.

  3. Integrated electrokinetics-adsorption remediation of saline-sodic soils: effects of voltage gradient and contaminant concentration on soil electrical conductivity.

    Science.gov (United States)

    Essa, Mohammed Hussain; Mu'azu, Nuhu Dalhat; Lukman, Salihu; Bukhari, Alaadin

    2013-01-01

    In this study, an integrated in situ remediation technique which couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic clay soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg), was used in this study to investigate the effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil electrical conductivity. Box-Behnken Design (BBD) was used for the experimental design and response surface methodology (RSM) was employed to model, optimize, and interpret the results obtained using Design-Expert version 8 platform. The total number of experiments conducted was 15 with voltage gradient, polarity reversal rate, and initial contaminant concentration as variables. The main target response discussed in this paper is the soil electrical conductivity due to its importance in electrokinetic remediation process. Responses obtained were fitted to quadratic models whose R (2) ranges from 84.66% to 99.19% with insignificant lack of fit in each case. Among the investigated factors, voltage gradient and initial contaminant concentration were found to be the most significant influential factors.

  4. Cyclic use of saline and non-saline water to increase water use efficiency and soil sustainability on drip irrigated maize in a semi-arid region

    Energy Technology Data Exchange (ETDEWEB)

    Hassanli, M.; Ebrahimian, H.

    2016-07-01

    Use of saline water for irrigation is a strategy to mitigate water shortage. The objective of this study was to investigate the impact of the cyclic and constant use of saline and non-saline water on drip irrigated maize yield and irrigation water use efficiency (IWUE). Nine field treatments were laid out based on alternative irrigation management of non-saline and saline water combinations. The treatments were: two salinity levels of 3.5 and 5.7 dS/m and freshwater (0.4 dS/m) application in every one, three and five saline water application (1:1, 3:1 and 5:1, respectively). Results showed that the 1:1 combination management was the best in terms of crop yield and IWUE. In this treatment, salt concentration at the end of growing season was not significantly changed compared to its initial condition. If off-season precipitation or leaching was available, the 3:1 and 5:1 treatments were appropriated. Highest and lowest values of IWUE were 15.3 and 8.7 kg/m3 for the 1:1 management using water salinity of 3.5 dS/m and the treatment of constant irrigation with water salinity of 5.7 dS/m, respectively. Under low off-season precipitations, artificial leaching is essential for land sustainability in most treatments.

  5. Soil salinity evolution and its relationship with dynamics of groundwater in the oasis of inland river basins: case study from the Fubei region of Xinjiang Province, China.

    Science.gov (United States)

    Wang, Yugang; Xiao, Duning; Li, Yan; Li, Xiaoyu

    2008-05-01

    Soil salinization is an important worldwide environmental problem, especially in arid and semi-arid regions. Knowledge of its temporal and spatial variability is crucial for the management of oasis agriculture. The study area has experienced dramatic change in the shallow groundwater table and soil salinization during the 20th century, especially in the past two decades. Classical statistics, geostatistics and geographic information system (GIS) were applied to estimate the spatial variability of the soil salt content in relation to the shallow groundwater table and land use from 1983 to 2005. Consumption of reservoir water for agricultural irrigation was the main cause of a rise in the shallow groundwater table under intense evapotranspiration conditions, and this led indirectly to soil salinization. The area of soil salt accumulation was greater in irrigated than in non-irrigated landscape types with an increasing of 40.04% from 1983 to 2005 in cropland at approximately 0.43 t ha(-1) year(-1), and an increase at approximately 0.68 t ha(-1) year(-1) in saline alkaline land. Maps of the shallow groundwater table in 1985 and 2000 were used to deduce maps for 1983 and 1999, respectively, and the registration accuracy was 99%.

  6. Determination of Nutrient Contents and In vitro Gas Production Values of Some Legume Forages Grown in the Harran Plain Saline Soils.

    Science.gov (United States)

    Boga, M; Yurtseven, S; Kilic, U; Aydemir, S; Polat, T

    2014-06-01

    The aim of this study was to determine the nutritive value of some legume species in salt-affected soils of South-East Anatolian region using chemical composition and in vitro gas production kinetics. In this study, Lotus corniculatus, Trifolium alexandrinum, Medicago sativa were sown and tested in four different locations. A 3 by 4 factorial design with 3 legume species and 4 salt levels (non salty electrical conductivity (EC)ECECEC) was used in the study. Results indicated that salinity and plants had no significant effect on ash and ether extract. Dry matter (DM), acid detergent fiber, digestible dry matter, dry matter intake (DMI) were affected by plant, salinity and plant×salinity interaction. On the other hand neutral detergent fiber, relative feed value (RFV), and DMI were affected by salinity and plant×salinity interaction. Mineral contents were affected by plant species, salinity and salinity×plants interactions. In vitro gas production, their kinetics and estimated parameters such as were not affected by salinity whereas the gas production up to 48 h, organic matter digestibility, metabolizable energy (ME), and net energy lactation (NEL) were affected by plant and plant×salt interaction. Generally RFVs of all species ranged from 120 to 210 and were quite satisfactory in salty conditions. Current results show that the feed value of Medicago sativa is higher compared to Lotus corniculatus and Trifolium alexandrinum.

  7. Ecosystem Services and Community-Based Approaches to Wastewater and Saline Soils Reclamation in the Drylands of Uzbekistan

    Science.gov (United States)

    Toderich, Kristina; Khujanazarov, Timur; Aralova, Dildora; Shuyskaya, Elena; Gismatulina, Liliya; Boboev, Hasan

    2017-04-01

    The working hypothesis of this article support an indication of declining water quality, increasing soils salinity and higher production costs in the Bukhara oasis- a borderline lands between the sandy Kyzylkum Desert and irrigated zone in the lower stream of Zarafshan River Basin. The pollution of waters and soils with toxic metals is the major environmental problem in these agro-ecological zones. Conventional remediation approaches usually do not ensure adequate results. The mobility of toxic pollutants can be highly facilitated by the chemical properties of soils and the aridity of the climate. The impact of these factors of land degradation induces reduction in biodiversity and yields losses of agricultural crops and wild desert plant communities. A recent survey showed that the chemical composition of the drainage effluents is sulfate-chloride-hydrocarbonate - magnesium-sodium-calcium with high level of mineralization 4200 - 18800 ppm. Concentration of chloride and sulfate, detected both in drainage effluents and ground water, is 10 times higher than maximum allowable concentration (MAC); and traces of heavy metals, such as strontium, selenium, arsenic, lead, zinc, uranium are 2 times higher than MAC. Distribution of boron showed a strong correlation with those of arsenic and antimony. Aluminum has a significant correlation with arsenic and lead distribution. Antimony correlates significantly with zinc and arsenic, while copper and iron (Fe57) also well correlate with each other. Because these metals rarely exist in natural environment, it is presumed that they are caused both by the usage of some chemicals at the agricultural field in harvest season and by the discharge of some technogenic chemicals from industry. The desalinated/treated wastewater were used to irrigate high value crops and the waste brine is transformed into a resource that was used to grow aquatic species (fish, algae) and irrigate halophytic species with benefits for livestock, farmers and

  8. Effect of soil salinity on the growth, amino acids and ion contents of ...

    African Journals Online (AJOL)

    Rice seedling of different transgenic lines (T-99, T-112, T-115 and T-121) were grown in sand culture with salt concentration of 0, 50, 100 and 150 mM to determine the effect of salinity on growth, amino acid, and ion contents. It was observed that all the lines could tolerate concentration of up to 50 mM of salt solution.

  9. Effect of salt-tolerant plant growth-promoting rhizobacteria on wheat plants and soil health in a saline environment.

    Science.gov (United States)

    Upadhyay, S K; Singh, D P

    2015-01-01

    Salt-tolerant plant growth-promoting rhizobacteria (ST-PGPR) significantly influence the growth and yield of wheat crops in saline soil. Wheat growth improved in pots with inoculation of all nine ST-PGPR (ECe = 4.3 dS·m(-1) ; greenhouse experiment), while maximum growth and dry biomass was observed in isolate SU18 Arthrobacter sp.; simultaneously, all ST-PGPR improved soil health in treated pot soil over controls. In the field experiment, maximum wheat root dry weight and shoot biomass was observed after inoculation with SU44 B. aquimaris, and SU8 B. aquimaris, respectively, after 60 and 90 days. Isolate SU8 B. aquimaris, induced significantly higher proline and total soluble sugar accumulation in wheat, while isolate SU44 B. aquimaris, resulted in higher accumulation of reducing sugars after 60 days. Percentage nitrogen (N), potassium (K) and phosphorus (P) in leaves of wheat increased significantly after inoculation with ST-PGPR, as compared to un-inoculated plants. Isolate SU47 B. subtilis showed maximum reduction of sodium (Na) content in wheat leaves of about 23% at both 60 and 90 days after sowing, and produced the best yield of around 17.8% more than the control. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. Impact of calcium sulphate and calcium carbide on nitrogen use efficiency of wheat in normal and saline sodic soils

    Directory of Open Access Journals (Sweden)

    I.A. Mahmood

    2009-05-01

    Full Text Available pot experiment was conducted to study the effect of calcium as CaSO4 or CaC2 (20 mg Ca kg-1 of soil from each source on N use efficiency of wheat (Triticum aestivum L. var. Inqlab-91 under normal (ECe=0.7 dS m-1, SAR=4.37 and pH=8.1 and saline-sodic soils (ECe=8.7 dS m-1, SAR=21.43 and pH=9.2 in glass house at National Agricultural Research Centre, Islamabad during Kharif season 2007-08. The crop was grown to maturity and data on tillering, plant height, panicle length, grains spike-1, straw and grain yields were recorded at the time of crop harvest. A considerable reduction in plant height (38% and grain yield (44% was observed when grown in saline-sodic soil (ECe=8.7 dS m-1 as compared to normal soil (ECe=0.7 dS m-1 while N application significantly improved plant growth and yield in both conditions. Among the treatments, N application even at lower rate supplemented with calcium as CaSO4, CaC2 or their mixture (1:1 showed better performance than that of straight N application in both soils. A 41 to 53% increase in plant growth and 36 to 44% in grain yield over control (without N were observed through N fertilization at 25 and 50 mg kg-1 of soil supplemented with calcium as CaC2 in salinesodic soil. Similarly, calcium as CaSO4 application also caused a considerable improvement in plant growth (34 to 52% and grain yield (25 to 43%. However, the effect of mixture application of CaSO4 and CaC2 (1:1 on plant growth and yield was comparatively more pronounced for both the soils. Interestingly, lower dose ofN (25 mg kg-1 with calcium as CaC2 alone or in combination with CaSO4 (1:1 supplementation showed statistically equal performance to that of higher dose (N=50 mg kg-1 alone. Tissue Na+ significantly decreased while K+ and Ca2+ concentrations were elevated due to N application along with calcium nutrition. Maximum N uptake and apparent N recovery were revealed from treatments where N was applied @ 50 mg kg-1 soil supplemented with calcium as CaC2

  11. Soil and salinity mobilization and transport in the Colorado River Basin

    Science.gov (United States)

    Cole Green Rossi; Mark A. Weitz; Kossi Nouwakpo; Ken McGwire

    2016-01-01

    Federally, the evaluated potential of soil loss risk in national reports in the past and ways to adapt to be proactive in preventing accelerated soil loss on rangelands has been incomplete. The areas where it is difficult to measure due to the complexities of multiple interactions (splash, sheet and rill formation, landscape dominated by wind and water processes,...

  12. The influence of salinity and restoration on wetland soil microbial communities and carbon cycling in the San Francisco Bay-Delta Region

    Science.gov (United States)

    Theroux, S.; Hartman, W.; He, S.; Windham-Myers, L.; Tringe, S. G.

    2014-12-01

    Climate change is predicted to increase the average salinity of the San Francisco Bay-Delta watershed as sea levels rise and alpine snow volume decreases. Wetland soil microbial communities are responsible for cycling greenhouse gases and their response to climate change will heavily influence whether increasing salinity will have a negative or positive effect on the net greenhouse gas budgets of wetlands. To better understand the underlying factors determining the balance of greenhouse gas flux in wetland soils, we targeted the microbial communities along a salinity gradient ranging from freshwater to full seawater in the San Francisco Bay-Delta region. Using DNA and RNA sequencing, coupled with greenhouse gas monitoring, we sampled sixteen sites capturing a range of wetland plant types and restoration states. We determined a suite of soil biogeochemical parameters including moisture, carbon and nutrient contents, pH, sulfate, chloride, and trace metal concentrations. The results of our microbial diversity survey (16S rRNA gene Illumina tag sequencing) showed that salinity and sampling location were the primary drivers of belowground microbial community composition. Freshwater wetland soils, with lower sulfate concentrations, produced more methane than saline sites and we found a parallel increase in the relative abundance of methanogen populations in the high-methane samples. Surprisingly, wetland restoration status did not significantly alter microbial community composition, despite orders of magnitude greater methane flux in restored wetlands compared to reference sites. Deeper metagenomic and metatranscriptomic sequencing in a restored wetland allowed us to further evaluate the roles of methanogen abundance and activity in shaping soil methane production. Our study links belowground microbial communities with their greenhouse gas production, providing a mechanistic microbial framework for assessing climate change feedbacks in wetland soils resulting from sea

  13. [Biodiversity and enzymes of culturable facultative-alkaliphilic actinobacteria in saline-alkaline soil in Fukang, Xinjiang].

    Science.gov (United States)

    Zhang, Yongguang; Liu, Qing; Wang, Hongfei; Zhang, Daofeng; Chen, Jiyue; Zhang, Yuanming; Li, Wenjun

    2014-02-04

    In order to analyze the biodiversity of cultivable facultative-alkaliphilic actinobacteria and the enzymes they produced. Total 10 soil samples were collected from saline-alkaline environments of Fukang, Xinjiang province. Facultative-alkaliphilic actinobacteria strains were isolated and identified by 16S rRNA gene sequence analysis. Enzymes including amylase, proteinase, xylanase, and cellulase were detected. Total 116 facultative-alkaliphilic actinobacterial strains and 4 alkali-tolerant actinobacterial strains were isolated from the samples, and those strains were distributed within 22 genera in 13 families and 8 orders of actinobacteria based on their 16S rRNA gene sequence analysis. The ratio of non-predominant Streptomyces and Nocardiopsis strains were 53.3%. The positive rates of amylase, proteinase, xylanase and cellulase were 35.8, 37.6, 28.3 and 17.5%, respectively. Diverse facultative-alkaliphilic actinobacteria were discovered from saline-alkaline environments of Fukang. Facultative-alkaliphilic actinobacteria are a potential source for enzymes. The study would facilitate the knowledge of the diversity of facultative-alkaliphilic actinobacteria, and provide the technical basis for exploration of facultative-alkaliphilic actinobacteria resources.

  14. The Potential of Algarrobo (Prosopis chilensis (Mol.) Stuntz) for Regeneration of Desertified Soils: Assessing Seed Germination Under Saline Conditions.

    Science.gov (United States)

    Westphal, Claus; Gachón, Paloma; Bravo, Jaime; Navarrete, Carlos; Salas, Carlos; Ibáñez, Cristian

    2015-07-01

    Due to their multipurpose use, leguminous trees are desirable for the restoration of degraded ecosystems. Our aim was to investigate seed germination of the leguminous tree Prosopis chilensis in response to salinity, one of the major abiotic challenges of desertified soils. Germination percentages of seed from 12 wild P. chilensis populations were studied. Treatments included four aqueous NaCl concentrations (150, 300, 450, and 600 mM). In each population, the highest germination percentage was seen using distilled water (control), followed closely by 150 mM NaCl. At 300 mM NaCl or higher salt concentration, germination was progressively inhibited attaining the lowest value at 450 mM NaCl, while at 600 mM NaCl germination remained reduced but with large variation among group of samples. These results allowed us to allocate the 12 groups from where seeds were collected into three classes. First, the seeds from Huanta-Rivadavia showed the lowest percent germination for each salt condition. The second group was composed of moderately salt-tolerant seeds with 75% germination at 300 mM NaCl, followed by 50% germination at 450 mM NaCl and 30% germination at 600 mM NaCl. The third group from Maitencillo and Rapel areas was the most salt tolerant with an impressive seed germination level of 97% at 300 mM NaCl, 82 % at 450 mM NaCl, and 42 % at 600 mM NaCl. Our results demonstrate that P. chilensis seeds from these latter localities have an increased germination capability under saline stress, confirming that P. chilensis is an appropriate species to rehabilitate desertified soils.

  15. The Potential of Algarrobo ( Prosopis chilensis (Mol.) Stuntz) for Regeneration of Desertified Soils: Assessing Seed Germination Under Saline Conditions

    Science.gov (United States)

    Westphal, Claus; Gachón, Paloma; Bravo, Jaime; Navarrete, Carlos; Salas, Carlos; Ibáñez, Cristian

    2015-07-01

    Due to their multipurpose use, leguminous trees are desirable for the restoration of degraded ecosystems. Our aim was to investigate seed germination of the leguminous tree Prosopis chilensis in response to salinity, one of the major abiotic challenges of desertified soils. Germination percentages of seed from 12 wild P. chilensis populations were studied. Treatments included four aqueous NaCl concentrations (150, 300, 450, and 600 mM). In each population, the highest germination percentage was seen using distilled water (control), followed closely by 150 mM NaCl. At 300 mM NaCl or higher salt concentration, germination was progressively inhibited attaining the lowest value at 450 mM NaCl, while at 600 mM NaCl germination remained reduced but with large variation among group of samples. These results allowed us to allocate the 12 groups from where seeds were collected into three classes. First, the seeds from Huanta-Rivadavia showed the lowest percent germination for each salt condition. The second group was composed of moderately salt-tolerant seeds with 75 % germination at 300 mM NaCl, followed by 50 % germination at 450 mM NaCl and 30 % germination at 600 mM NaCl. The third group from Maitencillo and Rapel areas was the most salt tolerant with an impressive seed germination level of 97 % at 300 mM NaCl, 82 % at 450 mM NaCl, and 42 % at 600 mM NaCl. Our results demonstrate that P. chilensis seeds from these latter localities have an increased germination capability under saline stress, confirming that P. chilensis is an appropriate species to rehabilitate desertified soils.

  16. Coupling of a distributed stakeholder-built system dynamics socio-economic model with SAHYSMOD for sustainable soil salinity management. Part 2: Model coupling and application

    Science.gov (United States)

    Inam, Azhar; Adamowski, Jan; Prasher, Shiv; Halbe, Johannes; Malard, Julien; Albano, Raffaele

    2017-08-01

    Many simulation models focus on simulating a single physical process and do not constitute balanced representations of the physical, social and economic components of a system. The present study addresses this challenge by integrating a physical (P) model (SAHYSMOD) with a group (stakeholder) built system dynamics model (GBSDM) through a component modeling approach based on widely applied tools such as MS Excel, Python and Visual Basic for Applications (VBA). The coupled model (P-GBSDM) was applied to test soil salinity management scenarios (proposed by stakeholders) for the Haveli region of the Rechna Doab Basin in Pakistan. Scenarios such as water banking, vertical drainage, canal lining, and irrigation water reallocation were simulated with the integrated model. Spatiotemporal maps and economic and environmental trade-off criteria were used to examine the effectiveness of the selected management scenarios. After 20 years of simulation, canal lining reduced soil salinity by 22% but caused an initial reduction of 18% in farm income, which requires an initial investment from the government. The government-sponsored Salinity Control and Reclamation Project (SCARP) is a short-term policy that resulted in a 37% increase in water availability with a 12% increase in farmer income. However, it showed detrimental effects on soil salinity in the long term, with a 21% increase in soil salinity due to secondary salinization. The new P-GBSDM was shown to be an effective platform for engaging stakeholders and simulating their proposed management policies while taking into account socioeconomic considerations. This was not possible using the physically based SAHYSMOD model alone.

  17. Delineating site-specific irrigation management units for managing soil salinity

    Science.gov (United States)

    Crop yield varies within fields due to nonuniformity of a number of factors including climate, pests, disease, management, topography, and soil. Conventional farming manages a field uniformly; as a result, conventional farming tends to wastes resources and money, and tends to detrimentally impact t...

  18. The control of saline groundwater

    NARCIS (Netherlands)

    Talsma, T.

    1963-01-01

    A study was made of the effect of the watertable, water-conducting properties of the soil, climatic factors and groundwater salinity on the salinization of soils in the Murrumbidgee Irrigation Areas, Australia.

    Average daily capillary flow rates were calculated from measured salinization (by

  19. [Influence of Mirabilis jalapa Linn. Growth on the Microbial Community and Petroleum Hydrocarbon Degradation in Petroleum Contaminated Saline-alkali Soil].

    Science.gov (United States)

    Jiao, Hai-hua; Cui, Bing-jian; Wu, Shang-hua; Bai, Zhi-hui; Huang, Zhan-bin

    2015-09-01

    In order to explore the effect of Mirabilis jalapa Linn. growth on the structure characteristics of the microbial community and the degradation of petroleum hydrocarbon (TPH) in the petroleum-contaminated saline-alkali soil, Microbial biomass and species in the rhizosphere soils of Mirabilis jalapa Linn. in the contaminated saline soil were studied with the technology of phospholipid fatty acids (PLFAs) analysis. The results showed that comparing to CK soils without Mirabilis jalapa Linn., the ratio of PLFAs species varied were 71. 4%, 69. 2% and 33. 3% in the spring, summer and autumn season, respectively. In addition, there was distinct difference of the biomasses of the microbial community between the CK and rhizosphere soils and among the difference seasons of growth of Mirabilis jalapa Linn.. Compare to CK soil, the degradation rates of total petroleum hydrocarbon (TPH) was increased by 47. 6%, 28. 3%, and 18. 9% in spring, summer, and autumn rhizosphere soils, respectively. Correlation analysis was used to determine the correlation between TPH degradation and the soil microbial community. 77. 8% of the total soil microbial PLFAs species showed positive correlation to the TPH degradation (the correlation coefficient r > 0), among which, 55. 6% of PLFAs species showed high positive correlation(the correlation coefficient was r≥0. 8). In addition, the relative content of SAT and MONO had high correlation with TPH degradation in the CK sample soils, the corelation coefficient were 0. 92 and 0. 60 respectively; However, the percent of positive correlation was 42. 1% in the rhizosphere soils with 21. 1% of them had high positive correlation. The relative content of TBSAT, MONO and CYCLO had moderate or low correlation in rhizosphere soils, and the correlation coefficient were 0. 56, 0. 50, and 0. 07 respectively. Our study showed that the growth of mirabilis Mirabilis jalapa Linn. had a higher influence on the species and biomass of microbial community in the

  20. Identifying suitable land for alternative crops in a drying climate: soil salinity, texture and topographic conditions for the growth of old man saltbush (Atriplex nummularia)

    Science.gov (United States)

    Holmes, K. W.; Barrett-Lennard, E. G.; Altman, M.

    2011-12-01

    Experiments conducted under controlled conditions clearly show that the growth and survival of plants on saltland is affected by both the levels of salinity and waterlogging (or depth to water-table) in the soil. Different plant species thrive under varying combinations of these growth constraints. However in natural settings, short distance spatial variability in soil properties and subtle topographic features often complicate the definition of saline and soil hydrological conditions; additional factors may also overprint the trends identified under controlled conditions, making it difficult to define the physical settings where planting is economically viable. We investigated the establishment and growth of old man saltbush (Atriplex nummularia) in relation to variable soil-landscape conditions across an experimental site in southwestern Australia where the combination of high salinity and occasional seasonal waterlogging ruled out the growth of traditional crops and pastures. Saltbush can be critical supplemental feed in the dry season, providing essential nutrients for sheep in combination with sufficient water and dry feed (hay). We applied a range of modeling approaches including classification and regression trees and generalized linear models to statistically characterize these plant-environment relationships, and extend them spatially using full cover raster covariate datasets. Plant deaths could be consistently predicted (97% correct classification of independent dataset) using a combination of topographic variables, salinity, soil mineralogical information, and depth to the water table. Plant growth patterns were more difficult to predict, particularly after several years of grazing, however variation in plant volume was well-explained with a linear model (r2 = 0.6, P water movement in the landscape. The final selected covariates for modeling were a digital elevation model and derivatives, soil mineralogy, competitors for water (adjacent trees) and soil

  1. Combined effects of long-term salinity and soil drying on growth, water relations, nutrient status and proline accumulation of Sesuvium portulacastrum.

    Science.gov (United States)

    Slama, Inès; Ghnaya, Tahar; Savouré, Arnould; Abdelly, Chedly

    2008-06-01

    The interaction between soil drying and salinity was studied in the perennial halophyte, Sesuvium portulacastrum. Rooted cuttings were individually cultivated for three months in silty-sandy soil under two irrigation modes: 100 and 25% of field capacity (FC). The amount of the evapotranspirated water was replaced by a nutrient solution containing either 0 or 100 mM NaCl. Whole-plant growth, leaf water content, leaf water potential (Psi(w)), and Na+, K+, and proline concentrations in the tissues were measured. When individually applied, both drought and salinity significantly restricted whole-plant growth, with a more marked effect of the former stress. However, the effects of the two stresses were not additive on whole-plant biomass or on leaf expansion. Root growth was more sensitive to salt than to soil drying, the latter being even magnified by the adverse impact of salinity. Leaf water content was significantly reduced following exposure to water-deficit stress, but was less affected in salt-treated plants. When simultaneously submitted to water-deficit stress and salinity, plants displayed higher values of water and potassium use efficiencies, leaf proline and Na+ concentrations, associated with lower leaf water potential (-1.87 MPa), suggesting the ability of S. portulacastrum to use Na+ and proline for osmotic adjustment.

  2. [Spectral data analysis of salinity soils with ground objects in the delta oasis of Weigan and Kuqa Rivers].

    Science.gov (United States)

    Zhang, Fei; Ding, Jian-li; Tashpolat; Tiyip; He, Qi-sheng

    2008-12-01

    The characteristic of landmark spectrum is not only the physical base of remote sensing technical application but also the base of the quantificational analysis of remote sensing, and the study of landmark spectrum is the main content in the basic research of remote sensing. In the present paper, the authors adopted CI700 portable spectrum apparatus made in American CID Company, and investigated or examined some spots in the delta oasis of Weigan and Kuqa rivers located in the north of Tarim Basin considered as the typical area, based on a great deal of spectral data for different kinds of geo-targets, and the spectral features and changing law of saline-alkaline ground, silver sand ground, dune, cotton ground etc. Alhagi sparsifolia., Phragmites australis, Tamarix, Halostachys caspica etc. were analyzed. According to the actual conditions, we analyzed the data noise characteristic of the spectrum and got rid of the noise. Meanwhile, derivative spectrum technology was used to remove the environmental background influence. Finally, in order to take full advantage of multi-spectrum data, ground information is absolutely necessary, and it is important to build a representative spectral library. The ENVI software was used to build the spectral library of surface features by field survey of the delta oasis of Weigan and Kuqa Rivers, Xinjiang Uygur Autonomous Region. This library can be used for features investigation, vegetation surveys, vegetation classification and environmental monitoring in the delta oasis of Weigan and Kuqa Rivers by remote sensing. The result of this research will be significant to the research on the saline-alkali soil in the arid area.

  3. Bacillus daqingensis sp. nov., a halophilic, alkaliphilic bacterium isolated from saline-sodic soil in Daqing, China.

    Science.gov (United States)

    Wang, Shuang; Sun, Lei; Wei, Dan; Zhou, Baoku; Zhang, Junzheng; Gu, Xuejia; Zhang, Lei; Liu, Ying; Li, Yidan; Guo, Wei; Jiang, Shuang; Pan, Yaqing; Wang, Yufeng

    2014-07-01

    An alkaliphilic, moderately halophilic, bacterium, designated strain X10-1(T), was isolated from saline-alkaline soil in Daqing, Heilongjiang Province, China. Strain X10-1(T) was determined to be a Gram-positive aerobe with rod-shaped cells. The isolate was catalase-positive, oxidase-negative, non-motile, and capable of growth at salinities of 0-16% (w/v) NaCl (optimum, 3%). The pH range for growth was 7.5-11.0 (optimum, pH 10.0). The genomic DNA G+C content was 47.7 mol%. Its major isoprenoid quinone was MK-7 and its cellular fatty acid profile mainly consisted of anteiso-C15:0, anteiso-C17:0, iso-C15:0, C16:0, and iso-C16:0. The peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol. Phylogenetic analysis based on 16S rRNA gene sequences showed that X10-1(T) is a member of the genus Bacillus, being most closely related to B. saliphilus DSM15402(T) (97.8% similarity) and B. agaradhaerens DSM 8721(T) (96.2%). DNA-DNA relatedness to the type strains of these species was less than 40%. On the basis of the phylogenetic, physiological, and biochemical data, strain X10-1(T) represents a novel species of the genus Bacillus, for which the name Bacillus daqingensis sp. nov. is proposed. The type strain is X10-1(T) (=NBRC 109404(T) = CGMCC 1.12295(T)).

  4. The effects of irrigation water salinity, potassium nitrate fertilization, proline spraying and leaching fraction on the growth and chemical composition of corn grown in calcareous soil

    OpenAIRE

    M.G, Nessim; Hussein, Magda A.; Moussa, A.A

    2009-01-01

    Two pot experiments were conducted to study the effect of irrigation with saline water in relation to KNO3 fertilization, proline spraying and leaching fraction on the growth and Na+, K+, Cl-, NO3 - and proline contents of corn (Zea mays L.) plant grown on a nonsaline calcareous soil. The treatments included irrigation waters of different salinity (0.54, 3.36, 5.88 or 7.95 dS/m), three rates of KNO3 (0, 4 and 8 g/pot) fertilizer and foliar application with three rates of prolin...

  5. Retrieval of Sea Surface Salinity from The NASA Soil Moisture Active Passive and Aquarius Mission Data

    Science.gov (United States)

    Yueh, S. H.; Fore, A.; Tang, W.; Hayashi, A.

    2016-12-01

    NASA's Soil Moisture Active Passive (SMAP) mission was launched in January 2015 to provide global mapping of soil moisture. SMAP has two instruments, a polarimetric radiometer and a multi-polarization synthetic aperture radar. The radar stopped operation on 7 July 2015. Both instruments operate at L-band frequencies and share a single 6-m rotating mesh antenna, producing a fixed incidence angle conical scan at 40° across a 1000-km swath. We have analyzed all available SMAP and Aquarius data to improve the geophysical model functions, relating the L-band radar and radiometer data to ocean surface wind speed, wind direction, significant wave height and sea surface temperature. We find that it is necessary to account for the fourth order harmonics for wind direction effect and SST influence on sea surface scattering. The SMAP SSS retrieval algorithm developed at the Jet Propulsion Laboratory leverages the QuikSCAT and Aquarius algorithms to account for SMAP's two-look geometry for retrieval of SSS and wind speed. The retrieval algorithm has been applied to more than one year of SMAP radiometer data. We have also applied the Combined Active Passive (CAP) algorithm to about three months of SMAP data from April to early July 2015. The spatial patterns of the SMAP SSS agree well with climatological distributions, but exhibit several unique spatial and temporal features. The SMAP SSS reveals the temporal evolutions of freshwater plumes from several major rivers, consistent with the timing of rainy and dry seasons, indicated in the SMAP's soil moisture and Global Precipitation Missions' daily rain products. Accuracy assessment has been performed by comparison with in situ SSS data from buoys and ARGO floats. The accuracy of monthly averaged SMAP product is about 0.2 psu for tropics and mid-latitudes. The improved roughness model function has also been applied to the Aquarius data, resulting in reduction in standard deviation errors and seasonal bias at high latitudes.

  6. Phosphorus sorption-desorption and effects of temperature, pH and salinity on phosphorus sorption in marsh soils from coastal wetlands with different flooding conditions.

    Science.gov (United States)

    Bai, Junhong; Ye, Xiaofei; Jia, Jia; Zhang, Guangliang; Zhao, Qingqing; Cui, Baoshan; Liu, Xinhui

    2017-12-01

    Wetland soils act as a sink or source of phosphorus (P) to the overlaying water due to phosphorus sorption-desorption processes. Litter information is available on sorption and desorption behaviors of phosphorus in coastal wetlands with different flooding conditions. Laboratory experiments were conducted to investigate phosphorus sorption-desorption processes, fractions of adsorbed phosphorus, and the effects of salinity, pH and temperature on phosphorus sorption on soils in tidal-flooding wetlands (TW), freshwater-flooding wetlands (FW) and seasonal-flooding wetlands (SW) in the Yellow River Delta. Our results showed that the freshly adsorbed phosphorus dominantly exists in Occluded-P and Fe/AlP and their percentages increased with increasing phosphorus adsorbed. Phosphorus sorption isotherms could be better described by the modified Langmuir model than by the modified Freundlich model. A binomial equation could be properly used to describe the effects of salinity, pH, and temperature on phosphorus sorption. Phosphorus sorption generally increased with increasing salinity, pH, and temperature at lower ranges, while decreased in excess of some threshold values. The maximum phosphorus sorption capacity (Qmax) was larger for FW soils (256 mg/kg) compared with TW (218 mg/kg) and SW soils (235 mg/kg) (p water bodies through increasing P sorption. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Effect of a residue after evaporation from industrial vitamin C fermentation on chemical and microbial properties of alkali-saline soil.

    Science.gov (United States)

    Kong, Tao; Xu, Hui; Wang, Zhenyu; Sun, Hao; Wang, Lihua

    2014-07-01

    Residue after evaporation (RAE) from industrial vitamin C fermentation is emitted as a waste product at an amount of 60,000 tons per year in China. The disposal of RAE is difficult because of its high chemical oxygen demand (1.17×10(6) mg/l) and low pH (0.27). We hypothesized that RAE could be used as an ameliorant for alkali-saline soils, and tried to verify it by carrying out a pot experiment of pakchoi cultivation and to explore its effect on soil chemical and microbial properties. The results showed that pakchoi yield was increased by 28.13% and pakchoi quality was also enhanced under RAE treatment. The improved chemical and microbial properties of treated soil were also observed: soil pH was decreased from 9.19 to 9.03; total organic carbon, available phosphorus and available potassium were increased by 49.15%, 34.91% and 42.02%, respectively; number of culturable bacteria, actinomycetes and fungi, microbial biomass carbon and enzyme activity number were improved by 52.97%, 104.05%, 79.09%, 57.82% and 31.16%, respectively. These results suggested the residue application led to an improved soil quality and subsequently a higher yield and quality of pakchoi. This study provided a strong evidence for the feasibility of RAE as an ameliorant for alkali-saline soil.

  8. Water Quality and Soil Natural Salinity in the Southern Imera Basin (Sicily, Italy

    Directory of Open Access Journals (Sweden)

    Roberta Selvaggi

    2010-10-01

    Full Text Available The Southern Imera river crosses one of the most arid part of Sicily. The geochemical composition of the river water is due to the solubilization processes of gypsum rocks, which accounts for the particularly low quality of resources in the areas in which the presence of evaporitics deposits is highest. The geochemical composition and hydraulic parameters of river was monitored with the aim of reaching a better understanding of the relationships between litology and water quality. The Imera river is a potential local hydric resource, but seasonal variability of salinity does not allow farmers to use its water. A geochemical monitoring of the Imera river water has been carried out in selected localities integrating a GIS analysis of the river hydrography basin and of the distribution of the evaporitic formation. During 2003 and 2005 we performed four monitoring surveys of water chemicophysical parameters (temperature, pH and electrical conductivity and of the main ionic concentrations (Ca2+, Mg2+, K+, Na+, Cl-, SO4 2- . We also installed a multiparameter probe next to the hydrometrical station of Drasi, about 15 km from the river mouth. Such multiparameter probe was used to determine, continuously and simultaneously, temperature, electrical conductivity, pH, dissolved oxygen, redox potenzial, water level. The geochemical composition of the water allowed to confirm the results of Roda (1971 and Favara (2000, who pointed out that the main cause of degrade of the Southern Imera river are the salt-rich waters of some tributaries flowing over gypsum rocks and halite deposits. We have been able to identify which specific areas are the main contributors to the degradation of the Imera river.

  9. Effect of Microbial Inoculants on Uptake of Nutrient Elements in Two Cultivars of Sunflower (Helianthus annuus L. in Saline Soils

    Directory of Open Access Journals (Sweden)

    Mostafa SHIRMARDI

    2010-09-01

    Full Text Available A greenhouse experiment was conducted in order to evaluate the interactive effects of microbial inoculants on uptake of nutrient elements (N, P, K, Ca, Mg, Na, Cl, Fe, Zn, Cu, Mn in two cultivars of sunflower. The trials were carried out on saline (EC = 7.6 dS m-1 calcareous soils taken from Eshtehard (Karaj region of Iran. In a factorial trial and completely randomized design (CRD, three levels of arbuscular mycorrhizal inoculants (non inoculation, inoculation withGlomus etunicatum and Glomus intradices and four levels of Pseudomonas fluorescensinoculants (non inoculation and inoculation with Pseudomonas fluorescens strains 4, 9, 12 in two cultivars of sunflower with four replications per treatments were applied. Results revealed that all of the treatments increased the N uptake in Euroflor cultivar. Moreover, in Euroflor cultivar, inoculation with Pseudomonas fluorescens strains 9 and co-inoculation of Pseudomonas fluorescens strains 4 and Glomus intradices made a significant different in phosphorous uptake, while did not make any significant change in the Master cultivar. However, bacterial and fungal treatments significantly (P < 0.05 increased uptake of micro nutrients such as Fe, Zn and Mn.

  10. Effect of the salinity in the adsorption of a herbicide in agricultural soils; Efecto de la salinidad en la adsorcion de un herbicida en suelos agricolas

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez M, L. C. [Universidad de Occidente, Unidad Guasave, Departamento de Ingenieria y Tecnologia, Av. Universidad s/n, Centro, 81000 Guasave, Sinaloa (Mexico); Hansen, A. M., E-mail: ahansen@tlaloc.imta.mx [Instituto Mexicano de Tecnologia del Agua, Coordinacion de Hidrologia, Subcoordinacion de Hidrologia Subterranea, Paseo Cuauhnahuac 8532, Col. Progreso, 62550 Jiutepec, Morelos (Mexico)

    2014-10-01

    To understand the effect of salinity in the adsorption of the herbicide atrazine in two soils from a Mexican agricultural area, the influence of sodium and calcium chloride concentrations were determined. Adsorption experiments were performed with soil samples from Irrigation District 063 (Dr 063), Guasave, Sinaloa, Mexico, suspended in 10 mm CaCl{sub 2}, in the presence of several concentrations of different electrolytes and atrazine (0.01, 0.05, 0.1, 0.5 and 1.0 mg/L) with radioactive tracer (347.4 Bq U-ring-{sup 14}C, Sigma Chemical Company, St. Louis, Mo, USA). It was found that for all the electrolytes,the time required to reach equilibrium adsorption of atrazine was less than 24 h and the adsorption isotherms were adjusted to Freundlich model. The presence of sodium in the aqueous solution favored the adsorption and inhibited desorption of atrazine in soils. Increasing the concentrations of sodium and calcium to about 40 nm and 60 mm, respectively, did not significantly affect (P <0.05), the adsorption of atrazine. However, there were differences in desorption of the herbicide with the increase of salts concentrations. The results of this study indicate that increased salinity, mainly caused by increased sodium concentrations in the soil-water system, has important effects on the fate of atrazine, due to salinization of soils favors the adsorption of atrazine, and inhibits its desorption. It is important to consider these properties when application options are analyzed as well as in the management and remediation of soils contaminated with atrazine. (Author)

  11. Design of Soil Salinity Policies with Tinamit, a Flexible and Rapid Tool to Couple Stakeholder-Built System Dynamics Models with Physically-Based Models

    Science.gov (United States)

    Malard, J. J.; Baig, A. I.; Hassanzadeh, E.; Adamowski, J. F.; Tuy, H.; Melgar-Quiñonez, H.

    2016-12-01

    Model coupling is a crucial step to constructing many environmental models, as it allows for the integration of independently-built models representing different system sub-components to simulate the entire system. Model coupling has been of particular interest in combining socioeconomic System Dynamics (SD) models, whose visual interface facilitates their direct use by stakeholders, with more complex physically-based models of the environmental system. However, model coupling processes are often cumbersome and inflexible and require extensive programming knowledge, limiting their potential for continued use by stakeholders in policy design and analysis after the end of the project. Here, we present Tinamit, a flexible Python-based model-coupling software tool whose easy-to-use API and graphical user interface make the coupling of stakeholder-built SD models with physically-based models rapid, flexible and simple for users with limited to no coding knowledge. The flexibility of the system allows end users to modify the SD model as well as the linking variables between the two models themselves with no need for recoding. We use Tinamit to couple a stakeholder-built socioeconomic model of soil salinization in Pakistan with the physically-based soil salinity model SAHYSMOD. As climate extremes increase in the region, policies to slow or reverse soil salinity buildup are increasing in urgency and must take both socioeconomic and biophysical spheres into account. We use the Tinamit-coupled model to test the impact of integrated policy options (economic and regulatory incentives to farmers) on soil salinity in the region in the face of future climate change scenarios. Use of the Tinamit model allowed for rapid and flexible coupling of the two models, allowing the end user to continue making model structure and policy changes. In addition, the clear interface (in contrast to most model coupling code) makes the final coupled model easily accessible to stakeholders with

  12. Nature's patchwork: How water sources and soil salinity determine the distribution and structure of halophytic plant communities in arid environments of the Eastern Pamir.

    Science.gov (United States)

    Mętrak, Monika; Chachulski, Łukasz; Navruzshoev, Dovutsho; Pawlikowski, Paweł; Rojan, Elżbieta; Sulwiński, Marcin; Suska-Malawska, Małgorzata

    2017-01-01

    The eastern part of the Pamir Mountains, located in Central Asia, is characterized by great climatic continentality and aridity. Wetlands developed in this hostile region are restricted to spring areas, terraces of shallow lakes or floodplains along rivers, and provide diversified ecosystem services e.g. as water reservoirs, refugia for rare species and pastures for domestic cattle. These ecosystems are particularly susceptible to climate changes, that in the Pamir Mountains result in increased temperatures, intense permafrost/glacial melt and alterations of precipitation patterns. Climatic changes affect pasture management in the mountains, causing overutilization of sites located at lower elevations. Thus, both climate and man-induced disturbances may violate the existing ecological equilibrium in high-mountain wetlands of the Eastern Pamir, posing a serious risk to their biodiversity and to food security of the local population. In this context, we sought to assess how environmental drivers (with special focus on soil features and potential water sources) shape the distribution and diversity of halophytic plant communities developed in valleys in the Eastern Pamir. This task was completed by means of a vegetation survey and comprehensive analyses of habitat conditions. The lake terraces and floodplains studied were covered by a repetitive mosaic of plant communities determined by differences in soil moisture and salinity. On lower, wetter sites, this patchwork was formed by Blysmus rufus dominated salt marshes, saline small sedge meadows and saline meadows with Kobresia royleana and Primula pamirica; and on drier, elevated sites, by endemic grasslands with Hordeum brevisubulatum and Puccinellia species and patches of xerohalophytic vegetation. Continuous instability of water sources and summer droughts occurring in the Pamir Mountains may lead to significant structural and functional transformations of described wetland ecosystems. Species more tolerant to

  13. Relationships among soil properties, plant nutrition and arbuscular mycorrhizal fungi-plant symbioses in a temperate grassland along hydrologic, saline and sodic gradients.

    Science.gov (United States)

    García, Ileana V; Mendoza, Rodolfo E

    2008-03-01

    Temporal variations in the relationships among plant nutrient concentrations, soil properties and arbuscular-mycorrhizal (AM) fungal dynamics were studied along a topographic and saline gradient in a temperate grassland soil. Soil and plant (Lotus tenuis, Paspalum vaginatum, Stenotaphrum secundatum) samples were collected on four seasonally based occasions. The morphology of AM root colonization had a similar pattern in the plants studied. Maximum arbuscular colonization occurred at the beginning of the growing season in late winter and was minimal in late summer, but maximal vesicular colonization occurred in summer and was minimal in winter, suggesting a preferential production of these morphological phases by the fungus with respect to season. The greatest arbuscular colonization was associated with the highest N and P concentrations in plant tissue, suggesting a correspondence with increases in the rate of nutrient transfer between the symbiotic partners. Water content, salinity and sodicity in soil were positively associated with AM root colonization and arbuscule colonization in L. tenuis, but negatively so in the grasses. There were distinct seasonally related effects with respect to both spore density and AM colonization, which were independent of particular combinations of plant species and soil sites.

  14. High concentrations of Na+ and Cl- ions in soil solution have simultaneous detrimental effects on growth of faba bean under salinity stress.

    Science.gov (United States)

    Tavakkoli, Ehsan; Rengasamy, Pichu; McDonald, Glenn K

    2010-10-01

    Despite the fact that most plants accumulate both sodium (Na(+)) and chloride (Cl(-)) ions to high concentration in their shoot tissues when grown in saline soils, most research on salt tolerance in annual plants has focused on the toxic effects of Na(+) accumulation. There have also been some recent concerns about the ability of hydroponic systems to predict the responses of plants to salinity in soil. To address these two issues, an experiment was conducted to compare the responses to Na(+) and to Cl(-) separately in comparison with the response to NaCl in a soil-based system using two varieties of faba bean (Vicia faba), that differed in salinity tolerance. The variety Nura is a salt-sensitive variety that accumulates Na(+) and Cl(-) to high concentrations while the line 1487/7 is salt tolerant which accumulates lower concentrations of Na(+) and Cl(-). Soils were prepared which were treated with Na(+) or Cl(-) by using a combination of different Na(+) salts and Cl(-) salts, respectively, or with NaCl. While this method produced Na(+)-dominant and Cl(-)-dominant soils, it unavoidably led to changes in the availability of other anions and cations, but tissue analysis of the plants did not indicate any nutritional deficiencies or toxicities other than those targeted by the salt treatments. The growth, water use, ionic composition, photosynthesis, and chlorophyll fluorescence were measured. Both high Na(+) and high Cl(-) reduced growth of faba bean but plants were more sensitive to Cl(-) than to Na(+). The reductions in growth and photosynthesis were greater under NaCl stress and the effect was mainly additive. An important difference to previous hydroponic studies was that increasing the concentrations of NaCl in the soil increased the concentration of Cl(-) more than the concentration of Na(+). The data showed that salinity caused by high concentrations of NaCl can reduce growth by the accumulation of high concentrations of both Na(+) and Cl(-) simultaneously, but

  15. Spatial pattern formation of coastal vegetation in response to external gradients and positive feedbacks affecting soil porewater salinity: A model study

    Science.gov (United States)

    Jiang, J.; DeAngelis, D.L.; Smith, T. J.; Teh, S.Y.; Koh, H. L.

    2012-01-01

    Coastal vegetation of South Florida typically comprises salinity-tolerant mangroves bordering salinity-intolerant hardwood hammocks and fresh water marshes. Two primary ecological factors appear to influence the maintenance of mangrove/hammock ecotones against changes that might occur due to disturbances. One of these is a gradient in one or more environmental factors. The other is the action of positive feedback mechanisms, in which each vegetation community influences its local environment to favor itself, reinforcing the boundary between communities. The relative contributions of these two factors, however, can be hard to discern. A spatially explicit individual-based model of vegetation, coupled with a model of soil hydrology and salinity dynamics is presented here to simulate mangrove/hammock ecotones in the coastal margin habitats of South Florida. The model simulation results indicate that an environmental gradient of salinity, caused by tidal flux, is the key factor separating vegetation communities, while positive feedback involving the different interaction of each vegetation type with the vadose zone salinity increases the sharpness of boundaries, and maintains the ecological resilience of mangrove/hammock ecotones against small disturbances. Investigation of effects of precipitation on positive feedback indicates that the dry season, with its low precipitation, is the period of strongest positive feedback. ?? 2011 Springer Science+Business Media B.V. (outside the USA).

  16. Streptomyces fukangensis sp. nov., a novel alkaliphilic actinomycete isolated from a saline-alkaline soil.

    Science.gov (United States)

    Zhang, Yong-Guang; Wang, Hong-Fei; Liu, Qing; Hozzein, Wael N; Wadaan, Mohammed A M; Cheng, Juan; Chen, Yue-Ji; Zhang, Yuan-Ming; Li, Wen-Jun

    2013-12-01

    An alkaliphilic actinobacterium, designated EGI 80050(T), was isolated from a desert soil sample of Xinjiang, north-west China, and characterized by a polyphasic approach. The isolate was observed to produce purple orange-yellow aerial mycelium and dark orange-yellow substrate mycelium on yeast extract-malt extract agar medium. Whole-cell hydrolysates of strain EGI 80050(T) were found to contain LL-diaminopimelic acid as the diagnostic diamino acid, and galactose, glucose, rhamnose and mannose as the main sugars. The major fatty acids identified were C16:0-iso (36.8 %), C15:0-anteiso (17.3 %), 15:0-iso (13.2 %) and 14:0-iso (10.5 %). The predominant menaquinones detected were MK-9(H6) and MK-9(H8), while the characteristic polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides, phosphatidylmethylethanolamine and three unknown phospholipids. The G+C content of the genomic DNA was determined to be 67.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences affiliated the strain EGI 80050(T) to the genus Streptomyces. Levels of 16 rRNA gene sequence similarities between strain EGI 80050(T) and Streptomyces candidus NRRL ISP-5141(T), Streptomyces cremeus NBRC 12760(T), Streptomyces spiroverticillatus NBRC 12821(T), Streptomyces violaceorectus NBRC 13102(T), Streptomyces cinereoruber subsp. cinereoruber NBRC 12756(T) were 96.7, 96.6, 96.6, 96.6 and 96.6 %, respectively. Based on the phenotypic, chemotaxonomic and phylogenetic data, strain EGI 80050(T) is considered to represent a novel species of the genus Streptomyces, for which the name Streptomyces fukangensis sp. nov. (type strain EGI 80050(T) = BCRC 16945(T) = JCM 19127(T)) is proposed.

  17. Nocardia halotolerans sp. nov., a halotolerant actinomycete isolated from saline soil.

    Science.gov (United States)

    Moshtaghi Nikou, Mahdi; Ramezani, Mohaddaseh; Ali Amoozegar, Mohammad; Rasooli, Mehrnoosh; Harirchi, Sharareh; Shahzadeh Fazeli, Seyed Abolhasan; Schumann, Peter; Spröer, Cathrin; Ventosa, Antonio

    2015-09-01

    A novel halotolerant actinomycete, strain Chem15(T), was isolated from soil around Inche-Broun hypersaline wetland; its taxonomic position was determined based on a polyphasic approach. Strain Chem15(T) was strictly aerobic and tolerated NaCl up to 12.5%. The optimum temperature and pH for growth were 28-30 °C and pH 7.0-7.5, respectively. The cell wall of strain Chem15(T) contained meso-diaminopimelic acid as diamino acid and galactose, arabinose and ribose as whole-cell sugars. The major phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides. The cellular fatty acids profile consisted of C16 : 0, iso-C18 : 0, C18 : 0 10-methyl and C18 : 1ω9c, and the major respiratory quinone was MK-8(H4cycl). The G+C content of the genomic DNA was 68.0 mol%. The novel strain constituted a distinct phyletic line within the genus Nocardia, based on 16S rRNA gene sequence analysis, and was closely associated with Nocardia sungurluensis DSM 45714(T) and Nocardia alba DSM 44684(T) (98.2 and 98.1% 16S rRNA gene sequence similarity, respectively). However DNA-DNA relatedness and phenotypic data demonstrated that strain Chem15(T) was clearly different from closely related species of the genus Nocardia. It is concluded that the organism should be classified as a representative of a novel species of the genus Nocardia, for which the name Nocardia halotolerans sp. nov. is proposed. The type strain is Chem15(T) ( = IBRC-M 10490(T) = LMG 28544(T)).

  18. The Effects of Zinc and Iron Oxide Nano-Particles on The Growth and Ion Content of Two Corn Cultivars in Different Soil Salinity

    Directory of Open Access Journals (Sweden)

    2014-07-01

    Full Text Available This study was conducted in order to evaluate the effects of foliar application of nano-particles and ordinary bulk materials of zinc and iron oxide was studied in two corn genotypes (S.C 704 and seed mass in different soil salinity (0,75,150 mM NaCl. The experiment was arranged as factorial in a randomized complete block design with four replications. The results showed that in saline condition Leaf area, shoot and root dry matter, photochemical efficiency, the concentration of K, Fe and Zn in shoot decreased and that of Na and the Na/K ratio increased under saline condition. The interactions of salinity and genotype were significant on leaf area, shoot and root dry matter, Na/K ratio and photochemical efficiency. The application of nano-particles of iron and zinc oxide increased shoot dry matter to a greater degree as compared with ordinary bulk materials. Under saline condition, the application of iron oxide in the form of nano-particles had higher effect on iron uptake by corn plants. However, with an increase in salinity level the superiority of nano form decreased. The application of Nano-particles of iron and zinc as compared to ordinary bulk materials was more effective in alleviating the negative effects of salt stress on the accumulation of zinc in tested plants. This was not evidence in terms of iron accumulation. The results from this experiment showed that the application of nano-particles of iron and zinc promoted plant growth to a greater degree in comparison to ordinary materials of these nutrients. However, the application of nano particles had no advantage in alleviating the effects of salinity on plant growth.

  19. Controlo da salinidade do solo com recurso à sementeira directa Control of the soil salinity by using direct drilling

    Directory of Open Access Journals (Sweden)

    J. P. Mendes

    2009-01-01

    mais baixos de condutividade eléctrica da solução do solo ao fim de dois anos são indicadores, de que, a sementeira directa, em conjunto com uma cultura de cobertura, poderá ser uma ferramenta útil na prática de uma agricultura de regadio sustentável, em clima semi-árido e em solos de baixa condutividade hidráulica, mesmo utilizando águas de rega com condutividade eléctrica (CE moderada.The use of water with moderated salt content for irrigation under semi-arid conditions, especially on soils with low saturated hydraulic conductivity, can lead to an increase of the salt content of the soil and even to an increase of exchangeable Na. This is a possible scenario in the Alqueva irrigation program in the South of Portugal. The present study aims to evaluate the potential of direct drilling and soil mulching as a way to improve infiltration and reduce evaporation, in order to reduce salt accumulation during the summer and to improve leaching during the winter. The trial has been carried out on a Calcic Luvisols (FAO classification under centre pivot irrigation. There were used two soil tillage treatments (direct drilling and traditional - chisel plow plus two disc arrows, two levels of water salinity (0.7 dS m-1 and 2 dS m-1 and two water regimes (100% and 70% of Etc. The experimental design is a split plot, with tillage as the reference treatment. After the second year the salinity in the top 0.20 m of the soil is lower under direct drilling (0.63 dS m-1 than under traditional tillage system (0.75 dS m-1. The differences between tillage treatments are more evident for the higher water regime. The lowest values of electric conductivity in soil solution at the end of two years, indicate that direct drilling together with cover crop, can be a useful tool in irrigation under semi-arid conditions, in soils with low values of hydraulic conductivity, even when using water with moderated electrical conductivity (EC.

  20. Seed priming and sulfur effects on soybean cell membrane stability and yield in saline soil Condicionamento osmótico das sementes e disponibilidade de enxofre na estabilidade da membrana celular e produtividade de soja em solo salino

    National Research Council Canada - National Science Library

    Teymur Khandan Bejandi; Mohammad Sedghi; Raouf Seyed Sharifi; Ali Namvar; Peyman Molaei

    2009-01-01

    The objective of this work was to determine the effects of seed priming and sulfur application on cell membrane characteristics, seedling emergence, chlorophyll content and grain yield of soybean (Glycine max) in saline soil...

  1. Salinity: Electrical conductivity and total dissolved solids

    Science.gov (United States)

    The measurement of soil salinity is a quantification of the total salts present in the liquid portion of the soil. Soil salinity is important in agriculture because salinity reduces crop yields by reducing the osmotic potential making it more difficult for the plant to extract water, by causing spe...

  2. Contribution of electromagnetic and tomographic technique to the study of the impact of salinity in soils of the experimental station of Al Ain Atti (Errachidia, Morocco)

    Science.gov (United States)

    Benamara, A.; El Harnafi, M.; Ammar, A.

    2017-03-01

    Soil salinity is widespread particularly in arid areas. Much work has been done to remedy this natural contamination and make them more favorable to receive experimental soil of vegetation adapted to grow in these contrasting environments of scarce water resources. Over the 80 years, Morocco has experienced excessive dryness whose effects have been severely felt in the region of Errachidia. The depletion of the Quaternary alluvial aquifer has required the exploitation of deep reservoirs. In order to optimize the use of salt water in arid, the Institute of Agricultural Research tested soil experimenting three plant species; the Triplex, Acacia and Cypress. This experiment was not only economic objectives; increasing agricultural yields and production, but also reduce the impact of desertification in this region. So these are environmental reasons which have led researchers to realize this experiment whose purpose is to examine the ability of these plants to grow and adapt to irrigation by saline water from the deep aquifer in place. The experimental site is located on the left bank of the national road to Erfoud (Errachidia). In its entirety, the redesigned covering about 10 hectares. The studies that have been conducted mainly concerned pedogenetic analyzes and observations the development height of the plantation tested, regardless of the experimental ground heterogeneity. This is why we undertook a geophysical survey which aims to provide information on the quality of the tested soils and accumulation of salinity at different depths of the experimental ground. To achieve our goal, we used the technique of electrical and electromagnetic investigation in order to identify the main lines of a possible spatial heterogeneity. Recall that the work of OKAY (2010) on an experiment coring by examining the evolution of the newly formed fracturing have proved that the result of resistivity measurement is correlated with that of the chargeability. The electrical resistivity

  3. Tolerância da cultura do tomate à salinidade do solo em ambiente protegido Tolerance of tomato crop to salinity of soil in protected ambient

    Directory of Open Access Journals (Sweden)

    Pedro R. F. Medeiros

    2012-01-01

    Full Text Available Com o intuito de contribuir com os dados disponíveis na literatura sobre tolerância das culturas à salinidade do solo oriunda de sais fertilizantes, o presente trabalho tem, como objetivo, determinar a tolerância da cultura do tomate a salinidade do solo, a partir de dois manejos de fertirrigação e seis níveis iniciais de salinidade (1,0; 2,0; 3,0; 4,0; 5,0 e 6,0 dS m-1 a partir das variáveis produção e componentes de produção, em ambiente protegido com solo franco-argiloso. O experimento foi realizado no Departamento de Engenharia de Biossistemas da ESALQ/USP, Piracicaba,SP. O delineamento estatístico foi aleatorizado em blocos, com 4 repetições, concluindo que a produção e os componentes de produção da cultura do tomate foram afetados estatisticamente, tanto pelo tipo de manejo de fertirrigação quanto pelos níveis de salinidade do solo, com redução na tolerância da cultura do tomate, passando a ser classificada sensível à salinidade do solo.In order to contribute to data available in the literature on tolerance of crops to soil salinity derived from fertilizer salts, the present study aims to determine the tolerance of tomato crop to the soil salinity, based on two managements of fertirrigation and six initial levels of salinity (1.0; 2.0; 3.0; 4.0; 5.0 and 6.0 dS m-1 from the variables production and components of production, in a protected environment with sandy-clay soil. The experiment was conducted at the Department of Biosystems Engineering of ESALQ/USP, Piracicaba/SP. The experimental design was in randomized blocks, with 4 repetitions. Concluding that the production and the components of production of tomato crop were significantly affected both by the type of management of fertirrigation and by the levels of soil salinity, with a reduction in the tolerance of tomato crop, being classified as sensitive to soil salinity.

  4. The Effects of Salinity and Sodium Adsorption Ratio on the Water Retention and Hydraulic Conductivity Curves of Soils From The Pampa del Tamarugal, Chile

    Science.gov (United States)

    Lagos, M. S.; Munoz, J.; Suarez, F. I.; Fierro, V.; Moreno, C.

    2015-12-01

    The Pampa del Tamarugal is located in the Atacama Desert, the most arid desert of the world. It has important reserves of groundwater, which are probably fed by infiltration coming from the Andes Mountain, with groundwater levels fluctuating between 3 and 10-70 m below the land surface. In zones where shallow groundwater exists, the capillary rise allows to have a permanently moist vadose zone, which sustain native vegetation such as the Tamarugos (Prosopis tamarugo Phil.) and Algarrobos (Prosopis alba Griseb.). The native vegetation relies on the soil moisture and on the evaporative fluxes, which are controlled by the hydrodynamic characteristics of the soils. The soils associated to the salt flats of the Pampa del Tamarugal are a mixture of sands and clays, which have high levels of sulfates, chloride, carbonates, sodium, calcium, magnesium, and potassium, with high pH and electrical conductivity, and low organic matter and cationic exchange capacity. In this research, we are interested in evaluating the impact of salinity and sodium adsorption ratio (SAR) on the hydrodynamic characteristics of the soil, i.e., water retention and hydraulic conductivity curves. Soils were collected from the Pampa del Tamarugal and brought to the laboratory for characterization. The evaporation method (HYPROP, UMS) was used to determine the water retention curve and the hydraulic conductivity curve was estimated combining the evaporation method with direct measurements using a variable head permeameter (KSAT, UMS). It was found that higher sodium concentrations increase the water retention capacity and decrease the soiĺs hydraulic conductivity. These changes occur in the moist range of the hydrodynamic characteristics. The soil's hydraulic properties have significant impact on evaporation fluxes, which is the mayor component of the water balance. Thus, it is important to quantify them and incorporate salt precipitation/dissolution effect on the hydrodynamic properties to correctly

  5. Incorporação de gesso para correção da salinidade e sodicidade de solos salino-sódicos Incorporation of gypsum to correct the salinity and sodicity of saline-sodic soils

    Directory of Open Access Journals (Sweden)

    Antonio N. Tavares Filho

    2012-01-01

    Full Text Available Com o objetivo de avaliar o efeito da aplicação do gesso nas características químicas de solos salino-sódicos coletados no Perímetro Irrigado do Moxotó, localizado no município de Ibimirim, PE, um experimento foi realizado em colunas de solo instaladas no Laboratório de Mecânica do Solo e Aproveitamento de Resíduo da Universidade Federal Rural de Pernambuco. Os tratamentos foram dispostos em um delineamento inteiramente casualizado com esquema fatorial de dois solos (S1 e S2 e sete níveis da necessidade de gesso (50, 75, 100, 125, 150, 175 e 200% determinado pelo Método de Laboratório Schoonover-M1. O gesso foi incorporado aos solos, em três repetições, totalizando 42 unidades experimentais. As variáveis avaliadas foram: i condutividade elétrica (CE, ii cátions solúveis e iii relação de adsorção de sódio (RAS no extrato de saturação do solo. O nível de 100% da necessidade de gesso causou diminuição da sodicidade para valores de RAS Aiming to evaluate the effect of gypsum on the modification of chemical properties of saline-sodic soils collected in the Irrigated Perimeter of Ibimirim-PE, an experiment was carried out in soil columns installed at the Soil Mechanics and Residue Recovery Laboratoy at the Universidade Federal Rural de Pernambuco. The treatments were arranged in a completely randomized design with factorial arrangement of two soils (S1 and S2 and seven levels of gypsum requirement (50, 75, 100, 125, 150, 175 and 200% determined by the Laboratory Method Schoonover-M1. The gypsum was incorporated in to the soils, in three replications, totaling 42 experimental units. The parameters evaluated were: electrical conductivity (EC, soluble cations and sodium adsorption ratio (SAR in the saturation extract of soil. The level of the 100% of gypsum requirement caused decreased in sodicity values of SAR under 13 (mmol L-1½, presenting itself as an effective method in reducing the levels of sodium in areas affected

  6. Fates of salinity and nitrogen in soil and shallow groundwater under long-term reclaimed water irrigation

    Science.gov (United States)

    Lyu, S.; Chen, W.

    2016-12-01

    Reclaimed water as an alternative water resource has been extensively employed for irrigation. Assessment of groundwater quality is of great concern owing to salt and nitrogen leaching under reclaimed water irrigation. Field investigations were conducted in the shallow groundwater monitoring well of Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, and sample sites with growing turf grasses were irrigated by reclaimed water for 9 years. The HYDRUS model and MODFLOW model were coupled to study the transport and distribution of electrical conductivity (ECgw) and nitrate-N (NO3-) in soil and shallow groundwater under long-term reclaimed water irrigation. The results of model calibration and validation showed that the coupled model could simulate the ECgw (RMSE ≤ 0.04 dS/m) and NO3- (RMSE ≤ 0.29 mg/L) in shallow groundwater well. Under long-term reclaimed water irrigation based on the annual average irrigation conditions, average ECgw increased from 0.572 to 0.715 dS/m, and average NO3- decreased from 9.31 to 7.54 mg/L because of initial concentration was high when equilibrium state was reached. Under irrigation water salinity of 0.6, 1.2 and 2.4 dS/m, simulated annually average ECgw increased to 0.698, 0.759 and 0.866 dS/m respectively at the equilibrium state. As the increasing of irrigation amount, ECgw in shallow groundwater increased. Annually average NO3- increased also slightly with the increasing of irrigation water nitrogen concentration and water amount. Above all, ECgw and NO3- in shallow groundwater under these simulation scenarios will not exceed the quality standard for groundwater in China. It is not recommended to use water-saving irrigation considering the factors of ECgw and NO3- in shallow groundwater under reclaimed water irrigation in Beijing.

  7. Varying evapotranspiration and salinity level of irrigation water influence soil quality and performance of perennial ryegrass (lolium perenne l.)

    Science.gov (United States)

    Increasing use of recycled water that is often high in salinity warrants further examination of irrigation practices for turfgrass health and salinity management. A study was conducted during 2011-2012 in Riverside, CA to evaluate the response of perennial ryegrass (Lolium perenne L.) ‘SR 4550’ turf...

  8. Evaluation of the halophyte Salsola soda as an alternative crop for saline soils high in selenium and boron

    Science.gov (United States)

    Salinization is one important factor contributing to land degradation, which affects agricultural production and environmental quality, especially in the West side of central California. When salinization is combined with a natural contamination of trace elements (i.e., Se and B) in arid and semi-ar...

  9. Simulation of Zinc Release Affected by Microbial Inoculation and Salinity Levels in a non-sterile Calcareous Soil Using kinetic Models

    Directory of Open Access Journals (Sweden)

    hamidreza boostani

    2017-02-01

    Full Text Available Introduction: Zinc (Zn is an important nutrient element for humans and plants that controls many biochemical and physiological functions of living organisms. Zinc deficiency is common in high pH, low organic matter, carbonatic, saline and sodic soils. Salinity is a major abiotic environmental stresses that limits growth and production in arid and semi-arid regions of the world. Bioavailability of Zn is low in calcareous and saline soils having high levels of pH and calcium. Desorption of Zinc (Zn from soil as influenced by biological activities is one of the important factors that control Zn bioavailability. Few reports on the effects of salinity on the availability and desorption kinetics of Zn are available. Rupa et al. (2000 reported that increasing the salt concentration led to increase Zn desorption from soil due to ion competition on soil exchangeable sites. Different kinetic equations have been used to describe the release kinetics of nutrients. Reyhanitabar and Gilkes (2010 found that the power function model was the best equation to describe the release of Zn from some calcareous soil of Iran, whereas Baranimotlagh and Gholami (2013 stated that the best model for describing Zn desorption from 15 calcareous soils of Iran was the first-order equation.less attention has been paid to kinetics of Zn release by DTPA extractant over time by inoculation of plant growth promoting rhizobacteria and mycorrhizae fungi in comination with soil salinity.The objective of this study was to evaluate the effect of plant growth promoting rhizobacteria (PGPR and mycorrhizae fungi (MF inoculation on release kinetic of Zn in a calcareous soil at different salinity levels after in cornplantation Materials and Methods: A composite sample of bulk soil from the surface horizon (0-30 cm of a calcareous soil from southern part of Iran was collected, air dried, passed through 2 mm sieve, and thoroughly mixed. Routine soil analysis was performed to determine some

  10. of integrated application of farmyard manure, plant growth promoting rhizobacteria and chemical fertilizers on production of canola (Brassica napus L. in saline soil of Qum

    Directory of Open Access Journals (Sweden)

    H. Sabahi

    2016-04-01

    Full Text Available Canola (Brassica napus L. is one of the most important oil seed crops. In order to evaluate the effects of integrated fertilization (chemical, manure and biofertilizers on canola (B. napus variety Hyola 401 yield and uptake of mineral nutrients in saline soil and water, a field experiment was conducted in randomized complete blocks (RCBD arrangement with eight treatments in three replications in Qum Province, Iran. Treatments were: (1 Control, P%100 (Phosphorus %100, (2 P%75B1 (Phosphorus %75+ Barvar biofertilizer, (3 P%75B2 (Phosphorus %75+ Nitroxin biofertilizer, (4 P%75M (Phosphorus %75+ farmyard manure, (5 P%75B1M (Phosphorus %75+ Barvar + Farmyard manure, (6 P%75B2M (Phosphorus %75+ Nitroxin+ Farmyard manure, (7 P%100B1 (Phosphorus %100 + Barvar and (8 P%125B2 (Phosphorus %125+ Nitroxin. The results showed that the highest yield was obtained from P%75B1M. Difference between integrated fertilization of farmyard manure and other treatments was significant. Farmyard manure increased canola yield which was attributed to increase in availability of mineral nutrients, decreasing effects of salinity and toxic ions. Integrated application of 5 t. ha-1 of farmyard manure and %75 recommended chemical P increased yield and decreased fertilizer consumption. The results revealed that integrated applications of farmyard manure and chemical fertilizer and after that integrated use of bio- and chemical fertilizer are the best strategies to increase nutrient availability and improving canola yield in saline soil.

  11. Application of AM Fungi with Bradyrhizobium japonicum in improving growth, nutrient uptake and yield of Vigna radiata L. under saline soil

    Directory of Open Access Journals (Sweden)

    Nisha Kadian

    2014-08-01

    Full Text Available A pot experiment was conducted under polyhouse conditions, to evaluate the effect of two different arbuscular mycorrhizal fungi (G. mosseae and A. laevis in combination with Bradyrhizobium japonicum on growth and nutrition of mungbean plant grown under different salt stress levels (4 dS m−1, 8dS m−1 and 12 dS m−1. It was found that under saline conditions, mycorrhizal fungi protect the host plant against the detrimental effect of salinity. The AM inoculated plants showed positive effects on plant growth, dry biomass production, chlorophyll content, mineral uptake, electrolyte leakage, proline, protein content and yield of mungbean plants in comparison to non-mycorrhizal ones but the extent of response varied with the increasing level of salinity. In general, the reduction in Na uptake along with associated increase in P, N, K, electrolyte leakage and high proline content were also found to be better in inoculated ones. The overall results demonstrate that the co-inoculation of microbes with AM fungi promotes salinity tolerance by enhancing nutrient acquisition especially phosphorus (P, producing plant growth hormones, improving rhizospheric and condition of soil by altering the physiological and biochemical properties of the mungbean plant.

  12. Evaluation of Geostatistical Techniques for Mapping Spatial Distribution of Soil PH, Salinity and Plant Cover Affected by Environmental Factors in Southern Iran

    Directory of Open Access Journals (Sweden)

    Mohammad ZARE-MEHRJARDI

    2010-12-01

    Full Text Available The study presented in this paper attempts to evaluate some interpolation techniques for mapping spatial distribution of soil pH, salinity and plant cover in Hormozgan province, Iran. The relationships among environmental factors and distribution of vegetation types were also investigated. Plot sampling was applied in the study area. Landform parameters of each plot were recorded and canopy cover percentages of each species were measured while stoniness and browsing damage were estimated. Results indicated that there was a significant difference in vegetation cover for high and low slope steepness. Also, vegetation cover was greater than other cases in the mountains with calcareous lithology. In general, there were no significant relationships among vegetation cover and soil properties such as pH, EC, and texture. Other soil properties, such as soil depth and gravel percentage were significantly affected by vegetation cover. Moreover, the geostatistical results showed that kriging and cokriging methods were better than inverse distance weighting (IDW method for prediction of the spatial distribution of soil properties. Also, the results indicated that all the concerned soil and plant parameters were better determined by means of a cokriging method. Land elevation, which was highly correlated with studied parameters, was used as an auxiliary parameter.

  13. Crescimento inicial do cafeeiro irrigado com água salina e salinização do solo Initial growth of coffee plants irrigated with saline water and soil salinization

    Directory of Open Access Journals (Sweden)

    Vladimir B. Figueirêdo

    2006-03-01

    Full Text Available A cultura do cafeeiro (Coffea arabica L. vem-se expandindo para regiões ainda pouco exploradas, em que o uso da irrigação com água salina possa ser fator limitante. Nesse contexto, avaliou-se o crescimento inicial do cafeeiro, conduzido em casa de vegetação do Departamento de Engenharia da Universidade Federal de Lavras (UFLA, submetendo-o a níveis crescentes de salinidade da água de irrigação. O delineamento utilizado foi inteiramente casualizado com 6 tratamentos (S0 = 0,0 dS m-1, S1 = 0,6 dS m-1, S2 = 1,2 dS m-1, S3 = 1,8 dS m-1, S4 = 2,4 dS m-1 e S5 = 3,0 dS m-1 e 4 repetições. A reposição de água foi realizada com base na curva característica do solo, pela leitura da tensão de água por blocos de resistência, retornando o conteúdo de água à capacidade de campo. Verificou-se que os tratamentos influenciaram significativamente as características da planta e que a salinidade da água a partir de 1,2 dS m-1 prejudicou o crescimento e, em alguns casos, provocou a morte das plantas. A área foliar foi a variável mais prejudicada. Ao final do experimento o solo foi classificado como salino-sódico.The coffee crop is expanding to new areas with not enough studies about its response to saline irrigation water. The initial growth of coffee plant was evaluated, in greenhouse at the Engineering Department of the Federal University of Lavras (UFLA, under different levels of irrigation water salinity. The completely randomized design was used with 6 treatments (S0 = 0.0 dS m-1, S1 = 0.6 dS m-1, S2 = 1.2 dS m-1, S3 = 1.8 dS m-1, S4 = 2.4 dS m-1 and S5 = 3.0 dS m-1 and 4 replications. The irrigation was accomplished according to soil water retention curve and resistance block reading, restoring the soil water content to its field capacity. It was verified that water salinity affected the plants characteristics significantly. The water salinity above 1.2 dS m-1 caused damage to plant development resulting, in some cases, in death of

  14. Performances of the Electrical Spectroscopy employing a RESPER Probe for measuring the Salinity and Water Content of Concretes and Terrestrial Soils

    CERN Document Server

    Settimi, A; Zirizzotti, A; Marchetti, M; Sapia, V

    2010-01-01

    This paper proposes to discuss the performances of the electrical spectroscopy employing a RESPER probe to measure the salinity s and volumetric content {\\theta}W of water in concretes and terrestrial soils. The RESPER probe is an induction device for spectroscopy which performs simultaneous and non invasive measurements on the electrical RESistivity 1/{\\sigma} and relative dielectric PERmittivity {\\epsilon}r of a subjacent medium. The RESPER measures {\\sigma} and {\\epsilon} with inaccuracies below a prefixed limit (10%) in the band of middle and high frequencies (MF-HF). The conductivity is related to salinity and the dielectric permittivity to volumetric water content by suitable refined theoretical models which are consistent with the predictions of two empirical laws, respectively Archie's and Topp's. The better agreement, the lower the hygroscopic water content and the higher s; so a better agreement occurs for concretes, containing almost no bound water molecules, provided that are characterized by an h...

  15. A Compact L-band Radiometer for High Resolution sUAS-based Imaging of Soil Moisture and Surface Salinity Variations

    Science.gov (United States)

    Gasiewski, A. J.; Stachura, M.; Dai, E.; Elston, J.; McIntyre, E.; Leuski, V.

    2014-12-01

    Due to the long electrical wavelengths required along with practical aperture size limitations the scaling of passive microwave remote sensing of soil moisture and salinity from spaceborne low-resolution (~10-100 km) applications to high resolution (~10-1000 m) applications requires use of low flying aerial vehicles. This presentation summarizes the status of a project to develop a commercial small Unmanned Aerial System (sUAS) hosting a microwave radiometer for mapping of soil moisture in precision agriculture and sea surface salinity studies. The project is based on the Tempest electric-powered UAS and a compact L-band (1400-1427 MHz) radiometer developed specifically for extremely small and lightweight aerial platforms or man-portable, tractor, or tower-based applications. Notable in this combination are a highly integrated sUAS/radiometer antenna design and use of both the upwelling emitted signal from the surface and downwelling cold space signal for precise calibration using a unique lobe-differencing correlating radiometer architecture. The system achieves a spatial resolution comparable to the altitude of the UAS above the surface while referencing upwelling measurements to the constant and well-known background temperature of cold space. The radiometer has been tested using analog correlation detection, although future builds will include infrared, near-infrared, and visible (red) sensors for surface temperature and vegetation biomass correction and digital sampling for radio frequency interference mitigation. This NASA-sponsored project is being developed for commercial application in cropland water management (for example, high-value shallow root-zone crops), landslide risk assessment, NASA SMAP satellite validation, and NASA Aquarius salinity stratification studies. The system will ultimately be capable of observing salinity events caused by coastal glacier and estuary fresh water outflow plumes and open ocean rainfall events.

  16. Effect of NaCl salinity and soil waterlogging on growth characteristics of forage corn in greenhouse conditions

    OpenAIRE

    N. Najafi; E. Sarhangzadeh

    2012-01-01

    Salinity and waterlogging are two important abiotic stresses to plants growth and yield in the world. These two stresses can occur simultaneously and have additive effects on plants, including corn, growth. In a greenhouse experiment, the effects of NaCl salinity and waterlogging and their interactive effect on the growth characteristics of forage corn (Zea mays cv. single cross 704) were studied. A factorial experiment on the basis of completely randomized design with three replications was ...

  17. Long-term effect of agricultural reclamation on soil chemical properties of a coastal saline marsh in Bohai Rim, northern China.

    Science.gov (United States)

    Wang, Yidong; Wang, Zhong-Liang; Feng, Xiaoping; Guo, Changcheng; Chen, Qing

    2014-01-01

    Over the past six decades, coastal wetlands in China have experienced rapid and extensive agricultural reclamation. In the context of saline conditions, long-term effect of cultivation after reclamation on soil chemical properties has not been well understood. We studied this issue using a case of approximately 60-years cultivation of a coastal saline marsh in Bohai Rim, northern China. The results showed that long-term reclamation significantly decreased soil organic carbon (SOC) (-42.2%) and total nitrogen (TN) (-25.8%) at surface layer (0-30 cm) as well as their stratification ratios (SRs) (0-5 cm:50-70 cm and 5-10 cm:50-70 cm). However, there was no significant change in total phosphorus (TP) as well as its SRs under cultivation. Cultivation markedly reduced ratios of SOC to TN, SOC to TP and TN to TP at surface layer (0-30 cm) and their SRs (0-5 cm:50-70 cm). After cultivation, electrical conductivity and salinity significantly decreased by 60.1% and 55.3% at 0-100 cm layer, respectively, suggesting a great desalinization. In contrast, soil pH at 20-70 cm horizons notably increased as an effect of reclamation. Cultivation also changed compositions of cations at 0-10 cm layer and anions at 5-100 cm layer, mainly decreasing the proportion of Na+, Cl- and SO4(2-). Furthermore, cultivation significantly reduced the sodium adsorption ratio and exchangeable sodium percentage in plow-layer (0-20 cm) but not residual sodium carbonate, suggesting a reduction in sodium harm.

  18. Growth, tolerance efficiency and phytoremediation potential of Ricinus communis (L.) and Brassica juncea (L.) in salinity and drought affected cadmium contaminated soil.

    Science.gov (United States)

    Bauddh, Kuldeep; Singh, Rana P

    2012-11-01

    We have previously reported that Ricinus communis (castor) is more tolerant to soil cadmium (Cd) and more efficient for Cd phytoremediation than Brassica juncea (Indian mustard) (Bauddh and Singh, 2012). In the present study, R. communis was found more tolerant to salinity and drought in presence of Cd and removed more Cd in a given time than Indian mustard. R. communis produced 23 and twelve folds higher biomass in terms of fresh weight and dry weight, respectively than that in B. juncea during three months when grown in Cd contaminated soil in presence of 100mM NaCl salinity and ten day water withdrawal based drought at 90 day after sowing (DAS). Castor plants showed stronger self-protection ability in form of proline bioaccumulation (r(2)=0.949) than Indian mustard (r(2)=0.932), whereas a lower r(2) for malondialdehyde (MDA) and total soluble protein in R. communis (r(2)=0.914 and r(2)=0.915, respectively) than that of B. juncea (r(2)=0.947 and r(2)=0.927, respectively) indicated a greater damage to cell membrane in Indian mustard during the multiple stress conditions. Though, the amount of Cd accumulated in the roots and shoots of Indian mustard was higher as per unit biomass than that in castor, total removal of the metal from soil was much higher in castor on per plant basis in the same period in presence of the stresses. R. communis accumulated about seventeen and 1.5 fold higher Cd in their roots and shoots, respectively than that of B. juncea in 90 DAS under the multiple stresses. Salinity alone enhanced Cd uptake, whereas drought stress reduced its uptake in both the plants. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Long-Term Effect of Agricultural Reclamation on Soil Chemical Properties of a Coastal Saline Marsh in Bohai Rim, Northern China

    Science.gov (United States)

    Wang, Yidong; Wang, Zhong-Liang; Feng, Xiaoping; Guo, Changcheng; Chen, Qing

    2014-01-01

    Over the past six decades, coastal wetlands in China have experienced rapid and extensive agricultural reclamation. In the context of saline conditions, long-term effect of cultivation after reclamation on soil chemical properties has not been well understood. We studied this issue using a case of approximately 60-years cultivation of a coastal saline marsh in Bohai Rim, northern China. The results showed that long-term reclamation significantly decreased soil organic carbon (SOC) (−42.2%) and total nitrogen (TN) (−25.8%) at surface layer (0–30 cm) as well as their stratification ratios (SRs) (0–5 cm:50–70 cm and 5–10 cm:50–70 cm). However, there was no significant change in total phosphorus (TP) as well as its SRs under cultivation. Cultivation markedly reduced ratios of SOC to TN, SOC to TP and TN to TP at surface layer (0–30 cm) and their SRs (0–5 cm:50–70 cm). After cultivation, electrical conductivity and salinity significantly decreased by 60.1% and 55.3% at 0–100 cm layer, respectively, suggesting a great desalinization. In contrast, soil pH at 20–70 cm horizons notably increased as an effect of reclamation. Cultivation also changed compositions of cations at 0–10 cm layer and anions at 5–100 cm layer, mainly decreasing the proportion of Na+, Cl− and SO42−. Furthermore, cultivation significantly reduced the sodium adsorption ratio and exchangeable sodium percentage in plow-layer (0–20 cm) but not residual sodium carbonate, suggesting a reduction in sodium harm. PMID:24695526

  20. Morphogenesis of a saline soil ciliate Urosoma salmastra (Dragesco and Dragesco-Kernéis, 1986) Berger, 1999 with notes on the phylogeny of Urosoma (Ciliophora, Hypotrichia).

    Science.gov (United States)

    Wang, Jingyi; Qi, Shuyan; Chen, Lingyun; Warren, Alan; Miao, Miao; Shao, Chen

    2017-10-01

    Morphogenesis in a population of Urosoma salmastra collected from saline soil in Weinan, China, was investigated using protargol staining. The main morphogenetic event that characterizes U. salmastra is the inclusion of cirrus III/2 in the formation of the frontoventra-transverse cirral anlagen. We also provide small subunit ribosomal DNA gene sequences for a population of U. salmastra and for two populations of U. emarginata. The molecular phylogeny indicates that Urosoma is not monophyletic, viz, U. emarginata branches separately from its congeners and the closest relative of U. salmastra is Oxytricha granulifera. Copyright © 2017 Elsevier GmbH. All rights reserved.

  1. Biochar-manure compost in conjunction with pyroligneous solution alleviated salt stress and improved leaf bioactivity of maize in a saline soil from central China: a 2-year field experiment.

    Science.gov (United States)

    Lashari, Muhammad Siddique; Ye, Yingxin; Ji, Haishi; Li, Lianqing; Kibue, Grace Wanjiru; Lu, Haifei; Zheng, Jufeng; Pan, Genxing

    2015-04-01

    Salinity is a major stress threatening crop production in dry lands. A 2-year field experiment was conducted to assess the potential of a biochar product to alleviate salt-stress to a maize crop in a saline soil. The soil was amended with a compost at 12 t ha(-1) of wheat straw biochar and poultry manure compost (BPC), and a diluted pyroligneous solution (PS) at 0.15 t ha(-1) (BPC-PS). Changes in soil salinity and plant performance, leaf bioactivity were examined in the first (BPC-PS1) and second (BPC-PS2) year following a single amendment. While soil salinity significantly decreased, there were large increases in leaf area index, plant performance, and maize grain yield, with a considerable decrease in leaf electrolyte leakage when grown in amendments. Maize leaf sap nitrogen, phosphorus and potassium increased while sodium and chloride decreased, leaf bioactivity related to osmotic stress was significantly improved following the treatments. These effects were generally greater in the second than in the first year. A combined amendment of crop straw biochar with manure compost plus pyroligneous solution could help combat salinity stress to maize and improve productivity in saline croplands in arid/semi-arid regions threatened increasingly by global climate change. © 2014 Society of Chemical Industry.

  2. Algal derivatives may protect crops from residual soil salinity: a case study on a tomato-wheat rotation

    Science.gov (United States)

    Di Stasio, Emilio; Raimondi, Giampaolo; Van Oosten, Michael; Maggio, Albino

    2017-04-01

    In coastal areas, summer crops are frequently irrigated with saline water. As a consequence, salts may accumulate in the root zone with detrimental effects on the following winter crops if the rainfall is insufficient to leach them. Two field experiments were performed in 2015-2016 on a field used for tomato (summer) wheat (winter) rotation cropping. The spring-summer experiment was carried in order to evaluate the effect of two algal derivatives (Ascophyllum nodosum), Rygex and Super Fifty, on a tomato crop exposed to increasing salinity and reduced nutrient availability. In the autumn-winter experiment we investigated the effect of residual salts from the previous summer irrigations on plant growth and yield of wheat treated with the same two algal extracts. The salt treatment for the irrigated summer crop was 80 mM NaCl plus a non-salinized control. The nutrient regimes were 100% and 50% of the tomato nutritional requirements. With both the seaweeds applications the salt stressed plants were demonstrated improved Relative Water Content and water potential. Nevertheless the total fresh biomass and the fruit fresh weight were enhanced only in the non salinized controls. Application of algal derivatives increased the total fresh weight over controls in the non salinized plants. The seaweed treatments enhanced the fruit fresh weight with an increase of 30% and 46% for Rygex and Super Fifty, respectively. Preliminary analysis of the ion profile in roots, shoots and leaves, indicates that the seaweed extracts may enhance the assimilation of ions in fruits affecting their nutritional value. The residual salinity of the summer experiment reduced the wheat biomass production. However, the seaweed extracts treatments improved growth under salinity. In the salt stressed plants the Super Fifty application increased shoots and ears by 34% and 23% respectively, compared to the non treated plants. Plant height was increased by application of seaweeds extracts for both the

  3. Comportamento hídrico e crescimento do feijão vigna cultivado em solos salinizados Hydric behaviour and growth of cowpea cultivated in salinized soils

    Directory of Open Access Journals (Sweden)

    José B. M. Coelho

    2013-04-01

    Full Text Available A salinização dos solos reduz a capacidade das plantas de absorver água o que, em geral, provoca diminuição na sua taxa de crescimento. As respostas das plantas ao estresse salino são melhor correlacionadas com o potencial osmótico do que com a condutividade elétrica do extrato de saturação do solo. Com o objetivo de avaliar os efeitos do estresse salino no crescimento, evapotranspiração e potencial osmótico foliar do feijoeiro vigna [Vigna unguiculata L. (Walp.] conduziu-se um experimento em casa de vegetação da Universidade Federal Rural de Pernambuco (Recife, PE, Brasil. Os tratamentos constaram de um arranjo fatorial 2 x 4 composto de duas texturas de solo e quatro níveis de salinidade do solo (4, 8 e 12 dS m-1 a 25 ºC além da testemunha sem a adição de sais com cinco repetições. Concluiu-se que a salinidade do solo causa redução no consumo de água, no potencial osmótico foliar, na altura das plantas, no número de folhas e na biomassa seca da parte aérea do feijoeiro vigna.Soil salinization reduces the capacity of plants to absorb water, and in general causes decrease in plant growth. Plant responses to salt stress are better correlated with osmotic potential compared to electrical conductivity of soil saturation extract. In order to evaluate the effect of salt stress on growth, water use and leaf osmotic potential of cowpea [Vigna unguiculata L. (Walp.], an experiment was carried out in a greenhouse of the Federal Rural University of Pernambuco (Recife-PE, Brazil. The Treatments were in a factorial arrangement of 2 x 4, comprising of two soil textures and four levels of soil salinity (4, 8 and 12 dS m-1 at 25 °C, and the control without salt addition with five replications. It was concluded that soil salinity causes reduction in water consumption, leaf osmotic potential, plant height, number of leaves and dry biomass of shoot of cowpea.

  4. Influence of Irrigation Water Discharge Frequency on Soil Salt Removal and Rice Yield in a Semi-Arid and Saline-Sodic Area

    Directory of Open Access Journals (Sweden)

    Zhigang Huang

    2013-05-01

    Full Text Available Irrigation practice for rice culture can be especially challenging in areas with limited water supply and soil salinization. In this study, we carried out a field experiment to assess the effects of different water discharge frequencies on soil salt content, rice yield and water use efficiency on a saline-sodic soil in a semi-arid region of Northeast China. The experiment comprised of three frequency levels of discharge [9-time (I-9-30, 6-time (I-6-30 and 3-time (I-3-30 discharge, all followed with a 30-mm irrigation] in comparison with the traditional irrigation practice of 2-time discharge followed with an 80-mm irrigation (I-2-80. Our initial hypothesis was that increasing discharge frequency would increase both salt reduction and rice yield. Daily precipitation was recorded by a nearby weather station, and evapotranspiration and soil water percolation rates were measured at experimental sites using soil pits. The measurements were used to establish a water balance for each treatment. Our results showed that soil salt reduction increased with the increasing discharge frequency at a 30-mm irrigation water depth. The 9-time discharge reduced a large amount of soil salt (995.0 kg ha−1 after five months of the study. Rice yield also increased with the increasing discharge frequency with a 30-mm irrigation water depth; however, when compared to the traditional 2-time discharge followed with an 80-mm irrigation, rice yield at the sites with more frequent discharge (i.e., I-9-30, I-6-30 and I-3-30 was 11%–18% lower. Because of this, rice yield and irrigation water use efficiency were significantly higher under the traditional practice of high-irrigation with low-frequency discharge (I-2-80 than under I-9-30, I-6-30 and I-3-30. These results indicate a need for a trade-off amongst salt reduction, rice yield and water use when considering selection of irrigation and discharge schedules.

  5. Impact of Soil Salinity on the Structure of the Bacterial Endophytic Community Identified from the Roots of Caliph Medic (Medicago truncatula.

    Directory of Open Access Journals (Sweden)

    Mahmoud W Yaish

    Full Text Available In addition to being a forage crop, Caliph medic (Medicago truncatula is also a model legume plant and is used for research focusing on the molecular characterization of the interaction between rhizobia and plants. However, the endophytic microbiome in this plant is poorly defined. Endophytic bacteria play a role in supplying plants with the basic requirements necessary for growth and development. Moreover, these bacteria also play a role in the mechanism of salinity stress adaptation in plants. As a prelude to the isolation and utilization of these bacteria in Caliph medic farming, 41 bacterial OTUs were identified in this project from within the interior of the roots of this plant by pyrosequencing of the small ribosomal subunit gene (16S rDNA using a cultivation-independent approach. In addition, the differential abundance of these bacteria was studied following exposure of the plants to salinity stress. About 29,064 high-quality reads were obtained from the sequencing of six libraries prepared from control and salinity-treated tissues. Statistical analysis revealed that the abundance of ~70% of the OTUs was significantly (p ≤ 0.05 altered in roots that were exposed to salinity stress. Sequence analysis showed a similarity between some of the identified species and other, known, growth-promoting bacteria, marine and salt-stressed soil-borne bacteria, and nitrogen-fixing bacterial isolates. Determination of the amendments to the bacterial community due to salinity stress in Caliph medic provides a crucial step toward developing an understanding of the association of these endophytes, under salt stress conditions, in this model plant. To provide direct evidence regarding their growth promoting activity, a group of endophytic bacteria were isolated from inside of plant roots using a cultivation-dependent approach. Several of these isolates were able to produce ACC-deaminase, ammonia and IAA; and to solubilize Zn+2 and PO4-3. This data is

  6. Impact of Soil Salinity on the Structure of the Bacterial Endophytic Community Identified from the Roots of Caliph Medic (Medicago truncatula).

    Science.gov (United States)

    Yaish, Mahmoud W; Al-Lawati, Abbas; Jana, Gerry Aplang; Vishwas Patankar, Himanshu; Glick, Bernard R

    2016-01-01

    In addition to being a forage crop, Caliph medic (Medicago truncatula) is also a model legume plant and is used for research focusing on the molecular characterization of the interaction between rhizobia and plants. However, the endophytic microbiome in this plant is poorly defined. Endophytic bacteria play a role in supplying plants with the basic requirements necessary for growth and development. Moreover, these bacteria also play a role in the mechanism of salinity stress adaptation in plants. As a prelude to the isolation and utilization of these bacteria in Caliph medic farming, 41 bacterial OTUs were identified in this project from within the interior of the roots of this plant by pyrosequencing of the small ribosomal subunit gene (16S rDNA) using a cultivation-independent approach. In addition, the differential abundance of these bacteria was studied following exposure of the plants to salinity stress. About 29,064 high-quality reads were obtained from the sequencing of six libraries prepared from control and salinity-treated tissues. Statistical analysis revealed that the abundance of ~70% of the OTUs was significantly (p ≤ 0.05) altered in roots that were exposed to salinity stress. Sequence analysis showed a similarity between some of the identified species and other, known, growth-promoting bacteria, marine and salt-stressed soil-borne bacteria, and nitrogen-fixing bacterial isolates. Determination of the amendments to the bacterial community due to salinity stress in Caliph medic provides a crucial step toward developing an understanding of the association of these endophytes, under salt stress conditions, in this model plant. To provide direct evidence regarding their growth promoting activity, a group of endophytic bacteria were isolated from inside of plant roots using a cultivation-dependent approach. Several of these isolates were able to produce ACC-deaminase, ammonia and IAA; and to solubilize Zn+2 and PO4-3. This data is consistent with the

  7. Heavy metal water pollution associated with the use of sewage sludge compost and limestone outcrop residue for soil restoration: effect of saline irrigation.

    Science.gov (United States)

    Pérez-Gimeno, Ana; Navarro-Pedreño, Jose; Gómez, Ignacio; Belén Almedro-Candel, María; Jordán, Manuel M.; Bech, Jaume

    2015-04-01

    The use of composted sewage sludge and limestone outcrop residue in soil restoration and technosol making can influence the mobility of heavy metals into groundwater. The use of compost from organic residues is a common practice in soil and land rehabilitation, technosol making, and quarry restoration (Jordán et al. 2008). Compost amendments may improve the physical, chemical, and biological properties of soils (Jordão et al. 2006; Iovieno et al. 2009). However, the use of compost and biosolids may have some negative effects on the environment (Karaca 2004; Navarro-Pedreño et al. 2004). This experiment analyzed the water pollution under an experimental design based on the use of columns (0-30 cm) formed by both wastes. Two waters of different quality (saline and non-saline) were used for irrigation. The presence of heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in the leachates was checked under controlled conditions inside a greenhouse (mean values: 20°±5°C and around 60% relative humidity). Sixteen 30-cm tall columns made of PVC pipe with internal diameters of 10.5 cm were prepared. The columns were filled with one of these materials: either sewage sludge compost (SW) or limestone outcrop residue (LR), fraction (water (NS) and the others were so with saline water (S) from the beginning of the experiment. Four treatments combining the quality of the irrigation water (saline and non-saline) and wastes were studied: SW-NS, SW-S, LR-NS, and LR-S. After 24 hours of irrigation on the first day of each week, the leachates were taken and analyzed the heavy metal content (AAS-ES espectometer). The environmental risk due to the presence of heavy metals associated with the use of these materials was very low in general (under 0.1 mg/L). The use of sewage sludge favoured the presence of these metals in the lecheates and no effect was observed in the case of limestone residue. The presence of metals in SW was the main source (although the composition was under the UE

  8. The impacts of irrigation with transferred and saline reclaimed water in the soil biological quality of two citrus species: Adaptations to low water availability

    Science.gov (United States)

    Bastida, Felipe; Abadía, Joaquín; García, Carlos; Torres, Irene; Ruiz Navarro, Antonio; José Alarcón, Juan; Nicolás, Emilio

    2017-04-01

    Mediterranean agroecosystems are limited by the availability of water and hence it is fundamental to find new water sources for sustainable agriculture in the face of climate change. Here, the effects of irrigation with water from different sources were analyzed in the soil microbial community and plant status of grapefruit and mandarin trees in a Mediterranean agro-ecosystem located in south-east of Spain. Four irrigation treatments were evaluated: i) water with an average electrical conductivity (EC) of 1.1 dS m-1 from the "Tagus-Segura" water-transfer canal (TW); ii) reclaimed water (EC = 3.21 dS m-1) from a wastewater-treatment-plant (RW); iii) irrigation with TW, except in the second stage of fruit development, when RW was applied (TWc); and iv) irrigation with RW except in the second stage, when TW was used (RWc). Phospholipid fatty acids indicated that microbial biomass was greater under grapefruit than under mandarin. In the case of grapefruit, TW showed a lower bacterial biomass than RW, RWc, and TWc, while RW showed the lowest values in the mandarin soil. In grapefruit soil, β-glucosidase and cellobiohydrolase activities, related to C cycling, were greater in RW and TWc than in TW and RWc. In mandarin soil, the greatest activity of these enzymes was found in TWc. The saline stress induced lower net photosynthesis (A) and stomatal conductance (gs) in plants of RW, RWc and TWc in comparison with TW. The annual use of reclaimed water or the combined irrigation with TWc positively influenced the soil biological quality of a grapefruit agro-ecosystem. Conversely, the mandarin soil community was more sensitive to the annual irrigation with RW.

  9. Exchangeable Sodium Percentage decrease in saline sodic soil after Basic Oxygen Furnace Slag application in a lysimeter trial.

    Science.gov (United States)

    Pistocchi, Chiara; Ragaglini, Giorgio; Colla, Valentina; Branca, Teresa Annunziata; Tozzini, Cristiano; Romaniello, Lea

    2017-12-01

    The Basic Oxygen Furnace Slag results from the conversion of hot metal into steel. Some properties of this slag, such as the high pH or calcium and magnesium content, makes it suitable for agricultural use as a soil amendment. Slag application to agricultural soils is allowed in some European countries, but to date there is no common regulation in the European Union. In Italy soils in coastal areas are often affected by excess sodium, which has several detrimental effects on the soil structure and crop production. In this study, carried out within an European project, the ability of the Basic Oxygen Furnace Slag to decrease the soil Exchangeable Sodium Percentage of a sodic soil was evaluated. A three-year lysimeter trial with wheat and tomato crops was carried out to assess the effects of two slag doses (D1, 3.5 g kg(-1)year(-1) and D, 2, 7 g kg(-1)year(-1)) on exchangeable cations in comparison with unamended soil. In addition, the accumulation in the topsoil of vanadium and chromium, the two main trace metals present in the Basic Oxygen Furnace Slag, was assessed. After two years, the soil Exchangeable Sodium Percentage was reduced by 40% in D1 and 45% in D2 compared to the control. A concomitant increase in exchangeable bivalent cations (Ca(++) and Mg(++)) was observed. We concluded that bivalent cations supplied with the slag competed with sodium for the sorption sites in the soil. The slag treatments also had a positive effect on tomato yields, which were higher than the control. Conversely the wheat yield was lower in the slag-amended soil, possibly because of the toxicity of vanadium added with the slag. This study showed that Basic Oxygen Furnace Slag decreased the Exchangeable Sodium Percentage, but precautions are needed to avoid the build up of toxic concentrations of trace metals in the soil, especially vanadium. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Effects of Betaine Aldehyde Dehydrogenase-Transgenic Soybean on Phosphatase Activities and Rhizospheric Bacterial Community of the Saline-Alkali Soil

    Directory of Open Access Journals (Sweden)

    Ying Nie

    2016-01-01

    Full Text Available The development of transgenic soybean has produced numerous economic benefits; however the potential impact of root exudates upon soil ecological systems and rhizospheric soil microbial diversity has also received intensive attention. In the present study, the influence of saline-alkali tolerant transgenic soybean of betaine aldehyde dehydrogenase on bacterial community structure and soil phosphatase during growth stages was investigated. The results showed that, compared with nontransgenic soybean as a control, the rhizospheric soil pH of transgenic soybean significantly decreased at the seedling stage. Compared to HN35, organic P content was 13.5% and 25.4% greater at the pod-filling stage and maturity, respectively. The acid phosphatase activity of SRTS was significantly better than HN35 by 12.74% at seedling, 14.03% at flowering, and 59.29% at podding, while alkaline phosphatase achieved maximum activity in the flowering stage and was markedly lower than HN35 by 13.25% at pod-filling. The 454 pyrosequencing technique was employed to investigate bacterial diversity, with a total of 25,499 operational taxonomic units (OTUs obtained from the 10 samples. Notably, the effect of SRTS on microbial richness and diversity of rhizospheric soil was marked at the stage of podding and pod-filling. Proteobacteria, Acidobacteria, and Actinobacteria were the dominant phyla among all samples. Compared with HN35, the relative abundance of Proteobacteria was lower by 2.01%, 2.06%, and 5.28% at the stage of seedling, at pod-bearing, and at maturity. In genus level, the relative abundance of Gp6, Sphingomonas sp., and GP4 was significantly inhibited by SRTS at the stage of pod-bearing and pod-filling.

  11. Grazing as an alternative for utilization of saline-sodic soils in the San Joaquin Valley: Selenium accretion and performance of beef heifers

    Energy Technology Data Exchange (ETDEWEB)

    Juchem, Sergio O., E-mail: sdjuchem@gmail.com [Department of Animal Science, University of California, Davis, CA 95616 (United States); Department of Plant Science, California State University, Fresno, CA 93740-8033 (United States); Benes, Sharon E. [Department of Plant Science, California State University, Fresno, CA 93740-8033 (United States); Robinson, P.H. [Department of Animal Science, University of California, Davis, CA 95616 (United States); Grattan, Stephen R. [Department of Land and Water Resources, University of California, Davis, CA 95616 (United States); Vasquez, Pablo [Department of Plant Science, California State University, Fresno, CA 93740-8033 (United States); Chilibroste, Pablo [Instituto Nacional de Investigacion Agropecuaria, Paysandu (Uruguay); Brito, Martin [Department of Plant Science, California State University, Fresno, CA 93740-8033 (United States)

    2012-03-01

    Two experiments were conducted to evaluate Se accumulation and health of non-pregnant, non-breeding beef cattle grazing on forages with a high Se content due to irrigation with saline drainage water. Heifers grazed experimental pastures of 'Jose' tall wheatgrass (TWG; Thinopyrum ponticum var. 'Jose') and creeping wildrye (CWR; Leymus triticoides var. 'Rio') for190 days in Experiment 1 (2007) and for 165 days in Experiment 2 (2008). In experiment 1, mean Se concentrations were similar in TWG and CWR herbage (4.0 versus 3.7 {+-} 0.26 mg/kg dry weight; p = 0.34) as was crude protein (113 versus 114 {+-} 7.9 g/kg dry weight; p = 0.94). Concentrations of Se in blood increased by 300% during the grazing period, and were similar for heifers grazing the TWG or CWR pastures (0.94 versus 0.87 {+-} 0.03 mg/kg; p = 0.89). Heifers grazing on TWG gained more body weight than did heifers grazing on CWR (0.59 versus 0.27 {+-} 0.07 kg/days; p < 0.01). In experiment 2, concentration of Se (4.0 versus 2.8 mg/kg {+-} 0.19 mg/kg dry weight; p < 0.01) and crude protein (79 versus 90 {+-} 5.6 g/kg dry weight; p < 0.01) differed, for TWG and CWR, respectively. Within 20 days, Se concentrations in blood had increased by 300% and by nearly 200% in heifers grazing on TWG or CWR. All data cited are least square means {+-} standard error of the mean. Data from our two grazing seasons are consistent in demonstrating the safety of grazing beef cattle for a period of up to 6 months on TWG and CWR forages having high levels of Se due to irrigation with saline drainage water. This suggests that forage production using saline drainage water is a viable alternative for saline soils with limited potential for producing high value, salt-sensitive, crops. - Highlights: Black-Right-Pointing-Pointer Forages irrigated with saline drainage water may contain high levels of selenium. Black-Right-Pointing-Pointer High concentration of selenium in forages can be toxic to grazing

  12. Effects of biosolids application on nitrogen dynamics and microbial structure in a saline-sodic soil of the former Lake Texcoco (Mexico).

    Science.gov (United States)

    Rojas-Oropeza, M; Dendooven, L; Garza-Avendaño, L; Souza, V; Philippot, L; Cabirol, N

    2010-04-01

    The saline-sodic soil of the former Lake Texcoco, a large area exposed to desertification, is a unique environment, but little is known about its microbial ecology. The objective of this study was to examine bacterial community structure, activity, and function when biosolids were added to microcosms. The application rates were such that 0, 66, 132, or 265 mg total Nk g(-1) were added with the biosolids (total C and N content 158 and 11.5 g kg(-1) dry biosolids, respectively). Approximately 60% of the biosolids were mineralized within 90 days. Microbial respiration and to a lesser extent ammonification and nitrification, increased after biosolids application. The rRNA intergenic spacer analysis (RISA) patterns for the biosolids and unamended soil bacterial communities were different, indicating that the microorganisms in the biosolids were distinct from the native population. It appears that the survival of the allochthonous microorganisms was short, presumably due to the adverse soil conditions. Copyright 2009 Elsevier Ltd. All rights reserved.

  13. Study of the influence of the saline solution NaCl on the potential collapse of soil

    Directory of Open Access Journals (Sweden)

    Abbeche Khelifa

    2016-01-01

    Full Text Available Collapsible soils are unsaturated soils which present a potential for large strains and a complete change to the whole particle structure after wetting with or without loading. These soils are characterized with loose structures composed of silt to fine-sand-size particles.The objective of this experimental study is to illustrate that the resistance of collapsible soil can be improved. This study demonstrates that it is possible to minimize the collapsible potential Cp to an acceptable level after chemical treatment with salt (sodium chloride NaCl at different concentrations (0.5, 1.0, 1.5 and 2.0 mole/liter and at different compaction energies. The method used in this study is based on oedometric tests with variable normal stresses.

  14. SMEX03 Little Washita Micronet Soil Moisture Data: Oklahoma

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains volumetric soil moisture, soil temperature, soil conductivity, soil salinity, and surface temperature data collected during the Soil Moisture...

  15. Indicators: Salinity

    Science.gov (United States)

    Salinity is the dissolved salt content of a body of water. Excess salinity, due to evaporation, water withdrawal, wastewater discharge, and other sources, is a chemical sterssor that can be toxic for aquatic environments.

  16. Conspecific plasticity and invasion: invasive populations of Chinese tallow (Triadica sebifera have performance advantage over native populations only in low soil salinity.

    Directory of Open Access Journals (Sweden)

    Leiyi Chen

    Full Text Available Global climate change may increase biological invasions in part because invasive species may have greater phenotypic plasticity than native species. This may be especially important for abiotic stresses such as salt inundation related to increased hurricane activity or sea level rise. If invasive species indeed have greater plasticity, this may reflect genetic differences between populations in the native and introduced ranges. Here, we examined plasticity of functional and fitness-related traits of Chinese tallow (Triadica sebifera populations from the introduced and native ranges that were grown along a gradient of soil salinity (control: 0 ppt; Low: 5 ppt; Medium: 10 ppt; High: 15 ppt in a greenhouse. We used both norm reaction and plasticity index (PIv to estimate the conspecific phenotypic plasticity variation between invasive and native populations. Overall, invasive populations had higher phenotypic plasticity of height growth rate (HGR, aboveground biomass, stem biomass and specific leaf area (SLA. The plasticity Index (PIv of height growth rate (HGR and SLA each were higher for plants from invasive populations. Absolute performance was always comparable or greater for plants from invasive populations versus native populations with the greatest differences at low stress levels. Our results were consistent with the "Master-of-some" pattern for invasive plants in which the fitness of introduced populations was greater in more benign conditions. This suggests that the greater conspecific phenotypic plasticity of invasive populations compared to native populations may increase invasion success in benign conditions but would not provide a potential interspecific competitive advantage in higher salinity soils that may occur with global climate change in coastal areas.

  17. Impact of defoliation intensities on plant biomass, nutrient uptake and arbuscular mycorrhizal symbiosis in Lotus tenuis growing in a saline-sodic soil.

    Science.gov (United States)

    García, I; Mendoza, R

    2012-11-01

    The impact of different defoliation intensities on the ability of Lotus tenuis plants to regrowth, mobilise nutrients and to associate with native AM fungi and Rhizobium in a saline-sodic soil was investigated. After 70 days, plants were subjected to 0, 25, 50, 75 and 100% defoliation and shoot regrowth was assessed at the end of subsequent 35 days. Compared to non-defoliated plants, low or moderate defoliation up to 75% did not affect shoot regrowth. However, 100% treatment affected shoot regrowth and the clipped plants were not able to compensate the growth attained by non-defoliated plants. Root growth was more affected by defoliation than shoot growth. P and N concentrations in shoots and roots increased with increasing defoliation while Na(+) concentration in shoots of non-defoliated and moderately defoliated plants was similar. Non-defoliated and moderately defoliated plants prevented increases of Na(+) concentration in shoots through both reducing Na(+) uptake and Na(+) transport to shoots by accumulating Na(+) in roots. At high defoliation, the salinity tolerance mechanism is altered and Na(+) concentration in shoots was higher than in roots. Reduction in the photosynthetic capacity induced by defoliation neither changed the root length colonised by AM fungi nor arbuscular colonisation but decreased the vesicular colonisation. Spore density did not change, but hyphal density and Rhizobium nodules increased with defoliation. The strategy of the AM symbiont consists in investing most of the C resources to preferentially retain arbuscular colonisation as well as inoculum density in the soil. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  18. under salinity stress

    African Journals Online (AJOL)

    ajl yemi

    2011-11-14

    Nov 14, 2011 ... (2002) reported that K and Zn deficiencies in the plant were mainly induced by soil salinity. Zhang et al. (2011) investigated the effects of applying different concentra- tions of the macronutrients K+, Ca2+ and Mg2+ on the responses of contrasting rice (O. sativa L.) genotypes under salt stress. A solution ...

  19. [Adaptability of Helianthus annuus seedlings to crude oil pollution in soil and its improvement measures under salinization stress].

    Science.gov (United States)

    Zhang, Jing-lei; Ci, Hua-cong; He, Xing-dong; Liang, Yu-ting; Zhao, Xuan; Sun, Hui-ting; Xie, Hong-tao

    2015-11-01

    To explore the adaptability of plant under salt stress to crude oil pollution of soil and improvement measures, a pot experiment of Helianthus annuus seedlings was conducted using orthogonal experiment method with crude oil-sodium chloride-desulfurization gypsum and cinder-zeolite-desulfurization gypsum-sawdust. The results showed that, with the increase of soil crude oil concentration, the relative growth rate (RGR) of plant height, RGR of aboveground biomass and root N: P ratios of H. annuus seedlings decreased significantly, while the activity of SOD and CAT increased at first and then decreased significantly. The RGR of plant height and aboveground biomass significantly increased (P pollution of soil could decrease the relative growth rate of H. annuus seedling, and sawdust could reduce the influence of crude oil pollution on plant growth under salt stress.

  20. Rhizophoraceae Mangrove Saplings Use Hypocotyl and Leaf Water Storage Capacity to Cope with Soil Water Salinity Changes

    Science.gov (United States)

    Lechthaler, Silvia; Robert, Elisabeth M. R.; Tonné, Nathalie; Prusova, Alena; Gerkema, Edo; Van As, Henk; Koedam, Nico; Windt, Carel W.

    2016-01-01

    Some of the most striking features of Rhizophoraceae mangrove saplings are their voluminous cylinder-shaped hypocotyls and thickened leaves. The hypocotyls are known to serve as floats during seed dispersal (hydrochory) and store nutrients that allow the seedling to root and settle. In this study we investigate to what degree the hypocotyls and leaves can serve as water reservoirs once seedlings have settled, helping the plant to buffer the rapid water potential changes that are typical for the mangrove environment. We exposed saplings of two Rhizophoraceae species to three levels of salinity (15, 30, and 0–5‰, in that sequence) while non-invasively monitoring changes in hypocotyl and leaf water content by means of mobile NMR sensors. As a proxy for water content, changes in hypocotyl diameter and leaf thickness were monitored by means of dendrometers. Hypocotyl diameter variations were also monitored in the field on a Rhizophora species. The saplings were able to buffer rapid rhizosphere salinity changes using water stored in hypocotyls and leaves, but the largest water storage capacity was found in the leaves. We conclude that in Rhizophora and Bruguiera the hypocotyl offers the bulk of water buffering capacity during the dispersal phase and directly after settlement when only few leaves are present. As saplings develop more leaves, the significance of the leaves as a water storage organ becomes larger than that of the hypocotyl. PMID:27446125

  1. Rhizophoraceae Mangrove Saplings Use Hypocotyl and Leaf Water Storage Capacity to Cope with Soil Water Salinity Changes.

    Science.gov (United States)

    Lechthaler, Silvia; Robert, Elisabeth M R; Tonné, Nathalie; Prusova, Alena; Gerkema, Edo; Van As, Henk; Koedam, Nico; Windt, Carel W

    2016-01-01

    Some of the most striking features of Rhizophoraceae mangrove saplings are their voluminous cylinder-shaped hypocotyls and thickened leaves. The hypocotyls are known to serve as floats during seed dispersal (hydrochory) and store nutrients that allow the seedling to root and settle. In this study we investigate to what degree the hypocotyls and leaves can serve as water reservoirs once seedlings have settled, helping the plant to buffer the rapid water potential changes that are typical for the mangrove environment. We exposed saplings of two Rhizophoraceae species to three levels of salinity (15, 30, and 0-5‰, in that sequence) while non-invasively monitoring changes in hypocotyl and leaf water content by means of mobile NMR sensors. As a proxy for water content, changes in hypocotyl diameter and leaf thickness were monitored by means of dendrometers. Hypocotyl diameter variations were also monitored in the field on a Rhizophora species. The saplings were able to buffer rapid rhizosphere salinity changes using water stored in hypocotyls and leaves, but the largest water storage capacity was found in the leaves. We conclude that in Rhizophora and Bruguiera the hypocotyl offers the bulk of water buffering capacity during the dispersal phase and directly after settlement when only few leaves are present. As saplings develop more leaves, the significance of the leaves as a water storage organ becomes larger than that of the hypocotyl.

  2. Grazing as an alternative for utilization of saline-sodic soils in the San Joaquin Valley: selenium accretion and performance of beef heifers.

    Science.gov (United States)

    Juchem, Sérgio O; Benes, Sharon E; Robinson, P H; Grattan, Stephen R; Vasquez, Pablo; Chilibroste, Pablo; Brito, Martin

    2012-03-01

    Two experiments were conducted to evaluate Se accumulation and health of non-pregnant, non-breeding beef cattle grazing on forages with a high Se content due to irrigation with saline drainage water. Heifers grazed experimental pastures of "Jose" tall wheatgrass (TWG; Thinopyrum ponticum var. "Jose") and creeping wildrye (CWR; Leymus triticoides var. "Rio") for 190 days in Experiment 1 (2007) and for 165 days in Experiment 2 (2008). In experiment 1, mean Se concentrations were similar in TWG and CWR herbage (4.0 versus 3.7 ± 0.26 mg/kg dry weight; p=0.34) as was crude protein (113 versus 114 ± 7.9 g/kg dry weight; p=0.94). Concentrations of Se in blood increased by 300% during the grazing period, and were similar for heifers grazing the TWG or CWR pastures (0.94 versus 0.87 ± 0.03 mg/kg; p=0.89). Heifers grazing on TWG gained more body weight than did heifers grazing on CWR (0.59 versus 0.27 ± 0.07 kg/days; p<0.01). In experiment 2, concentration of Se (4.0 versus 2.8 mg/kg ± 0.19 mg/kg dry weight; p<0.01) and crude protein (79 versus 90 ± 5.6 g/kg dry weight; p<0.01) differed, for TWG and CWR, respectively. Within 20 days, Se concentrations in blood had increased by 300% and by nearly 200% in heifers grazing on TWG or CWR. All data cited are least square means ± standard error of the mean. Data from our two grazing seasons are consistent in demonstrating the safety of grazing beef cattle for a period of up to 6 months on TWG and CWR forages having high levels of Se due to irrigation with saline drainage water. This suggests that forage production using saline drainage water is a viable alternative for saline soils with limited potential for producing high value, salt-sensitive, crops. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Response of nitrogen dynamics in semi-natural and agricultural grassland soils to experimental variation in tide and salinity

    NARCIS (Netherlands)

    Antheunisse, A.M.; Loeb, R.; Miletto, M.; Lamers, L.P.M.; Laanbroek, H.J.; Verhoeven, J.T.A.

    2007-01-01

    In the framework of rehabilitation efforts to enhance the ecological value of closed-off estuaries, we studied the effects of restoring a tidal movement and seawater incursion on soil nitrogen conversion rates and vegetation response of semi-natural and agricultural grasslands in an outdoor mesocosm

  4. Plant growth promoting effect of Bacillus amyloliquefaciens H-2-5 on crop plants and influence on physiological changes in soybean under soil salinity.

    Science.gov (United States)

    Kim, Min-Ji; Radhakrishnan, Ramalingam; Kang, Sang-Mo; You, Young-Hyun; Jeong, Eun-Ju; Kim, Jong-Guk; Lee, In-Jung

    2017-07-01

    This study was aimed to identify plant growth-promoting bacterial isolates from soil samples and to investigate their ability to improve plant growth and salt tolerance by analysing phytohormones production and phosphate solubilisation. Among the four tested bacterial isolates (I-2-1, H-1-4, H-2-3, and H-2-5), H-2-5 was able to enhance the growth of Chinese cabbage, radish, tomato, and mustard plants. The isolated bacterium H-2-5 was identified as Bacillus amyloliquefaciens H-2-5 based on 16S rDNA sequence and phylogenetic analysis. The secretion of gibberellins (GA4, GA8, GA9, GA19, and GA20) from B. amyloliquefaciens H-2-5 and their phosphate solubilisation ability may contribute to enhance plant growth. In addition, the H-2-5-mediated mitigation of short term salt stress was tested on soybean plants that were affected by sodium chloride. Abscisic acid (ABA) produced by the H-2-5 bacterium suppressed the NaCl-induced stress effects in soybean by enhancing plant growth and GA4 content, and by lowering the concentration of ABA, salicylic acid, jasmonic acid, and proline. These results suggest that GAs, ABA production, and the phosphate solubilisation capacity of B. amyloliquefaciens H-2-5 are important stimulators that promote plant growth through their interaction and also to improve plant growth by physiological changes in soybean at saline soil.

  5. Saline agriculture in Mediterranean environments

    Directory of Open Access Journals (Sweden)

    Albino Maggio

    2011-03-01

    Full Text Available Salinization is increasingly affecting world's agricultural land causing serious yield loss and soil degradation. Understanding how we could improve crop productivity in salinized environments is therefore critical to meet the challenging goal of feeding 9.3 billion people by 2050. Our comprehension of fundamental physiological mechanisms in plant salt stress adaptation has greatly advanced over the last decades. However, many of these mechanisms have been linked to salt tolerance in simplified experimental systems whereas they have been rarely functionally proven in real agricultural contexts. In-depth analyses of specific crop-salinity interactions could reveal important aspects of plant salt stress adaptation as well as novel physiological/agronomic targets to improve salinity tolerance. These include the developmental role of root vs. shoot systems respect to water-ion homeostasis, morphological vs. metabolic contributions to stress adaptation, developmental processes vs. seasonal soil salinity evolution, residual effects of saline irrigation in non-irrigated crops, critical parameters of salt tolerance in soil-less systems and controlled environments, response to multiple stresses. Finally, beneficial effects of salinization on qualitative parameters such as stress-induced accumulation of high nutritional value secondary metabolites should be considered, also. In this short review we attempted to highlight the multifaceted nature of salinity in Mediterranean agricultural systems by summarizing most experimental activity carried out at the Department of Agricultural Engineering and Agronomy of University of Naples Federico II in the last few years.

  6. EVALUACIÓN DE TECNOLOGÍAS PARA LA RECUPERACIÓN DE SUELOS DEGRADADOS POR SALINIDAD EVALUATION OF TECHNOLOGIES FOR THE RECOVERY OF SOILS DEGRADED BY SALINITY

    Directory of Open Access Journals (Sweden)

    Orlando Zúñiga Escobar

    2011-06-01

    Full Text Available La presencia de salinidad y sodio en los suelos interfiere en el crecimiento adecuado de la mayoría de los cultivos y por lo tanto constituye uno de los problemas más serios que enfrenta la agricultura sostenible. Se evaluaron una serie de tecnologías no convencionales utilizadas en recuperación de suelos afectados por salinidad según la respuesta agronómica de un cultivo de maíz. Se planteó la aplicación de 3 tratamientos alternativos: 1 Biofertilizantes, 2 Biopolimeros y 3 Electromagnetismo comparados frente a la propuesta: 4 Convencional con base en la teoría del USDA (United States Departament of Agriculture de enmiendas químicas (yeso - azufre. Además de un testigo absoluto (Sólo drenaje. Los tratamientos más efectivos en cuanto respuesta fisiológica y productividad fueron los biológicos con uso de microorganismos (biofertlizantes y electromagnetismo, se incluyó la estimulación electromagnética la cual acelera la actividad microbiana para disminuir el tiempo de recuperación de suelos afectados por salinidad del suelo.Salinity and sodium content in soils interferes with proper growth of most crops and therefore constitutes a serious problem facing sustainable agriculture. The objective of this research was to evaluate a series of unconventional technologies used in recovery of salt-affected soils according to the agronomic response of a maize crop. The application of three alternative treatments with Biofertilizers, Biopolymers and Electromagnetism were proposed to make a comparison with the USDA-based conventional theory approach (United States Department of Agriculture of chemical amendments (gypsum - sulfur. In addition to an absolute control (drainage only. The most effective treatments in terms of physiological response and productivity were the biological using microorganisms (biofertilizers and electromagnetism, clarifying that electromagnetic stimulation was included to accelerate microbial activity and lower soil

  7. Effects of phosphorus on the growth and chlorophyll fluorescence of a Dunaliella salina strain isolated from saline soil under nitrate limitation

    Directory of Open Access Journals (Sweden)

    Tassnapa Wongsnansilp

    2016-12-01

    Full Text Available An isolated Dunaliella salina (D. salina KU XI from saline soils in northeastern Thailand was cultured in f/2 medium in column photobioreactor. The variations of the growth, chlorophyll and beta-carotene content and the maximum quantum yield of PS II photochemistry (Fv/Fm under different NaH2PO4 concentrations were studied. Based on the results, the growth kinetics of D. salina KU XI was established, which could simulate the algae growth rate under different phosphate concentrations and temperatures. The phosphorus could significantly affect the growth and pigments accumulations of this isolated strain. Increasing NaH2PO4 concentration improved the biomass, the total chlorophyll and beta-carotene content, retarded the decrease of Fv/Fm value. The optimal phosphate concentration for the growth of D. salina KU XI was above 72.6 μM. The maximum biomass and beta-carotene were 0.24 g L-1 and 17.4 mg L-1 respectively when NaH2PO4 was 290.4 μM. The algae growth was restrained by phosphate or nitrate when NaH2PO4 below 12.1 μM or above 72.6 μM. It indicated that properly supplementing nitrate in the late growth stage with high phosphate concentration was favored for enhancing the growth and biomass production.

  8. An image analysis of TLC patterns for quality control of saffron based on soil salinity effect: A strategy for data (pre)-processing.

    Science.gov (United States)

    Sereshti, Hassan; Poursorkh, Zahra; Aliakbarzadeh, Ghazaleh; Zarre, Shahin; Ataolahi, Sahar

    2018-01-15

    Quality of saffron, a valuable food additive, could considerably affect the consumers' health. In this work, a novel preprocessing strategy for image analysis of saffron thin layer chromatographic (TLC) patterns was introduced. This includes performing a series of image pre-processing techniques on TLC images such as compression, inversion, elimination of general baseline (using asymmetric least squares (AsLS)), removing spots shift and concavity (by correlation optimization warping (COW)), and finally conversion to RGB chromatograms. Subsequently, an unsupervised multivariate data analysis including principal component analysis (PCA) and k-means clustering was utilized to investigate the soil salinity effect, as a cultivation parameter, on saffron TLC patterns. This method was used as a rapid and simple technique to obtain the chemical fingerprints of saffron TLC images. Finally, the separated TLC spots were chemically identified using high-performance liquid chromatography-diode array detection (HPLC-DAD). Accordingly, the saffron quality from different areas of Iran was evaluated and classified. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Characterization of Strains unlike Mesorhizobium loti That Nodulate Lotus spp. in Saline Soils of Granada, Spain ▿ †

    Science.gov (United States)

    Lorite, María J.; Muñoz, Socorro; Olivares, José; Soto, María J.; Sanjuán, Juan

    2010-01-01

    Lotus species are forage legumes with potential as pastures in low-fertility and environmentally constrained soils, owing to their high persistence and yield under those conditions. The aim of this work was the characterization of phenetic and genetic diversity of salt-tolerant bacteria able to establish efficient symbiosis with Lotus spp. A total of 180 isolates able to nodulate Lotus corniculatus and Lotus tenuis from two locations in Granada, Spain, were characterized. Molecular identification of the isolates was performed by repetitive extragenic palindromic PCR (REP-PCR) and 16S rRNA, atpD, and recA gene sequence analyses, showing the presence of bacteria related to different species of the genus Mesorhizobium: Mesorhizobium tarimense/Mesorhizobium tianshanense, Mesorhizobium chacoense/Mesorhizobium albiziae, and the recently described species, Mesorhizobium alhagi. No Mesorhizobium loti-like bacteria were found, although most isolates carried nodC and nifH symbiotic genes closely related to those of M. loti, considered the type species of bacteria nodulating Lotus, and other Lotus rhizobia. A significant portion of the isolates showed both high salt tolerance and good symbiotic performance with L. corniculatus, and many behaved like salt-dependent bacteria, showing faster growth and better symbiotic performance when media were supplemented with Na or Ca salts. PMID:20435777

  10. SMEX03 Little River Micronet Soil Moisture Data: Georgia

    Data.gov (United States)

    National Aeronautics and Space Administration — Parameters for this data set include precipitation, soil temperature, volumetric soil moisture, soil conductivity, and soil salinity measured in the Little River...

  11. Variabilidade espacial da salinidade de um solo aluvial no semi-árido Paraibano Spatial variability of soil salinity in an alluvial soil of the semi-arid region of Paraíba state

    Directory of Open Access Journals (Sweden)

    Lázaro Costa de Souza

    2000-04-01

    the salinity and sodicity variability, constituting a tool for the definition of soil management and reclamation of the affected area. Key words: salinization, exchangeable sodium percentage, geostatistics

  12. Evolución de la salinidad en un suelo irrigado del sudoeste bonaerense Soil salinity evolution under irrigation in southwestern Buenos Aires

    Directory of Open Access Journals (Sweden)

    María Elina Aguirre

    2011-12-01

    Full Text Available Este trabajo es un estudio de la influencia del riego por goteo sobre la salinidad y sodicidad del suelo en una plantación de olivo de 50 años de edad, cercana a la localidad de Faro, distrito de Coronel Dorrego, provincia de Buenos Aires. El agua utilizada tiene una conductividad eléctrica de 2,1 dSm-1 y una relación de adsorción de sodio (RAS 13,8. El sistema de irrigación está compuesto por dos líneas de goteros por fila de árboles. Los emisores presentan un caudal de 1 Lh-1 y están espaciados a 0,7 m. La toma de muestras se efectuó en una parcela de 50 por 1.000 m, cuatro muestras al inicio, dos en el medio y dos al final. En cada ubicación se tomaron muestras para cada uno de los cuatro horizontes del perfil, debajo del gotero y entre goteros. La salinidad y la sodicidad fueron analizadas en relación con los valores experimentales de la conductividad eléctrica (CEes y los de RAS calculados, ambos de los extractos de saturación de las muestras. Después de tres temporadas de irrigación se determinó que a la CEes se incrementa hasta valores cercanos a los del agua de irrigación, b el incremento de RAS es superior en diez veces los valores iniciales. De acuerdo con esto la aparición de problemas de sodicidad es altamente probable sin una enmienda del RAS del agua de irrigación. El comportamiento observado implica la siguiente cuestión: ¿el tipo y concentración de sales del agua de irrigación y las condiciones climáticas son compatibles para el cultivo sustentable del olivo en el sudoeste bonaerense? Para contestar esta pregunta se necesitan estudios posteriores en un período de tiempo más amplio, ya que la mayoría de los sitios muestreados no exhiben estabilidad temporal en relación con las condiciones promedio de salinidad y alcalinidad del suelo.The objective of this study was to elucidate the effect of drip irrigation on the salinity and sodicity of the soil under a 50-year old olive plantation, located near the

  13. Salinity Energy.

    Science.gov (United States)

    Schmitt, Walter R.

    1987-01-01

    Discussed are the costs of deriving energy from the earth's natural reserves of salt. Argues that, as fossil fuel supplies become more depleted in the future, the environmental advantages of salinity power may prove to warrant its exploitation. (TW)

  14. Using causal loop diagrams for the initialization of stakeholder engagement in soil salinity management in agricultural watersheds in developing countries: a case study in the Rechna Doab watershed, Pakistan.

    Science.gov (United States)

    Inam, Azhar; Adamowski, Jan; Halbe, Johannes; Prasher, Shiv

    2015-04-01

    Over the course of the last twenty years, participatory modeling has increasingly been advocated as an integral component of integrated, adaptive, and collaborative water resources management. However, issues of high cost, time, and expertise are significant hurdles to the widespread adoption of participatory modeling in many developing countries. In this study, a step-wise method to initialize the involvement of key stakeholders in the development of qualitative system dynamics models (i.e. causal loop diagrams) is presented. The proposed approach is designed to overcome the challenges of low expertise, time and financial resources that have hampered previous participatory modeling efforts in developing countries. The methodological framework was applied in a case study of soil salinity management in the Rechna Doab region of Pakistan, with a focus on the application of qualitative modeling through stakeholder-built causal loop diagrams to address soil salinity problems in the basin. Individual causal loop diagrams were developed by key stakeholder groups, following which an overall group causal loop diagram of the entire system was built based on the individual causal loop diagrams to form a holistic qualitative model of the whole system. The case study demonstrates the usefulness of the proposed approach, based on using causal loop diagrams in initiating stakeholder involvement in the participatory model building process. In addition, the results point to social-economic aspects of soil salinity that have not been considered by other modeling studies to date. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. The Effects of Light, Temperature, and Nutrition on Growth and Pigment Accumulation of Three Dunaliella salina Strains Isolated from Saline Soil.

    Science.gov (United States)

    Wu, Zhe; Duangmanee, Promchup; Zhao, Pu; Juntawong, Niran; Ma, Chunhong

    2016-01-01

    Developing algal industries in saline-alkali areas is necessary. However, suitable strains and optimal production conditions must be studied before widespread commercial use. The effects of light, temperature, KNO3, and CO(NH2)2 on beta-carotene and biomass accumulation were compared and evaluated in order to provide scientific guidance for commercial algal production in northeastern Thailand. An orthogonal design was used for evaluating optimal conditions for the algal production of three candidate Dunaliella salina strains (KU XI, KU 10 and KU 31) which were isolated from saline soils and cultured in the column photobioreactor. The optimal light and temperature for algae growth were 135.3 μmol m(-2) s(-1) and 22°C, while the conditions of 245.6 μmol m(-2) s(-1) and 22°C induced the highest level of beta-carotene production (117.99 mg L(-1)). The optimal concentrations of KNO3, CO(NH2)2, and NaHCO3 for algae growth were 0.5 g L(-1), 0.36 g L(-1), and 1.5 g L(-1), respectively, while 0, 0.12 g L(-1) and 1.5 g L(-1) were best suited for beta-carotene accumulation. The highest beta-carotene rate per cell appeared with the highest light intensity (12.21 pg) and lowest temperature (12.47 pg), and the lowest total beta-carotene content appeared at the lowest temperature (15°C). There was not a significant difference in biomass accumulation among the three Dunaliella strains; however, the beta-carotene accumulation of KU XI was higher than that of the other two strains. Light and temperature were both relevant factors that contributed to the growth and beta-carotene accumulation of the three D. salina strains, and NaHCO3 had significantly positive effects on growth. The degree of impact of the different factors on cell growth was temperature > NaHCO3 > light intensity > KNO3 > CO (NH2)2 > strains; the impact on beta-carotene accumulation was temperature > light intensity > KNO3 > CO (NH2)2 > strains > NaHCO3.

  16. Soils

    Science.gov (United States)

    Emily Moghaddas; Ken Hubbert

    2014-01-01

    When managing for resilient forests, each soil’s inherent capacity to resist and recover from changes in soil function should be evaluated relative to the anticipated extent and duration of soil disturbance. Application of several key principles will help ensure healthy, resilient soils: (1) minimize physical disturbance using guidelines tailored to specific soil types...

  17. Effluent salinity of pipe drains and tube-wells : a case study from the Indus plain

    NARCIS (Netherlands)

    Kelleners, T.J.

    2001-01-01

    Keywords: anisotropy, aquifer, desalinization, effluent salinity, groundwater, irrigation, salt-water upconing, soil salinity, stream-function, subsurface drainage

    Irrigated agriculture in arid and semi-arid zones often suffers from waterlogging and salinity problems.

  18. Effects of salinity and nitrogen on cotton growth in arid environment

    OpenAIRE

    Chen, Weiping; Hou, Zhenan; Wu, Laosheng; Liang, Yongchao; Wei, Changzhou

    2010-01-01

    The influences of different N fertilization rates and soil salinity levels on the growth and nitrogen uptake of cotton was evaluated with a pot experiment under greenhouse conditions. Results showed that cotton growth measured as plant height was significantly affected by the soil salinity and N-salinity interaction, but not by N alone. Cotton was more sensitive to salinity during the emergence and early growth stages than the later developmental stages. At low to moderate soil salinity, the ...

  19. Effects of Amendment of Biochar and Pyroligneous Solution from wheat straw pyrolysis on Yield and soil and crop