Thematische Bibliographien / Soils Agricultural chemical content

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  3. Bücher
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Auswahl der wissenschaftlichen Literatur zum Thema „Soils Agricultural chemical content“

Autor: Grafiati
Veröffentlicht am 4. Juni 2021
Zuletzt aktualisiert am 31. Januar 2023

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Zeitschriftenartikel zum Thema "Soils Agricultural chemical content"

1

Orlov, P. M., V. G. Sychov und N. I. Akanova. „RADIATSIONNYI REGIME OF SOILS OF AGRICULTURAL LANDS OF SIBERIA IN CONDITIONS OF VARIOUS INTENSITY OF CHEMICAL USE AND PROLONGED AFTEREFFECT CHEMICAL RECLAMATION“. Innovations and Food Safety, Nr. 2 (02.07.2020): 112–18. http://dx.doi.org/10.31677/2311-0651-2019-24-2-112-118.

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Presents the results of radiation monitoring local soils agricultural land in Siberia. At the level of the constituent entities of the Russian Federation appreciated the power of gamma radiation exposure dose (MJeDG), technotronic and content of natural radionuclides in different types of soils in Siberia. Set MJeDG change within 8.0–12.2 mcr/h, 137Cs content in the range of 4.3–9.9 Bq/kg, 90Sr-1.0–5.4 Bq/kg, 226Ra-15–37 Bq/kg, 232Th-16–40 Bq/kg. Comparison with similar parameters obtained, characterizing the radiation situation in soils of agricultural land in Russia. MJeDG, the content of 90Sr and content of natural radionuclides in soils of Siberia correspond to those for Russia. Content of 137Cs in soils in –2.6 1.7 times, in crop production in –2.3 1.6 times lower than in Russia. Content of natural radionuclides in soils of Siberia close to the contents in the soils in Russia on average and the planet. According to local monitoring radiation situation in agricultural fields.
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Ishak, Lily, und Philip Hugh Brown. „Soil Microbial Activity and Diversity in Response to Soil Chemical Factors in Agricultural Soils“. JOURNAL OF TROPICAL SOILS 24, Nr. 1 (02.01.2019): 43. http://dx.doi.org/10.5400/jts.2019.v24i1.43-51.

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The role of microbial communities in maintaining soil health is mostly influenced by chemical condition of soil. Microbial communities vary in response to soil chemical factors. The contradictive results from previous findings emphasise that it is difficult to define a pattern of the influence of soil chemical factors on soil microbial diversity and activity. The aim of the study was to assess soil microbial responses to soil chemical factors in agricultural soils. Composite soil (Dermosol order) samples taken from 16 commercial crop sites in Bundaberg, Queensland, Australia, were chemically and biologically analysed. It was found that bacterial and fungal activity and diversity were significantly affected by soil EC, SOM and NO3-N content, but were not influenced by soil pH, CEC, and Ca:Mg ratio. The diversity of bacterial and fungal communities displayed a positive linear relationship with soil EC, whereas the activity and diversity of these two microbial groups and SOM displayed a significant quadratic relationship. The finding suggested that microbial community was predominantly influenced by SOM content.
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Akrivos, J., D. Mamais, K. Katsara und A. Andreadakis. „Agricultural utilisation of lime treated sewage sludge“. Water Science and Technology 42, Nr. 9 (01.11.2000): 203–10. http://dx.doi.org/10.2166/wst.2000.0207.

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Over one growing season, lime treated dewatered sludge was applied to pot and field cotton cultivation at rates of 0, 10, 20 and 30 t/ha to determine the effects of sludge agricultural reuse on physical and chemical soil properties, on soil and plant heavy metal content and on plant production. In most cases total N and total and soluble P content of the soil increased with addition of sludge. Maximum pH increase caused by addition of lime treated sludge to alkaline soils did not exceed 0.2. Heavy metal content in all plant tissues and soil samples did not increase significantly as a result of sludge amendment. Plant yields increased significantly with sludge addition for the three alkaline soils used in this study. A low plant productivity observed with one of the soil types studied, was attributed to the high concentration of Ni in the soil and the low nutrient content of the soil.
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Amouei, Abdoliman, Hourieh Fallah, Hosseinali Asgharnia, Abbas Mousapour, Hadi Parsian, Mahmoud Hajiahmadi, Asieh Khalilpour und Hajar Tabarinia. „Comparison of heavy metals contamination and ecological risk between soils enriched with compost and chemical fertilizers in the North of Iran and ecological risk assessment“. Environmental Health Engineering and Management 7, Nr. 1 (17.01.2020): 7–14. http://dx.doi.org/10.34172/ehem.2020.02.

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Background: Nowadays, uncontrolled use of chemical fertilizers in agriculture is one of the reasons for the entry of heavy metals into the environment. In this study, the heavy metals contamination of the soils enriched with compost and chemical fertilizers in the North of Iran and its ecological risk assessment were evaluated. Methods: In this study, 108 soil samples were collected from agricultural soils of some places of Babol in Mazandaran province. An atomic absorption spectrophotometer (PG-990) was used to determine the concentrations of lead, cadmium, and zinc in the soil samples. The assessment of soil contamination was performed by the contamination factor, degree of contamination indices, and the potential ecological risk of the heavy metals. Data were analyzed using SPSS version 22. Descriptive and chi-square tests were used to compare the mean with existing standards. Significant level was considered at P<0.05. Results: The highest lead concentration (35.7 ± 9.5 mg/kg) was observed at 5-cm depth, and the maximum cadmium (1.1 ± 0.2 mg/kg) and zinc (88 ± 22.6 mg/kg) concentrations were observed at 15-cm depth. The results showed that lead, cadmium, and zinc concentrations in the agricultural soils enriched with compost fertilizers were acceptable, but agricultural soils enriched with chemical fertilizers indicated higher content than those enriched with compost fertilizers and higher than the maximum allowable concentration. The maximum contamination degree, pollution index, and potential ecological risk in the agricultural soils enriched with the chemical fertilizers were 15.77, 1.97, and 293.48, respectively, and these soils had low potential pollution and moderate ecological risks. Conclusion: According to the results, it is necessary to use compost fertilizers for the agricultural soils enrichment.
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Hossin, Md Shahin, Alok Kumar Paul, Md Fazlul Hoque, Morsheda Akter Mukta und Md Delower Hossain. „Estimation of Fertility Status of Coastal Soils for Agricultural Planning in Bangladesh“. Haya: The Saudi Journal of Life Sciences 7, Nr. 5 (15.05.2022): 142–50. http://dx.doi.org/10.36348/sjls.2022.v07i05.001.

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A study was conducted to know the fertility status of coastal soils of Bangladesh for agricultural planning. Thirty composite soil samples were collected from different locations of Kalapara upazila under Patuakhali coastal district in Bangladesh with Geographic Positioning System (GPS) positions. The soil samples were analyzed for physical properties (moisture, texture, bulk density, particle density and porosity) and chemical properties (pH, electrical conductivity, total nitrogen, organic carbon, exchangeable sodium, exchangeable potassium, available sulphur and available phosphorus). The range of moisture contents of collected soils was 24 to 29% and the textural class was silty clay. The bulk density ranged from 1.30 to 1.47 gcm-3. The particle density ranged from 2.31 to 2.49 gcm-3. The porosity of soil samples ranging from 40.96 to 46.06%. The pH ranged from 5.85 to 6.45. The EC value of collected soils ranged from 3.10 to 5.12 dSm-1. The total nitrogen and organic carbon content was low to medium. The exchangeable sodium and potassium content of soils ranged from 9.22 to 18.47 meq 100g-1 and 0.16 to 0.27 meq 100g-1, respectively. The available sulphur and phosphorus content of soils ranged from 17.21 to 33.21 mg kg-1 and 17.12 to 33.09 mg kg-1, respectively. The results revealed that the soils of the study area were slightly to moderately saline and thus the nutrients present in the soils were low to medium level. Hence, salinity problem of soils should be considered before agricultural planning in the study area.
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KARA, Zekeriya, Oktay YELMEN und Hatice ÇOKKIZGIN. „Determination of Some Physical Characteristics of Agricultural Soils of Ceyhan Plain“. MAS Journal Of Applied Sciences 7, Nr. 11 (10.03.2022): 139–45. http://dx.doi.org/10.52520/masjaps.212.

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In this study, some physico-chemical properties of the agriculturally produced soils in Adana's Ceyhan plain were determined and their relations with each other were tried to be explained. For this purpose, a total of 46 soil samples were taken from the agricultural production areas in the Ceyhan plain. Field capacity, wilting point, available water, hydraulic conductivity and other routine analyzes of the soil samples taken were done in the laboratory. According to the results; The average pH of the soils (7.73) was slightly alkaline, the total lime (19.06%) was very calcareous, and the salt content (0.15%) was in the slightly salty class. The physical properties of the soils, average clay 37.13%, sand 36.65% and hydraulic conductivity were determined as 0.46 cmh-1. According to the results, it has been observed that the water permeability of the soils of the Ceyhan plain is very low due to the high clay content, and the Ceyhan plain soils were low saline class. In addition, although the field capacity of the studied soils was high, it was determined that the water content suitable for the plant was not high. This can be explained by the high clay content of the plain soils. Organic regulators (such as leonardite, cattle manure) can be applied to improve the light salt problem, water permeability and useful water content of the Ceyhan plain soils.
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Bhavsar, Monika S., Monika Naphade, Rajshri Shinde und Mayuri Deshmukh. „Physico - chemical and micronutrients status of soils of Velhale village Bhusawal tehsil, Jalgaon district Maharashtra, India“. INTERNATIONAL JOURNAL OF PLANT SCIENCES 17, Nr. 1 (15.01.2022): 1–7. http://dx.doi.org/10.15740/has/ijps/17.1/1-7.

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Soil fertility is the quality of soil to supply nutrients in the proper amount for plant growth without causing toxicity and deficiency. Soil fertility management is highly complex given the myriad of interacting factors that dictate the extent to which farming state farms invest in the fertility of their soils. To achieve precision in farming and to maximize crop production, there should be proper maintenance of soil health and minimize fertilizer mis application One hundred farmers were randomly selected from the Velhale Village Bhusawal Tehsil, Jalgaon district Maharashtra through the Soil Health Card Scheme under the Department of Soil Science and Agricultural Chemistry, Dr Ulhas Patil College of Agriculture, Jalgaon Maharashtra to assess the physico-chemical properties, macro and micronutrients status of soils in the year 2019-20. One hundred geo-referenced soil samples (0-20 cm) from Velhale Village Bhusawal were collected and analyzed in the laboratory for soil pH, electrical conductivity, organic carbon content, calcium carbonate content, available macronutrients viz., N, P, K, S and micronutrients like Fe, Zn, Cu, Mn and B.The pH and EC of soils collected from the study area varied from 6.5 to 8.1 and 0.54 to 0.90 dS m-1 showing the neutral to alkaline nature of soil and soils are safe in total soluble salt content and organic carbon content was very low to medium 0.18 to 0.59%, respectively. The results obtained in the present study clearly showed large variability in the chemical properties of soil. The available sulphur varied from (6.92 to18.00 mg kg-1) low to medium. Available iron and zinc content was low to medium (0.50-6.26 and 0.42- 0.79 mg kg-1, respectively) while, copper and manganese content was sufficient (0.31-0.82 and 0.50-4.64 mg kg-1, respectively) across the study area. Available boron in soils of all the tehsil ranged from 0.56to 2.58 mg kg-1 (medium to high). Soil testing plays an important role in the use of fertilizers and other agricultural inputs. Soil test summaries and soilfertility maps are of vital necessity as reference materials for the scientific management of soil. This information could aid in decision making for the application of plant nutrients for higher monetary returns to the farmers.
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Zawierucha, Elżbieta, Monika Skowrońska und Marcin Zawierucha. „Chemical and Biological Properties of Agricultural Soils Located along Communication Routes“. Agriculture 12, Nr. 12 (24.11.2022): 1990. http://dx.doi.org/10.3390/agriculture12121990.

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The aim of the study was to assess the quality of agricultural soils, which accumulate additional amounts of heavy metals from fertilization and modify their bioavailability, with the use of interdependencies between their biological and chemical properties conditioned by the distance from communication routes. Our results indicated that heavy metals had an impact on enzyme activity in soils and their accumulation was significantly related to the distance from the edge of the road, location of sampling sites, date of soil sampling, and years of research. It was found that the greatest amounts of zinc, cadmium, lead, and copper were accumulated at a distance of 5–20 m from the edge of the road. The highest enrichment factor and geoaccumulation index values were recorded for Pb, followed by Zn, Cu, and Cd. Principal component analysis and regression models showed that the activities of phosphatase and dehydrogenases seem to be the best bioindicators of contamination of roadside soils used for agricultural purposes. Since their activity is related to soil’s organic carbon content, inputs of organic fertilizers and crop residues should be ensured in the agroecosystems along roadsides.
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Nadi, M., E. Sedaghati und G. Füleky. „Characterization of organic matter content of Hungarian agricultural soils“. Acta Agronomica Hungarica 60, Nr. 4 (01.12.2012): 357–66. http://dx.doi.org/10.1556/aagr.60.2012.4.6.

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Humic substances have proved to be very important fractions in soils, playing a key role especially in agricultural soil and influencing chemical and physical soil properties. Spectroscopic methods are widely used to identify the quality of soil humic substances. In this study, 16 soil samples were selected from the Soil Bank of the Soil Science Laboratory at Szent István University, Gödöllő. The samples were extracted using the Hot Water Percolation (HWP) method and the amount of dissolved organic carbon (DOC) in each fraction was measured. The kinetics of the DOC extraction process with the HWP method was estimated. The Ultraviolet Visible (UV-VIS) technique was used to characterize the properties of HWP-dissolved organic carbon (HWP-DOC), measuring absorbance at 200–700 nm. Among the humification parameters, the absorbance ratios at 254 and 365 nm (E2/E3) and 465 and 665 nm (E4/E6), the specific UV absorbance (SUVA) and the UV absorbance ratio index (URI) were estimated. The K factor (humus stability coefficient) and E2/E3 and E4/E6 in NaOH and NaF extracts were also measured. The properties of HWP-DOC were similar in most of the soil samples. There was a good correlation between the content of HWP-DOC and the absorbance at 254 nm. URI, SUVA, E2/E3 and E4/E6 indicated that most of the HWP-DOC in the samples consisted of fulvic acid components with greater activity, simpler structure and low molecular weight.
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Kombienou Pocoun Damè. „Physico-chemical characterization of the soils of the watersheds of Boukombe in North-West Benin“. International Journal of Science and Research Archive 1, Nr. 1 (30.11.2020): 035–54. http://dx.doi.org/10.30574/ijsra.2020.1.1.0015.

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This study addresses the specificities of soils in low-income countries. These infertile soils are characterized by low levels of agricultural productivity and the disappearance of long-term fallow, which is gradually giving way to shorter-term fallow and sedentary agriculture. The overall objective was to assess the physico-chemical characteristics of the soils of the Boukombe watersheds in the north-west of Atacora in Benin. Soil studies of 15 farm sites from which soils were sampled at the [0-20] cm horizon with 30 composite samples and statistical analyzes were performed. The results of particle size analysis showed predominance (68%) of a textural dimorphism with a sandy loam character and a relatively stable structure. The soils are generally acidic (pH ≤ 5), sodium in places and poor in Organic Matter (0.3%), particularly in the plateau. Mountain lands have soils richer in OM (4%), but poor in nitrogen with a content of between [0.02-0.14%], the C / N ratio at 3% lower than 12. The contents nutrients and minerals are accumulated at the bottom of slopes (2.23% carbon, 0.14% nitrogen) and at the top of slopes (14ppm of phosphorus) under Fonio. These soils remain in a fragile state, subjecting them to the process of intense erosion. The degradation, silting up and progressive acidification of soils constitute the main constraints of agricultural production, the solution of which is based on restoring their fertility by rehabilitating dikes and removing silt.
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Dissertationen zum Thema "Soils Agricultural chemical content"

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Edvantoro, Bagus Bina. „Bioavailability, toxicity and microbial volatilisation of arsenic in soils from cattle dip sites“. Title page, Contents and Abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09A/09ae24.pdf.

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Taillon, Kate. „Modeling surface complexation relationships in forest and agricultural soil“. Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82435.

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The adsorption behaviour of trace metals in soil may provide us with a way to more accurately predict and assess the toxicity of metals in the environment. This thesis reports efforts to apply surface complexation modeling to agricultural and forest soil and to relate model parameters to common soil properties. This study considered Ca, Cd, Cu, Pb and Zn but the methods here could be applied to other metals. In Chapter 2, the surface charge and adsorption behaviour of a set of Ap horizons was characterised using back-titration and batch adsorption techniques. With the objective of simplifying the application of the NICCA model to surface charge and cation adsorption in whole soils the parameters of the NICCA model were related to soil properties (Chapter 3). Four of the six surface charge parameters could be predicted from soil properties and this enabled me to reasonably predict the surface charge of a second group of soils from soil properties. These results suggest that it is possible to make reasonable predictions about the surface charge and adsorption behaviour of a given type of soil using some easily measurable soil properties and a set of generic NICCA adsorption parameters for that soil type. In Chapter 4 this idea is applied to the determination of lime requirement for the agricultural soils.
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Ahmad, Riaz. „Sorption and release of pesticides in soils : the role of chemical nature of soil organic matter /“. Title page, table of contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09pha2853.pdf.

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Drlíková, Barbora. „Posouzení kvality půdy zpracované klasickým způsobem ve vybrané lokalitě v Olomouckém kraji“. Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265451.

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Diploma thesis documents the problems of soil quality, which is assessed on the basis of physical, chemical or biological indicators of soil quality. The paper describes the various indicators, its methodology and evaluation. In the practical part evaluates the quality of soil cultivated with the traditional way - using plowing. The experimental area, where the samples were taken from the soil, lies in the Olomouc region in the municipality Šumvald. Evaluated were selected physical, chemical and physico-chemical properties of soil, e.g. particle size distribution, bulk density, porosity, air capacity, hydrolimits, pH, carbonates, humus content and salinity of the soil.
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Mallory, Ellen B. „Crop/Livestock Integration Effects on Soil Quality, Crop Production, and Soil Nitrogen Dynamics“. Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/MalloryEB2007.pdf.

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Zhang, Tiequan. „Chemical behavior of phosphorus over time in fertilized soils“. Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34486.

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Fertilizer P accumulates in soils, with potential for movement to waterways, causing eutrophication. Fertilizer P reactions in monoculture corn (Zea mays L.) production over time will determine environmentally sound soil management practices. Soil P changes over time were determined on a Chicot sandy clay loam (Grey Brown Luvisol) and a Ste. Rosalie clay (Humic Gleysol). Fertilizer P was added at 44 and 132 kg P ha$ sp{-1}$ and to the Chicot soil only, manure containing 60 kg P for the first five years. Mehlich-3 (M3) extraction, soil P fractionation, $ sp{31}$P NMR analysis, P in leaching water, and path analysis were measured. Added P increased M3 P more when manure was also added, and in clay soils. To increase M3 P by 1 kg ha$ sp{-1}$ required from 3.6 to 8.1 kg ha$ sp{-1}$ fertilizer P, and when "net" fertilizer additions were used, fertilizer required was from 1.8 to 5.3 kg P ha$ sp{-1}.$ Moderately labile organic P (Po) decreased at 0 added P. With P at the rate of plant removal, inorganic (Pi) and Po fractions were unchanged. Excess P increased labile P and resistant P through moderately labile Pi. More P remained in labile Pi fractions when manure P was added, or in the soil with the higher clay content. Soil organic P levels increased upon fertilization only in the sandy loam soil. Labile and moderately labile Po could be estimated using monoester phosphate values determined by $ sp{31}$P NMR. Inorganic P values in gravitational water increased above 0.05 mg P L$ sp{-1}$ when soil labile Pi increased above 108 mg kg$ sp{-1}$ in the sandy loam soil and 69 mg L$ sp{-1}$ in the clay soil. Thus soil P movement was related to inorganic P additions. Increased fertilizer P did not increase organic P leaching losses. Fertilizer P in corn production may result in groundwater eutrophication.
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Batchily, Abdul Karim 1952. „Use of Chroma Meter color measurements to evaluate the organic carbon, iron, and water content of soils“. Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277947.

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The soil color components of 127 samples from five Arizona Agricultural Research Centers and 52 WEPP samples occurring in various parts of the U.S.A. were evaluated using a Minolta Chroma Meter. This instrument is designed to minimize the variability in color determination utilizing a built-in light source to generate a primary source of radiation. Simple and multiple linear regression equations relating Hue, Value, and Chroma color components were obtained to predict the organic carbon and iron content of these soils. The results show that using global data is less reliable than specific groupings of soils. Moist value and moist chroma moist are the two most important color components in estimating the organic carbon content of soils. Chroma and Hue were highly correlated to iron at all moisture levels. Chroma was least affected by soil moisture, but Value and Hue consistently decreased for all soils.
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Jiang, Zhiyong. „Modeling agricultural chemical transport and fate in soils under controlled water table /“. The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487867541733368.

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Reeves, Alastair Ian. „Contaminant tracking through dendro-chemical analysis of tree-radii“. Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69688.

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The research used dendro-chemical analysis of ash tree rings and current year leaf litter to track Cd, Pb, Zn, Cu, Mn, Cr, and Sn spread and cycling from a closed garbage dump-toxic waste site. This technique allowed for determination of areal extent, contaminant levels and time period of initial contaminant contact. Only Zn, Sn, and Cu were found in elevated quantities in the xylem wood and Pb in the leaf litter. Elemental concentrations of Pb, Sn and Cd in xylem wood and leaves of ash were positively correlated. Tin was the only element to demonstrate a clear initial contact period and elemental accumulation with age. Significant levels of Cu accumulated in the heartwood while Zn revealed significant but inconsistent accumulated patterns. Expected attenuation zones associated with municipal solid waste landfill leachate dispersion were not found; thus the pathway for contaminant dispersion was likely through groundwater flow.
An elemental index was developed to facilitate the use of dendro-chemical analysis in periods of suppressed tree growth resulting from environmental pollution.
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Adrover, Fiol Maria. „Efectes del reg amb aigües residuals tractades en els sols i els cultius“. Doctoral thesis, Universitat de les Illes Balears, 2010. http://hdl.handle.net/10803/9377.

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El reg amb aigües residuals tractades s'ha convertit avui en dia en una necessitat, ja que permet preservar els recursos hídrics de més qualitat i constitueix una alternativa necessària per al manteniment de regadius tradicionals. En aquesta tesi s'avaluen els efectes del reg amb aigües residuals tractades d'origen domèstic sobre les característiques químiques i biològiques de diferents tipologies de sòls a l'illa de Mallorca, així com sobre el creixement dels cultius i la seva composició mineral mitjançant diferents estudis de camp i en cultius en contenidors. En general no s'han apreciat efectes negatius importants causats pel reg amb aquestes aigües excepte alguns valors puntualment més elevats de crom i plom que es relacionen amb aportacions d'aigües poc depurades realitzades en el passat. Segons els resultats obtinguts amb el reg amb aigües residuals tractades d'origen domèstic es contribueix a millorar la qualitat del sòl i s'aporten part dels nutrients que requereixen els cultius per al seu creixement.
El riego con aguas residuales tratadas se ha convertido hoy en día en una necesidad, ya que permite preservar los recursos hídricos de más calidad y constituye una alternativa necesaria para el mantenimiento de regadíos tradicionales. En esta tesis se evalúan los efectos del riego con aguas residuales tratadas de origen doméstico sobre las características químicas i biológicas de diferentes tipologías de suelos en la isla de Mallorca, así como sobre el crecimiento de los cultivos y su composición mineral mediante diferentes estudios de campo i en cultivos en contenedores. En general no se han apreciado efectos negativos importantes causados por el riego con estas aguas, excepto algunos valores puntualmente más elevados de cromo y plomo que se relaciona con aportaciones de aguas poco depuradas realizadas en el pasado. Según los resultados obtenidos con el riego con aguas residuales tratadas de origen doméstico se contribuye a mejorar la calidad del suelo y se aportan parte de los nutrientes que requieren los cultivos para su crecimiento.
Nowadays the irrigation with treated waste water has become a necessity, not only, because it allows preserving fresh water but it also constitutes an important alternative to the maintenance of traditional irrigating lands. Considering different chemical and biological characteristics of soil samples of Mallorca island (Spain), this thesis investigates the effect of irrigation with treated domestic waste water on soil properties. In addition, several studies were conducted in a series of pot experiments and land conditions to monitor the crops growth and evaluate their mineral compositions. In general, no negative effects caused by this type of irrigation have been observed, except of some high values of chromium and lead which were related to past irrigation realized with untreated effluents. According to our results, the irrigation with treated domestic wastewater contributes to improve soil quality and supplies part of the nutrient requirements of the crops.
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Bücher zum Thema "Soils Agricultural chemical content"

1

Sauerbeck, Dieter. Funktionen, Güte und Belastbarkeit des Bodens aus agrikulturchemischer Sicht. Stuttgart: Kohlhammer, 1985.

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Nong tian tu rang pei fei. Beijing: Ke xue chu ban she, 2009.

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3

Regional, Fertilizer Conference (42nd 1991 Coeur d'Alene Idaho). Proceedings Forty Second Annual Regional Fertilizer Conference: Coeur d'Alene Resort, Coeur d'Alene, Idaho, July 7-9, 1991. [Spokane, WA: The Association, 1991.

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4

Baker, B. L. Attenuation of pollutants by Alberta soils. Edmonton: Research Management Division, Alberta Environment, 1985.

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Brown, Kenneth Warren. The stability and mobility of mutagenic activity from wastewater and sludge in agricultural soils. Research Triangle Park, NC: U.S. Environmental Protection Agency, Health Effects Research Laboratory, 1988.

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Brown, Kenneth Warren. The stability and mobility of mutagenic activity from wastewater and sludge in agricultural soils. Research Triangle Park, NC: U.S. Environmental Protection Agency, Health Effects Research Laboratory, 1988.

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R, Leschber, Davis R. D. 1949-, L'Hermite P. 1936- und Commission of the European Communities., Hrsg. Chemical methods for assessing bio-available metals in sludges and soil: Proceedings of a seminar organized by the Commission of the European Communities ... held in Münster, Federal Republic of Germany, 11-13 April 1984. London: Elsevier Applied Science Publishers, 1985.

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Baldwin, Joe A. Ground water and soils reconnaissance of the Lower Payette area, Payette County, Idaho. [Boise]: Idaho Dept. of Health and Welfare, Division of Environmental Quality, 1994.

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F, Führ, Ophoff Holger und Deutsche Forschungsgemeinschaft. Senatskommission zur Beurteilung von Stoffen in der Landwirtschaft., Hrsg. Pesticide bound residues in soil : workshop, September 3rd-4th, 1996. Weinheim: Wiley-VCH, 1998.

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Detroy, Mark G. Occurrence and distribution of nitrate and herbicides in the Iowa River alluvial aquifer, Iowa--May 1984 to November 1985. Iowa City, Iowa: Dept. of the Interior, U.S. Geological Survey, 1989.

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Mehr Quellen

Buchteile zum Thema "Soils Agricultural chemical content"

1

Bell, Michael J., Michael L. Thompson und Philip W. Moody. „Using Soil Tests to Evaluate Plant Availability of Potassium in Soils“. In Improving Potassium Recommendations for Agricultural Crops, 191–218. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_8.

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AbstractThe purpose of this chapter is to describe how bioavailable soil K is assessed or predicted by soil tests. Soil testing commonly refers to the collection of a sample of soil representative of a field or agronomic management unit and, by way of extraction using chemical reagents, determination of the quantity of a nutrient that can be related to plant uptake or yield. Normally only a small fraction of the total quantity of the nutrient present in the soil is extracted during the procedure, but if that amount can be correlated with actual crop uptake or overall crop productivity, then the soil test is deemed to have useful predictive power.Soil tests are routinely used to guide applications of fertilizer to soil so that crop demand for nutrients can be met effectively and economically. Here, we summarize the procedures involved in collecting a representative soil sample for K analysis, outline how that sample should be prepared for laboratory analysis, highlight the principles and mode of action of routine soil tests, and explore some common issues that may confound the correlation between a soil K test result and plant K acquisition or crop yield. Soil testing methods are discussed in the context of their relationship to the different forms of soil K and the in-soil chemical processes that may change these forms into K that can be taken up by roots.
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Rosolem, Ciro A., Antonio P. Mallarino und Thiago A. R. Nogueira. „Considerations for Unharvested Plant Potassium“. In Improving Potassium Recommendations for Agricultural Crops, 147–62. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_6.

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AbstractPotassium (K) is found in plants as a free ion or in weak complexes. It is easily released from living or decomposing tissues, and it should be considered in fertilization programs. Several factors affect K cycling in agroecosystems, including soil and fertilizer K contributions, plant K content and exports, mineralization rates from residues, soil chemical reactions, rainfall, and time. Soil K+ ions can be leached, remain as exchangeable K, or migrate to non-exchangeable forms. Crop rotations that include vigorous, deep-rooted cover crops capable of exploring non-exchangeable K in soil are an effective strategy for recycling K and can prevent leaching below the rooting zone in light-textured soils. The amount of K released by cover crops depends on biomass production. Potassium recycled with non-harvested components of crops also varies greatly. Research with maize, soybean, and wheat has shown that 50–60% of K accumulated in vegetative tissues is released within 40–45 days. A better understanding of K cycling would greatly improve the efficacy of K management for crop production. When studying K cycling in agricultural systems, it is important to consider: (1) K addition from fertilizers and organic amendments; (2) K left in residues; (3) K partitioning differences among species; (4) soil texture; (5) soil pools that act as temporary sources or sinks for K. In this chapter, the role of cash and cover crops and organic residues on K cycling are explored to better understand how these factors could be integrated into making K fertilizer recommendations.
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Kuria, Peter, Josiah Gitari, Saidi Mkomwa und Peter Waweru. „Effect of conservation agriculture on soil properties and maize grain yield in the semi-arid Laikipia county, Kenya.“ In Conservation agriculture in Africa: climate smart agricultural development, 256–69. Wallingford: CABI, 2022. http://dx.doi.org/10.1079/9781789245745.0015.

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Abstract Low and unreliable rainfall, along with poor soil health, is a main constraint to maize production in the semi-arid parts of Kenya that account for over 79% of the country's land area. In the vast county of Laikipia, farmers continue to plant maize despite the predominantly low quantities of precipitation. Participatory farmer experimentation with Conservation Agriculture (CA) was undertaken for six consecutive growing seasons between July 2013 and December 2016 to determine the effectiveness of CA as a method of improving soil properties and enhancing maize yields with the limited rainfall quantities received in these parts of Kenya. The main CA practices tested include chisel tine furrow opening (ripping) and live legume (Lablab purpureus) cover crop, as well as maize stover mulches, all implemented under varying inorganic fertilizer rates. The research was done across 12 administrative locations of Laikipia County where soils are mainly Phaeozems and Vertisols with a clay-loam texture. The research design used was researcher-designed and farmer-managed. In each of the 12 trial sites, participatory farmers' assessments and field days were carried out as a way of outreach to the bigger farming communities around the trial sites. The research findings obtained demonstrated that the use of CA impacts positively on soil properties and is a viable practice for enhancing maize yields in these moisture deficit-prone parts of the country. Soil chemical analysis assessment results showed that CA impacted positively on a number of soil mineral components including organic carbon, total nitrogen, phosphorus, potassium, calcium and pH. Midseason chlorophyll content assessment of the maize crop showed that there was good response to fertilizer application, as well as to mulching with crop residues for soil cover. Maize grain yield data also showed that the use of a CA package comprising chisel tine ripping combined with mulching by plant residues and use of mineral fertilizer resulted in a two- to threefold increase in grain yields above the farmer practice control. Mean maize grain yield in farmer practice plots was 1067 kg ha-1 compared with the CA-treated plot with mineral fertilization that yielded 2192 kg ha-1.
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Spaccini, Riccardo, und Alessandro Piccolo. „Carbon Sequestration in Soils by Hydrophobic Protection and In Situ Catalyzed Photo-Polymerization of Soil Organic Matter (SOM): Chemical and Physical–Chemical Aspects of SOM in Field Plots“. In Carbon Sequestration in Agricultural Soils, 61–105. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-23385-2_4.

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Astover, Alar, Lech Wojciech Szajdak und Raimo Kõlli. „Impact of Long-Term Agricultural Management and Native Forest Ecosystem on the Chemical and Biochemical Properties of Retisols’ Organic Matter“. In Bioactive Compounds in Agricultural Soils, 149–71. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43107-9_7.

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Zhang, Zhongqiang. „Contents of five heavy metals in agricultural land soil in Hengshui and ecological risk assessment“. In Energy Revolution and Chemical Research, 440–44. London: CRC Press, 2022. http://dx.doi.org/10.1201/9781003332657-61.

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Jones, K. C., J. A. Stratford, K. S. Waterhouse und A. E. Johnston. „Long-Term Changes in the Polynuclear Aromatic Hydrocarbon Content of Agricultural Soils“. In Air Pollution and Ecosystems, 792–97. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-4003-1_98.

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Erviö, R., R. Mäkelä-Kurtto und J. Sippola. „Chemical Characteristics of Finnish Agricultural Soils in 1974 and in 1987“. In Acidification in Finland, 217–34. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75450-0_11.

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Gómez-Díaz, Jesús D., Alejandro I. Monterroso-Rivas, Lizeth M. Lechuga-Gayosso, Antonio R. Arce-Romero und Patricia Ruiz-Gracia. „Impact of Climate Change on Soil Organic Carbon Content on Agricultural Soils of Mexico“. In Advances in Intelligent Systems and Computing, 58–69. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-70187-5_5.

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He, Zhongqi, und Mingchu Zhang. „Structural and Functional Comparison of Mobile and Recalcitrant Humic Fractions from Agricultural Soils“. In Labile Organic Matter-Chemical Compositions, Function, and Significance in Soil and the Environment, 79–98. Madison, WI, USA: Soil Science Society of America, Inc., 2015. http://dx.doi.org/10.2136/sssaspecpub62.2014.0036.

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Konferenzberichte zum Thema "Soils Agricultural chemical content"

1

Drovovozova, T. I., S. A. Marias, E. S. Kulakova und N. N. Panenko. „GEOECOLOGICAL CYCLES OF SALT-FORMING IONS IN AGRICULTURAL LANDSCAPES“. In STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS. DSTU-PRINT, 2020. http://dx.doi.org/10.23947/interagro.2020.1.509-513.

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The analysis of the chemical composition of natural water bodies-receivers of drainage and discharge waters. It is shown that the background concentrations of salt-forming ions in water bodies exceed the Mpcrx, which indicates the dominant influence of surface runoff from the entire catchment area and underground feeding by mineralized sulphate groundwater on the formation of the quality of the water environment. The chemical composition of water extract from the soil from irrigated areas adjacent to reservoirs was studied on the example of semikarakorsky district of the Rostov region. The classification of irrigated soils (0-20 cm) adjacent to the reservoirs, the degree and type of salinity depending on the chemistry of salts, which showed that agricultural activity is accompanied by a transformation of the geo-ecological cycles of salt-ions, leading to soil salinization, increase of mineralization of drainage runoff and, as a consequence, water of small streams. Based on the study of the chemical composition of natural, groundwater and water quality in reservoirs, and soil adjacent to sewers the features of dynamics of the content of salt ions and the intensity of their migration in agroecosystems.
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Stojic, Natasa, Mira Pucarevic, Milica Živkovic, Vesna Teofilovic und Dunja Prokic. „UTICAJ OTPADA NA FIZIČKO-HEMIJSKE KARAKTERISTIKE ZEMLJIŠTA“. In XXVI savetovanje o biotehnologiji sa međunarodnim učešćem. University of Kragujevac, Faculty of Agronomy, 2021. http://dx.doi.org/10.46793/sbt26.351s.

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Land exploitation directly affects the physico-chemical characteristics of the soil. Agricultural land can often be seen near the landfills. The question is how much waste affects the production potential of land. The research in this paper is focused on the influence of the municipal waste landfill on the physico-chemical characteristics of the soil. In soil samples were analyzed: pH in KCl, pH in H2O, CaCO3, humus, total nitrogen, P2O5, K2O and organic carbon. The obtained results indicate a negative impact of waste on the content of OC and the content of easily accessible phosphorus and potassium.
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Angelova, Violina. „HEAVY METAL ACCUMULATION AND CHEMICAL COMPOSITION OF ESSENTIAL OILS OF LEMON BALM (MELISSA OFFICINALIS L.) CULTIVATED ON HEAVY METAL CONTAMINATED SOILS“. In Fourth International Scientific Conference ITEMA Recent Advances in Information Technology, Tourism, Economics, Management and Agriculture. Association of Economists and Managers of the Balkans, Belgrade, Serbia, 2020. http://dx.doi.org/10.31410/itema.2020.287.

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Comparative research has been conducted to allow us to determine the content of heavy metals and chemical composition of lemon balm oils, as well as to identify the possibility of lemon balm growth on soils contaminated by heavy metals. The experimental plots were situated at different distances of 0.5 km, and 15 km, respectively, from the source of pollution the Non-Ferrous-Metal Works (MFMW) near Plovdiv, Bulgaria. On reaching the flowering stage the lemon balm plants were gathered. The content of heavy metals in leaves of lemon balm was determined by ICP. The essential oils of the lemon balm were obtained by steam distillation in laboratory conditions which were analyzed for heavy metals and chemical composition was determined. Lemon balm is a plant that is tolerant to heavy metals and can be grown on contaminated soils. Heavy metals do not affect the development of lemon balm and the quality and quantity of oil obtained from it. Forty components were identified in the oils. The quantity of identified compounds corresponds to 98.82-98.83% of the total oil content. Among the detected compounds, beta-citral (neral) (19.31-20.78%), alfa-citral (geranial) (18,65-19,12%), β-caryophyllene (14.76-16.28%), α-cadinol (3.88-4.74%), geranyl acetate (3.49-3.59%), trans-geraniol (3.40-3.51%), germacrene (3.18-3.28%), citronellal (2.94-3.03%), nerol (2.63-2.71%), neryl acetate (2.42 -2.49%) were the major compounds. The essential oil of Melissa officinalis L. can be a valuable product for farmers from polluted regions.
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Cernat, Sorina, Iulia Nitu und Loredana Beatrice Neagu Frasin. „Research on the Soil-Plant-Fertilizer Interaction in the Main Field Crops“. In G.I.D.T.P. 2019 - Globalization, Innovation and Development, Trends and Prospects 2019. LUMEN Publishing, 2022. http://dx.doi.org/10.18662//lumproc/gidtp2022/02.

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In the context of world agriculture, the application of chemical fertilizers remains one of the main ways to increase agricultural production, manage crop quality and improve soil fertility. The application of cultivation technologies, meant to lead to the improvement of agricultural production, determines biological, chemical, physiological changes in the plant and in the soil.
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Prof. John O Ohu, Prof. Eli E Mamman und Abubakar A Mustapha. „CRITICAL MOISTURE CONTENT OF COMPACTED AGRICULTURAL SOILS WITH VARYING ORGANIC MATTER CONTENT“. In 2013 Kansas City, Missouri, July 21 - July 24, 2013. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2013. http://dx.doi.org/10.13031/aim.20131619229.

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Bugheanu, D., und C. Iacob. „Relating Magnetic Susceptibility and Organic Matter Content in Agricultural Soils“. In 75th EAGE Conference and Exhibition incorporating SPE EUROPEC 2013. Netherlands: EAGE Publications BV, 2013. http://dx.doi.org/10.3997/2214-4609.20131063.

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Cheverdin, Yu I., T. V. Titova und V. A. Bespalov. „THE CONTENT OF EXCHANGEABLE POTASSIUM IN HYDROMORPHIC SOILS OF KAMENNAYA STEPPE“. In «Breeding, seed production, cultivation technology and processing of agricultural crops». Federal State Budgetary Scientific Institution Federal Scientific Rice Centre, 2021. http://dx.doi.org/10.33775/conf-2021-317-320.

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„Quality Evaluation and Physico-Chemical Properties of Soils around a Cement Factory in Gombe State, Nigeria“. In International Conference on Advances in Agricultural, Biological & Environmental Sciences. International Institute of Chemical, Biological & Environmental Engineering, 2014. http://dx.doi.org/10.15242/iicbe.c1014123.

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Nawaz, Rab, Hathairatana Garivait und Patana Anurakpongsatorn. „Impacts of precipitation on leaching behavior of plant nutrients in agricultural soils of the tropics“. In 2010 2nd International Conference on Chemical, Biological and Environmental Engineering (ICBEE). IEEE, 2010. http://dx.doi.org/10.1109/icbee.2010.5651678.

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„Health Risk Assessment of Selected Wild Valuable Plants Species Grown around Amaozara and Amaechara Aged Dumpsite Soils in Amasiri, Afikpo North L.G.A. of Ebonyi State, Nigeria“. In 3rd International Conference on Chemical, Agricultural and Medical Sciences. International Institute of Chemical, Biological & Environmental Engineering, 2015. http://dx.doi.org/10.15242/iicbe.c1215029.

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Berichte der Organisationen zum Thema "Soils Agricultural chemical content"

1

Or, Dani, Shmulik Friedman und Jeanette Norton. Physical processes affecting microbial habitats and activity in unsaturated agricultural soils. United States Department of Agriculture, Oktober 2002. http://dx.doi.org/10.32747/2002.7587239.bard.

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experimental methods for quantifying effects of water content and other dynamic environmental factors on bacterial growth in partially-saturated soils. Towards this end we reviewed critically the relevant scientific literature and performed theoretical and experimental studies of bacterial growth and activity in modeled, idealized and real unsaturated soils. The natural wetting-drying cycles common to agricultural soils affect water content and liquid organization resulting in fragmentation of aquatic habitats and limit hydraulic connections. Consequently, substrate diffusion pathways to soil microbial communities become limiting and reduce nutrient fluxes, microbial growth, and mobility. Key elements that govern the extent and manifestation of such ubiquitous interactions include characteristics of diffusion pathways and pore space, the timing, duration, and extent of environmental perturbations, the nature of microbiological adjustments (short-term and longterm), and spatial distribution and properties of EPS clusters (microcolonies). Of these key elements we have chosen to focus on a manageable subset namely on modeling microbial growth and coexistence on simple rough surfaces, and experiments on bacterial growth in variably saturated sand samples and columns. Our extensive review paper providing a definitive “snap-shot” of present scientific understanding of microbial behavior in unsaturated soils revealed a lack of modeling tools that are essential for enhanced predictability of microbial processes in soils. We therefore embarked on two pronged approach of development of simple microbial growth models based on diffusion-reaction principles to incorporate key controls for microbial activity in soils such as diffusion coefficients and temporal variations in soil water content (and related substrate diffusion rates), and development of new methodologies in support of experiments on microbial growth in simple and observable porous media under controlled water status conditions. Experimental efforts led to a series of microbial growth experiments in granular media under variable saturation and ambient conditions, and introduction of atomic force microscopy (AFM) and confocal scanning laser microscopy (CSLM) to study cell size, morphology and multi-cell arrangement at a high resolution from growth experiments in various porous media. The modeling efforts elucidated important links between unsaturated conditions and microbial coexistence which is believed to support the unparallel diversity found in soils. We examined the role of spatial and temporal variation in hydration conditions (such as exist in agricultural soils) on local growth rates and on interactions between two competing microbial species. Interestingly, the complexity of soil spaces and aquatic niches are necessary for supporting a rich microbial diversity and the wide array of microbial functions in unsaturated soils. This project supported collaboration between soil physicists and soil microbiologist that is absolutely essential for making progress in both disciplines. It provided a few basic tools (models, parameterization) for guiding future experiments and for gathering key information necessary for prediction of biological processes in agricultural soils. The project sparked a series of ongoing studies (at DTU and EPFL and in the ARO) into effects of soil hydration dynamics on microbial survival strategy under short term and prolonged desiccation (important for general scientific and agricultural applications).
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Waganet, R. J., John Duxbury, Uri Mingelgrin, John Hutson und Zev Gerstl. Consequences of Nonequilibrium Pesticide Fate Processes on Probability of Leaching from Agricultural Lands. United States Department of Agriculture, Januar 1994. http://dx.doi.org/10.32747/1994.7568769.bard.

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Pesticide leaching in heterogeneous field soils is relatively unstudied and is the focus of this project. A wide variety of heterogeneous soils exist, characterized by processes that result from the presence of structural cracks, worm holes, and other preferred pathways within which the majority of transport can occur (called physical non-equilibrium processes), along with the presence of sorption processes that are both equilibrium and kinetic (chemical non-equilibrium processes). Previous studies of pesticide leaching have focused primarily on relatively homogeneous soils, which are less widely distributed in nature, but more studied due to the relative ease with which quantitative theory can be applied to interpret experimental results. The objectives of the proposed project were: first, to gain greater insight into the basic physical and chemical processes that characterize non-equilibrium systems, second, to improve our ability to predict pesticide leaching in heterogeneous field soils, and third, to estimate the consequences of non-equilibrium processes at the field scale by conducting an analysis of the probability of pesticide leaching when non-equilibrium processes prevail. The laboratory, theoretical and modelling aspects of the project were successful; the field aspects less so. We gained greater insight into basic processes in heterogeneous field soils, and we improved and tested tools (simulation models) and the methodology of using such tools for assessing the probability of pesticide leaching as a contribution to broader risk analysis efforts.
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Савосько, Василь Миколайович, Олександр Подоляк, Ірина Олександрівна Комарова und Олексій Карпенко. Modern Environmental Technologies of Healthy Soils Contaminated by Heavy Metals and Radionuclides. E3S Web of Conferences, 2020. http://dx.doi.org/10.31812/123456789/3784.

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Object of research: to systematize (taking into account the possible consequences to biosphere) the known technologies for ecological restoration of soils contaminated by heavy metals and radionuclides. Only a healing technology should be recognized as one possible methodology for solving any soil problems. For soils contaminated by heavy metals and radionuclides healing patterns is conceptually ordered into the following levels: mission, strategy, technology. The mission of healthy soil should be aimed at maintaining the chemical elements content within the optimum interval. The strategy of healthy soil involves the regulation of individual elements content in the soil. Ex-situ a soil healing technology is implemented outside the original pollution site. In-situ, a soil healing technology is carried out directly on the original pollution site. Excavation of the сontaminated soil layer is the first stage for ex-situ soil restoration. In the future it will be possible: 1) storage of contaminated soil at special landfills, 2) treatment of contaminated soil at a special reactor. All technologies for in-situ healthy of heavy metals contaminated soils can be ordered as: 1) localization, 2) deconcentration, 3) inactivation, 4) extraction.
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Belkin, Shimshon, Sylvia Daunert und Mona Wells. Whole-Cell Biosensor Panel for Agricultural Endocrine Disruptors. United States Department of Agriculture, Dezember 2010. http://dx.doi.org/10.32747/2010.7696542.bard.

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Objectives: The overall objective as defined in the approved proposal was the development of a whole-cell sensor panel for the detection of endocrine disruption activities of agriculturally relevant chemicals. To achieve this goal several specific objectives were outlined: (a) The development of new genetically engineered wholecell sensor strains; (b) the combination of multiple strains into a single sensor panel to effect multiple response modes; (c) development of a computerized algorithm to analyze the panel responses; (d) laboratory testing and calibration; (e) field testing. In the course of the project, mostly due to the change in the US partner, three modifications were introduced to the original objectives: (a) the scope of the project was expanded to include pharmaceuticals (with a focus on antibiotics) in addition to endocrine disrupting chemicals, (b) the computerized algorithm was not fully developed and (c) the field test was not carried out. Background: Chemical agents, such as pesticides applied at inappropriate levels, may compromise water quality or contaminate soils and hence threaten human populations. In recent years, two classes of compounds have been increasingly implicated as emerging risks in agriculturally-related pollution: endocrine disrupting compounds (EDCs) and pharmaceuticals. The latter group may reach the environment by the use of wastewater effluents, whereas many pesticides have been implicated as EDCs. Both groups pose a threat in proportion to their bioavailability, since that which is biounavailable or can be rendered so is a priori not a threat; bioavailability, in turn, is mediated by complex matrices such as soils. Genetically engineered biosensor bacteria hold great promise for sensing bioavailability because the sensor is a live soil- and water-compatible organism with biological response dynamics, and because its response can be genetically “tailored” to report on general toxicity, on bioavailability, and on the presence of specific classes of toxicants. In the present project we have developed a bacterial-based sensor panel incorporating multiple strains of genetically engineered biosensors for the purpose of detecting different types of biological effects. The overall objective as defined in the approved proposal was the development of a whole-cell sensor panel for the detection of endocrine disruption activities of agriculturally relevant chemicals. To achieve this goal several specific objectives were outlined: (a) The development of new genetically engineered wholecell sensor strains; (b) the combination of multiple strains into a single sensor panel to effect multiple response modes; (c) development of a computerized algorithm to analyze the panel responses; (d) laboratory testing and calibration; (e) field testing. In the course of the project, mostly due to the change in the US partner, three modifications were introduced to the original objectives: (a) the scope of the project was expanded to include pharmaceuticals (with a focus on antibiotics) in addition to endocrine disrupting chemicals, (b) the computerized algorithm was not fully developed and (c) the field test was not carried out. Major achievements: (a) construction of innovative bacterial sensor strains for accurate and sensitive detection of agriculturally-relevant pollutants, with a focus on endocrine disrupting compounds (UK and HUJ) and antibiotics (HUJ); (b) optimization of methods for long-term preservation of the reporter bacteria, either by direct deposition on solid surfaces (HUJ) or by the construction of spore-forming Bacillus-based sensors (UK); (c) partial development of a computerized algorithm for the analysis of sensor panel responses. Implications: The sensor panel developed in the course of the project was shown to be applicable for the detection of a broad range of antibiotics and EDCs. Following a suitable development phase, the panel will be ready for testing in an agricultural environment, as an innovative tool for assessing the environmental impacts of EDCs and pharmaceuticals. Furthermore, while the current study relates directly to issues of water quality and soil health, its implications are much broader, with potential uses is risk-based assessment related to the clinical, pharmaceutical, and chemical industries as well as to homeland security.
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Banin, Amos, Joseph Stucki und Joel Kostka. Redox Processes in Soils Irrigated with Reclaimed Sewage Effluents: Field Cycles and Basic Mechanism. United States Department of Agriculture, Juli 2004. http://dx.doi.org/10.32747/2004.7695870.bard.

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The overall objectives of the project were: (a) To measure and study in situ the effect of irrigation with reclaimed sewage effluents on redox processes and related chemical dynamics in soil profiles of agricultural fields. (b) To study under controlled conditions the kinetics and equilibrium states of selected processes that affect redox conditions in field soils or that are effected by them. Specifically, these include the effects on heavy metals sorption and desorption, and the effect on pesticide degradation. On the basis of the initial results from the field study, increased effort was devoted to clarifying and quantifying the effects of plants and water regime on the soil's redox potential while the study of heavy metals sorption was limited. The use of reclaimed sewage effluents as agricultural irrigation water is increasing at a significant rate. The relatively high levels of suspended and, especially, dissolved organic matter and nitrogen in effluents may affect the redox regime in field soils irrigated with them. In turn, the changes in redox regime may affect, among other parameters, the organic matter and nitrogen dynamics of the root zone and trace organic decomposition processes. Detailed data of the redox potential regime in field plots is lacking, and the detailed mechanisms of its control are obscure and not quantified. The study established the feasibility of long-term, non-disturbing monitoring of redox potential regime in field soils. This may enable to manage soil redox under conditions of continued inputs of wastewater. The importance of controlling the degree of wastewater treatment, particularly of adding ultrafiltration steps and/or tertiary treatment, may be assessed based on these and similar results. Low redox potential was measured in a field site (Site A, KibutzGivat Brenner), that has been irrigated with effluents for 30 years and was used for 15 years for continuous commercial sod production. A permanently reduced horizon (Time weighted averaged pe= 0.33±3.0) was found in this site at the 15 cm depth throughout the measurement period of 10 months. A drastic cultivation intervention, involving prolonged drying and deep plowing operations may be required to reclaim such soils. Site B, characterized by a loamy texture, irrigated with tap water for about 20 years was oxidized (Time weighted average pe=8.1±1.0) throughout the measurement period. Iron in the solid phases of the Givat Brenner soils is chemically-reduced by irrigation. Reduced Fe in these soils causes a change in reactivity toward the pesticide oxamyl, which has been determined to be both cytotoxic and genotoxic to mammalian cells. Reaction of oxamyl with reduced-Fe clay minerals dramatically decreases its cytotoxicity and genotoxicity to mammalian cells. Some other pesticides are affected in the same manner, whereas others are affected in the opposite direction (become more cyto- and genotoxic). Iron-reducing bacteria (FeRB) are abundant in the Givat Brenner soils. FeRB are capable of coupling the oxidation of small molecular weight carbon compounds (fermentation products) to the respiration of iron under anoxic conditions, such as those that occur under flooded soil conditions. FeRB from these soils utilize a variety of Fe forms, including Fe-containing clay minerals, as the sole electron acceptor. Daily cycles of the soil redox potential were discovered and documented in controlled-conditions lysimeter experiments. In the oxic range (pe=12-8) soil redox potential cycling is attributed to the effect of the daily temperature cycle on the equilibrium constant of the oxygenation reaction of H⁺ to form H₂O, and is observed under both effluent and freshwater irrigation. The presence of plants affects considerably the redox potential regime of soils. Redox potential cycling coupled to the irrigation cycles is observed when the soil becomes anoxic and the redox potential is controlled by the Fe(III)/Fe(II) redox couple. This is particularly seen when plants are grown. Re-oxidation of the soil after soil drying at the end of an irrigation cycle is affected to some degree by the water quality. Surprisingly, the results suggest that under certain conditions recovery is less pronounced in the freshwater irrigated soils.
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Friedman, Shmuel, Jon Wraith und Dani Or. Geometrical Considerations and Interfacial Processes Affecting Electromagnetic Measurement of Soil Water Content by TDR and Remote Sensing Methods. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7580679.bard.

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Time Domain Reflectometry (TDR) and other in-situ and remote sensing dielectric methods for determining the soil water content had become standard in both research and practice in the last two decades. Limitations of existing dielectric methods in some soils, and introduction of new agricultural measurement devices or approaches based on soil dielectric properties mandate improved understanding of the relationship between the measured effective permittivity (dielectric constant) and the soil water content. Mounting evidence indicates that consideration must be given not only to the volume fractions of soil constituents, as most mixing models assume, but also to soil attributes and ambient temperature in order to reduce errors in interpreting measured effective permittivities. The major objective of the present research project was to investigate the effects of the soil geometrical attributes and interfacial processes (bound water) on the effective permittivity of the soil, and to develop a theoretical frame for improved, soil-specific effective permittivity- water content calibration curves, which are based on easily attainable soil properties. After initializing the experimental investigation of the effective permittivity - water content relationship, we realized that the first step for water content determination by the Time Domain Reflectometry (TDR) method, namely, the TDR measurement of the soil effective permittivity still requires standardization and improvement, and we also made more efforts than originally planned towards this objective. The findings of the BARD project, related to these two consequential steps involved in TDR measurement of the soil water content, are expected to improve the accuracy of soil water content determination by existing in-situ and remote sensing dielectric methods and to help evaluate new water content sensors based on soil electrical properties. A more precise water content determination is expected to result in reduced irrigation levels, a matter which is beneficial first to American and Israeli farmers, and also to hydrologists and environmentalists dealing with production and assessment of contamination hazards of this progressively more precious natural resource. The improved understanding of the way the soil geometrical attributes affect its effective permittivity is expected to contribute to our understanding and predicting capability of other, related soil transport properties such as electrical and thermal conductivity, and diffusion coefficients of solutes and gas molecules. In addition, to the originally planned research activities we also investigated other related problems and made many contributions of short and longer terms benefits. These efforts include: Developing a method and a special TDR probe for using TDR systems to determine also the soil's matric potential; Developing a methodology for utilizing the thermodielectric effect, namely, the variation of the soil's effective permittivity with temperature, to evaluate its specific surface area; Developing a simple method for characterizing particle shape by measuring the repose angle of a granular material avalanching in water; Measurements and characterization of the pore scale, saturation degree - dependent anisotropy factor for electrical and hydraulic conductivities; Studying the dielectric properties of cereal grains towards improved determination of their water content. A reliable evaluation of the soil textural attributes (e.g. the specific surface area mentioned above) and its water content is essential for intensive irrigation and fertilization processes and within extensive precision agriculture management. The findings of the present research project are expected to improve the determination of cereal grain water content by on-line dielectric methods. A precise evaluation of grain water content is essential for pricing and evaluation of drying-before-storage requirements, issues involving energy savings and commercial aspects of major economic importance to the American agriculture. The results and methodologies developed within the above mentioned side studies are expected to be beneficial to also other industrial and environmental practices requiring the water content determination and characterization of granular materials.
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Akinleye, Taiwo, Idil Deniz Akin, Amanda Hohner, Indranil Chowdhury, Richards Watts, Xianming Shi, Brendan Dutmer, James Mueller und Will Moody. Evaluation of Electrochemical Treatment for Removal of Arsenic and Manganese from Field Soil. Illinois Center for Transportation, Juni 2021. http://dx.doi.org/10.36501/0197-9191/21-019.

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Soils containing inorganic compounds are frequently encountered by transportation agencies during construction within the right-of-way, and they pose a threat to human health and the environment. As a result, construction activities may experience project delays and increased costs associated with management of inorganic compounds containing soils required to meet environmental regulations. Recalcitrance of metal-contaminated soils toward conventional treatment technologies is exacerbated in clay or organic content-rich fine-grained soils with low permeability and high sorption capacity because of increased treatment complexity, cost, and duration. The objective of this study was to develop an accelerated in situ electrochemical treatment approach to extract inorganic compounds from fine-grained soils, with the treatment time comparable to excavation and off-site disposal. Three reactor experiments were conducted on samples collected from two borehole locations from a field site in Illinois that contained arsenic (As)(~7.4 mg/kg) and manganese (Mn)(~700 mg/kg). A combination of hydrogen peroxide (H2O2) and/or citrate buffer solution was used to treat the soils. A low-intensity electrical field was applied to soil samples using a bench-scale reactor that resembles field-scale in situ electrochemical systems. For the treatment using 10% H2O2 and citrate buffer solution, average removal of 23% and 8% were achieved for Mn and As, respectively. With 4% H2O2 and citrate buffer, 39% and 24% removal were achieved for Mn and As; while using only citrate buffer as the electrolyte, 49% and 9% removal were achieved for Mn and As, respectively. All chemical regimes adopted in this study reduced the inorganic compound concentrations to below the maximum allowable concentration for Illinois as specified by the Illinois Environmental Protection Agency. The results from this work indicate that electrochemical systems that leverage low concentrations of hydrogen peroxide and citrate buffer can be effective for remediating soils containing manganese and arsenic.
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Chefetz, Benny, und Baoshan Xing. Sorption of hydrophobic pesticides to aliphatic components of soil organic matter. United States Department of Agriculture, 2003. http://dx.doi.org/10.32747/2003.7587241.bard.

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Sorption of hydrophobic compounds to aliphatic components of soil organic matter (SOM) is poorly understood even though these aliphatic carbons are a major fraction of SOM. The main source of aliphatic compounds in SOM is above- and below-ground plant cuticular materials (cutin, cutan and suberin). As decomposition proceeds, these aliphatic moieties tend to accumulate in soils. Therefore, if we consider that cuticular material contributes significantly to SOM, we can hypothesize that the cuticular materials play an important role in the sorption processes of hydrophobic compounds (including pesticides) in soils, which has not yet been studied. The overall goal of this research was to illustrate the mechanism and significance of the refractory aliphatic structures of SOM in sorbing hydrophobic compounds (nonionic and weakly polar pesticides). The importance of this study is related to our ability to demonstrate the sorption relationship between key pesticides and an important fraction of SOM. The specific objectives of the project were: (1) To isolate and characterize cuticular fractions from selected plants; (2) To investigate the sorption mechanism of key hydrophobic pesticides and model compounds to cuticular plant materials; (3) To examine the sorption mechanisms at the molecular level using spectroscopic techniques; (4) To investigate the sorption of key hydrophobic pesticides to synthetic polymers; (5) To evaluate the content of cuticular materials in agricultural soils; and (6) To study the effect of incubation of plant cuticular materials in soils on their sorptive capabilities. This project demonstrates the markedly high sorption capacity of various plant cuticular fractions for hydrophobic organic compounds (HOCs) and polar organic pollutants. Both cutin (the main polymer of the cuticle) and cutan biopolymers exhibit high sorption capability even though both sorbents are highly aliphatic in nature. Sorption by plant cuticular matter occurs via hydrophobic interactions and H-bonding interactions with polar sorbates. The cutin biopolymer seems to facilitate reversible and noncompetitive sorption, probably due to its rubbery nature. On the other hand, the epicuticular waxes facilitate enhance desorption in a bi-solute system. These processes are possibly related to phase transition (melting) of the waxes that occur in the presence of high solute loading. Moreover, our data highlight the significance of polarity and accessibility of organic matter in the uptake of nonpolar and polar organic pollutants by regulating the compatibility of sorbate to sorbent. In summary, our data collected in the BARD project suggest that both cutin and cutan play important roles in the sorption of HOCs in soils; however, with decomposition the more condensed structure of the cutin and mainly the cutan biopolymer dominated sorption to the cuticle residues. Since cutin and cutan have been identified as part of SOM and humic substances, it is suggested that retention of HOCs in soils is also controlled by these aliphatic domains and not only by the aromaticrich fractions of SOM.
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Савосько, Василь Миколайович, Юлія Бєлик und Юрій Васильович Лихолат. Ecological and Geological Determination of the Initial Pedogenesis on Devastated Lands in the Kryvyi Rih Iron Mining & Metallurgical District (Ukraine). Journ. Geol. Geograph. Geoecology, 2019. http://dx.doi.org/10.31812/123456789/3643.

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In our time, a very urgent problem is the cessation of negative impacts on the environment and the return to the practical use of the territories of devastated lands. In this regard, it is important to find out the basic laws of primary soil formation in the area of these man-made neoplasms. The initial soil formation conditions were analyzed on 19 experimental sites which represent the main varieties of devastated land in the Kryvyi Rih Iron Mining and Metallurgical District (Central Ukraine): (i) waste rock dumps of old iron mines (old name “Forges”), (ii) tailing storage facility of underground iron mines, (iii) waste rock dumps of the Iron Ore Mining and Dressing Plant, (iv) waste rock dumps of the Granite Quarry Plant. It was established that on the devastated lands in Kryvyi Rih District, the initial soil formation occurs in very difficult conditions. Therefore, over 25- 100 years only very primitive soils were formed. The following features are inherent to them: (1) primitive soil profile (thickness 10-100 mm), (2) low levels of soil organic substance content (9.5-11.5 %), (3) alkaline indicators of the soil solution (pHH2O – 8.08-8.92, pHKCl – 7.42-8.23), (4) low levels of cation exchange capacity (6.34-8.47 mMol /100 g). By results of correlation calculations, among the factors of soil formation time (duration of soil formation) and input of plant ash elements’ fall are characterized by the maximum number of statistically significant correlation coefficients and their numerical values. In terms of chemical composition of the technosol, the values of organic matter content and exchangeable acidity (pHKCl) were the most predictable soil formation factors. Generally physical / chemical characteristics of geological rocks (as parent material) and time were the two most important factors in determining the initial pedogenesis on devastated lands in the Kryvyi Rih Iron Mining & Metallurgical District (Ukraine).
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Zhang, Renduo, und David Russo. Scale-dependency and spatial variability of soil hydraulic properties. United States Department of Agriculture, November 2004. http://dx.doi.org/10.32747/2004.7587220.bard.

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Water resources assessment and protection requires quantitative descriptions of field-scale water flow and contaminant transport through the subsurface, which, in turn, require reliable information about soil hydraulic properties. However, much is still unknown concerning hydraulic properties and flow behavior in heterogeneous soils. Especially, relationships of hydraulic properties changing with measured scales are poorly understood. Soil hydraulic properties are usually measured at a small scale and used for quantifying flow and transport in large scales, which causes misleading results. Therefore, determination of scale-dependent and spatial variability of soil hydraulic properties provides the essential information for quantifying water flow and chemical transport through the subsurface, which are the key processes for detection of potential agricultural/industrial contaminants, reduction of agricultural chemical movement, improvement of soil and water quality, and increase of agricultural productivity. The original research objectives of this project were: 1. to measure soil hydraulic properties at different locations and different scales at large fields; 2. to develop scale-dependent relationships of soil hydraulic properties; and 3. to determine spatial variability and heterogeneity of soil hydraulic properties as a function of measurement scales. The US investigators conducted field and lab experiments to measure soil hydraulic properties at different locations and different scales. Based on the field and lab experiments, a well-structured database of soil physical and hydraulic properties was developed. The database was used to study scale-dependency, spatial variability, and heterogeneity of soil hydraulic properties. An improved method was developed for calculating hydraulic properties based on infiltration data from the disc infiltrometer. Compared with the other methods, the proposed method provided more accurate and stable estimations of the hydraulic conductivity and macroscopic capillary length, using infiltration data collected atshort experiment periods. We also developed scale-dependent relationships of soil hydraulic properties using the fractal and geostatistical characterization. The research effort of the Israeli research team concentrates on tasks along the second objective. The main accomplishment of this effort is that we succeed to derive first-order, upscaled (block effective) conductivity tensor, K'ᵢⱼ, and time-dependent dispersion tensor, D'ᵢⱼ, i,j=1,2,3, for steady-state flow in three-dimensional, partially saturated, heterogeneous formations, for length-scales comparable with those of the formation heterogeneity. Numerical simulations designed to test the applicability of the upscaling methodology to more general situations involving complex, transient flow regimes originating from periodic rain/irrigation events and water uptake by plant roots suggested that even in this complicated case, the upscaling methodology essentially compensated for the loss of sub-grid-scale variations of the velocity field caused by coarse discretization of the flow domain. These results have significant implications with respect to the development of field-scale solute transport models capable of simulating complex real-world scenarios in the subsurface, and, in turn, are essential for the assessment of the threat posed by contamination from agricultural and/or industrial sources.
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