Retention and release of diquat and paraquat herbicides in soils

Soil Research ◽  
1993 ◽  
Vol 31 (1) ◽  
pp. 97 ◽  
Author(s):  
RS Kookana ◽  
LAG Aylmore
Keyword(s):  
Clay Soil ◽  
Chemical Properties ◽  
Sorption Isotherms ◽  
Clay Content ◽  
Langmuir Coefficient ◽  
Physical And Chemical ◽  
Western Australian ◽  
Very High ◽  
Different Soils ◽  
And Chemical Properties

The sorption and desorption behaviour of diquat and paraquat, in the presence of different salt concentrations, has been studied in some Western Australian soils varying in physical and chemical properties. Sorption isotherms were found to be of the 'L' type according to the Giles classification with the data fitting well to the Langmuir equation. The sorption capacities of soils for diquat ranged from very high in clay soil (146 400 �mol kg-1) to very low in sand (1765 �mol kg-1) and followed the order of clay content in the soils. The clay soil also showed the highest value for the Langmuir coefficient representing bonding energy. The sorption capacities for the herbicides were less than the CEC of the soils. Both the type and content of clay minerals present in soil were important for sorption and subsequent desorption of the dipyridylium herbicides. An increase in the salt concentration of the soil solution (from 0.005 to 0.05 M CaCl2) resulted in decreases in sorption capacities for the herbicides ranging from some 17% to 40% in the different soils. Both Ca2+ and Na+ cations competed for the sorption sites with the herbicides, but Na+ was not as effective as Ca2+. Desorption of the herbicides was also significantly affected by the salt concentrations of the extractant. After five successive extractions with 0.005 m CaCl2, the total amounts of equilibrium sorption desorbed from the Bassendean surface soil were 13% and 7% for diquat and paraquat, respectively. The percentages of diquat removed by extractions decreased with increasing clay contents in the soils studied. Desorption of diquat was higher than that of paraquat at all salt concentrations. Hysteresis was evident between sorption and desorption isotherms.. As sorption increased, the desorption became easier, indicating that the herbicides were less strongly held. Sorption which occurred in the presence of higher ionic strength solutions of inorganic cations was relatively less susceptible to desorption.

scholarly journals Interferons: Purification and Physicochemical Aspects

1970 ◽  
Vol 56 (1) ◽  
pp. 113-133 ◽  
Author(s):  
K. H. Fantes
Keyword(s):  
Chemical Properties ◽  
Pure Substance ◽  
Physical And Chemical Properties ◽  
High Purification ◽  
Interferon Activity ◽  
Physical And Chemical ◽  
Very High ◽  
And Chemical Properties

Antiviral interferon activity in any one species can be exhibited by a variety of substances that differ in their physical and chemical properties, but the nature of these differences is not understood. Conditions that can lead to the formation of diverse types of interferons have been outlined. Reasons have been adduced why, for certain purposes, purification of interferons is desirable or even necessary, and examples have been presented to show how and to what extent this has been achieved. In spite of some very high purification factors, not a single interferon has been obtained as a pure substance. Therefore, all available knowledge of physical and chemical properties has been obtained by indirect means.

Extremely high diversity of euglenophytes in a small pond in eastern Poland

2018 ◽  
Vol 151 (1) ◽  
pp. 18-34 ◽  
Author(s):  
Małgorzata Poniewozik ◽  
Josef Juráň
Keyword(s):  
Chemical Properties ◽  
Diversity Indices ◽  
Common Species ◽  
Temperature Conductivity ◽  
Upgma Cluster Analysis ◽  
Water Ph ◽  
Special Concern ◽  
Physical And Chemical ◽  
Very High ◽  
And Chemical Properties

Background and aims – Phytoplankton samples were taken from a periodic, small and very shallow former clay-pit pond in eastern Poland near Lublin city. Diversity of the euglenophyte community was assessed during the period 2002–2004 and in 2014. Methods – Water samples were collected with a 20 µm plankton net and with a slime aspirator (20 ml capacity) from the surface of the bottom. One aliquot of each sample was fixed for SEM observation; the fresh part of the sample was analysed using light microscope. Physical and chemical properties of the water (pH, temperature, conductivity, phosphates and ammonium salt contents) were measured. Diversity indices were calculated (Shannon-Wiener, evenness, Margalef and Simpson) and UPGMA cluster analysis was applied to discern differences among euglenoid assemblages.Key results – In total, 63 euglenophyte taxa were found. The euglenophyte community was dominated by species belonging to the Trachelomonas genus (29 taxa). The most abundant and constant component were widespread and common species such as T. caudata, T. hispida, T. intermedia, T. volvocina and T. volvocinopsis. They usually occurred in very high densities. We also found some rarely reported euglenophytes including Euglena granulata, Trachelomonas lemmermannii, and T. sydneyensis. Conclusions – Euglenophytes were, with a few exceptions, the only group inhabiting the pond. Representatives of other groups such as diatoms or Scenedesmus species were recorded only occasionally. Nearly half of the taxa that were recorded in the first period (2002–2004) were found again after ten years. Of special concern was taxa belonging to the genus Trachelomonas. Trachelomonads, although known to represent taxa preferring waters moderately rich in nutrients, were very numerous in the investigated pond, which was enriched in phosphorus and nitrogen compounds.

scholarly journals PEMANFAATAN PUPUK BOKASIH TERHADAP PENINGKATAN KESUBURAN FISIK DAN KIMIA TANAH PADA LAHAN PEMBUDIDAYAAN TANAMAN TOMAT (Lycopersicum esculentum MILL.)

AGRICA ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 17-21
Author(s):  
Paulus O Lana ◽  
Charly Mutiara
Keyword(s):  
Pore Space ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Tomato Plants ◽  
Total Soil ◽  
Soil Pore Space ◽  
Physical And Chemical ◽  
Very High ◽  
Properties Of Soil ◽  
And Chemical Properties

This study aims to determine the effect of bokashi fertilizer dosage on the physical and chemical properties of soil on tomato plants and the optimum dose of bokashi fertilizer which can provide the best influence on the physical and chemical properties of the soil. The research design used was a randomized block design (RBD) with a single factor pattern consisting of five treatments namely B0 = 0 tons ha-1 bokashi fertilizer (control), B1 = 5 tons ha-1 bokashi fertilizer, B2 = 10 tons ha-1 bokashi fertilizer, B3 = 15 tons ha-1 bokashi fertilizer, B4 = 20 tons ha-1 bokashi fertilizer. The observation variables in this study were soil volume/bulk density (gr /cm3), total soil pore space (%), N- total soil, available P-soil, available K-soil, soil C-organic, and soil pH. The results showed that the administration of bokashi fertilizer was able to improve the physical properties of soil in tomato plants, namely the weight of the soil volume decreased by 1,120 gr / cm³, water holding capacity increased by 30.24%, and soil pore space increased by 57.74%, so that the soil aggregate became good Giving doses of bokashi fertilizer can improve soil chemical properties in tomato plants, namely C-organic 0.91% very low, N-total soil 0.32% medium, P-available 37.25 ppm very high, and K-available 425.64 ppm very high and soil pH to 6.81 neutral. The supply of 20 tons/ha of bokashi fertilizer can improve soil physical and chemical properties optimally in tomato plants.

scholarly journals From the study of the characteristics of the mountain dark kastanozem in the mouth of Shar Khad in Uvur Zaisan, Bogd Khan mountain

2021 ◽  
Vol 31 (3) ◽  
pp. 137-142
Author(s):  
Lkhamsuren Byambaja ◽  
Khishigsaikhan Adiyazar ◽  
Janchivdorj Baatarkhuu ◽  
Soronzongombo Byambaa ◽  
Namjilsuren Ganbaatar
Keyword(s):  
Structural Stability ◽  
Soil Structure ◽  
Humus Content ◽  
Chemical Properties ◽  
Clay Content ◽  
Physical And Chemical Properties ◽  
Control Parameters ◽  
Physical Clay ◽  
Physical And Chemical ◽  
And Chemical Properties

We cut in 25.5 hectares of soil at the mouth of Shar Khad in Uvur Zaisan, Bogd Khan Uul, made morphological records, determined the soil structure, its stability, physical and chemical properties, and compared it with the soil properties of the fenced area selected as the main control parameters. In this study, we compared the structure, structural stability, physical and chemical properties of mountain dark kastanozem. For the soil structure of the study area, the proportion of 0.25-10 mm structure in the 0-8 cm layer is 5-18 %, and the structure size of less than 0.25 mm is 27 %, and the structural stability is 2-2.5 on average at 0-3 cm soil In terms of points and mechanical composition, light loam and sandy soils predominated in the 0-8 cm layer of soil, sand content increased by 48.2%, physical clay content decreased by 68.8%, and humus content decreased by 0.6% from the fenced area selected for control. As a result, the characteristics of the dark kastanozem degraded of the settled area. Богдхан уулын Өвөр Зайсангийн Шар хадны амны уулын хар хүрэн хөрсний шинж чанарыг судалсан дүн Бид Богд Хан уулын Өвөр Зайсангийн Шар хадны амны  25.5 га талбайн хөрсөнд зүсэлт хийж, морфологи бичиглэл үйлдэн, хөрсний бүтэц, түүний тогтвортой байдал, физик, химийн шинж чанарыг тодорхойлон голлох үзүүлэлтээр хяналт болгон сонгож авсан хашиж хамгаалсан талбайн хөрсний шинж чанартай харьцуулан уг судалгааг хийж гүйцэтгэв. Бид уг судалгаагаар уулын хар хүрэн хөрсний бүтэц, бүтцийн тогтвортой байдал, физик, химийн шинж чанарыг харьцуулан судлав. Судалгааны талбайн хөрсний бүтцийн хувьд 0-8 см үе давхаргад 0.25-10 мм хэмжээтэй бүтцийн эзлэх хувь 5-18 %, 0.25 мм-ээс бага хэмжээтэй бүтэц 27 %-ийг эзэлж, бүтцийн тогтвортой байдал хөрсний 0-3 см үед дунджаар 2-2.5 балл, механик бүрэлдэхүүний хувьд хөрсний 0-8 см үе давхаргад хөнгөн шавранцар механик бүрэлдэхүүн зонхилж, элсний агууламж 48.2 %-иар нэмэгдэж, физик шаврын агууламж 68.8 %-иар, ялзмагийн агууламж хяналт болгон сонгож авсан хашсан талбайнхаас 0.6 %-иар тус тус буурсан байна. Мөн хөрсний шим тэжээлийн элементүүд болох хөдөлгөөнт фосфор, солилцох калийн агууламжийн хувьд ч хашсан талбайнхаас бага байна. Дээрхи үр дүнгээс үзэхэд судалгааны талбайд тогтворжсон уулын хар хүрэн хөрсний шинж чанарт мэдэгдэхүйц өөрчлөлт орж талхагдал, доройтолд өртжээ гэж үзэх үндэстэй байна.  Түлхүүр үг: Хөрсний бүтэц, хөрсний бүтцийн тогтвортой байдал, хөрсний физик шинж, хими шинж, хөрсний доройтол

Pronamide Phytotoxicity in Ten Wisconsin Soils

Weed Science ◽  
1980 ◽  
Vol 28 (4) ◽  
pp. 429-432 ◽  
Author(s):  
T. E. Dutt ◽  
R. G. Harvey
Keyword(s):  
Organic Matter ◽  
Chemical Properties ◽  
Clay Content ◽  
Exchange Capacity ◽  
Fresh Weight ◽  
Relationship Of ◽  
Physical And Chemical ◽  
Mg Content ◽  
The Relationship ◽  
And Chemical Properties

Pronamide [3,5-dichloro-(N-1, 1-dimethyl-2-propynyl) benzamide] phytotoxicity was compared in 10 Wisconsin soils and the relationship of activity to soil physical and chemical properties appraised. Twelve soil properties were measured and correlated with pronamide I50(50% fresh weight inhibition) values using oats (Avena sativaL. ‘Portal’) as the indicator plant in bioassays conducted under greenhouse conditions. Organic matter was the soil variable most inversely correlated with pronamide phytotoxicity. Cation exchange capacity, field moisture capacity, and Mg content were also inversely correlated with pronamide phytotoxicity, but probably reflect changes in soil organic matter levels. Clay content did not significantly affect pronamide phytotoxicity.

scholarly journals Characterization and classification of soils of Northern hills Zone of Chhattisgarh, Madhya Pradesh

2021 ◽  
Vol 17 (AAEBSSD) ◽  
pp. 147-149
Author(s):  
P.N. Tripathi ◽  
U.S. Mishra ◽  
Pawan Sirothia ◽  
R.P. Singh
Keyword(s):  
Cation Exchange Capacity ◽  
Chemical Properties ◽  
Clay Content ◽  
Exchange Capacity ◽  
Organic Carbon Content ◽  
Physical And Chemical Properties ◽  
Clay Loam ◽  
Physical And Chemical ◽  
And Chemical Properties

Three representative soil pedonsof northern hills of Chhattisgarh, M.P were morphologically studied, characterized and classified. The soils are very deep, colour ranges from brown (10YR5/3) to dark brown (10YR3/3) and very dark greyish brown (10YR3/2) in different horizons. Fe and calcretes are observed in sub surface horizons. The texture in surface soils varied from clay loam to clay while in pedon 2, the texture was observed sandy clay loam throughout the profile. The soils are calcareous and pH ranged from 7.0 to 7.5. The organic carbon content in these soils were (4.4 g kg-1), low to medium (6.1 g kg-1) in surface and decreased with depth. Cation exchange capacity (CEC) were found high in horizons where clay content was more. Based on morphological, physical and chemical properties P1 and P3 were classified as VerticHaplustalfs and pedon (P2) was placed under Typic Haplustepts.

scholarly journals Characterization of Southwestern Nigeria River Sand for foundry use

2020 ◽  
Vol 13 (2) ◽  
Author(s):  
B.V. Omidiji ◽  
H.A. Owolabi ◽  
D.A. Adetan
Keyword(s):  
Chemical Properties ◽  
Clay Content ◽  
Gray Iron ◽  
River Sand ◽  
Southwestern Nigeria ◽  
Ferrous Metals ◽  
Physical And Chemical ◽  
Moulding Material ◽  
And Chemical Properties

The greater number of castings produced globally are made by using sand casting techniques that utilize sand as major moulding material. This paper characterizes Isasa River sand based on its physical and chemical properties with the aid of Tandem pelletron electrostatic accelerator, trinocular microscope, mechanical sieve shaker, and box furnace, for Foundry application. Results obtained revealed that the River sand has moisture content of 4.30%, clay content of 2.22%, grain fineness number (GFN) of 49, Silica (SiO2) content of 93%, and sintering point of 1400oC. The River sand is a 4-screen sand, having angular grains with medium sphericity. Isasa River sand will be suitable for casting of gray iron and non-ferrous metals, with the addition of binding agent in suitable proportion.

scholarly journals STRONTIUM CONTENT IN SANDY SOILS IN AGRICULTURE FIELDS (CASE STUDY: MOUNDOU, CHAD)

AGROFOR ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Kamssou KOI ◽  
Victor NAGORNY ◽  
Otilija MISECKAITE ◽  
Yuri MAZHAYSKY
Keyword(s):  
Soil Depth ◽  
Chemical Properties ◽  
Sandy Soils ◽  
Total Content ◽  
Exchange Capacity ◽  
Strontium Content ◽  
Physical And Chemical ◽  
Very High ◽  
And Chemical Properties

During evaluation of physical and chemical properties of sandy soils and theirfertility in Southern part of Republic of Chad it has been revealed that some soilshave very high content of strontium. Its content varies from 10 to 270 mg/kg ofsoil depending on type of soil, depth of soil layers, clay and organic content.Strontium content negatively correlates with total content of calcium andphosphorus in layers of soil. Low CEC (CEC - Cation-exchange capacity) of soilmay be a reason of possible translocation of strontium from higher to lower layersof soils. Strontium content in soils do not relates with level of radioactivity of soilmeasured. The highest content of strontium has been found in soils developed onsome eolian and colluvio-alluvium deposits. Some researchers hypothesize thatsome endemic and chronic diseases such as Kashin-Beck disease, `Dysostosisenchondralis endemic`, endemic hoiter, osteoarthritis might be caused by highcontent of strontium in water and plant foods contaminated with it. Absence ofconsensus on etiological factors of these diseases confirms that it is worthconsidering necessity of further studies of different affects of high content ofstrontium in water and foods on human health directly or indirectly throughcausing misbalance in mineral nutrition.

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