NATURE OF HYDR0PHILIC POLYMERS AND THEIR EFFECT ON SOIL PROPERTIES

The levels of hydration of several hydrophilic polymers (hydrogels) varied greatly. Starch-based polymers had the fastest rate of hydration (<2 hours), followed by a propenoate-propenamide copolymer. Polyacrylamide materials required 4 to 8 hours to become fully hydrated. Maximum water retention in distilled water varied from 400 to 57 g of water per gram of dry material. All hydrogels retained less water in the presence of metal ions or fertilizers in the soaking solution, with substances releasing Fe+2 being the most detrimental. After exposure to fertilizers and ions, the water-holding capacity of a polyacrylamide with a high degree of cross linkage, but not that of hydrogels of the other structures, was fully recovered by subsequently soaking in distilled water. Pots amended with a polyacrylamide polymer but without Micromax (a micronutrient source) reached maximum water retention after six irrigations, while those with Micromax required 10 irrigations to reach peak water retention. The amounts of water being held in pots decreased after repeated fertilization. Medium volume increased with increasing levels of the polyacrylamide Supersorb C (0, 2, 4, or 6 g/pot). Micromax incorporated in medium amended with Supersorb C caused a depression in volume. Medium bulk density, total water retention, and water retention per unit volume of medium were increased by the incorporation of the hydrogel, regardless of the presence of Micromax. Noncapillary porosity measured at container capacity in medium amended with Micromax progressively decreased as the amount of hydrogel increased, but remained unchanged in medium without Micromax. Repeated drying and dehydration of the medium resulted in reduced water retention and increased noncapillary pore space.

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Wetting Characteristics of Different Peat and Peat: Bark-based Potting Media: Influence of Wetting Agents in Improving Wetting and Rewetting Performance

HortScience ◽

10.21273/hortsci.31.4.583f ◽

1996 ◽

Vol 31 (4) ◽

pp. 583f-584

Author(s):

Santakumari Mane ◽

James A. Turner

Keyword(s):

Water Retention ◽

Unit Volume ◽

Initial Moisture Content ◽

Wetting Agent ◽

Media Composition ◽

Potting Media ◽

The Media ◽

Wetting Agents ◽

Reduced Water ◽

Agent Treatment

Eight different peat-based or peat: bark-based potting media were evaluated for their wetting performance when treated with the media wetting agent AquaGro 2000 (2–5 oz/yd3). Upon initial irrigation, no differences in wetting uniformity were observed in seven of the eight test media regardless of their media wetting agent treatments. In four media, water retention was reduced by media wetting agent treatment, however, uniform distribution of water was achieved. AquaGro 2000 improved uniformity of initial wetting in one medium in which the initial moisture content was 6.5%. Uniformity of wetting and water retention improved with increasing wetting agent rate. All media were allowed to air dry and then were re-irrigated. Wetting agent-treated media rewet uniformly, while rewetting varied greatly in untreated media (7.5%–82.5%). Less than 50% of the mass of untreated media wet subsequent to drying. Those portions of the untreated media that did wet retained up to three times more water per unit volume compared to AquaGro 2000-treated media. AquaGro 2000 enhanced uniformity of rewetting, reduced water logging, and improved drainage at all rates (2–5 oz/yd3) tested. Media composition (peat vs. peat: bark did not affect wetting agent efficacy.

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Comparing Potting Media Available to Consumers through Garden Centers and National Chain Stores

HortScience ◽

10.21273/hortsci.31.4.658d ◽

1996 ◽

Vol 31 (4) ◽

pp. 658d-658

Author(s):

Larry J. Kuhns ◽

Tracey L. Harpster

Keyword(s):

Bulk Density ◽

Pore Space ◽

Total Porosity ◽

Tagetes Patula ◽

Soluble Salts ◽

Chain Stores ◽

Nitrate N ◽

Potting Media ◽

The Media ◽

Water Holding

A study was initiated to determine how well plants would grow in potting media available to consumers through garden centers and national chain stores. Nine media were evaluated. The chemical and physical characteristics were determined, and six geraniums (Pelargonium sp) and six marigolds (Tagetes patula) were grown in each of the media. Three of each six were fertilized, three were not. The plants that were fertilized received 100 ppm N and K and 50 ppm P once a week. Three months after seeding the flowers, flowers and buds on the marigolds were counted and the plants were harvested. Dry weights were determined. Nitrate-N ranged from 6 to 627 ppm, pH from 4.9 to 7.1, phosphorus from 88 to 502 pounds/A, potassium from 1.0 to 6.9 meq/100 g, magnesium from 1.4 to 10.8 meq/100 g, calcium from 5.2 to 30.0 meq/100 g, soluble salts from 20 to 151 mmhos, and CEC from 13.0 to 43.8 meq/100cc. Bulk density ranged from 21 to 53 g/100cc, water holding capacity from 32 to 53 ml/100cc, percent air-pore space from 2.7 to 15.7, and total porosity ranged from 65% to 78%. Unfertilized marigolds weighed between 0.1 and 9.6 g; fertilized marigolds weighed 1.4 to 17.2 g. Unfertilized geraniums weighed between 1.4 and 23.3 g; fertilized geraniums weighed 4.4 to 56 g. There were 1.3 to 16 flowers on unfertilized and 7 to 24.3 flowers on fertilized marigolds.

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KENAF PITH AS A VERMICULITE SUBSTITUTE IN PEAT-BASED MEDIA.

HortScience ◽

10.21273/hortsci.27.6.647g ◽

1992 ◽

Vol 27 (6) ◽

pp. 647g-647

Author(s):

Brad B. Hawcroft ◽

Steven E. Newman

Keyword(s):

Pore Space ◽

Hibiscus Cannabinus ◽

Peat Moss ◽

Kenaf Fiber ◽

Fiber Core ◽

Sphagnum Peat ◽

Sphagnum Peat Moss ◽

Celosia Argentea ◽

The Media ◽

Water Holding

Kenaf is an alternative fiber crop being evaluated in Mississippi. Kenaf, primarily grown in Asia, can be used in the manufacture of paper, fiber board, acoustical tiles and compost. The bark is the source of the fiber used, leaving the fiber core or pith for use as a paper additive, poultry litter, or is discarded. The objective of this study was to evaluate the potential use of kenaf fiber core as a vermiculite substitute in a sphagnum peat moss-based medium. Plugs of Celosia argentea, Viola × wittrockiana, and Impatiens wallerana were transplanted into 10 cm pots containing 5 different sphagnum peat moss-based media modified with the milled fiber core (pith) of kenaf (Hibiscus cannabinus) and/or vermiculite. The media were as follows: 5 peat: 0 kenaf : 5 vermiculite (v/v/v); 5 peat : 1 kenaf : 4 vermiculite (v/v/v); 5 peat : 2 kenaf : 3 vermiculite (v/v/v); 5 peat : 3 kenaf : 2 vermiculite (v/v/v); 5 peat : 4 kenaf : 1 vermiculite (v/v/v); and 5 peat : 5 kenaf: 0 vermiculite (v/v/v). Water holding capacity, pore space, pH and media shrinkage were monitored throughout the study along with plant growth and plant quality.

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Soils of Thotapalli Major Irrigation Project of North- Coastal Andhra Pradesh: Physical and Chemical Properties

Agropedology ◽

10.47114/j.agroped.2019.j1 ◽

2019 ◽

Vol 29 (1) ◽

Author(s):

K. Himabindu ◽

◽

P. Gurumurthy ◽

P.R.K. Prasad ◽

◽

...

Keyword(s):

Andhra Pradesh ◽

Pore Space ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Clay Loam ◽

Irrigation Project ◽

Maximum Water ◽

Physical And Chemical ◽

Water Holding ◽

And Chemical Properties

Physical and chemical properties of the soils were assessed for the ayacut area of Thotapalli major irrigation project of North-Coastal Andhra Pradesh. Six representative soil pedons were studied in Devarapalli, Gujjangivalasa, Patikivalasa, Gangada, Aamiti and Maddivalasa villages falling in ayacut area of Thotapalli major irrigation project. The soil texture ranged from sandy loam to sandy clay loam in upland pedons while sandy clay loam to clay in pedons under cultivated plains. In general, relatively low bulk density was recorded at surface horizons compared to sub-surface layers. Maximum water holding capacity, pore space and volume expansion increased with soil depth. The soils were acidic to alkaline in reaction, non-saline, low to medium in organic carbon content. The CEC ranged from 6.4 to 32.5 cmol (p+) kg-1. The soil exchange complex was dominated by calcium followed by magnesium, sodium and potassium. The soils were found to be low in nitrogen, low to medium in phosphorus and medium to high in available potassium status. Manganese and copper were sufficient but zinc and iron were deficient in soils. The total silica (SiO2) content of pedons varied from 48.10 to 71.40 per cent. Sesquioxide (R2O3) and the molar ratio of SiO2 / R2O3 ranged from 19.01 to 32.4 per cent and varied from 3.74 to 6.59, respectively in different pedons. The SiO2 / Al2O3 ratio and the SiO2 / Fe2O3 ratio varied from 4.43 to 7.65 and from 13.7 to 47.8, respectively. A significant positive correlation of clay content with cation exchange capacity (CEC), maximum water holding capacity (MWHC) was observed. Sand content was positively correlated with silica and negatively correlated with MWHC and volume expansion. Soil organic carbon had a significant positive correlation with soil pore space, available nitrogen, phosphorous, potassium, zinc, manganese, copper and iron, but a negative correlation with soil bulk density. Soil pH was positively correlated with CaCO3 but negatively correlated with available phosphorous, potassium, zinc, manganese, and copper and iron. Soil CaCO3 content was negatively correlated with available phosphorous, potassium, zinc, manganese, copper and iron of the soil.

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Imbibition of Water by Rockwool-Peat Container Media Amended with Hydrophilic Gel or Wetting Agent

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.117.5.757 ◽

1992 ◽

Vol 117 (5) ◽

pp. 757-761 ◽

Cited By ~ 8

Author(s):

George C. Elliott

Keyword(s):

Water Retention ◽

Rank Order ◽

Sprinkler Irrigation ◽

Wetting Agent ◽

Free Drainage ◽

Potting Media ◽

Hydrophilic Gel ◽

Water Holding ◽

Effective Water ◽

Overhead Sprinkler

Water retention at effective water-holding capacity (EWHC) and container capacity (CCAP) were measured in four rockwool-peat potting media amended with a wetting agent and/or a hydrophilic gel in pots 12 cm tall containing 445 cm3 medium, and irrigated by capillary mat, flood-and-drain, trickle emitter, or overhead sprinkler. Water retention was measured by weighing. Irrigation was continued until EWHC (i.e., net water retention when no weight increase could be obtained by further irrigation) was reached. CCAP (i.e., net water retention following saturation and free drainage) was measured at the end of each experiment. Irrigation method and medium amendments significantly affected EWHC. Rank order of irrigation treatments was sprinkler ≥ trickle > flood and drain ≥ mat. Hydrophilic gel increased both EWHC and CCAP, while the wetting agent increased EWHC but decreased or had no effect on CCAP. Significant interactions of gel and wetting agent were observed in some media. EWHC was less than CCAP, and EWHC was better correlated with CCAP with trickle emitter and overhead sprinkler irrigation than with capillary mat and flood-and-drain irrigation.

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Novel Green Hydrogel Material using Bacterial Cellulose

Oriental Journal Of Chemistry ◽

10.13005/ojc/340404 ◽

2018 ◽

Vol 34 (4) ◽

pp. 1735-1740 ◽

Cited By ~ 3

Author(s):

Amorn Chaiyasat ◽

Sirinard Jearanai ◽

Somporn Moonmangmee ◽

Duangtip Moonmangmee ◽

Lew P Christopher ◽

...

Keyword(s):

Bacterial Cellulose ◽

Water Retention ◽

Acetic Acid Bacteria ◽

Solid Content ◽

Carboxyl Groups ◽

Water Retention Value ◽

Swelling Properties ◽

Macromolecular Network ◽

The Media ◽

Maximum Water

The green bacterial cellulose (BC)-based hydrogel materials have successfully prepared by modification and crosslink BC. BC was derived from acetic acid bacteria isolated and selected from ripe fruits. The production of BC was performed by fermentation in various media. It was found that using liquid potato medium represented the highest thickness of BC film (0.80 cm) with 2 wt% solid content covered the media. To reduce the crystallization of BC, carboxyl group was introduced onto BC chains using a carboxymethylation reaction giving carboxymethyl BC (CMBC) and subsequently crosslinked with divinyl sulfone (DVS). The extent of crosslinking influenced on the swelling properties of the hydrogels. Using large DVS amounts (>30 wt%-of CMBC), dense macromolecular network with less capacity spaces in the hydrogel was formed. The maximum water retention value of green hydrogels containing ~3.0 mmol carboxyl groups/g CMBC reached 27 (g/g).

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Physical Properties of Hawaiian Golf Course Sands

HortTechnology ◽

10.21273/horttech.4.2.150 ◽

1994 ◽

Vol 4 (2) ◽

pp. 150-153 ◽

Cited By ~ 1

Author(s):

Charles L. Murdoch ◽

David L. Hensley

Keyword(s):

Particle Size ◽

Hydraulic Conductivity ◽

Particle Size Distribution ◽

Physical Properties ◽

Water Retention ◽

Pore Space ◽

Laboratory Evaluation ◽

Golf Course ◽

Coral Sand ◽

Capillary Pore

Physical properties (particle size distribution, bulk density, capillary pore space, non-capillary pore space, hydraulic conductivity, and water retention) of three imported silica sands (Perth, Malaysian, and Newcastle), a man-made sand product (Mansand), and coral sand alone and in peatmoss mixtures were determined to evaluate their suitability as golf-green substrates. Based on laboratory evaluation of physical properties, the silica sands amended with peatmoss (15%) were superior to coral sand or crushed basalt (Mansand) amended with 15% peatmoss for use in high-traffic turfgrass areas.

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Soils of Thotapalli Major Irrigation Project of North- Coastal Andhra Pradesh: Physical and Chemical Properties

10.47114/j.agroped.2019.jun1 ◽

2019 ◽

Vol 29 (1) ◽

Author(s):

K. Kirmani ◽

◽

P. Gurumurthy ◽

P.R.K. Prasad ◽

◽

...

Keyword(s):

Andhra Pradesh ◽

Pore Space ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Clay Loam ◽

Irrigation Project ◽

Maximum Water ◽

Physical And Chemical ◽

Water Holding ◽

And Chemical Properties

Physical and chemical properties of the soils were assessed for the ayacut area of Thotapalli major irrigation project of North-Coastal Andhra Pradesh. Six representative soil pedons were studied in Devarapalli, Gujjangivalasa, Patikivalasa, Gangada, Aamiti and Maddivalasa villages falling in ayacut area of Thotapalli major irrigation project. The soil texture ranged from sandy loam to sandy clay loam in upland pedons while sandy clay loam to clay in pedons under cultivated plains. In general, relatively low bulk density was recorded at surface horizons compared to sub-surface layers. Maximum water holding capacity, pore space and volume expansion increased with soil depth. The soils were acidic to alkaline in reaction, non-saline, low to medium in organic carbon content. The CEC ranged from 6.4 to 32.5 cmol (p+) kg-1. The soil exchange complex was dominated by calcium followed by magnesium, sodium and potassium. The soils were found to be low in nitrogen, low to medium in phosphorus and medium to high in available potassium status. Manganese and copper were sufficient but zinc and iron were deficient in soils. The total silica (SiO2) content of pedons varied from 48.10 to 71.40 per cent. Sesquioxide (R2O3) and the molar ratio of SiO2 / R2O3 ranged from 19.01 to 32.4 per cent and varied from 3.74 to 6.59, respectively in different pedons. The SiO2 / Al2O3 ratio and the SiO2 / Fe2O3 ratio varied from 4.43 to 7.65 and from 13.7 to 47.8, respectively. A significant positive correlation of clay content with cation exchange capacity (CEC), maximum water holding capacity (MWHC) was observed. Sand content was positively correlated with silica and negatively correlated with MWHC and volume expansion. Soil organic carbon had a significant positive correlation with soil pore space, available nitrogen, phosphorous, potassium, zinc, manganese, copper and iron, but a negative correlation with soil bulk density. Soil pH was positively correlated with CaCO3 but negatively correlated with available phosphorous, potassium, zinc, manganese, and copper and iron. Soil CaCO3 content was negatively correlated with available phosphorous, potassium, zinc, manganese and copper and iron of the soil.

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RICE HULLS AS A SOILLESS MEDIA COMPONENT FOR GREENHOUSE-GROWN PLANTS

HortScience ◽

10.21273/hortsci.29.7.736c ◽

1994 ◽

Vol 29 (7) ◽

pp. 736c-736

Author(s):

Shelly D. Dueitt ◽

Steven E. Newman

Keyword(s):

Bulk Density ◽

Water Retention ◽

Pore Space ◽

Chemical Properties ◽

Dry Weight ◽

Peat Moss ◽

Rice Hulls ◽

Media Component ◽

The Media ◽

Rice Milling

Rice hulls, a by-product of rice milling, were used at various rates in greenhouse media. The objective of this study was to determine if rice hulls can replace peat moss. Hulls, aged and fresh, were blended with vermiculite and peat moss from 0 to 50%, by volume replacing peat moss. Physical and chemical properties including bulk density, total pore space, water retention, pH and soluble salt concentrations were determined in the media blends. Marigolds and salvia were transplanted into 13 cm azalea pots containing each media. The bulk density increased with increasing levels of hulls. Total pore space of the media before planting was decreased with increasing levels of aged hulls, but no differences were detected at the termination of the study. Water retention of both fresh and aged hulls at all levels of media were equivalent to the control media. Before planting, the total soluble salts for media containing fresh hulls was greater than with aged hulls. The pH of the media increased with increasing levels of hulls, fresh and aged. The greatest dry weight and plant height was observed when the media contained 10 to 20% aged hulls.

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