scholarly journals (160) Are All Vermicomposts Created Equal?

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1006A-1006
Author(s):  
Gray R. Bachman

The horticulture industry continues to show interest in using stabilized organic wastes as a component of container media. Vermicompost, also known as worm-worked waste or worm castings, is one of these materials of interest and can be produced from a number of organic wastes, including manure wastes. One issue that has not been addressed is the uniformity of vermicomposts produced from wastes of different sources. Are all vermicomposts created equal? The uniformity of vermicompost is important for growers to consider when using as a medium amendment. This research project investigated the physical properties of vermicompost 1) from different sources of wastes and 2) from a single waste source sequentially sampled over time. The first stage determined the physical properties of vermicompost from beef manure, hog manure, and peat-based media used by two earthworm growers. There were significant differences between the four vermicomposts in bulk density, air volume, percent air volume, percent volumetric moisture, total porosity, and water holding capacity. The second stage involved determining the physical characteristics of vermicompost produced from beef manure collected at the Illinois State University Research Farm from cattle receiving a consistent diet through the year. Manure was collected bimonthly. There was no difference in vermicompost bulk density among the samples. There were significant differences in air volume, percent air volume, percent volumetric moisture, total porosity, and water holding capacity. These changes in vermicompost physical characteristics must be quantified for growers to accurately predict performance as a growth medium amendment.

2015 ◽  
Vol 7 (1) ◽  
pp. 129-135 ◽  
Author(s):  
Abd El-Moneim M. R. AFIFY ◽  
Hossam Saad EL-BELTAGI ◽  
Samiha M. ABD EL-SALAM ◽  
Azza A. OMRAN

Three white sorghum varieties (named ‘Dorado’,‘Shandaweel-6’ and ‘Giza-15’) were investigated for grain characteristics and processed whole meal flour (via soaking, cooked, germinated and fermented sorghum). ‘Giza-15’ variety was the highest one in 1,000 kernel weight and hectolitre, followed by ‘Dorado’ and ‘Shandaweel-6’ that were significant lower. Sorghum varieties were non-significant different in L scales. ‘Giza-15’ was the highest variety in a and b scales. Sorghum varieties were significant different in c scales and non-significant different in h scales. Shandaweel-6 recorded the highest value in water holding capacity (WHC).‘Giza-15’recorded the highest variety in oil holding capacity (OHC). The most significant increase in WHO was after fermentation treatment, followed by cooking treatment. Regarding OHC, the most significant increase was after germination treatment. Biscuits prepared from 50% whole meal flour of raw, soaked, cooked, germinated and fermented sorghum were evaluated for sensory and physical characteristics. The sensory results showed that 50% sorghum whole meal flour could be incorporated to prepare acceptable quality biscuits. The diameter of sorghum biscuits increased, while the diameter of wheat biscuits decreased. Hardness of sorghum biscuits was significant decreased in all treatments compared with wheat biscuits. Hardness of germinated sorghum biscuits was close to wheat biscuits values.


2019 ◽  
pp. 115-129
Author(s):  
Jorge Cabelin ◽  
Beatriz Jadina

Landslides have become very frequent in Leyte which justifies the need for soil assessment and characterization of the landslide-prone areas in the province. This study assessed the physical characteristics of soils from the landslide areas in Cadac-an watershed in Leyte, Philippines. Landslide cuts located in the central highlands of Cadac-an watershed were used as representative profiles in this study. These were examined, characterized and sampled for the analyses of soil physical properties which include particle size distribution (Pipette method), bulk density (Paraffin-clod method), particle density (Pycnometer method), porosity, total soil wet density, water holding capacity and field capacity (Gravimetric method), saturated hydraulic conductivity (Constant head method), liquid limit and plastic index. Generally, soils from the landslide areas in Cadac-an watershed had a sandy loam to clay loam to clayey texture, low bulk density, low particle density, high porosity, moderate total soil wet density, moderate to high water holding capacity, low to moderate field capacity, moderately high to high saturated hydraulic conductivity, moderate liquid limit and low plastic index. Based on the above characteristics, the soils are susceptible to landslide occurrence thus it is highly recommended to conduct constant assessment and monitoring the area.


HortScience ◽  
1991 ◽  
Vol 26 (6) ◽  
pp. 741G-741
Author(s):  
M.T. Kelley ◽  
G.C. Elliott ◽  
R.J. McAvoy

Four different granulated rockwool (RW) aggregates were combined with peat at 15, 30, or 45 percent (v/v) RW resulting in twelve different peat:RW media. The RW aggregates used were either fine or coarse textured and absorbent or repellent to water. A soil based medium was used as a control. Bulk volume, bulk density, total porosity, water porosity (WP), and aeration porosity (AP) were determined for all media. Hybrid lily, cvs. `Enchantment' and `Jamboree', growth in these media were compared by measuring the dates of visible bud and anthesis, flower number, leaf number and area, plant height and dry weight of stems, leaves, and flowers. Physical properties of the RW media varied significantly from the soil based medium. Increasing the volume percent RW had a negative linear effect on WP but a positive linear effect on AP for all RW aggregates. Lily growth in the soil based medium was statistically similar to all RW media. The dates of visible bud and anthesis, as well as leaf number and area decreased linearly as the volume percent repellent coarse RW increased.


Khazanah ◽  
2020 ◽  
Vol 12 (2) ◽  
Author(s):  
Warit Abi Nurazaq ◽  
◽  
Bambang Purwantana ◽  
Radi Radi ◽  
Andri Prima Nugroho ◽  
...  

Tropical country has a large biomass provide from agricultural residue. The biomass has potential to be processed as biochar. In general, biochar can be utilized as soil amendment in order to increase the ability of soil to retain nutrients, reduce surface runoff, due to excess water, and adding biodiversity of soils that are very useful for plant growth. The biochar characteristics are strongly related to the feedstock types and also their pyrolysis method. This research aims to study the physical characteristics of tropical biochar and their potential suitability in soil improvement. The biochar was produced by slow pyrolysis method using a vertical bed kiln. The feedstock were 9 types of agricultural residue including: mango leaf, longan leaf, teak leaf, mango branch, longan branch, rubber branch, corncob, rice straw, and rice husk. Temperature of the pyrolisis process was in the range of 400 °C to 600 °C. The results indicated that the physical properties of feedstock affects the characteristics of biochar. The higher bulk density and fixed carbon value the greater yield of biochar. Compare to their raw materials, the average water content of biochar was reduced (0.2–3.85 %), while pH increased (7.06–9.9). The electrical conductivity in general also increased (0.11–2.9 ds.m-1 ). Bulk density changed, corncob, and branches materials decreased, while rice straw, rice husk and leaves materials increased. The water holding capacity was a fairly low number (4–20 %). Application of the utilized biochar as a soil amendment is to improve soil chemical properties (pH, electrical conductivity, and availability of N-P contents) and physical properties (bulk density, porosity, and water holding capacity). Application for different soil types requires different biochar characteristics, it is influenced by the type of raw material used, temperature, and combustion time.


2007 ◽  
Vol 17 (3) ◽  
pp. 301-304 ◽  
Author(s):  
Michael R. Evans ◽  
Leisha Vance

A series of soilless root substrates was formulated to contain either 20% composted pine bark or perlite and 0%, 10%, 20%, or 30% feather fiber, with the remainder being sphagnum peat. The substrates containing bark or perlite with 0% feather fiber served as the controls for the bark- and perlite-containing substrates respectively. For root substrates containing perlite, the inclusion of feather fiber increased the total pore space compared with the control substrate. For substrates containing bark, the inclusion of 10% or 20% feather fiber increased total pore space, but the inclusion of 30% feather fiber reduced total pore space. For substrates containing perlite, the inclusion of feather fiber increased the air-filled pore space compared with the control, and as the percentage feather fiber increased, air-filled pore space increased. For substrates containing bark, the inclusion of 10% or 20% feather fiber increased air-filled pore space, but air-filled pore space of the substrate containing 30% feather fiber was not different from the control. For all substrates, the inclusion of feather fiber reduced the water-holding capacity, but water-holding capacities for all substrates remained within recommended ranges. The bulk density of feather fiber-containing substrates was not different from the control except for the substrate containing 30% feather fiber with bark, which had a higher bulk density than its control without feather fiber. The difference in physical properties of the 30% feather fiber substrate with bark from its control substrate was attributed to the aggregation of the feather fiber when formulated with composted bark. Aggregation of feather fiber when blended into substrates at levels of 30% or higher would create difficulties in achieving uniform substrates.


2008 ◽  
Vol 8 (1) ◽  
pp. 16-20 ◽  
Author(s):  
Burhanudin Sundu

ABSTRACT. The world’s copra meal production amounted to 1.8 million tonnes in 2002 and most of it was produced in Asia. The Philippines and Indonesia contributed approximately 65% of the world’s copra meal production. The main problems of using copra meal in poultry diets are its physical properties along with its nutritional profiles. This study was conducted to determine the physical characteristics and feeding value of copra meal. Physical characteristics were determined by measuring the bulk density and water holding capacity of copra meal and a digestibility study was undertaken to investigate nutrient digestibility, jejunal digesta viscosity and apparent metabolizable energy of copra meal. A total of 28 day old male Ross chicks were given control starter and grower diets from day 1 to 35. From day 36 to 42 , the birds were fed an experimental diet. Faeces were collected for three consecutive days. Jejunal digesta was measured for viscosity and ileal digesta was used for amino acid digestibility measurements.Data indicated that bulk density and water holding capacity of copra meal were poor, being 0.49 g/cm3 and 4.69 g water / g feed respectively. Although the crude proteind and amino acids contents of copra meal were favourable to meet a broiler chicken’s requirements, their digestibilities were low and lysine digestibility being the lowest while arginine digestibility was high. Dry matter, neutral detergent fibre digestibility and apparent metabolizable energy were also low. The low digestibilities of nutrients were not due to the jejunal digesta viscosity as jejunal digesta viscosity was low.


HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 979B-979
Author(s):  
Johann S. Buck ◽  
Michael R. Evans ◽  
Paolo Sambo

Horticultural root substrates are designed to provide the optimal physical properties for plant growth. These properties include bulk density (g·cm-3), air-filled pore space (% v/v), total pore space (% v/v), water-filled pore space (% v/v), water-holding capacity (% v/v and w/w), and wettability. Whole, fresh parboiled rice hulls were ground to produce four grades with varying particle size distributions. Particle sizes for the four grades ranged from <0.25 to >2.80 mm. Additionally, discrete particle sizes of <0.25, 0.50, 1.00, 2.00, 2.80, and >2.80 mm were produced. For all grade distributions and particle point sizes, physical properties were determined and contrasted against Canadian sphagnum peat. As the proportion of smaller particle sizes in the distributions increased or as the particle point sizes decreased, total pore space (% v/v) and air-filled pore space (% v/v) decreased, while, bulk density (g·cm-3) and water-holding capacity (% v/v and w/w) increased. Additionally, as the proportion of particle sizes from <0.25–0.50 mm increased, the wettabilty of the whole fresh parboiled rice hull material decreased. Particle sizes ranging from 1.00–2.80 mm possessed the physical properties most suitable for plant growth in containerized greenhouse crop production and were most similar to peat.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 492c-492
Author(s):  
Chris Ely ◽  
Mark A. Hubbard

Azomite is a mined, commercially available, hydrated sodium calcium aluminosiliclate soil amendment reported to act as a source of mineral elements. To determine its effect on plant growth, Dendranthema `Connie' rooted cuttings, Malus seedlings, and Citrus seedlings were grown in containers in one of two growing media: ProMix BX or ProMix BX with Azomite (1:1, v:v). Plant height was monitored weekly and after 6 weeks of growth, fresh and dry plant weights of roots and shoots were determined. There was no difference in any of the parameters measured as a result of the addition of Azomite. Any nutritional influence of the Azomite may only be evident in different conditions, e.g., field soil, or over an extended period of time. The Azomite altered the medium's physical properties and therefore bulk density and water-holding capacity of the Azomite were determined for consideration.


Author(s):  
Kelsey Watts

Soils play a critical role to society as a medium that facilitates crop production and also contributes to the energy and carbon balance of the Earth System. Land-use change and improper land-use is one of the dominant factors affecting soil erosion and nutrient loss in soils. We examined the effects of land-use change on an Elmbrook clay/clay-loam soil on a farm in Ameliasburg on the northern part of Prince Edward County. Three cover types were examined: a sod field (established for over 10 years), a wheat field (part of a wheat/corn/soybean rotation for 30 years) and an undisturbed deciduous forest. Under each land-use type, cores to a depth of 40 cm were collected along three random 30 m transects (at 8, 16 and 24 m), then divided them into 10 cm increments, combining all similar depth increments along one transect. Soil quality was assessed by analyzing various soil physical and chemical properties. Bulk density of the soil was much higher (1.55 vs. 0.95 g/cm3) in both agricultural ecosystems compared to the forest, but only in the 0-10 cm layer. Soil moisture at 60% water holding capacity was much greater for the forest than the sod and wheat soils. Soil pH was slightly lower in the forest compared to the sod and wheat fields. The sod and wheat fields showed losses of ~52% and ~53% organic matter, respectively, in contrast to the forested area. The greatest differences in organic matter and total carbon were found in the top 10 cm, likely due to the greater accumulation of litter at the ground surface in the forest compared to the agricultural sites. It appears that long-term (10 year) agricultural production has led to a decline in some, but not all, soil quality measures, particularly soil organic matter, bulk density and water holding capacity. These findings are consistent with much of the literature concerning the effects of land-use change on soil quality, and highlight the need to develop improved management systems to minimize losses in soil quality that can lead to declines in the productivity potential of soils over time.


Soil Research ◽  
2017 ◽  
Vol 55 (8) ◽  
pp. 778
Author(s):  
G. S. A. Castro ◽  
C. A. C. Crusciol ◽  
C. A. Rosolem ◽  
J. C. Calonego ◽  
K. R. Brye

This work aimed to evaluate the effects of crop rotations and soil acidity amelioration on soil physical properties of an Oxisol (Rhodic Ferralsol or Red Ferrosol in the Australian Soil Classification) from October 2006 to September 2011 in Botucatu, SP, Brazil. Treatments consisted of four soybean (Glycine max)–maize (Zea mays)–rice (Oryza sativa) rotations that differed in their off-season crop, either a signal grass (Urochloa ruziziensis) forage crop, a second crop, a cover crop, or fallow. Two acid-neutralising materials, dolomitic lime (effective calcium carbonate equivalent (ECCE) = 90%) and calcium-magnesium silicate (ECCE = 80%), were surface applied to raise the soil’s base saturation to 70%. Selected soil physical characteristics were evaluated at three depths (0–0.1, 0.1–0.2, and 0.2–0.4 m). In the top 0.1 m, soil bulk density was lowest (P < 0.05) and macroporosity and aggregate stability index were greatest (P < 0.05) in the forage crop compared with all other production systems. Also, bulk density was lower (P < 0.05) and macroporosity was greater (P < 0.05) in the acid-neutralising-amended than the unamended control soil. In the 0.1–0.2-m interval, mean weight diameter and mean geometric diameter were greater (P < 0.05) in the forage crop compared with all other production systems. All soil properties evaluated in this study in the 0.2–0.4-m interval were unaffected by production system or soil amendment after five complete cropping cycles. Results of this study demonstrated that certain soil physical properties can be improved in a no-tillage soybean–maize–rice rotation using a forage crop in the off-season and with the addition of acid-neutralising soil amendments. Any soil and crop management practices that improve soil physical properties will likely contribute to sustaining long-term soil and crop productivity in areas with highly weathered, organic matter-depleted, acidic Oxisols.


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