Abstract: Compost may improve the soil quality and contribute to C sequestration. The short-term effects of compost application on soil properties of soil cropped with maize are reported here. Soil plots to which mature compost was added (at 50 Mg ha−1 and 85 Mg ha−1) were analyzed for total organic carbon (TOC), nutrients, heavy metals and other soil properties. In addition, maize plants were weighed at the end of the trial and analyzed for carbon (C), nitrogen (N), phosphorus (P) and heavy metals. The results demonstrate that soil amended with compost has an increased TOC content. The increase was proportional to the amount of compost used. At the highest dose used, compost also increased soil N and P content and the pH. Moreover, after compost application, the total heavy metal contents in soils did not increase. There was no difference between the maize yield from compost treated plots and the control plots. However, maize grains were found to be C, N and P enriched due to the increased nutrient status of the a...

Abstract: Swine manures are known to be a source of a variety of human and animal pathogens. Of particular concern are bacteria causing human food-borne illnesses such as Salmonella and Listeria species. The effects of commonly used manure treatments on the persistence of these pathogens have rarely been compared. The objective of this study was to compare the persistence of Listeria monocytogenes and Salmonella typhimurium during the treatment of swine manure by the most commonly used manure management methods: liquid storage, aerated liquid storage, thermophilic composting (55°C) and manure packing (low temperature composting). Swine manure obtained from Ohio State University's Agricultural Technical Institute swine farm was inoculated with L. monocytogenes and S. typhimurium to obtain a final concentration of 106 CFU/g of each organism. To simulate liquid storage, manure was diluted with water and stored aerated and unaerated at 20-25°C. To simulate pack storage and thermophilic composting, the same manure was a...

Abstract: Earthworm digested wastes (vermicompost) are being produced in increasing quantities and there is much interest in developing new markets for these products In this paper, the responses of wheat (Triticum aestivum var Einstein and Xi19) to vermicompost additions and to combinations of vermicompost and inorganic NPK fertilizer in field and glasshouse environments are considered Plant response was determined by measuring a range of ontogenetic parameters (plant growth, chlorophyll content, fertile ears, tiller number and grain yield) The individual treatments involved the addition of 1, 10 and 30 t ha−1 of vermicompost to soil, or the coapplication of 1, 10 and 30 t ha−1 of vermicompost plus NPK fertilizer where the N addition rate was normalized to 150 kg N ha−1 Photosynthetic pigment development, plant growth, and yield were reduced in all treatments in the absence of inorganic fertilizer However, all coapplication treatments resulted in similar yields to NPK fertilizer alone in both field and glass

Abstract: The capability to determine nitrogen availability of composts is necessary to ensure that such materials will provide sufficient fertilization to the growing crop and cause minimal environmental degradation. A greenhouse study using tall fescue as a bioindicator was used to evaluate nitrogen availability of two biosolids composts, two mixed yard waste-poultry manure composts, and one commercially-processed poultry litter. Five inorganic nitrogen (as NH4NO3-N) treatments applied at 0, 22.5, 45, 67.7, and 90 mg N/kg soil were employed to establish an N calibration curve. Yield, fescue biomass total nitrogen (as total Kjeldahl N (TKN)), and soil TKN and KCl extractable NO3−-N and NH4+-N concentrations of the organically amended treatments were compared to the inorganically fertilized treatments to determine amendment N mineralization rates and N fertilizer equivalent values (NFEV). Nitrogen mineralization rates were greatest in the poultry litter (21%) and Panorama yard waste compost (5%) amended pots. The N...

Abstract: The cumulative emissions of volatile organic compounds (VOCs) resulting from natural decay of selected green waste, i.e. grass clippings, woodchips and prunings, and from composting of the same feedstock were studied. The results indicated that terpenes were the only compounds emitted from the feedstock as they underwent natural breakdown as well as during their composting. Even though there was a wide array of compounds emitted, the results suggested that the following six terpenes i.e., α-pinene, β-pinene, 3-carene, camphene, β-myrcene, and D-limonene, were the most significant compounds encompassing 32.7 to 95.3% of the total emissions. The cumulative VOC emissions varied considerably from a batch to another ranging 11.0 to 347.4 mg/kg-dw expressed as α-pinene. The composting of the same materials in different blends resulted in cumulative emissions ranging from 18.1 to 106.6 mg/kg-dw as α-pinene, representing 60 to 92% reduction compared to the biogenic emissions resulting from natural decay.

Abstract: After imposition of fees for disposal of cattle carcasses by the rendering industry, on-farm methods of mortality disposal are being investigated. Three open-air mortality compost windrows were constructed in January (JAN) and February (FEB) of 2004 in the cold, semiarid climate of southern Alberta, Canada. Windrow A included a base of barley straw a minimum of 46 cm thick, a layer of cattle mortalities (n=12) and a layer of stockpiled manure (minimum of 46 cm) covering the mortalities. Windrows B and C also had a bottom layer of barley straw, with windrow B containing 9 mortalities in 2 layers and windrow C containing 12 mortalities in 3 layers. Due to ambient temperatures > 0°C, carcasses (range 236 to 673 kg) were frozen at the time of windrow construction. Type ‘T’ thermocouples were embedded at the base of B and C windrows and temperatures within 120 cm of the surface were measured using a stainless steel dial probe. Windrows were turned 3 times at 3 mo intervals. Samples were collected from initial ...

Abstract: One of the major problems with agricultural soils in the tropical region of the western Pacific islands is their low organic matter content, which results from rapid decomposition due to the hot and humid environment. Composted organic material is frequently applied on agricultural fields as an amendment to provide nutrients and also to increase the organic matter content and to improve the physical and chemical properties of soils. Our goal is to develop management strategies that can use available organic wastes on the farm for improving soil quality for better crop production while conserving resources and preserving environmental quality. The project described here is designed to improve soil fertility by addition of composted organic wastes and to assess the contribution of nitrogen and other essential nutrients to long-term soil fertility and crop productivity in the absence of synthetic fertilizers. In our pilot project, compost was produced from wood chips derived from grounded typhoon debris and ...

Abstract: Compost application to turf grasses can increase availability of nutrients in soil and improve growth, but can potentially lead to accumulation of macronutrients in soil and contribute to leaching and runoff losses. The objectives of this study were to investigate the influence of compost source and application rate on concentrations of plant-available macronutrients in soil over 29 months after a one-time application to saint augustine grass [Stenotaphrum secundatum (Walt.) Kuntze] and Bermuda grass [Cynodon dactylon (L.) Pers.] turf. Compost application increased soil organic C, P, Ca, and S concentrations by 3 months after addition, but further increases from 3 to 29 months were seldom observed. In contrast, NO3-N and K levels declined while Mg levels increased slightly from 3 to 29 months. Seasonal or cyclical patterns of soil macronutrient levels were apparent, as lower concentrations were observed during dormant stages of Bermuda grass growth in winter. Initial macronutrient concentrations of compos...

Abstract: The aim of this research was to study different ways of nitrogen (N) fertilization and soil tillage management to ensure high yield, quality and correct usage of the available resources. Therefore, a two-year field experiment (2001 and 2003) was carried out on a sugarbeet crop grown in a Mediterranean environment to evaluate the effects of two soil tillage depths (10-15 and 40-45 cm) and of a municipal solid waste (MSW) compost application, compared to mineral N fertilization. The following fertilization treatments were compared: MSW compost at 100 kg N ha−1 (Ncom); mineral N fertilizer at 50 kg ha−1 (N50) and at 100 kg ha−1 (N100); MSW compost combined with mineral N fertilizer (Nmix) (50 kg ha−1 as organic N plus 50 kg ha−1 as mineral N); slow release organic-mineral fertilizer (Nslow) and an unfertilized control (Contr). In each trial year, growth parameters, plant and soil N indicators, yield, quality, N uptake and N efficiency, soil chemical characteristics and N mineral deficit in the soil were dete...

Abstract: Biowaste compost is frequently used in German viticulture to improve soil physical characteristics and to replace soil organic matter losses A monitoring program was carried out to investigate the effect of a mature biowaste compost application on soil biology and soil mineral N dynamics At four vineyard sites in southern Germany, compost was applied at two different rates in a random block design with four replicates Soil mineral N, soil microbial biomass and soil respiration were observed over a period of three years At three of the four investigated sites, the compost application induced a priming effect, leading to mineral N contents of between 87 and 440 kg N ha−1 shortly after the amendment During the investigation period, the pattern of N mineralization and translocation in all soils otherwise followed common rules which are governed by environmental conditions Due to the priming effect, the N release from the compost was sufficient to cover the vine's N demand for the first and second year a

Abstract: Lawn clippings were composted for 27 days to obtain an overview of chemical and biochemical changes taking place during the process. In particular, the influence of a special microbial compost starter kit (CSK) on the composting process with reference to the maturity and stability of the end-product, was studied. The starter kit consisted of an organic matrix and two seeded microorganisms, Geotrichum klebahnii and Trichoderma viride. Quality control of CSK was performed with common cultural techniques and by Polymerase Chain Reaction (PCR) using a new primer set. For temperature, electrical conductivity, spectral absorption at 254, 400 and 600 nm, and for the concentration of total organic carbon, no significant differences could be observed depending on CSK-application. In contrast, the results connected with NNH4 NNQ3, Nt, pH, percentage of dry weight and organic matter and the biomass and height of test plants pointed distinctly to better and faster degradation within the samples treated with compost s...

Abstract: In comparison to traditional windrow composting, in-vessel composting techniques often represent more effective waste management options due to the reduced production of bioaerosols and leachate and the potential for better process control. Chemical processes occurring during the cocomposting of three common wastes (green waste, biosolids and paper processing waste) were studied using the forced aeration, static pile, in-vessel EcoPOD® composting system. Since no turning of the compost occurs within the static piles, spatial differences in the vessel were also monitored. These measurements revealed significant spatial gradients in temperature; however, this did not result in spatial differences in nutrients within the composting vessel. Significant differences in soluble N production were observed during the composting process following the series: green plus paper waste < green waste < green waste plus biosolids. After the active compost phase was over, and the compost was removed from the vessel and matured outside, we demonstrated that covering the compost was essential to preserve compost quality. Our study clearly shows that cocomposting of common waste feedstocks can be used to successfully manipulate the chemistry of the final compost making it suitable for multiple end uses. In addition, our study demonstrated that careful management of the compost maturing phase is also required to maximise quality and minimize pollution.

Abstract: Advanced treatment of residues from anaerobic digestion of leftovers and kitchen waste originating from an industrial waste treatment plant was carried out by means of cocomposting in order to reveal potential synergistic effects. After a retention time of two weeks in the anaerobic reactor, microbial activity of the residues remained high. The biogas produced is of use in combined heat and power generation. Lab-scale experiments in the liquid phase have demonstrated “cracking” of the anaerobic stabilized organic matter under aerobic conditions. The advanced aerobic treatment of residues from anaerobic digestion by means of cocomposting leads to high quality composts. The addition of output material to biowaste from the separated bin collection may improve the formation of humic substances. Extractable humic acids are considered to represent a reliable parameter in describing high quality composts. Thus, the improvement of humic acid formation by means of composting is a goal to be achieved. Process contr...

Abstract: Accurate dry matter mass balance (DMMB) estimates are important if knowledge of nutrient component changes on a mass basis is required for manure handling practices. We compared four methods of estimating DMMB during composting of solid feedlot manure. A manure stockpiling treatment was included for comparison. A method which used carbon (C) concentration to calculate organic matter, and hence ash content, was most accurate and detected treatment effects. One employing changes in measured ash concentrations was also reliable, while one based on weighing material entering and leaving each handling system was prone to errors. A fourth method using changes in phosphorus (P) concentrations was less accurate. Accurate DMMB estimates greatly improve nutrient mass balance calculations which are needed to gauge the success of manure handling practices.

Abstract: The vast majority of compost research has focused on commercial-scale composting and attempts have been made previously to adapt that knowledge to amateur composting. However, amateur composting is potentially more variable and thus more difficult to generalize. This experiment used three types of amateur compost vessels and examined the effects of vessel type and turning on the resultant temperature, nutrient concentrations and physical characteristics. The effect of vessel type produced statistically significant differences in temperature as did the effect of turning the vessels. However, for all vessel types, the recorded temperatures remained in the mesophylic range and the temperatures necessary to kill pathogens or weed seeds were not reached. Observations were also made on the influence of vessel type on the physical characteristics of the resultant compost and the management of the vessels. The choice of vessel is important but it is probably more a factor of volume than design; volume appears cri...

Abstract: Ornamental nurseries extensively utilize peat in commercial soilless potting media, but its use as an organic amendment with a superior water holding capacity is challenged by economic and environmental pressures so potential alternatives to peat need to be investigated. In our experiment, commercially available peat-based soilless mixes were amended with increasing composted green waste (CGW) percentages. Results on Photinia X fraseri and Viburnum tinus suggest that CGW could partially substitute peat in containerized nursery production, with a different effectiveness related to species behavior. Viburnum seemed to be less affected by CGW addition (only CGW-based media, T100, showed a significant difference compared to peat-based media, used as control), which on the contrary hardly affected Photinia growth in terms of biomass production and quality. On the other hand, a higher CGW content (75% or 100%) also improved plant susceptibility to water shortage. Concluding, peat-based media partially amended w...

Abstract: Waste management is an increasingly important problem in many developed countries and much effort is currently being expended into identifying novel uses for waste products. We consider the effects of substituting proportions of earthworm-digested composted green waste (vermicompost) into commercial peat based growing media on the germination, growth, and productivity of Helianthus annuus, Cosmos bipinnatus and Eschscholzia californica. The percentage germination, time to flowering, seed production, overall heights and biomass were measured for all three species in treatments of commercial peat based growing media where the growth medium was substituted with vermicompost at rates of 0%, 20%, 40%, 60% and 100%. In addition, the total numbers of inflorescences was recorded in multiple flowering species. Results for Helianthus suggest that while vermicompost additions induced small species specific growth responses in germination rate, growth rate, overall height and total biomass, none were statistically si...

Abstract: The evaluation of residual organic materials as a source of enzymatic activities immobilized in the humus matrix is a little explored research area, particularly in the case of organic materials derived from municipal wastes. Enzymes catalyze most soil reactions essential for soil functionality. The advantage of humus enzyme-complexes (immobilized enzymes) with regards to free enzymes is that the former are protected in the humic colloid, being more resistant to denaturing agents and other adverse soil conditions. This explains the interest in use of organic wastes (which are produced in an increasingly amount and consequently are economical) as a source of immobilized enzymes, which could be concentrated and used to improve the quality of degraded or contaminated soils. The goal of this study was (i) to assess the potential of sewage sludge (SS) and the organic fraction of municipal solid waste (MSW), as well as their respective composts (CSS and CMSW) as sources of enzymes, (ii) to determine the proportion of such enzymes which are immobilized in the humic matrix of these organic materials, and (iii) to determine the effect of the composting process on the total and the immobilized enzymatic activities of the organic materials. Dehydrogenase (DHA), urease, protease-BAA, alkaline phosphatase (ALP), p-glucosidase (GLA) and o-diphenol oxidase (DPO) activities were determined both in the organic materials and in their humic extracts (except DHA). Sewage sludge had the highest total values of urease, protease-BAA, ALP and DHA activity (12.7 pmol NH +-N g -1 h -1 , 40.6 μmol NH + -N g -1 h -1 , 75.7 μmol PNP g -1 h -1 and 0.3 pmol INTF g -1 h -1 , respectively), which decreased with composting, but MSW had the highest total value of DPO activity. For both organic materials, a low percentage of total enzymatic activities were linked to humus (0.6-22%), except in the case of DPO activity. The SS and MSW composting process had a positive effect on the urease, protease-BAA, DPO and ALP immobilization in the humic matrix, as reflected by the higher immobilized activity/total activity ratios in the compost than in the fresh materials.

Abstract: Vermicompost made from separated swine waste solids (0, 10, or 20% by volume of soil) was applied to turnips in small field plots during four growing seasons to determine the effect on plant growth, runoff volume and nutrients in runoff. The effect of nitrogen fertilizer was controlled by supplementing half the plots with inorganic nitrogen to balance the nitrogen fertilizer recommendations for turnips. Vermicompost addition increased fresh weight of fruit and foliage by a factor of two to five and increased dry weight by a factor of three with no increase in nitrogen but higher phosphorus in runoff. Runoff volume was lower in plots that received vermicompost compared to control plots.

Abstract: Compost application to turf grasses can increase dissolved organic matter and nutrient levels in soil but may also enhance leaching and runoff losses. The objectives of this study were to determine the influence of composts on soil organic matter and accumulation of DTPA-and water-extractable Mn, Fe, Cu, and Zn in St. Augustine Grass [Stenotaphrum secundatum (Walt.) Kuntze] turf. Composts increased soil organic C (SOC) soon after application, but no further increases occurred beyond 11 months. In contrast, dissolved organic C (DOC) increased from 3 to 29 months after application, indicating contributions from decomposition of composts and St. Augustine Grass residues. Dissolved organic C was 75, 78, and 101% greater 29 months after application of 0, 80, and 160 Mg ha−1 of compost, respectively, than before application. While DTPA-extractable Mn and Cu increased from 0 to 29 months, Fe and Zn decreased and were often below background levels. By 29 months, DTPA-extractable Mn and Cu for soil receiving 160 M...

Abstract: This observational study was conducted to assess the movement of nitrate and phosphorus into and through the soil profile beneath a compacted gravel compost pad. The accumulation of nitrate and phosphorus in the vegetated filter strip immediately downslope of the pad was also evaluated. Soil samples were taken from the composting site and the immediate surrounding area in two transects each for the Control (outside of compost pad), Old Pad (combined manure stack and compost area), and Extension pad (compost only area). Each transect was divided into three sampling zones: within the pad, in an intermediate area between the pad and the filter strip, and within the filter strip. Compost samples from windrows of different ages and mixes were also taken for laboratory leaching test to determine the potential of the composts as source of nitrogen and phosphorus. The NO3-N concentrations in the soil beneath the compost pad of the Old Pad and Extension transects were higher than the soil NO3-N concentrations at t...

Abstract: Three composts from citrus-processing industry wastes, sampled at prefixed times during the composting process, were studied with the aim to follow the organic matter evolution by using the isoelectrofocusing (IEF) technique. Results indicated that IEF qualitative analyses allowed evaluation of the organic matter transformation during composting process, showing a decrease of IEF peaks focused at lower values of pH (less stabilized organic matter) and a corresponding increase of peaks focused at higher value of pH (more humified material). The parameter A %, defined as the areas sum of IEF peaks focused at pH>4.7, could be considered particularly effective as a “threshold value” to evaluate the level of organic matter evolution for the considered composts.

Abstract: Horse manure and cranberry fruit (5:1) amended with cow manure were composted in duplicate 25 m3 piles for 252 days. Piles were mixed and aerated with a front loader. Temperature was recorded at up to 80 points in each pile; it reached 74°C on day 7, and averaged >45°C through day 157. Oxygen content was measured 7 times at 27 points in each pile up to day 31, and varied from 0.1 to 13%. Volume and total mass reductions achieved were 73% and 71%, respectively, despite the addition of water on 3 occasions. The quality of the product, horse manure cranberry fruit compost (HCC), was examined on samples removed periodically from each pile and analyzed for pH, moisture, volatile solids, total carbon, nitrogen species, chemical oxygen demand of a water extract (COD), cation exchange capacity, and the ratios C/N, COD/N, C/NH4+-N, and COD/NH4+-N. The biodegradation kinetics for dry mass followed a nearly first order decay (k= 0.0187 kg/kg-day). Fecal streptococci, used as an indicator of sanitation, were reduced ...

Abstract: Sewage sludge compost and yard waste compost were compared with respect to their efficiency as biofilter material for removing ammonia from air. Ammonia removal efficiency was investigated using both small-scale filter columns in the laboratory and large-scale filter columns operated at a pig farm. The laboratory experiments were carried out using 30 cm high columns with a volume of 250 cm3 supplied with an artificially produced ammonia-air mixture, whereas 1 m columns with a volume of 27 liters supplied with the ambient air from the pig stable were used in the large-scale experiments. All filter columns were able to remove more than 95% of the ammonia in the inlet regardless of compost type and applied air flow rate. Ammonia concentration profiles inside the compost columns measured at the end of the experiments indicated that sewage sludge compost removes ammonia at significantly higher specific rates than yard waste compost. The likely explanation is that sewage sludge compost contains higher numbers o...

Abstract: A full-scale cocomposting experiment using hair wastes from the leather manufacturing industry and sewage sludge as cosubstrates was carried out with the aim of producing compost that may be used as an organic amendment in agriculture. A 1:1 weight ratio of hair wastes and sewage sludge was used based on experiments at smaller-scale. The resulting mixture was then amended with pruning wastes acting as bulking agent in a 1:1 volumetric ratio (mixture:pruning wastes). The experiment was carried out using the windrow composting technology with a weekly turning frequency. Thermophilic range of temperature was quickly achieved and maintained for more than 8 weeks. This fact ensured the sanitation of the compost according to international requirements. Additionally, the quality of the product obtained expressed in stability terms was very high (Self-heating test grade: V; respiration index: 0.83 mg O2 per gram of organic matter per hour). The nitrogen content in the final product was also high (5.6%, dry basis)...

Abstract: The composting process of organic wastes consists of the bioconversion of biologically unstable wastes to stabilized products for application to soils. This study was carried out on different soils (brown isohumic soils in Sfax region in southern Tunisia and calcimagnesic soils in Korba region in northern Tunisia). The mineralization process of organic matter is more important in isohumic soils, showing less tenors of fine fractions than in calcimagnesic soils. The study of different humic fractions in amended soils shows that humic acid tenors and the polymerization rates are linked to soil nature. Calcimagnesic soils ensure a more important humification than isohumic soils.

Abstract: Wastes were collected (cocoa husk, sugarcane bagasse, sugarcane filter cake and bovine manure) in Tabasco State, Mexico. These were vermicomposted, mixed and pretreated for temperature stabilization. The wastes were then vermicomposted with earthworms of the specie Eisenia andrei. Data were collected 60 days after the earthworms were inoculated. The vermicompost obtained was also chemically characterized. The objectives of this study were to evaluate the survival of earthworms (Sv) in several wastes and to assess the capacity of the earthworms to produce vermicompost (Vp). Waste with high C/N ratio had lower Vp, although the Sv was not affected. The C/N ratio was closely associated with the quality of organic matter (OM); when wastes had high content of nitrogen compounds, the C/N ratio decreased. The integration of cocoa husk in the treatment improved Sv, while the mixture of filter cake and bovine manure (1:1) was the optimum treatment for Vp. Important changes concerning the chemical characteristics of the vermicompost due to the influence of earthworms were not observed.

Abstract: In Montreal, Quebec, many dogs are exercised in fenced-in runs in parks. Consequently, these dog parks are a high-density source of large amounts of dog waste, which is typically collected by the owner in a plastic bag and deposited in the municipal garbage. In 2004, an experimental large-scale dog waste composting programme was initiated at the Notre-Dame-de-Grâce (NDG) dog run in Montreal, Quebec. Dog waste was collected with plastic shovels, deposited into compost bins, and layered with sawdust. In two months, a total of 213kg (470 lbs) of dog waste was collected and composted, along with 33kg (72 lbs) of donated sawdust, in two research compost bins. After a year of incubation, the two bins produced 179kg (394 lbs) of compost. Temperatures in the research bins peaked between 40°C and 55°C but were not maintained long enough for conclusive elimination of pathogens. Participation by dog run users during the trial project was enthusiastic, and full-scale dog waste composting has now been implemented at t...

Abstract: A comparative study of the physical, chemical and microbial properties of 12 composts sourced from United Kingdom commercial composting plants was carried out. The aim was to ascertain whether these composts could be used as growing media or for application to agricultural land. The composts were produced from either source segregated biodegradable municipal waste (BMW) or mixed municipal solid waste (MSW). Ten composts contained 100% source segregated BMW including green, fruit, vegetable, meat and kitchen waste, paper and cardboard. One compost was 72% mixed MSW plus 18% source segregated BMW, and one compost was 100% mixed MSW. Composts were analyzed for pH, electrical conductivity, carbohydrates, nutrients and contaminants. The composts sourced from mixed MSW contained higher levels of physical contaminants (glass, plastic and metal) than the source segregated BMW composts. Nitrogen concentrations (as % dry weight) were 1.7-2.2% where kitchen or meat waste was included and 1.0-1.6% otherwise. Phosphor...