The fact that Morocco is an agricultural country and the large volume of biodegradable waste produced by the population make composting so important.The degradation of organic matter is facilitated by faunal and flora...The fact that Morocco is an agricultural country and the large volume of biodegradable waste produced by the population make composting so important.The degradation of organic matter is facilitated by faunal and floral macro and micro-organisms that act in different stages of maturation;studies on this fauna are quite rare both nationally and internationally.On a sample of two tons of household waste,we documented invertebrates that colonized compost heaps and then assessed the changes in the structure of the invertebrate population during the different phases.Our study revealed the presence of several zoological groups colonizing the compost heaps during the different composting phases;we noted the presence of:(1)Macroscopic invertebrates,in order of number of individuals:insect larvae,ants,earthworms,sowbugs,spiders,springtails,and millipedes,and(2)Microscopic invertebrates,the most abundant in terms of individuals:mites and nematodes.As for the order of appearance,we observed that insect larvae were the first to colonize the compost heap from the very first days of installation,followed by woodlice observed during the thermophilic phase and disappearing towards the end of the process.Earthworms were observed during the end of the thermophilic phase,while springtails were observed more during the cooling and maturation phases.Our study revealed the presence of a good quality of fauna during the composting process,which are indicators of good compost quality and play a major role in the circulation of nutrients,thus ensuring the provision of essential elements for plant nutrition.展开更多
Enhancing A.bisporus L.culture media with nanomaterials and some biostimulants is important for in improving mushroom productivity quantitatively and qualitatively.Magnetic iron nanoparticles(N-FeO),carbon nanotube(CN...Enhancing A.bisporus L.culture media with nanomaterials and some biostimulants is important for in improving mushroom productivity quantitatively and qualitatively.Magnetic iron nanoparticles(N-FeO),carbon nanotube(CNTs)suspensions,effective microorganisms(EM)bio-fertilisers,and growth stimulants(Atonik)were used individually and in combination to enhance the compost culture media.Quantitative and qualitative traits of the mushroom yield were measured.In a simple oOne-Wway experiment that included 16 treatments—Ssingle agents,two-,three-,and four-way Ccombinations and three replications—,the statistical analysis results of Duncan’'s test showed.Tthat the individual impact of the applied study treatments and their combined synergistic effects resulted in a significant increase in the traits of the number of fruiting bodies,fruiting body rate,yield quantity,mushroom biological efficiency ratio,stem length,stem diameter,head diameter,head thickness,carbohydrates content,protein content,ash,and dry matter.The application of Atonik itself resulted in the highest values of fruiting body number,yield,biological efficiency,and stem length,which were respectively were 128.33 body bags^(-1),2814 g bag-1,37.52%,and 3.03 cm,compared to the control of 32.33 body bags^(-1),749 g bag-1,9.98%,and 1.72 cm.The treatments NFeO+CNT+EM+ATO resulted in a significant increase in the traits of the fruiting body rate,stem length,and carbohydrate content by 32.69 g,3.40 cm,and 16.78%,respectively,compared to the control of 22.97 g,1.72 cm,and 8.16%,respectively.展开更多
Soil organic amendments(OAs)are used to replenish carbon(C)and nutrients in the soil to prevent its degradation and increase its fertility.While soil can be an important C sink,it can also release significant amounts ...Soil organic amendments(OAs)are used to replenish carbon(C)and nutrients in the soil to prevent its degradation and increase its fertility.While soil can be an important C sink,it can also release significant amounts of greenhouse gases(GHGs).Different OA pretreatment technologies indirectly affect soil aggregate formation and C stabilization even when the same initial substrate is used.However,little is known about the long-term effect of OA pretreatment on the soil C and nitrogen(N)associated with macroaggregates,which are known to disintegrate faster than microaggregates.In this study,we studied the effect of OA pretreatment on soil C and N in relation to aggregate formation and GHG emissions using five differently pretreated OAs from the same original OA,i.e.,composted,digested,and fermented OA,a 1:1 mix of the composted and fermented OAs,and the unpretreated original OA.We monitored the changes in a soil column experiment after 6 and 12 months of incubation.Our results indicated that OA pretreatment indirectly affected GHG emissions from soil.The composted and mixed OAs released less GHGs(i.e.,carbon dioxide,nitrous oxide,and methane)but had no positive impact on macroaggregates,while the digested OA induced long-lasting macroaggregation and occluded particulate organic matter formation,emitting intermediate levels of GHGs.The unpretreated OA exhibited the highest GHG emissions,similar to the fermented OA,albeit without benefiting macroaggregation.These demonstrated that OA pretreatment had a long-lasting indirect effect on soil C and N,influencing total GHG emissions,nitrous oxide formation mechanisms,and soil macroaggregate formation.展开更多
Rice straw,which is produced after the harvest of rice,is a major agricultural waste in the world.Rice straw has a high carbon/nitrogen ratio and is more resistant to microbial degradation than other straws because it...Rice straw,which is produced after the harvest of rice,is a major agricultural waste in the world.Rice straw has a high carbon/nitrogen ratio and is more resistant to microbial degradation than other straws because its main constituents are cellulose and hemicelluloses encrusted by lignin.When rice straw is burned,hazardous substances such as carbon dioxide,methane,carbon monoxide,and nitrogen monoxide are released into the air as smoke(less than 10μm-sized particles).The rise in the burning of rice straw has contributed to too many accidents and health issues in the general population residing in Haryana,Punjab,and Uttar Pradesh of India.These states are being urged by the National Green Tribunal to generate money instead of burning rice straw.Even though these lignocellulosic materials might be beneficial,not much has been carried out with them.This overview covers the properties of rice straw and husks,the numerous procedures used to create valuable products,and various applications that may be made for them.These include energy sources,environmental adsorbents,building supplies,and specialist commodities.展开更多
To determine the addition amount of Phellodendri Chinensis Cortex residue for composting,this study designed four Phellodendri Chinensis Cortex residue treatments of 100(A1),150(A2),200(A3),and 250(A4).Then,mushroom s...To determine the addition amount of Phellodendri Chinensis Cortex residue for composting,this study designed four Phellodendri Chinensis Cortex residue treatments of 100(A1),150(A2),200(A3),and 250(A4).Then,mushroom substrate residue,rice husks,and pig manure were added,and the cellulose-degrading strain ZG2-3 was inoculated at 5%for composting.The inoculation of a commercially available microbial agent was taken as the positive control(PC),and no inoculation of microbial agent as the blank control(CK).The effect of different treatments on the heavy metal content,nutrients,physicochemical properties,and microbial counts of compost and the seed germination index(GI)were studied and compared.The results showed that except that in CK,the content of heavy metals in other treatments did not exceed the standard limits.With the increase in the addition amount of Phellodendri Chinensis Cortex residue,the content of available nitrogen,available phosphorus,available potassium,and total nutrients in the compost also increased.Adding microbial agent significantly increased the content of total nutrients,available nitrogen,available phosphorus,available potassium,total nitrogen,total phosphorus,and total potassium in the compost,while reducing the content of organic matter.The GI was the highest in A4 treatment,reaching 85.33%,and it followed a trend of A3>PC>CK.This indicated that the inoculation of microbial agent accelerated the maturation of compost,and ZG2-3 outperformed the commercially available Bacillus subtilis.Overall,the A4 treatment(250 g Phellodendri Chinensis Cortex residue+125 g mushroom substrate residue+125 g rice husks+1000 g pig manure+inoculation of 5%ZG2-3)performed well in terms of nutrients content,physicochemical properties,and GI and had good safety,being the optimal formula for composting.展开更多
Although the efficiency of poly(ethylene terephthalate)(PET)degradation has been successfully improved by depolymerase engineering,mostly by using Goodfellow-PET(gf-PET)as a substrate,efforts to degrade unpretreated P...Although the efficiency of poly(ethylene terephthalate)(PET)degradation has been successfully improved by depolymerase engineering,mostly by using Goodfellow-PET(gf-PET)as a substrate,efforts to degrade unpretreated PET materials with high crystallinity remain insufficient.Here,we endeavored to improve the degradation capability of a WCCG mutant of leaf-branch compost cutinase(LCC)on a unpretreated PET substrate(crystallinity>40%)by employing iterative saturation mutagenesis.Using this method,we developed a high-throughput screening strategy appropriate for unpretreated substrates.Through extensive screening of residues around the substrate-binding groove,two variants,WCCG-sup1 and WCCG-sup2,showed good depolymerization capabilities with both high-(42%)and low-crystallinity(9%)substrates.The WCCG-sup1 variant completely depolymerized a commercial unpretreated PET product in 36 h at 72℃.In addition to enzyme thermostability and catalytic efficiency,the adsorption of enzymes onto substrates plays an important role in PET degradation.This study provides valuable insights into the structure-function relationship of LCC.展开更多
[Objective] The aim of this study was to explore the sterilization effects on Escherichia coli by adding bacterial inhibitor(CaCN2)during the process of cattle manure composting so as to provide a theoretical basis fo...[Objective] The aim of this study was to explore the sterilization effects on Escherichia coli by adding bacterial inhibitor(CaCN2)during the process of cattle manure composting so as to provide a theoretical basis for cattle manure harmless treatment.[Method] Both experimental groups supplemented with 2.0% bacterial inhibitor and control groups without bacterial inhibitor were cultured under different temperatures(20,30,37,50,60 ℃)to determine the optimal composing temperature.Under 30 ℃,different bacterial inhibitor doses(0,2.0%,2.5%,3.0%)were added into the compost to obtain the optimal bacterial inhibitor addition dose.[Result] 30,50 and 60 ℃ were ideal temperatures for sterilization of E.coli.Under 30 ℃,E.coli couldn't be detected in 2.5% dose group and 3.0% dose group after culture for 48 h,demonstrating no less than 2.5% bacterial inhibitor should be added.[Conclusion] It has an important significance to enhance the sterilization effects on E.coli by adding CaCN2 into cattle manure compost especially in winter.展开更多
[Objective] The aim was to study change of the composition of cow dung compost by adding complex enzyme.[Method] 2.0% enzyme treatment group,1.5% enzyme treatment group and control group were set to analyze temperatur...[Objective] The aim was to study change of the composition of cow dung compost by adding complex enzyme.[Method] 2.0% enzyme treatment group,1.5% enzyme treatment group and control group were set to analyze temperature,moisture,pH value,crude fiber,TOC,TN,GI during composting.[Result] The results showed that adding complex enzymes could accelerate degradation of organic matter in pre-composting period.Crude fiber of 2.0%,.1.5% enzyme treatment group and control group decreased 49.6%,47% and 29.1% respectively,TOC decreased 41.7%,35.3% and 21.1%,TN decreased 32.6%,26.8% and 19.2%.2.0%,1.5% enzyme treatment groups could reach basic maturity degree at 30 d.[Conclusion] Composting cycle be shortened by adding complex enzymes,which was useful for maturity of cow dung compost.展开更多
[Objective] The purpose was to study the optimum composition ratio of compound substrate with spent mushroom compound （SMC） and cattle manure com- post （CMC） for the seedling growth of tomato, cucumber and waterme...[Objective] The purpose was to study the optimum composition ratio of compound substrate with spent mushroom compound （SMC） and cattle manure com- post （CMC） for the seedling growth of tomato, cucumber and watermelon. [Method] With internationally best formula substrate （turf：vermiculite=2：1） used for CK, SMC and CMC were matched according to different proportions to get different substrate whose physical and chemical nutrient properties and their effects on the growth of tomato, cucumber and watermelon were studied by means of plug seeding technolo- gy. [Result] The results showed that the bulk density, porosity and the pH of the compound substrates are all in the ideal condition. However, CMC increased the EC value and the pH of the compound substrates. Compound substrates with high ratio of CMC are not suitable for seedlings. [Conclusion] Tomato and watermelon seedlings grew well in the compost substrate with SMC：CMC=3：1 with no river sand. And the cucumber seedlings grew well in the compost substrate with SMC：CMC=2：1 with 5% volume river sand.展开更多
To study the effects of superphosphate（SP） on the NH_3 and greenhouse gas emissions,vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls,five vegetable waste...To study the effects of superphosphate（SP） on the NH_3 and greenhouse gas emissions,vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls,five vegetable waste mixtures（0.77m^3 each） were treated with different amounts of the SP additive, namely, 5%, 10%,15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting.Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH_3 emission by 4.0% to 16.7%. The total greenhouse gas emissions（CO_2-eq） of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH_3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases.The amount of NH_3（CO_2-eq）from each treatment ranged from 59.90 to 81.58 kg/t; NH_3（CO_2-eq） accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH_3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer.展开更多
[Objective] This study aimed to investigate the adsorption properties of the adsorption tower filled with calcium superphosphate on ammonia volatilized with aer- ation. [Method] Adsorption tower filled with calcium su...[Objective] This study aimed to investigate the adsorption properties of the adsorption tower filled with calcium superphosphate on ammonia volatilized with aer- ation. [Method] Adsorption tower filled with calcium superphosphate was adopted as experimental apparatus, which was constructed by poly vinyl chloride （PVC） circular tubes. With hartshorn as the source of ammonia volatilization, the effect of different ratios of height to diameter of the tower filled with equal amount of calcium super-phosphate on ammonia adsorption was investigated. In addition, adsorption tower with height-diameter ratio of 9.9 was selected to adsorb the ammonia emitted from the composting systems of pig manure and chicken manure with optimized and reg- ulated carbon-nitrogen ratio. [Result] Under certain volatilization rate, calcium super- phosphate particles in the adsorption tower could effectively adsorb the ammonia, and the adsorption efficiency was enhanced with the increase of height-diameter ra-tio, which could reach above 90% with height-diameter ratio of more than 1.1; the ammonia emitted from composting systems of pig manure and chicken manure with optimized and regulated carbon-nitrogen ratio could be completely absorbed using adsorption tower with height-diameter ratio of 9.9 filled with calcium superphosphate accounting for about 8% of the weight of composting materials. [Conclusion] Experi- mental results of this study provided reference for the application of adsorption tower filled with calcium superphosphate in the treatment of waste gas emitted from com- posting materials.展开更多
This study aimed to investigate the bacterial communities in mushroom compost piles composed of rice straw, corn stover, and cow dung. Bacterial com- munities of samples at the beginning of composting, at the end of f...This study aimed to investigate the bacterial communities in mushroom compost piles composed of rice straw, corn stover, and cow dung. Bacterial com- munities of samples at the beginning of composting, at the end of fermentation phase I and II were collected and analyzed using Polymerase Chain Reaction-De- naturing Gradient Gel Electrophoresis （PCR-DGGE） based on 16S rDNA universal primers from Escherichia coli. A total of 56 different clone sequences were obtained （GenBank accession number： KF630598-KF630653）. They were classified into seven phyla and 42 genera. Dominant microflora during composting belonged to phylum Proteobacteria, Firmicutes, and Actinobacteria, with the dominant genera of Bacillus, Paenibacillus, Thermomonospora, Thermasporomyces, Pseudomonas, and Cellvibrio. Bacterial diversity （Shannon index） analysis showed that bacterial species in com- post pile composed mainly of rice straw continuously increased during composting, while those in compost pile composed mainly of corn stover firstly increased and then reduced. Principal component analysis showed that corn stover compost sam- ples at the end of fermentation phase I and phase II were clustered into one group, suggesting that corn stover composted faster than anticipated. In general, rice straw compost has higher bacterial diversity but longer composting time period, while corn stover compost has lower bacterial diversity but shorter composting time period.展开更多
Development of home compostable materials based on bioavailable polymers is of high strategic interest as they ensure a significant reduction of the environmental footprint in many production sectors.In this work,the ...Development of home compostable materials based on bioavailable polymers is of high strategic interest as they ensure a significant reduction of the environmental footprint in many production sectors.In this work,the addition of thermoplastic starch to binary PLA/PBAT blends was studied.The compounds were obtained by a reactive extrusion process by means of a co-rotating twin screw extruder.Thermomechanical,physical and chemical characterization tests were carried out to highlight the effectiveness of the material design strategy.The compounds were subsequently reprocessed by cast extrusion and thermoforming in order to obtain products suitable for the storage of hot food.The extruded films and the thermoformed containers were further characterized to highlight their thermo-mechanical,physical and chemical properties.Thermo-rheological,mechanical and physical properties of the material and of the cast film were analyzed thoroughly using combined technique as capillary rheometer,MFI,DSC,VICAT/HDT,XRD,FTIR,UV-Vis,SEM,permeability and,lastly,running preliminary chemical inertness and biodegradation tests.Particular attention was also devoted to the evaluation of the thermo-mechanical resistance of the thermoformed containers,where the PLA/PBAT/TPS blends proved to be very effective,also presenting a high disintegration rate in ambient conditions.展开更多
[Objective] In order to study the influence of bacteria and accessories of chicken manure compost.[Method] The experiment was conducted to investigate the changes of temperature,the quantification of Escherichia coli ...[Objective] In order to study the influence of bacteria and accessories of chicken manure compost.[Method] The experiment was conducted to investigate the changes of temperature,the quantification of Escherichia coli and the odor during chicken manure compost by adding sawdust,rice husk,yeast and lactic acid bacteria respectively.[Result] The results showed that：（1） The yeast group reached the highest fermentation temperature 67.6 ℃,which was 6.9 ℃ higher than that of lactic acid bacteria group,and the fermentation time of yeast group kept over 55 ℃for 16 days,which was 5 days longer than that of lactic acid bacteria group,both of which were better than that of control group（55.9 ℃,5 days）;（2）The highest fermentation temperature of sawdust group was 2.2 ℃ higher than that of rice husk group,and the fermentation time of sawdust group kept over 55 ℃ was 3 days longer than that of rice husk group;（3） The quantification of E.coli reduced from10^5 to 10^2per gram in both of the yeast group and the lactic acid bacteria group.The odor of the yeast group and the lactic acid bacteria group disappeared in the seventh day and the eighth day respectively.[Conclusion] The results showed that the adding of yeast and sawdust was the best condition for chicken manure composting in this experiment.展开更多
In order to investigate the influence of secondary classification mode on waste generation features, this study classified domestic waste generated by 310 rural and urban households at urban areas and Shuigaozhuang Vi...In order to investigate the influence of secondary classification mode on waste generation features, this study classified domestic waste generated by 310 rural and urban households at urban areas and Shuigaozhuang Village of Xiqing District into 3 groups： compostable materials, recyclable materials and toxics on the basis of the constructed secondary classification mode of domestic waste. The study focused on waste generation strength and classification features, compared the waste generation features between rural and urban residents, and analyzed the re- lation between waste generation strength and economic and cultural factors. The re- sults indicated that the average generation speed of urban domestic waste was 423.08 g/（d.capita）, and that of rural domestic waste was 629.89 g/（d.capita）, there was significant difference between rural and urban compost generation strength （P= 0.00002）, while the generation strength of recyclable materials and toxics between rural and urban areas had no significant difference （P=0.471 and P=0.099, respec- tively）. Secondary classification mode is an effective source classification mode for domestic wastes and has positive effects on waste reduction and treatment.展开更多
Polyethylene (PE) films with additives consisting mainly of oleic acid and ferrous ions were subjected to accelerated degradation at simulated composting temperatures.Based on Fourier transform infrared spectroscopy a...Polyethylene (PE) films with additives consisting mainly of oleic acid and ferrous ions were subjected to accelerated degradation at simulated composting temperatures.Based on Fourier transform infrared spectroscopy and measurements of mechanical properties and viscosity average molecular weight,the degradation of the films was characterized and the degradation mechanism was discussed.The films containing additives with ferrous ions represent considerable decreases in molecular weight,and the carbonyl groups and hydroperoxides in the aging films show different trends of increase with the aging time.These results indicate that the ferrous ion plays an important role in the degradation of PE films and accelerates the degradation of PE.展开更多
The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost...The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost environment.The mechanical properties,viscosity average molecular weight (M η) of PE and hydroperoxide (POOH) concentration in the samples were measured.FT IR and DSC were also applied to characterize some samples.It was shown that the above mentioned metallic organic compounds can catalyze the degradation of LDPE efficiently.After 2 months aging,all samples with catalysts became fragile and the M η of the material decreased dramatically.Furthermore,the concentration of carbonyl and the degree of crystallinity of the material increased with the aging time.展开更多
Gaseous emission （N2O, CH4 and NH3） from composting can be an important source of anthropogenic greenhouse gas and air pollution. A laboratory scale orthogonal experiment was conducted to estimate the effects of C/N...Gaseous emission （N2O, CH4 and NH3） from composting can be an important source of anthropogenic greenhouse gas and air pollution. A laboratory scale orthogonal experiment was conducted to estimate the effects of C/N ratio, aeration rate and initial moisture content on gaseous emission during the composting of pig faeces from Chinese Ganqinfen system. The results showed that about 23.9% to 45.6% of total organic carbon （TOC） was lost in the form of CO2 and 0.8% to 7.5% of TOC emitted as CH4. Most of the nitrogen was lost in the form of NH3, which account for 9.6% to 32.4% of initial nitrogen. N20 was also an important way of nitrogen losses and 1.5% to 7.3% of initial total nitrogen was lost as it. Statistic analysis showed that the aeration rate is the most important factor which could affect the NH3 （p = 0.0189）, CH4 （p = 0.0113） and N20 （p = 0.0493） emissions significantly. Higher aeration rates reduce the CH4 emission but increase the NH3 and N20 losses. C/N ratio could affect the NH3 （p = 0.0442） and CH4 （p = 0.0246） emissions significantly, but not the N20. Lower C/N ratio caused higher NH3 and CH4 emissions. The initial moisture content can not influence the gaseous emission significantly. Most treatments were matured after 37 days, except a trial with high moisture content and a low C/N ratio.展开更多
Laboratory simulation studies and composting pilot study wereconducted to evaluate the capacity of three strains of fungi,indigenous fungus Fusarium sp. And Phanerochaete chrysosporium andCoriolus Versicolor, to remed...Laboratory simulation studies and composting pilot study wereconducted to evaluate the capacity of three strains of fungi,indigenous fungus Fusarium sp. And Phanerochaete chrysosporium andCoriolus Versicolor, to remediate petroleum-contaminated soils. Inlaboratory, the fungi were inoculated into a liquid Culture mediumand the petroleum-contaminated soil samples for incubation of 40 and50 days, respectively. In the 200-day pilot study, nutrient contentsand moisture were adjusted and maintained under aerobic Condition incomposting units using concrete container (118.5 cm×65.5 cm×12.5cm) designed specially For this study.展开更多
The aim of this study was to characterize the biological stability and maturity degree of compost during a controlled pile-composting trial of mixed vegetable residues （VR） collected from markets of Tunis City with ...The aim of this study was to characterize the biological stability and maturity degree of compost during a controlled pile-composting trial of mixed vegetable residues （VR） collected from markets of Tunis City with residues of Posidonia oceanica （PoR）, collected from Tunis beaches. The accumulation in beaches （as well as their removal） constitutes a serious environmental problem in all Mediterranean countries particularly in Tunisia. Aerobic-thermophilic composting is the most reasonable way to profit highly-valuable content of organic matter in these wastes for agricultural purposes. The physical, chemical, and biological parameters were monitored during composting over 150 d. The most appropriate parameters were selected to establish the maturity degree. The main result of this research was the deduction of the following maturity criterion： （a） C/N ratio 〈 15; （b） NH4^＋-N 〈 400 mg/kg; （c） CO2-C 〈 2000 mg CO2-C/kg; （d） dehydrogenase activity 〈 1 mg TPF/g dry matter; （e） germination index （GI） 〉 80%. These five parameters, considered jointly are indicative of a high maturity degree and thus of a high-quality organic amendment which employed in a rational way, may improve soil fertility and soil quality. The mature compost was relatively rich in N （13.0 g/kg）, P （4.74 g/kg） and MgO （15.80 g/kg）. Thus composting definitively constitutes the most optimal option to exploit these wastes.展开更多
文摘The fact that Morocco is an agricultural country and the large volume of biodegradable waste produced by the population make composting so important.The degradation of organic matter is facilitated by faunal and floral macro and micro-organisms that act in different stages of maturation;studies on this fauna are quite rare both nationally and internationally.On a sample of two tons of household waste,we documented invertebrates that colonized compost heaps and then assessed the changes in the structure of the invertebrate population during the different phases.Our study revealed the presence of several zoological groups colonizing the compost heaps during the different composting phases;we noted the presence of:(1)Macroscopic invertebrates,in order of number of individuals:insect larvae,ants,earthworms,sowbugs,spiders,springtails,and millipedes,and(2)Microscopic invertebrates,the most abundant in terms of individuals:mites and nematodes.As for the order of appearance,we observed that insect larvae were the first to colonize the compost heap from the very first days of installation,followed by woodlice observed during the thermophilic phase and disappearing towards the end of the process.Earthworms were observed during the end of the thermophilic phase,while springtails were observed more during the cooling and maturation phases.Our study revealed the presence of a good quality of fauna during the composting process,which are indicators of good compost quality and play a major role in the circulation of nutrients,thus ensuring the provision of essential elements for plant nutrition.
文摘Enhancing A.bisporus L.culture media with nanomaterials and some biostimulants is important for in improving mushroom productivity quantitatively and qualitatively.Magnetic iron nanoparticles(N-FeO),carbon nanotube(CNTs)suspensions,effective microorganisms(EM)bio-fertilisers,and growth stimulants(Atonik)were used individually and in combination to enhance the compost culture media.Quantitative and qualitative traits of the mushroom yield were measured.In a simple oOne-Wway experiment that included 16 treatments—Ssingle agents,two-,three-,and four-way Ccombinations and three replications—,the statistical analysis results of Duncan’'s test showed.Tthat the individual impact of the applied study treatments and their combined synergistic effects resulted in a significant increase in the traits of the number of fruiting bodies,fruiting body rate,yield quantity,mushroom biological efficiency ratio,stem length,stem diameter,head diameter,head thickness,carbohydrates content,protein content,ash,and dry matter.The application of Atonik itself resulted in the highest values of fruiting body number,yield,biological efficiency,and stem length,which were respectively were 128.33 body bags^(-1),2814 g bag-1,37.52%,and 3.03 cm,compared to the control of 32.33 body bags^(-1),749 g bag-1,9.98%,and 1.72 cm.The treatments NFeO+CNT+EM+ATO resulted in a significant increase in the traits of the fruiting body rate,stem length,and carbohydrate content by 32.69 g,3.40 cm,and 16.78%,respectively,compared to the control of 22.97 g,1.72 cm,and 8.16%,respectively.
基金funded by the Dutch Ministry of Economic Affairs and Climate Policy,the European Union Regional Development Fund,the City of Leeuwarden,the Province of Fryslân,the Northern Netherlands Provinces and The Netherlands Organization for Scientific Research.Wetsus also coordinates the WaterSEED project,which received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement(No.665874)。
文摘Soil organic amendments(OAs)are used to replenish carbon(C)and nutrients in the soil to prevent its degradation and increase its fertility.While soil can be an important C sink,it can also release significant amounts of greenhouse gases(GHGs).Different OA pretreatment technologies indirectly affect soil aggregate formation and C stabilization even when the same initial substrate is used.However,little is known about the long-term effect of OA pretreatment on the soil C and nitrogen(N)associated with macroaggregates,which are known to disintegrate faster than microaggregates.In this study,we studied the effect of OA pretreatment on soil C and N in relation to aggregate formation and GHG emissions using five differently pretreated OAs from the same original OA,i.e.,composted,digested,and fermented OA,a 1:1 mix of the composted and fermented OAs,and the unpretreated original OA.We monitored the changes in a soil column experiment after 6 and 12 months of incubation.Our results indicated that OA pretreatment indirectly affected GHG emissions from soil.The composted and mixed OAs released less GHGs(i.e.,carbon dioxide,nitrous oxide,and methane)but had no positive impact on macroaggregates,while the digested OA induced long-lasting macroaggregation and occluded particulate organic matter formation,emitting intermediate levels of GHGs.The unpretreated OA exhibited the highest GHG emissions,similar to the fermented OA,albeit without benefiting macroaggregation.These demonstrated that OA pretreatment had a long-lasting indirect effect on soil C and N,influencing total GHG emissions,nitrous oxide formation mechanisms,and soil macroaggregate formation.
文摘Rice straw,which is produced after the harvest of rice,is a major agricultural waste in the world.Rice straw has a high carbon/nitrogen ratio and is more resistant to microbial degradation than other straws because its main constituents are cellulose and hemicelluloses encrusted by lignin.When rice straw is burned,hazardous substances such as carbon dioxide,methane,carbon monoxide,and nitrogen monoxide are released into the air as smoke(less than 10μm-sized particles).The rise in the burning of rice straw has contributed to too many accidents and health issues in the general population residing in Haryana,Punjab,and Uttar Pradesh of India.These states are being urged by the National Green Tribunal to generate money instead of burning rice straw.Even though these lignocellulosic materials might be beneficial,not much has been carried out with them.This overview covers the properties of rice straw and husks,the numerous procedures used to create valuable products,and various applications that may be made for them.These include energy sources,environmental adsorbents,building supplies,and specialist commodities.
文摘To determine the addition amount of Phellodendri Chinensis Cortex residue for composting,this study designed four Phellodendri Chinensis Cortex residue treatments of 100(A1),150(A2),200(A3),and 250(A4).Then,mushroom substrate residue,rice husks,and pig manure were added,and the cellulose-degrading strain ZG2-3 was inoculated at 5%for composting.The inoculation of a commercially available microbial agent was taken as the positive control(PC),and no inoculation of microbial agent as the blank control(CK).The effect of different treatments on the heavy metal content,nutrients,physicochemical properties,and microbial counts of compost and the seed germination index(GI)were studied and compared.The results showed that except that in CK,the content of heavy metals in other treatments did not exceed the standard limits.With the increase in the addition amount of Phellodendri Chinensis Cortex residue,the content of available nitrogen,available phosphorus,available potassium,and total nutrients in the compost also increased.Adding microbial agent significantly increased the content of total nutrients,available nitrogen,available phosphorus,available potassium,total nitrogen,total phosphorus,and total potassium in the compost,while reducing the content of organic matter.The GI was the highest in A4 treatment,reaching 85.33%,and it followed a trend of A3>PC>CK.This indicated that the inoculation of microbial agent accelerated the maturation of compost,and ZG2-3 outperformed the commercially available Bacillus subtilis.Overall,the A4 treatment(250 g Phellodendri Chinensis Cortex residue+125 g mushroom substrate residue+125 g rice husks+1000 g pig manure+inoculation of 5%ZG2-3)performed well in terms of nutrients content,physicochemical properties,and GI and had good safety,being the optimal formula for composting.
文摘Although the efficiency of poly(ethylene terephthalate)(PET)degradation has been successfully improved by depolymerase engineering,mostly by using Goodfellow-PET(gf-PET)as a substrate,efforts to degrade unpretreated PET materials with high crystallinity remain insufficient.Here,we endeavored to improve the degradation capability of a WCCG mutant of leaf-branch compost cutinase(LCC)on a unpretreated PET substrate(crystallinity>40%)by employing iterative saturation mutagenesis.Using this method,we developed a high-throughput screening strategy appropriate for unpretreated substrates.Through extensive screening of residues around the substrate-binding groove,two variants,WCCG-sup1 and WCCG-sup2,showed good depolymerization capabilities with both high-(42%)and low-crystallinity(9%)substrates.The WCCG-sup1 variant completely depolymerized a commercial unpretreated PET product in 36 h at 72℃.In addition to enzyme thermostability and catalytic efficiency,the adsorption of enzymes onto substrates plays an important role in PET degradation.This study provides valuable insights into the structure-function relationship of LCC.
基金Supported by Key Project of Natural Science Foundation of Inner Mongolia Autonomous Region(200607010403)National Key Project of Scientific and Technical Supporting Programs Funded by Ministry of Science&Technology of China(2006BAD04A15)~~
文摘[Objective] The aim of this study was to explore the sterilization effects on Escherichia coli by adding bacterial inhibitor(CaCN2)during the process of cattle manure composting so as to provide a theoretical basis for cattle manure harmless treatment.[Method] Both experimental groups supplemented with 2.0% bacterial inhibitor and control groups without bacterial inhibitor were cultured under different temperatures(20,30,37,50,60 ℃)to determine the optimal composing temperature.Under 30 ℃,different bacterial inhibitor doses(0,2.0%,2.5%,3.0%)were added into the compost to obtain the optimal bacterial inhibitor addition dose.[Result] 30,50 and 60 ℃ were ideal temperatures for sterilization of E.coli.Under 30 ℃,E.coli couldn't be detected in 2.5% dose group and 3.0% dose group after culture for 48 h,demonstrating no less than 2.5% bacterial inhibitor should be added.[Conclusion] It has an important significance to enhance the sterilization effects on E.coli by adding CaCN2 into cattle manure compost especially in winter.
基金Supported by National Science and Technology Support Program"Key Technology Integration Research and Demonstration in the High-efficiency Production Mode of Farmland Cycle "(2007BAD89B16)~~
文摘[Objective] The aim was to study change of the composition of cow dung compost by adding complex enzyme.[Method] 2.0% enzyme treatment group,1.5% enzyme treatment group and control group were set to analyze temperature,moisture,pH value,crude fiber,TOC,TN,GI during composting.[Result] The results showed that adding complex enzymes could accelerate degradation of organic matter in pre-composting period.Crude fiber of 2.0%,.1.5% enzyme treatment group and control group decreased 49.6%,47% and 29.1% respectively,TOC decreased 41.7%,35.3% and 21.1%,TN decreased 32.6%,26.8% and 19.2%.2.0%,1.5% enzyme treatment groups could reach basic maturity degree at 30 d.[Conclusion] Composting cycle be shortened by adding complex enzymes,which was useful for maturity of cow dung compost.
基金Supported by Non-profit Industrial Project of Agricultural Ministry--Research and Demonstration of Integrated and Assorted Technological System on Agricultural Clean Production and Recycling Use of Rural Waste(200903011)~~
文摘[Objective] The purpose was to study the optimum composition ratio of compound substrate with spent mushroom compound （SMC） and cattle manure com- post （CMC） for the seedling growth of tomato, cucumber and watermelon. [Method] With internationally best formula substrate （turf：vermiculite=2：1） used for CK, SMC and CMC were matched according to different proportions to get different substrate whose physical and chemical nutrient properties and their effects on the growth of tomato, cucumber and watermelon were studied by means of plug seeding technolo- gy. [Result] The results showed that the bulk density, porosity and the pH of the compound substrates are all in the ideal condition. However, CMC increased the EC value and the pH of the compound substrates. Compound substrates with high ratio of CMC are not suitable for seedlings. [Conclusion] Tomato and watermelon seedlings grew well in the compost substrate with SMC：CMC=3：1 with no river sand. And the cucumber seedlings grew well in the compost substrate with SMC：CMC=2：1 with 5% volume river sand.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303089-2)Agricultural Eco-environment Protection Program of Ministry of Agriculture in 2014+1 种基金Key Agricultural Applied Technology Innovation Project of Shandong Province in 2015Shandong Academy of Agricultural Sciences(2014QNM21)~~
文摘To study the effects of superphosphate（SP） on the NH_3 and greenhouse gas emissions,vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls,five vegetable waste mixtures（0.77m^3 each） were treated with different amounts of the SP additive, namely, 5%, 10%,15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting.Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH_3 emission by 4.0% to 16.7%. The total greenhouse gas emissions（CO_2-eq） of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH_3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases.The amount of NH_3（CO_2-eq）from each treatment ranged from 59.90 to 81.58 kg/t; NH_3（CO_2-eq） accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH_3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer.
文摘[Objective] This study aimed to investigate the adsorption properties of the adsorption tower filled with calcium superphosphate on ammonia volatilized with aer- ation. [Method] Adsorption tower filled with calcium superphosphate was adopted as experimental apparatus, which was constructed by poly vinyl chloride （PVC） circular tubes. With hartshorn as the source of ammonia volatilization, the effect of different ratios of height to diameter of the tower filled with equal amount of calcium super-phosphate on ammonia adsorption was investigated. In addition, adsorption tower with height-diameter ratio of 9.9 was selected to adsorb the ammonia emitted from the composting systems of pig manure and chicken manure with optimized and reg- ulated carbon-nitrogen ratio. [Result] Under certain volatilization rate, calcium super- phosphate particles in the adsorption tower could effectively adsorb the ammonia, and the adsorption efficiency was enhanced with the increase of height-diameter ra-tio, which could reach above 90% with height-diameter ratio of more than 1.1; the ammonia emitted from composting systems of pig manure and chicken manure with optimized and regulated carbon-nitrogen ratio could be completely absorbed using adsorption tower with height-diameter ratio of 9.9 filled with calcium superphosphate accounting for about 8% of the weight of composting materials. [Conclusion] Experi- mental results of this study provided reference for the application of adsorption tower filled with calcium superphosphate in the treatment of waste gas emitted from com- posting materials.
基金Supported by the National Key Technology Research and Development Program during the 12th Five-Year Plan Period of China(2012BAD14B09)Earmarked Fund for China Agriculture Research System(PXM2013-014207-000096)Beijing Higher Education Young Elite Teacher Project(YETP1714)~~
文摘This study aimed to investigate the bacterial communities in mushroom compost piles composed of rice straw, corn stover, and cow dung. Bacterial com- munities of samples at the beginning of composting, at the end of fermentation phase I and II were collected and analyzed using Polymerase Chain Reaction-De- naturing Gradient Gel Electrophoresis （PCR-DGGE） based on 16S rDNA universal primers from Escherichia coli. A total of 56 different clone sequences were obtained （GenBank accession number： KF630598-KF630653）. They were classified into seven phyla and 42 genera. Dominant microflora during composting belonged to phylum Proteobacteria, Firmicutes, and Actinobacteria, with the dominant genera of Bacillus, Paenibacillus, Thermomonospora, Thermasporomyces, Pseudomonas, and Cellvibrio. Bacterial diversity （Shannon index） analysis showed that bacterial species in com- post pile composed mainly of rice straw continuously increased during composting, while those in compost pile composed mainly of corn stover firstly increased and then reduced. Principal component analysis showed that corn stover compost sam- ples at the end of fermentation phase I and phase II were clustered into one group, suggesting that corn stover composted faster than anticipated. In general, rice straw compost has higher bacterial diversity but longer composting time period, while corn stover compost has lower bacterial diversity but shorter composting time period.
文摘Development of home compostable materials based on bioavailable polymers is of high strategic interest as they ensure a significant reduction of the environmental footprint in many production sectors.In this work,the addition of thermoplastic starch to binary PLA/PBAT blends was studied.The compounds were obtained by a reactive extrusion process by means of a co-rotating twin screw extruder.Thermomechanical,physical and chemical characterization tests were carried out to highlight the effectiveness of the material design strategy.The compounds were subsequently reprocessed by cast extrusion and thermoforming in order to obtain products suitable for the storage of hot food.The extruded films and the thermoformed containers were further characterized to highlight their thermo-mechanical,physical and chemical properties.Thermo-rheological,mechanical and physical properties of the material and of the cast film were analyzed thoroughly using combined technique as capillary rheometer,MFI,DSC,VICAT/HDT,XRD,FTIR,UV-Vis,SEM,permeability and,lastly,running preliminary chemical inertness and biodegradation tests.Particular attention was also devoted to the evaluation of the thermo-mechanical resistance of the thermoformed containers,where the PLA/PBAT/TPS blends proved to be very effective,also presenting a high disintegration rate in ambient conditions.
基金Supported by Ningxia Science and Technology Research Projects"The Carbon Balance Ecological Chicken Technology of Ningxia Desert Research"(KGZ101104)~~
文摘[Objective] In order to study the influence of bacteria and accessories of chicken manure compost.[Method] The experiment was conducted to investigate the changes of temperature,the quantification of Escherichia coli and the odor during chicken manure compost by adding sawdust,rice husk,yeast and lactic acid bacteria respectively.[Result] The results showed that：（1） The yeast group reached the highest fermentation temperature 67.6 ℃,which was 6.9 ℃ higher than that of lactic acid bacteria group,and the fermentation time of yeast group kept over 55 ℃for 16 days,which was 5 days longer than that of lactic acid bacteria group,both of which were better than that of control group（55.9 ℃,5 days）;（2）The highest fermentation temperature of sawdust group was 2.2 ℃ higher than that of rice husk group,and the fermentation time of sawdust group kept over 55 ℃ was 3 days longer than that of rice husk group;（3） The quantification of E.coli reduced from10^5 to 10^2per gram in both of the yeast group and the lactic acid bacteria group.The odor of the yeast group and the lactic acid bacteria group disappeared in the seventh day and the eighth day respectively.[Conclusion] The results showed that the adding of yeast and sawdust was the best condition for chicken manure composting in this experiment.
基金Supported by Agricultural Scientific and Technological Achievement Transformation and Popularization Project of Tianjin(201003010)~~
文摘In order to investigate the influence of secondary classification mode on waste generation features, this study classified domestic waste generated by 310 rural and urban households at urban areas and Shuigaozhuang Village of Xiqing District into 3 groups： compostable materials, recyclable materials and toxics on the basis of the constructed secondary classification mode of domestic waste. The study focused on waste generation strength and classification features, compared the waste generation features between rural and urban residents, and analyzed the re- lation between waste generation strength and economic and cultural factors. The re- sults indicated that the average generation speed of urban domestic waste was 423.08 g/（d.capita）, and that of rural domestic waste was 629.89 g/（d.capita）, there was significant difference between rural and urban compost generation strength （P= 0.00002）, while the generation strength of recyclable materials and toxics between rural and urban areas had no significant difference （P=0.471 and P=0.099, respec- tively）. Secondary classification mode is an effective source classification mode for domestic wastes and has positive effects on waste reduction and treatment.
文摘Polyethylene (PE) films with additives consisting mainly of oleic acid and ferrous ions were subjected to accelerated degradation at simulated composting temperatures.Based on Fourier transform infrared spectroscopy and measurements of mechanical properties and viscosity average molecular weight,the degradation of the films was characterized and the degradation mechanism was discussed.The films containing additives with ferrous ions represent considerable decreases in molecular weight,and the carbonyl groups and hydroperoxides in the aging films show different trends of increase with the aging time.These results indicate that the ferrous ion plays an important role in the degradation of PE films and accelerates the degradation of PE.
文摘The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost environment.The mechanical properties,viscosity average molecular weight (M η) of PE and hydroperoxide (POOH) concentration in the samples were measured.FT IR and DSC were also applied to characterize some samples.It was shown that the above mentioned metallic organic compounds can catalyze the degradation of LDPE efficiently.After 2 months aging,all samples with catalysts became fragile and the M η of the material decreased dramatically.Furthermore,the concentration of carbonyl and the degree of crystallinity of the material increased with the aging time.
基金part of the Sino-German cooperation project of the Recycling of Organic Residues from Agricultural and Municipal Residues in China (http://www.organicresidues.de) and the National Natural Science Foundation of China (No. 40971177)
文摘Gaseous emission （N2O, CH4 and NH3） from composting can be an important source of anthropogenic greenhouse gas and air pollution. A laboratory scale orthogonal experiment was conducted to estimate the effects of C/N ratio, aeration rate and initial moisture content on gaseous emission during the composting of pig faeces from Chinese Ganqinfen system. The results showed that about 23.9% to 45.6% of total organic carbon （TOC） was lost in the form of CO2 and 0.8% to 7.5% of TOC emitted as CH4. Most of the nitrogen was lost in the form of NH3, which account for 9.6% to 32.4% of initial nitrogen. N20 was also an important way of nitrogen losses and 1.5% to 7.3% of initial total nitrogen was lost as it. Statistic analysis showed that the aeration rate is the most important factor which could affect the NH3 （p = 0.0189）, CH4 （p = 0.0113） and N20 （p = 0.0493） emissions significantly. Higher aeration rates reduce the CH4 emission but increase the NH3 and N20 losses. C/N ratio could affect the NH3 （p = 0.0442） and CH4 （p = 0.0246） emissions significantly, but not the N20. Lower C/N ratio caused higher NH3 and CH4 emissions. The initial moisture content can not influence the gaseous emission significantly. Most treatments were matured after 37 days, except a trial with high moisture content and a low C/N ratio.
基金National Natural Science Foundation of China(No.49831070) the ChineseAcademy of Sciences(No.KZ951-B1-207-01-03).
文摘Laboratory simulation studies and composting pilot study wereconducted to evaluate the capacity of three strains of fungi,indigenous fungus Fusarium sp. And Phanerochaete chrysosporium andCoriolus Versicolor, to remediate petroleum-contaminated soils. Inlaboratory, the fungi were inoculated into a liquid Culture mediumand the petroleum-contaminated soil samples for incubation of 40 and50 days, respectively. In the 200-day pilot study, nutrient contentsand moisture were adjusted and maintained under aerobic Condition incomposting units using concrete container (118.5 cm×65.5 cm×12.5cm) designed specially For this study.
基金The study is part of the 1999–2002 research program "Municipal solid waste treatment and compost agriculture application" which is supported jointly by the Tunisian Secretariat of Scientific Research and Technology
文摘The aim of this study was to characterize the biological stability and maturity degree of compost during a controlled pile-composting trial of mixed vegetable residues （VR） collected from markets of Tunis City with residues of Posidonia oceanica （PoR）, collected from Tunis beaches. The accumulation in beaches （as well as their removal） constitutes a serious environmental problem in all Mediterranean countries particularly in Tunisia. Aerobic-thermophilic composting is the most reasonable way to profit highly-valuable content of organic matter in these wastes for agricultural purposes. The physical, chemical, and biological parameters were monitored during composting over 150 d. The most appropriate parameters were selected to establish the maturity degree. The main result of this research was the deduction of the following maturity criterion： （a） C/N ratio 〈 15; （b） NH4^＋-N 〈 400 mg/kg; （c） CO2-C 〈 2000 mg CO2-C/kg; （d） dehydrogenase activity 〈 1 mg TPF/g dry matter; （e） germination index （GI） 〉 80%. These five parameters, considered jointly are indicative of a high maturity degree and thus of a high-quality organic amendment which employed in a rational way, may improve soil fertility and soil quality. The mature compost was relatively rich in N （13.0 g/kg）, P （4.74 g/kg） and MgO （15.80 g/kg）. Thus composting definitively constitutes the most optimal option to exploit these wastes.
