Production of Biogas from Olive Mill Waste Waters Treated by Cow Manure

The olive mill waste waters (OMWW) generated from olive oil extraction is a major environmental concern since they are characterized by their role as a pollutant (high organic and mineral matters) and their pH acid. The aim of this study was to valorize (OMWW) by anaerobic fermentation in the presence of cow manure in order to produce biogas and reduce their toxic load. Many tests were carried out by fermenting (OMWW) with polyphenols in the presence of cow manure in thermophile temperatures. The performance of this treatment was valuated through measurements of biogas production and by the determination of different parameters of fermented media (pH, volume of the biogas and polyphenols).

Cow manure and cow manure-derived biochar application as a soil amendment for reducing cadmium availability and accumulation by Brassica chinensis L. in acidic red soil

Organic amendment is a promising,in situ phytostabilization approach to alleviate the phytotoxic effects of heavy metal contaminated soils.The aim of this study was to evaluate the feasibility of cow manure（CM）and its derived biochar（CMB）as a soil amendment on cadmium（Cd）availability and accumulation in low and high Cd-accumulating cultivars of Brassica chinensis L.grown in an acidic red soil.CM and CMB were applied to Cd-contaminated acidic red soil at the rates of 0,3.0and 6.0%（w/w）.Application of CMB was significantly more effective than that of CM,as it reduced the availability of Cd in soil by 34.3–69.9%and its bioaccumulation in the low Cd accumulator,Aijiaoheiye 333,by 51.2 and 67.4%,respectively.The addition of CMB significantly increased the extractability and accumulation of trace metals（Zn,Mn,Fe,and Cu）by plants and improved plant biomass production.CMB application,combined with utilizing low Cd accumulating cultivars represents a new,sustainable strategy to alleviate the toxic effects on Cd and improve food safety.

Effects of Different Microbial Agents on Aerobic Composting of Cow Manure

For the control of environment pollution caused by livestock and poultry manure, four microbial strains conducive to aerobic composting were selected and mixed into four compound microbial agents, and effects of different compound microbial agents on aerobic composting of cow manure were studied from aspects of changes in temperature, pH, water content and C/N during the composting process. The results show that microbial agent M2 has the best effect for aerobic composting of cow manure, so microbial agent M2 has broad popularization and application prospect in livestock and poultry farms in low-temperature areas of Northeast China.

Biohydrogen Production from Synthetic Waste Co-digested with Liquid Dairy Cow Manure： Effect of Temperature and Mixing Ratio

Biohydrogen production from synthetic waste, SW （model organic fraction of municipal solid waste） co-digested with liquid dairy manure （M） was tested in batch reactions to assess the effect of temperature and mixing ratio of the substrates. A 5 × 2 factorial design experiment was conducted. Synthetic waste： manure mixtures of 1：1, 2：1, 3：1, 1：0, 0：1 （volatile solids, VS, basis） were tested at 37 （T37） and 55 ℃ （T55） using thirty 1 L laboratory scale digesters. Total VS of each mixture was 50 g/L except SW：M 0：I treatment, where total VS was 27.4 g/L. Gas samples were taken daily to determine hydrogen production, and slurry samples taken before and after experimentation, were analyzed for volatile fatty acid （VFA） concentration, volatile solid （VS） degradation, ammonium nitrogen （NH4＋-N） and pH. Hydrogen production （mL/g-VS fed） showed a significant two-factor interaction between incubation temperature and SW：M ratio （P 〈 0.001）. Maximum production of 15.8 mL/g-VS （fed） was achieved in SW：M ratio of 3：1 at 55 ℃. Generally, hydrogen productions at thermophilic temperature （T55） were significantly higher than at mesophilic （T37） temperature for all treatments （P 〈 0.001） except for SW：M 1：0 and SW：M 0：1 treatments （P 〉 0.05）. This study indicates that hydrogen production from co-digestion of synthetic waste and manure is dependent on incubation temperature and relative contribution of wastes in the mixture.

Application of Cow Manure Combined with Rice Husk Ash to Increase Soybean (Glycine max (L.) Merr) Production in Indonesia Ultisol

This study aims to determine the ability of CM(Cow Manure)combined with RHA(Rice Husk Ash)to provide a significant effect on the growth and production of soybean planted in an ultisol.It was conducted in a pot experiment at the Experimental Site of the Faculty of Agriculture,Sriwijaya University,Indralaya,Indonesia between September 2019 and February 2020 using completely randomized design factorial with two factors which were two rate levels of RHA at 3.75 and 7.5 tons·ha^(-1) and three rate levels of CM at 0,10,and 20 tons·ha^(-1).It is important to note that each combination was repeated three times,thereby,leading to a total of 18 pots.The variables studied were plant growth and yield which are represented by plant height,the total number of pods,number of filled pods,seed weight per plant,and soybean produced.The results showed that CM combined with RHA was effective in increasing nutrient availability and reducing soil acidity.It was discovered that CM had a significant effect on soil pH,plant height,the total number of pods,number of filled pods,seed weight per plant,and soybean produced while RHA did not have any significant difference on all the variables observed.However,the combination of 10 tons·ha-1 CM with 3.75 tons·ha-1 RHA was observed to be the best combination treatment to increase the growth and production of soybean in ultisol as indicated by its ability to produce 2.58 tons·ha^(-1) soybean.

The Influence of Cow Manure and Mycorrhiza Application in Oil Palm(Elaeis guineensis Jacq.)Growth on Pre Nursery

The objective of this study was to know the influence of cow manure and mycorrhiza dosages on growth of oil palm seedling in pre nursery.This study has been done in INSTIPER(Educational and Research Garden in Stiper Agricultural Institute)at Maguwoharjo,Depok,Sleman,Yogyakarta,Indonesia in March until December 2021.The experimental design used was Completely Randomized Design with two factors.The first factor was 4 dosages of cow manures with volume comparison of subsoil:C1(30% of cow manure),C2(40% of cow manure),C3(50% of cow manure).The second factor was 3 dosages of mycorrhiza consist of M0(no mycorrhiza),M1(10 g mycorrhiza)and M2(20 g mycorrhiza).The study used five replications.Data were analyzed by ANOVA(Analysis of Variance)followed by DMRT(Duncan Multiple Range Test)at 5% significant level.The result showed no significant interaction between cow manure and mycorrhiza dosages application.Mycorrhiza significantly influenced plant height,sum of leaves,stem diameter,crown dry weight and root dry weight.Mycorrhiza on 20 g was the best.

Enhancement of biogas potential of primary sludge by co-digestion with cow manure and brewery sludge

Anaerobic digestion(AD)has long been used to treat different types of organic wastes especially in the developed world.However,organic wastes are still more often considered as a waste instead of a resource in the developing world,which contributes to environmental pollution arising from their disposal.This study has been conducted at Bugolobi Sewage Treatment Plant(BSTP),where two organic wastes,cow manure and brewery sludge were co-digested with primary sludge in different proportions.This study was done in lab-scale reactors at mesophilic temperature and sludge retention time of 20 d.The main objective was to evaluate the biodegradability of primary sludge generated at BSTP,Kampala,Uganda and enhance its ability of biogas production.When the brewery sludge was added to primary STP sludge at all proportions,the biogas production rate increased by a factor of 3.This was significantly(p<0.001)higher than observed gas yield(337±18)mL/(L·d))in the control treatment containing(only STP sludge).Co-digesting STP sludge with cow manure did not show different results compared to the control treatment.In conclusion,Bugolobi STP sludge is poorly anaerobically degradable with low biogas production but co-digestion with brewery sludge enhanced the biogas production rate,while co-digestion with cow manure was not beneficial.

Effects of cow manure ratios on methane production and microbial community evolution in anaerobic co-digestion with different crop wastes

The present study investigated the effects of cow manure ratios mixed with maize stover,rice straw,and wheat stalk at 3,2,1(total solid based,TS-based),respectively,on methane production and microbial community structure during the anaerobic co-digestion process.Results showed cow manure co-digested with maize stover,wheat stalk,and rice straw at ratios of 2,1,and 3 had the highest cumulative methane yields(272.99,153.22167.73 mL/g volatile solid(VS),respectively)and better stability(e.g.pH,volatile fatty acids(VFAs)and their component).The main microbe evolution had a similar trend which was Petrimonas and Methanosaeta in the early digestion process(Days 0-7)and then evolved into Longilinea,Ruminofilibacter,and Methanosarcina with the progress of digestion,but the relative abundance of these microbes in each reactor was different.It was worth noting that Caldicoprobacter in cow manure to maize stover ratio of 2,and to rice straw ratio of three reactors had a relatively higher proportion than reactor of cow manure to wheat stalk ratio of 1,and Hydrogenophaga was the specific bacterium in cow manure to wheat stalk ratio of 1 reactor.In addition,Petrimonas showed positive relationship with VFAs and Longilinea was the opposite.Methanosaeta and Methanobacterium contributed the most during the peak period of methane production in cow manure and maize stover co-digested reactor,and showed positive relationship with acetic acid.However,Methanosarcina and Methanospirillum made a great contribution during the peak period of methane production in cow manure co-digested with wheat stalk and rice straw reactors.These findings could provide further information on the application of cow manure co-digested with crop wastes.

Water extractable plant nutrients in soils amended with cow manure co-composted with maple tree residues

Studies on the availability of plant nutrients in soils treated with manure co-composted feed-stocks are very rare.The present investigation aimed at studying the nutrient release pattern from three soils amended with maple tree leaves co-composted with cow manure.Soils were mixed with the compost at the rate of 20 t/hm^(2) and incubated at room temperature.Prior to incubation,plants residue samples were analyzed for total elemental concentrations(NO_(3),NH_(4),P,K,Ca,Mg,Na,Zn,Mn,Fe,Cu,Ni and Cd).Water extractability of nutrients from soils was affected by the type of soil and ratio of composted manure applied.Extractable NH_(4),P,K,Ca and Mg concentrations varied in the descending order of sandy clay,sandy loam and silt loam except NO_(3).The concentrations of P,K,Ca and Mg in the amended soils increased with the ratio of manure co-composted with leaf litter while those of NO_(3),NH_(4) and trace elements decreased.The residual nutrients in soil varied directly with their contents in the compost amendments.Co-composting improved the availability of nutrients in soils and this should be an ideal approach to managing the enormous waste generated from the livestock sector for restoring soil fertility.

Changes in Soil Physicochemical Properties under Selected Climate-Smart Agricultural Practices in Central African Republic

Soil nutrient depletion as a result of continuous cultivation with insufficient external nutrient replenishment is a major challenge in sub-Saharan Africa (SSA). A trial using the organic and mineral fertilizer was established in the cassava cropping system of the Pissa and Damara areas to address the declining soil fertility. The study aimed to evaluate the effect of cow manure and mineral fertilizer in combination or sole application on soil physico-chemical properties and macronutrients. The experimental trial adopted a randomized complete block design (RCBD) replicated four times. The treatments comprised of;T1 (Control), T2 (Peasant practice), T3 (sole NPK), and T4 (Cow manure + NPK). The data on soil physicochemical analysis was subjected to a one-way analysis of variance in SAS 9.4 and the mean was separated by Tukey’s HSD test at p < 0.005. The soil pH values ranged from 4.20 to 4.91;and 4.53 to 5.28 in Pissa and Damara respectively. According to the treatments, a low pH value is observed in T3 (4.13) in the Pissa. Combined use of cow manure and the mineral fertilizer resulted in higher Mg K and N in the Pissa region and higher soil pH in Damara. The use of sole NPK (T3) gave a higher soil carbon and CN ratio. In the Pissa region the CEC, Cu, Fe, and Zn were higher in the treatments with mineral fertilizer compared to the control. Conclusively, the use of mineral fertilizer and cow manure can be used with optimum rates to improve soil physico-chemical properties on a sustainable basis.

Study on the Activation Effect of Fermented Organic Fertilizers on Selenium in the Soil of Southern Dragon Fruit Orchards

[Objectives]This study was conducted to explore the effects of using fermented organic fertilizers such as cow manure on the activity of selenium in the soil.[Methods]The project team applied the organic fertilizer prepared by fermenting cow manure and other raw materials to activate selenium in the soil at two dragon fruit orchard bases in Shilong Town,Guiping City and Dingdang Town,Long an County,and carried out many years of experiments.[Results]The contents of available selenium in the two experimental orchards in Shilong Town and Dingdang Town increased by 10%and 5%,respectively,and the selenium contents in dragon fruit increased by 228.6%and 200.0%,respectively.[Conclusions]The application of fermented organic fertilizers such as cow manure can increase available selenium content in the soil,thereby increasing the selenium content of dragon fruit.