Liquid Cow Manure Research Articles

EFFECT OF LIQUID COW MANURE ON CHEMICAL AND BIOLOGICAL PROPERTIES IN AN ANDISOL

The aim of this work was to establish the effect of the dose of liquid cow manure (LCM) on some chemical properties and biological activity in an Andisol. This study was carried out under laboratory conditions using an Andisol and LCM from a dairy farm located in the South of Chile. The dose of LCM were the equivalent to 0 (S0), 100 (S100), 200, (S200) and 300 (S300) thousand L ha -1 . This amount is equivalent to regular agronomic LCM applications. The chemical characterization indicated that the LCM addition modified all the tested Andisol chemical properties. These begin to return to the initial conditions from 10 days on, with the exception of EC, K and DOC. The C- CO2 evolution indicated that LCM incorporation at increasing dose enhanced the respiratory activity. Enzyme activity was greater in the amended soils than in S0. The results of this study indicated that the period of time necessary for the LCM amended soils returning to a similar behavior to S0 is more than 10 days, with a strong correlation between the chemical properties of the amended soils and their biological activity, mainly C-CO2 evolution.

Biogas production from anaerobic co-digestion of agroindustrial wastewaters under mesophilic conditions in a two-stage process

Abstract Co-digestion of organic wastes is a technology that is increasingly being applied for simultaneous treatment of several solid and liquid organic wastes, in which the content of nutrients can thereby be balanced, and the negative effect of toxic compounds on the digestion process may be decreased giving an increased gas yield from the biomass. Moreover, co-digestion may contribute to a more efficient use of anaerobic digestion (AD) reactors and cost-sharing by processing multiple waste streams in a single facility. In this study, efficient biodegradation of a mixture containing olive mill wastewater (OMW), liquid cow manure (LCM) and cheese whey (CW) using a two-stage anaerobic process was examined. Two continuously stirred tank reactors (CSTRs) were used under mesophilic conditions (35°C) in order to enhance acidogenesis and methanogenesis. The overall process was designed with a hydraulic retention time (HRT) of 19 days. The acidogenic reactor was initially fed with an influent mixture composed of 55% OMW, 40% CW and 5% LCM. After the 87th day of operation, the mixture was changed to 90% of CW and 10% of LCM based on the actual availability of wastes produced by the respective agroindustries. The average removal of dissolved chemical oxygen demand (COD) was 75.5% and 85.2% for the two examined scenarios at OLR of 5.5 ± 0.36 and 4.5 ± 0.30 g total COD/Lreactor/d, while the methane production rate at the steady state reached 1.35 ± 0.11 and 1.33 ± 0.15 L CH 4 /Lreactor/day respectively.

Effect of dairy manure rate and the stabilization time of amended soils on atrazine degradation

The application rate of liquid cow manure (LCM) in the field and the stabilization time of amended soils before application of pre-plant herbicides are factors that determine their efficiency. This study includes evaluation of residual atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) in soil and amended soils with equivalent rate of 100,000; 200,000; and 300,000 L ha −1 of LCM and the effect of pre-incubation time of amended soils on atrazine degradation. The study was carried out under controlled conditions using an Andisol with previous historical application of atrazine. The respiratory activity and fluorescein diacetate (FDA) studies indicated that the time necessary for stabilization of amended soils is over 20–30 d. During the measurement of respiratory and FDA activity, no significant differences were observed when atrazine was applied. The half-life of atrazine ranged from 5 to 8 d and the relative distribution of degradation products seem to be affected by the application of LCM. The pre-incubation time of amended soil and LCM dose would not affect atrazine degradation rate, when the soil has a history of herbicide application. However, repeated applications of LCM in a long period of time could change the soil pH and increase the content of dissolved organic carbon (DOC) which could further contribute to a faster degradation of atrazine. Both effects would reduce the effectiveness of atrazine in weed control.

Effect of Liquid Cow Manure on Andisol Properties and Atrazine Adsorption

Application of animal manure amendments to agricultural soils is a common practice to improve soil fertility through the addition of essential plant nutrients. This practice may increase the potential for atrazine (2-chloro-4-ethylamino-6-isopropylamino-1, 3, 5-triazine) leaching due to competition for adsorption sites between the pesticide and dissolved organic carbon (DOC) added through manure. We evaluated the influence of liquid cow manure (LCM) application on soil properties, atrazine adsorption, and the physicochemical controlling mechanisms in an Andisol. The LCM was applied at rates equivalent to 0, 100,000, 200,000, and 300,000 L ha(-1), resulting in treatments S-0, S-100, S-200, and S-300, respectively. The LCM application increased DOC and pH of the soils immediately on addition, but pH returned to S-0 values 30 d after application. The LCM application did not modify atrazine adsorption with the two lowest application rates (S-100 and S-200), but atrazine adsorption was decreased in S-300 (K(f) = 0.96) compared with the control (S-0) (K(f) = 1.19), possibly due to the competitive adsorption of DOC with the pesticide. The Fourier-transformed infrared analysis showed that LCM increased aliphaticity and presence of N-containing groups and polysaccharide-like groups in amended soils; however, these properties did not modify the atrazine interaction in the studied amended soils. Interestingly the addition of DOC to soil at the high application rate (S-300) reduced atrazine adsorption in this rich OM Andisol despite the LCM not raising the concentration of stable organic matter. The application of high rates of liquid manure containing DOC incurs an increased risk of pesticide leaching.

Design of A Solar Thermophilic Anaerobic Reactor for Small Farms

A 10 m 3 completely stirred tank reactor has been designed for anaerobic treatment of liquid cow manure under thermophilic conditions (50°C), using a solar heating system mounted on the reactor roof. Simulation models for two systems have been developed. The first system consists of loose components and in the second system the components are integrated. Each of the two systems includes a heat recovery unit to heat the influent by extracting heat from the effluent. The integrated system includes an extra chamber for the pumps and the heat recovery unit, which are in the same insulating cover as the reactor and the solar collector. The control system is based on simple on/off strategy. An auxiliary heater, operated with the produced biogas, can be used during cold months. The measured and calculated design parameters are presented. The simulation results show that the temperature fluctuation of the reactor during the night is less than 1°C, which is too small to harm the microbial activity. The results show that an annual net thermal energy production and overall annual energy efficiency of 100 and 95%, respectively, could be obtained from the integrated system.

Behaviour and Impact of Cow Slurry Beneath a Storage Lagoon: 1. Groundwater Contamination 1975–1982

The chemical and biological composition of groundwater sampled from a 76 m deep borehole situated 80 m from an unlined, earth-banked lagoon excavated in Upper Chalk and continuously used to store liquid cow manure was regularly monitored from August 1975 to January 1982 for signs of pollution. The lagoon became self-sealing 3 months after the start of filling in 1975, but was further enlarged and re-filled in autumn 1976, and emptied by dragline in September 1978 and 1980. No significant changes in groundwater composition were detected in the period August 1975 to December 1978. In January 1979, significant numbers of Escherichia coli and a large, rapid increase in concentrations of ammonium-nitrogen (NH4-N), phosphorus (P), potassium (K), sodium (Na), chloride (Cl) and sulphate (SO4) were detected in the groundwater. Nutrient concentrations fluctuated at elevated levels throughout 1979 but decreased during 1980. Additional bacterial and chemical (NH4-N, P and K) contamination was recorded in January 1981 and subsequent months. The contamination was considered to have occurred as a result of fissure flow through the unsaturated zone of the Upper Chalk following repeated disruption of the self-sealing layer during emptying of the lagoon by dragline in September 1978 and 1980. The results indicate that unlined, earth-banked slurry storage lagoons need to be carefully managed to avoid biological and chemical pollution of Chalk aquifers.

Accelerated Test of Paper Mulch Degradation

In 1994, field trials were undertaken to evaluate the agronomic performance of a range of paper mulches in vegetable production. During the course of the experiments, the majority of the paper mulches tested degraded part way through the growing season. Before the next growing season, a range of Kraft papers differing in densities and compositions were subjected to an accelerated degradation test to determine which mulches would be suitable for use under Quebec field conditions. A mixture of equal parts black soil, sand, and manure (two parts sheep manure and one part liquid cow manure) was placed into trays of 26 x 52 cm. Experimental papers were cut into strips measuring 2.5 x l.5 cm and put into the trays such that half of the strips were covered with the mixture. The trays were placed in a growth cabinet (30C with a relative humidity of 50%). Three replicates of each treatment were sampled 3, 5, 7, 11, and 14 days after placement to determined the amount of degradation that had taken place. It was found that the length of time taken for degradation in the accelerated system was 3.7 times less than that of the field.

Intensive polyculture of fish in freshwater ponds. I. Substitution of expensive feeds by liquid cow manure

In 1974 and 1975 nine experimental treatments of fish polyculture in stagnant water ponds without aeration were conducted at Dor. The polyculture was composed of common carp, silver carp, white amur (grass carp) and Tilapia. The treatments differed in stocking densities, feeding and manuring levels. The most productive treatment of the experiment, in which the fish were fed with protein-rich pellets, produced 50 kg/ha per day, probably a record for unaerated ponds of stagnant water. Two treatments (low and high stocking densities) fed exclusively with liquid cow manure produced an average yield of around 32 kg/ha per day. The yields of the treatments receiving high-protein pellets exceeded those of the treatments receiving grain pellets by 20 and 9.6 kg/day per ha, at high and low stocking densities, respectively, and in both cases the yield increments justified the extra cost of high-protein feed. The responses of the four fish species to the different levels of feeding and stocking densities were widely different. The common carp and white amur showed the greatest responses to increased feeding inputs while the silver carp and Tilapia, even at high densities, have done equally well at low feeding levels. Total body fat contents of the common carp were 20%, 15% and 6.2% when fed with high-protein pellets, grains pellets and liquid cow manure, respectively. Intermittent harvesting did not result in increased yields.