Assessment of selected surfactants for enhancing C mineralization of an oily waste

A laboratory incubation experiment to assess (a) the effectiveness of six surfactants as emulsifiers in enhancing oily waste carbon mineralization rates (CMR), (b) the influence of ion charge of the surfactants on CMR, and (c) the biodegradation of the surfactants in soil, is described. The CMR and the net cumulative C mineralization (CCM) data indicated that among the six surfactants evaluated two were significantly effective in enhancing CMR through emulsification. They were CEDEPHOS FA-600, an anionic surfactant mixture of mono- and di- organo phosphate esters and IGEPAL CO-603, a nonionic ethoxylated alkylphenol.     

Effect of organic residue amendment on mineralization of sulfur in flooded rice soils under laboratory conditions

Abstract

This study was undertaken to assess the mineralization of sulfur (S) in laboratory conditions of three rice soils (Joydebpur, Faridpur, and Thakurgaon), receiving the following treatments: 1) control, 2) rice straw (Oryza sativa L.), and 3) pea vine (Pisum sativum L.). The organic residue (25 mg g^‐1) was added and mixed with soil and glass beads (1:1, soil to bead ratio) and placed into a Pyrex leaching tube. The soils were flooded and incubated at 35°C, after which they were leached with deionized water at 1, 2,4, 8, and 12 weeks for analysis of SO₄ and other chemical properties in the leachates. Potentially mineralizable S (S_o) and C (C_o) pools and first‐order rate constants (K_s for S and K_c for C) in soils amended with rice straw and pea vine under flooded conditions were estimated using an exponential equation. The S_o and K_s varied considerably among the soils and types of added organic residues, and their values in rice straw and pea vine ranged from 8.70 to 29.55 and 0.124 to 0.732 mg S kg^‐1 wk^‐1, respectively. Except for the Thakurgaon soil, the S_o and K_s values in Joydebpur and Faridpur soils were higher in the unamended treatments. Higher S_o values in the unamended soils were probably due to less microbial activity to mineralize organic S from organic residues. The results indicate that the amount of SO₄ in flooded soils amended with organic residues are dependent on soil type, nature of organic residues, and time of incubation. The C_o and K_c values under flooded incubation were higher in residue amended soils than in unamended soils. Pea vine treated soils had higher C_o and K_c values than the soils treated with rice straw.     

Biodegradation of an oily waste as influenced by nitrogen forms and sources

Biodegradation rates of oily waste in soil can be limited by mineral nutrients, particularly N and P. A laboratory incubation experiment was carried out to investigate the influence of N forms, nitrate (NO^? ₃-N) vs ammonium nitrogen (NH⁺ ₄-N), and sources, i.e., the conjugate cations/anions, on C mineralization rate (CMR) was determined daily by measuring the CO₂ evolved using gas chromatography. The CMR and the cumulative C mineralized (CCM) varied with the form and/or the source of N applied. The greatest enhancement in CMR occurred in the NO^? ₃-treatments in which the source conjugate cation was Ca⁺². The addition of P fertilizer further enhanced C mineralization rates irrespective of the form and/or the source of N added. The results show that up to 45% of the added oily waste mineralized as CO₂-C in 28 d. The residual P and N (NO^? ₃-N plus NH⁺ ₄-N) data showed that approximately 90% of the added P and N were utilized for oil decomposition. The amount of residual NO^? ₃-N appeared to have an inverse relationship with CCM. The NO^? ₃-N utilization occurred at the expense of NH⁺ ₄-N and this was particularly high in the treatments which received P.     

Effect of organic residue amendment on mineralization of nitrogen in flooded rice soils under laboratory conditions

Abstract

This study was undertaken to assess the mineralization of nitrogen (N) in rice soils amended with organic residues under flooded condition. A lab incubation study with a 3x3 factorial design (two replications) was conducted with three rice soils (Joydebpur, Faridpur, and Thakurgaon) receiving the following treatments: 1) control, 2) rice straw (Oryza sativa L.), or 3) pea vine (Pisum sativum L.). The organic residue (25 mg straw g^‐1 soil) was mixed with soil and glass beads (1:1, soil to beads ratio), and transferred into a Pyrex leaching tube, flooded and then incubated at 35°C for up to 12 weeks. The soils in the leaching tubes were leached (while maintaining flooded condition) at 1,2,4, 8, and 12 weeks with deionized water for determination of NH₄‐N, NO₃‐N, pH, and Eh. Nitrogen mineralization in soils amended with rice straw was somewhat different than that of soils treated with pea vine. Soil treated with rice straw had a higher N mineralization rate than soils treated with pea vine, which was due to a lower carbon (C):N ratio for rice straw. The potentially mineralizable N pool (N_o) in soils amended with rice straw and pea vine under flooded conditions, estimated using a 1st order exponential equation, were 7 to 15 times, and 3 to 9 times greater for rice straw N_o values and pea vine, respectively, than the control. The K_N values for unamended soils ranged from 0.35 to 0.52 mg N kg^‐1 wk^‐1 and rice straw and pea vine treated soils were from 0.75 to 1.22 and 0.46 to 0.58 mgN kg^‐1 wk^‐1. The lower N_o and K_N values in pea vine treatments suggested there was greater immobilization of N than in rice straw treatments.     

Effect of lignite amendment on carbon and nitrogen mineralization from raw and composted manure during incubation with soil

The application of animal manure as a source of plant nutrients requires the determination of the amount and pattern of nutrient mineralization from manure.A laboratory incubation study was conducted to investigate the influence of lignite amendment and lignite type on carbon(C) and nitrogen(N)mineralization in raw(feedstock) and composted cattle manure following application to soil at 30 and 60 t ha^-1.The mineralization of C and N was determined by measuring changes in CO2 evolution ...     

Influence of municipal waste compost amendment on soil water and evaporation

Abstract

Municipal Waste Compost was added to soils in the glasshouse and field to assess its impact upon soil physical properties. Application was by mulch and incorporation, and the amelioration of temperature, soil water content, unsaturated hydraulic conductivity, and evaporation were investigated. Incorporation in the glasshouse pot experiments increased early season evaporation, while compost applied by either means raised soil temperature. In later stages of drying, the presence of compost reduced the evaporation rate. In the field, compost addition to trials of maize (Zea mays van Melody) improved retention of soil water during a normally wet summer, but not during a very dry summer. Furthermore, soil temperature tended to be reduced by mulching. It is concluded that compost application is beneficial to soil water retention and its subsequent utilization by a crop in conditions of normal rainfall under a temperate climate. Furthermore, it is concluded that the common practice of extrapolating glasshouse‐derived information to field conditions creates serious problems, at least in soil physical experimentation.     

Tillage and amendment effects on soil carbon and nitrogen mineralization and phosphorus release

The influence of tillage and nutrient amendment management on nutrient cycling processes in soil have substantial implications for environmentally sound practices regarding their use. The effects of 2 years of tillage and soil amendment regimes on the concentrations of soil organic matter variables (carbon (C), nitrogen (N) and phosphorus (P)) and C and N mineralization and P release were determined for a Dothan fine-sandy loam soil in southeastern Alabama. Tillage systems investigated were strip (or conservation) and conventional tillage with various soil nutrient amendments that included no amendment, mineral fertilizer, and poultry waste (broiler litter). Surface soil (0–10 cm depth increment) organic matter variables were determined for all tillage/amendment combinations. Carbon and N mineralization and P release were determined on surface soils for each field treatment combination in a long-term laboratory incubation. Soil organic P concentration was 60% greater in soils that had been conventionally tilled, as compared with strip-tilled, both prior to and following laboratory incubation. Carbon and N mineralization results reflected the effects of prior tillage amendment regime, where soils maintained under strip-till/broiler litter mineralized the greatest amount of C and N. Determination of relative N mineralization indicated that strip tillage had promoted a more readily mineralizable pool of N (6.1%) than with conventional till (4.2%); broiler litter amendments had a larger labile N fraction (6.7%) than was found in soils receiving either mineral fertilizer (4.1%) or no amendment (4.7%). Tillage also affected P release measured during the incubation study, where approximately 20% more inorganic P was released from strip-tilled soils than from those maintained under conventional tillage. Greater P release was observed for amended soils as compared with soils where no amendment was applied. Results from this study indicate that relatively short-term tillage and amendment management can significantly impact C, N, and P transformations and transfers within soil organic matter of a southeastern US soil.     

Bioavailability of stabilized oily waste organics in ultrasonified soil aggregates

Stabilization of oily waste organics (OWO) in soils of land treatment farms (LTF) can limit the availability of the OWO for biodegradation. The effect of physical dispersion on bioavailability and biodegradation of OWO in a soil from a LTF was investigated. Soil samples from the LTF were ultrasonically dispersed at increasing energy levels (EL), ranging from 0 to 30 kJ kg^?1 at 5 kJ kg^?1 increments, and incubated in glass jars for 12 weeks. The headspace CO₂ concentration in the jars was monitored weekly by gas chromatography and expressed as C mineralization rates (CMR). The CMR and the cumulative C mineralized (CCM) increased with increasing EL. The CCM from the oily waste treated soil dispersed at 30 kJ kg^?1 was 710% higher compared to that from the untreated soil dispersed at the same EL. Compared to the treated soil dispersed at zero EL, 48% more C mineralized from that dispersed at 30 kJ kg^?1. The size of the potentially mineralizable C (C₀) increased with increasing EL. The C₀ for the treated soil dispersed at 30 kJ kg^?1 was 66% larger compared to that at zero EL. The C₀'s for the treated soil dispersed at different EL were similar, suggesting the chemistry of the C₀ exposed by dispersion were similar. The results show that substantial amounts of potentially biodegradable OWO were physically protected in soil aggregates.     

蘑菇培养废料的土壤培肥增产效果研究

蘑菇培养后的废料做水稻基肥 1～4t/亩 ,可增加土壤有机质 ,有效磷和有效钾 ;提高水稻产量 .     

Management of N mineralization from crop residues of high N content using amendment materials of varying quality

Abstract. A potential technique for reducing overwinter leaching from high N containing crop residues is to immobilize the N released during decomposition by co-incorporating materials of a wider C : N ratio. This article describes the use of laboratory incubation experiments to investigate the effects of a wide range of such amendment materials on the mineralization of N from sugar beet and brassica leaf residues in a sandy loam and a silt loam. These materials were of varying quality, with C : N ratio ranging from 15 : 1 to 520 : 1, and cellulose content from 0 to 34%. Amendments were added at a fixed rate of 3.5 mg C g⁻¹ of dry soil, equivalent to around 10 t ha⁻¹ C (to 20 cm depth). The soils were then incubated at 15°C, and net mineral N derived from the leaves was measured at regular intervals over 168 days. Net mineralization of residue N was greatest with molasses (C : N ratio of 18 : 1), whereas paper waste (C : N ratio of 520 : 1) reduced N mineralized by up to 90% compared with a soil-only control. As the concentration of cellulose and lignin in the amendment materials increased, so the amounts of N mineralized decreased, with 62 and 54% of variance in N mineralized explained by cellulose and lignin content, respectively. Reduced levels of mineral N were associated with higher levels of biomass-N. The levels of N₂O-N lost from sugar beet residues on day 14 were significantly reduced from 66 to 5 g ha⁻¹ where compactor (cardboard) waste had been mixed into sandy loam, but this effect was not observed in the silt loam. These techniques could lead to greater efficiency of N use in rotations through reduction in N losses, and provide alternative routes for disposal of wastes when the EC Landfill Directive is implemented.     

无机氮与蔬菜废弃物耦合对土壤氮矿化的影响

为探明有机废弃物添加量与不同无机氮水平耦合对土壤氮矿化的影响,设计了3个甘蓝废弃叶添加量[B1:200 g.kg 1(土),B2:400 g.kg 1(土),B3:550 g.kg 1(土)]和4个无机氮水平[N0:0 mg.kg 1(土),N1:25mg.kg 1(土),N2:50 mg.kg 1(土),N3:100 mg.kg 1(土)]交互的控制培养试验(25℃,65%的田间持水量)。试验结果显示:各氮处理下土壤净累积氮矿化量是空白对照的4～5倍,N1水平下土壤净累积氮矿化量显著高于其他氮水平。各甘蓝废弃叶添加量处理下土壤净累积氮矿化量是空白对照的3～5倍,且B2添加量下土壤净累积氮矿化量显著高于B1和B3。统计分析表明,氮处理和甘蓝废弃叶添加量之间的交互效应不显著(P=0.275),甘蓝废弃叶的添加是影响氮矿化的主要因素(Eta2=0.16),而供氮水平为次要因素(Eta2=0.07)。B1添加量下,培养前期(0～20 d)土壤净累积矿化量逐渐升高,后期保持稳定水平;但B2和B3添加量下,培养前期(30 d)土壤呈现矿化、固持、再矿化现象,后期土壤净累积矿化量逐渐升高。氮矿化速率结果说明,甘蓝废弃叶添加后氮素矿化主要发生在培养前30 d。对培养期间土壤净累积氮矿化量随时间变化做一级动力方程模拟,拟合效果良好(R2=0.62～0.89)。     

Nitrogen mineralization of silk waste applied to soil under aerobic conditions

Silk waste which is a byproduct of silk reeling consists mainly of silk proteins such as sericin and fibroin. Although silk waste has a high N content (164 g kg^-1) and low CjN ratio (2.16), net N mineralization in soil at 30°C under aerobic conditions was very slow (21.4% in 184 d). The N mineralization rate of silk waste applied to soil after hydrolysis with HCI was higher than that of untreated silk waste. The effect of hydrolysis with 0.2 M HCI for 60 min at 97°C on the net N mineralization for 56 d was twice as high as that with 1 M HCI for 60 min at 97°C. Molecular mass distribution of silk proteins shifted to the lower range by hydrolysis, whose effect with 1 M HCI was more pronounced than that with 0.2 M HCI. The content of the crystal region in silk protein was estimated to be approximately 45% based on the relationship between the reaction (acid hydrolysis) time and the weight of insoluble residues. X-ray diffraction patterns of these residues showed that the crystal structure persisted until at least 180 min after hydrolysis with 1 M HCI at 97°C. These results suggest that crystal regions and the scattered distribution in silk proteins inhibit the decomposition of silk waste in soil. Silk waste could thus be utilized as slow-release fertilizer.     

Effects of municipal solid waste compost and sewage sludge on mineralization of soil organic matter

This work sets out to verify whether the application of municipal solid waste compost (MSWC) or treated urban sewage sludge (USS) organic amendments efficiently promote organic matter (OM) increases in a Haplic Podzol (PZha) and in a Calcic Vertisol (VRcc). For that purpose, carbon (C) mineralization and C kinetic parameters were studied, using a laboratory experimental incubation setup. The results showed that the addition of the amendments to the soils increased their mineralization capacities, and that the highest C mineralization rate was reached at the end of the first 2 d of incubation. The different characteristics of the soils seem to have influenced the C mineralization rates during the 28-d incubation. The USS induced higher C mineralization than the MSWC, and the PZha soil gave rise to higher C mineralization than VRcc. For all treatments, C mineralization adjusted well to an exponential plus linear kinetic model, suggesting that the organic C of the amendments was made up of two organic pools of differing degrees of stability. With the exception of the application of USS 60 t ha⁻¹, all the treatments increased the OM content on both soils, or at least the OM remained constant throughout the incubation.     

Effect of composted sewage sludge amendment on soil nitrogen and phosphorus availability

Abstract

Municipal sewage sludge previously composted with sawdust (CSS) was applied to an eutric sandy cambisol at rates of 7.5, 15.0, 22.5, and 30 g#lbkg^‐1. Incubation and pot experiments were conducted to evaluate CSS effectiveness on nitrogen (N) and phosphorus (P) soil availability and on plant nutrition. The CSS rates did not increase soil mineral N and had little effect on organic P and on labile forms of P. Efficiency of total applied P was 17% for the soil labile forms and 4.8% for the resin extractable fraction. In contrast, CSS significantly increased hydroxide extractable inorganic P and nonextractable soil P fraction. The major portion of the increment on nonextractable forms was at the expense of HC1 extractable P fraction [calcium (Ca)‐bounded], dominant on the original CSS. Thus, chemical rather than biological reactions lead to the redistribution of CSS‐borne P to more firmly held forms after its application to the soil. Ryegrass dry matter yield, N content, and N uptake did not increase in CSS‐treated soils. Plant P content increased at the second harvest, but the effect was nil in the subsequent harvest. Total P uptake increased from 14.1 to 20.2 mg#lbpot^‐1, but percentage P recovery by ryegrass was modest, averaging 2.5% of the CSS‐borne P. Results suggest that moderate application of CSS to agricultural systems are inadequate for crop growth but may contribute to nutrient recycling without environmental risks related to N and P loss.     

Effect of freeze-thaw events on mineralization of soil nitrogen

Summary In humid regions of the United States there is considerable interest in the use of late spring (April–June) soil NO ₃ ^– concentrations to estimate fertilizer N requirements. However, little information is available on the environmental factors that influence soil NO ₃ ^– concentrations in late winter/early spring. The influence of freeze-thaw treatments on N mineralization was studied on several central Iowa soils. The soils were subjected to temperatures of-20°C or 5°C for 1 week followed by 0–20 days of incubation at various temperatures. The release of soluble ninhydrin-reactive N, the N mineralization rate, and net N mineralization (mineral N flush) were observed. The freeze-thaw treatment resulted in a significant increase in the N mineralization rate and mineral N flush. The N mineralization rate in the freeze-thaw treated soils remained higher than in non-frozen soils for 3–6 days when thawed soils were incubated at 25°C and for up to 20 days in thawed soils incubated at 5°C. The freeze-thaw treatments resulted in a significant release of ninhydrin-reactive N. These values were closely correlated with the mineral N flush (r ²=0.84). The release of ninhydrin-reactive N was more closely correlated with biomass N (r ²=0.80) than total N (r ²=0.65). Our results suggest that freeze-thaw events in soil disrupt microbial tissues in a similar way to drying and re-wetting or chloroform fumigation. Thus the level of mineral N released was directly related to the soil microbial biomass. We conclude that net N mineralization following a spring thaw may provide a significant portion of the total NO ₃ ^– present in the soil profile.     

Effect of biochar amendment on soil carbon balance and soil microbial activity

We investigated the behavior of biochars in arable and forest soil in a greenhouse experiment in order to prove that these amendments can increase carbon storage in soils. Two qualities of biochar were produced by hydrothermal pyrolysis from ¹³C labeled glucose (0% N) and yeast (5% N), respectively. We quantified respiratory losses of soil and biochar carbon and calculated mean residence times of the biochars using the isotopic label. Extraction of phospholipid fatty acids from soil at the beginning and after 4 months of incubation was used to quantify changes in microbial biomass and to identify microbial groups utilizing the biochars. Mean residence times varied between 4 and 29 years, depending on soil type and quality of biochar. Yeast-derived biochar promoted fungi in the soil, while glucose-derived biochar was utilized by Gram-negative bacteria. Our results suggest that residence times of biochar in soils can be manipulated with the aim to “design” the best possible biochar for a given soil type.     

Effect of biochar amendment on water infiltration in a coastal saline soil

Purpose

Increasing data have shown that biochar amendment can improve soil fertility and crop production, but there is little knowledge about whether biochar amendment can improve water infiltration in saline soils. We hypothesized that biochar amendment could promote water infiltration in saline soil. The aims of this study were to evaluate the effects of biochar amendment on water infiltration and find the suitable amendment rate and particle size of biochar as a saline soil conditioner.

Materials and methods

We measured water infiltration parameters in a coastal saline soil (silty loam) amended with non-sieved biochar at different rates (0.5, 1, 2, 5, and 10%, w/w) or sieved biochar of different particle sizes (≤?0.25 mm, 0.25–1 mm, and 1–2 mm) at 1 and 10% (w/w).

Results and discussion

Compared with the control, amending non-sieved biochar at 10% significantly decreased water infiltration into the saline soil (P?<?0.05). In contrast, sieved biochar of ≤?0.25 mm significantly improved water infiltration capacity, irrespective of the amendment rate. Sieved biochar of 1–2 mm was less effective to improve soil porosity and when amended at 10%, it even reduced the water infiltration capacity. The Philip model (R²?=?0.983–0.999) had a better goodness-of-fit than the Green-Ampt model (R²?=?0.506–0.923) for simulation of cumulative infiltration.

Conclusions

Amending biochar sieved to a small particle size improved water infiltration capacity of the coastal saline soil compared with non-sieved biochar irrespective of the amendment rate. This study contributes toward improving the hydrological property of coastal saline soil and rationally applying biochar in the field.

     

温度变化对森林土壤氮矿化的影响

Nitrogen mineralization in forest soil wa studied in laboratory by incubating undisturbed soil cores enclosed within PVC columns at different temperatures to compare the effect of flucttuating temperature with that of constant temperaature,and to find out whether soil nitrification shows linearity over time .The results showed that there was no significant difference between soil nitrification at fluctuating temperature and that at constant temperature,and suggested that it must be careful to make the conclusion that soil nitrification has linearity over time.     

Effect of cropping systems on nitrogen mineralization in soils

 Understanding the effect of cropping systems on N mineralization in soils is crucial for a better assessment of N fertilizer requirements of crops in order to minimize nitrate contamination of surface and groundwater resources. The effects of crop rotations and N fertilization on N mineralization were studied in soils from two long-term field experiments at the Northeast Research Center and the Clarion-Webster Research Center in Iowa that were initiated in 1979 and 1954, respectively. Surface soil samples were taken in 1996 from plots of corn (Zea mays L.), soybean (Glycine max (L.) Merr.), oats (Avena sativa L.), or meadow (alfalfa) (Medicago sativa L.) that had received 0 or 180 kg N ha^–1 before corn and an annual application of 20 kg P and 56 kg K ha^–1. N mineralization was studied in leaching columns under aerobic conditions at 30  °C for 24 weeks. The results showed that N mineralization was affected by cover crop at the time of sampling. Continuous soybean decreased, whereas inclusion of meadow increased, the amount of cumulative N mineralized. The mineralizable N pool (N _o) varied considerably among the soil samples studied, ranging from 137 mg N kg^–1 soil under continuous soybean to >500 mg N kg^–1 soil under meadow-based rotations, sampled in meadow. The results suggest that the N _o and/or organic N in soils under meadow-based cropping systems contained a higher proportion of active N fractions. Received: 10 February 1999     

Effect of pH on nitrogen mineralization in crop-residue-treated soils

Summary This study compares N mineralization in soils treated with crop residues [corn (Zea mays L.), soybean (Glycine max (L.) Merr.), sorghum (Sorghum vulgare Pers.)] or alfalfa (Medicago sativa L.) at three adjusted soil pH values (4, 6, and 8); pH was adjusted with dilute H₂SO₄ or KOH. A sample of soil (20 g) was treated with 0.448 g plant material (equivalent to 50t ha^–1), mixed with 20 g silica sand adjusted to the pH of the soil, and packed in a leaching tube. The soil-sand mixture was leached with 100 ml 5 mM CaCl₂ adjusted to the same pH as that of the treated soil to remove the initial mineral N, and incubated at 30°C. The leaching procedure was repeated every 2 weeks for 20 weeks. Results from three soils showed that N mineralization increased as the soil pH increased. In one soil (Lester soil), significant amounts of NH ₄ ⁺ -N accumulated at pH 4 during the first 12 weeks. Treatment with corn and soybean residues resulted in a marked reduction in N mineralization, especially at pH 4. The percentage of organic N mineralized from sorghum residue and alfalfa added to soils increased as the soil pH increased; the values ranged from 7.7% to 37.0% for sorghum and from 17.2% to 30.1% for alfalfa.