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1.
Abstract

Nutrient surpluses on the Delmarva Peninsula have led to a continual accumulation of soil test phosphorus (STP), a potential source for transport of phosphorus (P) to surface waters. This article examines the effects of initial soil test P concentrations and broiler litter additions on STP accumulation. Broiler litter (BL) was applied at rates of 0, 2.5, 5, 7.5, and 10 g kg?1 (dry weight) to three soils: an Evesboro sandy loam (Mesic, coated Typic Quartzipsamments), a Pocomoke sandy loam (coarse‐loamy, siliceous, thermic typic Umbraquults), and a Matapeake silt loam (fine‐silty, mixed, semiactive, mesic Typic Hapludults). Soils and BL were incubated for 16 weeks with subsamples analyzed after 4 and 16 weeks. There was a linear increase in STP (Mehlich‐3), water‐soluble P (WS‐P), iron‐oxide strip‐extractable P (FeO‐P), and Mehlich‐3 phosphorus saturation ratio (M3‐PSR) with broiler litter additions. Regression analysis indicated few significant differences in STP response to added BL between soils within the same soil group having different initial STP levels. Correlation analysis and stepwise regression indicated that increases in WS‐P and FeO‐P from added BL were more closely related to the degree of P saturation of the soil rather than traditional STP measurements. Therefore, decisions regarding manure placement within a watershed should be based on the potential P sorption capacity of the soil as well as potential P transport pathways when the goal is the reduction of P transfer to waterbodies.  相似文献   

2.
Changes in cation exchange capacity (CEC) during composting were evaluated with respect to compost amending, and compost processing. CECdm (CEC on dry matter basis), CECom (CEC on organic matter basis), and CECC (CEC on carbon basis) are parameters used for describing properties of composts. In this study effective cation exchange capacity (ECEC) was determined during drum composting; sampling from the infeed (FM) and the outfeed (DC0), and during curing in experimental heaps; sampling when the compost was turned first time (DC1), second time (DC2), and third time (DC3). The ECECdm was 18.1 (cmol+/kg) in FM, 35.5 in DC0 and 70.5 in DC3; this rise in ECECdm being beneficial from compost amendment standpoint. The ECECom was 20.6 (cmol+/kg) in FM, 41.5 in DCO and 89.8 in DC3, whereas ECECC was 39.3 (cmol+/kg) in FM, 77.2 in DCO and 183.1 in DC3. When ECEC was expressed on carbon mole basis (ECECmolC), it was c. 0.5 (cmol+/Cmol) in FM, c. 0.9 in DC0 and c. 2.2 in DC3. These changes in ECECom, ECECC and ECECmolC are valuable from the compost quality standpoint. Because the basis of CECdm, as well as, of CECom and CECC, is affected by composting, they can not be used in determining the effects of composting on the actual number of CEC sites. The amount of ash is not affected by composting, and thus ash basis can be used for determining the effects of composting on the actual number of cation sites. It was shown in this study, that during composting of manure the actual number of effective cation exchange sites increased from DC1 to DC3 by 34 percent, whereas at the same time ECECdm, ECECom and ECECC increased by 99 percent, 116 percent, and 137 percent, respectively. Based on CEC data reported in this paper and in compost literature, it was concluded, that changes in the number of CEC sites due to composting is overemphasized, when unanchored CECdm, CECom or CECC is used.  相似文献   

3.
选取小麦秸秆为试验材料,采取发酵罐处理方法,在静态通气条件下研究了堆腐过程中堆体温度变化、氧化还原类酶活性变化、温度与酶活性变化的关系、不同酶活性之间的关系。结果表明:(1)添加微生物菌剂处理较不添加微生物菌剂处理(CK)升温快、温度高、高温持续时间长;添加微生物菌剂处理堆体温度第2d上升到50℃以上,第3d达最高温度67.1℃,50℃以上持续6d;CK堆肥第3d达到50℃,第4d达最高温度59.5℃,50℃以上持续5d。(2)过氧化氢酶活性初期较低,中期迅速升高,并维持在较高水平,堆肥第10d到堆肥结束,添加微生物菌剂处理的过氧化氢酶活性明显高于CK;添加菌剂处理多酚氧化酶活性在堆肥前期和后期高于CK,说明添加菌剂可加速木质素的降解及其产物的转化;添加菌剂处理的脱氢酶活性在堆肥中期显著高于CK;添加菌剂处理的过氧化物酶从堆肥第12d到堆肥结束活性均高于CK的过氧化物酶活性,表明添加微生物菌剂可促进物质的氧化。(3)脱氢酶活性和过氧化物酶活性在堆肥中期达到最高值,两者变化趋势相同;过氧化氢酶活性、脱氢酶活性、过氧化物酶活性在堆腐后期比较稳定,多酚氧化酶活性堆腐后期呈增长趋势。  相似文献   

4.
鸡粪与油菜秸秆高温堆肥中营养元素变化的研究   总被引:1,自引:0,他引:1  
以鸡粪和油菜秸秆为原料,采用人工好氧翻堆方式进行高温堆肥试验,研究堆肥制作过程中养分的变化规律。结果表明,堆肥过程中pH值在堆肥前期上升而后期下降;氨态氮、硝态氮、总氮相对含量在堆肥前期下降,后期上升;有效磷在堆肥前期略上升而后期略下降;总钾量呈不断上升趋势;腐植酸总量随发酵时间延长而下降。鸡粪和油菜秸秆堆肥时间在30d左右为宜。  相似文献   

5.
Changes of chemical forms of metallic zinc and zinc sulfide during the composting process of municipal solid waste in oxygen conditions have been determined. Speciation of zinc was carried out by means of sequential extraction. It has been found that contamination of the waste with Zn is dangerous to the environment because zinc accumulates in bioavailable forms - organically bound and carbonate. Zinc sulfide remains mainly in a less mobile sulfide form. The composting process increases the mobility of zinc insignificantly.  相似文献   

6.
The aim of this work was to characterize the humic acids during composting using both chemical and spectroscopic analytical methods. Humic acids (HA) were extracted from olive mill pomace (OMP) after 5, 10, 21, 32, 48, 60, 84, 95, 109 and 153 days of composting and their elemental composition, functional groups, molecular weight, 13C CP-MAS NMR and FTIR spectra were determined. Elemental composition of HA showed a decrease of carbon content from 56.8% to 47.1% and an increase of oxygen content from 32.7 % to 43.3%. A slight increase of carboxylic groups was observed with no variation of phenolic groups. The molecular weight of HA determined by gel chromatography showed that after 95 days of composting the molecular weight of about 40% of the polymers was greater than 102 KDalton. The 13C CPMAS NMR and FTIR spectra of HA showed compositional and structural changes indicating a slight increase of polysaccharides and aromatic groups and a decrease of long aliphatic chains during the composting.  相似文献   

7.
Effects of composting on odorous chemicals in dairy manure were investigated in replicated pilot-scale studies. Three 16-day composting trials were conducted, using 205 L vessels containing 83 kg mass. Fresh or 12-day-aged manure, from lactating cows, was mixed with sawdust (3man:1saw w/w). Vessels were either aerated continuously with high (2.3 kg/hr)/low (0.8 kg/hr) air flow controlled by thermostats or intermittently on a 5 min high air flow/55 min off clock controlled cycle. Six vessel replicates were conducted on each manure/air flow treatment combination. Temperatures, air flow, O2 consumption, and CO2 production were recorded every 10 minutes. Trapped NH3 emissions were determined daily. Exhaust air was passed through water-cooled condensers to analyze emitted volatiles, and condensate volume, pH, and volatile fatty acids (VFAs) were quantified at 12 or 24 hour intervals. Solids were collected from each vessel initially, at remix at the end of day 7, and at the end of each trial (day 16) for analysis of moisture, pH, ash, C/N, and odorants. Phenolics and indolics were extracted with ethyl ether. VFAs were recovered with pH 2.0 water. Analysis was by flame or mass selective detection gas chromatography. Temperature increased most rapidly in continuously aerated vessels yet maintained a lower mean temperature (49 vs 58°C) than intermittent aeration. Both returned to near ambient temperature by day 16. Continuous aeration nearly doubled (11 vs 18 L) the amount of condensate released over 16 days. Fresh manure/sawdust mixes contained 6553, 795, 77, 51, 19, and 17μg/g of acetate, propionate, isobutyrate, isovalerate, phenol, and p-cresol. Aged manure mixes contained 9350, 3397, 2810, 445, 285, 441, 34, 176, and 18 μg/g acetate, propionate, butyrate, valerate, isobutyrate, isovalerate, phenol, p-cresol, and skatole, as well as a number of C11 to C17 fatty acids. Both aeration methods maintained conditions that resulted in the destruction of most of the odorous chemicals studied in the composting mass in 7 days with only small quantities of acetate, isobutyrate, and skatole present by the end of day 16. Continuous aeration, as opposed to intermittent, more than doubled (115 vs 55 g) the emissions of NH3-N and increased the emissions of VFAs in condensate four-fold. Whereas, limited aeration did not destroy the odorants as rapidly, they remained in the compost until destruction.  相似文献   

8.
Safe management of animal and plant waste is one of the world's most important environmental challenges. Composting has been proposed as a useful technique for beneficially recycling wastes. This study showed that significant temporal changes in the nutrient availability occurred during the composting of cow manure with poplar leaf litter within 120 days. In particular, total C in the final compost was directly related to the addition of tree litter and inversely related to the time of composting, whereas extractable P and NO3 increased with increasing amounts of tree litter and ammonium showed the opposite trend. During the later stages of the composting process higher concentrations of water soluble K, Ca, Mg, and Na were observed. The major benefit observed was that heavy metal concentrations initially present in the manure were significantly reduced during composting. Heavy metals in the final compost decreased in the order: Fe > Mn > Zn > Cu > Ni > Cd. The increased availability of plant nutrients following composting coupled with the lower extractability of heavy metals indicates that composting may be a sustainable option for agricultural waste recycling and increased productivity.  相似文献   

9.
Composting inside high-rise, caged layer facilities can produce atmospheric ammonia (NH3) concentrations exceeding standards for human and poultry health. Control measures that reduce NH3 volatilization are necessary for in-house composting to be sustainable. Due to differences specific to in-house composting — low carbon to nitrogen ratios of composting material, continuous manure addition, and frequent turning — it is not known whether NH3 control measures used previously for poultry manure will work. The objectives of this study were to evaluate various amendment and process controls on NH3 produced during simulated in-house composting in the lab, and to evaluate select chemical control measures during composting inside a high-rise layer facility. Ten amendments (aluminum sulfate; chloride salts of aluminum, calcium, magnesium, and potassium; gypsum; sodium bisulfate; zeolite (clinoptilolite); straw; and cellulose) and four process controls (moisture; temperature; turning frequency; and particle size) were evaluated in lab incubations in 1 L vessels wherein samples of poultry manure compost were incubated to simulate composting. Vials of boric acid solution were used to capture NH3 evolved during incubations. With the exception of zeolite and cellulose, all amendments reduced NH3 capture. Low moisture and temperature also reduced NH3 capture, although managing temperature and moisture to achieve low NHg would adversely impact microbial activity and other desired benefits of composting. When evaluated inhouse, aluminum sulfate, calcium chloride and magnesium chloride did not reduce NH evolution from compost measured on three different dates with a gas sensor. Spatial variability along treated segments of windrow apparently masked amendment effects. At the end of a six-week composting cycle, total nitrogen content was higher in compost treated with aluminum sulfate than control or chloride salt treatments. Aluminum sulfate and process controls such as moisture content, carbon source and particle size have potential to reduce NH3 loss from poultry manure composted inside high-rise layer structures. In-house compost management to reduce NH3 volatilization must consider the cost of amendments, effectiveness, and impacts on the composting process.  相似文献   

10.
The main objective of this study was to explore the interactive influence of broiler litter and chemical nitrogen (N)–phosphorus (P) fertilizers placed with furrower and with disk + furrower on maize yield and soil chemical properties. The experiment consisted of two methods of fertilizer placements and seven fertilizer treatments conducted for two successive years under field conditions. Results showed that furrower method improved soil chemical properties and subsequently increased maize grain yield and dry-matter production compared with the disk + furrower method. The N and P levels in soil increased with the application of NP fertilizers and broiler litter. Soils amended with broiler litter and NP fertilizers had greater maize grain yield and dry-matter production than the control. In conclusion, furrower placement combined with the application of broiler litter and 20% of the optimum chemical NP fertilizers were the most efficient nutrient management practice for increasing maize performance in the studied area.  相似文献   

11.
以氢氧化镁+磷酸、磷酸、磷酸二氢钾+氯化镁和磷酸二氢钙+氯化镁为固氮添加剂,以猪粪和玉米秸秆为原料,采用强制通风静态垛堆肥装置进行高温好氧堆肥试验,研究了不同化学添加剂对猪粪堆肥过程中的保氮效果。结果表明,化学添加剂可以显著降低堆肥化过程中氨气的排放率。氢氧化镁+磷酸、磷酸、磷酸二氢钾+氯化镁和磷酸二氢钙+氯化镁的氮素损失分别占初始氮的13.15%、11.50%、10.69%和7.59%,与对照相比,各添加剂处理的固氮率为58.27%~75.90%。磷酸二氢钙+氯化镁处理的氮素损失最少,但堆肥过程中有机物降解受到明显的抑制作用。在堆肥结束时,各添加剂处理的有机物降解率仅为对照处理的58.48%~98.70%。最终堆肥产品的种子发芽指数为69.87%~118.24%,表明所有处理在堆置39 d后均达到腐熟。根据模糊评价的结果,该试验中的磷酸二氢钾和氯化镁是堆肥过程中最佳的固氮材料。  相似文献   

12.
以板栗苞和牛粪为原料,在北京市密云板栗生态同中进行了为期40d的高温好氧堆肥。板栗苞取自密云水库库区板栗生态园,牛粪取自周边养牛场的奶牛粪便,初始混合物料C/N为25~30,含水量在55%-60%,采用人工翻堆的方法进行通风。结果表明,由于板栗苞与牛粪都是木质纤维素含量较高的物料,所以在堆制结束时,堆肥中的粗纤维含量仍有10.11%,整个过程中粗纤维降解率为57.25%。水溶性硝态氮在堆肥过程中总体呈上升趋势,而铵态氮损失比较严重,比初始物料减少了33.30%。在堆肥结束时,C/N基本稳定在20左右。在堆制20d后,发芽指数(GI)已上升到了80%以上。说明板栗苞和牛粪堆肥40d后基本可以达到腐熟,但堆肥巾仍残存部分有彤的板栗苞,需进一步采取措施促进板栗苞中木质纤维素的降解。  相似文献   

13.
Short paper fiber (SPF), a by-product of the paper mill industry, was cocomposted with broiler litter (BL) to determine decomposition rate and NH3-N loss as functions of C/N ratio and pH of the compost mixes. The SPF generally had a high C/N ratio >200 while the BL, consisting of bedding material (sawdust) and poultry manure, had a low C/N ratio of 10–12. A total of seven series (27 tests) of pilot-scale studies were conducted using two different SPFs mixed with BL. Additives used for pH control were alum (aluminum sulfate), HiClay® Alumina and sulfuric acid. Mixing ratios [SPF/(SPF+BL), kg/kg(dry basis)] used were 0.8 to 0.4. Test conditions were C/N of 17 to 49, pH of 6.6 to 8.3, initial temperatures of ?1 to 22°C, composting temperature of 60°C, water content of 50-55% w.b. and remixing two times per week. Composting temperature was controlled using forced ventilation with a high/low fan setting. Composting trials lasted two weeks. Ammonia loss, O2, CO2, compost temperatures and dry solids loss were measured. Evaluations of ammonia emissions versus initial C/N and pH showed: (1) NH3-N loss decreased as initial C/N increased, even above C/N = 38; (2) NH3-N loss decreased rapidly below pH = 7 and increased rapidly for initial pH above 8. Addition of alum and/or sulfuric acid was found to decrease NH3- N loss while HiClay® Alumina had little or no effect. Results on dry solids loss are not presented in this article.  相似文献   

14.
The objective of this study was to identify and quantify volatile organic compounds (VOCs) produced during composting of poultry litter. The VOCs produced from in-vessel composting with a controlled aeration system were tested using the F-ITR method by VOC analyzer. Alkanes and alkylated benzenes were emitted in the highest amounts from poultry litter, while aldehydes, terpenes, ketones were emitted in much lesser amounts. Studies showed that VOCs generation was the greatest early during the composting process and greatly reduced thereafter. Composting temperatures were found to affect VOCs. All VOCs were least with the high temperatures generated during composting.  相似文献   

15.
The effect of composting for a maximum period of 90 days on the water retention characteristics of five waste materials — coconut dust (CD) (also known as coir), mixed sawdust (SD), rice hulls (RH), sapwood sawdust (SW) and heartwood sawdust (HW) was investigated with or without the addition of nitrogen. Total porosity (TP), easily available water (EAW) and water buffering capacity (WBC) were increased with time in all five materials, while air space (AS) was decreased in all the materials except in rice hulls, where it increased. Of all the materials, CD retained the most moisture and RH the least after 90 days. SD, SW and HW had similar characteristics, and separation for utilization is unnecessary. Nitrogen addition did not affect TP and AS but slightly increased EAW and WBC. Formulation and management of potting media using these materials should take into account these moisture retention changes for maximum benefit to plants grown in them.  相似文献   

16.
为解决北方低温季节牛粪大量堆积问题,将筛选的糖、淀粉、蛋白质和纤维素分解菌株复配,优化出组合菌剂(T1+DF2+D2+D5+XB1+XA2),研究低温下优化组合菌剂对低温牛粪堆肥起温的影响。结果表明,在室外-20℃低温下,牛粪接种优化组合菌剂后物料迅速升温,48h达55.8℃,第4d达64.9℃,高温期维持8~9d,发酵周期缩短至15d,而未加菌和加常温发酵剂的对照则一直未进入高温期。说明添加低温复合发酵剂能使低温下牛粪堆体迅速升温,进入高温期,完成无害化,缩短发酵周期。  相似文献   

17.
在强制通风静态垛装置中研究了牛粪堆肥化中氮素形态和微生物生理群的动态变化。在堆制的56d里,根据堆温变化分阶段采集堆肥样品,测定各种氮素组分的含量和氮素微生物生理群的数量。结果表明,堆肥过程中,总氮减少了21.6%;有机氮是堆肥中的主要氮素形态,其含量降低了19.1%;氨基酸态氮和氨态氮的含量分别降低了20.9%和86.4%,在有机氮和总氮中的比例分别降低了2.2%和5.2%;氨基糖态氮和硝态氮含量分别增加了147%和79%,在有机氮和总氮中的比例分别增加了2倍和1.3倍。氨气的挥发占总损失的63%,高温期的释放量占总挥发量的69%。堆肥中氨化细菌数量较高,在高温期大幅度增加,其数量变化与堆肥中氨气和氨态氮含量都呈极显著正相关关系。在堆肥过程中,硝化细菌数量总体较小,在降温期增加幅度较大;反硝化细菌数量逐渐增加,堆制结束时达到堆肥初期的2.45倍;固氮菌数量总体增加1.8倍,其中降温期数量较多。堆肥过程中存在的反硝化作用,是氮素损失的另一个重要原因。  相似文献   

18.
ABSTRACT

The physical and chemical parameters were monitored for seven weeks during Trichoderma/Aspergillus inoculated rice straw composting at various pH levels. Three treatments (A, B, and C) were inoculated with lignocellulolytic microbial consortium (Aspergillus niger, F44 and Trichoderma viride, F26) and three were un-inoculated (D, E, and F). pH of the starting materials was amended to 5.75 (A and D), 6.75 (B and E), and 7.75 (C and F) with either acetic acid or sodium hydroxide. Three typical phases of temperature were observed both in inoculated and un-inoculated treatments during composting: mesophilic phase, thermophilic phase, and followed by cooling and maturation phase. The bioconversion were maximum in Trichoderma/Aspergillus inoculated treatments within 14–21 days as indicated by the profiles of electrical conductivity, bulk density, total carbon and nitrogen, and germination index. After day 21, the germination index of Trichoderma/Aspergillus inoculated treatment (B) without any pH amendment was increased to 74.5 indicating the maturity of compost and suitability for field application.  相似文献   

19.
在静态通气条件下,以养殖场鸡粪、猪粪、牛粪为材料,小麦秸秆作为堆肥调节物质,分别研究了接种微生物菌剂(接种菌剂处理)和不加菌剂(对照处理)堆肥过程中蔗糖酶活性的变化特征及其与温度的关系。结果表明,接种菌剂处理与对照处理在堆肥过程中蔗糖酶活性的变化趋势基本一致,即在高温腐解期蔗糖酶活性持续较高,在低温腐殖化期蔗糖酶活性急剧下降,且维持较低水平。接种菌剂能明显地提高堆肥过程蔗糖酶的活性,酶活性峰值高且出现时间较对照早4~8d。供试的3种物料蔗糖酶活性差异不显著,接种菌剂处理鸡粪、猪粪和牛粪蔗糖酶活性的最高值分别为87.84、81.3和86.8mg·(g·d)^-1,对照处理分别为62.9、60.9和63.79mg·(g·d)^-1,但3种物料接种菌剂和对照处理酶活性峰值出现的时间不尽相同,鸡粪的两种处理相同,猪粪加菌剂比对照提早8d,牛粪加菌剂较对照早4d出现。整个堆肥过程中蔗糖酶活性与堆体温度变化关系密切,对照处理堆体温度与蔗糖酶活性的关系为一元二次方程,表现为高温腐解期为显著性直线负相关,低温腐殖化期为显著性直线正相关,而加菌剂处理堆体温度和蔗糖酶活性间为极显著直线正相关。  相似文献   

20.
Total phosphorus, water-soluble phosphorus and total nitrogen concentrations in cocomposted yard trimmings and broiler litter were quantified in a 2 m wide × 1 m deep × 55 m long channel composter using batch mixing. The batch mixing occurred by using a rotor tiller type turner mounted on rails for the length of the composting channel. Phosphorus and nitrogen concentrations of the compost were measured as they varied with treatment and time during a 63 day compost process followed by a 30 day curing time. The treatments contained a single mix of 50% yard trimmings, 50% poultry litter, by volume, using four aeration and turning treatments. The first treatment was a control, which received no turning or aeration unless the moisture content dropped to 40% and additional water was added to bring the mix up to 50-55% moisture, mix consolidation was required, or mixing to obtain accurate samples and moisture contents, as necessary. Both treatments two and three were aerated by negative pressure ventilation. Treatment two was turned only when the moisture content dropped to 40% and additional water was added to bring the mix up to 50-55% moisture while treatment three was turned every two weeks or sooner if the moisture content approached 40% and additional water was added to bring the mix moisture up to 50-55%. Treatment four was not provided aeration but was turned, on a daily basis and additional water added as necessary, when the moisture content dropped to 40%, to bring the mix moisture up to 50-55%. Total phosphorus increased during the compost process while water-soluble phosphorus decreased during the 63-day active composting cycle from a high of slightly more than 1600 mg P/kg to a low of slightly less than 100 mg P/kg. Once the blowers were turned off and the mixes were no longer turned, soluble phosphorus concentrations were similar for all four treatments. However, after the 93 day cycle was complete, treatment one had almost twice the water-soluble phosphorus concentration as found in treatments two, three, and four. Total nitrogen increased during the final 30 days of the process for all four treatments. The increase was between 0.1 and 10 percent. No logical cause and effect has been established and this difference is believed to be random.  相似文献   

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