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101.
土霉素降解菌TJ-1在猪粪无害化处理中的作用   总被引:6,自引:0,他引:6  
利用普通理化分析结合Biolog微平板技术研究了土霉素高效降解菌Staphylococcus sp.TJ-1在新鲜猪粪无害化处理中的作用.结果表明,土霉素高效降解菌的接种能显著提高猪粪中土霉素的降解效率(p<0.05),21d堆肥结束时可将土霉素降解率从62.7%提升至82.0%.堆肥结束后,不接种降解菌的普通堆肥工艺和接种降解菌的高效堆肥工艺中NH+4-N含量分别为189.34、42.36 mg·kg-1,NO-3-N含量分别为439.38、238.06 mg·kg-1.Biolog结果显示,土霉素降解菌TJ-1对土霉素中碳源的代谢有利于堆体中氨基酸类及芳香族化合物等氮源的降解,缓解了堆体中有毒有害物质对其他微生物的损伤,保证了微生物群落的多样性和活性,对维护堆体生态系统的稳定性具有良好作用.因此,接种高效降解菌进行堆肥是一种良好的消除抗生素残留的猪粪无害化工艺.  相似文献   
102.
Manures and fertilizers are applied to agricultural lands in excess of recommended amounts, resulting in widespread pollution of surface and ground water and contributing a substantial source of greenhouse gases associated with global warming. By developing policies that exploit the value of farm produced nutrients, input costs can be minimized. Better accounting for or crediting of farm produced nutrients is leading to economically beneficial conservation of fertilizer. In addition, hog producers who own enough land may benefit from properly managing manure nutrients. Poultry litter is valuable as fertilizer and can be marketed by independent dealers to farmers in nutrient deficit areas, with very modest assistance from the government. Dairy producers may modify their past income support programs to finance central compost facilities. Although nutrient problems were neglected in the past, recent Federal initiatives and joint initiatives with states exploit many of these and other opportunities to avoid excessive application of nutrients to the land.  相似文献   
103.
ABSTRACT: Land application of organic soil amendments can increase runoff concentrations of metals such as Fe and Zn, metalbids such as B and As, and non-metals such as P and S that have the potential for causing adverse environmental impacts. Aluminum sulfate, or alum (Al2(SO4)3*(14H2O), can reduce concentrations of some materials in runoff from sites treated with organic amendments. The objectives of this study were to (a) quantify concentrations of selected constituents (Al, As, B, Ca, Cd, Co, Fe, K, Mg, Mn, Mo, Na, P, Pb, 5, Se, Ti, and Zn) in runoff from plots treated with horse manure (mixed with stall bedding) and municipal sludge, (b) assess runoff quality effects of alum addition to those treatments, and (c) determine time variations in concentrations of the constituents. Horse manure and municipal sludge were applied to twelve 2.4 by 6.1 m fescue plots (six each for the manure and sludge). Alum was added to three of the manure-treated and three of the sludge-treated plots. Simulated rainfall (64 mm/h) was applied to the 12 treated plots and to three control (no treatment) plots. The first 0.5 h runoff was sampled and analyzed for the constituents described above. Addition of manure or sludge had no effect on runoff concentrations of the majority of constituents. In some cases (e.g., Al, As, Fe, Zn), however, concentrations were near or in excess of threshold values recommended for marine wildlife protection. Alum addition increased runoff of Al, Ca, K, and 5, due likely to its composition and by the addition of lime to counteract the acidity of alum. Concentration decreases of more than 50 percent were noted for P for the horse manure treatment. No alum effect was detected for P in runoff from the sludge-treated plots, possibly due to relatively stable P forms in the sludge. Runoff concentrations of Al, As, Fe, K, Mn, and P followed an approximately first-order decline with respect to time. Runoff concentrations of Ca and 5, however, peaked during the second runoff sample (four minutes following initiation of runoff), suggesting that differences in mobility and/or transport mechanisms exist among the materials investigated.  相似文献   
104.
混合堆肥过程中挥发性固体含量的层次效应及动态变化   总被引:7,自引:1,他引:6  
罗维  陈同斌  高定  郑国砥 《环境科学》2004,25(3):155-159
城市污泥与猪粪混合堆肥表明:升温期和高温期堆体上部有机物降解的差异较大,降温期堆体下部各层有机物降解的差异较大,且堆体内挥发性固体(VS)含量已形成明显的层次效应,腐熟期堆体中部有机物降解的差异较大,堆体内VS含量的层次效应仍很明显;不同堆肥期堆体内VS含量的差异由大到小分别为:降温期≥腐熟期>高温期>升温期,不同部位有机物降解程度由大到小为:上部>中部>下部;VS含量随时间的变化满足一级反应动力学方程,城市污泥和猪粪混合堆肥过程中VS的降解速率约为0.3kg·d-1,VS含量降低了8.2%.  相似文献   
105.
The heavy metals pollution in poultry and livestock feeds and manures under intensive farming in Jiangsu Province was investigated. 97 feed and manure samples were sampled from 31 farming plants in 10 major cities of Jiangsu. 14 metals, including Zn, Cu, Pb, Cd, Cr, Ni, Mo, Mn, Ba, Co, Sr, Ti, As and Hg, were analyzed after samples acid digestion. The results showed that the most feed samples contained high concentration of metals exceeding National Hygienical Standard for Feeds. Meanwhile, it was found that Cu, Zn, Pb, Cd and Cr concentrations in animal manures were also high, for example, Cu concentration in a manure sample reached to as much as 1726.3 mg/kg. Heavy metals loading quantities in soil per year were then calculated when metals contaminated organic fertilizers were applied, and its effects on soil environmental qualitv were further evaluated.  相似文献   
106.
罗珊  胡锦昇  唐翔宇  耿春女  程建华 《环境科学》2023,44(11):6399-6411
磺胺类抗生素和氟苯尼考(FFC)是浙江省普遍使用的抗生素,在土壤上吸附弱而易于迁移,存在较高的环境风险.近年来,粪源抗生素对农田土壤潜在风险的研究多是在实验室条件下添加粪肥的方式进行,无法评估自然施肥状态下抗生素的污染风险.因此以浙江省长期施用不同肥料(鸡粪、猪粪和化肥)的5种旱地农田土壤[临安(LA)、嘉善(JS)、龙游(LY)、开化(KH)和金华(JH)]为对象,选用4种常用的抗生素[磺胺嘧啶(SD)、磺胺二甲基嘧啶(SMT)、磺胺甲基异噁唑(SMZ)和FFC],进行批量平衡实验,探究土壤不同类型和粪肥类型对抗生素在土壤中吸附的影响.结果表明,4种抗生素在实验土壤中的吸附都较弱,吸附次序为:SMT(1.44~13.23 mg(1-(1/n))·L1/n·kg-1)>SMZ(0.73~6.05 mg(1-(1/n))·L1/n·kg-1)>SD(0.16~5.57 mg(1-(1/n))·L1/n·...  相似文献   
107.
北方城市垃圾的回收和利用   总被引:1,自引:0,他引:1  
随着城市垃圾的迅速增长,垃圾污染问题异常尖锐突出,特别是北方城市尤为严重。本文围绕北方城市如何选择合适的垃圾处理技术进行探讨。提出现阶段在大中城市开展综合处理。在小城市采取以卫生填埋为主、堆肥为辅的处理技术,是解决城市垃圾问题的有效途径。  相似文献   
108.
比较二花脸和皮特兰猪在2h运输过程中血浆ACTH、皮质醇、胰岛素和T3、T4水平的动态变化模式,以分析内分泌激素变化的品种特征.选用雄性二花脸猪10头,皮特兰猪6头,体重达20kg时安装颈静脉瘘管,1wk后运输试验,运输过程中不同时间点采集血样,放射免疫分析法测定血浆激素水平.上车后两品种猪ACTH水平缓慢上升,60min后达到峰值,下车后15min恢复至基础水平,运输过程中ACTH水平及变化幅度均未表现显著的品种差异;运输前皮质醇水平二花脸显著高于皮特兰猪,上车后两品种皮质醇均迅速上升,出发后15min达到峰值,下车后15min均快速恢复至基础水平,运输过程中皮特兰皮质醇上升的幅度显著高于二花脸猪;两品种胰岛素水平上车后均呈下降趋势,二花脸胰岛素水平总体上显著高于皮特兰猪;T3水平在上车后也表现快速下降,无论是T3水平还是其变化幅度均不表现显著的品种差异;皮特兰猪上车后T4水平稍微下降而二花脸猪显著下降,皮特兰T4水平总体显著高于二花脸猪.运输应激伴随血浆ACTH和皮质醇水平升高,而胰岛素、T3和T4水平下降,皮质醇水平升高的幅度能够反映猪的应激敏感性.图1参25  相似文献   
109.
Abstract

We investigated the anaerobic degradation of tetracycline antibiotics (tetracycline [TC], oxytetracycline [OTC] and chlortetracycline [CTC]) in swine, cattle, and poultry manures. The manures were anaerobically digested inside polyvinyl chloride batch reactors for 64?days at room temperature. The degradation rate constants and half-lives of the parent tetracyclines were determined following first-order kinetics. For CTC the fastest degradation rate was observed in swine manure (k?=?0.016?±?0.001 d?1; half-life = 42.8?days), while the slowest degradation rate was observed in poultry litter (k?=?0.0043?±?0.001 d?1; half-life = 161?days). The half-lives of OTC ranged between 88.9 (cattle manure) and 99.0?days (poultry litter), while TC persisted the longest of the tetracycline antibiotics studied with half-lives ranging from 92.4?days (cattle manure) to 330?days (swine manure). In general, the tetracyclines were found to degrade faster in cattle manure, which had the lowest concentrations of organic matter and metals as compared to swine and poultry manures. Our results demonstrate that tetracycline antibiotics persist in the animal manure after anaerobic digestion, which can potentially lead to emergence and persistence of antibiotic resistant bacteria in the environment when anaerobic digestion byproducts are land applied for crop production.  相似文献   
110.
钙镁磷肥与有机物料配施对作物镉铅吸收的控制效果   总被引:1,自引:0,他引:1  
李瑞美  王果  方玲 《生态环境》2002,11(4):348-351
通过田间定位试验,采用钙镁磷肥(G)、泥碳(P)、猪粪(M)、钙镁磷肥+泥碳(GP)、钙镁磷肥+猪粪(GM)等处理对福建省龙岩市新罗区特钢厂附近的污染田进行改良。试验表明,大部分处理能提高土壤的pH值;处理钙镁磷肥、钙镁磷肥+泥碳和钙镁磷肥+猪粪对提高作物产量均有显著效果;大部分处理能抑制水稻、花生对镉铅的吸收;说明通过调节土壤pH值,改变土壤重金属活性是有机-中性化改良技术的主要机理。  相似文献   
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