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481.
Antibiotics are newly emerging organic pollutants in manure, soil, vegetables and water. Animal manure application might be leading to the accumulation of antibiotics in the farmland. However, the effect of sulphamethazine (SMZ) on the soil microbial community was scarcely investigated. This study was aimed to evaluate the impact of SMZ on poultry manure, on the structure and function of microbial community, carbon mineralisation, and changes in nitrogen forms in soil via an incubation experiment lasting 56?d. The treatments consisted of poultry manure at 1% wt (PM), PM containing 20?mg?kg?1 SMZ (PM?+?20SMZ) and PM containing 100?mg?kg?1 SMZ (PM?+?100SMZ), along with the untreated soil (control). Solid phase extraction was performed to measure the SMZ concentration in soils using high-pressure liquid chromatography. The cumulative CO2-C was increased in all treated soils over the incubation period compared to the control. The PM?+?100SMZ had the highest increase in cumulative CO2-C from the soil at 56?d of incubation. The treatment of PM?+?20SMZ showed a short-term decrease in nitrification rate in the soils at 1?d by altering the microbial community composition with 17% dissimilarity and decreasing the abundance of bacteria compared to PM-treated soil. The PM?+?100SMZ increased C mineralisation in the soil.  相似文献   
482.
区域农田畜禽承载量预测模型构建与应用:以赤峰市为例   总被引:3,自引:0,他引:3  
为对区域现有生猪养殖数量的合理性进行评价及对生猪养殖承载量进行预测,从畜禽养殖-耕地-作物系统出发,基于农田养分平衡理论及有机和无机肥合理配施方法,构建区域农田畜禽承载量预测模型。以赤峰市为例,设定有机和无机肥配施比例为5∶5,并保持现有农田N或P2O5养分盈余量不变,分别基于N和P2O5养分盈余量不变实地应用该模型。结果表明,基于N时可新增生猪养殖数量43.6万头,承载量为630.8万头;基于P2O5时可新增生猪养殖数量369.3万头,承载量为1 041.3万头。位于西拉木伦河南岸的松山区、翁牛特旗、喀喇沁旗、宁城县和敖汉旗是可新增生猪养殖的主要区域。从环境压力角度考虑,推荐基于N的预测值作为计算赤峰市可新增生猪养殖量和承载量的依据。  相似文献   
483.
香蕉茎秆、桉树皮和猪粪不同配比堆肥研究   总被引:1,自引:0,他引:1  
通过固定猪粪添加量,依次增加桉树皮添加量,减少香蕉茎秆添加量,研究了桉树皮、香蕉茎秆和猪粪不同配比,不同C/N比值等对堆肥温度、pH值、微生物数量以及种子发芽率等堆肥发酵指标的影响,并用腐熟的有机肥进行香蕉幼苗盆栽试验。结果表明,堆肥材料C/N比值为25.24和27.01的处理堆肥温度较高,均达到56℃以上,持续高温时间分别为10和11 d,堆肥中各养分含量相对较高,达到NY 525—2012《有机肥料》标准。盆栽试验也表明,利用堆肥材料C/N比值为25.24和27.01的堆肥配制的有机肥对盆栽香蕉幼苗有一定的促生效果。  相似文献   
484.
Contents and changes of some hazardous elements in 388 animal feed and manure samples collected in 2009–2010 from 194 animal farms in 10 provinces of China were determined. The concentrations of Cu, Zn, Cr, and Pb in animal manures were in the ranges of 10–1800, 50–6300, 0.1–340, and 1.0–310 mg kg?1, with median concentrations of 200, 500, 15, and 11 mg kg?1, respectively. As, Cd, and Hg were in ranges from undetectable to 280, undetectable to 10, and 0.01–2.5 mg kg?1, respectively. The concentrations of Cu, Zn, and As were highest in the manure from pig, followed by the manure from poultry and dairy cows. From 1990 to 2010, Cu, Zn, As, Cd, and Cr contents in manure increased strongly, especially in pig and poultry manure. Most of the increases occurred before 2003 and then stabilized or decreased which reflects the extensive use of feed additives before 2003 and the gradual stabilization since then.  相似文献   
485.
采用量热计法和三维荧光光谱,分别对猪粪发酵产热不同阶段温度、热值以及溶解性有机质(DOM)的转化特征进行了研究. 结果表明:在不同C/N(猪糞与芦苇秸秆物料配比)的4组发酵产热试验中,纯猪粪发酵产热温度高于室温时间达到60d,累积热量损失最多达8.862kJ/g,是增温技术最为理想的配比;随着发酵产热的进行,纯猪粪发酵产热样品中类蛋白化合物荧光比值(P1,n+P2,n,0.625~0.546)逐渐减少,类富里酸物质荧光比值(P3,n,0.140~0.173)与类胡敏酸物质荧光比值(P5,n,0.051~0.097)逐渐增多,腐殖化程度逐渐加强,但是与其他各组相比其腐殖酸类物质增加最少,腐殖化程度最低;不同C/N物料产热过程中,尽管不同区域的荧光强度与热值的相关性不同,但不同C/N物料释放的热量均来源于微生物对简单有机化合物的分解.   相似文献   
486.
This overview summarises the present knowledge on major sources of pollution, which are of concern for the Mediterranean Sea. Eutrophication, red tides, organic loads, hydrocarbon spills, heavy metal contamination and their biological effects are described on the light of the ecological characteristics of the Mediterranean. In particular special attention is paid to the "new pollution" processes; i.e. , the introduction of novel substances with biological activity that might have synergetic effects with "classical pollutants". Different compartments and marine ecosystems are considered and compared. The degree of anthropogenic impact and its apparent trends are discussed. Possible monitoring plans and remedial actions for a sustainable management of coastal zones subjected to increasing pollution are also suggested.  相似文献   
487.
The analytical results of 53 manure samples determined by wet digestion and dry ashing procedures were compared in order to evaluate their relative suitability for recovering different nutrient elements in manure and manure compost. Wet digestion recovered greater amounts of phosphorus (P), potassium (K), calcium (Ca), manganese (Mn), and zinc (Zn) in more samples than dry ashing. Nutrient contents in the samples were highly variable, with coefficients of variation (CV) ranging from 38% for magnesium (Mg) to 161% for copper (Cu) analyzed by the wet digestion procedure, and from 47% to 138% for Mg and Cu analyzed by the dry ashing procedure. The mean values of P, K, Ca, Mn, and Zn averaged for the 53 samples were significantly higher using wet digestion than dry ashing procedure, but both procedures recovered comparable amounts of iorn (Fe), Mg, and Cu. Correlations analysis between both procedures for each element showed reasonable to fair agreements for Ca (R 2?=?0.93), K (R 2?=?0.93), P (R 2?=?0.90), Mg (R 2?=?0.84), Fe (R 2?=?0.87), Mn (R 2?=?0.73), and Cu (R 2?=?0.66), but poor agreement for Zn (R 2?=?0.44). The low agreement between procedures for Zn suggests that wet digestion, which gave a higher recovery, should be a preferred procedure for analyzing Zn in manures.  相似文献   
488.
对九龙江流域规模化养猪场猪饲料、沼气出液和猪粪中砷的含量进行了测定。猪饲料中砷的含量范围为0.50~7.72mg·kg-1,平均值为3.49mg·kg-1;沼气出液中砷的含量范围为0.47~56.13μg·L-1,平均值为13.45μg·L-1;猪粪中砷的含量范围为0.32~114.46mg·kg-1,平均值为13.45mg·kg-1。同一养猪场,小猪猪粪中的砷含量一般高于大猪和母猪猪粪;沼气出液和猪粪中的砷含量具有一定的相关性。由估算知,养猪场向九龙江流域年排放的砷总量约为821kg。9家养猪场中有2家猪粪和1家沼气出液中砷的含量相对较高,生态风险等级较高,已超过国家相应标准。总之,应该加强养猪业的管理,以防止养猪场对九龙江流域造成砷污染。  相似文献   
489.
碳酸盐岩山地土壤施用有机肥的溶蚀作用探讨   总被引:1,自引:0,他引:1  
选择碳酸盐岩山地常见耕植、未耕植土层,通过概化制作为系列模拟柱试验土层,按当地正常施肥方法,向土层定量施入有机肥并浇灌及控制其它相关条件变化,再定期观测预埋土层不同深度碳酸岩石片的溶蚀量和土层其它指标的变化,作了施用有机肥的土中碳酸岩石溶蚀变化研究。结果揭示,在未耕植红黏土表层施用有机肥,大大减弱了土中碳酸岩石的溶蚀作用,且减弱程度随土深加大而降低。但对其下伏碱性岩粉层而言,施肥又引起了溶蚀量的微小增加变化;另在耕植土表层施用有机肥,对其土中碳酸岩石的溶蚀作用改变不大,且无论施肥与否溶蚀作用随土深加大又略显增大变化。而其下部红黏土中碳酸岩石的溶蚀量要远大于耕植土中的溶蚀量,并受施肥的影响较小。表明,农业施肥对未耕植土土中包被、包裹的碳酸岩石溶蚀影响较大,对下伏碱性岩粉层的层中、层下碳酸岩石的溶蚀影响较小。同时,施肥对耕植土土中、土下碳酸岩石的溶蚀影响不大。人类可采取禁令开垦较薄土层措施,来有效规避耕作施肥对土中碳酸岩石溶蚀作用的抑制,减少反石漠化的不利因素。此将为丰富碳酸盐岩山地成土演化理论和石漠化灾害的防治提供依据。  相似文献   
490.
高浓度有机牧场养牛废水处理工程的设计与运行   总被引:1,自引:0,他引:1  
针对南昌某有机牧场的养牛废水悬浮物、有机物、氨氮浓度高等特点,采用厌氧消化-UASB-SBR组合处理工艺,进水COD为18~20 g/L、NH3-N为410~510 mg/L、SS为4~6 g/L,通过工程调试和运行后,出水COD、NH3-N和SS去除率分别为98.1%、76.1%、97.5%,各指标均达到了《畜禽养殖业污染物排放标准》(GB 18596—2001)的要求。对南方地区的养殖场废水处理工程具有一定的参考价值。  相似文献   
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