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基于稳定同位素和贝叶斯模型的引黄灌区地下水硝酸盐污染源解析 总被引：5，自引：0，他引：5
地下水硝酸盐（NO3-）污染已经成为全球严重的水环境问题之一,由于饮用水中高含量NO3-会转化成亚硝酸盐而增加各种疾病和癌症风险,其来源的确定对于NO3-污染的预防和控制非常重要。本文以黄河下游第二大灌区——潘庄灌区为例,首次采用NO3-的氮氧稳定同位素结合贝叶斯模型追溯地下水NO3-的来源并量化各种来源的贡献比例。结果表明,地下水NO3-含量分布在0.1~197.0 mg·L-1,平均值为34.2 mg·L-1。与《生活饮用水卫生标准》中规定的地下水NO3-最大含量[20 mg（N）·L-1,相当于NO3-含量90 mg·L-1]相比,有10%的样品NO3-含量超标。井深<30 m、30~60 m和>60 m的地下水NO3-平均含量分别为25.9 mg·L-1、39.7 mg·L-1和20.1 mg·L-1。空间上,宁津县、武城县、平原县和禹城市有大片区域地下水NO3-含量较高。地下水NO3-的δ15N组成范围为0.72‰~23.93‰,平均值为11.62‰;δ18O组成范围为0.49‰~22.50‰,平均值为8.46‰。同位素结果表明粪便和污水、农业化肥是地下水中NO3-的主要污染来源。这反映了人类活动是引起地下水NO3-污染的主要原因。贝叶斯模型结果显示,粪便和污水对潘庄灌区地下水中NO3-平均贡献率高达56.2%,化肥的平均贡献率为19.3%,大气降水和土壤的平均贡献率分别为6.2%和12.3%。由于污水、粪便和化肥是地下水中NO3-的主要来源,为保护和改善研究区地下水水质,建议加强污水管道建设,强化畜禽粪便的管理以及提高化肥利用效率。 相似文献
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紫苏对不同浓度镉胁迫的生理响应 总被引：5，自引：0，他引：5
为探讨紫苏的耐镉生理机制, 通过水培试验, 研究了镉离子浓度为0 mg·L-1(对照)、2.0 mg·L-1、5.0 mg·L-1、10.0 mg·L-1 条件下紫苏的生长、镉富集作用及叶片的保护酶活性。结果表明, 2.0 mg·L-1、5.0 mg·L-1、10.0 mg·L-1 镉胁迫下, 紫苏单株生物量比对照分别减少28.4%、42.4%、66.0%, 不同处理间均存在极显著差异;3 个镉离浓度下紫苏的镉富集量依次为462.4 μg·株-1、705.0 μg·株-1、609.7 μg·株-1, 富集系数依次为91.9、70.0、51.1, 具备镉超积累能力。此外, SOD、POD、CAT 酶活测定结果显示, 随镉离子浓度升高, 紫苏叶片的SOD 活性和MDA 含量显著升高, POD 和CAT 活性显著下降, 破坏了体内保护酶系统的平衡, 抑制紫苏生长。 相似文献
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溶质类型与矿化度对半干旱盐渍化地区果园土壤水分有效性的影响 总被引：3，自引：0，他引：3
盐渍化土壤水分有效性是制约土地生产能力的关键因素之一。研究不同盐分类型及矿化度的盐溶液对土壤水分有效性的影响, 可为微咸水合理灌溉以及促进土壤生产潜力的发挥提供科学依据。本研究采用离心法在室内研究了脱水过程中灌溉水的溶质类型(NaCl和Na2SO4)与矿化度(0、1 g·L-1、3 g·L-1、5 g·L-1、10 g·L-1)对半干旱盐渍化地区果园土壤水分有效性的影响。结果表明: 不同矿化度的NaCl和Na2SO4处理均可使田间持水量、暂时萎蔫系数、永久萎蔫系数、迟效水和无效水较对照有所降低。不同矿化度的NaCl处理以及1 g·L-1的Na2SO4处理土壤全有效水和速效水都较对照增加, 3 g·L-1、5 g·L-1和10 g·L-1的Na2SO4处理土壤全有效水和速效水都较对照减小。不同矿化度的NaCl和Na2SO4处理均可使土壤通气孔隙和毛管孔隙相对减少, 非活性孔隙增大, 其中矿化度为5 g·L-1的NaCl和Na2SO4处理对其影响最为明显, 通气孔隙分别较对照减小16.8%和14.8%, 毛管孔隙分别较对照减小5.2%和6.5%, 非活性孔隙分别较对照增加15.7%和14.4%。NaCl对于土壤比水容量和毛管断裂的延迟效果比NaSO4明显。且土壤溶液盐分含量增加, 土壤持水能力下降、供水性能增加而土壤抗旱性降低。 相似文献
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氟 对玉米产量品质及土壤性质的影响 总被引：1，自引：0，他引：1
适量氟对动物和人类健康有益, 而过量氟对动物和人类健康有害。为研究氟对玉米产量品质及土壤性质的影响, 采用盆栽试验研究了添加0、100 mg·kg-1、200 mg·kg-1、500 mg·kg-1、1 000 mg·kg-1 和1 500 mg·kg-1 氟(NaF)对玉米产量、粗蛋白和淀粉含量及土壤pH、水溶性钙和微生物数量的影响。结果表明: 随氟处理浓度的增加玉米产量显著降低, 减产9.9%~85.4%; 玉米籽粒蛋白质含量显著增加, 从91.8 g·kg-1 增加到108.8 g·kg-1。加入氟100 mg·kg-1 和200 mg·kg-1 时, 淀粉含量表现为下降趋势,而当加入氟500 mg·kg-1、1 000 mg·kg-1 和1 500 mg·kg-1 时, 淀粉含量表现为上升趋势。玉米不同部位氟含量基本上随氟浓度的增加而增加, 玉米根部和籽粒含氟量与氟添加量的相关性达极显著水平, 相关系数分别为r根=0.998**和r粒=0.915**; 叶含氟量与氟添加量的相关性达显著水平, r叶=0.852*; 玉米不同部位氟含量的大小顺序为根>叶>叶鞘>茎>籽粒。氟浓度在200 mg·kg-1 时, 籽粒含氟量已超过无公害农产品标准1.0 mg·kg-1。石灰性土壤添加氟后, 可使土壤pH 增加,从8.05 增加到8.70; 水溶性钙含量显著下降, 由2.71 g·kg-1 下降到1.02 g·kg-1。随氟浓度的增加土壤放线菌数量显著降低, 与对照相比, 降低0.92%~65.22%; 低浓度的氟可以促进土壤细菌、真菌的生长, 而高浓度的氟可以抑制细菌、真菌的生长。 相似文献
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由于人类大量开采使用石油、煤炭、天然气等化石燃料,使大气CO2浓度升高,这不但加速全球变暖,还将影响地球上动植物的生存和分布,从而对整个生态系统产生深远影响。为探明CO2浓度升高与豌豆蚜（Acyrthosiphon pisum）虫口密度对紫花苜蓿（Medicago sativa）叶片内化学物质的影响,明确CO2浓度升高和蚜虫密度在紫花苜蓿生理生化中的作用,试验在CO2光照培养箱内设置380 μL·L-1（对照）、550 μL·L-1和750 μL·L-1 3个CO2浓度培育苜蓿幼苗并接入10日龄成蚜10头·株-1、20头·株-1、30头·株-1,并以0头·株-1作为空白对照,1周后测定植物体内营养物质和次生代谢物质含量。结果表明,随CO2浓度升高,蚜虫密度为30头·株-1时紫花苜蓿可溶性蛋白、可溶性糖以及淀粉含量均上升,在750 μL·L-1 CO2浓度下分别比CK上升11.62倍、0.49倍和0.24倍;黄酮、总酚和简单酚含量也显著上升。随蚜虫危害程度加重,同一CO2浓度下紫花苜蓿淀粉、简单酚含量先上升后下降,高CO2浓度蚜虫密度为30头·株-1时比0头·株-1时可溶性糖、总酚以及单宁含量上升1.66倍、1.49 mg·g-1和1.09 mg·g-1,差异均显著（P<0.05）。说明具有固氮作用的豆科植物更易于适应CO2浓度升高的变化,从而在受到刺吸胁迫后增强自身诱导抗虫性以抵御害虫为害。 相似文献
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氟啶胺对土壤中蔗糖酶活性及呼吸作用的影响 总被引：5，自引：0，他引：5
使用农药控制作物害虫和疾病可提高农业生产力, 然而农药的使用对土壤造成的污染已成为巨大且日益严重的问题。重复、广泛使用的农药进入土壤影响土壤生物、生物代谢及其生物活性, 已成为农业生态环境重要的研究内容。为了更好地了解氟啶胺对土壤微生物活性和土壤质量等潜在环境危险, 采用实验室模拟的方法研究了氟啶胺农药残留动态, 以及氟啶胺对土壤呼吸强度、蔗糖酶活性及其动力学和热力学特征参数的影响。结果表明: 高剂量(100 mg·kg-1)氟啶胺在土壤的降解速率常数最大, 氟啶胺在土壤中的半衰期范围为0.38~0.59 d。高剂量(50 mg·kg-1、100 mg·kg-1 和1 000 mg·kg-1)氟啶胺对土壤蔗糖酶表现出不同程度的抑制作用; 低剂量(1 mg·kg-1、5 mg·kg-1)处理表现为抑制-激活-抑制作用, 且波动范围较大; 10 mg·kg-1 氟啶胺对土壤蔗糖酶前期表现为抑制、后期表现为激活作用, 波动范围较大。不同浓度氟啶胺胁迫下蔗糖酶促反应的Michaelis 常数(Km)和最大反应速率(Vmax)发生改变, 但变化不大。土壤中氟啶胺浓度为1 mg·kg-1 时蔗糖酶所需的活化能(Ea)比CK 高, 其他浓度都低于CK; 5 mg·kg-1、10 mg·kg-1、50 mg·kg-1、100 mg·kg-1 和1 000 mg·kg-1 所需的活化焓变(ΔH)随氟啶胺的浓度降低而变小; 在相同温度下蔗糖酶的活化熵变(ΔS)表现为: 1 mg·kg-1G)变化差异较小; 320~330 K (开氏温度)时最大速度常数(Q10)最大, 而290~300 K 时Q10 较小。低剂量氟啶胺对土壤微生物呼吸作用的影响表现为随时间变化呈现抑制-激活趋势, 高低剂量表现为抑制作用。土壤微生物的呼吸活性因氟啶胺的加入而产生波动。本研究结果有助于进一步分析研究受农药污染土壤的质量和酶活之间的相关性。 相似文献
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[目的] 探究川中丘陵地区施用经无害化处理的生活污水后，不同类型土壤在不同深度土层中各养分指标的变化特征，为农村生活污水的无害化处理和资源化利用提供科学支撑。 [方法] 对三格化粪池处理后的农村生活污水进行资源化利用。在耕地中设置G0(37.5 L/m2)，G2(75 L/m2)，G0(空白)3种施用处理；在林地中设置L1(37.5 L/m2)，L2(75 L/m2)，L3(112.5 L/m2)，L0(空白)4种施用处理。结合层次分析法(AHP)与主成分分析法(PCA)对各养分指标权重进行计算，对各处理在不同深度土层中的施用效果进行综合评分。 [结果] 在生活污水不同的资源化利用处理除L3土壤养分评价等级为“良”外，其余处理皆为“优”。各处理下，耕地中各深度土层养分评价得分排序一致表现为：G1＞G0＞G2；林地中0-20 cm土层表现为：L0＞L2＞L1＞L3；20-40 cm土层表现为：L1＞L0＞L2＞L3。耕地施用对提升土壤有机质、全氮、全磷、速效磷、速效钾有明显的效果；林地少量施用对提升20-40 cm除速效钾外其余土壤养分的效果较好。 [结论] 短期来看，在农村生活污水资源化利用时，适量的施用可改善耕地土壤的养分，对于林地无需施用土壤养分就可较好保持。 相似文献
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本文对稀盐(0.01mol·L-1NaHCO3,0.01mol·L-1CaCl2(100℃,25℃))溶性氮表征石灰性土壤的供氮能力做了探讨。研究结果表明,土壤浸出液中的全氮(TN)、有机态氮(Org.N),NO3-N分别与浸出液的总吸光量(QT)、有机质的吸光量(QOM)、NO3-N的吸光量(QNO3)高度相关。除QOM和Q260外,QT,QNO3,TN,NO3-N,Org.N与盆栽冬小麦相对吸氮量高度相关。稀盐溶液浸提法,特别是0.01mol·L-1NaHCO3和0.01mol·L-1CaCl2(25℃)浸提法,具有操作简便、快速、经济等优越性。 相似文献
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耕作措施对温带半干旱地区土壤温室气体(CO2、CH4、N2O)通量的影响 总被引：3，自引：1，他引：3
通过设置在甘肃省定西市李家堡镇的不同耕作措施试验, 利用CO2分析仪、静态箱-气相色谱法对双序列轮作次序下春小麦地、豌豆地生育期内CO2、CH4和N2O通量进行了测定。试验结果表明: 4种耕作措施下春小麦地和豌豆地在生育期内均表现为CO2源、N2O源和CH4汇的功能。传统耕作不覆盖、免耕不覆盖、免耕秸秆覆盖和传统耕作结合秸秆还田下, 春小麦生育期内平均土壤CO2通量(μmol·m-2·s-1)分别为0.203 6、0.221 2、0.241 8、0.224 9, CH4通量(mg·m-2·h-1)分别为-0.041 6、-0.078 0、-0.081 8、-0.053 7, N2O通量(mg·m-2·h-1)分别为0.089 1、0.069 2、0.046 1、0.065 6; 豌豆生育期内平均土壤CO2通量(μmol·m-2·s-1)分别为0.273 6、0.261 6、0.218 1、0.236 0, CH4通量(mg·m-2·h-1)分别为-0.055 0、-0.073 7、-0.066 2、-0.054 5, N2O通量(mg·m-2·h-1)分别为0.123 4、0.084 7、0.080 6、0.035 0。少免耕及小麦秸秆覆盖有利于减少土壤CO2排放通量, 免耕不覆盖、免耕秸秆覆盖及传统耕作结合秸秆还田均能不同程度地增加CH4吸收通量、减少N2O排放通量。综合来看, 免耕不覆盖、免耕秸秆覆盖和传统耕作结合秸秆还田3种保护性耕作措施有助于减少土壤温室气体的排放量。春小麦地CO2通量随着土壤温度、土壤含水量的逐渐升高而增大; CH4吸收通量随着土壤含水量的逐渐升高而增大, 而随着土壤温度的逐渐升高而减小。豌豆地CO2通量的变化与土壤含水量存在极显著正相关关系; 而春小麦地N2O通量则与平均土壤温度呈显著正相关, 豌豆地则为极显著正相关。 相似文献
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畜禽舍粪便污水及废气净化的研究 总被引：20，自引：2，他引：20
猪场污水经文中所述工艺系统处理以后,污水中的化学耗氧量(CODCr)达到98.4mg/L;生物需氧量(BOD5)达到49.6mg/L;悬浮物(SS)达到51.49mg/L以下;硫化物达1.0mg/L以下:铜和铜化物达到0.6mg/L以下。畜舍中的废气净化,选择挥发性的药材制成“姜满净化剂”,能使畜舍的氨(NH3)降解率达到73.9％,舍内含氟量为15.0mL/m3;硫化氢(H2S)降解率达到85.8％,舍内的硫化氢浓度为2.8mL/m3;细菌降低率达到70.7％。 相似文献
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长江三角洲地区污水污泥与健康安全风险研究 Ⅲ. 苏、杭二城市污水污泥所施土壤中Cu和Zn的释放动态及其环境风险 总被引：1，自引：0，他引：1
未经处理的污泥农业利用后,不仅会增加土壤中污染物的含量,而且会威胁人类和其他生物的健康。室内培养试验结果表明,污泥中的重金属进入土壤后,表现出先释放,后固定的变化趋势,而且随培养时间的增加,施污泥土壤中EDTA和CaCl2提取态Cu和Zn含量逐渐增加,150d时其含量达到最高。与对照处理相比,施污泥土壤中EDTA提取态Cu和Zn含量分别增加了21.4mgkg-1和26.1mgkg-1,而CaCl2提取态Cu和Zn含量分别增加了0.10mgkg-1和3.37mgkg-1。重金属不合格的污泥农业利用存在一定程度的重金属污染风险,且其风险大小与土壤类型、污泥种类和培养时间及污泥的土壤施用量等因素密切相关。选择适宜的土壤类型、污泥种类、施用时间及控制污泥施用量等,能够在一定程度上降低污泥中重金属农业利用的环境风险。 相似文献
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膜生物反应器处理猪场污水研究 总被引：6，自引：2，他引：4
为探讨膜生物反应器(MBR)处理猪场污水的可行性和膜生物反应器的运行、操作条件,为膜生物反应器在处理猪场污水中的应用提供必要的基础参数,该文采用U型中空纤维膜和L式中空纤维膜生物反应器,对不同的化学需氧量(COD)及氨氮(NH+4-N)进水浓度、溶解氧水平(DO)、污泥龄(SRT)进行了4种工况试验研究。结果表明,MBR作为猪场污水处理好氧段是可行的,当进水COD平均浓度为1860 mg/L,U型、L式膜平均去除率分别为84.10％,81.20％;NH+4-N进水平均浓度为511 mg/L,U型、L式膜平均去除率分别为93.81％,93.61％。 相似文献
14.
The composition of soil organic matter (SOM) on sewage farms south of Berlin was investigated by solid-state CP/MAS 13C-NMR and pyrolysis-field ionization mass spectrometry (Py-FIMS) of freeze-dried sewage solids and soil samples of differing contamination. These were an untreated soil (USOIL), a former sewage farm used as arable land since 1990 (SF90A), and a recent sewage farm (SF1994). The CP/MAS 13C-NMR spectra showed enrichments of the sewage-treated soils with aliphatic C and C in OCH3-groups and amino acids. In the Py-FI mass spectra the major markers of sewage and SOM in sewage farm soils were (i) N-containing compounds, in particular peptides, (ii) dimethylphthalate (m/z 194), (iii) sterols, and (iv) signals in the mass range m/z 502 to 554 of mono- and diaryl esters which were substituted by long aliphatic chains. The latter signals were intense in the sewage solids, increased in intensity from sample SF90A to SF1994; but they were not present in the USOIL, thus clearly indicating anthropogenic origin. Temperature-resolved Py-FIMS showed that the SOM compounds in the sewage farm soils were generally incorporated into bonds with widely different stabilities which could be relevant for SOM turnover and environmental effects. This is demonstrated for the trapping of dimethylphthalate in a modelled humic substance. 相似文献
15.
《Communications in Soil Science and Plant Analysis》2012,43(12):1525-1539
Swine lagoon sludge is commonly applied to soil as a source of nitrogen (N) for crop production but the fate of applied N not recovered from the soil by the receiver crop has received little attention. The objectives of this study were to (1) assess the yield and N accumulation responses of corn (Zea mays L.) and wheat (Triticum aestivum) to different levels of N applied as swine lagoon sludge, (2) quantify recovery of residual N accumulation by the second and third crops after sludge application, and (3) evaluate the effect of different sludge N rates on nitrate (NO3-N) concentrations in the soil. Sludge N trials were conducted with wheat on two swine farms and with corn on one swine farm in the coastal plain of North Carolina. Agronomic optimum N rates for wheat grown at two locations was 360 kg total sludge N ha?1 and the optimum N rate for corn at one location was 327 kg total sludge N ha?1. Residual N recovered by subsequent wheat and corn crops following the corn crop that received lagoon sludge was 3 and 12 kg N ha?1, respectively, on a whole-plant basis and 2 and 10 kg N ha?1, respectively, on a grain basis at the agronomic optimum N rate for corn (327 kg sludge N ha?1). From the 327 kg ha?1 of sludge N applied to corn, 249 kg N ha?1 were not recovered after harvest of three crops for grain. Accumulation in recalcitrant soil organic N pools, ammonia (NH3) volatilization during sludge application, return of N in stover/straw to the soil, and leaching of NO3 from the root zone probably account for much of the nonutilized N. At the agronomic sludge N rate for corn (327 kg N ha?1), downward movement of NO3-N through the soil was similar to that for the 168 kg N ha?1 urea ammonium nitrate (UAN) treatment. Thus, potential N pollution of groundwater by land application of lagoon sludge would not exceed that caused by UAN application. 相似文献
16.
Marija Zupančič Nataša Bukovec Radmila Milačič Janez Ščančar 《Water, air, and soil pollution》2004,156(1):57-69
The comparison of immobilisation efficiency of various phosphate stabilisation agents for heavy metals in sewage sludge collected from an urban wastewater treatment plant Domale-Kamnik (Slovenia) is reported. The sewage sludge, containing high total concentrations of Zn (2698 ± 8.1 mg kg-1), Ni (1513 ± 5.7 mg kg-1), Cr (1118 ± 3.0 mg kg-1) and Cu (712 ± 2.2 mg kg-1), was mixed with various types of phosphates: highly soluble Ca(H2PO4)2, synthetic hydroxyapatite, with a solubility between Ca(H2PO4)2 and rock apatite, and bone-meal as an alternative low-cost source of poorly crystalline phosphate, in order to reduce metal mobility. The amounts of stabilising agents added to 1 g of the sludge ranged from 0.05 to 1 g. Water and acetic acid extractions were used for the determinationof water-soluble and potentially bioavailable metal fractions in the sewage sludge and its mixtures with various stabilisation agents. 相似文献
17.
《Communications in Soil Science and Plant Analysis》2012,43(9-10):993-1002
Abstract Three long‐term field experiments were established in the spring of 1978 and continued through 1988 to evaluate corn (Zea mays L.) response to high Cu levels from Cu rich swine manure and CuSO4 applications. The field research was conducted on soils with diverse properties, i.e., on a Bertie fine sandy loam (fine‐loamy, mixed, thermic, Aquic Hapludults), a Guernsey silt loam (fine, mixed, mesic, Aquic Hapludalfs), and a Starr‐Dyke clay loam (fine‐loamy, mixed, thermic Fluventic Dystrochrepts‐clayey, mixed, mesic, Typic Rhodudults). Three treatments in the long‐term field experiments on the three soils were i) a control, ii) annual applications of Cu as Cu rich swine manure, and iii) annual applications of Cu as CuSO4 equivalent to that in the manure. After the 11 years, 1109 mt ha‐1 of wet Cu rich swine manure were applied for the manure treatment. The Cu rich manure, which contained an average of 1316 mg Cu kg‐1, was produced by swine fed diets supplemented with an average of 251 mg Cu kg‐1 as CuSO4. An average of 325 kg Cu ha‐1 added to the soils from the manure application over the 11 years exceeded U.S.E.P.A. guidelines for safe copper loading levels for cropland by 45 kg ha‐1. Copper concentrations in corn ear leaves were within the normal range of 3 to 15 mg kg‐1 where the 325 kg Cu ha‐1 were applied to the soils as either Cu rich manure or CuSO4 over the 11 years. Concentrations of Cu in the grain also were in the normal range of 1 to 5 mg kg‐1 where the high level of the two Cu sources were applied to the soils. There was no decrease in corn yield on the three soils from application of either Cu source. The lack of yield decrease from the Cu rich manure and CuSO4 applications may reflect decreased Cu availability at the near neutral pH in the soils under study. 相似文献
18.
以河南省新乡市娘娘庙污灌区一块约328 m2的田块为研究区,采用均值、变异系数、半方差函数及分维数等相结合的方法,分析一次污水灌溉前后10 d内东西向剖面A、B、C和D(南北向每相距10.5 m设置1个剖面,由北至南依次编号为A、B、C和D)的土壤有效镉的垂向空间变异及其分布特征,为田块土壤中有效态镉分布与土壤植物修复相结合的研究思路提供基础性探讨。结果表明:灌水后,土壤有效镉含量在剖面A、B、C和D的均值分别减少0.06 mg?kg?1、0.11 mg?kg?1、0.14 mg?kg?1和0.23 mg?kg?1,呈现中等离散程度;在0.393~1.308 m变程范围内,块基比C0/(C0+C)25%,土壤有效镉剖面总体表现出由随机性引发的变异较小,空间相关性较强;剖面A、C和D土壤有效态镉的分维数降低,空间变异程度减弱。Kriging插值结果表明该区有效镉呈条带状分布格局,且在0~15 cm土层呈现累积现象;沿灌水方向,土壤有效镉含量剖面等值线分布由密集到稀疏。相关分析表明,土壤有效镉含量与土壤有机质含量呈正相关,与土壤含水率呈中等程度相关,与p H呈现强负相关,表现为土壤有机质含量越高土壤有效镉含量越大,p H越高土壤有效镉含量越小;污水灌溉对土壤有效镉、土壤含水率、土壤p H和土壤有机质的影响显著,同时会削弱有效镉与各影响因子间的相关关系。伴随着污水灌溉动态的有效镉分布和变异特征可以为应用植物吸附进行土壤重金属污染修复方面的研究提供基础数据。 相似文献
19.
Seung-Gun Won Ji-Young Park Md Mukhlesur Rahman Kyu-Hyun Park 《Compost science & utilization》2016,24(1):42-53
The treatment of livestock fatalities caused by epidemic diseases must be timely. Simultaneously, the contaminated excreta and bedding materials must also be treated on site without removal. The composting of manure with bulking materials is widely used on the farm, and the temperature during the composting reaches over 60°C under appropriate conditions of moisture and oxygen, with a suitable carbon to nitrogen ratio. These characteristics of composting can be applied to the degradation of dead livestock. Hence, this study was conducted to evaluate the degradability of mortalities during composting with bulking material comprised of swine manure and sawdust. The laboratory and field studies were conducted using mimic swine mortalities (MSM) and real swine mortalities, respectively. The sawdust to swine manure ratios of 20:80, 40:60, 70:30, and 100:0 were treatments identified as T1, T2, T3, and T4. In the laboratory study, high degradation of the mortalities (>85%) occurred in all treatments, except the T1 treatment. The T2 treatment obtained high degradation at a desirable level. In the field study, the degradation of the soft tissues of the mortalities in the T2 and T1 treatments reached 99.7 and 84.5%, respectively. The final C/N ratio of treatment T2 (17.5) was higher than treatment T1 (16.8). The addition of swine manure helped to develop relatively rapid temperature homogeneity between the mortality and the bulking materials, and the sawdust to swine manure ratio of 40:60 proved best for swine carcass degradation. 相似文献
20.
Microbial Biomass and Tolerance of Microbial Community on an Aged Heavy Metal Polluted Floodplain in Japan 总被引：1，自引：0，他引：1
Takafumi Kamitani Hirosuke Oba Nobuhiro Kaneko 《Water, air, and soil pollution》2006,172(1-4):185-200
The objective of the present study was to increase understanding of the effects of heavy metal pollution and soil properties on microorganisms in relation to the biomass and microbial functional community. Soil samples were collected from aged polluted and reference sites on a floodplain. The soil Cu, Zn and Pb total concentrations were much higher at the polluted sites (average 231.6–309.9 mg kg?1, 195.7–233.0 mg kg?1, and 72.4–86.0 mg kg?1, respectively) than at the reference site (average 33.3–44.0 mg kg?1, 76.7–98.0 mg kg?1, and 30.8–41.6 mg kg?1, respectively), while the available heavy metal concentrations in CaCl2 extraction were similar in all sites. Small seasonal variations in the size of microbial biomass were observed. Ambient soil properties (e.g. total C, N, pH, moisture content, and CEC) affected the soil microbial biomass more than the heavy metal pollution. However, the aged pollution tended to impact on the composition of the microbial community. PICT (pollution-induced community tolerance) test using BIOLOG Ecoplates showed enhanced tolerance of the microbial community to Cu stress in the polluted site. In non polluted but low nutrient, low pH and low moisture soil, the microbial biomass was lower and the microbial community was more vulnerable to Cu stress. In spite of the low heavy metal availability due to ageing, the BIOLOG technique provided sensitive detection of microbial community level changes in PICT analysis. 相似文献