基于GIS及APCS-MLR模型的兰州市主城区土壤PAHs来源解析

为了解兰州市主城区表层土壤多环芳烃（PAHs）的污染现状,采集兰州市主城区表层土样62份,利用GC-MS （气相色谱-质谱联用仪）分析土样中16种优控PAHs的含量,采用描述性统计方法表征PAHs污染特征,运用APCS-MLR （绝对主成分分析-多元线性回归）模型判断土壤PAHs的来源,并验证模型结果的准确性,最后结合地统计方法确定各PAHs来源的主要影响区域.结果表明,兰州市主城区表层土壤Σ₁₆ PAHs的含量为1069~7377 μg·kg^-1,平均为2423 μg·kg^-1;其中,以4~6环的高分子量PAHs为主,占Σ₁₆ PAHs的质量分数为72.81%.APCS-MLR模型验证结果表明,实测值与预测值吻合性较高,该模型对于研究区土壤PAHs源解析有很好的适用性.兰州市主城区表层土壤PAHs的来源主要为交通排放源（35.42%）、石油排放源（29.88%）和煤炭与生物质燃烧混合源（33.91%）,高值区主要分布在交通密集范围和工业区.结果表明研究区土壤PAHs来源复杂,且受人为活动的影响较大,应根据各污染源的贡献率和影响区域加强控制,以减少污染源排放量,从而降低土壤PAHs的污染程度.     

广州市土壤多环芳烃污染特征及风险评估

为全面研究广州市土壤多环芳烃（PAHs）污染特征,采集广州市222个表层土壤样品进行分析,利用效应区间低/中值法（ERL/ERM）和（BaP）毒性当量法评价土壤PAHs污染生态风险状况,终生癌症风险增量模型评价土壤PAHs污染健康风险状况,特征化合物比值法和PMF模型对PAHs来源进行解析.结果表明,广州市表层土壤ω（∑16PAHs）为38~11 115 μg·kg^-1,平均值为526 μg·kg^-1,16种多环芳烃单体均为强变异;广州存在潜在生态风险,个别采样点的PAHs污染已存在较大的生态风险,整体处于轻度污染的状态;基于健康风险评价结果表明,成年和儿童的总致癌风险的贡献率都呈现为：皮肤接触 > 误食土壤 > 呼吸摄入,儿童的健康风险大于成年,健康风险总体处于可接受范围;源解析表明广州市土壤PAHs的主要来源为：煤炭源（37.1%） > 柴油源（32%） > 炼焦源 （17.3%） > 交通排放、生物质燃烧和石化产品挥发的混合源（13.6%）,整体土壤PAHs来源属于混合源.研究结果丰富了对广州市表层土壤PAHs污染特征的认识,有助于推动土壤污染防治行动的开展.     

城郊农田土壤多环芳烃污染特征及风险评价

为明确城郊农田土壤多环芳烃（PAHs）的污染特征,按照网格布点法在南京城郊采集29个样点,测定了15种PAHs的含量.结果表明,二氢苊（Ace）均未检出,农田土壤PAHs含量为24.49~750.04 μg ·kg^-1,均值为226.64 μg ·kg^-1;高环PAHs与总PAHs空间分布类似,农田土壤PAHs主要以高环PAHs为主.相关性分析结果表明,农田土壤PAHs与有机质（SOM）、pH、阳离子交换量（CEC）和全氮（TN）无显著相关性,容重（ρ_b）与低环PAHs极显著相关.源解析结果表明,农田土壤PAHs主要来源为燃烧源和石油源的混合源.CSI指数结果表明,农田土壤PAHs不存在生态风险.健康风险评价结果表明,农田土壤PAHs对儿童和成人不存在潜在致癌风险,主要暴露途径是：皮肤接触>摄食>呼吸吸入.     

银川市农田土壤中四环素类抗生素的污染特征及生态风险评估

采集银川市农田表层土壤样品共43个,采用高效液相色谱法检测了土霉素（OTC）、四环素（TC）、金霉素（CTC）和强力霉素（DOC）的含量,结合空间克里金插值方法,分析了银川市农田土壤中这4种四环素类抗生素（TCs）的污染特征及空间分布状况,采用风险商值法评价了农田土壤中OTC、TC、CTC和DOC的生态风险.结果表明,四环素类抗生素在所有土壤样品中均有检出,土壤中ΣTCs含量在40.68~1074.42 μg·kg^-1之间,平均值为462.24 μg·kg^-1,在ΣTCs中平均占比为：CTC（69.26%） > OTC（16.34%） > TC（12.86%） > DOC（1.54%）,CTC为主要污染物;在空间分布上OTC、CTC和DOC这3种抗生素的浓度呈现中部高四周低的趋势,而TC则在西北部浓度最高;在不同种植类型土壤中ΣTCs的平均含量为：设施菜地（596.01 μg·kg^-1） > 牧草地（487.04 μg·kg^-1） > 耕地（437.52 μg·kg^-1） > 园地（404.99 μg·kg^-1）;生态风险评价结果显示,农田土壤中OTC、TC、CTC和DOC的风险平均值分别为0.14、0.69、0.14和1.02,其中23.26%样品的TC与6.98%样品的DOC处于高风险水平,应当引起重视.     

扬州市不同功能区表层土壤中多环芳烃的含量、来源及其生态风险

对扬州市6个不同功能区（公园、菜地、文教区、居民区、加油站和工业区）共59个表层土壤样品（0~10 cm）中15种美国环境保护署优控的多环芳烃（PAHs）的含量和来源进行了分析,并利用苯并[a]芘（BaP）毒性当量浓度（TEQ_BaP）评价了土壤中PAHs的生态风险.结果表明,扬州市土壤中Σ15PAHs总量范围为21~36118 μg·kg^-1,中值为295 μg·kg^-1,PAHs组成中以4~6环为主.不同功能区Σ15PAHs总量平均值高低顺序为工业区 > 加油站 > 文教区 > 菜地 > 居民区 > 公园.相关性分析表明,整个扬州市土壤中Σ15PAHs总量与土壤总有机碳（TOC）（P<0.05）和黑碳（BC）（P<0.01）含量都呈显著性正相关,但除了加油站土壤中Σ15PAHs总量与BC含量呈显著性正相关（P<0.01）外,不同功能区土壤中Σ15PAHs总量与TOC、BC含量都无显著相关性.特征比值法结果表明,不同功能区土壤中PAHs来源虽有些差异,但都主要来源于石油泄漏以及石油、煤和生物质等的燃烧.扬州市土壤中15种PAHs总TEQ_BaP值的范围是2~4448 μg·kg^-1.以荷兰土壤环境标准中的10种PAHs总TEQ_BaP值33 μg·kg^-1为标准,扬州市有45.8%的土样超标,各功能区点位超标率高低顺序为工业区（70%） > 加油站（60%） > 文教区（55.6%） > 菜地（50.0%） > 居民区（30%） > 公园（10%）.因此,扬州市不同功能区中都有部分表层土壤存在潜在的生态风险,工业区和加油站风险相对较高,而居民区和公园风险相对较低.     

典型废旧塑料再生基地周边农田土壤中PAHs污染特征及健康风险评价

为了解废旧塑料再生行业对周边农田土壤环境的影响，在莱州市废旧塑料再生基地内部及周边农田采集22个土壤样品，利用高效液相色谱法对样品中16种多环芳烃（PAHs）含量进行了检测，并对其污染特征及健康风险进行了分析.结果表明，基地周边农田土壤中16种PAHs总含量为60.50~303.48 μg·kg^-1，除?（Chr）、二苯并（a，h）蒽（DahA）外，其余组分的检出率均为100%.萘（Nap）、苊烯（Acy）、苊（Ace）为主要组分，分别占总量的49.57%、21.32%、14.95%.参考Maliszewska-Kordybach的土壤PAHs污染程度划分方法，仅有22.73%样品达到轻微污染且集中于基地内部.在空间分布上，基地内部农田土壤中PAHs含量显著高于外部，总体表现为距基地越远，农田土壤中PAHs含量越低.基地内部各采样点PAHs的构成具有相似性，主要以低环芳烃为主，占PAHs总量的89.56%以上，表明基地内部农田土壤有相对固定的PAHs来源.主成分分析法共提取到3个主成分，表明基地周边农田土壤中的PAHs主要与燃煤、生物质燃烧以及废旧塑料焚烧有关.健康风险评估表明，成人和儿童对PAHs的暴露风险主要通过呼吸途径，儿童的暴露剂量均高于成人，但非致癌及致癌风险水平均在可接受范围.     

宁东能源化工基地核心区表层土壤中多环芳烃的空间分布特征、源解析及风险评价

为了解宁东能源化工基地核心区表层土壤多环芳烃的污染现状,按网格布点法在宁东能源化工基地核心区采集了146个代表性表层土壤样品,分析了16种优控多环芳烃（PAHs）的含量.结果表明,16种优控PAHs均检出,表层土壤中ΣPAHs含量介于ND~123.12mg·kg^-1之间,平均值为10.19mg·kg^-1;空间上存在3个PAHs高含量区,为研究区的西北部、西南部以及东部,且不同PAHs区域分异性显著;源解析表明宁东基地PAHs污染为混合源,石油污染、燃煤、交通污染及汽油源对ΣPAHs的贡献分别为39.4%、33.3%、19.2%和8.1%;质量基准与质量标准法生态风险评价表明,该区域PAHs产生的生态影响较小,出现负面生态效应的可能性较低;健康风险评价结果表明,该区域土壤PAHs对于不同年龄段的人群不存在潜在的致癌风险,主要的暴露途径是皮肤接触 > 误食 > 呼吸吸入.     

淮北孙疃矿区地表尘中多环芳烃类化合物的污染特征及致癌风险评价

淮北孙疃矿区是华北两淮地区典型的煤炭资源开采基地.以往涉及煤矿区地表尘的环境研究多集中在重金属和水溶性离子等,对多环芳烃类化合物（PACs）研究较少.利用气相色谱-三重串联四极杆质谱（GC-MS/MS）检测了孙疃矿区及周边环境地表尘中16种母体多环芳烃（16PAHs）、烷基多环芳烃（aPAHs）及部分含氧多环芳烃（OPAHs）的含量.结果表明,孙疃矿区地表尘中ΣPACs含量范围为283.8~36852.5 μg ·kg^-1（均值为4114.2 μg ·kg^-1）.其中,ΣaPAHs（均值2593.8 μg ·kg^-1）约为Σ16PAHs（均值1074.9 μg ·kg^-1）的2.4倍,是PACs污染的主要贡献者.地表尘中16PAHs和aPAHs在组成上均以相对分子质量低的PACs为主.OPAHs含量较低,均值为445.6 μg ·kg^-1.同时,PACs污染主要集中在矿区周边及煤矸石填埋道路附近.利用正定矩阵因子分解（PMF）推测研究区主要受成岩源影响,其次是煤和生物质燃烧,交通源及石油产品泄漏的占比较小.特征比值结果显示,当Σ16PAHs/ΣPACs<0.25时主要受煤矿区污染.PMF结合终生致癌风险（ILCR）结果显示,研究区对儿童存在潜在致癌风险,风险主要来自煤和生物质燃烧及煤炭开采.我国淮河流域煤矿区众多,研究结果可为煤炭开采区PACs的污染防治提供参考.     

三亚河沉积物PAHs和PCBs的分布、来源及风险评价

多环芳烃（PAHs）和多氯联苯（PCBs）具有"三致"特性和生物累积效应,作为两类典型持久性有机污染物,是环境领域的研究热点之一.本研究考察了三亚河底泥沉积物中PAHs和PCBs的含量分布和污染状况,在对其进行空间污染分布分析的基础上进行来源解析,并采用沉积物质量基准法和质量标准法进行生态风险评价.结果表明,沉积物中总PAHs和总PCBs含量范围分别为265.00~6735.00 μg·kg^-1和1.75~92.75 μg·kg^-1,含量相对较高河段分别为西河上游和东河上游,与研究区域的工业分布和河流走势有较强的相关性.组成及来源解析表明,PAHs以低环芳烃为主,主要来源于石油燃烧污染;PCBs以七氯联苯和六氯联苯为主,主要来源于电容器中PCBs的迁移.生态风险评价结果表明,整体上三亚河沉积物中PAHs生物毒副作用不明显,生态风险较低,但个别采样点PAHs单体超标严重,对生物体暴露会产生严重威胁,需引起重视;PCBs生物毒性效应概率为10%~50%,偶尔会产生负面生态效应.     

鄱阳湖沉积物中多环芳烃的时空分布及源解析

对鄱阳湖沉积物中16种多环芳烃（PAHs）含量、时空分布及影响因素进行了研究,并对湖体不同区域的PAHs进行定量源解析.PAHs在沉积物中广泛存在,所有点位表层沉积物中ω （∑₁₆PAHs）范围为203~2 318 μg·kg^-1,其中湖体表层沉积物中PAHs含量高于入湖河流表层沉积物中PAHs含量.鄱阳湖PAHs环数比例大小依次排列为：4环>5环>6环>3环>2环,4环PAHs组成占主导地位,其含量占∑₁₆PAHs的比例高达86.11%.2~3环以及部分4环PAHs包括Flua和Pyr更容易受到SOM的影响,4~6环PAHs更容易受到ORP及重金属等环境因子的影响.在空间分布上,∑₁₆PAHs的较高含量位于湖体邻近都昌县与鄱阳县区域,此区域地形相对封闭,与周围区域水流交换量小,不利于污染物的迁移、转化及降解.在时间分布上,PAHs含量水平的变化与江西省GDP的发展呈现出高度一致性,经济发展和人类活动影响可能是导致PAHs含量水平不断增加的主要原因.鄱阳湖表层沉积物PAHs的主要来源包括石油污染及石油、煤炭和生物质燃烧源,不同区域PAHs来源存在一定的空间差异.本研究可为鄱阳湖表层沉积物中PAHs污染情况提供参考,对鄱阳湖生态环境保护和治理具有重要意义.     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes

In this study an effort has been made to use plant polyphenol oxidases; potato （Solanum tuberosum） and brinjal （Solanum melongena）, for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.     

Removal of heavy metals from sewage sludge by low costing chemical method and recycling in agriculture

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Single and joint effects of pesticides and mercury on soil urease

The influence of two pesticides including chlorimuron-ethyl and furadan and mercury （Hg） on urease activity in 4 soils （meadow burozem and phaeozem） was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase （up to 13%-21%） in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship （P〈0.05） between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose （ED50） values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.     

Isolation and preliminary characterization of a 3-chlorobenzoate degrading bacteria

A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several （halo）aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no （chloro）catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.     

Organochlorine pesticides in soils under different land usage in the Taihu Lake region, China

A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field ＞ tree land ＞ fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT ＞1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.     

Sorption of 1-naphthol by plant cuticular fractions

The contribution of aliphatic-rich plant biopolymer to sorption of hydrophobic organic compounds is significantly important because of their preservation and accumulation in the soil environment,but sorption mechanism is still not fully understood.In this study, sorption of 1-naphthol by plant cuticular fractions was examined to better understand the contributions of respective fraction.Toward this end,cuticular materials were isolated from the fruits of tomato by chemical method.The tomato cuticle sheet consisted of waxes (6.5 wt%),cuticular monomer (69.5 wt%),and polysaccharide (24.0 wt%).Isotherms of l-naphthol to the cuticular fractions were nonlinear (N value (0.82-0.90)) at the whole tested concentration ranges.The KodKow ratios for bulk cuticle (TC1),dewaxed cuticle (TC2),cutin (TC4),and desugared cuticle (TC5) were larger than unity,suggested that tomato bulk cuticle and cutin are much powerful solption medium.Sorption capability of cutin (TC4) was 2.4 times higher than the nonsaponifiable fraction (TC3).The 1-naphthol interactions with tomato cuticular materials were governed by both hydrophobic-type interactions and polar (H-bonding) interactions. Removal of the wax and polysaccharide materials from the bulk tomato cuticle caused a significant increase in the sorption ability of the cuticular material.There was a linear negative trend between K_(oc) values and the amount of polysaccharides or fraction's polarities ((N O)/C);while a linear positive relationship between K_(oc) values and the content of cutin monomer (linear R~2=0.993) was observed for present in the cuticular fractions.Predominant sorbent of the hydrophobic organic compounds (HOCs) in the plant cuticular fraction was the cutin monomer,contributing to 91.7% of the total sorption of tomato bulk cuticle.     

Alterations of organ histopathology and metallolhionein mRNA expression in silver barb, Puntius gonionotus during subchronic cadmium exposure

Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.     

Seed selections for crystallization of calcium phosphate for phosphorus recovery

Seed induces and promotes the crystallization of calcium phosphate, and acts as carrier of the recovered phosphorus （P）. In order to select suitable seed for P recovery from wastewater, three seeds including Apatite （AP）, Juraperle （JP） and phosphate-modified Juraperle （M-JP） were tested and compared. Batch and fixed-bed column experiments of seeded crystallization of calcium phosphate were undertaken by using synthetic wastewater with 10 mg/L P phosphate. It shows that AP has bad enduring property in the crystallization process, while JP has better performance for multiple uses, and M-JP is a hopeful seed for P recovery by crystallization of calcium phosphate.