Regional,seasonal and interspecific variation in <Superscript>15</Superscript>N and <Superscript>13</Superscript>C in sympatric mouse lemurs

Madagascar provides some of the rare examples where two or more primate species of the same genus and with seemingly identical niche requirements occur in sympatry. If congeneric primate species co-occur in other parts of the world, they differ in size in a way that is consistent with Hutchinson’s rule for coexisting species, or they occupy different ecological niches. In some areas of Madagascar, mouse lemurs do not follow these “rules” and thus seem to violate one of the principles of community ecology. In order to understand the mechanisms that allow coexistence of sympatric congeneric species without obvious niche differentiation, we studied food composition of two identical sized omnivorous mouse lemur species, Microcebus griseorufus and M. murinus with the help of stable isotope analyses (δ ¹⁵N and δ ¹³C). The two species are closely related sister species. During the rich season, when food seems abundant, the two species do not differ in their nitrogen isotope composition, indicating that the two species occupy the same trophic level. But they differ in their δ ¹³C values, indicating that M. griseorufus feeds more on C₄ and CAM (Crassulacean-acid-metabolism) plants than M. murinus. During the lean season, M. murinus has lower δ ¹⁵N values, indicating that the two species feed at different trophic levels during times of food shortage. Hybrids between the two species showed intermediate food composition. The results reflect subtle differences in foraging or metabolic adaptations that are difficult to quantify by traditional observations but that represent possibilities to allow coexistence of species.     

Transformation of Organic Matter of the Larch Forest Soils in the Northern Taiga of Nizhne-Tungusskoe Plateau, Central Siberia

The evaluation of biospheric role of the boreal forests in the accumulation of carbon is connected with the evaluation of organic matter (OM) pool in soils. The research sites were larch forests, they are situated on Nizhne-Tungusskoe Plateau. Larch forests of feather-moss and lichen types (110 and 380 years old) were formed on 'ochric podbur' soils. Litter stocks are 3.5–4.5 kg m^{− 2} with thickness 10–25 cm. Cryomezomorphic northern taiga soils contains 38–73 t (carbon) ha^{− 1}. Pool of fast mineralized OM has average value 38.1 t (carbon) ha^{− 1}, including 20.5 and 6.4 t (Carbon) ha^{− 1} of labile compounds on surface and in the soil, and 11.2 t (carbon) ha^{− 1} of mobile OM. Microbial mass reaches 1.78–3.47 t (carbon) ha^{− 1}, its proportion is 3.6–4.9% of the total OM carbon. Zoomass of feather-moss larch forest is 0.20–0.61 * 10^{− 2}, in lichen larch forest −0.01–0.07 * 10^{− 2} t (carbon) ha^{− 1}. A pool of resistant to biological decomposition and bonded to mineral soil matrix OM is 17.7 t (carbon) ha^{− 1} and it varies from 18.6 to 29.0 in feather-moss larch forest, and from 6.4 to 17.0 t (carbon) ha^{− 1} in lichen larch forest. Two-years field experiment has been performed to determine transformation rates of various plant litter fractions and to clarify the role of soil biota in these processes. The results showed participation of all biota groups in the decomposition of plant residues caused weight loss of larch-needles and root mortmass. Isolation of organic matter from all-size invertebrate groups leads to some decrease of decomposition activity.     

施加盐基离子调控水稻Cd的吸收与累积

盐基离子含量是土壤肥力的重要指标,也是决定土壤Cd生物有效性的重要因素.为探明盐基离子对稻田系统中Cd迁移、转运与累积的影响,本研究通过水稻盆栽试验,按照土壤中盐基离子的物质的量比施加不同浓度梯度KCl、CaCl_2、NaCl和MgCl_2到模拟制备的轻度(0.5 mg·kg~(-1))和中度(1.5 mg·kg~(-1))Cd污染土壤,分析盐基离子对土壤CaCl_2提取态Cd含量和水稻吸收累积Cd的影响.结果表明:施加盐基离子能够增加土壤阳离子交换量(CEC),在轻度和中度Cd污染土壤中,土壤CaCl_2提取态Cd含量分别下降了24.6%～56.1%和17.0%～71.1%,糙米Cd含量分别降低了9.1%～60.5%和7.2%～36.0%.在轻度和中度Cd污染土壤中,糙米Cd含量与土壤CaCl_2提取态Cd含量之间存在线性正相关关系,根、茎、叶Cd含量与Ca含量均呈线性负相关.     

NaHCO3活化荞麦皮生物炭对碘帕醇的吸附

采用NaHCO₃活化荞麦皮生物炭,优化得到生物炭0.25N-BC[m（NaHCO₃）：m（荞麦皮）=0.25：1],通过SEM、BET、XRD、Raman、FTIR和XPS等方法进行表征,分析NaHCO₃对生物炭理化性质的影响,探究其对非离子型碘代X射线造影剂碘帕醇（IPM）的吸附性能和机制.结果表明,与荞麦皮生物炭相比（BC）,NaHCO₃活化生物炭的结构缺陷程度更高（比表面积和孔体积分别由480.40 m²·g^-1和0.29 cm³·g^-1增至572.83 m²·g^-1和0.40 cm³·g^-1,I_D/I_G是BC的1.22倍）,表面含碳和含氧官能团数量发生显著变化,极性增强[（N+O）/C由0.15增至0.24],能够有效吸附IPM,0.25N-BC对IPM最大吸附量达到74.94 mg·g^-1,是BC （7.88 mg·g^-1）的9.51倍.拟二级吸附动力学和Langmuir、Freundlich等温线模型可很好地拟合0.25N-BC对IPM的吸附,吸附过程主要以化学吸附和单层、非均质多层吸附为主;孔隙填充、氢键、π—π和n—π相互作用是0.25N-BC吸附IPM的主要机制.对比不同碱[KOH、Na₂CO₃、NaHCO₃、KHCO₃和Ca （HCO₃）₂]活化荞麦皮生物炭对IPM的吸附,0.25N-BC吸附效率高,达到吸附平衡时间短,能有效去除实际水体（二沉池出水和湖水）中IPM的残留,并具有良好的循环使用性能,吸附-解吸3次后对IPM的去除率仍保持在74.91%.研究表明NaHCO₃活化荞麦皮生物炭是一种绿色有效,可持续去除含碘有机物的优良吸附剂.     

污泥生物炭硼掺杂改性及其对水中1,2-二氯乙烷吸附行为和机制

以市政污泥为前驱体，采用硼酸掺杂改性共热解法，制备了污泥生物炭(BC600)和B掺杂污泥生物炭(BBC600),采用SEM、BET、FTIR、Zeta电位和静态接触角等手段对材料进行了结构表征，研究了BC600和BBC600对水中1,2-二氯乙烷(1,2-DCA)的吸附行为、机制和影响因素.结构表征结果表明，B掺杂改性后，生物炭中B元素含量、比表面积和孔容分别提高了76%、48%和30%;B掺杂改性对生物炭表面电荷及亲疏水性影响不大，BC600和BBC600表面均带有负电荷，接触角均<90°,两者均具有较好的亲水性.吸附实验结果表明，BBC600对1,2-DCA的吸附性能优于BC600,缘于BBC600更大的比表面积和强度更高的含氧官能团；准一级动力学方程可以较好描述BC600吸附1,2-DCA过程，准二级动力学方程能较好拟合BBC600吸附1,2-DCA过程，颗粒内扩散不是影响吸附速率的唯一限速步骤；碱性条件下生物炭材料更加分散和稳定，且其含氧官能团去质子化，供电子能力增强，有利于对1,2-DCA的吸附；腐殖酸(HA)对BC600吸附1,2-DCA呈现低浓度促进，高浓度抑制的作...     

三峡澎溪河流域消落区与岸边土壤磷形态特征

选取了落干期澎溪河流域6个消落区点位,分析了消落区土壤磷形态分布特征,并探讨了各形态磷之间的相关性.结果表明,(1)采用SMT法测定了消落区土壤总磷、无机磷和有机磷含量,其总磷TP含量均值为575.29 mg·kg~(-1),有机磷OP含量均值为91.23 mg·kg~(-1).(2)采用Hedley法分析了消落区土壤磷的5种赋存形态,其中WA-Pi、PA-Pi、Fe/Al-Pi等3种易迁移的无机磷形态之和占可提取Pi的11.61%,且低于岸边土壤;WA-Po、PA-Po两种生物可利用性较高的有机磷形态含量之和占可提取Po的22.28%,而中活性有机磷Fe/Al-Po占可提取Po的66.30%,且消落区土壤各形态Po含量均低于岸边土壤,又以Fe/Al-Po含量差异最大.(3)消落区土壤TP与活性较强的WA-Pt、PA-Pt呈显著相关,表明消落区土壤活性磷含量主要受TP影响;各形态磷之间不具有显著相关性,表明不同形态磷的来源可能不同;消落区土壤Fe/Al-Pt与土壤有机质OM呈显著相关,表明土壤有机质的含量可能影响铁铝结合态磷含量.在淹水条件下,消落区土壤磷组分的释放对上覆水体的潜在影响不容忽视.     

锑矿冶炼区周边土壤吸附Sb (V)的行为研究

本文通过吸附平衡和动力学实验方法对Sb（V）在锑矿冶炼区周边土壤表面开展吸附行为研究,用常用的等温吸附模型和动力学吸附模型分别对等温吸附曲线和动力学吸附曲线进行拟合。结果表明：Langmuir与Freundlich模型对荒地土和林地土吸附Sb（Ⅴ）的等温吸附曲线均有较好的拟合效果,拟合系数R²0.988。荒地土对Sb（Ⅴ）的吸附能力大于林地土,其吸附量是林地土的2.9±0.2倍,这与Langmuir模型预测的该两种土壤的吸附倍数相当,荒地土表现出强烈吸附Sb（Ⅴ）的能力,尤其在锑浓度较高的体系中更为明显。结合土壤基本理化性质及矿物学特征,认为土壤秥粒、铁矿物和碳酸钙是影响土壤吸附Sb（V）的主要因素。有机质对土壤吸附Sb（Ⅴ）有一定促进作用,但这种影响只表现在Sb（Ⅴ）初始浓度低的条件下;而在Sb（Ⅴ）初始浓度高的条件下,有机质对土壤吸附Sb（Ⅴ）的影响不明显。土壤吸附Sb（Ⅴ）的过程分为快速吸附和慢速吸附两个阶段,快速反应发生在70 min以内。初始浓度低（0.01 mmol/L）的条件下,Elovich方程能够很好地拟合荒地土和林地土吸附Sb（V）的动态曲线;初始浓度高（2 mmol/L）的条件下,双常数方程对荒地土吸附Sb（V）的拟合效果较好,拟一级动力学方程和拟二级动力学方程则适用于拟合林地土吸附Sb（V）的过程。     

唐山陡河水库沉积物汞的分布、来源及污染评价

为弄清陡河燃煤电厂大气汞沉降对毗邻的陡河水库沉积物中总汞、甲基汞的贡献及其污染程度,于2013年8月对陡河水库沉积物进行了采样,测定了沉积物中总汞、甲基汞、有机质以及孔隙水中溶解态汞含量等参数,运用地累积指数法评价了陡河水库沉积物的汞污染现状和污染程度.结果表明,陡河水库沉积物中总汞含量(dw)范围为19~97 ng·g~(-1),甲基汞含量(dw)范围为0.02~1.27 ng·g~(-1),均表现为表层高于底层,说明陡河水库沉积物的汞含量正逐年升高,外源汞输入对陡河沉积物负荷产生了一定的影响.受电厂大气汞干湿沉降影响,陡河水库周边土壤汞含量(dw)平均值为22 ng·g~(-1),而陡河水库3个沉积物柱库心总汞含量最高,其次为西支,东支最低.结合上游大黑汀水库较高的沉积物汞含量(总汞平均值为176 ng·g~(-1)),以及陡河水库附近较低的土壤汞含量,初步判断陡河水库沉积物中汞的主要来源为大黑汀水库的高汞水源输入,电厂汞沉积输入贡献相对较小.陡河沉积物总汞、甲基汞与有机质之间均呈显著的正相关关系,表明沉积物中有机质具有较好的吸附总汞和甲基汞的能力,并对甲基汞产生具有重要作用.地累积指数Igeo的评价结果表明,陡河水库各点位沉积物的汞污染程度依次为库心西支东支,库心和西支属于中度污染,东支属于轻微污染.大黑汀水库受周边采矿企业影响,两个采样点沉积物的地累积指数污染评价属于中强污染和强污染.     

不同地表条件下生物炭对土壤氨挥发的影响

为了探究生物炭对不同地表条件下土壤氨挥发的作用及其效应,通过田间小区试验的方法,探讨生物炭与作物种植覆盖双重影响下,土壤氨的产生、土壤铵态氮含量、土壤脲酶活性的响应性变化.试验设置了6个处理,分别为CK+(未施生物炭+种植作物)、BC0.5+[施用生物炭0.5 kg·(m~2·a)~(-1)+种植作物]、BC4.5+[施用生物炭4.5 kg·(m~2·a)~(-1)+种植作物]、CK-(未施生物炭+裸地)、BC0.5-[施用生物炭0.5 kg·(m~2·a)~(-1)+裸地]、BC4.5-[施用生物炭4.5 kg·(m~2·a)~(-1)+裸地].结果表明在作物种植条件下,相对于CK+处理,BC4.5+、BC0.5+处理的土壤氨挥发随时间呈现先增加(前4 d内)后显著下降的态势,降幅分别为9.95%~61.80%、7.97%~50.52%(P0.05);但同期裸地条件下的BC4.5-、BC0.5-处理的土壤氨挥发较CK-处理则增加了40.02%~93.15%、28.09%~57.45%(P0.05).在等量生物炭施用条件下,作物种植土壤的氨挥发量明显低于裸地土壤,BC4.5+、BC0.5+较BC4.5-、BC0.5-处理分别降低了27.10%~92.10%、13.17%~83.45%(P0.05),但是CK+与CK-处理间的土壤氨挥发量差异不显著.上述结果说明作物种植覆盖地表对生物炭介导的土壤氨挥发具有一定的抑制效应.作物种植条件下,BC4.5+、BC0.5+处理较CK+处理的土壤铵态氮和脲酶含量的最大增幅依次为69.25%、72.73%和93.61%、90.56%(P0.05),但同期土壤氨挥发降低;而裸地条件下,BC4.5-、BC0.5-处理的土壤铵态氮和脲酶含量较CK-呈下降趋势明显,最大降幅依次为63.78%、95.70%和78.38%、92.64%(P0.05),同时土壤氨的挥发量上升.可见生物炭影响下的土壤氨挥发不仅与土壤铵态氮和脲酶含量的变化密切相关,且作物种植覆盖地表的影响更为深刻.     

High black carbon and ozone concentrations during pollution transport in the Himalayas：Five years of continuous observations at NCO-P global GAW station

To study the influence of polluted air-mass transport carrying ozone (O3) and black carbon (BC) in the high Himalayas, since March 2006 the Nepal Climate Observatory at Pyramid (NCO-P) GAW-WMO global station (Nepal, 5079 m a.s.l.) is operative. During the first 5-year measurements, the O3 and BC concentrations have shown a mean value of 48 ± 12 ppb (± standard deviation) and 208 ± 374 ng/m3, respectively. Both O3 and BC showed well defined seasonal cycles with maxima during pre-monsoon (O3 : 61.3 ± 7.7 ppbV; BC: 444 ± 433 ng/m3) and minima during the summer monsoon (O3 : 40.1 ± 12.4 ppbV; BC: 64 ± 101 ng/m3). The analysis of the days characterised by the presence of a significant BC increase with respect to the typical seasonal cycle identified 156 days affected by "acute" pollution events, corresponding to 9.1% of the entire data-set. Such events mostly occur in the pre-monsoon period, when the O3 diurnal variability is strongly related to the transport of polluted air-mass rich on BC. On average, these "acute" pollution events were characterised by dramatic increases of BC (352%) and O3 (29%) levels compared with the remaining days.     

Temperature and parasitism by <Emphasis Type="BoldItalic">Asobara tabida</Emphasis> (Hymenoptera: Braconidae) influence larval pupation behaviour in two <Emphasis Type="BoldItalic">Drosophila</Emphasis> species

In holometabolous insects, pupation site selection behaviour has large consequences for survival. Here, we investigated the combined effects of temperature and parasitism by the parasitoid Asobara tabida on larval pupation behaviour in two of its main Drosophila sp. hosts differing in their climate origin. We found that larvae of Drosophila melanogaster—a species with a (sub)tropical origin—placed at 25°C pupated higher in rearing jars than those placed at 15°C. The opposite pattern was observed for Drosophila subobscura larvae—a species from temperate regions—which pupated lower, i.e. on or near the substrate at 25°C, than those placed at 15°C. When placed at 25°C, parasitized larvae of both species pupated closer to the substrate than unparasitized ones. Moreover, the Drosophila larvae that had been exposed and probably stung by A. tabida, but were not parasitized, pupated lower than the control unparasitized larvae. These results provide new insights of host behaviour manipulation by A. tabida larvae.     

三峡水库典型支流磷素赋存形态特征及其成因

采用2018年三峡水库低水位期(6月)、蓄水期(9月)和高水位期(12月)对库区内的典型一级支流——香溪河与神农溪回水区水质、水动力及环境因子的监测数据,对比分析了三峡水库内的典型支流在水库不同调度期时水体中磷素的存在形态及成因.结果表明,香溪河与神农溪库湾水体总磷(TP)质量浓度变化范围分别为0.049～0.168m...     

2008～2018年武汉市BC气溶胶时间演变特征及其来源分析

黑碳(BC)作为最重要的吸收性气溶胶,其辐射强迫显著地改变大气边界层结构和近地面大气污染物的累积。基于2008～2018年武汉市BC和气象要素的观测数据,结合CWT潜在来源模型,分析了BC的时间演变特征和潜在来源分布。结果表明武汉BC平均质量浓度为6 926.4±4 090.6 ng/m³,Ångström指数(AAE)和液体燃料源对BC贡献占比(P)的平均值分别为0.98±0.44和76.6%,BC主要来自液体燃料的燃烧。2014～2017年BC质量浓度呈现显著的下降趋势,液体燃料对BC的贡献逐年增加。BC的季节分布为冬季(8 537.3 ng/m³)>春季(7 513.2 ng/m³)>秋季(6 820.2 ng/m³)>夏季(6 161.9 ng/m³),BC_liquid占比为秋季(80.0%)>冬季(77.3%)>春季(76.2%) >夏季(72.9%)。不同季节BC日变化特征不同。四个季节BC日变化在2008～2013年均以单峰型分布为主,而在2016～2017年则为双峰型分布。不同季节BC的潜在来源分布存在显著区别。潜在来源高值区在2008～2010年主要分布于武汉市的西南部,范围较小;而2016～2017年主要集中在武汉市周边地区,范围变大。潜在源区的演变反映了周边城市群对武汉市BC的影响逐渐变大,这可能是造成武汉市BC质量浓度日变化的年际差异的原因。     

不同肥料种类对稻田红壤碳氮淋失的影响

土壤中碳、氮淋失降低土壤肥力,污染水体环境.为探究不同施肥种类对稻田红壤碳氮淋失影响,本试验依托中国科学院千烟洲生态站(114°53’E,26°48’N)1998年建立的红壤稻田长期定位控制试验,选用负压法采集土壤溶液,研究秸秆还田(ST)、有机肥(OM)、化肥(NPK)对土壤碳、氮淋失状况及时间动态的影响.结果表明:1稻田土壤中氮素淋失以铵态氮(NH+4-N)为主,施用NPK使土壤中NH+4-N(1.2 mg·L-1±0.1 mg·L-1)淋失最严重,施用OM使土壤中可溶解性有机碳(DOC)(27.3 mg·L-1±1.6 mg·L-1)淋失最严重,且土壤中DOC和NH+4-N均在水稻营养生长期淋失最严重(P<0.05);2施用OM与NPK可以增加稻田红壤中NH+4-N、DOC、总有机碳(SOC)和总氮(TN)含量,且施用NPK增加TN效果最显著,施用OM增加SOC最显著;3土壤渗漏液中DOC含量与稻田红壤中SOC含量呈显著正相关(P<0.01),土壤渗漏液中NH+4-N含量与稻田红壤中TN含量呈显著正相关(P<0.01).     

生物炭负载零价纳米铁去除土壤中十溴二苯乙烷

作为十溴联苯醚的替代品,新型溴代阻燃剂十溴二苯乙烷（DBDPE）已经在国内外大量使用.随着DBDPE在各种环境介质中被普遍检测到,其造成的环境污染正引起广泛关注.本论文首先制备生物炭（BC）负载零价纳米铁（nZVI）材料（BC/nZVI）,进而研究了BC/nZVI去除土壤中DBDPE的动力学过程,并探究了作用机制.结果表明：BC加入能促进nZVI均匀分散在生物炭的表面,并改善了其分散程度;BC/nZVI去除效率最高（投加量为0.1 g·g^-1,BC：nZVI为2：1,DBDPE初始浓度为10 mg·kg^-1）,24 h内达到了89.74%,去除过程涉及到吸附和降解的共同作用,实验数据符合准一级动力学方程;采用LC-MS-MS探究了DBDPE的降解产物和途径;ECOSAR毒性评价数据显示BC/nZVI能够降低DBDPE的生态毒性.     

生物炭输入对城郊农业区农田地表反照率及土壤呼吸的影响

为了探究生物炭输入对地表反照率及土壤呼吸的影响,通过田间小区试验的方法,在不同生物炭用量[0（CK）、0.5 kg·（m²·a）^-1（BC0.5）、4.5 kg·（m²·a）^-1（BC4.5）]不同地表条件下[种植作物（以+表示）、裸地（以-表示）],对农田地表反照率、土壤温湿度、土壤CO₂排放通量、土壤有机碳组分等指标进行了测定分析.结果表明,在作物生长前期（玉米的苗期至拔节期、小麦苗期至越冬期）,BC4.5+、BC0.5+的地表反照率相较CK+处理均有显著下降（P<0.05）,小麦季最大降幅分别为23.7%、17.9%,玉米季最大降幅分别为44.5%、44.9%.随叶面积指数增加,地表反照率在3个处理间的差异随之逐渐消失,作物覆盖可有效缓解生物炭输入导致的地表反照率的降低效应;裸地条件下,生物炭处理的地表反照率较对照处理在全部的观测中均有显著下降（P<0.05）;生物炭在输入初期可显著增加土壤CO₂释放量（P<0.05）,但其增幅随时间逐渐减小,其中BC4.5+较CK+的增幅从276.7%逐步降低至36.1%,BC4.5-较CK-的增幅从163.5%明显减弱至39.8%.生物炭处理较对照处理增加的CO₂释放量主要来自生物炭-土壤共存体系中的易分解碳组分,其土壤CO₂释放通量与土壤水溶性有机碳含量呈显著相关（P<0.05）;生物炭输入导致的地表反照率变化未对土壤呼吸产生直接的影响,而且生物炭输入可降低土壤呼吸温度敏感性Q10值,表明生物炭具有一定的化学和生物学稳定性.     

Observation of black carbon aerosol in Beijing,2003

The objective of this study was to determine the black carbon concentration in Beijing in 2003. The aerosol properties were measured using an Aethalometer and a tapered element oscillating microbalance (TEOM) on the roof of the Physics Building of Peking University (39.99° N, 116.31° E) from July to August 2003 and from November 2003 to January 2004. The average black carbon (BC) concentrations in the summer and winter were 8.80 and 11.4 μg/m³, respectively. During winter, two different cyclone cut offs were installed at the inlet of an aethalometer. The BC mass concentration in TSP, PM₁₀, and PM_2.5 were obtained. The results indicated that in winter aerosol, 90% of BC exited in PM₁₀ and 82.6% of BC exited in PM_2.5. The BC in PM₁₀ accounted for 5.11% of the PM₁₀ mass. Translated from Acta Scientiae Circumstantiae, 2005, 25(1): 17–22 [译自: 环境科学学报]     

CuFeO2改性生物炭对四环素的吸附特性

利用共沉淀和水热法于生物炭（BC250、BC350、BC450、BC550和BC650）负载CuFeO₂,得到的复合材料对水中四环素（TC）具有较好的去除效果.CuFeO₂与BC450质量比为2 ：1的CuFeO₂改性生物炭（CuFeO₂/BC450=2 ：1）对TC的吸附性能最强.TC于CuFeO₂/BC450=2 ：1的吸附符合颗粒内扩散模型,表明吸附是界面和孔隙扩散控制的过程.在中性pH、298 K下,CuFeO₂/BC450=2 ：1对TC的Langmuir最大吸附量为82.8 mg ·g^-1,远大于BC450的13.7 mg ·g^-1和CuFeO₂的14.8 mg ·g^-1.热力学结果表明,CuFeO₂/BC450=2 ：1对TC的吸附是自发和吸热过程.随pH增加,CuFeO₂/BC450=2 ：1对TC的吸附去除呈先增加后降低的趋势,中性条件时效果最佳.CuFeO₂/BC450=2 ：1对TC的强吸附得益于CuFeO₂负载对材料孔隙结构的改善、比表面积的增大和表面官能团、电荷属性的改变.研究结果为净化抗生素污染提供了一种高效的磁性吸附剂.     

福建省茶园土壤-茶叶的铅含量及铅同位素示踪

运用微波消解-电感耦合等离子体质谱法(ICP-MS)分析了福建省内9个市县的茶园土壤和茶叶的铅含量及铅同位素组成,评价铅污染情况并解析铅来源。结果表明,茶园土壤和茶叶的铅含量分别为23.00±0.099~55.43±0.032 mg/kg和0.53±0.126~1.47±0.058 mg/kg,地质累积指数法表明茶园土壤基本为无污染,单项因子指数法表明茶叶均为安全等级。茶园土壤和茶叶铅同位素组成具有区域性,茶叶铅同位素组成相对于茶园土壤具有较低的206Pb/207Pb和206Pb/208Pb。结合铅含量相关性分析和铅同位素示踪分析,福建省茶叶铅主要来源于茶园土壤和大气。福建省茶叶铅同位素组成的同地相似性和异地差异性特征可为茶叶产地溯源和鉴别提供一定的科学依据和参考价值。     

Contrasting factors controlling microbial respiratory activity in the sediment of two adjacent Mediterranean wetlands

Electron transport system (ETS) activity of sediments as an indication of microbial metabolic activity was examined in two adjacent Mediterranean wetlands (southern Spain). We determined the spatio-temporal variation in ETS, and we explored the potential biological [organic matter (OM), chlorophyll a (Chl a), aerobic and anaerobic bacteria] drivers of sediment ETS activity. ETS activity was notably higher in the eutrophic Lake Nueva (34.91 μl O₂ g⁻¹ D.W. h⁻¹) than in the hypertrophic Lake Honda (24.99 μl O₂ g⁻¹ D.W. h⁻¹). Strong spatial differences were observed in ETS in both study sites. Highest ETS values were achieved at the surface sediment at the deepest sampling station in each lake and a notable reduction in ETS with sediment depth was observed. By using linear regression and multiple regression analysis, OM was identified as the best predictor of ETS in Lake Honda while Chl a was the best predictor in Lake Nueva. The strong influence of OM supply on ETS activity in sediment from Lake Honda was the consequence of the labile nature of sedimentary OM, while a more refractory OM (with a higher contribution of vascular plants) comprised most of the sedimentary OM from Lake Nueva. By contrast, a large contribution of phytobenthos (supported by a higher lake water transparency) to ETS has been recognized in sediments from Lake Nueva. In summary, the results of this study revealed that the relative importance of planktonic primary producers (phytoplankton), benthic algae and vascular plants in the study sites could explain the differences observed in the intensity of sediment ETS as well as in their drivers.