6种芽苗菜微量元素的测定与比较

采用微波消解样品、电感耦合等离子发射发光法测定了红豆、绿豆、黄豆、黑豆、青豆和豌豆6种芽苗菜中的Mg、Ca、Fe、Zn、Mn、Cu、Se、Cr、As、Pb、B、Cd 12种微量元素的含量.该方法的加标回收率为93.24％-108.09％,RSD值小于3％.结果表明,6种芽苗菜中含有多种微量元素,其中Mg、Ca相对含量较高,Fe、Zn、Mn、Cu、Se、Cr含量较小,As、Se和Cd未能检测出.实验结果为芽苗菜进一步合理开发提供科学依据.     

12种饮用干花中的微量元素测定与研究

采用微波消解—电感耦合等离子体发射光谱法检测了常见12种菊科和蔷薇科饮用干花的10种微量元素含量.结果表明,花茶中含有丰富的人体必需元素Fe、Ca、Mg和Mn,具有较高的营养价值.该法用于饮用花茶品种的分析,其回收率在94.4％-113.3％之间.测定茶叶的标准物质GBW07605,结果与标准值基本一致.     

仁寿县龙泉山南端土壤Mn、B的分布特征及影响因素研究

采用ArcGIS 9.3和GPS技术对仁寿县龙泉山南端202个土壤样点耕层(0—20cm)的Mn、B含量空间分布特征及影响因素进行了研究。结果表明:龙泉山脉南端土壤中Mn含量由西向东呈先增加后降低趋势,平均含量为(169.70+62.99)mg/kg;B含量由西向东呈逐渐减少趋势,平均含量为(0.51±0.39)mg/kg;在pH各分级之间的Mn、B含量差异性分别达到极显著水平,且Mn含量与pH呈极显著正相关关系;在有机质含量各分级之间的Mn、B含量差异性分别达到极显著水平,且B含量与有机质含量呈极显著正相关关系。     

四川东部沱江乡茎瘤芥产地的地球化学特征

通过对四川省东部沱江乡茎瘤芥产区土壤的地球化学特征研究和茎瘤芥产区的土壤测试分析，并将其与全国土壤背景值比较，摸清了茎瘤芥产区土壤的元素本底特征。沱江乡茎瘤芥产区土壤Zn、Fe、Mn、Mg、K、B、P元素含量高于全国土壤平均含量，有益元素Mo、Ca、Si、Se均比全国平均值低，重金属Cr、Hg、Cd、Pb含量比全国平均值高，As元素含量则低于全国平均值水平，产区土壤中存在的Cd元素超出国家环境质量一级标准，但符合二级土壤质量标准，其他元素符合绿色蔬菜产地环境标准。     

可怜黑熊肚子上被打洞，被抽胆汗10年

据4月18日华西都市报报道，两只被“囚禁”在铁笼里天天忍受抽胆之痛的黑熊终于获得“新生”。四川双流森林公安人员在“春雷行动”中一举将这两头饱受“牢狱”之苦的黑熊解救出来，并将非法饲养、残忍虐待黑熊的养熊人罗兴贵刑拘。     

徐州云龙湖底泥重金属污染评价

本文测定了云龙湖底泥中铅(Pb)、锌(Zn)、铜(Cu)、锰(Mn)4种重金属元素含量。运用了累积指数法和潜在生态风险指数法对其污染程度和潜在生态风险进行评价:4种重金属中Cu为中度污染,Pb为轻度污染,其余2种均未构成污染。云龙湖底泥中重金属污染的潜在生态风险表现为轻微的程度,生态风险顺序是Mn>Cu>Pb>Zn。     

蓖麻（Ric inus communist L.）对锰矿区土壤中重金属累积特性的研究

为探讨蓖麻（Ricinus communist L.）对锰矿区土壤生态修复及能源化利用潜力,将不同品种蓖麻湘蓖1号和淄蓖7号播种在锰尾矿库土壤上,进入生殖生长阶段时采收全株,测定栽植土壤及植株根、茎、叶中5种重金属元素含量。结果显示：土壤中Mn平均含量最高达7884.96 mg＆#183;kg-1,超过国家规定的土壤环境质量域级标准6.5倍;湘蓖1号不同器官的Mn浓度从高至低为根＆gt;叶＆gt;茎,淄蓖7号不同器官Mn含量叶＆gt;茎＆gt;根,其叶中Mn平均浓度最高为765.43 mg＆#183;kg-1,较湘蓖1号叶中的平均含量高出79.53%, Pb、Cu、Cr含量及叶/根比值均大于湘蓖1号;植株体内重金属含量与土壤中重金属浓度的相关分析表明,重金属的积累量和转移量,受到土壤中几种重金属元素的共同影响。结果说明：2个品种的蓖麻均可以作为锰矿区能源化修复利用,对重金属的吸收和转运在品种间存在差异,淄蓖7号地上部分对重金属的迁移能力强于湘蓖1号。     

啄木鸟记者站

据4月18日华西都市报报道,两只被“囚禁”在铁笼里天天忍受抽胆之痛的黑熊终于获得“新生”。四川双流森林公安人员在“春雷行动”中一举将这两头饱受“牢狱”之苦的黑熊解救出     

大枣-豆乳复合饮料

鲜枣肉脆味美，营养丰富，VC和VP含量高，其中VC高达380～600mg／100g，糖、蛋白质和矿物质元素Fe、Ca、P等含量丰富，是一种较好的滋补物，有养胃健脾、益血壮神的功效。大豆富含植物蛋白，由大豆制成的豆乳含有大豆中大部分可溶性营养成分，必需氨基酸含量丰富，所含油脂以不饱和脂肪酸为主，且不含胆固醇，对高血压、动脉硬化等有较好的预防和治疗功效。豆乳中物质以Fe、K、P等丰富，含Ca较少；维生素以VB1、VB2、VE为主，含VA、VC较少。农业食品开发科研人员将大枣与豆乳复合，制成果味豆乳饮料，正好弥补了豆乳中VC和Ca含量…     

南京市PM_(2.5)中重金属污染特征分析及健康风险评价

自2013年12月至2014年11月,采集了南京市大气颗粒物PM_(2.5)样品共计56个,分析了As、Cd、Cr、Ni、Pb、Zn、Cu和Mn这8种重金属元素的含量及污染特征,并应用美国环保局推荐的健康风险评价模型,对其通过呼吸途径引起的人体健康风险进行了初步评价。结果表明,南京市大气PM_(2.5)质量浓度呈现明显季节特征,冬季秋季春季夏季,全年均值为86μg/m3,超我国年均二级标准的1.4倍。PM_(2.5)中8种元素浓度排序为:ZnPbMnCuCrAsNiCd,As均值超标77%,其他未超。4种致癌重金属(As、Cd、Cr、Ni)及4种非致癌重金属(Pb、Zn、Cu、Mn)中,Cr对人体健康具有很高的潜在性危害,其他7种重金属的风险可忽略,不会对暴露人群构成明显的危害。     

Soil and tree-ring chemistry response to liming in a sugar maple stand

An evaluation of the impact of dolomitic lime [CaMg(CO3)2] on soils (five years after treatment) and sapwood chemistry (after four growing seasons) was realized for a Ca-deficient sugar maple stand at the lake Clair watershed. The effect on humus chemistry was significant: exchangeable Mg and Ca, effective acidity (EA), base saturation (BSe), pH, and effective cation exchange capacity (CECe) significantly increased, while exchangeable Fe significantly decreased. In the B horizon, liming increased exchangeable Ca, Mg, and Mn concentrations while decreasing other acid cations. No significant temporal trends in element concentrations in tree rings could be detected, although the lime treatment significantly changed the average xylem Mg and Mn concentrations as well as the average Mg/Mn and Ca/Mn ratios of the sapwood. The absence of temporal trends in rings from the last 20 yr implied a significant re-equilibration of elements through the sapwood. Significant relationships were found between averaged xylem Ca/Mn and Mg/Mn ratios and exchangeable humus Ca, Mg, Mn, Al, Fe, and H+ concentration, EA, CECe, and BSe, suggesting that the average xylem Ca/Mn and Mg/Mn ratios are strong indicators of the soil acid-base status.     

Socioeconomic Factors Affecting Local Support for Black Bear Recovery Strategies

There is global interest in recovering locally extirpated carnivore species. Successful efforts to recover Louisiana black bear in Louisiana have prompted interest in recovery throughout the species’ historical range. We evaluated support for three potential black bear recovery strategies prior to public release of a black bear conservation and management plan for eastern Texas, United States. Data were collected from 1,006 residents living in proximity to potential recovery locations, particularly Big Thicket National Preserve. In addition to traditional logistic regression analysis, we used conditional probability analysis to statistically and visually evaluate probabilities of public support for potential black bear recovery strategies based on socioeconomic characteristics. Allowing black bears to repopulate the region on their own (i.e., without active reintroduction) was the recovery strategy with the greatest probability of acceptance. Recovery strategy acceptance was influenced by many socioeconomic factors. Older and long-time local residents were most likely to want to exclude black bears from the area. Concern about the problems that black bears may cause was the only variable significantly related to support or non-support across all strategies. Lack of personal knowledge about black bears was the most frequent reason for uncertainty about preferred strategy. In order to reduce local uncertainty about possible recovery strategies, we suggest that wildlife managers focus outreach efforts on providing local residents with general information about black bears, as well as information pertinent to minimizing the potential for human–black bear conflict.     

Multivariate analysis of trace metal levels in tannery effluents in relation to soil and water: a case study from Peshawar, Pakistan

Tannery effluents and relevant ground water and soil samples collected from various tanning industries of Peshawar were analyzed for Na, Ca, K, Mg, Fe, Mn, Cr, Co, Cd, Ni, Pb and Zn by the AAS method. The metal concentration data for the three media are reported in terms of basic statistical parameters, metal-to-metal correlations and linear regression analyses. Metal distributions in the three media were quite divergent and showed non-normal distributions with high standard deviation and skewness parameters. Sodium exhibited the highest mean levels of 1,277mg/L, 881mg/L and 12,912mg/kg in the effluent, ground water and soil samples, respectively. Among other metals, Cr concentrations were 410mg/L, 0.145mg/L, 100mg/kg and Ca, 278mg/L, 64.8mg/L, and 2,285mg/kg in the effluent, ground water and soil samples, respectively. Some significant correlations were observed between effluent and soils in terms of Na, Cr, Ni, Co and Pb. The ground water-soil interrelationship suggested that Na levels in the soil and ground water were significantly correlated with each other (r=0.486, P<0.01). Similarly, Cr in the soil is strongly correlated with Ca in ground water (r=0.486, P<0.01). These results were duly supported by the linear regression analysis of data. The source identification studies conducted using Principal Component Analysis (PCA) and Cluster Analysis (CA) evidenced that ground water and soil were being contaminated by the toxic metals emanating from the tannery effluents.     

Phosphorus sorption by sediments in a southeastern coastal plain in-stream wetland

A close relationship has been reported between sediment organic C (SedOC) content and its P sorption capacity (P(max)) and total P (TP) concentration. Phosphorus sorbed to organically complexed cations is a proposed explanation for this relationship. The objectives of this study were (i) to determine relationships between in-stream wetland SedOC content and both the sediment's P(max) and TP concentrations, and (ii) to ascertain the role of both organically complexed and oxalate-extractable cations on the sediment P(max) and TP values. The sediment's oxalate-extractable Fe (Fe(ox)) and Al (Al(ox)) contents were determined using acidified ammonium oxalate, while sodium pyrophosphate was used to extract organically complexed cations (Al(pryo), Ca(pyro), Fe(pyro), Mg(pyro), and Mn(pyro)). Both the sediment's P(max) and TP contents were strongly correlated with its SedOC concentration (r(2) > 0.90, P < 0.001). Only the Al(ox) contents were significantly correlated with TP and P(max), suggesting that amorphous Al forms have an important role in P sorption. All five pyrophosphate-extracted cations were significantly correlated with SedOC contents. Regression analyses showed that the Al(pyro) accounted for 88% of the variation in sediment P(max) values, whereas a combination of Al(pyro) and Ca(pyro) accounted for 98% of the variation in sediment TP concentrations. Additionally, Al and Ca chelated by SedOC compounds also have an important role in P binding and indicate that a linkage exists between the wetlands SedOC and P(max) content and its ability to accumulate TP. This study identified that two different mechanisms have significant roles in regulating P sorption by sediments in a southeastern Coastal Plain in-stream wetland.     

Combined steam-dry reforming of toluene in syngas over CaNiRu/Al2O3 catalysts

Cracking, steam reforming, dry reforming, and combined steam and dry reforming of toluene in model syngas were performed using catalysts to simulate tar removal produced during biomass gasification. The catalysts were prepared by adding Ru, Ca, and Mn to Ni-based catalysts, and their properties were measured using BET, pulse CO chemisorption, XRD and TG. In steam and dry reforming of toluene, a high toluene conversion was observed with increasing Ca content in the catalyst and catalysts containing Ca showed a higher activity than those containing Mn. In combined steam-dry reforming with syngas, 1%CaNiRu/Al₂O₃ indicated a conversion of 93.9% at 800°C.     

Bioaccumulation of metals in black mussels (Mytilus galloprovincialis) in Cape Town Harbour, South Africa

Heavy metal concentrations in black mussels (Mytilus galloprovincialis) collected from Cape Town Harbour were determined using energy dispersive X-ray fluorescence (EDXRF) and inductively coupled plasma-mass spectrometry (ICP-MS). EDXRF showed that tissue portions of the mussels contained K, Ca, Fe, Cu, Zn, Si, Sr, Al and Au, while the shell portion contained K, Ca, Fe, Cr, Zn, Si and Sr. In addition to these metals, EDXRF also revealed the presence of Al in the shells of the largest mussels. Highest concentrations of Cu and Zn were recorded in the tissues of the smallest mussels. Due to poorer detection limits of EDXRF, ultra-trace elements (Mn, Pb, As, Hg, V, Cr, Sn, Cd, Ni and Co) were determined in mussels using ICP-MS. The average metal concentrations found in the mussels are as follows; Pb (7.30 ± 0.67), Cd (1.98 ± 0.13), Hg (4.92 ± 0.60), As (6.94 ± 0.04), Sn (2.63 ± 0.13), Ni (1.88 ± 0.05), Cr (3.54 ± 0.05), V (4.17 ± 0.23), Co (0.74 ± 0.01) and Mn (35.20 ± 1.46). ANOVAs, Pearson correlation and principal component analysis (PCA) were employed in data analysis. The order of the abundance of metals in the mussels is Mn > Pb > As > Hg > V > Cr > Sn > Cd > Ni > Co. The average metal concentrations found in the mussels were higher than the permissible Food and Agriculture Organization (FAO) limits and other international guidelines.     

SEDIMENT CHEMISTRY AS INFLUENCED BY VEGETATION AND BEDROCK IN THE SOUTHWESTERN UNITED STATES1

ABSTRACT We hypothesized that sediment from small watersheds with uniform bedrock and a single vegetative community would have uniform chemical characteristics for the sand and fine (silt and clay) size fractions. Channel sediment was collected from three vegetative communities (spruce-fir, mixed conifer, and Ponderosa pine), each on four bedrock types (basalt, limestone, sandstone, and granite), and analyzed for digestable Ca, Mg, Na, K, Cu, Mn, Fe, Zn; total N and P; extractable Ca, Mg, K; cation exchange capacity; and organic matter. With the exception of organic matter content in the sand size fraction, either vegetation, bedrock, or their interaction were significant in explaining the observed variation for all analyses in both size fractions. Replicate studies of sites with similar bedrock and vegetation combinations are needed to determine if each watershed has similar or unique sediment chemistry.     

Denitrification potential and organic matter as affected by vegetation community, wetland age, and plant introduction in created wetlands

Denitrification potential (DP) and organic matter (OM) in soils were compared in three different vegetation communities-emergent macrophyte, open water, and forested edge-in two 10-yr-old created riverine wetlands. Organic matter, cold water-extractable organic matter (CWEOM), anaerobic mineralizable carbon (AnMC), and DP varied significantly (P<0.05) among vegetation communities. The surface (0 to 9 cm) soils in the emergent macrophyte community (EMC) showed highest DP (0.07+/-0.01 mg N h-1 kg-1), OM (84.90+/-5.60 g kg-1), CWEOM (1.12+/-0.20 g kg-1), and AnMC (1.50+/-0.10 mg C h-1 kg-1). In the deeper layer (9 to 18 cm), DP and CWEOM (0.04+/-0.01 mg N h-1 kg-1 and 1.13+/-0.20 g kg-1, respectively) were significantly higher in the open water community (OWC) than in the emergent macrophyte and forested edge communities. Plant introduction did not affect DP or OM content and characteristics. After 10 yr of wetland development, mean DP increased 25-fold in the surface layer (from 0.002 to 0.053 mg N h-1 kg-1); OM content more than doubled to 90.80+/-19.22 g kg-1, and CWEOM and HWEOM increased 2.5 and 2.7 times respectively from 1993 (prewetland conditions) to 2004. Humic acids were the most abundant form of OM in 2004 and 1993 samples. Significant (P<0.05) positive relationships between DP and OM, CWEOM, and AnMC were found in the surface layer; in the 9- to 18-cm layer, significant positive relationships were found between DP and CWEOM and AnMC.     

Predicting runoff of suspended solids and particulate phosphorus for selected Louisiana soils using simple soil tests

This study was conducted to evaluate the relationships among total suspended solids (TSS) and particulate phosphorus (PP) in runoff and selected soil properties. Nine Louisiana soils were subjected to simulated rainfall events, and runoff collected and analyzed for various parameters. A highly significant relationship existed between runoff TSS and runoff turbidity. Both runoff TSS and turbidity were also significantly related to runoff PP, which on average accounted for more than 98% of total P (TP) in the runoff. Runoff TSS was closely and positively related to soil clay content in an exponential fashion (y=0.10e0.01x, R2=0.91, P<0.001) while it was inversely related to soil electrical conductivity (EC) (y=0.02 x(-3.95), R2=0.70, P<0.01). A newly-devised laboratory test, termed "soil suspension turbidity" (SST) which measures turbidity in a 1:200 soil/water suspension, exhibited highly significant linear relationships with runoff TSS (y=0.06x-4.38, R2=0.82, P<0.001) and PP (y=0.04x+2.68, R2=0.85, P<0.001). In addition, SST alone yielded similar R2 value to that of combining soil clay content and EC in a multiple regression, suggesting that SST was able to account for the integrated effect of clay content and electrolytic background on runoff TSS. The SST test could be used for assessment and management of sediment and particulate nutrient losses in surface runoff.     

Major and trace elements of selected pedons in the USA

Few studies of soil geochemistry over large geographic areas exist, especially studies encompassing data from major pedogenic horizons that evaluate both native concentrations of elements and anthropogenically contaminated soils. In this study, pedons (n = 486) were analyzed for trace (Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Zn) and major (Al, Ca, Fe, K, Mg, Na, P, Si, Ti, Zr) elements, as well as other soil properties. The objectives were to (i) determine the concentration range of selected elements in a variety of U.S. soils with and without known anthropogenic additions, (ii) illustrate the association of elemental source and content by assessing trace elemental content for several selected pedons, and (iii) evaluate relationships among and between elements and other soil properties. Trace element concentrations in the non-anthropogenic dataset (NAD) were in the order Mn > (Zn, Cr, Ni, Cu) > (Pb, Co) > (Cd, Hg), with greatest mean total concentrations for the Andisol order. Geometric means by horizon indicate that trace elements are concentrated in surface and/or B horizons over C horizons. Median values for trace elements are significantly higher in surface horizons of the anthropogenic dataset (AD) over the NAD. Total Al, Fe, cation exchange capacity (CEC), organic C, pH, and clay exhibit significant correlations (0.56, 0.74, 0.50, 0.31, 0.16, and 0.30, respectively) with total trace element concentrations of all horizons of the NAD. Manganese shows the best inter-element correlation (0.33) with these associated total concentrations. Total Fe has one of the strongest relationships, explaining 55 and 30% of the variation in total trace element concentrations for all horizons in the NAD and AD, respectively.