广州市蔬菜地重金属剂量对蔬菜富集重金属的影响--以菜心为例

调查并分析了广州市蔬菜地土壤和菜心中主要重金属元素质量分数，通过多元统计分析建立了菜心中某一重金属元素和土壤中元素的数学回归模型。结果表明，Cd更易在菜心体内造成累积；总体上菜心中重金属质量分数与其在土壤中的质量分数有一定的相关性，菜心中Pb、As的积累分别取决于土壤中Pb、As的质量分数，土壤中Pb和As还分别促进了菜心对Cr、Hg的吸收，Pb对菜心中Cd的累积表现为协同作用；土壤重金属质量分数临界值可为今后无污染蔬菜的生产提供参考依据。     

天津市土壤风沙尘元素的分布特征和来源研究

通过与土壤标准和背景值的比较分析了天津市土壤风沙尘元素的质量分数分布特征，通过富集因子法分析了天津市风沙尘元素的富集特征，进而说明天津市风沙尘元素的来源及其变化。结果表明，（1）Cr、Ni、Cu、Zn和As质量分数均有超过土壤标准的现象。（2）Ni、Cu、Pb、Zn和Ag超过背景值10倍以上，受到了人为污染。（3）粗颗粒中西青区的Pb元素，津南区的Ni元素和Pb元素以及细颗粒中东丽区的Ca元素和Zn元素，西青区的Cu、Pb，津南区的Cr、Ni、Pb等元素达到显著污染级别；各区粗细颗粒中的Ag元素污染级别最高，有的为极强烈污染；这些元素是典型的人为污染元素。（4）粗颗粒中只有Ca和Ni污染级别有所增加，细颗粒中只有Na、Ni、As等3种元素的富集因子略有增加。所以，天津市土壤风沙尘的治理重在控制人为来源的Ni、Cu、Pb、Zn、Ag、Cr和Ca等高污染元素。     

柠檬酸对土壤养分的活化及对作物吸收Fe、P的影响

土壤pH值是影响石灰性土壤Fe、Zn、Mn等微量元素有效性的重要因素，利用土壤培养法，研究了不同浓度柠檬酸溶液对石灰性土壤的pH值以及对P、Fe、Mn、Zn等元素的活化效应。结果表明，浓度高于0．001mol／L的柠檬酸溶液培养土壤，可降低土壤pH值，增加土壤有效P、Fe、Mn、Zn等元素的质量分数。培养24h后，P、Fe、Mn、Zn等有效养分质量分数最高，随着培养时间的延长，有效养分的质量分数下降，活化效果减弱，土壤表现出一定的钝化效应。利用盆栽模拟滴灌施肥条件，柠檬酸溶液处理可显著促进花生、菜豆植株的生长，叶片SPAD读数增加，并提高植株对P、Fe元素的吸收量，因此滴灌施肥条件下，可考虑使用柠檬酸增加石灰性土壤根区微量元素的有效性。     

天津污灌区土壤重金属污染环境质量与环境效应

污水作为天津解决农业用水不足的手段已经有几十年的历史。文章分析了污灌区土壤一作物系统中Cd、Hg、As、Cu、Pb、Zn和Cr等有毒重金属的质量分数，利用单因子污染指数法和加权综合污染指数法进行污染评价。评价结果表明污灌区土壤受到了严重污染，主要重金属污染元素为Cd、Hg；农作物中的主要超标元素为Cd、As。因此，污灌区重金属污染土壤的修复工作迫在眉睫。     

北京市水溶肥料重金属元素分析与评价

研究分析北京地区水溶肥料中的重金属元素,为农产品质量安全生产提供基础依据.对2012—2019年水溶肥料样品中Hg、As、Pb、Cr和Cd等有害元素进行调查统计,参照中国农业行业标准和内梅罗综合污染指数法进行分析与污染评价.结果表明,水溶肥料中Hg、As、Pb、Cr和Cd平均质量分数分别为0.04、3.8、3.9、4....     

癌症与土壤环境中Sn元素的关系

利用土壤环境资料中关于锡元素的32335个数据,癌死亡调查资料787080例,研究了胃癌、食管癌、肝癌、宫颈癌、肺癌、大肠癌、白血病、鼻咽癌、乳腺病死亡率与人鲜生活区土壤环境中锡元素的关系,结果表明。食管癌死亡率与生活区土壤中锡元素质量分数的相关性显著,肝癌、宫颈癌、鼻咽癌死亡率与生活区土壤中锻元素质量分数的相关性极显著,而胃癌、肺癌、大肠癌、白血病、乳腺癌死亡率与生活区土壤中锡元素质量分数的相共性下显著。     

野生及养殖背角无齿蚌中元素的生物积累特征

作为建立渔业生态环境“淡水贝类观察”体系的基础研究之一,以宜兴养殖水域（N=7）和太湖三山岛自然水域（N=7）采集的背角无齿蚌（Anodonta woodiana）为对象,运用电感耦合等离子质谱仪测定了背角无齿蚌软组织中元素Na、K、Ca、Mg、Mn、Fe、Co、Ni、Se、Cu、Cr、Cd的质量分数范围,并对各种元素积累水平的差异进行比较研究。结果表明,两水域中背角无齿蚌对元素的积累高低顺序具有相似的趋势。其中Ca质量分数最高,Co、Cr的质量分数最低,其它元素界于其间。养殖蚌样中的常量元素Na、K、Ca、Mg和微量元素Mn、Co的积累质量分数高于或接近自然水域蚌样中的相应元素,但后者中的重金属元素Cr、Cu、Cd、Ni质量分数显著地高于前者。养殖水域蚌样中的Mg-K、Mg-Ca、Mg-Ni、Mg-Mn、K-Ca、K—Co、K．Mn、Ca—Co、Ca—Ni、Ca．Mn、Ni—Mn、Cr-Co、Cu-Cd以及自然水域蚌样中的Mg—K、Ca-Cr、Ca—Mn、Ca-Ni、Ca-Cd、Cr—Mn、Cr-Ni、Cr-Cd质量分数之间呈现显著的相关性。     

煤中痕量元素与三态硫关系的模型

将青山烟煤按不同比重分级后，分别测定了各级煤粉中痕量元素Ｂｅ、Ｃｄ、Ｐｂ、Ｃｏ，Ｃｒ，Ｃｕ，Ｎｉ，Ａｓ以及三态硫的含量，发现痕量元素与三态硫之间有一定的相关关系，本文用回归分析法建立了痕量元素与三态硫关系的模型，并用该模型对青山烟煤某一比重范围内煤粉中的痕量元素含量进行预报，结果令人满意。     

鼻咽癌与土壤环境中化学元素的相关性研究

利用土壤元素数据２０６９４４８个,鼻咽癌死亡调查资料２２５６０例,研究了鼻咽癌死亡率与土壤环境中６１个元素质量分数的相关性。结果表明,汞、铅、硒、针、锡、钛、钽、溴、碘元素质量分数与鼻咽癌死亡率呈非常显著的正相关;铪元素质量分数与鼻咽癌死亡率呈显著的正相关;铟、镱、镥、铀、锆、铋、碲元素质量分数与鼻咽癌死亡率呈较显著的正相关。锰、钠、镁、钙、锶元素质量分数与鼻咽癌死亡率呈非常显著的负相关;钾、钡元素质量分数与鼻咽癌死亡率呈较显著的负相关。钒、铷、铯、银、铝、镓、铊、钪、钇、镧、铈、钕、钆、镝、钬、铒、铥、钼、钨、铁、砷、镉、钴、铬、铜、氟、镍、锌、锂、铍、硼、镨、钐、铕、铽、锗、锑元素质量分数与鼻咽癌死亡率无明显的相关性。     

典型西北钢铁城市冬季大气颗粒物重金属来源解析及健康风险评价——以嘉峪关为例

为研究嘉峪关市冬季PM_2.5,PM₁₀中重金属来源并对其健康风险进行评估,于2019年12月18日—2020年1月16日进行PM_2.5,PM₁₀样品的采集,并利用电感耦合等离子体质谱法（ICP-MS）对16种金属及无机元素（Mg、Al、Ca、Fe、V、Cr、Mn、Co、Ni、Cu、Zn、As、Se、Cd、Ba、Pb）进行质量浓度的分析;通过富集因子及主成分分析法对16种金属及无机元素的来源进行解析;用EPA的健康风险评估模型对Cr、Ni、As、Co、Cd、Cu、Mn、Zn、Pb、V等10种元素进行健康风险评价.结果表明,PM_2.5与PM₁₀中质量浓度较高的元素为Mg、Al、Ca、Fe等4种地壳元素,其余12种元素的浓度相对较低;Se、Cd、Pb、Zn、Mg等5种元素在PM_2.5与PM₁₀中的富集因子值均大于10,其中Cd元素在PM_2.5与PM₁₀中的富集因子值最大,分别...     

春、夏季长江口海域营养盐的时空分布特征及营养结构分析

2009年春季（5月）和夏季（8月）分别对长江口海水中的营养盐（DIN、SiO32--Si、PO43--P）进行调查,分析其时空分布特征,探讨其影响机理,并对富营养化水平进行了评价。结果表明：春、夏季表、底层DIN、SiO32--Si的平面分布有从近岸向离岸逐渐降低的特点,而PO43--P则表现出一种缓冲现象;各营养盐在表、底层的质量浓度春季均小于夏季,且DIN的主要存在形式均为NO3-_N;DIN、SiO32--Si主要来源于径流输入,PO43--P则有多种来源。春、夏季表、底层SiO32--Si/PO43--P、DIN/PO43--P均远大于Redfield值,具有营养盐比例不平衡的特征,且DIN/PO43--P、SiO32--Si/DIN、SiO32--Si/PO43--P在长江口海域的分布不均匀;从浮游植物吸收DIN/PO43--P的配比分析,PO43--P是春、夏季长江口海域潜在性营养限制因子;春、夏季E值均远大于富营养化阀值,该海域富营养化现象严重。     

黄花菜高产、优质栽培与加工技术

黄花菜以花蕾食用,是一种营养十分丰富的蔬菜,含有人体需要的蛋白质、维生素、多糖、钙、铁、磷等多种元素成分,是很受人们欢迎的绿色健康食品,衡阳市现种植面积达20万亩,还在逐年扩大,发展前景非常广阔．为了提高黄花菜产量和品质．本文提出了黄花菜高产,优质栽培与加工技术．表2,参5．     

物种敏感度分布的非参数核密度估计模型

针对目前物种敏感度分布参数方法建模所存在的缺点,首次提出基于非参数核密度估计方法的物种敏感度分布模型,并提出相应的最优窗宽和检验方法。选用无机汞作为案例研究对象,利用非参数核密度估计方法和3种传统参数模型分别推导了保护我国水生生物的无机汞的急性水质基准值。结果表明,非参数核密度估计方法在推导无机汞水质基准中的稳健性和精确度都大大优于传统参数模型,能够更好地构建物种敏感度分布曲线。该方法的提出丰富了水质基准的理论方法学,为更好地保护水生生物提供了有力的支撑。     

Influence of habitat quality, population size, patch size, and connectivity on patch-occupancy dynamics of the middle spotted woodpecker

Despite extensive research on the effects of habitat fragmentation, the ecological mechanisms underlying colonization and extinction processes are poorly known, but knowledge of these mechanisms is essential to understanding the distribution and persistence of populations in fragmented habitats. We examined these mechanisms through multiseason occupancy models that elucidated patch-occupancy dynamics of Middle Spotted Woodpeckers (Dendrocopos medius) in northwestern Spain. The number of occupied patches was relatively stable from 2000 to 2010 (15-24% of 101 patches occupied every year) because extinction was balanced by recolonization. Larger and higher quality patches (i.e., higher density of oaks >37 cm dbh [diameter at breast height]) were more likely to be occupied. Habitat quality (i.e., density of large oaks) explained more variation in patch colonization and extinction than did patch size and connectivity, which were both weakly associated with probabilities of turnover. Patches of higher quality were more likely to be colonized than patches of lower quality. Populations in high-quality patches were less likely to become extinct. In addition, extinction in a patch was strongly associated with local population size but not with patch size, which means the latter may not be a good surrogate of population size in assessments of extinction probability. Our results suggest that habitat quality may be a primary driver of patch-occupancy dynamics and may increase the accuracy of models of population survival. We encourage comparisons of competing models that assess occupancy, colonization, and extinction probabilities in a single analytical framework (e.g., dynamic occupancy models) so as to shed light on the association of habitat quality and patch geometry with colonization and extinction processes in different settings and species.     

太湖浮游植物群落结构及其与水质指标间的关系

为了探讨太湖浮游植物群落结构时空分布特征、以及太湖浮游植物群落指标与水质指标间的关系,于2013年1月─2013年12月对太湖7个点位浮游植物群落结构和水质指标（水温、透明度、pH、溶解氧、电导率、总氮、总磷、氨氮、高锰酸盐指数、化学需氧量、氟化物、生化需氧量、硝酸盐氮、亚硝酸盐氮、溶解性磷酸盐和叶绿素a）进行月度调查,研究其浮游植物群落结构和湖泊水质的时空分布;并利用Pearson相关性分析浮游植物密度、浮游植物多样性与水质指标间的关系;找出影响太湖浮游植物群落结构的主要水质指标。结果表明：太湖7个点位共获得124种浮游植物物种,其中蓝藻门（Cyanophyta）30种、绿藻门（Bacillariophyta）47种、硅藻门（Chlorophyta）34种、隐藻门（Cryptophyta）3种、裸藻门（Euglenophyta）6种和甲藻门（Dinoflagellate）4种;其中蓝藻门的微囊藻属（Microcystis spp.）为绝对优势种群,优势度为80.8%;太湖浮游植物总密度与蓝藻门密度呈极显著正相关（r=1.000,P＜0.0001）;绿藻门和硅藻门占浮游植物总密度百分比分别和蓝藻门占浮游植物总密度百分比呈极显著负相关（r=-0.497,P＜0.0001;r=-0.814,P＜0.0001）。太湖7个点位水质首要污染物为总氮,其次是总磷和化学需氧量;西太湖污染物浓度最高。从空间上看,太湖浮游植物总密度最高值出现在贡湖湾（远离其入湖口处）,且贡湖湾浮游植物群落多样性相对低于太湖其他点位,同时贡湖湾微囊藻属密度百分比达90.1%,远高于太湖其他点位;从时间上看,太湖浮游植物总密度最高值出现在12月份、其次是6月份;通过浮游植物群落指标与水质指标相关性分析,水温、透明度、总氮、化学需氧量、叶绿素a是影响太湖浮游植物群落结构的主要水质指标。控制太湖入湖口水质污染物浓度排放和修?     

井冈山两种典型森林土壤有机碳密度及其影响因素的比较

森林土壤有机碳是土壤有机碳库的重要组成部分,研究森林土壤有机碳及其影响因素对于应对气候变化具有非常重要意义。以井冈山自然保护区两种典型森林类型（常绿阔叶林和人工杉木林）为研究对象,各选取12个样地,对比分析了两种森林土壤有机碳密度的垂直分布特征以及与年均温、年降雨量之间的相关性。结果表明：①常绿阔叶林0-100cm层平均土壤有机碳密度为（25．65±3,27）kg-^2,大于人工杉木林0-100cm层平均土壤有机碳密度为（20．37±3．37）kg·m^2;②常绿阔叶林和人工杉木林土壤有机碳密度均随土壤深度的增加显著减少;③常绿阔叶林与人工杉木林土壤有机碳密度随年均温的变化趋势差异较明显,常绿阔叶林0-100cm层土壤有机碳密度随年均温的上升呈显著增加趋势（P〈0．05）,而人工杉木林随年均温的上升先减小后增加再减小,且变化趋势显著（P〈0．05）;④常绿阔叶林与人工杉木林土壤有机碳密度随年降雨量的变化趋势差异亦明显,常绿阔叶林0-100cm层土壤有机碳密度随年降雨量的增加呈显著减小趋势（P〈O．05）,而人工杉木林随年降雨量的增加先增加后减少再增加,且变化趋势极显著（P〈0．005）;⑤森林土壤有机碳质量分数与土壤容重呈极显著负相关（P〈0．0001）。     

Distribution and abundance of finless porpoise in the Inland Sea of Japan

Aerial sighting surveys were conducted in 2000 to evaluate the distribution and abundance of finless porpoise Neophocaena phocaenoides in the Inland Sea of Japan. We flew 60 north–south transects (2,218 km in total) at intervals of 6.43 km over the study area between 131°3′ and 134°59′ E. In total, 148 groups were detected by two observers. The average group size was 1.56 individuals. The effective strip half-width of each observer was estimated to be 107 m (coefficient of variation [CV] = 8.26%). Porpoise abundance was estimated at 7,572 individuals and the density was as low as 0.506 individuals/km² (CV = 17.3%). The sea is among the Japanese waters with the lowest density in spite of its favorable topographical conditions. In the western stratum of the study area, where the estimated density was 1.31 individuals/km², we observed a relatively regular distribution. In the central-eastern stratum, which had an estimated density of 0.208 individuals/km², we confirmed a clumped distribution that was restricted to inshore waters or near islands. No individuals were observed in waters between 132°51′ and 133°11′E, and between 133°43′ and 133°59′E, where sand dredging and other human activities have been active, suggesting that habitat fragmentation has occurred.     

Anchovy (<Emphasis Type="Italic">Engraulis encrasicolus</Emphasis>) egg density measurements in the Bay of Biscay: evidence for the spatial variation in egg density with sea surface salinity

Knowledge of the pelagic vertical distribution of fish eggs is central for several aspects of fisheries science including fisheries recruitment and egg production studies. In modelling egg vertical distributions, variation in fish egg density is an important issue. Though variation in egg density between individual eggs has been reported, evidence for significant spatial variation in egg density is novel. The present study provides evidence that egg density of anchovy (Engraulis encrasicolus) varies spatially across spawning sites in the Bay of Biscay, depending on the regional scale variation in sea water properties due to river discharge. We measured the density of the eggs using a density gradient column at 17 stations in 2005 and 2006 as well as their diameter. At station, the variability in the individual egg density was statistically distributed according to a Gaussian probability function. Significant variation in the mean egg density was observed across stations. Mean egg density displayed a significant correlation with sea surface salinity. Results are discussed in light of the mechanisms determining the egg density.     

电感耦合等离子体-质谱法研究大气颗粒物中元素浓度

1　IntroductionAirborneparticulatematterisoneoftheimportantmarkersofairqualityandisanimportanthealthconcerninurbanareas,especiallywithrespecttoanumberofchronicrespiratorydiseases.Medicaldatasuggeststhatitisthisfractionofparticulatematterthatbecomesdeeplyi…     

Responses of a bacterial pathogen to phosphorus limitation of its aquatic invertebrate host

Host nutrition is thought to affect the establishment, persistence, and severity of pathogenic infections. Nutrient-deficient foods possibly benefit pathogens by constraining host immune function or benefit hosts by limiting parasite growth and reproduction. However, the effects of poor elemental food quality on a host's susceptibility to infection and disease have received little study. Here we show that the bacterial microparasite Pasteuria ramosa is affected by the elemental nutrition of its aquatic invertebrate host, Daphnia magna. We found that high food carbon:phosphorus (C:P) ratios significantly reduced infection rates of Pasteuria in Daphnia and led to lower within-host pathogen multiplication. In addition, greater virulent effects of bacterial infection on host reproduction were found in Daphnia-consuming P-deficient food. Poor Daphnia elemental nutrition thus reduced the growth and reproduction of its bacterial parasite, Pasteuria. The effects of poor host nutrition on the pathogen were further evidenced by Pasteuria's greater inhibition of reproduction in P-limited Daphnia. Our results provide strong evidence that elemental food quality can significantly influence the incidence and intensity of infectious disease in invertebrate hosts.