环境氟迁移与茶叶氟富集的关系

选择３种类型茶场进行大气氟污染与茶叶氟富集的现场监测与研究,对苏南茶区１１个茶场的土壤总氟、水溶性氟和茶叶氟富集量进行了测定。结果表明：茶叶氟富集量与来自砖瓦窑厂的大气氟污染浓度呈现高度的正相关,与土壤含氟量不呈现相关;茶树是高富集氟的植物,富集能力远高于一般植物,氟富集量可达每千克数十至数百毫克。茶叶的氟富集与氟污染应引起重视     

土壤中镉、铅、锌及其相互作用对作物的影响

通过作物盆栽模拟试验(砂壤质褐土、pH值8.2)揭示：土壤中分别施入镉(CdCl2)、铅[Pb(CH3COO)2]或锌(ZnSO4)其影响表现为,植物各器官镉的含量超过对照植物的数倍至500倍。土壤镉浓度<5ppm和<10ppm分别造成某些蔬菜和水稻的污染。铅主要积累在植物根部,土壤铅污染对作物的影响较小。锌主要积累在植物叶片和根部,对水稻产生生长抑制的土壤锌浓度临界值不大于200ppm,此浓度对旱作无影响。土壤中同时施入镉和铅,植物对镉的吸收增加。而土壤中镉的增加却减少了植物体内铅的含量。土壤中由于镉、锌或铅、锌相互作用的结果,水稻对它们的吸收都有增加。在旱地土壤锌浓度的增高,降低了植物对镉、铅的吸收。镉、铅、锌同时施入土壤由于相互作用的结果,除锌之外,植物对镉、铅的吸收有明显下降。评价土壤重金属污染,不仅要看它们的含量及其存在形态,而且要分析它们之间的相互作用(促进或拮抗)特点。     

木本植物对大气重金属污染物耐性的研究

本文在污染现场调查研究、试验研究和单一毒物接触试验的大量数据基础上,论述了木本植物对大气重金属污染物一一铅、镉、铜、锌的耐性。查明了大气重金属污染物引起叶片可见伤害症状需要很高的剂量。糖槭以2000ppm硝酸铅溶液浸泡涂抹枝叶,三天后出现轻度可见伤害症状,叶中铅积累量高达802ppm。旱柳以500ppm氯化镉溶液浸泡涂抹枝叶,叶中积累量达66ppm,十天内未出现可见症状。大气重金属污染物——铅、镉、铜、锌对叶片造成的急性伤害症状是相似的,而与土壤中相同污染物引起的急性伤害具有差别。木本植物对大气重金属污染物的耐性很强,在以大气重金属污染为主的复合污染现场,一些幼龄树木的叶片吸铅量达500—800ppm,超过背景浓度的120倍;吸镉量10—18ppm,超过背景浓度的139倍,吸铜量100—239ppm,超过背景浓度的5—12倍,吸锌量500—700ppm,超过背景浓度的9—20倍只出现较轻的受害症状。在相对清洁区,对幼树叶片进行单一毒物接触试验,一些主要绿化树木的叶片吸铅量达200—600ppm,吸镉量20—60ppm并不出现可见症状。木本植物对大气重金属污染物具有较强的耐性,因而为生物防治大气重金属污染开辟了广阔的前景。     

大气氟污染对达乌尔黄鼠及其环境的影响

本文研究大气氟污染对达乌尔黄鼠及其环境的影响。研究区内的钢厂为大气氟污染的点源。在研究区内选6个取样点,分别取黄鼠大腿骨骨样、植物样和土样。 黄鼠大腿骨骨灰、植物和土壤的含氟量是随与污染源的距离和方向的不同而变化的,离污染源愈远各样品的含氟量愈低。污染源西北方向,靠近污染源的取样点污染特别严重。但是,黄鼠体重与其大腿骨骨灰含氟量间没有明显相关。黄鼠可认为是对氟污染的“耐干扰种”。 在研究区内,氟污染对植物群落的种类、生物量和群落的多样性没有明显地影响。大腿骨骨灰和植物含氟量间存在一定的回归关系,其关系式为Y=27.16X~1.02。     

内蒙古典型草原区四种主要物种的植物-土壤反馈作用

植物-土壤反馈对解释群落组成变化和预测群落动态具有重要意义,是群落生态学与恢复生态学研究的热点领域。本研究以内蒙古典型草原区4种主要物种羊草(Leymus chinensis)、大针茅(Stipa grandis)、克氏针茅(Stipa krylovii)和冰草(Agropyron cristatum)为研究对象,采用植物-土壤反馈研究的两阶段法进行盆栽实验,研究了单种种植植物对土壤的影响(所得土壤用S-植物种拉丁名首字母表示,分别为S-Lc、S-Sg、S-Sk、S-Ac),以及这些受影响土壤对后续种植植物个体水平和群落水平的植物-土壤反馈作用。结果表明:(1)4种植物单种后对土壤C∶N、速效磷含量以及p H值3个指标具有显著影响(P0.05);(2)个体水平的植物-土壤反馈具有物种特异性,羊草和冰草的分蘖数、株高、地上部生物量、地下部生物量以及总生物量5个观测指标的最高值均出现在S-Sk;克氏针茅5个观测指标的最高值出现在S-Lc;大针茅分蘖数和株高的最高值出现在S-Ac,而生物量的最高值出现在SLc;(3)大针茅和克氏针茅的反馈效应值(FV)显著小于0,表现为负反馈;冰草表现为中性反馈;羊草表现为中性至弱正反馈;(4)4种物种两两间净配对反馈值(I)均为负值,且克氏针茅-羊草以及克氏针茅-冰草间反馈值显著小于0,表明这些物种两两间能稳定共存。这些结果为内蒙古草原区植物群落组成变化对地下部土壤、后续植物的生长状况以及主要物种种间关系的影响的预测提供了实验数据。     

粤东铅锌尾矿区四种莎草的重金属富集特性研究

从梅州丙村铅锌尾矿区近污水排放区采集了土壤与四种优势植物样品, 分别测定和分析了Zn、Pb、Ni、Cu、Cr、Cd、Mn 七种重金属含量。结果表明, 该矿区土壤污染严重且为强酸性。Cd、Pb、Zn、Mn、Cu 的污染指数均大于3, 且综合污染指数为319.16, Zn、Pb、Cd 均超出国家土壤环境质量(GB15618-1995)的二级标准, 也远超过广东土壤背景值, 有很大的潜在生态风险, 重金属单因子生态风险指数大小排序为Cd>Pb>Zn>Mn>Cu>Ni>Cr。两歧飘拂草(Fimbristylis dichotoma)、细辐射枝藨草(Scirpus filipes)、多枝扁莎(Pycreus polystachyus)地下部分的Pb 含量均超过超富集植物临界含量标准, 因此这三种植物有作为Pb 富集植物的潜力。贝壳叶荸荠(Heleocharis chaetaria)对镍的富集系数超过1, 细辐射枝藨草对Mn 的转移系数大于1。这四种植物对土壤的重金属污染有很强的耐性, 与非矿区土壤中生长相比, 长势并无显著差异, 且地下部分重金属含量都很高, 说明对它们土壤中的重金属有一定的固定作用, 可作为这些区域植被恢复的先锋植物。     

土壤氟形态与氟污染土壤修复

我国土壤氟污染问题严峻,给部分地区人体健康和生态安全造成严重威胁,但土壤氟污染与防治问题仍没有受到人们的广泛关注.本文概述了土壤中氟的存在形态以及发生的主要化学反应,综述了近年来国内外有关氟污染土壤修复的研究进展,提出了今后氟污染土壤修复的研究方向,以期为氟污染土壤的修复提供借鉴和参考.土壤中氟主要分为5种形态,其中90%以上以残渣态存在,土壤溶液中的氟主要发生沉淀-溶解、络合-解离和吸附-解吸等反应来维持水-土系统中的氟平衡.目前,氟污染土壤修复技术研究主要集中在化学固定修复技术、化学淋洗技术、电动修复技术以及植物修复技术.今后需要重点研究氟在土壤中的赋存形态及其影响因子,筛选功能微生物和植物,开发联合修复技术以修复氟污染土壤.     

锌污染对植物的毒害及植物的忍耐性

锌在土壤中的总含量一般为10—300ppm,个别土壤可达500—1000ppm;在一些铅、锌矿区土壤的含锌量可高达2800ppm,甚至更高。锌是植物生长发育的必需元素,但环境中过量的锌会造成环境污染,使一些植物受害不能生存,一些植物可     

砷对农田生态系统污染效应的试验研究

本文通过盆栽及模拟试验,研究了砷对农田生态系统中农作物、土壤微生物、土壤动物的污染效应。结果表明,砷对农作物生长发育有明显不良影响,浓度过高,产量下降并造成农作物体内砷的残留累积;不同种类农作物对砷的敏感程度不同,以对水稻的危害最严重,其次为春小麦、玉米;不同形态砷化物的污染效应有显著差别,亚砷酸盐的毒性最强,砷酸盐次之,硫化砷的影响最小。 砷对土壤微生物具有明显抑制作用,使土壤细菌总数降低,投加亚砷酸钠5ppm,砷酸氢二钠10ppm时,细菌总数开始减少。对土壤固氮菌、解磷细菌、纤维分解细菌等土壤有益微生物有明显抑制作用,使存活率下降。砷污染土壤活性降低,土壤呼吸强度下降。 砷污染影响土壤中蚯蚓的数量与分布,当砷在100—300ppm时,可使蚯蚓致死,死亡率达50—80％。砷在蚯蚓体内明显富集,富集系数为1.32—7.44。     

青海锡铁山矿区铅、锌的植物地球化学特征及其与矿的关系

 通过青海锡铁山铅、锌矿区植物群落和植物中铅,锌含量特征的调查研究表明：该区植被为荒漠植被类型。矿带上的植物群落与非矿带上的相比较,群落中种属数目更少,覆盖度更低,植物生长更低矮。植物灰分中的锌含量(平均)为125.9—1144ppm。膜果麻黄(Ephedra przewalskii)含量最高,变化范围最大,为86.11—5871.88ppm。植物中的铅含量为31.32—1129.6ppm。黑柴(Sympegma regelii)含量较高,变化最大,平均为746ppm,极值为14.3—5561.70ppm。在矿带上含量最高,非矿带对照区含量最低。植物及其生长的土壤中金属元素含量之间的关系,无论是铅还是锌含量都有很好的线性关系。膜果麻黄、黑柴、优若藜(Eurotia ceratoides)和中亚紫菀木(Asterothamnus centrali-asiaticus)等植物相关系数均达显著相关水平(α≤0.05)。 这在植物地球化学勘探上是非常有用的。例如中亚紫菀木和琵琶柴(Reaumuria soongorica)中铅的植物地球化学异常,准确地圈出了铅、锌矿的位置,衬度高,异常范围与矿化区基本吻合。     

Combined effects of air and soil pollution by fluoride emissions on Tibouchina pulchra Cogn., at Cubatão,SE Brazil,and their relations with aluminium

High deposition of gaseous/particulate fluorides and other air pollutants has resulted in an acidification and probable formation of soluble AlF_x complexes in the soil in the vicinity of the industrial complex of Cubatão, SE Brazil. With the present field study we aimed at determining the contribution of F and Al uptake from fluoride-contaminated soil, supposedly as AlF_x complexes, to the increase of foliar F and Al contents in saplings of an Al-accumulator tree species (Tibouchina pulchra) which were concomitantly exposed to fluoride-contaminated air and also the proportional contribution of both air and soil contamination to the mentioned foliar accumulation of these elements. The seasonal variations in F and Al accumulation and possible metabolic changes in the plants due to F and Al accumulation were also investigated. The saplings were exposed during three consecutive periods of 16 weeks to: (a) air and soil from a reference site (PV_noF); (b) air or soil from two polluted sites (CM-high air pollution, low F and MV-high air pollution, high F); and (c) both air and soil from these polluted sites. After exposure, the changes in the foliar concentrations of F and Al, the relations between both element contents and their relationships with oxidative stress indicators were determined. The data were grouped in three matrices: PV_noF–CM_lwF and PV_noF–MV_hgF, taking in account the possible air/soil exposure combinations in each, and soil/air from all sites. The slight F accumulation in plants of PV_noF–CM_lwF matrix was a result of higher uptake from soil than from air (54 and 46%, respectively). At PV_noF–MV_hgF matrix, the extremely high F accumulation in leaves of T. pulchra could be attributed to the combination of both air and soil contamination (83 and 17%, respectively). T. pulchra always showed higher foliar Al concentrations than 1000 g g^–1 dry mass, mainly after exposure to air and soil of both polluted sites (CM_lwF and MV_hgF). A highly significant linear regression was estimated between molar Al and F contents, taking in account the data obtained for saplings of T. pulchra cultivated in the different soils and exposed to ambient air of PV_noF, suggesting that both elements were taken as Al–F complexes from soil. The uptake of fluorides from air and/or soil of MV_hgF caused significant metabolic changes in T. pulchra, but visible injury supposedly induced by fluorides were observed only when the foliar F contents surpassed 700 g g^–1 dry mass. On the contrary, Al did not cause any metabolic stress to the plants.     

天津汉沽农田土壤－植物系统中汞的分布、迁移和积累

本文研究了受汞污染的农田土壤—植物系统中汞的分布,迁移和积累的规律。土壤中的汞在离污染源3公里的范围内含量最高;主要集中在0一20厘米的土壤上层,几乎不往下迁移。植物可以从土壤和大气中吸收、积累汞。在汉沽区没有发现由于汞污染所造成的植物受害症状。植物中的汞含量与土壤中的汞含量成正相关。土壤汞含量与水稻茎叶汞含量的相关系数为0.836(N=7),与糙米汞含量的相关系数为0.898(N=7)。植物不同部位的汞含量根>叶>茎>种子。不同作物种子比较,糙米>高粱>小麦。在大气中汞含量高的地段,植物地上部分汞含量高于根。土壤、植物中的汞不断地向大气扩散,而大气中的汞随着降雨、降尘等又不断地沉降到土壤和植物的气生表面,并可被植物吸收。汞向其邻近地区扩散的能力较小。     

30种园林植物对短期大气污染的生理生态反应

 30种2～3年生园林植物分别盆栽于不同污染强度的工业生产区、交通繁忙区和相对清洁区,在第一生长季结束后对各试验区植物叶片气体交换特征参数进行测定,评价了大气污染对不同植物种类的可能影响效果。结果表明：工业污染区和交通繁忙区均有较高的SO2浓度,交通繁忙区NOx浓度明显高于其它试验区。根据综合污染指数,3个试验区污染强度为交通繁忙区>工业污染区>相对清洁区。生长在污染区的大多数植物的净光合速率（Pn）、蒸腾速率(E)和气孔导度（gs） 均出现不同程度的下降,下降幅度因植物种类不同而有较大差异。植物Pn、E与gs之间存在显著线性相关关系,表明多数植物能够感应污染胁迫和调节气孔开张度,是植物对胁迫环境的一种适应策略。但是污染胁迫下Pn、E与gs线性相关的显著程度被削弱,表现出污染胁迫下不同植物种类Pn和E的变化与gs变化的不协同性和复杂性。根据Pn下降程度可将植物分组为轻度敏感（11种）、中度敏感（11种）和高度敏感植物（8种）。      

Evaluation of Environmental Quality of Atmosphere by Determination of Element content in Plants and Soils in Tianjin

165 plants and 40 soil samples were collected at seven areas in Tianjin. The analysis of sulphur and heavy metals in these samples showed the polluted degree of the air. It is indicated that the plants at smeltery (polluted industry area) contain Zn, Cu, Cd, Pb highest and NJ, S higher. The content of heavy metals in these plants were 3 to 11 times higher than that of the background value. In business-traffic area and park, the amount of Zn, Cu, Ni, Cd in the plants were 1.5 to 3.5 times higher than the background value. In the other area, such as culture-education area, road and suburbs, the pollution is not significant, and in the clean area (Panshan), all elements in the plants are the lowest. As to the soils in polluted industry area (Smeltery), the amount of Ph, Cu, Cd, Zn and S was 725, 348, 9, 3 and 14 times higher than that of the background value respectively. Among them, most of Pb, Cu were deposited in surface layer. In soil of business-traffic area, Pb, Cu, Cd, Zn and S were 2 to 10 times higher than the background value, and in the soil of clean area, all elements are also the lowest. The stomata of plants which were blocked by the particles going down from the air resulted in increase in the stamotal diffusive resistance and the order of the resistance in the different places are as follows: polluted industry areas > parks > business-traffic areas > road > clean areas. These results are in agreement with the polluted state of the plants and soils in above mentioned areas.     

近20年来京津冀地区土壤风蚀扬尘颗粒物排放变化

京津冀地区是我国大气污染严重区域,土壤扬尘颗粒物排放变化研究对于改善京津冀地区空气质量具有重要意义。收集2000-2019年京津冀地区气候、土壤、植被覆盖数据,分析近20年来京津冀地区土壤扬尘颗粒物排放变化,揭示其变化的影响因素。结果显示2000-2019年京津冀地区土壤扬尘源总悬浮颗粒物（TSP）排放系数均值为1.79 t km^-2 a^-1,其中PM10占8.99%,PM2.5占0.25%。近20年土壤扬尘源TSP排放系数具有下降趋势,PM10和PM2.5排放系数变化过程与TSP一致。上述变化主要受气候因子变化影响,其次受植被覆盖度影响。分析发现近20年来京津冀地区土壤扬尘源TSP排放系数变化主要受年降水量影响。沧州市、天津市和石家庄市土壤扬尘源TSP、PM10和PM2.5排放系数均值较高,张家口市、保定市和沧州市土壤扬尘源TSP排放量占京津冀地区总量的19.18%、12.98%和11.63%。耕地土壤扬尘排放量最大占京津冀地区总量的59.83%,是抑制土壤扬尘源颗粒物排放的重点关注对象,其次为草地占15.66%。2019年邢台市土壤扬尘源PM10排放占观测值比例最高为12.66%,石家庄市和天津市占比也较高分别为11.09%和10.30%,沧州市和邯郸市占比分别为8.63%和8.02%。上述地区环境管理部门均应关注土壤扬尘源颗粒物排放对空气质量的影响。     

Bioaccumulation of thallium by the wild plants grown in soils of mining area

Gümüsköy Ag (As, Pb, and Tl) deposits are one of the largest silver deposits in the country and located about 25 km west of Kütahya, Turkey. This study investigated the accumulation and transport of thallium into 11 wild plants in soil of the mining area. Plant samples and their associated soils were collected from the field and Tl contents were measured with inductively coupled plasma mass spectroscopy (ICP-MS). The mean concentrations in the soil, roots, and shoots of the studied plants were, respectively, 170, 318, and 315 mg kg^?1 for Tl. The plants analyzed and collected from the studied area were separated into different groups based on enrichment coefficients of roots and shoots (ECR and ECS). The results showed that because of their higher ECR and ECS, the following could be good bioaccumulators: CY, IS, SL, and VR for Tl. Therefore, these plants can be useful for remediation or phytoremediation of soils polluted by Tl.     

Patterns of understory diversity in mixed coniferous forests of southern California impacted by air pollution

The forests of the San Bernardino Mountains have been subject to ozone and nitrogen (N) deposition for some 60 years. Much work has been done to assess the impacts of these pollutants on trees, but little is known about how the diverse understory flora has fared. Understory vegetation has declined in diversity in response to elevated N in the eastern U.S. and Europe. Six sites along an ozone and N deposition gradient that had been part of a long-term study on response of plants to air pollution beginning in 1973 were resampled in 2003. Historic ozone data and leaf injury scores confirmed the gradient. Present-day ozone levels were almost half of these, and recent atmospheric N pollution concentrations confirmed the continued air pollution gradient. Both total and extractable soil N were higher in sites on the western end of the gradient closer to the urban source of pollution, pH was lower, and soil carbon (C) and litter were higher. The gradient also had decreasing precipitation and increasing elevation from west to east. However, the dominant tree species were the same across the gradient. Tree basal area increased during the 30-year interval in five of the sites. The two westernmost sites had 30-45% cover divided equally between native and exotic understory herbaceous species, while the other sites had only 3-13% cover dominated by native species. The high production is likely related to higher precipitation at the western sites as well as elevated N. The species richness was in the range of 24 to 30 in four of the sites, but one site of intermediate N deposition had 42 species, while the easternmost, least polluted site had 57 species. These were primarily native species, as no site had more than one to three exotic species. In three of six sites, 20-40% of species were lost between 1973 and 2003, including the two westernmost sites. Two sites with intermediate pollution had little change in total species number over 30 years, and the easternmost site had more species in 2003. The easternmost site is also the driest and has the most sunlight filtering to the forest floor, possibly accounting for the higher species richness. The confounding effects of the precipitation gradient and possibly local disturbances do not show a simple correlation of air pollution with patterns of native and invasive species cover and richness. Nevertheless, the decline of native species and dominance by exotic species in the two westernmost polluted sites is cause for concern that air pollution is affecting the understory vegetation adversely.     

Regional distribution characteristics and ecological risk assessment of heavy metal pollution of different land use in an antimony mining area – Xikuangshan,China

Abstract

Mining activities have introduced various heavy metals and metalloids to surrounding soil environments, causing adverse impacts to the ecological environment system. The extremely high concentration of various heavy metals and metalloids make the Xikuangshan (Hunan, China) an excellent model to assess their ecological risk. In this study, the soil samples from 26 locations of different land use methods in four areas (smelting area, road nearby ore, mining area, and ore tailing area) in Xikuangshan with different levels of various heavy metals and metalloids (Sb, As, Pb, and Cd) were analyzed; in addition, the index of geo-accumulation and the potential ecological risk index were used to evaluate ecological risk. The results showed that the average contents of Sb, As, Pb, and Cd in all soil samples were 4368.222?mg·kg^?1, 40.722?mg·kg^?1, 248.013?mg·kg^?1, and 40.941?mg·kg^?1, respectively, implying serious contamination of compound pollution of heavy metals in soil. The concentration of heavy metals in soil among smelting area, road nearby ore, mining area, and ore tailing area showed significant distribution characteristics of region because different mining activities such as smelting, mining, transportation, and stacking caused different pollution intensity. Moreover, the contents of Sb in soil samples decreased successively in residue field, wasteland, forestland, sediment, grassland, and vegetable field, and the contents of Sb in vegetable-field and ecological restoration grassland were relatively low, which indicate that the method of grassland ecological restoration is an effective method to control antimony pollution in soil. The results of ecological risk assessment showed that the antimony mining area was seriously polluted by Sb, As, Pb, and Cd, and had strong ecological risk, and Sb and Cd were the most important pollution factors, which indicated that the pollution of Sb and Cd should be a major concern of relevant departments of environment and health.     

Assessment of Heavy Metal Contamination in the Surrounding Soils and Surface Sediments in Xiawangang River,Qingshuitang District

Xiawanggang River region is considered to be one of the most polluted areas in China due to its huge amount discharge of pollutants and accumulation for years. As it is one branch of Xiang River and the area downstream is Changsha city, the capital of Hunan Province, the ecological niche of Xiawangang River is very important. The pollution treatment in this area was emphasized in the Twelfth Five-Year Plan of Chinese government for Xiang River Water Environmental Pollution Control. In order to assess the heavy metal pollution and provide the base information in this region for The Twelfth Five-Year Plan, contents and fractions of four heavy metals (Cd, Cu, Pb and Zn) covering both sediments and soils were analyzed to study their contamination state. Three different indexes were applied to assess the pollution extent. The results showed this area was severely polluted by the four heavy metals, and the total concentrations exceeded the Chinese environmental quality standard for soil, grade III, especially for Cd. Moreover, Cd, rated as being in high risk, had a high mobility as its great contents of exchangeable and carbonates fractions in spite of its relative low content. Regression analysis revealed clay could well explain the regression equation for Cd, Cu and Zn while pH and sand could significantly interpret the regression equation for Pb. Moreover, there was a significant correlation between Non-residual fraction and I_geo for all the four metals. Correlation analysis showed four metals maybe had similar pollution sources.     

Evaluation of genotoxicity of Pseudevernia furfuracea (L.) Zopf by RAPD analysis

We investigated the suitability and applicability of Pseudevernia furfuracea (L.) Zopf for environmental genotoxicity assessment. P. furfuracea lichen specimens were collected from 10 different Pinus species, in every 5 km, starting from around an iron-steel factory located in the central area of Karabük Province up to Yenice Forest. The impact of the pollution sources such as iron-steel factory, roads and railroads, industry, heavy traffic, and waste treatment plants on the heavy metal accumulation in lichens is known. DNA changes in P. furfuracea samples exposed naturally to various polluted sites were analyzed by RAPD to know the influence of the environmental pollution on the hereditary material of the organisms. Twenty-five different primers were tested and 10 yielded clear and reproducible bands. The present study shows the suitability of the lichen samples for the detection of genotoxicity and also provides information about the level of potential genotoxic agents around a steel mill.