废弃汞矿山苔藓植物群落生态研究

对贵州省铜仁市云场坪镇废弃汞矿山的苔藓植物群落进行了研究,通过野外全面调查和实验室仔细鉴定,发现废弃汞矿山苔藓植物群落的种类组成有13科52属62种(苔类植物2科2属2种,藓类植物11科50属60种)。应用双向指示种分析法(TWlNSPAN)和除趋势对应分析(DCA)分析其分布格局表明,该区12个样点分为2个类型组,组1为废石、废渣样地,组2为废洞样地,说明废洞与废石、废渣生境差异性较大,废石、废渣生境较相似;北地扭口藓群落（Barbula fallax Com.）、阔叶小石藓群落（Weisia planifolia Com.）、尖叶扭口藓群落（Barbula constricta Com.）、拟丛净口藓群落（Gymnostomum anoectangioides Com.）、硬叶净口藓群落（Gymnostomum subrigidulum Com.）为该矿区废石、废渣上的优势群落,其生物量为55.20~448.20 g·m^-2,饱和吸水量为260.80~3 599.40 g·m^-2,说明在矿区这种干旱且保水能力弱的环境区域,苔藓植物群落以其特有的生态功能在矿区生态环境治理中具有十分重要的作用。     

新疆古尔斑通古特沙漠南缘土壤结皮中苔藓植物的研究

对新疆古尔班通古特沙漠南缘土壤结皮中苔藓进行了研究。结果表明,该地区参与土壤结皮的有4种苔藓植物,即真藓（Bryum argentum)、细叶真藓（Bryum capillare)、无齿紫萼藓（Grimmia anodon)和垫状紫萼藓（Grimmia puluinata),并分析了其耐旱特性和分布特征;研究发现该地区苔藓结皮呈层片分布规律,由表及里依次为苔藓植物层,无机沙砾层1、藻结皮层,无机沙砾层Ⅱ等4层。     

内蒙古准格尔黄土丘陵区不同植被类型地面生苔藓植物物种多样性研究

在野外样方调查的基础上研究了准格尔黄土丘陵沟壑区9种不同植被类型地面生苔藓植物物种多样性及其与环境因子之间的相关性:(1)共发现苔藓植物8科18属35种,以丛藓科(Pottiaceae)和真藓科(Bryaceae)为优势科,优势种有真藓(Bryum argenteu)、双色真藓(Bryum bicolor)、土生对齿藓(Didymodon vinealis)、褶叶青藓(Brachythecium salebrosum)、灰藓凹叶变种(Hypnum cupressiforme var.lacunosum)等10种;(2)Alpha多样性指数中,Patrick丰富度指数在4~21种,Shannon-Wiener指数和Simpson多样性指数分别在1.078 0~2.153 3和0.588 9~0.826 3,天然植被变化规律为杜松林(Juniperus rigida forest)茭蒿群落(Artemisia giraldii shrub)山桃林(Prunu davidiana forest)锦鸡儿群落(Caragana intermedia shrub)本氏针茅群落(Stipa bungeana steppe)百里香群落(Thymus serpyllum steppe),而人工杨树林(Populus simonii forest)、侧柏林(Platycladus orientalis forest)与锦鸡儿灌丛以及人工油松林(Pinus tabulaeformis forest)与杜松林上述3个指数相近;(3)影响物种多样性的主要环境因子有土壤水分、空气湿度和光照强度;(4)Bata多样性指数在0.240 0~0.857 1,本氏针茅群落与人工杨树林物种相似性最大,百里香群落与杜松林物种相似性最小,群落之间物种组成相似性和差异性能够揭示各样地生境差异性和相似性。杜松林下的苔藓植物物种多样性为最高,是该地区地面生苔藓植物物种多样性保护的主要地区。     

张家湾子金矿苔藓植物物种多样性及其对重金属污染的监测

调查了贵州省张家湾子金矿苔藓植物,并利用原子荧光光谱仪AF-640和AAnalyst800原子吸收光谱仪,对重污染区、相对污染区和清洁区苔藓植物优势种及土壤基质6种重金属元素(Cu、Zn、Cd、Pb、Hg、As)含量进行测定.在该金矿共采集苔藓样品75份,鉴定为9科16属23种.优势科为丛藓科和真藓科,生活型主要有4种:矮丛集型、高丛集型、交织型和平铺型,矮丛集型以80.3％占绝对优势.重金属含量测定结果表明,该矿区受Hg、As、Cd污染严重;硬叶净口藓对Cd的富集系数为5.58,属于强烈富集;匐灯藓对Cd富集系数为1.64,属于相对富集.苔藓与土壤重金属含量呈正相关,苔藓植物能监测该矿区重金属污染.     

贵州省新路卡林型金矿区苔藓植物多样性及重金属污染监测

研究发现新路卡林型金矿区苔藓植物有10科17属28种,其中,丛藓科有9种,占总数的32.14%,真藓科有8种,占总数的28.57%。真藓科和丛藓科为优势科。分析该卡林型金矿区4个生境的β多样性,发现废石区—废渣区与相对污染区—清洁区的β多样性指数差异最大,苔藓群落结构差异性最大,相似性成分最低。测定该矿区苔藓植物及相应基质的重金属元素Pb、Zn、Cu、Cd、Hg、As含量,发现这些重金属元素含量呈现了一定的规律性,即：废渣区>废石区>相对污染区>清洁区,这可能与金矿的开采和冶炼有密切联系。因此,通过对苔藓植物的深入研究,可用以监测卡林型金矿区重金属污染情况。     

贵州贞丰喀斯特石漠峰丛苔藓植物群落生态特征

调查和分析了贵州贞丰县喀斯特石漠地区的3座典型峰丛、3个山段上苔藓植物群落的种类组成及其生态特征。研究区域内,苔藓植物群落的种类组成有12科16属19种。苔藓植物群落共21个类型,其中纯群落占83.3%,两种及两种以上苔藓组成的群落占26.7%,占优势的群落是皱叶牛舌藓群落（Anomodetum）、卷叶湿地藓群落（Hyophiletum）和卷叶毛口藓群落（Trichostometum）。苔藓植物群落物种为适应旱生、干燥和强光直射的环境,生活型仅有交织型和矮丛集型两类。由于人类强烈的活动破坏了原有的生态系统,苔藓群落的分布在石漠峰丛中显示出了特异性,苔藓群落的丰富度为山顶＞山腰＞山脚。各山段的皱叶牛舌藓群落均有最大的生态优势度,具有治理石漠的潜在价值。     

西藏东部高寒草甸苔藓植物群落数量分类与排序

为探讨高寒草甸苔藓植物群落分布格局及其与环境因子之间的关系,按网格法在西藏东部的林芝市和昌都市设置了28个高寒草甸样地,采用双向指示种分析(TWINSPAN)、除趋势对应分析(DCA)和典范对应分析(CCA)的方法对群落进行数量分类和排序。结果显示,共记录有苔藓植物19科30属60种,均为藓类植物;其中,丛藓科和真藓科的物种数占总种数的55%。群落优势种为北地对齿藓(Didymodon fallax)、垂枝藓(Rhytidium rugosum)、山羽藓(Abietinella abietina)、厚角绢藓(Entodon concinnus)、尖叶对齿藓芒尖变种(Didymodon constrictus var.flexicuspis)和短叶对齿藓(Didymodon tectorus)。根据TWINSPAN分析结果可将西藏东部高寒草甸苔藓植物群落划分为9个群丛,分别为沙氏真藓(Bryum sauteri)群丛、细枝羽藓(Thuidium delicatulum)+狭网真藓(Bryum algovicum)+羽枝青藓(Brachythecium plumosum)群丛、尖叶对齿藓芒...     

喀斯特石漠化区苔藓植物物种多样性变化

为了揭示喀斯特石漠化地区苔藓植物的物种多样性,通过野外实地调查对贵州喀斯特地区不同程度石漠化区域苔藓植物进行研究。结果表明,苔藓的科、属、种数量随着石漠化程度加剧而下降,其中,强度石漠化的科数最少且显著低于其他三种石漠化类型,比潜在、轻度、中度石漠化地区苔藓科数分别降低70.00%、57.14%、33.33%;轻度石漠化地区的真藓科、青藓科、丛藓科、曲尾藓科等包含属数较多,占总属数34.62%;Shannon-Wiener指数和Simpson指数变化基本一致,随石漠化程度加剧而下降,其中苔藓植物在潜在石漠化地区Shannon-Wiener指数为1.9393,高于其他三种石漠化区域,比强度石漠化区高43.97%,Simpson指数以轻度石漠化过渡到中度石漠化地区物种丰富度下降最快,下降26.73%;潜在石漠化区较其他三个区域拥有更高的苔藓数量。说明苔藓植物的分布和石漠化程度密切相关,随着石漠化程度加重,苔藓植物的科、属、种总数均有不同程度下降。     

小秦岭自然保护区苔藓植物群落数量分类、排序及多样性垂直格局

苔藓物种多样性沿海拔梯度呈什么样的分布格局?基于53个20 m×20 m样地,采集并鉴定了样地内所有生境中的苔藓物种;采用多元回归树(multivariate regression trees,MRT)对苔藓植物进行分类;采用典范对应分析(canonical correspondence analysis,CCA)进行排序分析;用广义线性模型(Generalized Linear Model,GLM)研究苔藓物种多样性沿海拔的分布格局。结果如下:(1)采集的1378份苔藓植物标本经过鉴定,共有33科89属240种,其中藓类226种,苔类14种;(2)经交叉验证认为本区苔藓植物可分为4类,Ⅰ长肋青藓(Brachythecium populeum)+大叶匐灯藓(Plagiomnium succulentum)+圆叶匐灯藓(Plagiomnium vesicatum)群落,Ⅱ灰白青藓(Brachythecium albicans)+宽叶青藓(Brachythecium curtum)+短肋羽藓(Thuidium kanedae)+平肋提灯藓(Mnium laevinerve)群落,Ⅲ短肋羽藓(Thuidium kanedae)+光萼叶苔(Jungermannia leiantha)+薄罗藓(Leskea polycarpa)+叉肋藓(Trachyphyllum inflexum)群落,Ⅳ宽叶青藓(Brachythecium curtum)+垂蒴棉藓(Plagiothecium nemorale)+全缘匐灯藓(Plagiomnium integrum)群落;(3)海拔、坡度和坡向对苔藓物种分布的解释量为7.29%;(4)苔藓物种多样性随海拔的变化成明显的上升格局。通过研究了解了小秦岭国家级自然保护区苔藓物种组成、群丛划分以及每种苔藓植物的海拔分布范围;苔藓物种多样性随海拔的上升呈显著的上升格局,与乔木、灌木和草本的分布格局不同。希望此研究能为苔藓植物生态学研究和物种多样性保护提供参考。     

重庆主城区住宅小区苔藓组成与多样性

目前对于人造生活环境中的苔藓植物组成与多样性所知甚少。本文报道了城市住宅小区中的苔藓植物多样性, 以丰富重庆市苔藓植物区系资料, 为小区环境质量评估提供依据, 为认识苔藓植物对新环境的适应能力提供科学基础。通过对重庆主城九区23个住宅小区进行详细调查, 报道苔藓植物19科33属84种。种类组成以土生的丛藓科和真藓科为主。常见种类包括小凤尾藓(Fissidens bryoides)、大叶石灰藓(Hydrogonium majusculum)、细叶小羽藓(Haplocladium microphyllum)、鳞叶藓(Taxiphyllum taxirameum)和绿片苔(Aneura pinguis)共5种。各住宅小区苔藓物种数介于5-25种之间。物种相似性程度非常低, 群落间差异较为显著, 多样性较高。苔藓生活型以丛集型为主。典范对应分析排序结果显示, 住宅小区居住户数对其苔藓物种多样性影响最大, 其次是绿地面积。研究结果表明, 住宅小区是城市苔藓植物的重要分布区域之一。地理环境差异、城市化水平、小区内部小生境条件和人为干扰程度可能是造成各住宅小区苔藓组成差异的原因。     

岩溶洞穴苔藓群落特征及其对重金属污染的指示意义: 以贵州织金洞为例

岩溶洞穴的开发与利用导致的重金属污染严重威胁洞穴环境及地下水, 因此对洞穴环境的监测具有重要的现实意义。本文通过对典型的暗河型溶洞贵州织金洞内的苔藓群落特征及其重金属污染状况进行研究, 拟揭示苔藓群落对洞穴重金属污染的指示意义。共发现苔藓群落类型34个, 苔藓植物种类20科33属49种, 含苔类8科8属12种, 藓类12科25属37种。优势科为丛藓科、凤尾藓科和提灯藓科, 物种占比率分别为16%、14%、14%。Hg污染超标倍数最高达59.45倍, 在距洞口不同深度均远高于Cr和Zn, 说明洞内Hg污染较为严重。苔藓群落指标随着重金属污染含量的上升总体呈下降趋势。所测定的重金属中基质Hg含量与苔藓群落指标的拟合程度最好, 与其对应的苔藓群落指标均呈显著负相关关系(P < 0.05), 说明苔藓群落特征能够很好地反映洞内Hg污染的变化趋势。RDA排序结果分析表明: 洞穴苔藓群落为适应低光度环境会表现出向光性运动、喜钙生基质、耐重金属等生理特征。蛇苔(Conocephalum conicum)植物体内的Hg含量与其基质Hg含量具有显著相关性(P < 0.05), 说明蛇苔受基质Hg污染影响较大。在今后的治理过程中, 可以考虑将蛇苔作为洞内环境的生物监测材料之一。     

三江平原典型湿地植物中汞的分布与库存量

分析了三江平原典型植物中的总Hg浓度．结果表明,各种植物中总Hg浓度差别较大,苔藓>藻类>苔草>禾草>灌木;干湿环境是影响总Hg浓度的重要因素;湿地植物总Hg浓度高于水稻和玉米等农作物．较高的土壤总Hg浓度是近地面大气中Hg的重要来源,间接地影响到植物中Hg的浓度．植物各构件中总Hg浓度具有立枯>根>叶>茎的特点．在植物整个生长季总Hg浓度先增加后减少．估算了三江平原湿地植物Hg的库存量．小叶章湿地植物地上部分库存量为24．9μg·m^-2;毛果苔草湿地植物地上部分库存量为35．8μg·m^-2,高于加拿大实验湖泊湿地．     

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。     

Mercury determination in prehispanic Colombian biological samples: first experiences and investigation perspectives

Mercury is useful as a tracer of environmental pollution levels. We measured mercury levels in hair from two human mummies (XII and XIV centuries, respectively) and from a stag (Odocoileus virginianus). The total and inorganic mercury levels found in the samples were very low. This findings indicated a minimal exposure to mercury in food and its absence in the atmosphere. Mercury levels can be used to explore the relationship between humans and environment, especially after metallurgy appeared, and to assess environmental contamination in different periods.     

Building Capacity in Small-Scale Mining Communities: Health,Ecosystem Sustainability,and the Global Mercury Project

The Global Mercury Project (GMP) is an initiative of the United Nations in collaboration with numerous government and nongovernment organizations to promote knowledge and capacity building on the links between small-scale gold mining practices and health, ecosystem, and social factors, and to implement interventions that reduce mercury pollution and exposure caused by mining activities in developing countries. Knowledge regarding the use of mercury and the dynamics of complex environmental, health, socioeconomic, and cultural conditions in and surrounding small-scale mining sites is particularly needed for the purpose of developing appropriate community-based measures to reduce mercury-related problems. GMP strategies aim to build upon local knowledge and practices to train miners on the use of cleaner and affordable technologies of mining and mineral processing in order to minimize negative impacts. The initiative is especially proactive in facilitating transdisciplinary and participatory models of community interaction, involving local, regional, and international stakeholders in each of the strategy design, community assessment, and community intervention phases. The six participating countries are Brazil, Indonesia, Lao People’s Democratic Republic, Sudan, Tanzania, and Zimbabwe. This article outlines GMP’s objectives and scope of activities and also highlights achievements, challenges, and opportunities for future development.     

Response of epiphytic bryophytes to simulated N deposition in a subtropical montane cloud forest in southwestern China

A field manipulation experiment was conducted in a subtropical montane cloud forest in southwestern China to determine the possible responses of epiphytic bryophytes to increasing nitrogen (N) deposition from community to physiology level, and to find sensitive epiphytic bryophytes that may be used as indicators for assessing the degree of N pollution. N addition had significantly negative effects on species richness and cover of the epiphytic bryophyte community. Harmful effects of high N loads were recorded for chlorophyll, growth, and vitality of the species tested. The decline of some epiphytic bryophytes may result from detrimental effects on degradation to photosynthetic pigments. Bazzania himalayana (Mitt.) Schiffn., Bazzania ovistipula (Steph.) Mizut., and Homaliodendron flabellatum (Sm.) Fleisch. are candidates in atmospheric nitrogen monitoring. Epiphytic bryophytes in the montane cloud forest are very sensitive to increasing N deposition and often difficult to recover once they have been destroyed, providing early detection of enhanced N pollution for trees or even the whole forest ecosystem. The inference that increasing N pollution may lead to loss of biodiversity is a concern to the developing economy in western China, and should alert the government to the adverse impacts caused by increased industrial pollution during the process of China’s West Development.     

Mechanisms of mercury bioremediation

Mercury is one of the most toxic heavy metals, and has significant industrial and agricultural uses. These uses have led to severe localized mercury pollution. Mercury volatilization after its reduction to the metallic form by mercury-resistant bacteria has been reported as a mechanism for mercury bioremediation [Brunke, Deckwer, Frischmuth, Horn, Lunsdorf, Rhode, Rohricht, Timmis and Weppen (1993) FEMS Microbiol. Rev. 11, 145-152; von Canstein, Timmis, Deckwer and Wagner-Dobler (1999) Appl. Environ. Microbiol. 65, 5279-5284]. The reduction/volatilization system requires to be studied further, in order to eliminate the escape of the metallic mercury into the environment. Recently we have demonstrated three different mechanisms for mercury detoxification in one organism, Klebsiella pneumoniae M426, which may increase the capture efficiency of mercury.     

Relationship of Atmospheric Pollution Characterized by Gas (NO2) and Particles (PM10) to Microbial Communities Living in Bryophytes at Three Differently Polluted Sites (Rural, Urban, and Industrial)

Atmospheric pollution has become a major problem for modern societies owing to its fatal effects on both human health and ecosystems. We studied the relationships of nitrogen dioxide atmospheric pollution and metal trace elements contained in atmospheric particles which were accumulated in bryophytes to microbial communities of bryophytes at three differently polluted sites in France (rural, urban, and industrial) over an 8-month period. The analysis of bryophytes showed an accumulation of Cr and Fe at the rural site; Cr, Fe, Zn, Cu, Al, and Pb at the urban site; and Fe, Cr, Pb, Al, Sr, Cu, and Zn at the industrial site. During this study, the structure of the microbial communities which is characterized by biomasses of microbial groups evolved differently according to the site. Microalgae, bacteria, rotifers, and testate amoebae biomasses were significantly higher in the rural site. Cyanobacteria biomass was significantly higher at the industrial site. Fungal and ciliate biomasses were significantly higher at the urban and industrial sites for the winter period and higher at the rural site for the spring period. The redundancy analysis showed that the physico-chemical variables ([NO₂], relative humidity, temperature, and site) and the trace elements which were accumulated in bryophytes ([Cu], [Sr], [Pb]) explained 69.3% of the variance in the microbial community data. Moreover, our results suggest that microbial communities are potential biomonitors of atmospheric pollution. Further research is needed to understand the causal relationship underlined by the observed patterns.     

环境汞污染对藻类的毒性效应及其影响因素

综述了汞污染对藻类的毒性效应及影响因素。水环境中汞主要以元素汞、无机汞和有机汞3种形式存在。藻类吸附汞主要分为胞外的快速吸附和胞内的缓慢富集,在安全浓度内,金属汞对藻生长有一定的促进作用,随着浓度增大,抑制藻生长或致死。汞进入藻体细胞后,藻类为了存活会产生一系列保护机制。藻类对汞的排斥和排出作用可能就是对汞耐性的一种重要机制。藻类也可以通过多种方式减少汞进入藻类细胞,以及通过与其他物质结合汞使其排出胞外。温度、pH、生物学因素等影响重金属对藻类的毒性作用。并就藻类对汞耐性和适应机理、利用藻类修复和监测重金属污染、藻类响应汞胁迫的信号转导途径及其保护机制等未来研究领域进行了展望。     

Differential mercury volatilization by tobacco organs expressing a modified bacterial merA gene

INTRODUCTIONEnvironmental pollution is an increasing prob-lem both fOr developing and developed countries.Mercury, both in organic and ionic fOrm, is one of themost hazardous pollutants among the heavy met-als[l]and its accumuIation in human body results ininactivation of metabolic enzymes and structuralproteins[2, 3] giving rise to serious health problems(Minamatasyndrome).Usually mercury pollution is caused by indus-trial and agricultural activities, releasing mercuryinto air, water an…