地衣对放射性物质吸收和积累的初步研究

地衣植物对放射性物质具有富集作用,在国内有关这方面的研究工作尚未见有报道。本文作者对采自不同地区的22种地衣进行了低本底α,β射线总放射性的测定和NaI(TL)γ能谱的分析,结果表明:地衣中长寿命放射性核素有明显的积累现象,并呈现出一定的空间分布趋势。因而,了解地衣体中放射性含量水平、核素性质及分布状况,进而为研究环境放射学、地衣污染生态学等学科提供科学依据和基础资料。     

南极地区苔藓地衣植物的地球化学元素营养富集特征

研究南极苔藓地衣中地球化学元素的营养富集特征,发现K,Ca为苔藓地衣中最活跃元素,主要以主动吸收的方式累积于苔藓地衣植物中,P极易富集在地衣的藻层,参与藻类的有机合成过程,苔藓容易富集环境中的S,Al,Si以被动吸收的方式累积于地衣中,同时Fe,Mg以被动吸收的方式累积于苔藓体内,根据元素的含量和营养作用,研究认为K,Ca苔地衣的大量无机营养元素,S,P为苔藓地衣的中等营养元素,Al,Si为苔藓地衣的环境累积元素。     

地衣—大气污染的指示灯

大气污染作为环境污染的主要因素已越来越引起人们的重视 ,而对它的监测除了采用物理、化学监测手段外 ,生物监测更以其简便、真实、灵敏等其它任何监测手段所无法比拟的优越性而倍受青睐。地衣就是其中的代表。1　地衣简介地衣是一种与藻类共生的专化性真菌 ,常以真菌来命名。真菌类常为盘菌纲和核菌纲 ,少数为伞菌目和非褶菌目。而构成地衣的藻类有绿藻和蓝藻共 2 0多属。地衣的藻菌关系有 :1)共生关系　即地衣中的菌丝缠绕藻细胞 ,并从外面包围藻类。藻类进行光合作用 ,制造有机物 ,供藻类与菌类共同需要 ;菌类则吸收水分、无机盐和 O2 …     

地衣特殊性、多样性及其重要性

本文从地衣二元性和地衣的真菌本质、地衣物种、生活环境和生命力、生长速度、代谢产物等方面阐述地衣的特殊性与多样性及其在共生进化研究、监测大气污染、测年、药用诸方面表现出的科学意义与实用价值。并在地衣的开发利用中,提出地衣多样性的保护与永续利用的建议。     

地方特殊性,多样性及其重要性

本文从地衣二元性和地衣的真菌本质、地衣物种、生活环境的生命力、生长速度、代谢产物等方面阐述地方的特殊性与多样性及其在共生进化研究、监测大气污染、测年、药用诸方面表现出的科学意义与实用价值。并在地衣的开发利用中,提出地衣多样性的保护与永续利用的建议。     

1990年生态学学科获国家自然科学基金资助研究项目(续)

一一一一气厂育一了飞厂一一一一压飞币一一一一不__~_._~ 人工放射性核素在大亚湾海洋食物链的积累{林植青冲国科学院南海海洋研究所 多氯酚的微生物降解{张春桂i中国科学院沈阳应用生态研究所 因定化活性污泥处理废水生物学基础研究}俞毓馨}清华大学 地衣中放射性核素吸收的动态效应}吴金陵一中国学院科西北植物研究所 有机磷农药迟发性神经毒性及其机理的研究{谢遵逸一中国科学院动物研究所 毒物在水生微宇宙中的分布、生物积累和生物放大研究}金洪钧1南京大学 海洋生物附着与金属腐蚀关系的研究}王秋一青岛海洋大学 厌氧发酵光合菌与甲…     

揭开地衣中的共生奥秘（一）

地衣是一个相当大的生物类群,五界生物之一的真菌中,有20％的种类是地衣。在8％的地球陆地表面,地衣成为优势植被。地衣的分布范围很广泛,可以在地球上最高、最寒冷、最潮湿、最炎热和最干燥的陆生环境中生存,有些种类甚至能生活在水下。然而在大城市和工矿业生产区,几乎很难见到地衣,形成了“地衣荒漠”。这是大气污染的严重后果,人们正在利用这一现象监测大气污染的程度。     

低放核素污染土-水介质的植物修复研究进展

植物修复技术是利用植物根系吸收水分和养分的过程来吸收和转化土壤和水体中的污染物,以期达到清除,修复和治理的目的,是用于对土壤-水体中重金属和放射性核素污染清除的生态技术.本文就放射性核素的来源、污染现状、植物对放射性核素的积累筛选以及对污染土壤的修复研究进行综述,以明确植物修复技术在改善环境中的作用,为进一步筛选超积累植物并探讨植物对放射性核素污染的修复机理提供参考.     

地衣生态功能研究进展

地衣是陆地上一个数量庞大的生物类群,生存能力极强,是自然生态系统的重要组成部分,具有重要的生态功能。本文在对地衣生态习性特征进行归纳总结的基础上,阐述了地衣在土壤理化性质改良、固碳及固氮作用与环境监测等方面的生态功能及研究进展,旨在为充分发挥地衣在生态环境监测与保护方面的作用提供科学依据。最后分析了当前研究中存在的问题,并展望了今后的研究重点。     

石质文物地衣生物腐蚀及防治的研究进展

本文主要从生物因素方面考虑,分析了导致石质文物病害的主要原因和机理,并综述了国内外石质文物保护的现状、防治和修复方法。地衣是引起石质文物腐蚀的关键生物类群,与国外相比,目前国内专门针对地衣进行石质文物防治的研究鲜见报道。作者建议,石质文物的地衣生物腐蚀及防治研究应从以下方面入手：（1）石质文物地衣必须首先进行系统的种类调查;（2）对地衣腐蚀石质文物的机理进行深入研究;（3）探寻地衣病害安全有效的去除方法;（4）逐步探索地衣病害修复后的监测和预防方法。     

外阴硬化性苔癣组织P53、PCNA表达、DNA含量及与细胞增殖的关系

探讨外阴硬化性苔癣组织中的 P5 3、PCNA表达 ,DNA含量与细胞增殖的关系。免疫组化方法测定 2 0例外阴硬化性苔癣组织和 10例正常外阴皮肤中 P5 3、 PCNA蛋白表达 ;图像分析技术检测两组基底层细胞核形态及 DNA含量。结果显示 ,外阴硬化苔癣组 P5 3阳性表达率为 40 % ,与正常皮肤比较 P<0 .0 5 ,PCNA阳性表达率为 70 % ,与正常皮肤比较 P>0 .0 5 ,阳性表达主要分布于棘层、颗粒层 ;基底细胞核显著变小和 DNA含量降低 (P<0 .0 5 )。结果表明外阴硬化性苔癣组织中存在细胞增殖异常     

Monitoring changes in lichen resources for range management purposes in reindeer husbandry

Mat-forming lichens are important as food source for reindeer during the winter, and thus a vital resource to manage in reindeer husbandry. In this paper we suggest a method for monitoring of changes in lichen height with the purpose to early detect changes in lichen abundance in reindeer grazing areas. The method is intended for measuring geographically uniform lichen areas, evenly used for reindeer grazing. We analysed spatial variations in lichen height at the meter and 100 m scales, and calculated sample size requirements, and estimated effects of forest density and age, lichen moisture and lichen density on lichen height, and assessed the correspondence between lichen height and biomass. The variation in lichen height differed considerably between sites and, hence, the required sample size to detect a 5 mm change in lichen height with a power of 0.95 ranged from 200 to 2000, depending on the standard deviation of measured heights. Based on the autocorrelation in lichen height found between adjacent measurement points, a minimum distance of 4 m between measurement points is also recommended. Lichen height was significantly affected by lichen moisture, and the results suggest that this effect of moisture might vary with lichen density. Lichen height varied spatially within the study sites, and the spatial variations were partly caused by forest age and density. Thus, gradual changes in the forest characteristics are likely to alter the spatial variation in lichen height and it is therefore important to regularly re-evaluate the locations of measurement points within the monitored area. This study provides suggestions for a variable that could be used as an indicator of changes in the lichen resource, and aspects that should be considered when designing a monitoring program. The accuracy of detecting changes depends on the monitoring efforts, i.e. the number and distribution of measurement points and how often an area is monitored. In conclusion, our results indicate that measurements of lichen height have considerable potential for monitoring of changes in lichen resources within reindeer husbandry.     

THE LICHEN VEGETATION OF CHALK AND LIMESTONE STREAMS IN BRITAIN

The results of a nationwide survey of lichens associated with streams on chalk and limestone are reported. The lichen communities are present as a series of overlapping bands related to length of submergence. These have been named the submerged, fluvial mesic, fluvial xeric and fluvial terrestrial zones. The flora involves around 50 lichens, many of which are rarely recorded specialists restricted to this habitat. The richest sites for submerged species are headwaters, especially around springs. Active tufa deposition and disturbance of the stream bed by farm stock are detrimental to aquatic lichens. Diversity further downstream is related to the amount of exposed limestone available for colonization, with topographical complexity also important. An investigation of the influence of water quality suggests that suspended solids (silting) is a significant determinant of lichen distribution together with eutrophication. 1996 The British Lichen Society     

PESTICIDE USAGE AND EPIPHYTIC LICHEN DIVERSITY IN ROMANIAN ORCHARDS

The epiphytic lichen floras of different orchards (intensive, semi-intensive apple cultivation and traditional old private garden) in North-West Romania were compared with and without pesticide treatment. Species richness was negatively influenced by the frequency of pesticide treatment.     

FREQUENCY,DIVERSITY AND ECOLOGICAL STRATEGIES OF EPIPHYTIC LICHENS IN THE SWISS CENTRAL PLATEAU AND THE PRE-ALPS

To identify representative quantitative criteria for the creation of a future Red List of epiphytic lichens, 849 trees in 132 long-term ecological observation plots in the Swiss Central Plateau and the Pre-Alps were surveyed by standard sampling. Based on the trees, frequency data of the lichen taxa observed are described by the log series model, indicating the controlling effect of few ecological factors. Based on the plots, four classes of scarcity, each comprising 25% of the species, were established. As a contribution to the development of a national, representative survey of lichens, α-diversity (species richness, species density) andβ-diversity (dissimilarity) were calculated in terms of region, vegetation formation, vegetation belt and for their combinations. Differences in lichen diversity between the Central Plateau and the Pre-Alps were caused by the bigger elevational range in the Pre-Alps, which resulted in a higher species richness. α-Diversity of forest and non-forest were similar, whereas each vegetation formation showed one third of its species restricted to it. The contributions to the total lichen diversity of crustose, foliose and fruticose as well as of generative and vegetative species was calculated. Specific features along the altitudinal gradient of vegetation belts emerged: the percentage of crustose and generative lichens declined with every altitudinal step, increased in fruticose and vegetative lichens, and was the same in foliose species.     

天山森林生态系统树生地衣植物群落数量分类及其物种多样性的研究

地衣是由低等植物中的藻类与菌类中的真菌和兰细菌共生而成的一群特殊的植物。由于耐寒耐旱对生活中的养分要求不高,在养纷贫瘠、环境恶劣的高山寒漠、平原、戈壁和沙漠中地衣都能生长,因而广泛地分布和生长在不同的生态环境中。有关新疆地衣方面的研究报道集中在物种分类水平上,对于地衣群落结构方面的研究比较少。因此,我们应用多元分析中的主分量分析及聚类分析方法对分布在天山森林生态系统中树生地衣植物群落进行数量分类并对群落结构物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明, 在西部天山不同森林生态系统中树生地衣群落的分布与海拔高度和树种有密切的关系, 不同海拔的不同类型的森林生态系统中分布着不同种类的树生地衣植物。 根据多元分析结果和生境的综合特征,该地区的树生地衣可划分为4种类型: 1) 茎口果粉衣+金黄茶衣群丛Chaenotheca stemonea+Candellaria aurella Association; 2)叉小孢衣+裸扁枝衣+粉唇蜈蚣衣群丛Bryoria furcellata+Evernia esorediosa+Physcia tribacoides Association; 3)亚广开梅衣+槽梅衣+疑小梅衣群丛Parmelia fertilis+Parmelia sulcata+Parmeliopsis ambigua Association; 4)睫毛黑蜈蚣衣+黑蜈蚣衣群丛Phaeophyscia ciliata+Phaeophyscia nigricans Association。其群落多样性指数以亚广开梅衣+槽梅衣+疑小梅衣群丛为最高 (1.920), 叉小孢衣+裸扁枝衣+粉唇蜈蚣衣群丛为最低 (1.562)。     

CONTINUOUS MONITORING OF CO2EXCHANGE OF LICHENS IN THE FIELD: SHORT-TERM ENCLOSURE WITH AN AUTOMATICALLY OPERATING CUVETTE

Field measurements of CO₂exchange by lichens are difficult because these poikilohydric organisms rely on direct hydration by rain, dew or fog. Continuous enclosure of thalli in conditioned, measurement cuvettes is, therefore, not experimentally reasonable. Porometric instruments with brief enclosure times, have proved useful for studies of lichen gas exchange but allow only spot measurements and recording is not easily possible for extended time periods. We describe a newly developed, automatically operating cuvette that allows long-term monitoring of lichen photosynthetic and respiratory CO₂exchange in the field. Samples, e.g. flat stone slabs covered with epilithic lichens, are positioned on the base of the cuvette where, when the cuvette is open, they are exposed to the same environmental conditions as naturally growing thalli. At regular intervals (typically 30 min), an upper lid automatically encloses the lichen forc. 3 min in a stirred cuvette; CO₂exchange is measured using IRGA techniques and microclimate data are recorded. The successful operation of the cuvette is illustrated by means of diel time courses of CO₂exchange for selected, very different weather conditions.     

Lichen flora around the Korean Antarctic Scientific Station, King George Island, Antarctic

As part of the long-term monitoring projects on Antarctic terrestrial vegetation in relation to global climate change, a lichen floristical survey was conducted around the Korean Antarctic Station (King Sejong Station), which is located on Barton Peninsula, King George Island, in January and February of 2006. Two hundred and twenty-five lichen specimens were collected and sixty-two lichen species in 38 genera were identified by morphological characteristics, chemical constituents, TLC analysis and ITS nucleotide sequence analysis.     

Long-term biomonitoring of lichen and bryophyte biodiversity at Burnham Beeches SAC and global environmental change

Long-term monitoring began 20 years ago at Burnham Beeches Site of Special Interest (SSSI), National Nature Reserve (NNR) and European Special Area of Conservation (SAC) lying 40 km west of London as a consequence of the authorization of an application to extract gravel from an adjacent site lying north of Slough Trading Estate. Dust monitoring (sticky pads) and photographic monitoring, recording and image analysis was instigated in 1992 on Parmelion communities to assess changes in lichen growth, health and community composition. Long-term monitoring identifies that the lichen flora on free-standing trees has undergone rapid expansion from a near dominance by the SO₂-tolerant ‘acidophyte’ species Lecanora conizaeoides and Hypogymnia physodes following reductions in SO₂ concentrations. Long-term influences of low levels of eutrophication, gaseous pollutants (particularly globally rising background ozone concentrations) on lichen and bryophyte communities and succession under changing climatic conditions are unknown. Soil–plant relationships, lichen–invertebrate interactions and a pollution legacy must also be considered.     

THE TOPICAL AND SYSTEMIC USE OF CORTISONE IN DERMATOLOGY

Part I of this report deals with the topical use of cortisone in a variety of skin diseases. Fifteen patients with chronic discoid lupus erythematosus, four patients with necrobiosis lipoidica diabeticorum, four with psoriasis, one with lichen planus and one with granuloma annulare were treated with cortisone ointment. All the patients with chronic discoid lupus erythematosus had some degree of improvement. In two patients with chronic lupus erythematosus, complete clearing of the eruption occurred. In four patients with necrobiosis lipoidica diabeticorum remarkable involution resulted. Patients with psoriasis, lichen planus and granuloma annulare were not benefited.Part II deals with the systemic use of cortisone. Eight patients with severe serum sickness-like penicillin reaction responded dramatically to parenterally administered cortisone. In two cases of pemphigus vulgaris and one case of Sulzberger-Garbe disease, the disease was kept in remission with cortisone administered intramuscularly as well as orally. Partial improvement resulted in a case of localized myxedema associated with malignant exophthalmus. Two patients with exfoliative dermatitis due to therapy with heavy metals responded dramatically to cortisone. No beneficial effects were noted in patients with chronic urticaria and atopic dermatitis.The systemic use of ACTH and cortisone in dermatology at present should be confined to patients with known fatal or hopelessly incapacitating diseases and to patients with extreme hypersensitivity reactions which may be protracted or life-endangering, and which can be controlled or cured with a relatively small total dosage of the agents in a short time.