贫困的生存状态对农村环境的影响——云南某山村的案例研究

"贫困是最大的污染者",贫困与环境恶化之间存在着显著的相互作用关系.为了进一步了解和认识贫困的环境影响,文章在理论分析的基础上进行了实证研究.首先提出了对农村环境的新定义:对农户而言,农村环境就是他们的生存环境,包括生产环境和生活环境.在此基础上,提出了表征农村环境的两个基本要素土地和农居环境和相应的表征指标.指出在农村环境问题的形成过程中,农户贫困的生存状态起着重要的作用,并且用具体的案例研究说明,在贫困山区,农户的贫困对于农户的生产与生活进步都产生了很大的限制,因此对于农村环境问题的研究和探讨应该从改善农户的经济行为开始,并且以摆脱贫困,改善农户的生存状态为目标,才可能最终达到改善农村环境,实现农村可持续发展的根本目标.     

活性炭及不同土壤吸附-超临界CO2再生四氯乙烯的特性

为解决干洗店等清洗行业排放的含四氯乙烯(PCE)三废的环境污染问题,开发一种使用经济、适用、有效且无污染的处理技术,需要收集相关的基础参数.文章研究了活性炭及兰州市三种不同的土壤对水中PCE吸附特性及超临界CO2再生活性炭及土壤萃取回收PCE的特性,结果表明,活性炭与土壤吸附水中PCE达到平衡的时间均为7 d,吸附等温线均可用Freundlich等温式拟合,且有较好的相关性;活性炭与不同土壤对PCE吸附能力差异较大,吸附能力由大到小为活性炭>林土>灌淤土>黄绵土,且土壤的吸附能力与土壤有机质、含水率及pH值关系密切;超临界CO2再生活性炭与土壤回收PCE,分别在35 ℃、20 MPa和60 ℃、20 MPa这样不太苛刻的条件下通过调整S/F值可获得较高的回收率,为PCE的污染治理技术提供理论依据.     

菲对黑麦草根系几种低分子量分泌物的影响

有机污染的植物修复过程与植物根系分泌密切相关,近年来,对于持久性有机污染多环芳烃的植物修复研究得到了很大发展,但对于多环芳烃污染下植物根系分泌物的研究很少.该实验以多年生黑麦草(Lolium perenne L.)为供试材料,以营养液栽培方式研究了在多环芳烃菲处理下,黑麦草根系对几种低分子量有机物的分泌情况.研究结果显示,黑麦草根系分泌有机酸、总糖以及氨基酸的量都随菲质量浓度的上升而变化.黑麦草根系分泌的低分子有机酸主要为草酸,在菲处理下,低分子有机酸的组成无明显变化,但含量随菲质量浓度上升而提高(由对照时的2.33 mg·g-1 FW升高至8 mg·L-1时的4.75 mg·g-1 FW);总糖和氨基酸含量均随菲质量浓度上升出现先升高后下降的趋势,但是最高值出现的菲质量浓度不同,从含量上来看,有机酸是黑麦草根系低分子量分泌物的主要部分.结合其它研究结果分析,植物分泌的有机酸可能在加速多环芳烃清除中发挥了重要作用.     

非生物胁迫诱导青蒿素生物合成基因的表达

对离体培养青蒿试管苗中3个青蒿素合成相关基因的非生物胁迫诱导表达模式进行了初步研究.半定量RT-PCR测定结果表明,当暴露于冷、热和紫外光后,青篙植株的紫穗槐-4,11-二烯合酶基因(ADS)和细胞色素P450单加氧酶基因(CYP71AV1)转录上调;相反,在未经胁迫处理的情况下,ADS和CYP71AV1基因的表达水平较低,而在胁迫处理前后细胞色素P450还原酶基因(CPR)转录所产生的mRNA均保持恒定.同时,冷胁迫的诱导效果也得到实时荧光定量RT-PCR测定数据的支持.经低温锻炼的青蒿试管苗,其ADS和CYP71AV1基因的转录产物拷贝数比对照分别提高11倍和7倍,而CPR基因的mRNA拷贝数与对照基本持平.短暂预冷处理还可显著提高青蒿试管苗的青蒿素含量,达到7.5～8.8 mg/g干重,比对照提高66.7%～95.6%,为进一步探索利用环境胁迫促进青蒿素高产的新途径提供了可能性.图2表3参21     

硅酸盐、腐殖酸对Cr污染土壤中小白菜生理及吸铬量的影响

针对在铬污染区土壤中的叶菜类吸铬量是果菜类2~3倍,以及硅酸盐或腐植酸在重金属污染土壤上的最佳施用量研究较少的问题,为保障蔬菜的品质安全,文章通过土壤盆栽试验,研究硅酸盐、腐殖酸不同用量对Cr污染土壤中小白菜(Brassica Chinensis)生理指标和吸铬量的影响.结果表明,施低质量分数的硅酸盐(1.0 g·kg-1)效果最佳,既能提高受Cr污染小白菜的生物量、叶绿素相对含量,又能减轻Cr毒害对抗氧化酶系统中SOD酶活性的抑制,缓解小白菜受到的过氧化胁迫,有效降低小白菜吸铬量;高质量分数硅酸盐(2.0 g·kg-1)对生长产生抑制.腐殖酸在设计的3个质量分数水平上均不能有效降低小白菜吸铬量,对生长的促进作用也不明显.     

大气压光电离源-液相色谱/飞行时间质谱的确认法用于河水、废弃流出物和污水中的雌性激素化合物的检测

近几年来,雌性激素对水环境的影响越来越大,因为这些化合物在浓度低至0.1 ng·l-1 时,都会导致雄性鱼的雌雄间性的变化.所以,需要一种具有灵敏度和选择性高的分析方法用于复杂样品中的雌性激素化合物的检测.     

唐鱼卵黄脂磷蛋白的纯化鉴定与免疫原性分析

采用Native-PAGE和SDS-PAGE方法从性成熟雌性唐鱼(Tanichthys albonubes)卵巢组织提纯了卵黄脂磷蛋白(Lv).已确定被纯化的唐鱼Lv在Native-PAGE(4%～7.5%)电泳中分子量(Mr)为314 ×103.用纯化的唐鱼Lv免疫大白鼠获得鼠源多克隆抗血清.以Native-PAGE和SDS-PAGE制备的唐鱼Lv及裂解后的组分作为抗原所制备的抗血清,与经17β-雌二醇(E2)诱导的雄性唐鱼、去除卵巢的雌性唐鱼以及唐鱼卵巢的匀浆液能发生免疫反应,并且印迹位置与雌性特异蛋白卵黄蛋白原(Vtg)的位置相当.但是两种血清和未经E2诱导的雄鱼整体匀浆液并无反应,显示Lv及其大分子亚基的抗血清与Vtg和Lv两种蛋白是特异的.结果表明,唐鱼Lv裂解组分的抗血清可用于检测唐鱼的Vtg.图3参19     

杞柳对水中2,4-二氯苯酚的降解

通过在人工配制的含有2,4-二氯苯酚(2,4-DCP, 2,4-Dichlorophenol)的营养液中培养杞柳(Salix integra),研究了杞柳在不同处理条件下对水溶液中2,4-DCP的去除效率,并探讨了其对2,4-DCP降解的动力学过程.结果表明,在抑菌和不抑菌处理条件下,杞柳对水溶液中的2,4-DCP有促进降解的作用,在96h内杞柳对20 mg·L-1的2,4-DCP去除效率分别为:76.9%、81.1%,并且对2,4-DCP的去除都符合一级动力学方程;而没有杞柳生长的水体中2,4-DCP的降解率为0%.2,4-DCP的植物吸收降解、微生物降解对2,4-DCP去除的贡献率约为:92.57%、7.43%.在模拟光照下,杞柳在48 h内能去除水中约52.37%的2,4-DCP.同时,根系组织中多酚氧化酶和过氧化物酶活性受到了2,4-DCP明显的抑制.试验所采用的质量浓度对杞柳没有产生毒害作用,表明杞柳是修复水中2,4-DCP较好的材料.     

淫羊藿果实成熟与生境的关系

以四川省南充市金城山3个不同海拔高度(562 m, 640 m和726 m)的淫羊藿为研究对象,对其果实成熟的时间及数量进行了研究;同时也对其果实成熟量与大气湿度、温度、光照强度之间的关系进行了研究.相关的数据分析表明,淫羊藿果实成熟过程可分为初始期、高峰期和末期3个阶段.果实成熟主要受湿度,光照和温度的影响.气温的突变可能是促进淫羊藿果实成熟的机制之一;果实数与相对光照、温度之间都存在极显著的相关性.随着海拔高度的变化,淫羊藿果实成熟时间也有相应变化.由于淫羊藿果实成熟后易自裂,所以研究不同生境淫羊霍果实成熟时间的差异对于淫羊霍种子的采收也相当重要.     

外源Cd对小白菜吸收与分配Cd、Zn的影响

采用盆栽试验研究外加Cd处理下红沙泥田和乌栅土中小白菜(Brassica chinensis L.)[四月慢(SYM)和高梗白(GGB)]对Cd、Zn的吸收与分配规律.结果表明:(1)小白菜对Cd、Zn的吸收积累受土壤类型、蔬菜品种和外源Cd剂量的影响,四月慢吸收Cd能力比高梗白强,外加Cd处理、土壤、品种间的正交互作用使小白菜植株Cd/Zn比值提高;(2)小白菜食用部位Cd/Zn比值并不服从于植株对Cd、Zn的总吸收量之比,而是取决于其在根和地上食用部位中的分配,Cd的地上部分配系数为56.3%～71.1%,而Zn则为77.6%～80.6%.在一定Cd处理水平下,地上部Cd分配系数下降,而Zn分配系数无明显变化,从而减缓了Cd/Zn比值升高的趋势,使小白菜地上部受Cd毒害的风险性降低;(3)2种小白菜对Cd和Zn的吸收动态随生长时间不同而异,Cd积累量随时间延长呈不断增加趋势,而对Zn的吸收积累能力自苗期后缓慢降低.这种差异使小白菜生长后期Cd/Zn比值升高,从而提高了小白菜Cd暴露的潜在风险.此现象在红壤加Cd处理下表现尤其明显.     

Book Reviews

INTERACTIONS OF PLANT RESISTANCE AND PARASITOIDS AND PREDATORS OF INSECTS by D. J. Boethel and R. D. Eikenbary, Editors. 224 pp. Ellis Horwood Limited 1986. ISBN 0-85312-836-7, £32.50.

ORGANIC TRACE ANALYSIS, by Klaus Beyermann, Translation editor: R. A. Chalmers. Ellis Horwood, Chichester. £35-00. ISBN 0853126380.

CADMIUM IN THE ENVIRONMENT. Part II: Health Effects. Edited by Jerome O. Nriagu. 908p. Wiley-Interscience, New York and Chichester. £85.00. I.S.B.N. 0-471-0554.     

Book Reviews

D. I. Wilson and A. N. Clarke (1994) Hazardous Waste Site Soil Remediation. 567 Pp. Marcel Dekker Inc., New York (Isbn 0-8247-8980-6), Price £ 108.85.

Symposium Mediterranean Seas 2000, Norberto F.-R. Della Croce (Editor), 489 Pp. Istituto Scienze Ambientali Marine 1993.

Organic Substances in Soil and Water: Natural Constituents and Their Influences On Contaminant Behaviour. Edited By A. J. Beck, K. C. Jones, M. H. B. Hayes and U. Mingelgrin. Published By the Royal Society of Chemistry (Special Publication No. 135), 1993, Isbn 0-85186-635-2, 200pp. Price £55.00

Chemical Fate and Transport in the Environment, H. F. Hemond and E. J. Fechner, Publ. Academic Press Inc., London, 1994. Isbn 0-12-340270-0, 338 Pp., $49.95

Biodegradation and Bioremediation, Alexander, A. (1994) 302 Pp. Academic Press Inc., San Diego, Isbn 0-12-049860-X, £38.00.     

Book Reviews

SOVIET SCIENCE REVIEWS-SECTION B., CHEMISTRY REVIEWS. Edited by M. E. Vol'pin. Volume 5. Organofluorine Chemistry pp 397. Volume 6. Organophosphorous Chemistry pp 442. OPA Ltd., for Harwood Academic Publishers, 1984. $170 each. Hardback. ISBN 3-7186-0139-7 and ISBN 3-7186-0139-7.

CURRENT TOPICS IN CHINESE SCIENCE-SECTION B., CHEMISTRY. Volume 2, pp 572 and Volume 3, pp 563. Gordon and Breach Science Publishers, 1984. $64 and $68 both soft covers. ISBN 0-677-06230-3 and ISBN 0-677-40385-2.

THE EXPORT OF HAZARD. Transnational Corporations and Environmental Control Issues. edited by Jane H. Ives. 229 pp. Routledge and Kegan Paul: Boston, London and Henley. £14.95. ISBN 07102 0072 2

ENVIRONMENTAL CHEMISTRY by Peter O'Neill. 232 pp. Allen and Unwin 1985. ISBN 0-04-551085-7, £20. ISBN 0-04-551086-5 Pbk, £8.95.     

濒危植物矮牡丹种群生物量的研究

对矮牡丹种群生物量的研究表明,矮牡丹地上无性小株的叶、茎干和根系的生物量可分别用m1（DW）＝－0．232＋000771A,ms（DW）＝0．370＋0．18000（D2H1）,mr（DW）＝1．54＋0．000338（AH1）来表示象矮牡丹这种似棕榈型生长型的小灌木,植冠面积容易测得,用植冠面积进行叶重的模拟最为准确随年龄的增长,矮牡丹种群各部分生物量都呈指数模式增长     

Book Reviews

Book reviewed in this article:
The Expendable Future: U.S. Politics and the Protection of Biological Diversity. Tobin, R.
Australian Ecosystems: 200 Years of Utilization, Degradation and Reconstruction. Saunders, D. A., Hopkins, J. M., How, R.A., eds.
Ecosystems of Florida. Myers, R. and Ewel, J., editors.
Nature Reserves: Island Theory and Conservation Practice. Sha- fer, Craig L.     

Book Reviews

Oxygen and Life Second BOC Priestley Conference by various editors. The Royal Society of Chemistry: Letchworth, 1981. £11.00 ISBN O 85186 825 8

The Estuarine Ecosystem Tertiary Level Biology Series by D.S. McLusky. 150pp. Blackie: Glasgow, 1981. £6.25 ISBN 0 216 91116 8 Pbk.

Fine Dissection of Ascoglossans by T. Gascoigne. 1980. Pub.: The Author, in conjunction with the Conchological Society. 32 pp. Price £1 post free from T. Gascoigne, 16a York Grove, London SE15, England.     

Book Reviews

Book reviewed in this article:
For the Common Good. Daly, H. E., and Cobb, J. B., Jr.
The Disappearing Russian Forest: A Dilemma in Soviet Resource Management. Barr, B. M., and Braden, K. E.
Natural Resources for the 21st Century. Sampson, R. N., and Hair, D.
Managing Global Genetic Resources: The US National Plant Germplasm System. Committee on Managing Global Genetic Resources: Agricultural Imperatives. Board on Agriculture, National Research Council.     

湖南木兰科新分类群

本文描述了湖南木兰科4个新分类群:重瓣紫玉兰、大叶云山白兰、铜色含笑和凹叶拟单性木兰。     

Inorganic mercury pharmacokinetics in man: a two-compartment model

Excreta data obtained from five human subjects and previously analyzed as part of a multicompartment model (Hall, L.L., P.V. Allen, H.L. Fisher, and B. Most. 1995. The kinetics of intravenously administered inorganic mercury in humans. In Kinetic models of trace element and mineral metabolism, ed. K.N.S. Subramanian and M.E. Wastney, 1-21. Boca Raton: CRC Press) were reanalyzed by means of a two-compartment model. The mobile compartment represents mercury of any form that is available for transport throughout the body. The immobile compartment represents mercury in forms that are not available for transport. The model simulates time profiles for body inorganic mercury and for fecal and urinary excretion. According to the model, intravenously administered mercury enters the body in the mobile form. Following administration, two distinct kinetic profiles were observed. In four of five subjects, mobile mercury in the body declined rapidly and the immobile form became dominant within 6 days. In these subjects, fecal excretion profiles were characterized by an initial phase dominated by excretion of mobile mercury lasting up to 6 days. This was followed by a slower phase during which mobile and immobile mercury were excreted in varying amounts. A similar pattern was seen in urinary profiles, but the initial phase is shorter and less pronounced. In each of these subjects, immobile mercury accounted for 84–94% of the total cumulative urinary excretion. The fifth subject showed a unique kinetic profile. Conversion of mobile to immobile mercury was slow and the two forms did not reach equivalence until approximately 70 days after dosing. Despite this fact, approximately 99% of fecally excreted mercury and 100% of urinary mercury originated in the immobile compartment. Possible explanations for the different profiles are discussed within the context of the model.     

Book Reviews

Book reviewed in this article:
Americans and Their Forests: A Historical Geography. Williams, M.
The Forest and the Trees: A Guide to Excellent Forestry. Robinson, G.
Population Harvesting: Demographic Models of Fish, Forest, and Animal Resources . Getz, W. M. and Haight, R. G. 1989.
Floristic Inventory of Tropical Countries: The Status of Plant Systematic, Collections, and Vegetation, Plus Recommendations for the Future. Campbell, D. G., and Hammond, H. D., editors. 1989.
Biotic Diversity in Southern Africa—Concepts and Conservation. Huntley, B.J., editor. 1989.
Amphibians and Roads. Langton, T. E. S., editor.1989.