龙葵、大叶井口边草和短萼灰叶对Pb、Cd和As污染农田的修复研究

以云南省个旧市重金属污染农田为研究对象,通过野外田间试验研究7种配置种植方式下龙葵(Solanum nigrum)、大叶井口边草(Pteris cretica var.nervosa)和短萼灰叶(Tephrosia candida)对Pb、Cd和As的吸收特征,探讨3种植物不同配置方式对Pb、Cd和As复合污染农田的修复潜力.结果表明:供试农田土壤Cd和As含量均超出GB 15618-1995《土壤环境质量标准》中的三级标准.所有不同植物配置种植方式中,龙葵地上部对Cd的吸收量最大,为(6.99±0.25) mg·kg-1,大叶井口边草地上部对As的吸收量最大,为(326.98±93.99) mg·kg-1,短萼灰叶地上部对Pb的吸收量最大,为(32.96±5.65) mg· kg-1,均低于超富集植物的临界阈值(Cd 100 mg· kg-1,As1 000 mg·kg-1,Pb 1 000mg· kg-1).比较7种种植方式对污染土壤中重金属的提取效率发现,单作龙葵条件下,龙葵地上部对Pb、Cd和As的吸收量最大,年吸收量分别为1 004.97、152.04和1 534.47g· hm-2,若将Cd和As污染农田土壤修复达到GB 15618-1995中的三级标准,提取效率分别为2.811 6％和1.413％.这说明单作龙葵对Pb、Cd和As复合污染农田具有一定修复潜力,但不适用于修复高浓度重金属污染农田.     

Accumulation of heavy metals in four grasses grown on lead and zinc mine tailings

A field experiment was conducted to compare the growth and metal accumulation of Vetiveria zizanioides, Paspalum notatum, Cynodon dactylon and Imperata cylindraca var. major on the tailings, amended with 10 cm domestic refuse complex NPK fertilizer(Treatment A), 10 cm domestic refuse(Treatment B) and complex NPK fertilizer(Treatment C) respectively, and without any amendment used as control (Treatment D). The results indicated that V. zizanioides was a typical heavy metal excluder, because the concentrations in shoots of the plants were the lowest among the four plants tested. The most of metal accumulated in V. zizanioides distributed in its root, and transportation of metal in this plant from root to shoot was restricted. Therefore, V. zizanioides was more suitable for phytostabilization of toxic mined lands than P. notatum and C. dactylon, which accumulated a relatively high level of metals in their shoots and roots. It was also found that I. cylindraca var. major accumulated lower amounts of Pb, Zn and Cu than C. dactylon and P. notatum, and could also be considered for phytostaliUsaton of tailings. Although the metal(Pb, Zn and Cu) concentrations in shoots and roots of V. zizanioides were the lowest, the total amounts of heavy metals accumulated in shoots of V. zizanioides were the highest among the four tested plants due to the highest dry weight yield of it. The results indicated that V. zizanioides was the best choice among the four species used for phytoremediation (for both phytostabilization and phytoextraction) of metal contaminated soils.     

A protocol for the evaluation of genotoxicity in bile of carp (Cyprinus carpio) exposed to lake water treated with different disinfectants

A sensitive and rapid method to evaluate toxic and genotoxic properties of drinking water supplied from Lake Trasimeno (Umbria, Central Italy) was worked out analysing bile in Cyprinus carpio exposed for 20 d to lake water treated with 3 different disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO₂) and peracetic acid (PAA). Fish were sacrificed at 0, 10 and 20 d in order to investigate the time course of these endpoints. An aliquot of bile samples was fractionated by adsorption on C₁₈ silica cartridges and the genotoxic potential of whole bile and of bile fractions was evaluated by the single-cell microgel-electrophoresis (comet) assay on human colonic adenocarcinoma cells (Caco-2). Bile (both whole and fractionated) from specimens exposed to the three disinfectants always showed a genotoxic activity as compared to the control group. The results of this study provide evidence that all three disinfectants cause an increase in bile genotoxicity of chronically exposed fish.     

表面活化剂的联合毒性研究

通过静态试验研究了阴离子型表面活性剂LAS和非离子型表面活性剂AE对彭泽鲫的联合毒性影响。结果表明,LAS对彭泽卿的24h,48h,96h的半致死浓度LC50分别为10 20,8 73,8 43mg/L,AE对彭泽鲫的24h,48h,96h的LC50分别为87 98,72 54,68 90mg/L。LAS和AE共存对彭泽鲫联合毒性的24h,48h和96h时的相加指数AI分别为0 025,0 475,1 34,皆大于零,表现为协同作用。     

红花檵木盆景快速成型技术及规模化生产研究

本文总结了红花檵木树桩盆景快速成型制作技术流程，利用广布的檵木资源，红花檵木较强的萌芽性、一年多次抽梢及生长旺盛，以及红花檵木与檵木间极强的亲和力等特点，通过精选树桩、合理剪栽，高接换头、当年催根定植、多次摘心、促发侧枝、培养雏形、次年诱导、缠扎、修剪、第三至四年定型、出圃．为红花橙木盆景的产业化、规格化生产提供技术保证．     

云南鲤属鱼类及种质资源保存

云南野生鲤鱼种类为全国之冠。过去在渔业生产中,它们的产量曾占一定比重;现在种群数量普遍减少,亟待保护。文中讨论了种质资源保存的意义和应采取的措施。     

鄱阳湖南矶山自然保护区鲤、鲫的随机扩增多态DNA分析

利用RAPD（随机扩增多态）标记分析湖内鲤、鲫群体遗传多样性，从40个随机引物中各筛选出8个引物适合鲤、鲫群体RAPD扩增。在鲤群体中，共检测出60条带，其中多态性带42条，多态位点比率为70.00%；而在鲫群体中，共检测出61条带，其中多态性带40条，多态位点比率为65.57%。用POPGENE软件分析实验数据，结果显示：湖内鲤群体的遗传多样性水平(He=0.230 1，H0=0.391 0)和鲫群体的遗传多样性水平(He=0.218 6，H0=0.375 8)都较高，都有较大的遗传变异。而在鲤、鲫群体内，雌性群体与雄性群体相比较，其各自的遗传多样性很接近。     

两性猕猴桃株系“龙山红”的生物学特征

“龙山红”是从四川省龙门山南段的野生彩色猕猴桃中筛选出的一个两性花品种，平均单果重65．59g，可溶性固形物含量14．6％、总糖含量10．2％，果实酸甜适口，香气浓厚。果实成熟后中柱外围（即种子外侧）的果肉成淡红色，果实较耐贮运。首次发现雌雄同体且充分发育的两性花猕猴桃品种，在理论上和生产上都具有重要的意义。     

呼伦贝尔沙地核心保护区樟子松径向生长的气候响应特征

沙地樟子松是我国三北防护林工程的主要推广树种,查明该树种核心区的树木生长的气候环境制约因子,有助于提升对全球变化不利影响的适应能力,为区域生态文明建设与可持续发展提供科学数据。通过对呼伦贝尔沙地樟子松保护区核心区树轮样本的研究,揭示森林内部该树种年轮记录的生长气候响应特征。结果表明:与标准年表相比,差值年表具有更好的气候要素表征能力。水分是核心区沙地樟子松径向生长的主要限制因子,差值年表与上年8月至当年7月降水总量显著相关(0.512,p0.01)。在过去的81年中极端湿润年和干旱年分别出现15次和11次。核心区沙地樟子松差值年表具有显著的2—8年的周期信号,空间相关显示差值年表有一定的区域水文气候变化代表性。     

围封对固沙樟子松林下植被群落数量特征及多样性的影响

为揭示围封对人工樟子松固沙林林下植被群落及生态系统的影响,选择章古台围封37年生和46年生固沙樟子松林为研究对象,以邻近未围封林地为对照,采用野外调查法研究不同条件下樟子松林下植被的群落特征与物种多样性。结果表明:研究区共发现林下植被58种,分属18科42属,围封条件下促进禾本科植物与多年生植物种有所增加,多年生及灌木植物的重要值增大。围封降低先锋物种的重要值,明显增加羊草的重要值。围封有利于增加固沙樟子松林下植被群落的平均盖度、高度和生物量,而且随着围封年限的增加呈现不同程度的增长趋势;林下植被群落的物种多样性指数、优势度指数、均匀度指数在半围封5年较未围封状态略高,而在全围封10年则均低于未围封状态。因此,围封有利于樟子松林下植被群落的恢复与生长,适度的围封有利于林下群落多样性,进而保障群落的演替及生态系统稳定性的维持。