“白色污染”及其消除途径

在介绍“白色污染”的由来和发展现状的同时 ,重点就消除现有塑料“白色污染”的几种途径作了论述     

Effects of long-term land use on arbuscular mycorrhizal fungi and glomalin-related soil protein

The maintenance of soil health and productivity is a central aim of sustainable agriculture. Arbuscular mycorrhizal fungi (AMF) are soil biota fundamental for soil fertility and plant nutrition, which may be used in the evaluation of the impact of agronomic practices on soil quality. In the present study we evaluated the influence of three different land uses on AMF populations and correlated glomalin-related soil protein (GRSP) content with AMF biomass parameters, such as spore density and biovolume. Among the differently managed sites – maize monoculture, grassland and poplar grove – maize soil showed the lowest AMF spore number and GRSP content. The same morphological taxa were found in the three sites, except for one additional morphotype in poplar grove. A good correlation between GRSP and spore biovolume was found, suggesting that GRSP may represent a useful biochemical parameter for the assessment of biological soil fertility in sustainable agriculture.     

Prospects and problems pertaining to the management of arbuscular mycorrhizae in agriculture

The arbuscular mycorrhizal symbiosis is recognized for its multiple positive effects on plant growth and for its important contribution towards the maintenance of soil quality. In spite of these benefits to agriculture, at present, the realization of the full potential of this symbiosis has not yet been reached. The understanding of interactions existing among crops, fungal partners and environmental conditions must improve to allow for the efficient management of the mycorrhizal symbiosis through selected agronomic practices and inoculation of cultivated crops.     

5种白腐真菌对染料脱色降解的实验研究

使用5种白腐真菌（云芝、紫芝、韩芝、酱油曲霉和米曲霉）对活性艳红X-3B、酸性湖蓝A进行了脱色与降解实验，结果表明，共培养体系中白腐真菌对2种染料脱色降解过程中，将导致共培养液的pH、COD和吸收峰特征及A值的明显变化，变化情况也依据菌种和染料的不同而异，比较而言，紫芝对酸性湖蓝的脱色和降解效果较差，但共培养过程中共培养液颜色，从湖蓝变为蓝绿色到浅绿色，表明降解作用的真实存在，处理后的共培养液COD浓度尚难以达到排放标准，以及添加剂成本较高，是本实验研究所存在的问题。     

真菌对染料废水脱色降解的研究进展

染料属生物难降解有机物 ,染料和印染废水已成为当前最重要的水体污染源之一。本文列举了近年发现和研究的染料脱色真菌 ,并综述了真菌脱色降解染料的机理及其在染料废水处理中的应用前景     

外生菌根真菌Xerocomus chrysenteron对DDT胁迫的耐受性及酶响应研究

在纯培养条件下,研究了外生菌根真菌红绒盖牛肝菌(Xerocomus chrysenteron)对不同浓度DDT的生长效应、耐受性和氧化酶活性,测定了在DDT浓度为80.0 mg·L^-1液体培养条件下菌种生物量积累和漆酶活性随培养时间的变化. 结果表明,不同浓度DDT处理并不会改变被试菌种的生长模式,所有处理组均为典型的Logistic增长;Xerocomus chrysenteron对DDT胁迫有很好的耐受性,其半抑制浓度可达139.75 mg·L^-1;在80.0 mg·L^-1液体培养条件下,Xerocomus chrysenteron生长正常,且36 d后培养液中DDT残留率仅为初始添加量的3.5%;在高浓度DDT胁迫下,被试菌种的漆酶和过氧化物酶活性显著增强,但液体培养条件下漆酶从第16 d开始出现,36 d后培养液中漆酶活性和比活力分别达到107.24 U·L^-1和61.77 U·g-1.外生菌根真菌Xerocomus chrysenteron通过不同方式来响应DDT胁迫,显示出生物降解甚至矿化DDT的巨大潜力.     

Fungal Degradation of the Bioplastic PHB (Poly-3-hydroxy- butyric acid)

PHB (poly-3-hydroxybutyric acid) is a thermoplastic polyester synthesized by Ralstonia eutropha and other bacteria as a form of intracellular carbon and energy storage and accumulated as inclusions in the cytoplasm of these bacteria. The degradation of PHB by fungi from samples collected from various environments was studied. PHB depolymerization was tested in vials containing a PHB-containing medium which were inoculated with isolates from the samples. The degradation activity was detected by the formation of a clear zone below and around the fungal colony. In total, 105 fungi were isolated from 15 natural habitats and 8 lichens, among which 41 strains showed PHB degradation. Most of these were deuteromycetes (fungi imperfecti) resembling species of Penicillium and Aspergillus and were isolated mostly from soils, compost, hay, and lichens. Soil-containing environments were the habitats from which the largest number of fungal PHB degraders were found. Other organisms involved in PHB degradation were observed. A total number of 31 bacterial strains out of 67 isolates showed clear zones on assay medium. Protozoa, possible PHB degraders, were also found in several samples such as pond, soil, hay, horse dung, and lichen. Lichen, a fungi and algae symbiosis, was an unexpected sample from which fungal and bacterial PHB degraders were isolated.     

温度对沉水植物腐解释放DOM及微生物群落多样性的影响

在5,10,20,35℃下研究了黑藻和马来眼子菜腐解过程中DOM的特性、细菌和真菌群落结构多样性的变化.结果表明,腐解结束时5,10,20,35℃下黑藻的干物质剩余量分别为初始干物质质量的59.13%、43.91%、32.61%和29.57%,马来眼子菜的干物质剩余量分别为初始干物质质量的69.13%、51.3%、30.87%和29.57%.升高温度一定程度上促进了植物有机碳和全氮释放,对全磷无明显影响（P>0.05）.采用平行因子分析法得到黑藻中含有2种类腐殖酸组分C1、C2和1种类蛋白质组分C3,马来眼子菜中含有3种类腐殖酸组分C1、C2和C3.温度升高使得腐解水体中DO和电导率的变化程度加剧,总体上4种温度下2种植物腐解水体中DO均呈现先下降后上升的趋势.通过高通量测序得到腐解前期（0~16d）参与黑藻和马来眼子菜腐解的主要细菌分别为变形菌门（Proteobacteria）和拟杆菌门（Bacteroidetes）;腐解中后期（16~68d）参与黑藻和马来眼子菜腐解的细菌分别以厚壁菌门（Phylum Firmicutes）和变形菌门（Proteobacteria）为主,温度对细菌群落结构无明显影响,而参与2种植物腐解的真菌均以子囊菌（Ascomycetes）最为活跃.     

Rhizophagus irregularis influences As and P uptake by alfafa and the neighboring non-host pepperweed growing in an As-contaminated soil

It was documented that arbuscular mycorrhiza fungi(AMF) play an important role in protecting host plants against arsenic(As) contamination. However, most terrestrial ecosystems contain a considerable number of nonmycorrhizal plants. So far little information is available for the interaction of such non-host plants with AMF under As contaminations. By using a dual compartment cultivation system with a plastic board or a nylon mesh separating roots of non-host pepperweed from roots of the AM-host alfafa plants, avoiding direct root competition, the two plant species were grown separately or partially separated(with rhizosphere effects) in the presence or absence of the AMF Rhizophagus irregularis in As-contaminated soil. The results indicated that mycorrhiza caused phosphorus(P) concentration decrease in the non-host pepperweed, but promoted the P concentration of the AM host alfafa. Mycorrhiza is potentially helpful for non-host pepperweed to adapt to As contamination by decreasing root As concentration and showing no suppressing effect on biomass production. The study provides further evidence for the protective effects of AMF on non-host plants against As contamination, and improved our understanding of the potential role of AMF for non-host plant adaptation to As contaminated soils.     

云南会泽废弃铅锌矿区植物丛枝菌根和深色有隔内生真菌研究

用碱解离、酸性品红染色法对云南省会泽县者海镇废弃铅锌矿区的17科21种植物的丛枝菌根状况进行了调查,结果发现,15种植物形成典型的丛枝菌根,占所调查植物的71%;2种植物不确定是否形成丛枝菌根,占所调查植物的10%;4种植物没有形成丛枝菌根,占所调查植物的19%.用湿筛沉淀法从这些植物根际土壤中共分离鉴定出了4属20种丛枝菌根真菌(AMF),即无梗囊霉属(Acaulospora)4种,球囊霉属(Glomus)14种,巨孢囊霉属(Gigaspo-ra)1种,盾巨孢囊霉属(Scutellospora)1种;其中,球囊霉属分离频率为77%,是样地的优势属.在AMF中,疣突球囊霉(G.verruculosum)分离频率最高,在20种植物的根际土中都有发现;此外,聚生球囊霉(G.fasciculatum)的相对多度最大,为56%,具有最强的产孢能力.同时,在13种植物的根中发现了深色有隔内生真菌(DSE),占调查植物的62%,其中,10种植物同时被DSE和AMF感染.本调查研究表明,AMF和DSE能普遍存在于Pb、Zn重金属污染土壤中.