黄河三角洲滨海湿地的维管束植物区系特征

在2007-2008年多次实地调查并参照相关资料基础上,对黄河三角洲滨海湿地进行了植被类型划分和湿地维管束植物生态类群、生活型划分,利用统计方法分析了研究区湿地维管束植物区系的科、属构成,地理分布区成分构成.研究表明,黄河三角洲滨海湿地有71科、199属、298种维管束植物,蓼科、藜科、苋科、豆科、菊科、禾本科、莎草科等7个大科为区系主体,上述7科共76属128种,占总属数的39.38%和总种数的43.99%;区系中单种属多,属的分化程度较高.区系中有59种盐生植物、46种水生植物、44种湿生植物、144种中生植物、7种旱生植物,水生植物、湿生植物的生活型以地面芽植物、地下芽植物为主,陆地中生植物、盐生植物的生活型以一年生植物为主.从分布区类型构成来看,区系中蕨类植物区域分布成分较多,种子植物中温带分布属最多,这反映出湿地植被具有一定的地带性特征,种子植物中热带分布属、世界分布属较多分别表明海洋性气候对湿地植被特征的影响及湿地植被的隐域性特征.     

苍山花甸坝亚高山草甸植物地理区系及群落结构特征

采用样线调查法、样方调查法及文献资料分析法,获取苍山花甸坝亚高山草甸植物名录,在此基础上对该区域植物多样性、植物区系及群落结构进行分析。结果表明：1)苍山花甸坝共记录到维管植物315种,隶属于87科240属;2)种子植物科的区系以世界分布型为主(32科),无中国特有科分布,属的区系以北温带成分为主,种的温带成分则表现的更为明显,中国特有种较多;3)花甸坝草甸植物群落物种丰富度较高,特别是人为活动少及封育区的α多样性指数较高,采取保护措施可在一定程度上提高生物多样性。总体而言,花甸坝草甸生态环境保护相对较好,但应加强对生态环境及外来入侵物种的监测,及时开展生态脆弱区生态修复治理。     

重庆大木山木本植物区系及植物资源特点

基于野外调查资料,对位于三峡库区腹心地带的大木山的木本植物区系及资源特点进行研究,以期为该地区生物多样性保护和可持续利用提供依据.野外调查共发现木本植物738种,隶属于86科、288属.其中裸子植物6科、10属、15种,双子叶植物77科、271属、699种,单子叶植物3科、7属、24种.乔木268种,灌木398种,木质藤本72种.科的组成优势现象十分明显,含10种以上的科有26个,包含164属、526种植物,分别占该区木本植物总属数和总种数的56.94%和71.27%,是该区木本植物区系构成的主导成分.木本植物区系成分复杂,属的分布类型有14个,种的分布类型有12个,区系具有明显的过渡性特征.有483个中国特有种分布于该地区,占总种数的65.71%,其中27.12%的物种为华中植物区特有种.13个地区的聚类分析表明大木山与华中植物区和华东植物区关系最为密切.木本植物资源以药用、材用、观赏、食用类为主,古老孑遗植物和珍稀濒危植物丰富.图l表5参35     

云南地区中国种子植物特有属的研究

物种特有现象的研究具有重要的区系地理学和保护生物学意义。利用大尺度的植物物种分布信息,探讨了云南地区中国种子植物特有属的科、属组成,区系性质及其地理分布格局。结果表明,云南地区拥有中国种子植物特有属125属,分属于59科,共含种子植物246种,是中国种子植物特有属的重要分布地区之一。含特有属较多的科主要为菊科Compositae、苦苣苔科Gesnefiaceae、伞形科Umbelliferae、禾本科Gramineae和唇形科Labiatae。从各属所包含的物种数来看,单型属占主体地位。根据科的分布区类型构成,云南地区中国种子植物特有属主要起源于热带地区。从属的生活型构成来看,主要以草本植物属为主,而木本植物属所占比重相对较小,暗示着研究区域内特有属的区系兼有年轻成分和古老成分,但以年轻成分为主。从空间分布格局来看,特有属主要分布在“田中线”以东地区。与过去的研究结果不同,我们发现云南地区拥有3个重要的特有属分布中心和3个次级分布中心。     

青岛市城市绿地种子植物区系的构成特征

在资料分析和2013年夏秋二季进行的实地调查基础上研究了青岛市城市绿地种子植物区系的科属种构成、种的生活型构成、属的地理分布区类型构成,并比较了青岛市城市绿地种子植物区系与青岛崂山种子植物区系、中国种子植物区系属的地理分布区类型构成差异。结果表明,青岛市城市绿地种子植物区系有种子植物69科155属228种,有含5种及以上的12个较大科、124个单种属、183种木本植物和45种草本植物,有热带分布属32属、温带分布属95属、世界分布属14属和中国特有属14属。青岛市城市绿地种子植物区系有植物种类丰富多样,木本植物种类多,区系中属、种的分化程度高,属的地理分布区类型多样且具有很典型的温带特征和鲜明的中国特色等特点。     

莱州湾南岸滨海湿地维管束植物的区系特征及保护

在2003～2005年多次实地调查并参照相关资料基础上,对莱州湾南岸滨海湿地进行了植被类型划分和湿地维管束植物生态类群划分,利用统计方法分析了研究区湿地维管束植物区系较大科、属的构成,蕨类植物种的地理分布区类型、种子植物属的地理分布区类型,维管束植物区系保护面临的问题及对策.研究表明,莱州湾南岸滨海湿地植被分4个植被型、25个植物群落,由48科129属197种维管束植物构成,这些维管束植物分盐生植物,水生植物,湿生植物和中生、旱生植物4大生态类群.维管束植物区系的主体为菊科、禾本科、莎草科等含5种及5种以上的13个较大科,从维管束植物属的分布区类型构成来看,种子植物中世界分布属最多,达40属,占种子植物总属数的32%,这反映了湿地植被的隐域性特征;温带和热带分布区成分作为区系成分的主体共80属,占种子植物总属数的64%.盐田、养殖池、道路建设,海岸侵蚀,地下咸、卤水入侵,气候干旱,河流断流等自然、人为原因导致莱州湾南岸滨海湿地退化,植被发生退化演替,区系中一些珍稀濒危植物受到日益严重的威胁.提出了对退化湿地进行生态恢复与重建,推广生态旅游、生态养殖等可持续的滨海湿地利用方式,建设湿地自然保护区和生态环境监测网络等莱州湾南岸滨海湿地维管束植物区系保护对策.     

井冈山猴头杜鹃群落特征的研究

以井冈山猴头杜鹃（Rhododendron simiarum）群落5个样地调查资料为基础,对该群落的物种组成、区系成分、群落结构和物种多样性进行了研究,结果表明：群落有维管植物30科43属50种,其中蕨类植物有5科6属6种,裸子植物4科4属4种,被子植物21科33属40种。区系分析显示该植物区系起源古老,地理成分复杂,以热带性成分为主,温带性成分占有一定的比例。群落为复层异龄结构,猴头杜鹃、甜槠（Castanopsis eyrei）、福建柏（Fokienia hodginsii）、台湾松（Pinus taiwanensis）、薯豆（Elaeocarpus japonicus）和白豆杉（Pseudotaxus chienii）为群落的建群种。除Pielou指数外,群落物种多样性指数较低,各样地间多样性指数测值变幅较大;测度猴头杜鹃群落物种多样性时,各种多样性指数基本表现出相同的趋势;总体来看,猴头杜鹃群落物种多样性在群落不同层次的变化规律为：灌木层〉乔木层〉草本层。     

莆田老鹰尖自然保护区森林群落物种多样性的研究

对福建莆田市老鹰尖植物区系和群落物种多样性的调查与分析,结果表明,老鹰尖植物种类丰富,计有维管束植物181科737属1003种(含变种),其中蕨类植物35科72属89种,裸子植物9科18属19种,被子植物137科647属901种;植物区系成分复杂,联系广泛,以热带亚热带成分为主,属、种分别占55.17％和57.48％,其植被为中亚热带向南亚热带过度类型;11个主要森林群落的物种多样性以米槠林为最高,D_(ah)达3.5109,其次为罗浮栲+丝栗栲林和米槠+栲树林,D_(ah)指数值分别达2.8945和2.7854,而篓竹林群落为最低,D_(ah)指数值仅1.0081,群落各层片物种多样性以灌木层为最高,呈灌木>乔木层>草本>藤本的变化趋势,说明老鹰尖的水热资源较为丰富。     

湖南省特有植物的分布

湖南省特有植物共计235种(含种下等级;下同),归110属52科,其中蕨类植物25种,裸子植物3种,被子植物207种(双子叶植物和单子叶植物各计125和82种),主要集中于Theaceae,Rosaceae,Dryopteridaceae,Urticaceae,Ericacaeae,Gesneriaceaea,Labiatae(=Lamiaceae)和Gramineae(=Poaceae)等8科,共计155种,占全省总特有种数的65.96%.湖南特有植物所归的属的分布区类型以北温带,热带亚洲,泛热带及中国特有成分为主,分别占总数的20.00%,19.09%,13.64%和13.64%.从水平分布上看,湖南省特有植物主要分布于西北部,计77种,占全省总特有种数的32 17%;其次是西南部与南部,各有51和50种,分别占全省总特有种数的21.70%和21.28%,从垂直分布上看,它们主要分布于中山地带(海拔800-1 600m),计108种,占全省总特有种数的45.80%;其次是低山地带(海拔300-800m),计84种,占全省总特有种数的35.88%。     

双台河口自然保护区滨海湿地的维管束植物区系特征

辽宁双台河口自然保护区滨海湿地维管束植物区系中有56科117属155种维管束植物,有蔷薇科、菊科、禾本科、蓼科、豆科、唇形科、香蒲科、眼子菜科、莎草科等9大科51属76种,9大科的属数、种数占区系总属数和总种数的43.59%、49.03%;区系内小科、单种属多,说明科、属的分化程度较高。区系中有15种盐生植物、25种水生植物、34种湿生植物、79种中生植物和4种旱生植物,湿地植被的优势种和建群种均为盐生植物、水生植物和湿生植物,这表明保护区内滨海湿地植被的形成不仅受海水、土壤盐渍化影响,更受辽河径流淡水的影响。区系中有地面芽植物、地下芽植物72种,占总种数的46.45%,说明冷湿气候对保护区内滨海湿地植被的形成有重要作用。区系中有世界分布属31属,占区系总属数的26.50%,这反映了湿地植被的隐域性;有温带分布属57属、热带分布属23属,分别占区系总属数的48.72%、19.66%,这分别表明保护区滨海湿地植被具有一定的地带性特征,雨量充沛、冬季气温较高的海洋性气候特征对湿地中起源于热带的维管束植物生存限制较小。     

Applications of chitosan in food,pharmaceuticals, medicine,cosmetics, agriculture,textiles, pulp and paper,biotechnology, and environmental chemistry

Environmental Chemistry Letters - Chitosan is a biopolymer obtained from chitin, one of the most abundant and renewable materials on Earth. Chitin is a primary component of cell walls in fungi, the...     

Fragmentation of Phragmites Habitats, Minimum Viable Population Size, Habitat Suitability, and Local Extinction of Moths, Midges, Flies, Aphids, and Birds

Results from populations of insects and birds inhabiting Phragmites habitats were used to analyze effects of fragmentation. Flush-crash cycles of the stem-boring moth Archanara geminipuncta (Lepidoptera, Noctuidae) showed regionally concurrent, local extinctions despite an originally enormous population size (more than 180,000 adults), emphasizing the importance of metapopulation dynamics. Further, A. geminipuncta could be considered a keystone species, since shoot damage facilitated more than twenty species of herbivores, saprovores (of the caterpillars' feces), and their parasitoids. The gall midge Lasioptera arundinis could survive only in side shoots induced by shoot damage of A. geminipuncta .
Small Phragmites stands had thinner shoots (due to a water or nutrient deficiency) and shoots with more leaves (due to a better light supply) than large stands, thereby influencing species-specific demands for habitat suitability and nutritiousness of reed tissue. In other words significance of habitat fragmentation could not be assessed by area alone. For example, two chloropid flies depending on thin, yellowish shoots survived only in small habitats or in the unmown edges of large habitats.
Local persistence of Phragmites herbivores depended on much larger population sizes than could be expected from a population size sufficient to maintain genetic variation. At least 11,000 adults of the gall midge Giraudiella inclusa (or more than 84,000 galls) were necessary to avoid local extinction.
With regard to conservation management of reed habitats, nature reserves should consist of old and unmown reeds, have fewer disturbed (particularly, fewer mown) habitat edges, measure more than two hectares (priority should go to the largest remaining fragments), and be surrounded by nearby reed habitats providing reservoir populations and diverse shoot types.     

Metal passivity as mechanism of metal carcinogenesis: Chromium,nickel, iron,copper, cobalt,platinum, molybdenum

For the transition metals chromium, nickel, iron, copper, cobalt, platinum, and molybdenum, mechanisms of stable bonding in biochemistry (emphasis on carcinogenic mechanisms), chemistry, industrial chemistry, as well as epidemiological, occupational, orthopedic (implant devices) effects related to carcinogenesis, were reviewed. Hypothetically, the propensity to stable bonding (inertness), which ensures the metals’ performance capacity for consumers and industrial application, relates to their carcinogenicity. For chromium, a relationship between industrial/chemical and biological reactivity was noted for the tendency of Cr(III) ions to cause hydrolysis previous to stable bonding, as occurs during anodic passivation, leather tanning, and as indicated in biochemical studies pertaining to a mechanism of DNA condensation, which was suggested as a carcinogenic mechanism. The involvement of metal hydrolysis in both anodic passivation and biochemistry was noted also for nickel, iron, and platinum; the DNA interaction of platinum (cis-platin) is known to depend on hydrolysis. For nickel, issues of potential (V) were found important in both passivation and carcinogenicity. Comparably, the passivity behavior of cobalt and copper was found atypical, and their carcinogenicity yet unclear. Molybdenum, contained in passivated metallic implants, may relate to implant-associated carcinogenesis. Occupational carcinogenic effects were indicated for chromium, nickel, iron, and cobalt as caused by both reactive and passivated metal species. Exposure to acids and chronic respiratory irritation/infection/inflammation in workers were important cofactors in metal carcinogenesis. For wood and leather workers exposed to dust, the assumed presence in dust of metal particles abraded from alloys (sawing or cutting blades) may be a carcinogenic exposure hazard.     

Lead,cadmium, copper,zinc, iron,and calcium in human hair as a function of gender,age, smoking,and hair dyeing

Hair samples were collected randomly from 110 subjects (55 male and 55 female) ranging in age from (<15–60) years. Each subject was asked to complete a personal questionnaire describing his/her sex, age, general health, smoking, use of hair dyes, occupational area, and living habits. Concentrations of Pb, Cd, Cu, Zn, Fe, and Ca in human hair samples were evaluated using atomic absorption spectrometry. Results indicated that concentrations of Pb, Cd, Cu, and Zn in the hair of smokers were higher than those in the hair of non-smokers, whereas, Fe and Ca concentrations in hair of smokers were lower than those in hair of non-smokers. Moreover, the concentrations of these elements are higher in dyed hair compared with undyed hair.     

Concentrations of V,Cr, Mn,Fe, Ni,Co, Cu,Zn, As and Cd in mesopelagic crustaceans from the North East Atlantic Ocean

Specimens of oceanic decapods, mysids and euphausiids, collected from the North East Atlantic Ocean during July 1985, were analysed for V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As and Cd. Measurement of the metals was carried out using two techniques: inductively-coupled plasma-source mass spectrometry (ICP-MS) and atomic absorption (AAS). With the exception of the iron data, good agreement was observed between the data from the two techniques. Baseline-metal data are presented for the species measured, along with any effects of animal size on metal concentration. The data presented for oceanic animals from different trophic levels are important in studies of metal fluxes and for the assessment of markers within the food web in the oceans.     

Fractionation of trace metals (Mn,Zn, Cu,Pb) in Red Sea sediments,Gulf of Aden,Yemen

A sequential extraction technique was applied to estimate the chemical association of Mn, Zn, Cu and Pb in five chemical phases (exchangeable, carbonate, Fe–Mn oxides, organic matter and residual) in sediments of the Gulf of Aden, Yemen. The results indicated that a higher level of Mn was associated with the residual fraction (natural sources) than the non-residual fraction (anthropogenic sources). Zn fractionations revealed that it was associated more with Fe–Mn oxides and organic fractions than exchangeable and carbonate fractions. Most of the Cu was present in the residual form (60–72%) except for in the main port area (zone III), where it was associated with the organic phase (77% of the total Cu content, the organic matter content was 5%). Similarly, most Pb was bound in the residual fraction (56–71%) except the main port area where ～ 62% of the total Pb was bound in non-residual fractions. It was also found that the Pb concentration in the exchangeable fraction was very high compared with other metals. The risk assessment code for the metals showed a low risk for Zn and Cu, but low to medium risk for Mn. Fractionation of Pb showed medium risk at most of the regions except at the eastern area, which revealed a high risk for the aquatic environment.     

Research progress on distribution,sources, identification,toxicity, and biodegradation of microplastics in the ocean,freshwater, and soil environment

• Microplastics are widely found in both aquatic and terrestrial environments. • Cleaning products and discarded plastic waste are primary sources of microplastics. • Microplastics have apparent toxic effects on the growth of fish and soil plants. • Multiple strains of biodegradable microplastics have been isolated. Microplastics (MPs) are distributed in the oceans, freshwater, and soil environment and have become major pollutants. MPs are generally referred to as plastic particles less than 5 mm in diameter. They consist of primary microplastics synthesized in microscopic size manufactured production and secondary microplastics generated by physical and environmental degradation. Plastic particles are long-lived pollutants that are highly resistant to environmental degradation. In this review, the distribution and possible sources of MPs in aquatic and terrestrial environments are described. Moreover, the adverse effects of MPs on natural creatures due to ingestion have been discussed. We also have summarized identification methods based on MPs particle size and chemical bond. To control the pollution of MPs, the biodegradation of MPs under the action of different microbes has also been reviewed in this work. This review will contribute to a better understanding of MPs pollution in the environment, as well as their identification, toxicity, and biodegradation in the ocean, freshwater, and soil, and the assessment and control of microplastics exposure.