多群落双向驱动协作搜索算法

针对复杂优化问题中数据混杂多变的特点,提出一种能够根据环境变化不断优化种群适应度的多群落双向驱动协作搜索算法。该算法在分析微粒群落特性的基础上,基于无向加权图建立了多群落协作网演化模型,该模型依据群落适应值的优劣程度对群落类型进行划分,并根据不同群落间的协作权重和群落节点响应度评估群落节点强度,由节点强度最大的群落引导整个协作网进化,改进传统群集智能算法面对复杂优化问题中环境变化的自适应性能缺陷;构建了一种多群落双向驱动的进化新模式,给出了多群落协作的异步并行搜索算法,实现了不同环境下群落内部与群落之间的并行进化,降低了数据分析中巨大的计算时空开销。实验结果表明,该方法面向混杂多变数据不断优化种群适应度,能够较快地适应环境变化,并在可接受的时间内得到精确解,为复杂优化问题的求解提供了有效手段。

美姑县的多群落耕作制

美姑县地处大凉山腹心地区,是一个彝族聚居县,海拔高度范围640～4035米。境内山高坡陡,气候多样,“一山有四季,十里不同天”。土层瘠薄,灌溉不便。干旱、洪涝、冰雹等自然灾害十分频繁。解放前,在奴隶制度的束缚下,生产力极其低下,处于烧山垦地,丢荒轮息,广种薄收的原始状态。解放后,农业生产有了巨大发展,尤其是在党的十一届三中全会以来,连续十一年粮食生产持续稳定增长。

基于多群落协作进化算法的配电物联网节点优化部署

针对配电物联网节点部署覆盖率低、感知可靠性差和部署成本最优化的问题,提出了一种基于多群落协作进化算法的配电物联网节点优化部署方法。在分析配电物联网节点部署关键影响因素的基础上,构建了包括节点部署成本和节点覆盖率的配电物联网节点部署优化评价指标体系,建立了节点部署的全局优化数学模型,并采用多群落协作进化算法进行群落内与群落间的异步并行优化,提升了对于配电物联网节点优化部署问题的适应能力,最后通过试验证明所提方法的有效性,为配电物联网节点优化部署提供了新的思路和方法。

分布式科技资源多服务任务优化调度

为了解决分布式环境下科技资源服务过程并发服务访问不确定性高,按需服务实体产业分配不均衡的问题,提出一种基于多群落协作搜索的启发式任务调度策略。在分析科技资源服务调度过程及特点的基础上,搭建了考虑分布式科技资源并发服务访问不确定性和资源分配不均衡性的多服务任务优化调度模型;给出该调度模型的多群落双向驱动进化算法,并采用二进制对粒子的速度和位置进行编码,通过重构粒子表达式完成粒子群算法到离散空间的映射,同时建立不同粒子群落之间的交互进化机制以增强种群的多样性,进而提高算法对搜索环境的适应能力和求解精度。以汽车发动机故障诊断维修资源服务任务调度过程为例,验证了所提方法的有效性,为复杂调度问题的求解提供了有效手段。

Diversity of Sucking Lice on Small Mammals in the Surrounding Areas of Erhai Lake in Yunnan,China

An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were captured and identified into 7 families, 15 genera and 21 species in 4 orders （Rodentia, Insectivora, Scandentia and Carnivora）, while t4 635 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 5 families, 6 genera and 21 species in the Order Anoplura, The sites stand alongside three cordilleras surrounding the Erhai Lake, namely Eastern Wuliang Mountain, Southern Ailao Mountain and Western Cangshan Mountain. The three confined oriented areas are different landscapes within the same zone where the longitude, latitude, altitude and fauna are homologous but isolated by Erhai Lake as inartificial barrier. The aim of this study was to recognize features of the species diversity, abundance, community structure, similarity and distribution of sucking lice in different landscapes within the same zone. The results showed the species diversity of sucking lice was very low with a very simple community structure. The distribution of sucking lice and their corresponding hosts are quite uneven among different oriented areas and this may imply that ecological environment influences the species composition and distribution of sucking lice and their corresponding hosts. A certain species of hosts usually have their fixed louse species. The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. Species of sucking lice on the same small mammal host in different oriented areas of Erhai Lake are homologous. The results strongly suggest a close relationship of co-evolution between sucking lice and their hosts.

Seasonal dynamics of wintering waterbirds in two shallow lakes along Yangtze River in Anhui Province

The shallow lake wetlands in the middle and lower Yangtze River floodplain are important wintering and stopover habitats for migratory waterbirds on the East Asia-Australia Flyway.With increasing fishery practices in recent years,however,the wetlands have deteriorated significantly and now threaten wintering waterbirds.To gain insight into the influence of deteriorating wetlands on waterbirds,we conducted a survey of wintering waterbird species,population size,and distribution across 11 belt transects in Caizi Lake and Shengjin Lake,two shallow lakes along the Yangtze River in Anhui Province from November 2007-April 2008 and from November 2008-April 2009,respectively.The impacts of different fishery patterns on the distribution of waterbirds were also analyzed.A total of 43 waterbirds species belong to 7 orders of 12 families were counted during the surveys,of which 38 were found in Caizi Lake with a density of 8.2 ind./hm2,and 42 in Shengjin Lake with a density of 3.5 ind./hm2.Geese（Anser cygnoides）,bean geese（Anser fabalis）,tundra swan（Cygnus columbianus）,and dunlin（Calidris alpina） were the dominant species in the two shallow lakes.Species number and individual assemble reached maximum at the end of December and in early January of the following year,without coincidence of the largest flock for different ecological groups.Based on waterbird diversity across the 11 belt transects and the fishery patterns,habitats could be divided into three groups.Gruiformes,Anseriformes and Charadriiformes had relatively higher densities in the natural fishery zones and lower densities in the cage fishery zones;whereas,the density of Ardeidae showed little change across all lake zones.It is important to develop sustainable fishery patterns in shallow lakes along the middle and lower Yangtze River floodplain to better protect resources of wintering waterbirds.

Distributional patterns of species diversity of main plant communities along altitudinal gradient in secondary forest region,Guandi Mountain,China

Fourteen plots were chosen along with the altitude of 1600-2600 m in Guandi Mountain, Shanxi Province, China to investigate all the trees in the plots, and the species diversity indexes were calculated for analyzing the effects of altitudinal gradient on plant species diversity. The results showed that the order of dominant species from low altitude to high altitude is as Quercus liaotungensis Koidz, Pinus tabulaeformis, Betula platyphylla, B. albo-sinensis, Picea wilsonii, P. Meyeri and Larix principis-rupprechtii. With altitude increasing, the average height and DBH of the arbor firstly increase and then decrease, the maximal height and DBH of the arbor present the unimodal variable trend, the maximal height of coniferous and broad-leaved trees firstly increases and then decreases, the maximal DBH of broad-leaf trees has no clear fluctuation, and the maximal DBH of the needle-leaf trees decreases gradually. Moreover, in middle altitudinal communities （the altitude of 1900-2200 m）, the maximal height and DBH of the needle-leaf trees are larger than these of broad-leaf trees. Both Shannon-wiener index and Margalef index of the communities present the unimodal variable trend, with a peak in the mid-altitude. Plant species diversity in the mid-altitude （1900-2200 m） is higher than that of the low altitude （1600-1900 m） and the high altitude （2200-2600 m）. In addition, the unimodal variable trend of α species diversity is clearly correlated with the altitudinal gradient. The change of plant species diversity is significantly correlated with the altitudinal gradient, and also related to the community structure, the community composition, the feature of species and the human disturbance.

Species and Diversity Analysis of Flower-visiting Insects of Asian Sacred Lotus in Jiangxi, Hunan and Hubei Provinces

[Objective]This study aimed to investigate the community structure, species and quantities of flower-visiting insects of seed lotus in main producing ar-eas of Jiangxi, Hunan and Hubei provinces. [Method] Using sample area survey and netting method in the fixed points to investigate species and quantities of Asian sacred lotus, the species diversity of different locations was evaluated by diversity indices （H′）, evenness indices （J） and dominant concentration indices （C）. [Result] Apis mel ifera, Apis cerana cerana, Xylocopa （Koptortosoma） sinensis, Xylocopa （s.str.） valga and Xylocopa （Al oxylocopa） appendiculata, al of which belong to order Hy-menoptera were the main pol inators of lotus. Temperature was the main factor which influenced the foraging behaviors of flower-visiting insects. The daily activities of X. （s.str.） valga and X. （Al oxylocopa） appendiculata were bimodal, and that of A. mel-lifera, A. cerana cerana and X. （s.str.） valga were unimodal. The percentage of wild pol inators in Linxiang of Hunan Province and Xianning of Hubei Province were only 20.59% and 3.90% respectively, and there were six species of flower-visiting insects in Linxiang and three in Xianning. The percentages of wild pol inators in Shicheng of Jiangxi Province and the lotus garden in Huazhong Agricultural University were 55.61% and 90.40% respectively, and the flower-visiting insects belonged to 13 and 12 species respectively. The diversity index （H′） and evenness index （J） were listed here in a decreasing order： Shicheng of Jiangxi ＆gt;lotus garden in Huazhong Agricul-tural University＆gt;Linxiang of Hunan ＆gt;Xianning of Hubei. The sequence of dominant concentration indices （C） was Shicheng of Jiangxi ＆lt;the lotus garden in Huazhong Agricultural University＆lt;Linxiang of Hunan＆lt;Xianning of Hubei. The diversity indices （H′）, evenness indices （J） and dominant concentration indices （C） of each sample location were consistent. [Conclusion] The species and quantities of Asian sacred lotus vary in different ecological areas. The species and quantities of Linxiang in Hunan Province and Xianning in Hubei Province are rare. The increase of lotus production must depend on bee pol ination.

Community Structure and Diversity Distributions of Small Mammals in Different Sample Plots in the Eastern Part of Wuling Mountains

Five years＇ （2000-2004） continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the eastern part of the Wuling Mountains, south bank of the Three Gorges of Yangtze River in Hubei. A total of 29 297 rat clamps/times were placed and 2271 small mammals such as rodents were captured, and 26 small mammals were captured by other means. All the small mammals captured belonged to 8 families 19 genera and 24 species, of which rodentia accounted for 70.83% and insectivora 29.17%. Through analysis of the data, the results showed that： 1 ） although the species richness had a trend of increasing along different sample plots as altitude increased from south to north, quite a few species showed a wide habitat range in a vertical distribution （ 15 species were dispersed over three zones and two species over two zones） , indicating a strong adaptability of small mammals such as rOdents at lower altitudes in most areas and comparatively less vertical span of entire mountains; 2） whether in seven different sample plots or six different ecological types, Apodemus agrarius and Rattus norvegicus were dominant species below 1200m, and Anourosorex squamipes, Niviventer confucianus and Apodemus draco were dominant above altitudes of 1300m, however, in quantity they were short of identical regularity, meaning they did not increase as the altitude did, or decrease as the ecological areas changed; 3）the density in winter was obviously greater than that in spring, and the distribution showed an increasing trend along with altitude, but the density in different sample plots was short of identical regularity, showing changes in different seasons and altitude grades had an important impact on small mammals such as rodents; 4） in species diversity and evenness index, there were obvious changes between the seven different sample plots, probably caused by frequent human interference in this area. Comparatively speaking, there was less human interference at high altitudes where vegetation was rich and had a high diversity and evenness index, and the boundary effect and community stability were obvious. Most ecological types have been seriously interfered with due to excessive assart at low altitudes with singular vegetation and low diversity and evenness index and poor community stability, showing an ecosystem with poor anti-reversion. If human interference can be reduced in those communities at high altitudes with low diversity and evenness index, the biological diversity in the communities will gradually recover to similar levels of other ecological areas.

Impacts of Environmental Factors on the Structure Characteristics of Avian Community in Shanghai Woodlots in Spring

From March to May, 2004, we selected 8 typical parks or green lands in Shanghai downtown as the study sites to conduct a ornithological research. During this study, total 55 species of birds were recorded, which included 31 resident and 24 migratory species. With statistics methodology, we analyzed the avian communities with 10 major environmental factors covering the park area, water percentage, vegetation species, canopy cover, shrub cover, grass cover, hill number, location condition, human quantity, path width, the study results indicated that: (1) the following 7 environmental factors were important to impact the structures of the avian community, they were park area, vegetation species, shrub coverage, grass coverage, hill number, location condition of the parks and path width; (2) the avian community of theses urban parks tended to deteriorate in the bird number and diversity; the man-made lake which was currently promoted in the park designing and planning process would not be good to attract the birds.

Advances in Research on the Structure and Diversity Variation of Insect Communities in Wetland

The species diversity, structure and dynamic rules of insect communities in wetland can provide data of the insects for the protection, utilization and monitor- ing of wetland, which is an essential link to maintain the healthy ecological system of the wetland and protect the biodiversity in the wetland. A systematic study on the composition and succession of insect communities in the wetland, as well as the indication of insect groups can provide a theoretical basis for wetland protection and management, and thus promote the development of regional economy and en- vironmental protection.

Screening of Preprocessing Method of Biolog for Soil Microbial Community Functional Diversity

As one of the main methods of microbial community functional diversity measurement, biolog method was favored by many researchers for its simple oper- ation, high sensitivity, strong resolution and rich data. But the preprocessing meth- ods reported in the literatures were not the same. In order to screen the best pre- processing method, this paper took three typical treatments to explore the effect of different preprocessing methods on soil microbial community functional diversity. The results showed that, method B＇s overall trend of AWCD values was better than A and C＇s. Method B＇s microbial utilization of six carbon sources was higher, and the result was relatively stable. The Simpson index, Shannon richness index and Car- bon source utilization richness index of the two treatments were B〉C〉A, while the Mclntosh index and Shannon evenness were not very stable, but the difference of variance analysis was not significant, and the method B was always with a smallest variance. Method B＇s principal component analysis was better than A and C＇s. In a word, the method using 250 r/min shaking for 30 minutes and cultivating at 28 ℃ was the best one, because it was simple, convenient, and with good repeatability.

滨海盐碱土壤可持续修复研究进展

滨海盐碱土壤广泛存在于我国东部沿海区域,占所有盐碱土壤面积的比例约1/3。由于水盐运动,所以,长期撂荒下的盐碱土壤造成土地进一步荒废,严重制约区域景观、农业、经济发展。现阶段,基于见效快,效率高等目的,常见有客土置换、熟石灰"井灌井排"、原位及异位淋洗法等修复方法。常见传统修复方式虽然能够在短期内改善土壤盐碱化程度,却更易造成二次污染,且修复后的土壤需要进行长期人工维护与保养。从可持续修复手段出发,基于发挥修复材料本身长时效特性,旨在减少修复过程中的物料与人力成本,提高修复后的土壤自净能力。同时,亦针对可持续修复手段内核做出阐述,以期为受盐碱化危害的滨海滩涂区域做出具有意义的指导和科学示意。

Macrobenthos Community Structure and Its Relations With Environmental Factors in Three Reservoirs in Tianjin

[Objective] The aim was to research macrobenthos community structure and its relations with environmental factors in three reservoirs. [Method] Benthic diversity and water quality of Yuqiao Reservoir, Beidagang Reservoir and Er- wangzhuang Reservoir were investigated in May, July and September 2011, respec- tively. []Result] Of all the 14 sampling sites, 22 species of macroinvertebrates were collected, totally, which included 6 species of aquatic insects, 7 species of Mollusca, 2 species of Crustacean, 7 species of Oligochaeta. The species of macroinverte- brates during May, July and September in Yuqiao reservoir were 11, 8 and 10, respectively. The dominant species were Chironomus sinicus, and Monopylephorus limosus. The average density and biomass of the macrobenthos were 132.43 ind./m2 and 50.09 g/m2. Yuqiao reservoir was mostly at status of premediate polluted, according to the Margalef index, Shannon index and Pielou index. The species of during May, July and September in Beidagang reservoir were 5 5 and 5, respectively. The dominant species were Chironomus sinicus, Penaeus vannamei. The average density and biomass of the macrobenthos were 218 ind./m2 and 2.70 g/m2. Beidagang reservoir was mostly at status of heavy polluted, accord- ing to the Margalef index, Shannon-wiener index, Pielou index. The species of during May, July and September in Erwangzhuang reservoir were 3, 5 and 5, respectively. The dominant species were Monopylephorus limosus, Chi- ronomus sinicus. The average density and biomass of the macrobenthos were 104 ind/m2 and 0.20 g/m2. Erwangzhuang reservoir was mostly at status of intermediate polluted, according to the Margalef index, Shannon index, Pielou index. The density of zoobenthos in Yuqiao Reservoir was positively significantly correlated with TP （P〉 0.05）, negatively correlated with NH4＋-N （P〉0.05）, positively correlated with COD （P〈 0.01）, not significantly correlated with other environment factors （P〉0.05）. There was no significant correlation between biomass of zoobenthos and environment factors. The density of zoobenthos in Beidagang Reservoir with NH4＋-N was positively signif- icantly correlated （P〈0.05）, not significantly correlated with other aquatic environment factors （P〉0.05）. There was no significant correlation between biomass of zoobenthos and environment factors. The density of zoobenthos in Erwangzhuang Reser- voir with NO3-N was positively significantly correlated （P〈0.05）, not significant cor- related with other aquatic environment factors （F〉0.05）. The biomass of zoobenthos in Erwangzhuang Reservoir with NH4＋-N was positively significantly correlated （P〈 0.05）, not significant correlated with other aquatic environment factors （P〉0.05）. [Conclusion] It is indicated that this three reservoirs were all eutrophied and polluted, and the eurephication extent change of water in three reservoirs is as follows： Beidagang reservoir〉Erwangzhuang reservoir〉Yuqiao reservoir.

Patterns of species diversity and functional diversity of breeding birds in Hangzhou across an urbanization gradient

Given the rapid rise in human population and increasing urbanization,it is important to understand their potential impacts on biodiversity.From March 2007 to August 2007,we conducted bird surveys in 90 strip transects,each 3 km long and 100 m wide,along a gradient of urbanization in Hangzhou,China.This gradient spanned a range of urbanization levels including urban areas,rural-urban continuum areas,farming areas,mixed forest/farming areas and forested areas.We recorded 96 breeding bird species and classified them into nine functional groups based on nesting requirements.The nine functional groups consisted of canopy nesters,shrub nesters,canopy/shrub nesters,natural cavity nesters,building nesters,natural cavity/building nesters,ground nesters,water surface nesters and parasitic nesters.Species and functional diversities were estimated based on the Shannon-Wiener index.Environmental data of each transect as human disturbance,vegetation cover and building index were also measured,and a synthetic urbanization index of each transect was introduced based on these data.We used regression analyses to model the relationship of species abundance,species diversity,functional abundance and functional diversity with this synthetic index.The results show that urbanization significantly reduces species richness,species diversity,functional richness and functional diversity,but the specific patterns differed.The relationship between species abundance/species diversity and urbanization is linear.In contrast,the relationship between functional diversity and urbanization was quadratic.In other words,with increased urbanization,functional diversity declined only slightly at first but then dropped at an accelerating rate.This implies that,although moderate urbanization reduces species diversity of breeding birds,it affects functional diversity of breeding birds only slightly in Hangzhou.The regression analysis of species diversity and functional diversity suggests a quadratic relationship between species diversity and functional diversity,i.e.,a linear relationship between species diversity and functional diversity can only exist at low diversity levels across urbanization gradients and increasing species abundance does not lead to an increase in functional diversity at the highest diversity levels.

Characteristics of Phytoplankton and Its Correlation with Water Environment in SFTWs

[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,phytoplankton＇s community structure,diversity index and their correlation with water purification performance were investigated. [Result] 57 species of seven phylum of phytoplankton were detected in this tested river,including 12 species of Cyanophyta,2 of Cryptophyta,10 of Bacillariophyta,1 of Xanthophyta,7 of Euglenophyta,1 of Pyrrophyta and 24 of Chlorophyta,respectively. Additionally,it was found that Cyanophyta was the dominant phytoplankton,followed by Bacillariophyta and Cyanophyta. Biological density was far more than 10×105 ind./L,thus it could be considered that the river was eutrophic. The range of Shannon-Wiener index was 0.6-2.2,Pielou index was 0.5-2.5 and Margalef index＇s range was 0.35-0.85,which could further prove that the water was eutrophic. The biological density and species were significantly positively correlated with temperature and N content,indicating that the absorption of N by phytoplankton was the main N-removal pathway in SFTWs. [Conclusion] This study had provided basis for the river regulation and ecological restoration.

The Influence of Plant Diversity and Functional Composition on Ecosystem Stability of Four Stipa Communities in the Inner Mongolia Plateau

The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner Mongolia Plateau. The research work was based on a 12-year study (from 1984 to 1995) of species abundance, diversity, and primary productivity of four Stipa communities, i.e. S. baicalensis Roshev., S. grandis P. Smirn., S, krylovii Roshev., and S. klemenzii Roshev. respectively. The Shnnon-Wiener index was used as a measurement of plant diversity, while functional composition was used to differentiate the functional groups that were included in the communities. The plant species of four Stipa communities were classified into functional groups based on the differences in life forms and ecological groups, which influence their performance in resource requirements, seasonality of growth, tolerance to water stress, and life history. Plant species were classified into five functional groups based on their differences in life form, shrubs and half shrubs, perennial bunch grasses, perennial rhizome grasses, forbs, annuals and biennials. Based on their differences in water requirement these species were classified into four functional groups: xerads, intermediate xerads, intermediate mesophytes, and mesophytes. The results showed: 1) Plant species diversity stabilized ecosystem processes. Shannon-Wiener index were 2.401 4, 2.172 0, 1.624 8, 0.354 3 from S. baicalensis community to S. grandis, S. krylovii and S. klemenzii community, respectively. The dynamics of the aboveground net primary productivity (ANPP) for a 12-year's period showed a reverse pattern, the coefficients of variation of the four communities were 21.94%, 20.63%, 29.21% and 39.72% respectively. 2) The Life form functional group component of diversity was a greater determinant of the ecosystem processes than the species component of diversity. The effects of perennial bunch grasses, perennial rhizome grasses and forbs on community stability were highly significant. 3) The ecological group component of diversity was also a great determinant of the ecosystem processes. The effects of xerads, intermediate xerads, and mesophytes on community stability were also very strong.

Research on Species Diversity Characteristics of Chinese Endemic Plant Populus shanxiensis

[Objective] This study aimed at researching the species diversity of Populus shanxiensis community in Heichashan Mountain. [Method] Based on sampling methods, investigation in sampling spots was carried out according to the important indicator, the abundance index （N0）, Simpson index （λ）, Shannon-Weiner index （H＇） and homogeneity index （E1 and E5） were used for analysis. [Results] Species diversity index of Populus shanxiensis community was not only depended on the species compositions of communities, but also closely related to the important value of species. The order of abundance index and diversity index in each layer of Populus shanxiensis community was herb layershrub layertree layer, and the abundance index was positively related to the diversity index; while the variation trend of community homogeneity index was different from that of abundance index and diversity index, and the homogeneity had shown negative correlation with the dominance. [Conclusion] In this study, the growth status and conditions of Populus shanxiensis were further understood and researched, which had laid theoretical foundation for protecting the endangered species and provided basic information for the future studies of endangered species and related disciplines.

Epiphytic bacterial communities on two common submerged macrophytes in Taihu Lake: diversity and host-specificity

Leaves of terrestrial and aquatic plants are home to a wide diversity of bacterial species. However, the diversity and variability of epiphytic bacteria on their submerged plant hosts remains poorly understood. We investigated the diversity and composition of epiphytic bacteria from two common submerged macrophytes: Vallisneria natans and Hydrilla verticillata in Taihu Lake, Jiangsu, China, using methods of terminal restriction fragment length polymorphisms (T-RFLP) and clone library analyses targeted at bacterial 16S rRNA genes. The results show that: (1) the libraries of the two waterweeds contain wide phylogenetic distribution of bacteria, and that the sequences of the two libraries can be separated into 93 OTUs (at 97% similar value); (2) Betaproteobacteria, including Burkholderiales, was the most abundant bacterial group on both plants. Cyanobacteria and Gammaproteobacteria were the second largest groups on V. natans and H. verticillata, respectively. Both clone libraries included some sequences related to those of methanotrophs and nitrogen-fixing bacteria; (3) Cluster analysis of the T-RFLP profiles showed two distinct clusters corresponding to the two plant populations. Both ANOSIM of the T-RFLP data and Libshuff analysis of the two clone libraries indicated a significant difference in epiphytic bacterial communities between the two plants. Therefore, the epiphytic bacterial communities on submerged macrophytes appear to be diverse and host-specific, which may aid in understanding the ecological functions of submerged macrophytes in general.

Changes of Bacterial Community Structure in Copper Mine Tailings After Colonization of Reed (Phragmites communis)

Soil samples were collected from both bare and vegetated mine railings to study the changes in bacterial communities and soil chemical properties of copper mine tailings due to reed （Phragmites communis） colonization. The structures of bacterial communities were investigated using culture-independent 16S rRNA gene sequencing method. The bacterial diversity in the bare mine tailing was lower than that of the vegetated mine tailing. The former was dominated by sulfur metabolizing bacteria, whereas the latter was by nitrogen fixing bacteria. The bare mine tailing was acidic （pH = 3.78）, whereas the vegetated mine tailing was near neutral （pH ： 7.28）. The contents of organic matter, total nitrogen, and ammonium acetate-extractable potassium in vegetated mine tailings were significantly higher than those in the bare mine railings （P 〈 0.01）, whereas available phosphorus and electrical conductivity were significantly lower than those in the bare mine tailings （P 〈 0.01）. The results demonstrated that 16S rRNA gene sequencing could be successfully used to study the bacterial diversity in mine tailings. The colonization of the mine tailings by reed significantly changed the bacterial community and the chemical properties of tailings. The complex interactions between bacteria and plants deserve further investigation.