a borítólapra  Súgó epa Copyright 
Applied Ecology and Environmental ResearchVol. 2. No. 2. (2004.)


  • Borítóen [519.72 kB - PDF]EPA-02583-00003-0010
  • P. Mehrotra ,
    G. Kharakwl ,
    Y. P. S. Pangety :

    Abstract: Natural selection generally favors plants whose forms and physiology tends to maximize their net rate of growth, because plant uses resource to reproduce and compete for additional space. Above ground characteristics of a plant often greatly affect its competitive abilities and population dynamics rather than below ground because drymass of a plant depends on leaf strategy, where as root in the top soil is responsible for exploitation, competition through depletion of a common pool of resources so fine roots are also important. The use of root/shoot ratios to describe allocation of dry weight to structures for capturing soil resources and light is limited due to other functions of the root and shoot such as storage and support. Dry matter allocation, specific leaf area, root length and different ratios were determined for 17 herb species by extraction of soil cores from an intact forest. Interspecific values of RLA were considered. It has been hypothesized that the co-variation among species in leaf trait and other morphological adaptations particularly leaf and growth rate reflects a set of mutually supporting traits that interact to determine plant identity in similar climatic conditions.

    Keywords: Herbs, above ground characteristics, dry matter allocation, SLA, RLA, root length, root: shoot ratio

  • G. Kharkwal ,
    P. Mehrotra ,
    Y. S. Rawat ,
    Y. P. S. Pangety :

    Abstract: Species richness of pine forest along with elevation varying from 1800 m (site A) to 1500 m (site B) at central Himalaya was compared to judge the ecological significance. A total of 56 species comprising 51 genera and 28 families were recorded. Alpha-diversity and equitability or evenness was significantly higher at site A as compared to the site B. The number of families, genera and species observed in site A were also higher than site B. Very few herb species were found common in both the forest sites and indicated lower values of similarity index. Asteraceae and Lamiaceae were the most dominant family at both the sites. The percentage contribution of annuals and perennials were 48.1% and 51.9%, respectively. Species diversity at site A was more than at site B. This may be due to more gentle slope at site A than at site B. The ability of retention of more water in the soil provides favourable condition for plant growth. The study revealed that the forest site A is more diverse, old and stable in comparison to site B.

    Keywords: herb species, family, pine forest, species diversity, species-area curve

  • J. Mohan ,
    R. Prakash ,
    J. R. Behari :

    Abstract: A Novel Ni(II) mixed ligand complex modified graphite electrode is developed for detection and oxidation of the phenolic compounds based on simple cyclic voltammetric technique. The Ni(II) mixed ligand complex with thiocyanate and macro cyclic ligand 1, 4, 8, 11 tetraaza cyclotetradecane (cyclam) was synthesised and used for catalytic oxidation of phenolic compounds viz. phenol, nitro-phenol and chloro-phenol etc. The Ni(II)-cyclam-thiocyanate mixed ligand complex was synthesised in typical molar ratio of 1:2:5:: Ni(II):cyclam:thiocyanate and crystallized followed by characterization and catalytic applications. The electrochemical study of the complex mediated graphite electrode revealed its fast electron-transfer property, as formation of higher oxidation state of central Ni(II) metal ion as Ni(III) on applying a positive potential, which catalyses the oxidation of the target species. The Ni(II) complex modified graphite paste electrode enhanced the oxidation current of phenolic compounds many times relatively at lower oxidation potential in comparison to simple graphite paste electrode. It is also found to be sensitive for the detection of various phenolic compounds in the range of 20 mg/L to 0.5mg/L in aqueous solution. The Ni(II)-complex stability at higher potential and ambient condition proved its potential for sensing and detoxification of phenolic compounds released in the ecosystem from polluting industries.

    Keywords: Cyclic voltammetry, chemically modified electrode, mixed ligand complex, phenol oxidation, detoxification

  • S. P. Paghuvanshi ,
    R. Singh ,
    C. P. Kaushik :
    Kinetics study of methylene blue dye bioadsorption on baggase35-43en [585.04 kB - PDF]EPA-02583-00003-0050

    Abstract: The adsorption potential of agricultural (sugarcane) by-product, the baggase was investigated in batch experiments with two different forms i.e., raw and chemically activated forms, for the removal of Methylene Blue dye, with different parameters like dye concentration, contact time, temperature and adsorbent dose. The removal is better and more effective with chemically activated baggase in comparison to the raw baggase. An average percent removal difference between the two adsorbents of around 18% was achieved under the different conditions in the experiment. The data fit well in the Freundlich isotherm.

    Keywords: Adsorbent, Adsorption, Methylene Blue dye, Raw Baggase, Chemically Activated Baggase

  • H. M. Rifaat ,
    A. H. Awad ,
    H. M. Gebreel :

    Abstract: Many different microbes, including actinobacteria thrive in the conditions offered by moisture nutrient materials, which are needed for microbial growth. The actinobacteria isolated and identified from the atmosphere surrounding chamomile plants cultivated at El-Fayoum Governorate, Egypt reached a maximum concentration during harvesting period of chamomile plants. The main components of the airborne bacteria in the atmosphere of the studied area were Streptomyces, Micrococcus , Rhodococcus, Arthrobacter, Microbacterium, Cellulomonas and Nocardia. These bacteria have an important role in the spreading of allergic diseases among the population during the harvesting of the chamomile plants and indicate a potential risk of occupational respiratory disease.

    Keywords: characterisation, actinobacteria, atmosphere, chamomile plant

  • A. Ciolac ,
    N. Patriche :

    Abstract: The main purpose of this paper is to actualize last data on Danube shad (Alosa pontica Eichwald, 1838) migration process in Danube River. This species was widely studied last time in Danube River, but there are still some biological and ecological aspects to be revealed. Study of periodical changes in the total amount of capture and spawners structure could bring more and relevant information on presumed cyclic decrease and increase of stocks and also about the main causes of their interesting population dynamics. We try to examine some other aspects related to the spawning biology as well as to the biometry of different age-classes and also to link these issues to the last changes in environment conditions.

    Keywords: Danube shad, Migration, Captures, Stocks structure

  • Abstract: OptiNet is a PC program for optimal network selection. The aim of this study is to test the program by simulation experiments and to investigate the robustness of the optimal selection. One of the most important results is that the area should not be represented by an equidistant grid to calculate the maximum Kriging prediction variance, it is sufficient to investigate the boundary points only. Effects of the parameters of the covariance function, the number of selected points and of a possible factor were also investigated. All simulations are based on the Gauss-Krüger coordinates with 1 m raster in the area of Brandenburg.

    Keywords: spatial statistics, optimal design, simulation, kriging, covariance function

  • D. Rédei ,
    B. Harmat ,
    L. Hufnagel :

    Abstract: As a third part of a series of papers on the ground-living true bugs of Hungary, the species belonging to the lace bug genus Acalypta Westwood, 1840 (Insecta: Heteroptera: Tingidae) were studied. Extensive materials collected with Berlese funnels during about 20 years all over Hungary were identified. Based on these sporadic data of many years, faunistic notes are given on some Hungarian species. The seasonal occurrence of the species are discussed. The numbers of specimens of different Acalypta species collected in diverse plant communities are compared with multivariate methods. Materials collected with pitfall traps between 1979–1982 at Bugac, Kiskunság National Park were also processed. In this area, only A. marginata and A. gracilis occurred, both in great number. The temporal changes of the populations are discussed. Significant differences could be observed between the microhabitat distribution of the two species: both species occurred in very low number in traps placed out in patches colonized by dune-slack purple moorgrass meadow; Acalypta gracilis preferred distinctly the Pannonic dune open grassland patches; A. marginata occurred in almost equal number in Pannonic dune open grassland and in Pannonic sand puszta patches.

    Keywords: Heteroptera, Tingidae, Acalypta, phenology, habitat preference, microhabitats