Rapid bioassessment protocols are practical technical references for 
    conducting  cost - effective  yet  scientifically  valid  biological 
    monitoring  programmes. They  provide  reports  that can  easily  be 
    translated to  management and  the  public employing environmentally 
    benign procedures. Several biological communities including plankton, 
    periphyton, microphytobenthos, macrozoobenthos, aquatic  macrophytes 
    and  fish have been  considered in  assessments of  stream and river 
    water quality. However experience from north  American, European and 
    Australian  programmes as well as  extensive studies in Kaveri river 
    system in  India have  demonstrated that the most useful  biological 
    assessment  methods for  routine  monitoring of wadeable streams and 
    rivers are those based on benthic macroinvertebrates.

    The  components of the  suggested rapid bioassessment protocol (RBP) 
    module are
       
        a. Physical  characterization and water quality field data 
           collection and habitat assessment,field data collection 
           regarding channel dimensions, channel gradient, channel 
           substrate size and type, habitat  complexity  and cover, 
           riparian vegetation cover and structure,  anthropogenic  
           alterations and  channel – riparian interaction.
        b. Field sampling,laboratory processing and identification
           (Family level/Genus level) of benthic macroinvertebrate 
           assemblages.
        c. Benthic metrices(Richness measures,Composition measures, 
           Tolerance / Intolerance measures, Feeding  measures and 
           Habitat measures) and  Application of a suitable Biotic 
           Index(BMWP score).
        d. Data Integration through Graphical Display and reporting 
           as Ecosummaries as well as scientific Reports.

    The ultimate objective should be to evolve an empirical (statistical) 
    model, Ind Rivas (similar to RIVPACS of U.K. and its derivative, Aus 
    RivAS of Australia) that would predict the aquatic macroinvertebrate 
    fauna that  would be  expected to occur at a site in the  absence of 
    environmental stress.

    The River Barak originating from the Japvo peak(11,000 ft)in Nagaland, 
    flows  through a  tortuous  course of c  532 km in  the  provinces of 
    Manipur and Assam before bifurcating itself into two tributaries,viz., 
    the  Surma and the Kushiyara. In course of its flow, Barak receives a 
    number of  tributaries in the  Assam  region, notably the Jiri, Chiri, 
    Jatinga and Madhura in the North bank; while, the river Sonai, Ghagra, 
    Katakhal and  Dhaleshwari  meet the  River  Barak in its  south  bank. 
    Ichthyological study revealed that fish species of River Barak belong 
    mainly  to the  following  families,  viz.,  Cyprinidae,  Balitoridae, 
    Cobitidae,  Bagridae,  Siluridae,  Schilbeidae,  Sisoridae, Channidae, 
    Chandidae,  Nandidae,  Gobiidae and  Mugilidae. Puntius sp. generally 
    show major abundance(22.3%) followed by  Mystus spp(17.9%) and Chanda 
    spp (17.9%). Indian  major carp  population has since declined (0.25%) 
    mainly  because of  loss of their  breeding grounds. Other fish types 
    which have been exhibiting marked decline include fishes belonging to 
    the genera Salmostoma, Notopterus, Hilsa, Aorichthys,Ompok, Ailia and 
    Bagarius. Study of  physico-chemical and other parameters reveal very 
    poor  assemblage of  aquatic  macrophytes in the  Barak drainage with 
    Eichhornia  crassipes  sometimes seen being drifted by river currents. 
    The  ichthyofauna  composition  in all the  tributaries  show  common 
    elements. Physico-chemical  parameters of water of the Barak drainage 
    revealed water temperature ranging from 12-35 c;turbidity from 23-897 
    NTU, pH 6.7-7.2, dissolved oxygen 4.8-7.1 mg/Lit,free carbon di-oxide 
    2.3-6.4 mg/Lit, and total alkalinity 47.0-75.0 mg/Lit. Ichthyospecies 
    composition  of the  Barak  river  and  its  tributaries  along  with 
    management and  conservation of the  fishes and  their  habitats have 
    been discussed in the paper.

    The  main  objective  for  the  above  observations  was to gauge the 
    present  biological and  ecological  status with respect to the above 
    organisms. Information  accessible since about 1982 to 1999 have been 
    considered to bring out a  comparative status of this wetland habitat 
    in order to look for any observable ecological changes.Some important 
    physico-chemical parameters have been considered.

    From  these  past  studies,  using  the  indices  by  Rawson,  Sawyer, 
    Vollenveider and  Palmer for the algal species and by considering the 
    nutrient  levels of  phosphorus and  nitrogen, this habitat is easily 
    classifiable as a polluted eutrophic lake. It appears that water body 
    could have turned eutrophic even earlier to 1982.

    Some significant observations are made and discussed in the paper.For 
    instance,it is seen that the pH has increased over the years, causing 
    a shift towards algal dominance by Spirulina species from the earlier 
    dominance by  Microcystis  species. Over  the years  dominance by the 
    Myxophyceae as a  group is  clearly  observed among algae. Further in 
    general, it is  seen that the  diversity of  both  phytoplankton  and 
    zooplankton has  decreased. Some  members are clear indicators of the 
    increasing levels of pollution.

    During 1982-84, 21 species of fish and 6 additional stocked varieties 
    were recorded and as of 1999,the diversity was noticeably low at just 
    3 species  including  Tilapia as a  latter  addition, as this was not 
    recorded during the earlier period. Further it is observed that there 
    has been a decrease in the waterfowl and other avian faunal diversity, 
    especially with  respect to the waders. Loss of habitat and polluting 
    influences could be the major reasons.Such aspects would be discussed 
    in this paper.

    Recently, this  habitat has been  taken up for  ecological renovation/
    remediation  measures on a  model  basis. In  light of the  above and 
    having  this  habitat  as  a  possible  background  test  model, some 
    observations  are  made and  suggestions  for  management  of wetland 
    habitats in the future in urban, suburban and  rural scenarios are to 
    be discussed through this paper.

    Removal of  nutrients from waters entering lakes and tanks to prevent 
    eutrophication is an  important  component of  waste-water  treatment. 
    This  can  be  achieved  by  a  turnover  of  floating  and  emergent 
    vegetation. With periodic removal or harvest of biomass from the lake, 
    a continuous removal of nutrients from the water is possible. However, 
    decomposing aquatic and semi-aquatic vegetation present in such lakes 
    could  itself return  nutrients into water  rapidly. Therefore, there 
    could  be  merit  in  substituting  soft  tissued  plants  with woody 
    vegetation (trees). Trees  from  tropical,  intertidal  and  adjacent 
    communities could be viable alternatives in afforesting inundated and 
    foreshore  areas of  tanks and  lakes. They could be  much larger and 
    capable of  creating an aesthetically appealing microclimate of their 
    own, and  being woody, would be less likely to  decompose and  return 
    nutrients to the water. These  species could also grow better in such 
    nutrient-rich and  deoxygenated soils and sediments found in our tank 
    and lake beds. Different  aspects of such a  scenario are  elaborated. 
    Given  that  not  less  than  fifteen  percent  of  the  tanks in the 
    Bangalore  area could be  eutrophic, a good tree  growth in  standing 
    water could  effectively ‘contribute’ to  the ‘green space’ of  urban 
    Bangalore.

    Ground  samples of  Pandavapura town, numbering 20 were  analyzed and 
    have  been  processed  using  the   HYCH  program  developed  in  our 
    laboratory and 16 different thematic maps(directly useful for various 
    consumer demands – TDS, Ec, SAR, CR, Groundwater Hardness,Groundwater 
    Salinity,  Sodium  Hazard,  RSC  and  NO3  and IBE, Groundwater types, 
    Stuffrand’s   water   types   and  subtypes,  gibbs  paleoenvironment, 
    saturation  Index  and  Environmental  characters  for  academic  and 
    research utility) were prepared and are presented here.

    In any aquatic ecosystem, Carbon, Phosphorous and Nitrogen (CPN)have 
    been  regarded as  the  most  important  elements in the  production 
    process  and  eutrophication  of  water. While  information  on  the 
    physico-chemical  characteristics  of  fresh  water  impoundments is 
    available  from time to time,  considerable  paucity of  information 
    exists  regarding the  CPN  turnover and  productivity in such water 
    bodies. This paper provides an insight into the changes in CPN level 
    of water and sediments and their influence on the primary production 
    of the Sankey Tank, Bangalore. This tank (termed as reservoir as per 
    State  Gazetteer) is 460  years old and  harbours a  rich fish fauna. 
    Despite  considerable human  interference especially during festival 
    seasons, the tank is  still  usable for  recreational  purposes. The 
    results  indicate that  though the CPN  levels of the tank water are 
    low, the  sediment  serve as a rich reservoir of this nutrients. The 
    CPN levels in the tank  supports a rich  production of Chlorophyceae 
    members  followed by those of Bascillariophyceae. The annual changes 
    in the CPN levels in the water and sediment of the tank suggest that 
    the tank is still mesotrophic in nature.