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MACROPHTIC DIVERSITY IN CERTAIN WETLANDS OF BARAK VALLEY REGION IN ASSAM

Debashish Kar &
Monjurul Hoque Barbhuiya
    Aquatic  macrophytic  diversity and its  role in  understanding the 
    wetland ecosystem dynamics is of significance tremendously. Species 
    composition of the  Aquatic  macrophytes (AM), their succession and 
    phytosociological status in four  wetlands of the Barak Valley, viz., 
    Barak-Nadi  Salchapra  Anua Beel, Satkarakandi Anua Beel, Ram Nagar 
    Anua Beel and the  Chatla  Haor were studied during the 1998-99. 25 
    different  species of AM were  recorded from the  studied  wetlands, 
    which  included 5 free floating, 6 rooted floating, 3 submerged and 
    11  emergent species of AM. Significantly, six AM species have been 
    found to occur  throughout the year. While  Jussiaea  repens showed 
    flowering  during April, Nymphaea  nouchali bloomed during June-Aug 
    followed by  Nymphoides  cristatum and N. indicum  which  exhibited 
    profuse  flowering  during  Sep - Oct.  Ipomoea  aquatica  depicted 
    significant  growth  of  population  during  July-August.  Hydrilla 
    verticillata ,  Vallisneria  spiralis,  Noechamendra   alternifolia, 
    Eleocharis acutangula, Sagittaria trifolia, Scirpus eriophorum were 
    found to be  dominant during the dry season. The floating varieties, 
    viz., Eichhornia  crassipes, Salvinia  cucullata and Azolla pinnate 
    were  recorded  throughout the year and were found to be associated 
    with  each  other.  Further,  H. verticillata,  V. spiralis  and  T. 
    bispinosa were found to be associated. Phytosocial association have 
    also been  observed among  Nymphaea sp and Nymphodides spp, as well 
    as, among E.acutangula, S.eriophorum and Echinochloa stagnina.

    Species  composition and  succession along with significance of the 
    phytosocial association have been discussed in the paper.



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STATUS OF BENTHIC AND LOTTORAL FAUNA OF A LENTIC WETLAND HABITAT IN THE BANGALORE URBAN REGION WITH ASSOCIATIVE ECOLOGICAL MANAGEMENT STRATEGIES SUGGESTED

B.K. Chakrapani and S. Ravichandra Reddy
    The Benthos and  Littoral fauna of an aquatic habitat  especially in 
    the context of inland  freshwater  wetlands can be more  effectively 
    reflective  of the  operative  environmental  conditions   than  the 
    physico-chemical  indices as is more commonly used. The  benthos and 
    littoral  fauna may  provide  for  use  as  possible  rapid  overall 
    ecological  bioindices  to  gauge  the  ecological  as well  as  the 
    biodiversity status of wetland ecosystems.

    The  littoral  fauna  especially ,  could   also  provide  important 
    information in understanding and possibly gauging the potentialities 
    of  fishery  development  from  the  point of view of  socioeconomic 
    aspects.

    An  assessment  of  these  faunal  aspects  can  definitely  provide 
    important  cues and start-up ideas for  shore  management strategies. 
    Such  strategies  are  a  key  to  the  maintenance   and  effective 
    conservation of  wetlands in a sustainable manner considering a wide 
    range of  aspects  concerning  wetland  ecosystems. In  the  present 
    scenario, sustenance of  biodiversity would be the most important of 
    these aspects and this would indirectly be linked to the enhancement 
    of ecological and socioeconomic considerations.

    In this  light, the benthic and littoral fauna of fresh water lentic 
    habitat(tank in local parlance-also referred to as lake)was assessed 
    over a 15-month period in the early eighties. The population density 
    and the  biomass were  estimated. The Madivala tank which was in the 
    urban  fringe  area till  about the early 1980’s, has presently come 
    much within the urban limits of the rapidly developing and expanding 
    Bangalore city since about the mid 1980’s.

    The  benthic  fauna was seen to be  represented by annelids, insects, 
    crustaceans, mollusca and the  pisces of which the insects dominated. 
    The  littoral  fauna was  seen to be  represented  by the  nematodes, 
    annelids, insects, crustaceans, molluscs  and  the pisces. Of  these, 
    the crustaceans were seen to dominate.

    Some  interesting  ecologically  significant  observations were made. 
    For example,though on the whole a fairly good number of fish species 
    were found in this habitat, it was interesting to find the dominance 
    of considerable numbers of only two of them, being largely supported 
    in the  littoral  region. This was  observed  to  be  more so in the 
    regions associated with the water hyacinth Eichornia crassipes which 
    also supported  profuse numbers of the mosquito larvae.

    On  similar  considerations, a  general idea is also  gathered for a 
    number of habitats with respect to shore ecological features and the 
    biota  supported. The  diversity of  littoral  aquatic vegetation as 
    being a  very  important  component  of  the  wetlands is also to be 
    brought in this paper.

    Further, considering  these  aspects  the  possibilities of evolving 
    habitat  related   ecologically   suitable   management   strategies 
    involving  shore regions of wetlands would also be discussed in this 
    paper.



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AIR QUALITY MONITORING AND MODELING FOR COIMBATORE CITY

P. Meenakshi and R. Elangovan
    The air environment, unlike  water can not be purified at a central 
    location and reused. As a nonrenewable  resource, extreme care must 
    be  exercised  to  maintain  good  air  quality,  inspite of  rapid 
    industrialization and  urbanization. The  Coimbatore  City has cool 
    climate and  locked almost on all sides by hills. Hence  dispersion 
    of air pollutants is limited and the air quality gets  deteriorated. 
    Regular monitoring of air quality is very  important in such a case. 
    Since regular air quality monitoring is time consuming and involves 
    heavy utilization of funds and manpower, this tedious procedure can 
    be eliminated if a suitable model can be developed and used for air 
    quality  prediction. As a  case study, air  quality  monitoring was 
    done at five  selected  survey stations in this city. The major air 
    pollutants  like  SPM, SO2, NOX  were  monitored in  each of  these 
    survey  stations  once  in  a  week . Along  with  these  polluting 
    parameters   meteorological  parameters  such  as  wind  speed  and 
    direction, wind  temperature  and  pressure ,  humidity  were  also 
    monitored. A  statistical  regressive model was  developed relating 
    the  polluting parameters with the meteorological parameters, which 
    can be used in the future for predicting the air pollution.



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THE BIODIVERSITY STATUS OF PLANKTON IN TANKS AS WETLAND HABITATS OF THE BANGALORE REGION, KARNATAKA, INDIA

B.K. Chakrapani
    The  Bangalore  region, in  the past, in  view  of  its  undulating 
    topography and the  historical  developments in terms of its growth 
    as well as the needs of its people has  supported the creation of a 
    large number of tanks - about 389 as per records. These tanks which 
    served to store or  harvest the  rainwater, in the ecological terms, 
    are lentic water impoundments created by building of man-made bunds 
    across  mainly  seasonal  streams/minor  rivers flowing through the 
    valleys in the  region. Initially the  tanks served to cater mainly 
    the  agricultural (irrigation) needs  and  others  like  water  for 
    drinking and other  domestic  utilities. Economic value in terms of 
    fish and other minor  aquatic  procedure resources were also served. 
    Here it is significant to note that from the time of  establishment 
    of  Bangalore in the  early 15th  century by  Magadi Kempegowda and 
    developments during  Hyder Ali’s period during mid 18th century and 
    later  as  an  important  military  town  by the  British from 19th 
    century and later after the independence, it saw a steady growth in 
    the initial  stages. The pace was faster since about the 1940’s and 
    very rapid since around the mid 1970’s.

    During the above changes,Bangalore’s urban area has seen tremendous 
    ecological changes in terms of its water resources of streams/minor 
    rivers and  therefore the  tanks fed by these sources. The streams/
    minor rivers steadily  changed over to  make way as the smaller and 
    bigger  storm  water  drains  which  drained the city’s waste water 
    into the tanks. Thus the scenario has changed the status of many of 
    the tanks ecologically over time especially in the urban areas.

    The ecological importance of tanks(wetlands)being wide  ranging and 
    multifarious is both  scientifically as well as  socio-economically 
    well  established. In  fresh water lentic ecosystem like these, the 
    plankton  community both as  producers (phytoplankton) and  primary 
    consumers (zooplankton), trigger off the initial biosynthetic steps. 
    They also form  important links  between the basal  abiotic and non-
    living (organic) matter and the  living matter. Many foodchains are 
    thus  triggered, eventually leading to the support of larger groups 
    like the molluscs, insects, fish and in turn, the waterfowl.

    India being  a  signatory since  1982 to the ‘Ramsar  Convention on 
    Wetlands of  1971’, is  bound to  protect, conserve and  improve at 
    least its important wetland resources.

    In light of the above, plankton  surveys were conducted during 1989 
    and 1995 of such  wetland habitats (tanks) mainly during January to 
    coincide with the  Midwinter Annual Asian waterfowl censuses in the 
    Indian region.

    Nearly eightyeight wetlands were surveyed during the two years. The 
    result of these  survey are  provided in terms of the phytoplankton 
    and  zooplankton  biodiversities  from  these  habitats   and   the 
    significant  ecological  inferences which could be drawn would also
    be discussed in this paper.



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POPULATION DYNAMICS OF AQUATIC INSECTS IN FRESHWATER
BODIES OF GULBARGA

K.Vijay Kumar, S.Gayatri
and K.Shailaja
    Population  dynamics of  aquatic insects was studied in  freshwater 
    bodies of  Gulbarga. Eutrophication, high  turbidity, low dissolved 
    oxygen, high alkalinity, free carbondioxide and total hardness were 
    the abiotic factors preventing the diversification and abundance of 
    aquatic  entomofauna in the Jagath tank. A few aquatic insects have 
    been regarded as biological indicators of pollution.
    
    
    







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BIOCHEMICAL ASPECTS OF WATER POLUTION IN TWO LAKES OF MYSORE CITY

Hosmani S.P. and L.Vasanth Kumar
    A  detailed  study  of  the  physico - chemical   and  bio-chemical 
    parameters in  Kukkarahalli lake and Dalvoi lake indicates that the 
    gross  percentage of  chemical  parameters in  Kukkarahalli lake is 
    27.90% and the percent of total plankton is low (43%). The activity 
    of  chemicals lead to the  liberation of  extra  cellular  products, 
    thereby  increasing their quantity (53.19%). The death and decay of 
    plankton may  add  to the  activity  of  bacteria in this lake, the 
    quantity of  bacterial  colonies also  increases(57.5%). In  Dalvoi 
    lake the  percentage of chemical is very high (72.09%) and plankton 
    is also  relatively high (56.80%). The  percentage of  bio-chemical 
    parameters is correspondingly low (46.80%).

    Both  lakes  seem to be  highly  productive, one  on the  basis  of 
    bio-chemical products (Kukkarahalli Lake) and other on the basis of 
    plankton productivity(Dalvoi Lake). Death and decay of algal blooms 
    in these waters add to the bio-chemical concentration. These waters 
    have  comparatively high  electrolytes, the dissolved oxygen is low 
    while phosphate and nitrogen content are relatively high and show a 
    quantitative abundance of plankton blooms and are highly eutrophic.

    Exploitation  of  polluted  waters   rich  in   algal  biomass  for 
    biotechnological  products  can be  established.  Phycobiliproteins 
    from algae can be used as sensitive fluorescent dyes,immunochemical 
    reagents and  can be used as  efficient  flurochromes  in  multiple 
    colour analysis.



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TEMPORARY PONDS - A NEGLECTED ECOSYSTEM

M.N. Madhyastha,
K.C.Shashi Kumar and P.D.Rekha
    Temporary  ponds and  puddles are by and large neglected ecosystems 
    and generally  undervalued till recently. But their contribution to 
    the ecosystem function is significant. They support wide variety of 
    organisms  including varieties of higher plants requiring different 
    stages  of  water  level,  supporting  some  rare  plants,  various 
    amphibians and their  tadpoles and many microorganisms. In addition 
    provide nesting and perching habitats for birds to rear their young 
    and provide  resting areas. Many migratory birds also stop and rest 
    in these areas. Despite their  temporary nature, they support these 
    biota both during wet and dry seasons. They contribute immensely to 
    the village population, meeting its immediate water demands.

    These  small  ponds are  utilized for a variety of human activities 
    like drinking and small scale agricultural water supply, recreation,
    fishing as well as for  dumping  agricultural and  domestic  wastes. 
    Inspite of  their  importance towards  supporting diversity of life, 
    they are  amongst the  vulnerable and easily damaged of the aquatic 
    ecosystems. The  anthropogenic activities filling the shallow water 
    bodies exert  a stress on  these systems. These  fragile ecosystems 
    are being  destroyed completely because of inappropriate management 
    practices. The temple tanks are not exceptions to this. The organic 
    loading  results in the  complete coverage of these waters by algae 
    and floating  macrophytes like Salvinia, pistia, and Eichhornia spp. 
    Further it  leads  to  the  eutrophication  process  increasing the 
    biochemical  oxygen  demand  and  decreases  the  oxygen level when 
    decomposed by  microorganisms, which in turn  exhibits shift in the 
    natural,  healthy  flora and fauna leading to ecological succession. 
    Hence  there is an  urgent need to examine their status and role in 
    the biodiversity conservation and action as well. Proper management 
    plans  involving  the  local  people’s  participation  will help to 
    restore the health of these wetland ecosystems.