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ENVIRONMENT OF KERALA A STATUS PROFILEDr.Thrivikramji.K.P. (Retd)thrivikramji@yahoo.comDept. Of Geology, University of Kerala,Kariavattom 695 581

ABSTRACT

State of Kerala, based on its physiography, is divided into three regions viz., highland (elv.=>75.0 m), midland (elv.=8.0 -75.0 m) and coastal land (elv.=

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hydrosphere or fluid earth and lithosphere or solid earth or the Physical system. In otherwords, the respective earth-spheres and their makeup, processes, products and resourcesexercise a great deal of influence on the human civilization, i.e., life style or quality of lifehumans. Among the members of the biosphere, demands by human population for resourcesare not only largest and rising but often devastating in nature, in so far as the balancebetween resources and organisms are concerned. It is this latter trend, a rising demandspiral that is the foundation for most of the environmental issues.

PHYSICAL SYSTEMPhysiographyLocated at the southwestern corner (between N.Lat.8

o18 12

o.48 and E.Long.74

o

52 and 77o

22) in the map of peninsular India, Kerala s western boundary or Laccadive seashoreline, is seemingly made of a complex of arcs of varying radii, whereas its eastern border(with the Tamil Nadu) is an irregularly serrated one, chiefly due to influenceof divides of westflowing streams. But for the flabby or wide mid-section in south Kerala say @80 km alonglatitude of Ernakulam (Chathopadhyaya, 2004), southern and northern boundaries of the stateare typically short in length, giving an overall ribbon like, or narrow-rectangular outline, with ashore line length of 570 km.

Before going any further, a check on the physiographic make up of Kerala is in order. Table.1is a summary of the physiographic divisions of Kerala (which are only indirect manifestations

of lithosphere) equated to zones identified for management purposes. Coastal land, mid-landand high land (with its intrinsic sub-units, viz., low-highland and high-highland) are the chiefphysiographic divisions limited by elevations above m.s.l. Recently Chathopadhaya (2004)reported that nearly 62% of the land area falls below an elevation of 100 m.

Table 1 Pysiographic units, limiting elevations, extent anddivisions,Kerala (modified by Thrivikramji, 1992)

UNIT ELEVATION,m

AREA,km2

Division

Coastal land 600.0 7,420.0

Highland zone

Total area, km2 38863.0Population, crores(Census, 2001)

3.18

ClimateKerala, according to Koppen s scheme classification, has a typical tropical monsoon climatewith clear spells of excessively wet monsoon season (NE and SW monsoons) separated byvery humid and dry summer season. NE monsoon is weak in northern Kerala. It is nowbelieved that the SW and NE monsoons are part of one and the same system, whose windsreverse in their direction to generate both monsoons. Average annual rain fall hovers around3000 mm and as a consequence, Kerala earned disrepute as one of the water surplusstates of the union. On the contrary, water needs of the state are on an ascending spiral dueto a multiplicity of reasons (like poor water conservation, and wasteful practices, populationgrowth, shift in landuse, improved quality of life, rise in commercial and industrial consumption

etc.). GEOLOGICAL SETTING

Natural resource potential of any terrain is a dictate of its geological makeup. Kerala is noexception. The rock formations are known to host variety of ore and industrial minerals as wellas fossil fuel deposits like coal, oil and gas. With this back drop, let us checkout the geologicalmake up of the terrain of Kerala.

Lithological formationsSoman (2002) summarized the geological framework of Kerala. In short, chief lithologies orrock formations of Kerala are essentially granulites and associated gneisses of Precambrian

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age. Small and large granite intrusives and pegmatites of Precambrian to early Paleozoic erahave also been mapped. Intrusive dykes of Mesozoic to Cenozoic age are known to occur inthis poly-metamorphic terrain (Table 2). Lithologies of Precambrian that underlie the high-highland, low-highland and part of midland are garnet-sillimanite gneisses, charnockites,pyroxene granulites, hypersthene-diopside gneisses, granites, garnetiferous leptynite, andgarnet-biotite gneiss. Northern Kerala does show extensions of rocks of Dharwar group.

Based on a examination of LANDSAT imageries of Kerala, Varadarajan and Balakrishnan(1980) reported several sets of major and minor lineaments traversing the terrain andproposed that some of the lineaments could have been deep seated fractures. NE-SW andENE-WSW trending lineaments are considered as youngest (Nair, 1990). NW-SE, NNW-SSE,and N-S lineaments perhaps played critical controls on the courses of the valleys, now theloci of major river channels. Lineaments along with joints and foliation, fracture zones anddepth of weathering exercise huge control over nature, size and extent of ground waterreservoirs or aquifer qualities of this terrain.

Table 2.Stratigraphic succession, Kerala (modified after Najeeb, 1999)

GeologicalAge

Formation Lithology

Quaternary Vembanad FormationSands , clays, molluscan shell beds,Riverine alluviam and flood-plain sediments

Warkalli formation Sandstone and clay with lignite seams

Quilon formationLimestones, marls, clays/calcareous claysWith marine fossils

Tertiary

Vaikom formationSandstones with pebbles and gravel beds,Clay and lignite and carbonaceous clay

Mesozoic toArchaean

Intrusives: veins of quartz, pegmatites, granites, granophyres, doleriteand gabbro.Garnet-sillimanite gneiss, hornblende-biotite gneiss, garnet-biotiteGneiss, quartzo-feldspathic gneiss, charnockite gneiss etc.

Paleozoic and Mesozoic sedimentary rocks are typically absent and are unreported from thestate. Sedimentary rocks reported from Kerala are of Neogene age and are confined to thecoastal land of Kerala. Framework of High coastal land is mostly the Laterite capping of theWarkalli sedimentaries or occasionally Precambrian crystalline rocks. Coastal sedimentary

basin fill, the only record of sedimentation in the geologic history of the state, is composed ofclastic rocks like clays and sandstones and marine carbonates and impure clastics.Geologists believe that the coastal sedimentary basin is only a landward extension of a largeroffshore basin with a potential for fossil fuels. The youngest of the geological formations,i.e.,Vembanad formation, is composed of sands, clays, molluscan shell beds, riverine andbeach alluviam. Ground water aquifers, in free and sub-artesian conditions, have beenreported from the coastal sedimentary fill and water is actively pumped for consumption.However, appreciable fluoride level has also been reported from one pumping well inAlappuzha and some others in Palakad dist.

Laterite, a term introduced by the French traveler Francis Buchchanan, is a ubiquitous rock oftropical countries of the world, like Australia, India, South Africa and Brazil. Laterite is acommon cap rock over the sedimentary fill as well as the granulite terrain. Unique tropicalmonsoon climate, with alternating wet and dry seasons and widely fluctuating water table,

enables formation of thick Laterite cover. Abundant pore spaces and weak zones in theparent rocks (e.g.,charnockite, khondalite, gneiss or sandstone), enable very efficientdrainage by groundwater and consequent removal of cations like sodium, potassium, calcium,and magnesiumin the constituent silicate minerals, transforming them to kaolin. But, commonquartz is inert to the chemical weathering process and goes unaffected. Unlike the ions in theforegoing list, nearly immobile iron accumulates in the residue or Laterite cap as limoniteand/or goethite, as it defies transport by solution. By contrast, in the profiles, particles of clayphysically move downward under the influence of gravity and descending waters toaccumulate as a layer of kaolin rich lithomarge. Carbonate, sulphate, phosphate etc. are thechief anions reported from surface water.

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Soils

Soils are typical products of weathering of basement rocks of any terrain and their nature isprimarily controlled by factors such as climate, parent rock and altitude or elevation of theregion. Tropical monsoon climate and associated very high rain fall (~3000 mm /annum) arelargely responsible for the thick Laterite cap that covers most of the midland terrain of Kerala,pockets in the coastal land and some areas of low-highland juxtaposed to midland. The chiefsoil groups have originated directly or indirectly from Laterite, Generally lateritic soils are

acidic in nature.

NATURAL RESOURCESAgainst the tall claims, no land area of the globe is endowed with every natural resource (fore.g., raw materials like ores, minerals, oil, gas and drinking water, or climate conducive togrow a large variety of food stuff). With developments in science and technology, shippingand transport or transfer of raw materials or finished products (in solid, liquid or gaseousstate) from place of origin to one of need and consumption, has become essentially a non-issue. But, other side of this coin is wrought with issues relating to handling, storage and safeand scientific disposal of wastes, which are part and parcel of manufacturing andconsumption. Kerala is no exception. Huge quantities of raw materials, industrial products andfood stuff are brought in on a 24x 7 basis to supplement or meet local demand.

Now, a brief sketch of resources of Kerala will be in order. Generally speaking, in respect of

both agricultural commodities and finished products, Kerala is branded as one the consumerstates of union of India. A glance of Table 3, a resource fact-sheet (qualitative) for Kerala,reveals that important other raw materials like coal, oil and gas or large deposits of ores ofimportant metals like iron, copper, zinc or lead are not native to this region.

Table 3 Resource-Fact-sheet, Kerala

A question that might occur immediately in our minds is about the supply and demand pictureof these, or can we can sell off the resources as value added black sand and china clay andplantation produces like rubber, tea, coffee, cardamom and pepper?. Huge quantities of fishare also exported. But steel, cement, fine and finished stones, red-brick and of late evenconstruction sand are steadily brought in from out side of state along with timber etc.

PopulationDuring the past half a century, every census of India reported a steady growth of population ofthe state. Summary of population distribution is given in Table 4. For example, size of side ofsupport square (i.e., per capita entitlement of land area expressed as its square root and in mor km) of a person in Kerala is only 34.90 m. and has been steadily shrinking. In respect ofsome countries in Europe it isseveral km. long and a few tens of km in the USA.

Table 4 Demographic profile, Kerala

And shrinking or small size of support square indirectly points at the pressure on land andother natural resource of a region. Further, in Kerala, quantum and reach of distribution ofincome as well as per capita income and finally the size of disposable income of families arein an upward spiral. Moreover, this state of economy has spiraled growth in the construction

NON-LIVING RESOURCESMINERALS/ROCK PRODUCTS

LIVING RESOURCESFARMS/PLANTATIONS

Black sand & glass sand RubberChina clay Tea, Coffee, pepper & Cardamom

Gold Sea FishBuilding stones, Red-bricks& construction sand

Food stuff (rice, vegetables& banana)Forests, 10815 km2

Population, 3.18 croresDensity, km2 819 personsUrban 82.67 lakhs

Rural 235.71 lakhs

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sector fuelling consumption of large volumes of raw materials (like cement, steel, bricks,timber, etc.) some of which are sourced from within and some from without and caused avariety of human actions in the environment.

Further, the not so new paradigm of PPP (where the three P s are Population, Poverty andPollution), squarely points at the linkages among the P s themselves and how it finally linksitself to the environment. Only in countries with low levels of economic development,

population fuels poverty and pollution. So when we consider the environmental question, it isno wonder that population factor looms large.

STATUS OF ENVIRONMENT

With a background of geological set up and resources vis--vis population factor, let usexamine the current status of the environment and its future possible course/s. Every programdesigned for economic development and founded on scientific principles and procedures,concerns about the environment is part of the public psyche; where as in countries like Indiathe concern should originate in the mind of the administration and the political system runningthe administration. Table 5 is summary of the status of the environment, in terms of resourcecapabilities and environmental issues. In what follows, environmental issues, intrinsicallyconnected to non-living resources and squarely facing us, will be brought to focus.

Table 5 Status of Environment: Regions, Resources and IssuesRegion Resource Issue

Coastalzone

Mineral sand, KayalsAnd Ground water

Coastal erosion; Mining; Pollution of coastalwaters and inland water bodies;Drinking waterand Sanitation; Shifting landuse

MidlandZone

Water, Land, Soil,River Sand andRock

Shifting Landuse; Quarrying rock and soil;Borrowing of River sand; Water and Sanitation;Pollution

HighlandZone

Prestine NaturalLandscape, Rock-scapes, Prestineforests, Rivers

Shifting Landuse; Pollution of soil and water;Deforestation; Soil erosion; Dams

Coastal ZoneThe coastal zone (area =3610 km2 and ele.=

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seabed sand beach-ward and to be trapped in the back shore of this tract to thicknessesvarying between 3.0 to 4.0 m an act very much akin to that of SW monsoon wave regime.

Coastal erosionCoastal erosion, a constant threat to peaceful life, properties and fishing gear and crafts ofsettlers in the coastal land zone, is a seasonal phenomenon caused by process taking placein the Central India Ocean during the SW monsoon season. The SW monsoon is a boon as

well as bane to the coastal people at the same time. Firstly, Chakara the bountiful fishingground is triggered by monsoon wave activity. Large volume black mineral sand is alsotransported by the same waves and is deposited in the beaches of Kollam and Alappuzhadistricts, which is subsequently gathered and processed by industry. The bane side of theseason is the erosion of beaches along with all the standing property and structures, leavingthe people at the mercy of the government for their daily bread and butter.

Surface water PollutionSurface water accumulating in kayals and man made ponds, is intensely polluted by fertilizerand other nutrient residues, gathered by water from intensely cultivated and tended farms inthe upland. Such nutrient rich waters support luxuriant growth of aquatic weeds, like salvenia,water hayacinth and phytoplankton and when the latter perish large quantities of dissolvedoxygen are used up for the breakdown the tissues or a rise in BOD. Due to this process ofdeath and decay, oxygen levels steadily decline and such water bodies are said to have

reached a state of eutrophication. Surely, these waters easily tend to pollute the subsurfacewaters too, which in turn affect many drinking water supply projects. Pollution of aquifers,break down of distribution system due to lack of maintenance and wastage of water are someof the many ills of the scheme.

Green House gasesSea level rise due to green house effect is a phenomenon caused by increasingaccumulations (chiefly) of CO2, consequent trapping of solar radiation in earth s atmosphereresulting tropospheric heating and release of huge vol.umes of water presently trapped in thepolar ice sheets. This water mass entering the world oceans will consequently raise the sealevel threatening the millions of people settled in the coastal cities and towns across theworld. Higher sea levels will also mean frequent and devastating storm surges and waveerosion. Kerala coast already exposed to beach erosion will have to face the devastatingconsequences of storm surges and increased wave erosion (Thrivikramji, 1992)

PossibleSolutionsOnly intelligent solution available now to save the population in the coastal tract is strictimplementation of Coastal Regulation Zone Act. This will save the people of all the hazards ofcoastal erosion, black sand mining and sea-level rise due to green house effect. Further, ifmining displaces natives, legitimately they must demand compensation not only in the form ofjobs for a member or head of the family or a pension of some sort for head of the family if un-employable by the mining industry and a decent house or apartment for the family, with in adecade of displacement. The only solution for drinking water scarcity is to be found indesalination of sea water by processes like reverse osmosis.

Midland zoneThis tract of Kerala, in the elevation range of 8.0 and 75.0 m, covers a land area of 13476.0km2 is relatively thickly populated as well as intensively cultivated. Most of the area, in thelower elevations, has a relatively thick cover of Laterite, whereas the sectors in higheraltitudes expose sheet rock, isolated rocky hills or ridges. Intervening valleys have resultedfrom active dissection of land by lower order tributaries which are generally of ephemeralnature.

Landuse changesGeneral public is yet to understand the hidden consequences of shifts in land use. In the past,marsh like valley floors of many lower order streams were fashioned into fields suitable forwet-paddy cultivation by terracing and building small dikes of mud to retain water and fromescaping to adjoining patches below. Now, very same fields are remodeled for plantaincultivation. This switch in land use from paddy to plantain, severely affected the ground water

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regime in such tracts. Paddy, essentially one needing standing pool of water, indirectlyensured a longer duration of water recharge to the aquifer/s. Unlike rice paddy, as plantaincrop needs only good soil moisture, planted fields are force-drained by sinking narrow anddeep (as much as one meter) ditches facilitating dewatering of the fields and consequentreduction in the effective duration of recharge. As a result, lower order streams quickly dry up,even indirectly affecting drinking water sources and hence supply.

Yet another feature to enter the environmental hot-list is ponds. All ponds, irrespective oftheir site, size and extent are severely threatened by reclamation, eutrophication orsedimentation, all leading to final elimination. Only ponds attached to places of worship stayout of any risk. Commissioning of dams and distribution network of canals made the pondsredundant any way.

Soil ErosionCultivation of seasonal and annual crops in the upland tract, tended to accelerate the soil lossand hence loss of precious top soil and nutrients. But, with the rising popularity of cash cropslike rubber, the soil loss declined as rubber planted patches were not subjected tilling andinter-cropping for at least 2-3 decades - saving the land from the soil loss phenomenon.

Extraction of rock and sandNew trend in landuse shift from agricultural to residentialor commercial types quickly catching

up all over Kerala, puts a great pressure on land, firstly to source patches of buildable sitesfollowed by basic construction materials like rubble, gravel, sand and brick. Rivers of Keralaare bearing the brunt of construction boom, in that a good deal of river channel sand hasalready disappeared and the rivers are in the brink of ecological demise (Thrivikramji, 1986) .Even paleo-channels or paddy fields have been targeted for removal of sand by innovativetechniques like pumping of subsurface sand.

Changing Hydrogeological domainsDeepening of channels in the river basins due to unprecedented levels of sand borrowing,directly affected the hydro-geological domain/s by deepening of the water table, which forcedmany water wells to dry up un-seasonally resulting in drinking water scarcity. The base- flowor the flow supported by aquifers, i.e., water soaked subsurface layers, in many riverchannels gradually changed to a thing of the past. The aquatic species diversity also steadilydeclined in such river systems as a result of loss of spawning ground either physically ortexturally.

Valley head pond, mid-valley pond or toe-valley pond based irrigation was a main stay offarming people in the recent past. As result of alternatives for ponds, like dam and canalirrigation, gradually shifted ponds to oblivion and neglect. For want of maintenance, a largenumber of large and small ponds went through the process of eutrophication, siltation andfinally filling with dirt and reclamation clandestinely by individuals or publicly by localgovernments. A large number of valley-head-ponds have been going through this transition.Water supply to the house holds either from public water supply or private wells did negativelyimpact the homestead ponds. Thus, yet another facility for recharge of aquifers too, vanished.

Chemical overloading of waterYet another threat to surface water originates, from wetland farms like rice paddy, vegetableand plantain gardens and dry-land farms and plantations, in the form of fertilizer and /or pesticide residues. Eutrophication and gradual death of water bodies are the simplestoutcomes from chemical overloading. Many ponds, as a result slide into their death trap bytransforming themselves into a marsh.

SolutionsAll modifications of landscape, either due to mining or extraction of rocks and minerals or dueto shift in landuse, are fuelled by human needs and compulsions. Therefore, legislations,social or environmental policing does little to secure the situation. A government citizenparticipatory approach might work in diluting the harms so far inflicted on differentcomponents of environment. Educating the societal leaders and the public on the do s anddon t s and what s and how s must help lessen the damages further.

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Fertilizer-residue-forced eutrophication can be stopped or rate slowed down by maintaining aminimum drainage through the system and reduction of residue at the source itself. This callsfor proper and timely maintenance, instead of neglect, in the form of working inflow and outflow chutes and rainwater diversions structures to the pond. By installing water conservationmeasures in the farms, quantum of residue escaping to the surface water system can easilybe substantially reduced.

Alternative materials to river sand like crusher sand and even sea need to be promoted. Thatin countries like ours, government, the role model and first citizen to the public, should committo use of manmade sands in government sponsored constructions.

Highland zone

Culturally, in India until dawn of rail and road transport, the Western G hats was a formidablenatural physical barrier isolating and protecting the natives of Kerala from the rest of thecountry, especially during times of peace. This physiographic unit, with elevations upward of75.0 m, and reaching an average elevation of 2000 m, has Anamudi peaking at 2690 m.Thrivikramji (1993) subdivided this unit into low highland and high highland based on theupper limit of relatively large settlements.

The British cleared several thousand km2 of forest land to create plantations of cardamom,

tea, coffee and teak, which attracted and offered employment to hundreds of families fo mplains inaugurating the first wave of settlement. This process of creating plantations in theforested area continues even to day, though at a slower pace. The need to generatehydroelectric power led to the building of dams to create reservoirs and generating stations.Obviously, construction of arterial roads that followed opened up a new business model oftrade based on produce from forest and plantations.

The second wave of conversion of forestland, soon after independence of India, was muchlarger in scale, and tended to damage the forest ecosystem, reduce the land area under virginforest and perhaps triggered loss of a great deal of fertile top soil. Due to unscientific landmanagement and landuse practices, occasional catastrophic landslides heavily taxing thesettlers became common place, especially during the wet monsoons. As a consequence ofthe encroachment and settling, the magic rule of one- third-forest cover became a distantdream for Kerala and currently it stands at 10815 km2.

PossibleSolutionsProblems of keeping the health of forest and a healthy size are very difficult issues facing theadministration. Legislations are already in place at the national and state levels. As this is anissue at immediate interface between a section of the citizens and administration, rules andpolicing alone will not guarantee the desired results. Only by taking people into confidenceand with their co-operation tangible results can materialize. In fact, a systematic education,about the need for keeping healthy forests, must be offered through formal and non-formaleducation and show-and-tell sessions to the public and especially younger citizens orstudents. Ecotourism is a right step in this direction.

PALEO-ENVIRONMENT

Paleo-environment is a topic of interest to the archaeologists. The principal study materials forreconstructing the Paleo-envronment are minerals in rock, sediment and fossils that theyhost. Fossil is any preserved evidence in the rock on past life. Fossils are of different typeslike body fossils, casts and moulds, impressions like foot prints or tracks. By convention,climate of any location is a function of temperature and precipitation. Then, temperature ofthe past is determined generally based on the presence of certain temperature sensitiveminerals and stable isotope data, Signatures of precipitation or indirectly moisture can besought again from certain minerals and rocks. Fossils when present do provide a secondcheck on the reconstructed temperature and moisture data. Other tools like Carbon 14 dating,amino acid dating etc., come in handy for putting a date or assessing the antiquity of thematerial recovered or site in question. Rock structure and sequence also help a good deal tofurther refine available information on the paleo-environment. Palynology or study of pollen

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gains present in the sediment occasionally comes to the rescue of the investigator. Onlyreducing conditions in the sedimentary environment help preservation of pollen grains. Redcolour of sediment and soil like that of Laterite and red-loam is indicative of oxidizingconditions where pollen grains get destroyed quickly.

SUMMARY

The points discussed in the foregoing sections are summarized below.1. Kerala, occurring along the SW edge of peninsular India, covers an area of 38863

km2 and has a relatively long (length=,570 km.) shoreline. Based on variations inland elevation, three roughly shore parallel subdivisions viz., highland (>75.0 m)midland (8.0-75.0 m) and coastal land (

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7. River channels of Kerala have been loosing one of its chief components, viz., channelbed sand to the construction sector, forcing many rivers to an ecologically dead state.Consequently, hydrogeological regimen of the river valley has undergone changes.Alternative materials like crusher sand or seabed sand are possible subsittes.

ACKNOWLEDGEMENTS

While serving in the University of Kerala, the MOE&F, Govt. of India offered financialassistance to carry out studies relating to the environment of Kerala in the various domainslike river basins, beaches and Teris. The thoughts appearing in the foregoing are an outcomefrom intense and intimate experiences I earned by being in the river channels, beaches, terisand foot hills of Ghats. Finally, I sincerely thank Dr. P. Rajendran, (University of Kerala) andDr. S. Sivadasan (Sri Sankaracharya University of Sanskrit) for this opportunity to read apaper in the Seminar.

REFERENCES

Chathopadhyaya, S, 2004, Landforms of Kerala: an overview, in Earth system sciences andNatural resource Management, (ed.) Ravindrakumar, G.R., and Subhash, N.,CESS, 2004, p211-228

Najeeb, K.Md., 1999, Ground water exploration in Kerala as on 31-3-1999: CGWB, KeralaRegion, Trivandum, (unpublished report)

Soman, K, 2002, Geology of Kerala, Geological Society of India, Bangalore, 335p.Varadarajan and Balakrishnan,1980,

Thrivikramji,K.P., 1986, River metamorphosis due to Human intervention: A Neyyar basinexperience: Final report submitted to MOE&F, GoI, 156p.

Thrivikramji, K.P. and Anirudhan, S., 1992, Sea level rise due to Green house Effect: Reportsubmitted to MOE&F, GoI, New Delhi, 56p

Varadarajan, K, and Balakishnan, M.K., 1980, Kerala coast A LANDSAT view: in Geologyand Geomorphology of Kerala, Geological Survey of India, Sp. Pub., no.5, 67-68.

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