Meghalaya - Ministry of Environment and Forests

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Meghalaya - Ministry of Environment and Forests


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NATIONAL WETLAND ATLAS:MEGHALAYASponsored byMinistry of Environment and ForestsGovernment of IndiaSpace Applications centreIndian Space Research OrganisationAhmedabad – 380 015

This publication deals with the updated database andstatus of wetlands, compiled in Atlas format. Increasingconcern about how our wetlands are being influenced hasled to formulation of a project entitled “National WetlandInventory and Assessment (NWIA)” to create an updateddatabase of the wetlands of India. The wetlands arecategorised under 19 classes and mapped using satelliteremote sensing data from Indian Remote SensingSatellite: IRS P6- LISS III sensor. The results areorganised at 1: 50, 000 scales at district, state andtopographic map sheet (Survey of India reference) levelusing Geographic Information System (GIS). Thispublication is a part of this national work and deals withthe wetland status of a particular State/Union Territory ofIndia, through text, statistical tables, satellite images,maps and ground photographs.The atlas comprises wetland information arranged intonine sections. How the NWIA project work has beenexecuted highlighted in the first six sections viz:Introduction, NWIA project, Study area, Data used,Methodology, and Accuracy. This is the first time that highresolution digital remote sensing data has been used tomap and decipher the status of the wetlands at nationalscale. The methodology highlights how the four spectralbands of LISS III data (green, red, near infra red and shortwave infra red) have been used to derive various indicesand decipher information regarding water spread,turbidity and aquatic vegetation. Since, the aim was togenerate a GIS compatible database, details of thestandards of database are also highlighted in themethodology.The results and finding are organised in three sections;viz: Maps and Statistics, Major wetland types, andImportant Wetlands of the area. The Maps and Statisticsare shown for state and district level. It gives details ofwhat type of wetlands exists in the area, how manynumbers in each type, their area estimates in hectare.Since, the hydrology of wetlands are influenced bymonsoon performance, extent of water spread and theirturbidity (qualitative) in wet and dry season (postmonsoonand pre-monsoon period) are also given.Similarly the status of aquatic vegetation (mainly floatingand emergent types) in two seasons is also accounted for.Status of small wetlands are also accounted as numbersand depicted in maps as points. Wetland map also showimportant ancillary information like roads/rail, relevanthabitations. False Colour Composite (FCC) of the satelliteimage used (any one season) is shown along with thederived wetland map to give a feeling of manifestation ofwetlands in remote sensing data and synoptic view of thearea. The status of some of the important wetlands likeRamsar sites, National Parks are shown with recent fieldphotographs.For further details contact:Director,Space Applications Centre, ISRO,Ambawadi Vistar (P.O.)Ahmedabad – 380 015director@sac.isro.gov.in

AtlasSAC/RESA/AFEG/NWIA/ATLAS/02/2009NATIONAL WETLAND ATLASMeghalayaSponsored byMinistry of Environment and Forests, Government of IndiaAs a part of the project on National Wetland Inventory and Assessment (NWIA)Space Applications Centre (ISRO), AhmedabadandNorth Eastern Space Applications Centre, Umiam, MeghalayaMay 2009

First Publication: May 2009, Space Applications Centre (ISRO), AhmedabadCopyright:2009, SAC, ISROThis publication may be produced in whole or in part and in any form for education or non-profit uses,without special permission from the copyright holder, provided acknowledgement of source is made. SACwill appreciate a copy of any publication which uses this publication as a source.Citation:Available from:Production:National Wetland Atlas: Meghalaya, SAC/RESA/AFEG/NWIA/ATLAS/02/2009, Space ApplicationsCentre(ISRO), Ahmedabad, India, 88p.Space Applications Centre, ISRO, Ahmedabad – 380 015, IndiaSAC carried out the work in collaboration with NESAC, Shillong, Sponsored by Ministry of Environment andForests, Govt. of India.

MESSAGEIt gives me great pleasure to introduce this Atlas, the latest in a series, prepared by Space ApplicationsCentre, Ahmedabad in connection with the National Wetland Inventory and Assessment Project.This Atlas maps and catalogues information on Wetlands across India using the latest in satellite imaging,one of the first of its kind. Wetlands are areas of land critical ecological significance that support a largevariety of plant and animal species adapted to fluctuating water levels. Their identification and protectionbecomes very important.Utility-wise, wetlands directly and indirectly support millions of people in providing services such as food,fiber and raw materials. They play important roles in storm and flood control, in supply of clean water, alongwith other educational and recreational benefits. Despite these benefits, wetlands are the first target ofhuman interference and are among the most threatened of all natural resources. Around 50% of theearth’s wetlands are estimated to already have disappeared worldwide over the last hundred years throughconversion to industrial, agricultural and residential purposes. Even in current scenario, when theecosystem services provided by wetlands are better understood - degradation and conversion of wetlandscontinues.Aware of their importance, the Government of India has formulated several policies and plans for theconservation and preservation of these crucial ecosystems. Realising the need of an updated geospatialdata base of these natural resources as the pre-requisite for management and conservation planning,National Wetland Inventory and Assessment (NWIA) project was formulated as a joint vision of Ministry ofEnvironment & Forestry, Govt. India, and Space Applications Centre (ISRO). I am told that the latestremote sensing data from Indian Remote Sensing satellite (IRS P6) have been used to map the wetlands.The present atlas is part of this project and highlights the results of the study state in terms of statistics ofvarious types of wetlands, extent of water, aquatic vegetation and turbidity in pre and post monsoon period.I also note that special efforts are made to provide detailed information of important wetlands like Ramsarsites, National Parks etc.I am certain that this Atlas will raise the bar in developing such database and will be of great use forresearchers, planners, policy makers, and also members of the general public.

FOREWORDWetlands defined as areas of land that are either temporarily or permanently covered by water exhibitenormous diversity according to their genesis, geographical location, water regime and chemistry. Wetlandsare one of the most productive ecosystems and play crucial role in hydrological cycle. Utility wise, wetlandsdirectly and indirectly support millions of people in providing services such as storm and flood control, cleanwater supply, food, fiber and raw materials, scenic beauty, educational and recreational benefits. TheMillennium Ecosystem Assessment estimates conservatively that wetlands cover seven percent of the earth’ssurface and deliver 45% of the world’s natural productivity and ecosystem services. However, the veryexistence of these unique resources is under threat due to developmental activities, and population pressure.This calls for a long term planning for preservation and conservation of these resources. An updated andaccurate database that will support research and decision is the first step towards this. Use of advancedtechniques like Satellite remote sensing, Geographic Information System (GIS) is now essential for accurateand timely spatial database of large areas. Space Applications Centre (ISRO) took up this challenging taskunder the project “NWIA” (National Wetland Inventory and Assessment) sponsored by Ministry ofEnvironment & Forests. To account for numerous small yet important wetlands found in the country, mappingat 1:50,000 scales has been taken up. Two date IRS LISS III data acquired during pre and post monsoonseason are used for inventory to account for wet and dry season hydrology of wetlands. The map outputsinclude the status of water spread, aquatic vegetation and turbidity. Ancillary layers like road/rail, habitationsare also created. Very small wetlands below the mappable unit are also identified and shown points. Theresults are complied as Atlases of wetlands for states/Union Territories of India. This Atlas highlights resultsfor a particular state/UT and hopes to improve our understanding of the dynamics and distribution of wetlandsand their status in the area.I congratulate the team for bringing out this informative atlas and sincerely hope that this will serve as auseful source of information to researchers, planners and general public.January 25, 2010

PROJECT TEAMProject Director: Dr. (Mrs.) Sushma PanigrahySpace Applications Centre, ISRO, AhmedabadShri J. G. PatelDr. T. S. SinghShri T. V. R MurthyNorth Eastern Space Applications Centre, Umiam, MeghalayaMs. Kasturi Chakraborty

CONTENTS1.0 INTRODUCTION1.1 Wetlands1.2 Mapping and geospatial techniques1.3 Wetland Inventory of India2.0 NATIONAL WETLAND INVENTORY AND ASSESSMENT2.1 Wetland Classification System2.2 GIS database contents3.0 STUDY AREA4.0 DATA USED5.0 METHODOLOGY5.1 Creation of spatial framework5.2 Geo-referencing of satellite data5.3 Mapping of wetlands5.4 Conversion of the conformation into a vector layer5.5 Generation of reference layers5.6 Coding and attribute scheme5.7 Map composition and output6.0 ACCURACY ASSESSMENT7.0 WETLANDS OF MEGHALAYA: MAPS AND STATISTICS7.1 District-wise Wetland Maps and Statistics8.0 MAJOR WETLAND TYPES9.0 IMPORTANT WETLANDS OF MEGHALAYA10.0 SOI-MAPSHEET WISE WETLAND MAPS (selected sheets)ReferencesAnnexure–I: Definitions of wetland categories used in the project.Annexure–II: Details of district information followed in the atlasList of FiguresFigure 1: Spectral Signature of various targetsFigure 2: Various land features as they appear in four spectral bands and in a typical three band FCC.Figure 3: Location mapFigure 4: Spatial framework of MeghalayaFigure 5: IRS P6 LISS-III coverage of MeghalayaFigure 6 : IRS LISS-III FCC (25 March 2007 and 25 November 2007)Figure 7: Flow chart of the methodology usedFigure 8: Steps in the extraction of wetland componentsFigure 9: Various combinations of the indices/spectral bands used to identify wetland componentsFigure 10: Type-wise wetland distribution in MeghalayaFigure 11: District-wise wetland distributionList of TablesTable 1: Wetland Classification System and codingTable-2: Satellite data usedTable 3: Qualitative turbidity ratingsTable 4: Area estimates of wetlands in MeghalayaTable-5: District-wise wetland areaTable 6: Area estimates of wetlands in West Garo HillsTable 7: Area estimates of wetlands in East Garo Hills

Table 8: Area estimates of wetlands in South Garo HillsTable 9: Area estimates of wetlands in West Khasi HillsTable 10: Area estimates of wetlands in Ri BhoiTable 11: Area estimates of wetlands in East Khasi HillsTable 12: Area estimates of wetlands in Jaintia HillsList of PlatesPlate-1: Major wetland types of MeghalayaPlate-2a and 2b : Field photographs and ground truth data of different wetland types in MeghalayaPlate 3: Umiam lakePlate 4: Wetland map - 5 km buffer area of Umiam lakePlate 5: Nongkhnum river IslandPlate 6: Wetland map - 5 km buffer area of Nongkhnum river IslandPlate 7: RanikorPlate 8: Wetland map - 5 km buffer area of Ranikor

1.0 INTRODUCTIONIt is increasingly realized that the planet earth is facing grave environmental problems with fast depletingnatural resources and threatening the very existence of most of the ecosystems. Serious concerns are voicedamong scientists, planners, sociologists, politicians, and economists to conserve and preserve the naturalresources of the world. One of the difficulties most frequently faced for decision making is lack of scientificdata of our natural resources. Often the data are sparse or unconvincing, rarely in the form of geospatialdatabase (map), thus open to challenges. Thus, the current thrust of every country is to have an appropriategeospatial database of natural resources that is based on unambiguous scientific methods. The wetland atlasof Meghalaya, which is part of the National Wetland Atlas of India, is an attempt in this direction.1.1 WetlandsWetlands are one of the crucial natural resources. Wetlands are areas of land that are either temporarily orpermanently covered by water. This means that a wetland is neither truly aquatic nor terrestrial; it is possiblethat wetlands can be both at the same time depending on seasonal variability. Thus, wetlands exhibitenormous diversity according to their genesis, geographical location, water regime and chemistry, dominantplants and soil or sediment characteristics. Because of their transitional nature, the boundaries of wetlandsare often difficult to define. Wetlands do, however, share a few attributes common to all forms. Of these,hydrological structure (the dynamics of water supply, throughput, storage and loss) is most fundamental tothe nature of a wetland system. It is the presence of water for a significant period of time which is principallyresponsible for the development of a wetland. One of the first widely used classifications systems, devised byCowardin et al., (1979), was associated to its hydrological, ecological and geological aspects, such as:marine (coastal wetlands including rock shores and coral reefs, estuarine (including deltas, tidal marshes, andmangrove swamps), lacustarine (lakes), riverine (along rivers and streams), palustarine ('marshy'- marshes,swamps and bogs). Given these characteristics, wetlands support a large variety of plant and animal speciesadapted to fluctuating water levels, making the wetlands of critical ecological significance. Utility wise,wetlands directly and indirectly support millions of people in providing services such as food, fiber and rawmaterials, storm and flood control, clean water supply, scenic beauty and educational and recreationalbenefits. The Millennium Ecosystem Assessment estimates conservatively that wetlands cover seven percentof the earth’s surface and deliver 45% of the world’s natural productivity and ecosystem services of which thebenefits are estimated at $20 trillion a year (Source : www.MAweb.org). The Millennium Assessment (MA)uses the following typology to categorise ecosystem services:Provisioning services: The resources or products provided by ecosystems, such as food, raw materials(wood), genetic resources, medicinal resources, ornamental resources (skin, shells, flowers).Regulating services: Ecosystems maintain the essential ecological processes and life support systems, likegas and climate regulation, water supply and regulation, waste treatment, pollination, etc.Cultural and Amenity services: Ecosystems are a source of inspiration to human culture and educationthroughout recreation, cultural, artistic, spiritual and historic information,science and education.Supporting services: Ecosystems provide habitat for flora and fauna in order to maintain biological andgenetic diversity.Despite these benefits, wetlands are the first target of human interference and are among the mostthreatened of all natural resources. Around 50% of the earth’s wetlands is estimated to already havedisappeared worldwide over the last hundred years through conversion to industrial, agricultural andresidential developments. Even in current scenario, when the ecosystem services provided by wetlands arebetter understood - degradation and conversion of wetlands continues. This is largely due to the fact that the‘full value’ of ecosystem functions is often ignored in policy-making, plans and corporate evaluations ofdevelopment projects.1.2 Mapping and Geospatial techniqueTo conserve and manage wetland resources, it is important to have inventory of wetlands and theircatchments. The ability to store and analyse the data is essential. Digital maps are very powerful tools toachieve this. Maps relate the feature to any given geographical location has a strong visual impact. Maps,thus essential for monitoring and quantifying change over time scale, assist in decision making. Thetechnique used in the preparation of map started with ground survey. The Survey of India (SOI) topographicmaps are the earliest true maps of India showing various land use/cover classes including wetlands. Recentyears have seen advances in mapping technique to prepare maps with much more information. Of particularimportance is the remote sensing and geographic information system (GIS) technique. Remote sensing is1

now recognized as an essential tool for viewing, analyzing, characterizing, and making decisions about land,water and atmospheric components.From a general perspective, remote sensing is the science of acquiring and analyzing information aboutobjects or phenomena from a distance (Jensen, 1986; Lillesand and Keifer, 1987). Today, we define satelliteremote sensing as the use of satellite borne sensors to observe, measure, and record the electromagneticradiation (EMR) reflected or emitted by the earth and its environment for subsequent analysis and extractionof information. EMR sensors includes visible light, near-, mid- and far-infrared (thermal), microwave, andlong-wave radio energy. The capability of multiple sources of information is unique to remote sensing. Ofspecific advantage is the spectral, temporal, and spatial resolution. Spectral resolution refers to the width orrange of each spectral band being recorded. Since each target affects different wavelengths of incidentenergy differently, they are absorbed, reflected or transmitted in different proportions. Currently, there aremany land resource remote sensing satellites that have sensors operating in the green, red, near infraredand short wave Infra red regions of the electromagnetic spectrum giving a definite spectral signature ofvarious targets due to difference in radiation absorption and reflectance of targets. These sensors are ofcommon use for land cover studies, including wetlands. Figure 1 shows typical spectral signature of fewtargets from green to SWIR region. Converted to image, in a typical false colour composite (FCC) createdusing NIR, red and green bands assigned as red, green and blue colour, the features become very distinct asshown in Figure 2. In FCC, the vegetation thus appears invariably red (due to high reflection in NIR fromgreen leaves).Since the early 1960s, numerous satellite sensors have been launched into orbit to observe and monitor theearth and its environment. Most early satellite sensors acquired data for meteorological purposes. The adventof earth resources satellite sensors (those with a primary objective of mapping and monitoring land cover)occurred, when the first Landsat satellite was launched in July 1972. Currently, more than a dozen orbitingsatellites of various types provide data crucial to improving our knowledge of the earth’s atmosphere, oceans,ice and snow, and land. Of particular interest to India is the indigenous series of satellites called IndianRemote Sensing (IRS) satellites. Since the launch of the first satellite IRS 1A in 1987, India has now anumber of satellites providing data in multi-spectral bands with different spatial resolution. IRSP6/RESOURCESAT 1 is the current generation satellite that provides multi-spectral images in spatialresolution of 5.8 m (LISS IV), 23.5 m (LISS III) and 56m (AWiFS). Over the past few decades, Indian remotesensing data has been successfully used in various fields of natural resources ( Navalgund et al. 2002).Development of technologies like Geographic Information System (GIS) has enhanced the use of RS data toobtain accurate geospatial database. GIS specialises in handling related, spatially referenced data, combiningmapped information with other data and acts as analytical tool for research and decision making. During thepast few decades, technological advances in the field of satellite remote sensing (RS) sensors, computerizedmapping techniques, global positioning system (GPS) and geographic information system (GIS) hasenhanced the ability to capture more detailed and timely information about the natural resources at variousscales catering to local, regional, national and global level study.Figure 1: Spectral Signature of various targets2

REDGREENNIR RED GREENNIRIRS LISS III FCCSWIRFigure 2: Various land features as they appear in four spectral bands and in a typical three band FCC.3

1.3 Wetland Inventory of IndiaIndia with its large geographical spread supports large and diverse wetland classes, some of which areunique. Wetlands, variously estimated to be occupying 1-5 per cent of geographical area of the country,support about a fifth of the known biodiversity. Like any other place in the world, there is a looming threat tothe aquatic biodiversity of the Indian wetlands as they are often under a regime of unsustainable humanpressures. Sustainable management of these assets therefore is highly relevant. Realising this, Govt. of Indiahas initiated many appropriate steps in terms of policies, programmes and plans for the preservation andconservation of these ecosystems. India is a signatory to the Ramsar Convention for management ofwetland, for conserving their biodiversity and wise use extending its scope to a wide variety of habitats,including rivers and lakes, coastal lagoons, mangroves, peatlands, coral reefs, and numerous human-madewetland, such as fish and shrimp ponds, farm ponds, irrigated agricultural land, salt pans reservoirs, gravelpits, sewage farms, and canals. The Ministry of Environment and Forests has identified a number of wetlandsfor conservation and management under the National Wetland Conservation Programme and some financialassistance is being provided to State Governments for various conservation activities through approval of theManagement Action Plans. The need to have an updated map database of wetlands that will support suchactions has long been realized.Mapping requires a standard classification system. Though there are many classification systems forwetlands in the world, the Ramsar classification system is the most preferred one. The 1971 RamsarConvention on Wetlands of International Importance especially as Waterfowl Habitat is the oldestconservation convention. It owes its name to its place of adoption in Iran. It came into being due to seriousdecline in populations of waterfowl (mainly ducks) and conservation of habitats of migratory waterfowl.Convention provides framework for the conservation and ‘wise use’ of wetland biomes. Ramsar convention isthe first modern global intergovernmental treaty on conservation and wise use of natural resources(www.ramsar.org). Ramsar convention entered into force in 1975. Under the text of the Convention (Article1.1) wetlands are defined as:“areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water thatis static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide doesnot exceed six meters”.In addition, the Convention (Article 2.1) provides that wetlands:“may incorporate riparian and coastal zones adjacent to the wetlands, and islands or bodies of marine waterdeeper than six meters at low tide lying within the wetlands”.The first scientific mapping of wetlands of India was carried out during1992-93 by Space Applications Centre(ISRO), Ahmedabad, at the behest of the Ministry of Environment and Forests (MoEF), Govt. of India usingremote sensing data from Indian Remote Sensing (IRS) satellite. The mapping was done at 1:250,000 scaleusing IRS 1A LISS-I/II data of 1992-93 timeframe under the Nation-wide Wetland Mapping Project. Since, nosuitable wetland classification existed for comprehensive inventory of wetlands in the country at that time, theproject used a classification system based on Ramsar Convention definition of wetlands. The classificationconsiders all parts of a water mass including its ecotonal area as wetland. In addition, fish and shrimp ponds,saltpans, reservoirs, gravel pits were also included as wetlands. This inventory put the wetland extent (inlandas well as coastal) at about 8.26 million ha. (Garg et al). These estimates (24 categories) do not includerice/paddy fields, rivers, canals and irrigation channels.Further updating of wetland maps of India was carried out by SAC using IRS P6/Resourcesat AWiFS data of2004-05 at 1:250000 scale. In recent years, a conservation atlas has been brought out by Salim Ali Centre forOrnithology and Natural History (SACON, 2004), which provide basic information required by stakeholders inboth wetland habitat and species conservation. Space Applications Centre has carried out many pilot projectsfor development of GIS based wetland information system (Patel et al, 2003) and Lake Information system(Singh et al, 2003).4

2.0 NATIONAL WETLAND INVENTORY AND ASSESSMENT (NWIA) PROJECTRealising the importance of many small wetlands that dot the Indian landscape, it has been unanimously feltthat inventory of the wetlands at 1:50,000 scale is essential. The task seemed challenging in view of the vastgeographic area of our country enriched with diverse wetland classes. Space Applications Centre with itsexperience in use of RS and GIS in the field of wetland studies, took up this challenging task. This is furtherstrengthened by the fact that guidelines to create geospatial framework, codification scheme, data basestructure etc. for natural resources survey has already been well established by the initiative of ISRO undervarious national level mapping projects. With this strength, the National Wetland Inventory and Assessment(NWIA) project was formulated by SAC, which was approved and funded by MoEF.The main objectives of the project are:• To map the wetlands on 1:50000 scale using two date (pre and post monsoon) IRS LISS III digital datafollowing a standard wetland classification system.• Integration of ancillary theme layers ( road, rail, settlements, drainage, administrative boundaries)• Creation of a seamless database of the states and country in GIS environment.• Preparation of State-wise wetland atlasesThe project was initiated during 2007. The first task was to have a classification system that can be used bydifferent types of users while amenable to database. An expert/peer group was formed and the peer reviewwas held at SAC in June 2007 where wetland experts and database experts participated and finalized theclassification system. It was agreed to follow the classification system that has been used for the earlierproject of 1:250,000 scale, with slight modification. Modified National Wetland Classification system forwetland delineation and mapping comprise 19 wetland classes which are organized under a Level IIIhierarchical system. The definition of each wetland class and its interpretation method was finalized. Thetechnical/procedure manual was prepared as the standard guideline for the project execution across thecountry (Garg and Patel, 2007). The present atlas is part of the national level data base and deals with thestate of Meghalaya.2.1 Wetland Classification SystemIn the present project, Modified National Wetland Classification system is used for wetland delineation andmapping comprising 19 wetland classes which are organized under a Level III hierarchical system (Table 1).Level one has two classes: inland and coastal, these are further bifurcated into two categories as: natural andman-made under which the 19 wetland classes are suitably placed. Two date data pertaining to pre-monsoonand post monsoon was used to confirm the classes. Wetlands put to agriculture use in any of the two datesare not included as wetland class. Definitions of wetland categories used in the project is given in Annexure-I.2.2.1 Spatial Framework and GIS DatabaseThe National Spatial Framework) (NSF) has been used as the spatial framework to create the database(Anon. 2007). The database design and creation standard suggested by NRDB/NNRMS guidelines isfollowed. Feature codification scheme for every input element has been worked out keeping in view thenationwide administrative as well as natural hierarchy (State-district- within the feature class for each of thetheme. All data elements are given a unique name, which are self explanatory with short forms.Following wetland layers are generated for each inland wetland:• Wetland extent: As wetlands encompass open water, aquatic vegetation (submerged, floating andemergent), the wetland boundary should ideally include all these. Satellite image gives a clear signatureof the wetland extent from the imprint of water spread over the years.• Water spread: There are two layers representing post-monsoon and pre-monsoon water spread duringthe year of data acquisition.• Aquatic vegetation spread: The presence of vegetation in wetlands provides information about itstrophic condition. As is known, aquatic vegetation is of four types, viz. benthic, submerged, floating,and emergent. It is possible to delineate last two types of vegetation using optical remote sensing data.A qualitative layer pertaining to presence of vegetation is generated for each season (as manifested onpre-monsoon and post-monsoon imagery).5

• Turbidity level of open water: A layer pertaining to a qualitative turbidity rating is generated. Threequalitative turbidity ratings ( low, medium and high) is followed for pre and post-monsoon turbidity oflakes, reservoirs, barrages and other large wetlands.• Small wetlands (smaller than minimum mappable unit) are mapped as point features.• Base layers like major road network, railway, settlements, and surface drainage are created (eitherfrom the current image or taken from other project data base).In the case of coastal wetlands only wetland extent is given.Table 1: Wetland Classification System and coding (Annexure I for more details)Wettcode* Level I Level II Level III1000 Inland Wetlands1100 Natural1101 Lakes1102 Ox-Bow Lakes/ Cut-Off Meanders1103 High altitude Wetlands1104 Riverine Wetlands1105 Waterlogged1106 River/stream1200 Man-made1201 Reservoirs/ Barrages1202 Tanks/Ponds1203 Waterlogged1204 Salt pans2000 CoastalWetlands2100 Natural2101 Lagoons2102 Creeks2103 Sand/Beach2104 Intertidal mud flats2105 Salt Marsh2106 Mangroves2107 Coral Reefs2200 Man-made2201 Salt pans2202 Aquaculture ponds* Wetland type code6

3.0 STUDY AREAMeghalaya occupies the western position of the North eastern region. The North Eastern state of Meghalayatheabode of clouds is predominantly a land of hills and valley. Owing to its natural beauty and grace it hasbeen also named as ‘Scotland of the East’. Geographical location of the state is between 89 o 45’ to 92 o 48’and 25 o 02’ to 26 o 05’. The total geographical area of the state is 22, 429 Sq Km, extending 300 km west toeast and 100 km from north to south.It is bounded on the north by Goalpara and Kamrup district of Assam, on the east by North Cachar and KarbiAnglong, the Western and Southern boundary is the International border between India and Bangladesh. Theprevailing climate in the state is characterized by heavy rainfall, which favors the action of streams to aconsiderable extent.The geological formations, its resultant topography and tendency of headword erosion by rain water havelead to the creation of drainage network in Meghalaya. The state is blessed with number of perennial rivers.The principal rivers of the state run either a Northerly or Southerly direction. Satellite imagery identifies theadaptation of streams along major and minor lineaments. The rivers flowing towards the north to meet mightyBrahmaputra river of Assam plain have gentle gradient of longitudinal profiles and thereby do not form anymajor waterfalls and deep gorges. The rivers flowing towards the south are characterized by steepestgradient and abruptly falls to the Bangladesh plain.The capital of Meghalaya state is in Shillong. There are total seven districts of Meghalaya state. The districtsderive their names from that of the tribes inhabiting the region. The seven districts are: East Khasi hills, Eastgaro hills, Jaintia hills, Ri Bhoi, South Garo hills,West Garo hills and West Khasi hills (Statistical hand book ofMeghalaya, 2007) . There are about 5,782 villages in the state. The total population of the state is 2,318, 822(Manorama year book 2009).The major rivers of the state are Ganol, Ringgi, Krishnai, Manda, Darong, Bhogai, simsang, Dareng, Umkhri,Umtrew, Umiam, Kopili, Kynshiang,Shella, Umngot, Myntdu, Lubha, etc. One of the marked features of RiverKynshi in West Khasi Hills is the formation of River Island called Nongkhnum. Nongkhnum is not only India’sbut Asia’s second largest river island. Ranikor situated in the West Khasi Hills district in the confluence ofKynshi and Rilang rivers is one of the best fishing spots. Meghalaya has the highest hydro – electric potentialin the north-eastern region second only to Auranachal Pradesh. Hydel projects such as Umiam and Umtrewhave caused construction of artificial lakes for the generation of electricity. Umiam Lake commonly calledBarapani is formed by the damming of the Umiam river under the Umiam Hydro-Electric Project is a place ofmajor tourist attraction and has great potentialities of recreation, aquatic sports, fishing etc. Meghalaya is alsonoted for a number of river cataracts and waterfall of great beauty located at different heights and scenicsetting.The state is covered by 54 Survey of India topographical maps on 1:50,000 scale that spatial framework formapping (Figure 4). The spatial framework was prepared using 15’x15’ grid.7

Figutr 3: Location mapFigure 4: Spatial Framework of Meghalaya8

4.0 DATA USEDRemote sensing dataIRS P6 LISS III data was used to map the wetlands. IRS P6 LISS III provide data in 4 spectral bands; green,red, Near Infra Red (NIR) and Short wave Infra Red (SWIR), with 23 m spatial resolution and 24 day repeatcycle. The spatial resolution is suitable for 1:50,000 scale mapping. The state of Meghalaya is covered in 6IRS LISS III scene (Figure 5). Two date data, one acquired during March and another during January wereused to capture the pre-monsoon and post-monsoon hydrological variability of the wetlands respectively(Table-2). Figure 6 shows part of Meghalaya as seen in the LISS III FCC of post- monsoon pre-monsoon datarespectively.Figure 5: IRS P6 LISS-III coverage (path-row) of MeghalayaTable-2: Satellite data usedSl.NoResourcesat LISS IIIPath/ RowPost-MonsoonPre-Monsoon1 109/53 Oct 27, 2006 Mar 20, 20072 109/54 Oct 27, 2006 Mar 20, 20073 110/53 Dec 14, 2007 Mar 25, 20074 110/54 Dec 19, 2006 Feb 10,20065 111/53 Nov 25, 2007 Jan 22, 20066 111/54 Nov 30, 2006 Mar 30, 2007Ground truth dataRemote sensing techniques require certain amount of field observation called “ground truth” in order toconvert into meaningful information. Such work involves visiting a number of test sites, usually taking thesatellite data. The location of the features is recorded using the GPS. The standard proforma as per theNWIA manual was used to record the field data. Field photographs are also taken to record the water quality(subjective), status of aquatic vegetation and water spread. All field verification work has been done duringOctober and November 2008.Other dataSurvey of India topographical maps (SOI) were used for reference purpose. Lineage data of National WetlandMaps at 1:50,000 scale was used for reference.9

5.0 METHODOLOGYThe methodology to create the state level atlas of wetlands is adhered to NWIA technical guidelines andprocedure manual (Garg and Patel, 2007). The overview of the steps used is shown in Figure 7. Salientfeatures of methodology adopted are• Generation of spatial framework in GIS environment for database creation and organisation.• Geo-referencing of satellite data• Identification of wetland classes as per the classification system given in NWIA Manual and mapping ofthe classes using a knowledge based digital classification and onscreen interpretation• Generation of base layers (rail, road network, settlements, drainage, administrative boundaries) fromsatellite image and ancillary data.• Mosaicing/edge matching to create district and state level database.• Coding of the wetlands following the standard classification system and codification as per NWIAmanual.• Preparation of map compositions and generation of statistics• Outputs on A3 size prints and charts for atlas.Work was carried out using ERDAS Imagine, Arc/Info and ArcGIS softwares.5.1 Creation of spatial frameworkThis is the most important task as the state forms a part of the national frame work and is covered in multiplemap sheets. To create NWIA database, NNRMS/NRDB standards is followed and four corners of the1:50,000 (15’ x 15’) grid is taken as the tics or registration points to create each map taking master grid as thereference. Spatial framework details are given in NWIA manual (Garg and Patel, 2007). The spatialframework for Meghalaya state is shown in Figure 4.5.2 Geo-referencing of satellite dataIn this step the raw satellite images were converted to specific map projection using geometric correction.This is done using archived geometrically corrected LISS III data (ISRO-NRC-land use / land cover project).Standard image processing software was used for geo-referencing. First one date data was registered withthe archived image. The second date data was then registered with the first date data.5.3 Mapping of wetlandsThe delineation of wetlands through image analysis forms the foundation for deriving all wetland classes andresults. Consequently, a great deal of emphasis has been placed on the quality of the image Interpretation. Inthe present study, the mapping of wetlands was done following digital classification and onscreen visualinterpretation. Wetlands were identified based on vegetation, visible hydrology and geography. There arevarious methods for extraction of water information from remote sensing imagery, which according to thenumber of bands used, are generally divided into two categories, i.e. Single-band and multi-band methods.Single-band method usually involves choosing a band from multi-spectral image to distinguish water fromland by subjective threshold values. It may lead to over- or under-estimation of open water area. Multi-bandmethod takes advantage of reflective differences of each band. In this project, five indices known in literaturethat enhances various wetland characteristics were used (McFeetres, 1986; Xu Hanqiu, 2006; Lacaux et al,2007; Townshend and Justice, 1986; Tucker and Sellers, 1986) as given below:i) Normalised Difference Water Index (NDWI) = (Green-NIR) / (Green + NIR)ii) Modified Normalised Difference Water Index (MNDWI) = (Green-MIR) / (Green + MIR)iii) Normalised Difference Vegetation Index (NDVI) = (NIR - Red) / (NIR + Red)iv) Normalised Difference Pond Index (NDPI) = (MIR – Green / MIR + Green)v) Normalised Difference Turbidity Index (NDTI) = (Red – Green) / (Red + Green)The indices were generated using standard image processing software, stacked as layers. (Figure 8). Variouscombinations of the indices/spectral bands were used to identify the wetland features as shown in Figure 9.10

25 March 200725 November 2007Figure 6: IRS LISS-III FCC showing part of Meghalaya (pre-monsoon and post-monsoon satellite images)11

IRS P6 LISS IIIpre and post-monsoon dataSpatial frame workLegacy dataAdmin. Boundaries(State, District)Geo-referenced imagesOn-screen interpretation/Digital analysisSOI topographic mapsGround truthMorphometric(Wetland extent)Physical(Wetland type)Biological(Wetland vegetation)Base layers(Road, Settlement, drainage)Quality CheckGIS DATABASE(Wetland layers, Base layers)NWIA Database Organisation(District, State, Country)Accuracy Assessment/Quality CheckAnalysisAtlases/ReportFigure 7: Flow chart of the methodology usedThe following indices were used for various layer extractions:• Extraction of wetland extent :MNDWI, NDPI and NDVI image was used to extract the wetland boundary through suitable hierarchicalthresholds.• Extraction of open water :MNDWI was used within the wetland mask to delineate the water and no-water areas.• Extraction of wetland vegetation :NDPI and NDVI image was used to generate the vegetation and no-vegetation areas within a wetlandusing a suitable threshold.• Turbidity information extraction :NDTI and MNDWI image was used to generate qualitative turbidity level (high, moderate and low)based on signature statistics and standard deviations. In the False Colour Composite (FCC) thesegenerally appear in different hues as given in Table-3.Table 3: Qualitative turbidity ratingsSr. No. Qualitative Turbidity Conditional criteria Hue on False Colour Composite (FCC)1. Low > +1σ Dark blue/blackish2. Moderate > -1σ to

Figure 8: Steps in the extraction of wetland components5.4 Conversion of the raster (indices) into a vector layerThe information on wetland extent, open water extent, vegetation extent and turbidity information wasconverted into vector layers using region growing properties or on-screen digitisation.5.5 Generation of reference layersBase layers like major rail, road network, settlements, drainage are interpreted from the current image ortaken from other project database. The administrative boundaries (district, state) are taken from the knownreference data.5.6 Coding and attribute schemeFeature codification scheme for every input element has been worked out keeping in view the nationwideadministrative as well as natural hierarchy (State-district-taluka) within the feature class for each of the theme.All data elements are given a unique name/code, which are self explanatory with short forms.5.7 Map composition and outputMap composition for atlas has been done at district and state level. A standard color scheme has been usedfor the wetland classes and other layers. The digital files are made at 1:50,000 scale. The hard copy outputsare taken on A3 size.13

6.0 ACCURACY ASSESSMENTA comprehensive accuracy assessment protocol has been followed for determining the quality of informationderived from remotely sensed data. Accuracy assessment involves determination of thematic (classification)as well as locational accuracy. In addition, GIS database(s) contents have been also evaluated for accuracy.To ensure the reliability of wetland status data, the project adhered to established quality assurance andquality control measures for data collection, analysis, verification and reporting.This study used well established, time-tested, fully documented data collection conventions. It employedskilled and trained personnel for image interpretation, processing and digital database creation. All interpretedimageries were reviewed by technical expert team for accuracy and code. The reviewing analyst adhered toall standards, quality requirements and technical specifications and reviewed 100 percent of the work. Thevarious stages of quality check include:1. Image-to-Image Geo-referencing/Data generation2. Reference layer preparation using NWIA post monsoon and pre-monsoon LISS-III data.3. Wetland mapping using visual/digital interpretation techniques.4. Geo-data base creation and organization5. Output products.6.1 Data verification and quality assurance of output digital data filesAll digital data files were subjected to rigorous quality control inspections. Digital data verification includedquality control checks that addressed the geospatial correctness, digital integrity and some cartographicaspects of the data. Implementation of quality checks ensured that the data conformed to the specifiedcriteria, thus achieving the project objectives. There were tremendous advantages in using newertechnologies to store and analyze the geographic data. The geospatial analysis capability built into this studyprovided a complete digital database to better assist analysis of wetland change information. All digital datafiles were subjected to rigorous quality control inspections. Automated checking modules incorporated in thegeographic information system (Arc/GIS) were used to correct digital artifacts including polygon topology.Additional customized data inspections were made to ensure that the changes indicated at the imageinterpretation stage were properly executed.14

Open waterMNDWI NDPI NDVIUseful for wetland boundary extraction/delineationG R NIRNDWI NDPI NDVIUseful for wetland vegetation & open water featuresG R SWIRLowHighLowThe Ox-Bow lakes and waterlogged areas adjacentto River in West Garo HillsIRS LISS III data, March 2007HighMNDWI MNDWI NDTIUseful for qualitative turbidity delineationFigure 9: Various combinations of the indices/spectral bands used to identify wetland components15


7.0 WETLANDS OF MEGHALAYA: MAPS AND STATISTICSArea estimates of various wetland categories for Meghalaya have been carried out using GIS layers ofwetland boundary, water-spread, aquatic vegetation and turbidity. In the state of Meghalaya, 259 (wetlandshave been delineated. Total wetland area estimated is 29987 ha. (Table 4). Small wetlands, which are lessthan minimum mapable units (MMU), are 167 in the district. The major wetland types are River/Stream(24841 ha) and Reservoirs (1562 ha). Graphical distribution of wetland type is shown in Figure 10.Sr.No.WettcodeTable 4 : Area estimates of wetlands in MeghalayaWetland CategoryNumberofWetlandsTotalWetlandArea% ofwetlandareaOpen WaterPostmonsoonAreaArea in haPremonsoonArea1100 Inland Wetlands - Natural1 1101 Lakes/Ponds 15 501 1.67 337 1752 1102 Ox-bow lakes/ Cut-off meanders 1 461 1.54 316 1073 1104 Riverine wetlands 4 1272 4.24 836 12714 1105 Waterlogged 77 1028 3.43 678 2805 1106 River/Stream 124 24841 82.84 24112 240511200 Inland Wetlands -Man-made6 1201 Reservoirs/Barrages 8 1562 5.21 1520 14157 1202 Tanks/Ponds 29 150 0.50 113 1218 1203 Waterlogged 1 5 0.02 - -Sub-Total 259 29820 99.44 27912 27420Wetlands (

7.1 DISTRICT-WISE WETLAND MAPS AND STATISTICSThe state has seven districts. District-wise wetland area estimates is given in Table-5.Wetland statistics followed by wetland map and corresponding satellite data for each district is given to havea fairly good idea about the distribution pattern and density of wetlands in the district.Table – 5: District-wise wetland areaGeographic Wetland % of total % of districtSr.DistrictArea Area wetland geographicNo.(sq. km) (ha) areaarea1 West Garo Hills 343890 7196 24.01 0.0212 East Garo Hills 286869 2649 8.84 0.0093 South Garo Hills 187083 3169 10.57 0.0174 West Khasi Hills 522543 5920 19.75 0.0115 Ri Bhoi 237005 1945 6.49 0.0086 East Khasi Hills 285216 4796 16.00 0.0177 Jaintia Hills 379347 4302 14.35 0.011Total 2241953 29977 100.00(* Source: Census 2001)West Garo Hills district of Meghalaya covers the maximum wetland area (24 %). A major portion of wetlandareas are observed in West khasi Hills, East Khasi Hills and in Jaintia Hills. East Garo Hills and Ribhoi districtcovers small portion of wetland area. The graphical distribution of district-wise wetland area is shown inFigure 11.Figure 11: District-wise wetland distribution20

7.1.1 Wetland Distribution in West Garo HillsWest Garo Hills is one of the largest districts of Meghalaya located in the western part of the State. The GaroHills district was divided into two districts, viz. the West Garo Hills district and the East Garo Hills district inOctober 1976. The erstwhile West Garo Hills district was further divided into two administrative districts ofWest and South Garo Hills on June 1992. The district headquarters of West Garo Hills is Tura, which is thesecond largest town in the State after Shillong. The West Garo Hills district is bounded by the East Garo Hillsdistrict on the east, the South Garo Hills on the south-east, the Goalpara district of Assam on the north andnorth-west and Bangladesh on the south. The total geographic area of West Garo Hills district of Meghalayais 343890 ha. The wetland area estimated is 7196 ha. Small wetlands, which are less than minimum mapableunits (MMU), are 99 in the district. Details are given in Table 6. The major wetland types are River/Stream,waterlogged areas, Lakes/Ponds and Ox-bow lakes.Sr.No.WettcodeTable 6: Area estimates of wetlands in West Garo HillsWetland CategoryNumberofWetlandsTotalWetlandArea% ofwetlandareaOpen WaterPostmonsoonAreaArea in haPremonsoonArea1100 Inland Wetlands - Natural1 1101 Lakes/Ponds 15 501 6.96 337 1752 1102 Ox-bow lakes/ Cut-off meanders 1 461 6.41 316 1073 1105 Waterlogged 74 1010 14.04 665 2684 1106 River/Stream 61 5083 70.64 5149 50871200 Inland Wetlands -Man-made5 1202 Tanks/Ponds 5 37 0.51 26 326 1203 Waterlogged 1 5 0.07 3 3Sub-Total 157 7097 98.62 6496 5672Wetlands (

7.1.7 Wetland Distribution in East Garo HillsThe East Garo Hills district was formed in 1976. The district was carved out from the Garo Hills District. Thedistrict headquarter is located at Williamnagar. As per 2001 census, the district is home to 2,50,582 people.Agriculture, horticulture, fisheries, textile, pottery, handicrafts, sericulture, cottage industries constitute theeconomic scenario of East Garo Hills. The topography of the district is undulating low hills, with altituderanging from 150 to 600 metres above sea level. The total geographic area of East Khasi Hills district ofMeghalaya is 286869 ha. The wetland area estimated is 2649 ha. Details are given in Table 7. Smallwetlands, which are less than minimum mapable units (MMU), are 14 in the district. The major wetland typesare River/Stream, tanks/ponds and areas under water logging. Other than the Simsang river which drainssoutheastwards, all other rivers run north or northwest towards the Brahmaputra.Sr.No.WettcodeTable 7: Area estimates of wetlands in East Garo HillsWetland CategoryNumberofWetlandsTotalWetlandArea% ofwetlandareaOpen WaterPostmonsoonAreaArea in haPremonsoonArea1100 Inland Wetlands - Natural1 1105 Waterlogged 3 18 0.68 12 122 1106 River/Stream 19 2563 96.75 2563 25631200 Inland Wetlands -Man-made3 1202 Tanks/Ponds 9 54 2.04 32 32Sub-Total 31 2635 99.47 2607 2607Wetlands (

7.1.3 Wetland Distribution in South Garo HillsThe South Garo Hills district came into existence on 18th June 1992 after the division of the West Garo Hillsdistrict. The district headquarter is Baghmara. The district is located in the southern part of the state andbounded by West Garo Hills district in the west, East Garo Hills in the north, West Khasi Hills in the East andBangladesh in the South. The district is hilly with difficult terrain. The total geographic area of South Garo Hillsdistrict of Meghalaya is 187083 ha. The wetland area estimated is 3179 ha. Small wetlands, which are lessthan minimum mapable units (MMU), are 7 in the district. The major wetland types are River/Stream.Sr.No.WettcodeTable 8: Area estimates of wetlands in South Garo HillsWetland CategoryNumberofWetlandsTotalWetlandArea% ofwetlandareaOpen WaterPostmonsoonAreaArea in haPremonsoonArea1100 Inland Wetlands - Natural1 1106 River/Stream 127 3172 99.78 3168 3168Sub-Total 127 3172 99.78 3168 3168Wetlands (

7.1.4 Wetland Distribution in West Khasi HillsThe West Khasi Hills district is presently the largest district of Meghalaya. It was carved out from the KhasiHills District on the 28 th October, 1976. It is bounded on the north-west by Kamrup district of Assam, on thenorth-east by Ri-Bhoi district, on the east by East Khasi Hills district, on the south by Bangladesh, on the westby East Garo and South Garo Hills districts. Nongstoin, is the Headquarters of the District. Ranikor,Mawlangkhar, Mawthadraishan, Nongkhnum River Island, Thum Falls, Weinia Falls, Langshiang Falls,Jakrem Hot Spring, Kyllang rock are the major attractions of the region. The total geographic area of WestKhasi Hills district of Meghalaya is 522543 ha. The wetland area estimated is 5920 ha. Small wetlands,which are less than minimum mapable units (MMU), are 10 in the district. Details are given in Table 9. Themajor wetland types are River/Stream and Riverine wetlands.Sr.No.WettcodeTable 9: Area estimates of wetlands in West Khasi HillsWetland CategoryNumberofWetlandsTotalWetlandArea% ofwetlandareaOpen WaterPostmonsoonAreaArea in haPremonsoonArea1100 Inland Wetlands - Natural1 1104 Riverine wetlands 4 679 11.47 427 6282 1106 River/Stream 135 5192 87.70 5067 50671200 Inland Wetlands -Man-made3 1201 Reservoirs/Barrages 8 39 0.66 35 36Sub-Total 147 5910 99.83 5529 5731Wetlands (

7.1.5 Wetland Distribution in Ri BhoiRi Bhoi District was upgraded from Sub Divisional level to a full fledged district on 4th June, 1992. The newdistrict, was carved out from the erstwhile East Khasi Hills. Its headquarter is at Nongpoh, which is about 53Kms from the State Capital, Shillong. It is bounded on the north by Kamrup District and on the East by JaintiaHills and Karbi Anglong District of Assam and on the West by West Khasi Hills district. This district ischaracterized by rugged and irregular land surface. It includes a series of hill ranges which gradually slopedtowards the north and finally joins the Brahmaputra Valley. The important rivers flowing through this regionincludes the Umtrew, Umsiang, Umran and Umiam rivers. The total geographic area of Ri Bhoi district ofMeghalaya is 237005ha. The wetland area estimated is 1945 ha. Small wetlands, which are less thanminimum mapable units (MMU), are 13 in the district. Details are given in Table 10. The major wetland typesare River/Stream and Reservoirs/Barrages.Table 10: Area estimates of wetlands in Ri BhoiArea in haSr.No.WettcodeWetland CategoryNumberofWetlandsTotalWetlandArea% ofwetlandareaOpen WaterPostmonsoonAreaPremonsoonArea1100 Inland Wetlands - Natural1 1106 River/Stream 96 1156 59.43 1222 12221200 Inland Wetlands -Man-made2 1201 Reservoirs/Barrages 10 754 38.77 731 7053 1202 Tanks/Ponds 7 22 1.13 18 21Sub-Total 113 1932 99.33 1971 1948Wetlands (

7.1.7 Wetland Distribution in East Khasi HillsEast Khasi Hills district forms central part of Meghalaya. The headquarter of the district is Shillong which isalso the capital city of State. The district is bounded by Ri-Bhoi district in the north, Bangladesh in the south,Jaintia Hills district in the east and the West Khasi Hills district in the west. Agriculture, horticulture, fisheries,weaving, handicrafts, sericulture and cottage industries makes up the economic scenario of East Khasi Hills.The East Khasi Hills District is mostly hilly with deep gorges and ravines on the southern portion. The mostimportant physiographic features of the district is the Shillong Plateau interspersed with river valley, then fallsharply in the southern portion forming deep gorges and ravine in Mawsynram and Shella-Bholaganjbordering Bangladesh. The total geographic area of East Khasi Hills district of Meghalaya is 285216 ha. Thewetland area estimated is 4796 ha. Small wetlands, which are less than minimum mapable units (MMU), are13 in the district. Details are given in Table 11. The major wetland types are River/Stream, riverine wetlandsand Reservoirs/Barrages.Sr.No.WettcodeTable 11: Area estimates of wetlands in East Khasi HillsWetland CategoryNumberofWetlandsTotalWetlandArea% ofwetlandareaOpen WaterPostmonsoonAreaArea in haPremonsoonArea1100 Inland Wetlands - Natural1 1104 Riverine wetlands 6 593 12.36 409 6432 1106 River/Stream 107 3656 76.23 3758 37581200 Inland Wetlands -Man-made3 1201 Reservoirs/Barrages 5 509 10.61 493 4744 1202 Tanks/Ponds 6 25 0.52 25 23Sub-Total 124 4783 99.73 4685 4898Wetlands (

7.1.7 Wetland Distribution in Jaintia HillsJaintia Hills being a component of the Meghalaya Plateau has its physiographical features almost similar tothat of Khasi Hills. The only difference is that Jaintia Hills has comparably more flat topography with a mildgradient. The Hills gently slope towards Brahmaputra valley of Assam in the North and meet up the gentleplains of Bangladesh in the South. The Marangksih peak on the Eastern plateau of Jaintia Hills standsmajestically at the elevation of 1631 meters from the mean sea level of Karachi and is the highest peak in theentire district. The main elevation of the district ranges between 1050m to 1350m with Jowai which wasestablished in the year 1972 as its Headquarter lies on the central plateau. In general, the whole district is fullof rugged and undulating terrains with the exception of the deep gorges and narrow valleys carved out by therivers. The Jaintia Hills is richly endowed with natural resources. Jaintia Hills have large deposits of coal andrich deposits of other mineral resources. Cement factory, coffee plantations, handloom, fisheries and byproductsof fruit are other means of income for the people of Jaintia. The total geographic area of Jaintia Hillsdistrict of Meghalaya is 379347 ha. The wetland area estimated is 4302 ha. Small wetlands, which are lessthan minimum mapable units (MMU), are 11 in the district. Details are given in Table 12. The major wetlandtypes are River/Stream and Reservoirs/Barrages.Table 12: Area estimates of wetlands in Jaintia HillsArea in haSr.No.WettcodeWetland CategoryNumberofWetlandsTotalWetlandArea% ofwetlandareaOpen WaterPostmonsoonAreaPremonsoonArea1100 Inland Wetlands - Natural1 1106 River/Stream 133 4019 93.42 3186 31851200 Inland Wetlands -Man-made2 1201 Reservoirs/Barrages 1 260 6.04 259 1993 1202 Tanks/Ponds 2 12 0.28 11 12Sub-Total 136 4291 99.74 3456 3396Wetlands (


8.0 MAJOR WETLAND TYPES OF MEGHALAYAMajor wetland types observed in the state are rivers, reservoirs and few lakes. Details are given in Plate-1.Ground truth data was collected for selected wetland sites. The standard proforma was used to record thefield data. Field photographs are also taken to record the water quality (subjective), status of aquaticvegetation and water spread. The location of the features was recorded using GPS. Field photographs andground truth data of different wetland types are shown in Plates 2a,2b and 2c.CBAIRS P6 LISS-III FCCAReservoirBLakesCOx-Bow LakesMNDWI NDPI NDVI (Indices from LISS-IIIPlate - 1: Major wetland types of Meghalaya55

Sr. No.1.Wetland Type :Man-made ReservoirName: Umiam/BarapaniLocation :longitude: 91 0 51’ Elatitude : 25 0 37’ NAquatic Vegetation : AbsentTurbidity : LowDescriptionField photograph2.Wetland Type : RiverName:River Island –NongkhnumLocation :longitude: 91 0 14’ Elatitude : 25 0 25’ NTurbidity : Moderate3.Wetland Type : RiverName: RanikorLocation :longitude: 91 0 14’ Elatitude : 25 0 13’ NTurbidity : Low4.Wetland Type : RiverSantuksiarLocation :longitude: 92 0 12’ Elatitude : 25 0 26’ NTurbidity : LowPlate 2a: Field photographs and ground truth data of different wetland types in Meghalaya56

Sr. No.5.Wetland Type : LakesName: Pamphyrnai lakeLocation :longitude: 91 0 20’ Elatitude : 25 0 32’ NAquatic Vegetation : AbsentTurbidity : LowDescriptionField photograph6.Wetland Type : LakesName: Thadlaskein lakeLocation :longitude: 92 0 10’ Elatitude : 25 0 19’ NAquatic Vegetation : AbsentTurbidity : Moderate7.Wetland Type :Name: BarabilLake-Location:longitude: 89 0 58’ Elatitude : 25 0 45’ NAquatic Vegetation : PresentTurbidity : Low8.Wetland Type :Reservoir/BarragesName: KyredemkhulaiLocation :longitude: 91 0 48’ Elatitude : 25 0 44’ NAquatic Vegetation : AbsentTurbidity : ModeratePlate 2b: Field photographs and ground truth data of different wetland types in Meghalaya57


9.0 IMPORTANT WETLANDS OF MEGHALAYAUmiam lake, Nongkhnum Island and Ranikor riverine area are important wetland sites of Meghalaya.Extensive ground truth data was collected for these selected wetland sites. Wetland maps of 5 km buffer areaand image map of corresponding LISS-III images have been prepared. Details are given in subsequentsections.61

9.1 Umiam LakeUmiam lake, also known as Barapani is located at a distance of 14 Kms from Shillong town on the Shillong-Guwahati road. The place is formed by damming of the Umiam river under the Umiam-Hydro-Electric project.It is one of the places of major tourist attraction in Meghalaya. : Umiam/Barapani ReservoirLocation: 91 o 51’ to 91 o 54’25 o 37’ to 25 o 40’Area: 10.24 Sq KmWetland type: Man-made - ReservoirUmiam reservoir shows change in the wetland waterspreadin premonsoon and post monsoon boundary. Pre-monsoonimage shows marked shrinkage of wetland boundary inparts of the lake boundary. No significant growth of aquaticvegetation seen in the waterbody. The lake shows lowturbidity level.IRS P6 LISS III, November5.Umiam Lake, also known as Barapani is a spot around 15Km from Shillong where a massive hydro-electric dam hasbeen constructed across the Umiam river stream.TheLake is popular for the Water Sport and adventurefacilities that it offers. Kayaking, Water cycling/scootingand boating are a few of the facilities available at theUmiam Lake. The Lake has been developed as a touristspot by the State authorities and the Meghalaya TourismDepartment. The water spread of the reservoir is about10.24 Sq.km. The climate of the area is sub-tropicalmontane characterized by mild summer and cold winters.The annual rainfall in the area is about 2400mm. Theamount of rainfall increases in the southern parts, comingUnder the Mawsynram- Cherrapunji rain belt.IRS P6 LISS III, MarchPlate 3: Umiam lake62

Plate 4: Wetland map - 5 km buffer area of Umiam lake63

9.2 Nongkhnum River IslandNongkhnum Island is the biggest River Island in Meghalaya and the second biggest island in Asia, after MajuliIsland in Assam. Located about 14 Kms from Nongstoin, the district hqs. of West Khasi Hills, it is 20 to 25 sq.kms in area. The area surrounded by the two Rivers, i.e. Phanliang and Namliang forms the NongkhnumIsland. Within the Island, there are big trees and areas of grassland and natural playground. There are plentyof fishing pools, especially near the sandy shore, called Wei-Phanliang. : Nongkhnum River IslandLocation : 91 0 14’ to 91 0 16’25 0 25’ to 25 0 27’Area : 25 Sq. KmsWetland type : Natural- Island formed by riversNongkhnum river island formed by the three rivers is aprominent feature appearing in the satellite image. TheIsland consists of forests, open scrubs and sand depositsalong the river. No significant change observed in thewetland boundary and turbidity in the pre- monsoon andpost-monsoon seasons.IRS P6 LISS III, February 2006NongkhnumIsland5.The climate of the West Khasi Hills is mildly tropical in thenorthern and southern foothills, while in the central uplandzone; the climate is temperate and places at medium altitudein the northern, western and southern parts of the districtexperience sub-tropical climate. Nongkhnum Island is thebiggest River Island in Meghalaya and the second biggestisland in Asia, after Majuli Island in Assam covering an area of25 Sq.Kms located about 14 Kms from Nongstoin, the districthqs. of West Khasi Hills. The Island is formed by thebifurcation of Kynshi River into the Phanliang River and theNamliang River. At the point of divergence, there is a beautifulsandy shore. The Phanliang River forms a beautiful lakeadjacent to the sandy beach. The River then moves along andbefore reaching a deep gorge, forms a pretty fall about 60meters high, called Shadthum Fall. At the bottom of the fall,there is a beautiful pool where a variety of fishes can befound. It then continues its journey and finally reunites with theNamliang River, near a place called Thongrin. There areplenty of fishing pools, especially near the sandy shore, calledWei- Phanliang.IRS P6 LISS III, December 2006NongkhnumIslandPlate 5: Nongkhnum River Island66

Plate 6: Wetland map - 5 km buffer area of Nongkhnum lake67

9.3 RanikorRanikor is an isolated place located around 140 Kms from Shillong in the India- Bangladesh border. It is oneof the largest wild fishing spot left in the state of Meghalaya. This river also offers great birding experience.One can also see tribal anglers using modern as well as traditional means of angling/fishing. It is also a placeof great scenic beauty and tourist attraction.1.Name : RanikorLocation : 91 o 14’ 12.2’’25 o 13 6.22’’2.3.4.Area : Part of riverWetland type : RiverThe river with clear water is the ideal habitat for the fishes.The river flows along the steep hills in Meghalaya and joinsin Bangladesh. The hills along the river stretch is coveredby dense forests. It is very important that proper care istaken for carrying out sustainable fishing practice in theregion.IRS P6 LISS III, December 20065.Located 140 kms from Shillong, Meghalaya,Ranikor is asmall town on the border of India and Bangladesh. It is oneof the last wild fishing spots left in the state of Meghalaya.In the past few years, this place has become famousamongst the local anglers for fish spieces like- Goldenmahseer, Chocolate mahseer, Goonch (Catfish), eels, etc.Fishing area on the river Kynshi at Ranikor is approximately15 to 16 kilometers. The river orginates from a small towncalled Rilang.It is also a place of great scenic beauty, andmakes for an ideal camping spot. The climate of the area issub-tropical montane characterized by mild summer andcold winters. The annual rainfall in the area is about2400mm.IRS P6 LISS III, February 2006Plate 7: Ranikor70

Plate 8: Wetland map - 5 km buffer area of Ranikor71


REFERENCES1. Anon. 2005, NNRMS Standards. A National Standards for EO images, thematic & cartographic maps, GISdatabases and spatial outputs. ISRO:NNRMS: TR:112:2005. A Committee Report: National Natural ResourcesManagement System, Bangalore2. Anon. 1993. Directory of Indian Wetlands, 1993. WWF India, New Delhi and AWB Kuala Limpur, xvi+264pp., 32maps.3. Clark, John R. (1977). Coastal Ecosystem Management, A Wiley Interscience Publication, John Wiley & Sons,New York,.4. Cowardin, L.M., Carter, V., Golet, E.C. and La Roe (1979). Classification of wetlands and deep water habitats.USFWS/085-79/31, Office of the Biological Services, U.S. Fish and Wildlife Service, Washington, D.C.5. Encyclopaedic Directory of Environment (1988). (Ed. By G.R. Chatwal, D.K. Pandey, and K.K. Nanda). Vol. I-IV,Anmol Publications, New Delhi.6. Garg, J.K., Singh, T.S. and Murthy, T.V.R. (1998). Wetlands of India. Project Report: RSAM/sac/resa/pr/01/98,June 1998, 240 p. Space Applications Centre, Ahmedabad,7. Garg J.K. and Patel J. G., 2007. National Wetland Inventory and Assessment, Technical Guidelines andProcedure Manual, Technical Report, SAC/EOAM/AFEG/NWIA/TR/01/2007, June 2007, Space ApplicationsCentre, Ahmedabad,8. Glossary of Geology (1974). (Ed. By Margarate G., Robbert, M. Jr. and Wolf, C.L), American Geological Institute,Washington, D.C..9. Jensen, J.R. (1986). Introductory Digital Image Processing: A Remote Sensing Perspective, Prentice Hall,Englewoods Cliff, NJ.10. Lacaux, J.P., Tourre, Y.M., Vignolles, C., Ndione, J.A. and Lafaye, M. 2007. Classification of ponds from highspatialresolution remote sensing: Application to Rift valley fever epidemics in Senegal. Remote Sensing ofEnvironment, 106, pp. 66-7411. Lillesand, T.M. and Keifer, R.W. 1987. Remote Sensing and Image Interpretation. John Wliey and Sons, NewYork.12. Manorama Yearbook 200713. McGraw - Hill Encyclopaedia of Environmental Science (1974). (Ed. Sybil P. Parkar), McGraw-Hill BookCompany, New York.14. McFeeters, S.K. 1996. The use of Normalised Difference Water Index (NDWI) in the delineation of open waterfeatures. International Journal of remote Sensing, 7, pp. 1425-1432.15. Millennium Ecosystem Assessment. 2005, Ecosystems and Human Well-being: A Framework for Assessment,http://www.MAweb.org16. Mitsch, William J. and Gosselink, James G. (1986). Wetlands, Van Nostrand Reinhold Company, New York.17. Navalgund, R.R., Nayak, S.R., Sudarshana, R., Nagaraja, R. and Ravindran, S. 2002. Proceedings of the ISPRSCommission VII. Symposium on Resource and Environmental Monitoring, IAPRS & SIS, Vol.35, Part-7, NRSA,Hyderabad.18. Patel J.G., Singh T.S., Garg J.K. et al, Wetland Information System, West Bengal,SAC/RSAM/RESA/FLPG/WIS/01/2003, A Technical report: Space Applications Centre, Ahmedabad19. Ramsar Convention (2007). www.ramsar.org20. Reid, George K and Wood, Richard D. (1976). Ecology of Inland Waters and Estuaries. D. Van NostrandCompany, New York.21. SACON, 2004, Inland Wetlands of India : Conservation Atlas. Coimbatore, Salim Ali Centre for Ornithology andNatural History, 2004, ISBN 81-902136-1-X. ,Vedams eBooks (P) Ltd. Vardhaman Charve Plaza IV, Building # 9,K.P Block, Pitampura,22. Singh T.S., Patel J.G., Garg J.K. et al. Loktak Lake Resources Information System (LRIS),SAC/RSAM/RESIPA/FLPG/WIS/02/2003, A Technical report: Space Applications Centre, Ahmedabad23. Statistical hand book of Meghalaya, Directorate of economics and statistics, Govt. of Meghalaya, 200724. Townshend, J.R., and Justice, C.O. 1986. Analysis of dynamics of African vegetation using the Normaliseddifference Vegetation Index. International Journal of Remote Sensing, 7, pp. 1435-1445.25. Tucker, C.J. and Sellers, P.J. 1986. Satellite remote sensing of primary productivity. International Journal ofRemote Sensing, 7, pp. 1395-1416.26. Xu Hanqiu, 2006. Modification of normalised difference water index (NDWI) to enhance open water features inremotely sensed imagery. International Journal of Remote Sensing, 7, pp. 3025-3033.27. http://eastkhasihills.gov.in/district.htm28. http://meghalayaonline.in/profile/districts/East_Garo.asp29. http://westgarohills.gov.in/profile.htm30. http://meghalayaonline.in/profile/districts/West_Khasi.asp31. http://meghalayaonline.in/profile/districts/South_Garo.asp32. http://ribhoi.gov.in/districtprofile_old.htm33. http://jaintia.nic.in/Profile.htm83

Annexure IDefinitions of wetland categories used in the projectFor ease of understanding, definitions of wetland categories and their typical appearance on satellite imagery is givenbelow:WetlandDefinition and descriptiontype code1000 Inland Wetlands1100 Natural1101 Lakes: Larger bodies of standing water occupying distinct basins (Reid et al, 1976). These wetlandsoccur in natural depressions and normally fed by streams/rivers. On satellite images lakes appear indifferent hues of blue interspersed with pink (aquatic vegetation), islands (white if unvegetated, red incase of terrestrial vegetation). Vegetation if scattered make texture rough.1102 Ox-bow lakes/ Cut off meanders: A meandering stream may erode the outside shores of its broadbends, and in time the loops may become cut-off, leaving basins. The resulting shallow crescentshapedlakes are called oxbow lakes (Reid et al, 1976). On the satellite image Ox-bow lakes occurnear the rivers in plain areas. Some part of the lake normally has aquatic vegetation (red/pink incolour) during pre-monsoon season.1103 High Altitude lakes: These lakes occur in the Himalayan region. Landscapes around high lakes arecharacterized by hilly topography. Otherwise they resemble lakes in the plain areas. For keepinguniformity in the delineation of these lakes contour line of 3000 m above msl will be taken asreference and all lakes above this contour line will be classified as high altitude lakes.1104 Riverine Wetlands: Along the major rivers, especially in plains water accumulates leading toformation of marshes and swamp. Swamps are ‘Wetland dominated by trees or shrubs’ (U.S.Definition). In Europe, a forested fen (a peat accumulating wetland that has no significant inflows oroutflows and supports acidophilic mosses, particularly Sphagnum) could be called a swamp. In someareas reed grass - dominated wetlands are also called swamps). (Mitsch and Gosselink, 1986).Marsh: A frequently or continually inundated wetland characterised by emergent herbaceousvegetation adapted to saturated soil conditions. In European terminology a marsh has a mineral soilsubstrate and does not accumulate peat (Mitsch and Gosselink, 1986). Tone is grey blue and textureis smooth.Comment: Using satellite data it is difficult to differentiate between swamp and marsh. Hence, bothhave been clubbed together.1105 Waterlogged: Said of an area in which water stands near, at, or above the land surface, so that theroots of all plants except hydrophytes are drowned and the plants die (Margarate et al, 1974). Floodsor unlined canal seepage and other irrigation network may cause waterlogging. Spectrally, during theperiod when surface water exists, waterlogged areas appear more or less similar to lakes/ponds.However, during dry season large or all parts of such areas dry up and give the appearance ofmud/salt flats (grey bluish).1106 River/stream: Rivers are linear water features of the landscape. Rivers that are wider than themapping unit will be mapped as polygons. Its importance arises from the fact that many stretches ofthe rivers in Indo-Gangetic Plains and peninsular India are declared important national andinternational wetlands (Ex. The river Ganga between Brajghat and Garh Mukteshwar, is a Ramsar site,Ranganthattu on the Cavery river is a bird sanctuary etc.). Wherever, rivers are wide and features likesand bars etc. are visible, they will be mapped.1200 Man-made1201Reservoir: A pond or lake built for the storage of water, usually by the construction of a dam across ariver (Margarate et al, 1974). On RS images, reservoirs have irregular boundary behind a prominentdyke. Wetland boundary in case of reservoir incorporates water, aquatic vegetation and footprint ofwater as well. In the accompanying images aquatic vegetation in the reservoir is seen in bright pinktone. Tone is dark blue in deep reservoirs while it is ink blue in case of shallow reservoirs or reservoirswith high silt load. These will be annotated as Reservoirs/Dam.Barrage: Dykes are constructed in the plain areas over rivers for creating Irrigation/water facilities.Such water storage areas develop into wetlands (Harike Barrage on Satluj – a Ramsar site, Okhlabarrage on the Yamuna etc. – a bird sanctuary). Water appears in dark blue tone with a smoothtexture. Aquatic vegetation appears in pink colour, which is scattered, or contiguous depending on thedensity. Reservoirs formed by barrages will be annotated as reservoir/barrage.85

1202 Tanks/Ponds: A term used in Ceylon and the drier parts of Peninsular India for an artificial pond, poolor lake formed by building a mud wall across the valley of a small stream to retain the monsoon(Margarate et al, 1974). Ponds Generally, suggest a small, quiet body of standing water, usuallyshallow enough to permit the growth of rooted plants from one shore to another (Reid et al, 1976).Tanks appear in light blue colour showing bottom reflectance.In this category Industrial ponds/mining pools mainly comprising Abandoned Quarries are alsoincluded (Quarry is defined as "An open or surface working or excavation for the extraction of stone,ore, coal, gravel or minerals." In such pits water accumulate (McGraw Hill Encyclopaedia ofEnvironmental Sciences, 1974), Ash pond/Cooling pond (The water body created for dischargingeffluents in industry, especially in thermal power plants (Encyclopaedic Directory of Environment,1988) and Cooling pond: An artificial lake used for the natural cooling of condenser-cooling waterserving a conventional power station (Encyclopaedic Directory of Environment, 1988). These pondscan be of any shape and size. Texture is rough and tonal appearance light (quarry) to blue shade(cooling pond).1203 Waterlogged : Man-made activities like canals cause waterlogging in adjacent areas due to seepageespecially when canals are unlined. Such areas can be identified on the images along canal network.Tonal appearance is in various hues of blue. Sometimes, such waterlogged areas dry up and leavewhite scars on the land. Texture is smooth.1204 Salt pans: Inland salt pans in India occur in Rajasthan (Sambhar lake). These are shallow rectangularman-made depressions in which saline water is accumulated for drying in the sun for making salt.2000 Coastal Wetlands2100 Natural2101 Lagoons/Backwaters: Such coastal bodies of water, partly separated from the sea by barrierbeaches or bass of marine origin, are more properly termed lagoons. As a rule, lagoons are elongateand lie parallel to the shoreline. They are usually characteristic of, but not restricted to, shores ofemergence. Lagoons are generally shallower and more saline than typical estuaries (Reid et al, 1976).Backwater: A creek, arm of the sea or series of connected lagoons, usually parallel to the coast,separated from the sea by a narrow strip of land but communicating with it through barred outlets(Margarate et al, 1974).2102 Creek: A notable physiographic feature of salt marshes, especially low marshes. These creeksdevelop as do rivers "with minor irregularities sooner or later causing the water to be deflected intodefinite channels" (Mitsch and Gosselink, 1986). Creeks will be delineated, however, their area willnot be estimated.2103 Sand/Beach: Beach is an unvegetated part of the shoreline formed of loose material, usually sandthat extends from the upper berm (a ridge or ridges on the backshore of the beach, formed by thedeposit of material by wave action, that marks the upper limit of ordinary high tides and wave wash tolow water mark(Clark,1977).Beach comprising rocky material is called rocky beach.2104 Intertidal mudflats: Most unvegetated areas that are alternately exposed and inundated by thefalling and rising of the tide. They may be mudflats or sand flats depending on the coarseness of thematerial of which they are made (Clark, 1977).2105 Salt Marsh: Natural or semi-natural halophytic grassland and dwarf brushwood on the alluvialsediments bordering saline water bodies whose water level fluctuates either tidally or non- tidally(Mitsch and Gosselink, 1986). Salt marshes look in grey blue shade when wet.2106 Mangroves: The mangrove swamp is an association of halophytic trees, shrubs, and other plantsgrowing in brackish to saline tidal waters of tropical and sub-tropical coastlines (Mitsch and Gosselink,1986). On the satellite images mangroves occur in red colour if in contiguous patch. When mangroveassociations are scattered or are degraded then instead of red colour, brick red colour may be seen.2107 Coral reefs: Consolidated living colonies of microscopic organisms found in warm tropical waters. Theterm coral reef, or organic reef is applied to the rock- like reefs built-up of living things, principallycorals. They consist of accumulations of calcareous deposits of corals and corraline algae with theintervening space connected with sand, which consists largely of shells of foraminefera. Present reefsare living associations growing on this accumulation of past (Clark, 1977). Reefs appear in light blueshade.2200 Man-made2201 Salt pans: An undrained usually small and shallow rectangular, man-made depression or hollow inwhich saline water accumulates and evaporates leaving a salt deposit (Margarate et al, 1974). Saltpans are square or rectangular in shape. When water is there appearance is blue while salt is formedtone is white.2202 Aquaculture ponds: Aquaculture is defined as "The breeding and rearing of fresh-water or marinefish in captivity. Fish farming or ranching". The water bodies used for the above are called aquacultureponds (Encyclopaedic Directory of Environment, 1988). Aquaculture ponds are geometrical in shapeusually square or rectangular. Tone is blue.86

Annexure – IIDetails of District information followed in the atlasSource : Survey of India (Surveyed in 2004 and published in 2005)87

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