The document summarizes a study that analyzed changes in wetlands and their ecosystem services in the cities of Kolkata and Nagpur, India between 2000 and 2013 using satellite imagery and field surveys. It found significant losses of wetland areas in both cities due to urbanization and changes in land use. Though many wetlands still provide a variety of important ecosystem services, conservation policies are needed to protect the remaining wetlands from further losses.

1. Wetland spatio-temporal change analysis and
ecosystem services in two urbanizing cities
Research team: Priyanie Amerasinghe,
Matthew McCartney, Kiran Apsunde and
Kanika Mehra
Bahir Dar, Ethiopia, 23-29 September 2015
Daniel Van Rooijen
International Water Management Institute

2. Contents
• Introduction
• Methods
• Case study city characteristics

3. Introduction: Wetlands in India
• A wealth of ecosystem service benefits
• Inadequate attention in the national water sector
agenda
• Urbanization, population increase, land-use
changes have impacted
• Emphasis has been on ecologic and limnologic
studies
• Hydrological, landscape and wetland spatio-
temporal change analysis studies are sparse

4. Methods
• Two cities (2014):
Kolkata, West Bengal
Nagpur, Maharashtra
• Landsat 7 and 8 satellite images 2000 and 2013
(November/December – post monsoon/winter)
• Supervised Image classification and Modified
Normal Difference Water Index (MNDWI);
• TEEB’s approach (The Economics of Ecosystems
and Biodiversity) to assess ESS – A total of 27 ESS
were selected, based on observations and surveys.
• 4 wetlands were investigated to validate the ESS
and wetland dependence by poor communities

5. Photo:DavidBrazier/IWMIPhoto:TomvanCakenberghe/IWMI
Kolkata Nagpur
City type Metropolitan City Metropolitan City
Population KMC- 4.49 million
KMDA-14.77 million
NMC- 2.41 million
Population density 24,000 persons/ sq. km 11,000 persons/ sq. km
Area KMC-185 sq. km
KMDA-1886 sq. km
NMC- 217 sq. km
NMA- 3780 sq. km
Main industries IT industry Mining and agriculture (Orange
City of India)
Population Growth
rate
1.73% n.a.
Climate Annual rainfall:1,582 mm
Annual mean temperature
250 C
Annual rainfall: 1,205 mm
Annual temperature 20-330 C
City characteristics

6. Location of study sites
0 3 6 9 121.5
Kilometers
Kolkata
Area: 87,500 ha
Nagpur
Area: 92,500 ha

7. CLICK TO EDIT MASTER TITLE STYLE
Mapping Natural and Built Infrastructure
• TCWI = Tasselled Cap Wetness Index
• MNDWI = Modified Normalized Difference
Water Index
• NDVI = Normalized difference Vegetation
Index
• DN = Digital Number
MNDWI was found to be the most suitable index.
The water bodies therefore were extracted using
MNDWI
Field Validation of
mapped features
Post Validation
Changes
Final Maps
Landsat 7 -2000
Landsat 8 - 2013
Mapped & Classified
2000 & 2013
Field Validation
Change Analysis at City and
Watershed Level

8. Wetland Selection and Field Surveys (HH & FGDs)
Ecosystem Services
Check-listing / Scoring
Wetland Selection based
on ES Score & Community
dependence
Questionnaire Preparation,
Validation, Revision and
Field Surveys.
For each of the ES identified, a score of 1 was given and summed-up to give a
final score for the wetland.

9. Legend
Hoogli River
KMC_Boundary
Built-up
Water Bodies
Open Spaces/ Wastelands
Orchards/Trees
Agriculture/Shrubs
Map_Area
± 0 3 6 9 121.5
Kilometers
0 3 6 9 121.5
Kilometers
November 2000 November 2013
Land Cover Changes: 2000 and 2013 – Kolkata

10. Results from
Kolkata 1/2
• Size class of 0.36 ha and above were mapped (over
3,300 wetlands)
• Built up areas (6%) and waste/open lands increased
(1%)
• Water bodies (3%), orchards and trees (5%)
Agriculture and shrub lands (10%) decreased
• 4 types of wetlands tanks, aquaculture/paddy rice,
riverine marsh/lagoons and treatment units (10,645
ha)
• Area-wise tanks constituted 12%, only 1.2% (127
ha) were natural. Rest was the EKW (East Kolkata
Wetland)

11. Results from Kolkata 2/2
• 50% reduction in wetland area over a 12 year
period
• 37 wetlands were scored for ES. 30 in urban and
7 periurban
• Number of reported Ecosystem Services (ES)
varied between 4-20 per wetland
• High number of ES provided by a majority of
wetlands (75% fell within 15-17 range)

12. Distribution of ES (%)
1 Bathing and washing
2 Recreation
3 Religious activities
4 Medicinal plants/food
5 Fishing
6 Firewood
7 Construction Material
8 Agriculture
0
20
40
60
80
100
1 2 3 4 5 6 7 8
Urban Wetlands Peri-Urban Wetlands

13. 0 4 8 12 162
Kilometers
±Land Cover in Nagpur City
Legend
Stream Network
Watershed BOundary
NMC_Boundary
Subwatersheds
GRIDCODE
Built-up
Water Bodies
Vegetation/Forest
Agriculture/Scrubs
Open/Fallow
Sand Mine
Ash Pond
River Bed
Year 2000
Year 2013

14. Results – Nagpur 1/2
• Size class of 0.36 ha and above were mapped
(182 wetlands)
• Built-up area (5%) agriculture/shrub land area
(3%) increased
• Marginal changes in water bodies
• Forest area (5%) open fallow land (3%)
decreased
• 4 types of wetlands: tanks, reservoirs, water
logged areas in quarries and treatment plants
(844 ha)

15. Results - Nagpur 2/2
• 90% of wetland area were tanks and reservoirs
• 0.4% were classified as natural
• Loss of natural tanks (70%) was significant (was
obscured by water in quarries)
• ES scores varied from 15-23, and the
distribution was very similar that found in Kolkata

16. Conclusions
• Wetlands in Kolkata and Nagpur support a rich
diversity of ES
• No other studies available on wetland spatio–
temporal changes that can evidence wetland losses
• Wetland conservation plan is necessary (Wetland
conservation policy drafted but not implemented)
• Engagement of decision makers and users is
important to develop policies that are relevant to
wetland conservation.

17. Thank you
• WLE program for funding
• Daniel van Rooijen (IWMI - Ethiopia)
• Anuradha Adikari and Aruna Jyoti (IWMI-
Hyderabad)
• Stakeholders in Kolkata and Nagpur
• South Asia Forum for Environment, Kolkata
• Centre for Rural Research and Community
Development, Nagpur
For more info contact Dr. Amerasinghe (p.amerasinghe@cigar.org)