1. USGS contribution to assessing mangrove conditions using a multidisciplinary approach
Elitsa Peneva-Reed
24 October, 2017

2. USGS Wetlands Mapping USGS wide array of wetlands topics
Coastal processes
Coastal ecosystems
Conservation
Local, Regional, National, and International in scope
USGS wetlands projects
LCMAP (annual time-series)
Dynamic surface water extent ECV
Coastal National Elevation Database Applications Project (CoNED) – Wetland Lidar Research
Mangrove mapping

3. The Big Picture
Mangroves forests are an important ecosystem providing benefits for disaster protection, biodiversity and climate change mitigation
However, in many cases there is not a good knowledge of area and structure change of mangroves areas.
The developed methodology could be applied to other mangrove areas to study temporal and spatial dynamics of area, structure, carbon stock and carbon sequestration.

4. Mangrove Monitoring and Carbon Assessment Project
USGS Biological Carbon Sequestration Assessment Program
OVERVIEW
The project integrates remote sensing and field data observations to monitor and estimate the above ground biomass and carbon stored in mangrove ecosystems and to create a baseline for future carbon sequestration estimates and forecasting in J.N. “Ding” Darling National Wildlife Refuge, Florida, USA and Pohnpei, Federated States of Micronesia.
METHODOLOGY
Annual Landsat Mapping and Assessment
Field work to assess in situ biophysical characteristics
Allometry to assess carbon stocks
PRELIMINARY RESULTS
Based on the Time Series Analysis
Based on the Field Data Collected
Carbon Estimates

5. Study Areas Pohnpei, Federated States of Micronesia
Ding Darling National Wildlife Refuge, Florida, USA

6. Annual Landsat Mangrove Mapping and Assessment
Continuous Change Detection and
Classification (CCDC)
1985
2017
Landsat Time Series
(WRS Path Row 16/42).
CCDC uses all available
Landsat data on a per pixel
basis.
Over 1,000 Landsat images
were used in this analysis.
Ding Darling National Wildlife Refuge, Florida, USA
Citation: Zhu, Z., et al., Continuous monitoring of forest disturbance using all available Landsat imagery. Remote Sensing of Environment.122:75-91

7. Preliminary Results In August 2004, a Category 4 hurricane
Change Detection in the Mangrove Ecosystem of J.N. "Ding" Darling National Wildlife
Refuge, Florida
( )
Year
Total Mangrove
Area
(ha)
Change in
Mangrove Area
1985
1094.9
0.0
1986
1987
0.6
1988
1095.6
-1.2
1989
1094.4
0.3
1990
1094.7
1.4
1991
1096.1
0.5
1992
1096.7
-0.2
1993
1096.5
-0.9
1994
0.1
1995
1095.7
-0.1
1996
1997
1998
1095.5
0.4
1999
1095.8
0.2
2000
1096.0
-1.8
2001
1094.2
0.8
2002
1095.0
2003
1095.2
2004
1095.4
-45.8
2005
1049.6
2006
1050.9
-2.8
2007
1048.1
4.7
2008
1052.8
1.2
2009
1054.0
1.6
2010
1055.6
10.4
2011
1066.0
2.1
2012
1068.0
1.0
2013
1069.0
2014
1068.9
2015
1069.3
-1.3
2016
1067.9
-0.8
2017
1067.1 NA
In August 2004, a Category 4 hurricane
Charley slammed ashore a few miles
north of Ding Darling NWR.

8. CCDC identified loss of forest due to hurricane Charley of 2004
as seen in year 2005.
During field work our team identified dead trees as well as regrowth in these areas.

9. Field work to assess in situ biophysical characteristics
Sampling Design
Using results reported in Kaufmann and
colleagues (2014) with allowable error of 0.2
it was determined that 23 transects should be
sampled.
Each transect consists of 5 consecutive plots
with distance between them of 25 meters set
perpendicular to the mangrove water
ecotone edge.
Each transects starts 15 meters
away from the mangrove water ecotone
border.
Adapted from:
Kauffman, J.B., and D.C. Donato Protocols for the measurement, monitoring and reporting of structure, biomass and carbon stocks in mangrove forests In. Working Paper 86, CIFOR

10. Field Data ( 23 Transects established)
Smith and Whelan (2006) developed allometric equations that were used to convert the biophysical data into above ground biomass for 3 primary species that occur in DD NWR, primarily based on the relationship of DBH to carbon stock.
Preliminary Results

11. Carbon Estimates Preliminary Results 1. Biomass of plots
Smith and Whelan (2006) developed allometric equations that were used to convert the biophysical data into above ground biomass for 3 primary species that occur in DD NWR, primarily based on the relationship of DBH to carbon stock.
Carbon Estimates
Preliminary Results
1. Diameter at breast height (DBH)
2. Allometric equations (from Smith and Whelan, 2006)
1. Biomass of plots
2. Proportion of mangrove biomass to carbon (~ 0.465)
3. Area of plots
4. Carbon density of plots ( MgC/ha)
5. Hectares of mangroves in DD NWR in 2016 (~1067)
Total Carbon stored as Above Ground Biomass in DD NWR
(52,998 MgC)

12. Total mangroves on the island = 5000 ha.
Pohnpei coordinates: ° N, ° E
Why Pohnpei, FSM:
FSM has a close relationship with the USA - DOI Office of Insular Affairs manages the Compact with FSM
After 2nd world war the United States took over the island as a United Nation's Trust Territory.　 And finally in 1979, a federation was established between Pohnpei and the neighboring Trust Territory islands of Yap, Chuuk and Kosrae. These four islands became the Federated States of Micronesia, and in 1986 gained official independence when the US ratified the Compact of Free Association treaty.

13. High resolution map of the mangrove distribution

14. The total mapped area of Mangrove forest is 5,723 hectares.
Landsat and SPOT satellites lack the detail and cloud-free coverage required for detailed mangrove mapping
We used high resolution WorldView 2 (WV2) and Quickbird Satellite Imagery
The results of this study are based on the accuracy assessment derived from the
stratified random sample of 500 reference points. The overall accuracy of the
mangrove map for Pohnpei was very high at 98.9 ± 1%.
The total mapped area of Mangrove forest is 5,723 hectares.

15. Field work to assess in situ biophysical characteristics
Sampling Design
𝐌𝐢𝐧𝐢𝐦𝐮𝐦 𝐧𝐮𝐦𝐛𝐞𝐫 𝐨𝐟 𝐬𝐚𝐦𝐩𝐥𝐞𝐬 𝐧 = 𝒕∗𝒔 𝑬 𝟐
Using preliminary results (carbon estimates
and the standard deviation) from our study in
Ding Darling NWR in Florida with allowable
error of 0.2 it was determined that
39 sample transects will have to be sampled.
A transect consists of consecutive points
with distance between them of 150 meters.
Distance between the rows and columns
is set at 1.5 km.
If the distance between two points is longer
than 450 meters (three cells) than that is
considered to be separate transect.
There are 61 transects where some transects
consist of 1 and some of 15 plots per
transect.
Adapted from:
Kauffman, J.B., and D.C. Donato Protocols for the measurement, monitoring and reporting of structure, biomass and carbon stocks in mangrove forests In. Working Paper 86, CIFOR
Donato, D. and Mackenzie, Filed Protocol for Monitoring Ecological Function and Sea-Level Rise Impacts in Palau Mangroves

17. It takes a village to finish a transect

18. Capacity-building Workshop Above Ground Biomass Estimation
7-11 August, 2017
Pohnpei, Federated States of Micronesia

19. Future Research Accuracy Assessment of the Remote Sensing Results.
Apply the developed methodology to other mangroves areas.