Rice and mangrove monitoring in the Mekong Delta, Vietnam using remote sensing data

Transcription

1 International Workshop on Air Quality in Asia Inventory, Modeling and Climate Impacts of Greenhouse Gas emissions (GHG s) and Aerosols; Remote sensing applications and Integrated Technologies Hanoi, June th, 2014 Rice and mangrove monitoring in the Mekong Delta, Vietnam using remote sensing data Lam Dao Nguyen VN Southern Satellite Technology Application Center VNSC VAST Pham Bach Viet Faculty of Geography USSH VNU HCM Thuy Le Toan CESBIO, France Hoang Phi Phung VN Southern Satellite Technology Application Center VNSC VAST Pham Thi Mai Thy GIS and Remote Sensing Research Center HCMIRG VAST

2 Contents 1. Introduction 2. Rice crop monitoring 3. Mangrove forest monitoring 4. Conclusions

3 Introduction Research projects: WISDOM: Water related information system for the MD, Vietnam RICEMAN: Rice & Mangrove monitoring in Southern Vietnam Planet Action: Impacts of climate change and human activities on the environment in the MD, Vietnam Utilization of SAR data for rice crop monitoring National Foundation for Science & Technology Development Estimation the mangrove forest biomass Change detection of Mekong river bank, coastline & LCLU

4 Introduction Mekong Delta, Vietnam (Source: GSO, 2012): Area: 40,500 Km 2 (1/8) Population: 17.4 M (1/5) MD accounts for more than half (24.3 / 43.7 Mt) of the country s rice production (>1/2) Radar data Why Satellite RS? Synoptic measurements on large areas; Near real time; Low cost; etc. Optical data

5 Introduction Source: Parry, M.L. et al., 2007 The Mekong Delta, South of Vietnam is one of the most affected regions in the world by global warming e.g. ocean warming, rise in sea level, typhoons, storm surges; These are expressed in intensive flooding at coastal zones and inland, salinity intrusion, coastal erosion, and degradation of biodiversity. Studies need to be carried out to quantify the changes observed by satellites in land use / land cover, in coastline, riverbank, in flood extent and duration, and in cultural practices, etc.

6 Introduction Long Xuyen Quadrilateral Plain of Reeds HCM City Ca Mau Peninsula ENVISAT ASAR MODIS

7 LULC Change Landsat

8 Methane emission from rice fields Source: Thuy Le Toan, CESBIO

9 Monitoring straw burning from MODIS In dry season 2010 Source: Pham Duy Tien, AGU

10 Monitoring straw burning from MODIS In dry season ha with 7 ton straw = emission of 9.1 ton CO 2, 798 kg CO, etc. Source: Pham Duy Tien, AGU

11 Rice backscatter analysis HH/VV (db) Dec 06 Feb 07 Apr 07 Jun 07 Aug 07 Oct 07 Dec 07 HH/VV (db) Aug 10 Oct 10 Dec 10 Feb 11 Apr 11 Jun 11 Temporal variation of average polarization ratio HH/VV of ASAR APP (left) and TSX SM (right) for sample rice fields in Cho Moi

12 Rice backscatter analysis 12.0 Hệ số tán xạ ngược (db) Cây hàng năm 1 Cây hàng năm 2 Nông thôn 1 Nông thôn 2 Lúa 1 Lúa 2 Sông 1 Sông 2 Đô thị 1 Đô thị /12/ /01/ /02/ /03/2011 Thời gian HH&VV ratio of land use / land cover classes

13 Rice mapping (using ASAR APP) Site: An Giang WS 2007 crop WS 2008 crop WS 2011 crop 13 SA 2007 crop AW 2007 crop AW 2010 crop

14 Rice mapping (using ASAR APP & CSK PP) AW 2007 crop from ASAR APP AW 2010 crop from ASAR APP AW 2013 crop from CSK PP

15 Rice cropping system & yield estimation (using ASAR APP 2007) Estimated rice yield of SA 2007 crop at Cho Moi district, An Giang province

16 Rice yield estimation (using CSK PP 2013) Estimated rice yield of AW 2013 crop at Chau Thanh & Thoai Son district, An Giang province

17 Mangrove monitoring Site: Ca Mau Problems: The issue of coastal land conversion for commercial shrimp farming Typical land cover is mangrove, which has changed by human activities.

18 Mangrove monitoring Landsat MSS, 03 Jan 1973 Land cover map, 1973 SPOT, 6 April 2000 Land cover map, 2000 Non Forest Forest Built-up Cloud Aquaculture Forest Built-up Annual plants Cloud : this area was suffered a mass destruction by defoliants From satellite images => rate of mangrove forest change SPOT, 10 Mar 2008 Land cover map, 2008

19 Mangrove monitoring Sites: Soc Trang, Bac Lieu, Ca Mau Mangrove change from satellite images w/o mangroves Mangroves unchanged Mangroves changed to others Others to mangoves

20 Ongoing research works APPLIED RESEARCH ON ACTIVE MICROWAVE REMOTE SENSING AND STATISTICAL MODEL FOR ESTIMATING THE MANGROVE FOREST BIOMASS (12/ /2014, NAFOSTED NATIONAL LEVEL). Distinguishing some objects of mangroves from radar data Analyzing radar scattering characteristics of mangroves correlating with forest biomass. Developing algorithms for classification, mapping and calculating biomass by active microwave remote sensing.

21 Location map of sampling sites

22 No. of ground data: 120

23 23

24 Classified image of PLR 23/11/2010

25 Ongoing research works INTEGRATED SYSTEM OF REMOTE SENSING, GIS AND MATHEMATICAL MODEL FOR ASSESSING CLIMATE CHANGE IN SOUTHERN VIETNAM ( , MOST NATIONAL LEVEL) Identifying the changes of sea level Applying mathematical models and GIS tools to quantify the changes caused by human activities (land cover/land use, agricultural, irrigation, forest cover, etc.) and the changes related to a number of climatic factors (temperature, humidity, evaporation, precipitation, etc.), and natural hazards (erosion, flooding, drought, salinity, etc.);

26 Ongoing research works UTILISATION OF SATELLITE IMAGERY (VNREDSAT 1 AND EQUIVALENT) FOR MONITORING AGRICULTURAL LAND COVER/LAND USE OF THE MEKONG DELTA, VIETNAM ( , MOST NATIONAL LEVEL) Using VNREDSat 1 satellite data for updating and assessing the changes of the main land use types in the Mekong Delta, Vietnam, i.e. rice, orchard trees, forest and aquacultural land.

27 ?/year Ongoing research works RICE CROP MONITORING IN THE MEKONG DELTA, VIETNAM ( , SAFE PROJECT) ON GOING PROJECT: AsiaRICE?/year GIS & Remote Sensing Research Center GIRS/HCMIRG/VAST Japan 1 time/year Planting: May Jun Harvesting : Sep Oct?/year GEOGLAM?/year 2/year?/year?/year GEO Global Agricultural Monitoring 1/year 2 3/year?/year Asian Rice Crop Estimation & Monitoring?/year 3/year 2/year

28 Conclusions Remote sensing technique provide a useful tool and satellite data gives an objective view at large scale. The projects have been carrying out in the MD, Vietnam in order to monitor dynamic changes of LULC and others using time series of EO data for their management needs. Remote sensing applications using coarse and medium resolution satellite data for monitoring rice and mangrove in the MD, Vietnam yields preliminary reasonable results.

29