![Observed Results VWC ~ NDWI NDWI has a good correlation to VWC, while band 5 has bigger R value VWC information maybe can be estimated by NDWI 5, for vwc in [0,4]](https://image.slidesharecdn.com/monitoring-vegetation-water-content-by-using-optical-vegetation-index-and-microwave-vegetation-index-field-experiments-and-applications-110727120728-phpapp02/85/MONITORING-VEGETATION-WATER-CONTENT-BY-USING-OPTICAL-VEGETATION-INDEX-AND-MICROWAVE-VEGETATION-INDEX-FIELD-EXPERIMENTS-AND-APPLICATIONS-ppt-11-320.jpg)
MONITORING VEGETATION WATER CONTENT BY USING OPTICAL VEGETATION INDEX AND MICROWAVE VEGETATION INDEX FIELD EXPERIMENTS AND APPLICATIONS.ppt
- 1. Monitoring Vegetation Water Content by Using Optical Vegetation Index and Microwave Vegetation Index: Field Experiment and Application Hui Lu ( Tsinghua University, China ) Toshio Koike & Hiroyuki Tsutsui ( The University of Tokyo ) Hedeyuki Fujii ( JAXA )
- 2. Outline Background and motivation Microwave vegetation index Field Experiment Setting and instruments Observed Results Application Mongolia site Remark
- 3. Background Global vegetation information is closely related to Food productivity, famine, …… Environment, ecological system, …. In land surface modeling and remote sensing retrieval, vegetation is A key variable of land surface remote sensing Soil moisture, soil temperature, vegetation water content A key parameter in GCM, hydrology and land surface scheme LAI, fPAR, ET, precipitation interception A key parameter in terrestrial ecosystem model Carbon cycle
- 4. Motivation Vegetation parameters observed by satellites: VIS/IR: fractional coverage, NDVI, LAI, NDWI, EVI MW: Vegetation water content (VWC), Microwave vegetation index (MVI) MW RS has daily global coverage and deeper penetration depth Complement vegetation information to VIS/IR What the relationship between these parameters? Accurate VWC is useful in Improving soil moisture retrieval algorithm Improving LDAS
- 5. VWC, MVI, NDVI, NDWI Microwave vegetation index by Shi NDVI: VIS (620 - 670nm) & NIR (841 - 876 nm) NDWI:SWIR in band 5 (1230-1250 nm) or band 6 (1628-1652 nm)
- 6. Field Experiment --Instruments and setting Brightness temperature observed by Ground Based Microwave Radiometer, at 6.925, 10.65, 18.7, 23.8, 36.5, 89 GHz VIS/IR reflectance measured by ASD FieldSpec Pro in a spectral range of 350nm – 2500nm
- 7. Experiment design 1 2 3
- 8. Experiment design Observing winter wheat One kind of main crops VWC is not so big, C-band could penetrate. Winter wheat development VWC was measured by sampling
- 9. Vegetation 01-16 01-19 01-24 02-07 11-29 12-08 12-13 12-20
- 10. Observed Results VWC ~ NDVI NDVI shows a poor correlation to the VWC, with an R-square less than 0.2. It is not good to estimate VWC from NDVI observation!
- 11. Observed Results VWC ~ NDWI NDWI has a good correlation to VWC, while band 5 has bigger R value VWC information maybe can be estimated by NDWI 5, for vwc in [0,4]
- 12. Observed Results VWC ~ MWI VWC = linear regression function of MVI High R for X-C band
- 13. Application Domain AMPEX Mongolia; Relative homogenous VWC survey at 2003 Jul and Aug; 160*120km;
- 14. Application: VWC retrieved from JAXA algorithm Vs. in situ VWC provided by JAXA algorithm is comparable to the in situ observed VWC Using as reference data to check the performance of MVI-based method
- 15. Results: VWC from MVI-based method A3 H7 MVI(10,6) MVI (18,10) High R for X-C band
- 16. Remark Field experiment which observing winter wheat development by using microwave radiometer and VIS/IF spectroradiometer simultaneously. Comparing to in situ observed VWC NDVI show poor correlation NDWI show good correlation MVI show strong correlation MVI-based linear equation could provide VWC information, but the absolute values should be scaled Can be used to monitor the vegetation temporal variation The coefficient of linear equation should be related to (vfc, vegetation type) Future work: Quantify the coefficient by each vegetation type (LSM classification, or real type) Test for more observation sites (US site, MDB site, China)
- 17. Thank you for your attention!
Editor's Notes
- #9: E Emergence 0 29-Nov-06 DR Floral initiation (double ridge) 35 3-Jan-07 TS Terminal spikelet 60 28-Jan-07 First node 80 17-Feb-07 HD Heading 120 29-Mar-07 A Anthesis 130 8-Apr-07 PM Physiological maturity 170 18-May-07