I 'm also interested in calculating carbon for my forests. You can use ENVI to calculate the carbon for the forest?

ENVI does not have any tools specifically designed to calculate the amount of carbon in the forest (or the change in the amount of carbon). But you may be able to find published studies that relate the amount of carbon in the type of forest in your area of interest to parameters that you can derive from remotely sensed imagery. Then ENVI would most likely be able to calculate those parameters from your imagery. It could be that further research will be necessary to determine the relationship between the amount of carbon in the forest in your area of interest and parameters that you can derive from remotely sensed imagery. - Peg

I read envi Help "Using ENVI > Vegetation Indices > Vegetation Indices". Can Landsat image calculate for "ENVI provides 27 vegetation indices"? I want to know who knew the index calculated with the formula so that it made ??a star of Envi. I remember having read somewhere in the Envi can be calculated based on carbon and chlorophyll... I'll try and make the discussion in this forum.

Right. Some of ENVI's vegetation indices would be the types of parameters that you can derive for your images, and for which you might be able to establish a relationship with the amount of carbon in the forest. But the indices themselves don't return the amount of carbon or chlorophyll directly. With Landsat data, the only indices you will be able to calculate are the NDVI and the SRI. These are both indices for broadband greenness. To calculate the other indices, you need hyperspectral imagery. - Peg

Thanks you very much. I try it. Can I use Spot5 image sattellite to calculate all Vegetation Indices in Envi?

No, SPOT 5 is also only multispectral, and it has less bands than Landsat, within the same wavelength range. You need to have hyperspectral data, which has hundreds of very narrow contiguous bands, to calculate most of the vegetation indices in ENVI. - Peg