Nowadays there are several methods to measure LAI in Eucalyptus forests, part of them are destructive methods and too expensive and hard to carry on in large scale. This kind of measurement is important to be used in ecophysiological modeling process in order to estimate the forest productivity. Therefore, if there are simple and suitable methods to be used in large scale, forestry companies could improve theirs capacity to foresee future productivities on base corrent LAI measurement.
I think that the best method to estimate LAI, is the hemispherical photograph with an eye-fish lense. You just need a camera and the lense and the program. There are some of them in market. I hope this information could be useful. In the meantime I would look for the complete information about the computer program. Cheers.
Hello Mr. Barradas. I would like to thank you for your information which is suitable for my work. I also found the software "hemisfer", that is used to deal with the data from the eye-fish method. Regards, Sergio Ricardo
Also you can find an equipment from BioScience (CI - 110 / 120) that measure the gap fraction and estimates directly the leaf area. Other softwares you can use to estimate gap fraction from hemispherical pictures are Gap Light Analyzer (GLA) and CAN-EYE.
Mr. Baldissera, thanks for your comments and suggestions. I guess this method sounds to be efficient to be used in commercial eucalypts stands. Regards, Sergio Ricardo.
I do not know, but I have my doubts with this instruments company. Some time ago I purchased to them a system for measuring photosynthesis and truly was a waste of money because the system never worked properly despite being sent to the factory for repair / calibration. On the other hand, you also can estimate gap fraction and many other measures as sunfleck distribution and PAR with the system I recommended before that I think it is not as expensive as the other one.
Hello Mr. Barradas. I must agree with you, because I have the opportunity to deal with similar equipment used to estimate gap fraction and the results were not good. In fact, this methodology must be improved in order to supply best results. Regards, Sergio Ricardo.
There are lots of papers published by Macfarlane on estimating LAI of Eucalypt forest with cover photography, a more simple, cheap and fast method compared with hemispherical photo. No dedicated softare required. See link below
http://www.sciencedirect.com/science/article/pii/S0168192306003376
This last Macfarlane et al photography method looks very interesting and maybe there is already a computer program to make the calculations maybe it is possible to ask for it.
I have found that an LAI2000 can be used in pine forest so long as the calibration model takes spacing into account. See my paper in Agric. & For. Met. In that paper we compared an LAI2000 with 11 samples to single hemispherical images analysed with Gap Light Analyzer, and found the LAI2000 to be a bit better. I have since used CANEYE to analyze the same images and it produced higher correlations with actual LAIs than GLA did, but not quite as high as those between the LAI2000 and actual LAIs.
Hemispherical images can be used so long as you have a calibration data set from biomass sampling with which to calibrate your method. Use at least 6 images per stand, and use CANEYE with thresholding on the visible sky. You will find that the thresholding slider reaches a point beyond which no further sky is found, and in this way the method can be reasonably user-independent. CANEYE analyses all six images at once and provides some excellent statistical summaries.
Article Comparison of direct and indirect leaf area index measuremen...
Hi, Sergio you could try the method proposed in: Fuentes, S., Palmer, A.R., Taylor, D., Zeppel, M., Whitley, R., Eamus, D., 2008. An automated procedure for estimating the leaf area index (LAI) of woodland ecosystems using digital imagery, MATLAB programming and its application to an examination of the relationship between remotely sensed and field measurements of LAI. Funct. Plant Biol. 35, 1070-1079. I tested it in cherry trees and it works fine (error < 20%). Cheers.
Hello Marcos,
Thank you very much for sending me the information about the paper from Fuentes et al (2008). I downloaded it right now. It contains very useful content. Tks a lot. Have a nice week. Regards, Sergio Ricardo
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