Advertisement

European Journal of Forest Research

, Volume 129, Issue 4, pp 543–562 | Cite as

Estimating leaf area index in different types of mature forest stands in Switzerland: a comparison of methods

  • Anne ThimonierEmail author
  • Isabella Sedivy
  • Patrick Schleppi
Original Paper

Abstract

Leaf area index (LAI) was estimated at 15 sites in the Swiss Long-Term Forest Ecosystem Research Programme (LWF) in 2004–2005 using two indirect techniques: the LAI-2000 plant canopy analyzer (Licor Inc.) and digital hemispherical photography, applying several exposure settings. Hemispherical photographs of the canopy were analysed using Hemisfer, a software package that offers several new features, which were tested here: (1) automatic thresholding taking the gamma value of the picture into account; (2) implementation of several equations to solve the gap-fraction inversion model from which LAI estimates are derived; (3) correction for ground slope effects, and (4) correction for clumped canopies. In seven broadleaved stands in our sample set, LAI was also estimated semi-directly from litterfall. The various equations used to solve the gap-fraction inversion model generated significantly different estimates for the LAI-2000 measurements. In contrast, the same equations applied in Hemisfer did not produce significantly different estimates. The best relationship between the LAI-2000 and the Hemisfer estimates was obtained when the hemispherical photographs were overexposed by one to two stops compared with the exposure setting derived from the reading of a spotmeter in a canopy gap. There was no clear general relationship between the litterfall and the LAI-2000 or the hemispherical photographs estimates. This was probably due to the heterogeneity of the canopy, or to biased litterfall collection at sites on steep slopes or sites subject to strong winds. This study introduces new arguments into the comparison of the advantages and drawbacks of the LAI-2000 and hemispherical photography in terms of applicability and accuracy.

Keywords

LAI Digital hemispherical photography LAI-2000 Litterfall 

Notes

Acknowledgments

We are very grateful to A. Brechbühl, N. Hajjar, O. Schramm, D. Trummer and the staff from the forest services for collecting the litterfall samples on the LWF plots. A. Brechbühl also participated in sorting the litterfall samples. We warmly thank O. Schramm and P. Waldner for their participation in the field campaign 2005. We also thank M. Nobis for his technical advice on the analysis of hemispherical photographs and S. Dingwall for editing the English. We gratefully acknowledge the financial support of the Federal Office for the Environment (FOEN).

References

  1. Anderson MC (1971) Radiation and crop structure. In: Sestak Z, Catsky J, Jarvis PG (eds) Plant photosynthetic production: manual of methods. Junk, The Hague, pp 412–466Google Scholar
  2. Becker M (1971) Une technique nouvelle d’utilisation des photographies hémisphériques pour la mesure du climat lumineux en forêt. Ann Sci For 28:425–442CrossRefGoogle Scholar
  3. Bréda NJJ (2003) Ground-based measurements of leaf area index: a review of methods, instruments and current controversies. J Exp Bot 54:2403–2417CrossRefPubMedGoogle Scholar
  4. Campbell GS (1986) Extinction coefficients for radiation in plant canopies calculated using an ellipsoidal inclination angle distribution. Agric For Meteorol 36:317–321CrossRefGoogle Scholar
  5. Chason JW, Baldocchi DD, Huston MA (1991) A comparison of direct and indirect methods for estimating canopy leaf area. Agric For Meteorol 57:107–128CrossRefGoogle Scholar
  6. Chen JM, Black TA (1991) Measuring leaf area index of plant canopies with branch architecture. Agric For Meteorol 57:1–12CrossRefGoogle Scholar
  7. Chen JM, Cihlar J (1995) Quantifying the effect of canopy architecture on optical measurements of leaf area index using two gap size analysis methods. IEEE Trans Geosci Remote Sens 33:777–787CrossRefGoogle Scholar
  8. Chen JM, Black TA, Adams RS (1991) Evaluation of hemispherical photography for determining plant area index and geometry of a forest stand. Agric For Meteorol 56:129–143CrossRefGoogle Scholar
  9. Chen JM, Rich PM, Gower ST, Norman JM, Plummer S (1997) Leaf area index of boreal forests: theory, techniques, and measurements. J Geophys Res- Atmos 102:29429–29443CrossRefGoogle Scholar
  10. Chen JM, Govind A, Sonnentag O, Zhang Y, Barr A, Amiro B (2006) Leaf area index measurements at Fluxnet-Canada forest sites. Agric For Meteorol 140:257–268CrossRefGoogle Scholar
  11. Coops NC, Smith ML, Jacobsen KL, Martin M, Ollinger S (2004) Estimation of plant and leaf area index using three techniques in a mature native eucalypt canopy. Austral Ecol 29:332–341CrossRefGoogle Scholar
  12. Cutini A, Matteucci G, Scarascia MG (1998) Estimation of leaf area index with the Li-Cor LAI2000 in deciduous forests. For Ecol Manage 105:55–65CrossRefGoogle Scholar
  13. Dufrêne E, Bréda N (1995) Estimation of deciduous forest leaf area index using direct and indirect methods. Oecologia 104:156–162CrossRefGoogle Scholar
  14. Englund SR, O’Brien JJ, Clark DB (2000) Evaluation of digital and film hemispherical photography and spherical densiometry for measuring forest light environments. Can J For Res-Rev Can Rech For 30:1999–2005CrossRefGoogle Scholar
  15. Ferment A, Picard N, Gourlet-Fleury S, Baraloto C (2001) A comparison of five indirect methods for characterizing the light environment in a tropical forest. Ann For Sci 58:877–891CrossRefGoogle Scholar
  16. Frazer GW, Trofymow JA, Lertzman KP (2000) Canopy openness and leaf area in chronosequences of coastal temperate rainforests. Can J For Res-Rev Can Rech For 30:239–256CrossRefGoogle Scholar
  17. Frazer GW, Fournier RA, Trofymow JA, Hall RJ (2001) A comparison of digital and film fisheye photography for analysis of forest canopy structure and gap light transmission. Agric For Meteorol 109:249–263CrossRefGoogle Scholar
  18. Graf Pannatier E, Dobbertin M, Schmitt M, Thimonier A, Waldner P (2007) Effects of the drought 2003 on forests in Swiss Level II plots. In: Eichhorn J (ed), Forests in a changing environment. Results of 20 years ICP forests monitoring, Göttingen, Germany, October 25–28, 2006. Schriften aus der Forstlichen Fakultät der Universität Göttingen und der Nordwestdeutschen Forstlichen Versuchsanstalt, vol 142, pp 128–135Google Scholar
  19. Holst T, Hauser S, Kirchgassner A, Matzarakis A, Mayer H, Schindler D (2004) Measuring and modelling plant area index in beech stands. Int J Biometeorol 48:192–201CrossRefPubMedGoogle Scholar
  20. Inoue A, Yamamoto K, Mizoue N, Kawahara Y (2004) Effects of image quality, size and camera type on forest light environment estimates using digital hemispherical photography. Agric For Meteorol 126:89–97CrossRefGoogle Scholar
  21. Lang ARG (1987) Simplified estimate of leaf area index from transmittance of the sun’s beam. Agric For Meteorol 41:179–186CrossRefGoogle Scholar
  22. Lang ARG, Xiang Y (1986) Estimation of leaf area index from transmission of direct sunlight in discontinuous canopies. Agric For Meteorol 37:229–243CrossRefGoogle Scholar
  23. Leblanc SG, Chen JM, Fernandes R, Deering DW, Conley A (2005) Methodology comparison for canopy structure parameters extraction from digital hemispherical photography in boreal forests. Agric For Meteorol 129:187–207CrossRefGoogle Scholar
  24. Li-Cor (1992) LAI-2000 plant canopy analyzer—Operating manual. LI-COR, Inc, LincolnGoogle Scholar
  25. Macfarlane C, Coote M, White DA, Adams MA (2000) Photographic exposure affects indirect estimation of leaf area in plantations of Eucalyptus globulus Labill. Agric For Meteorol 100:155–168CrossRefGoogle Scholar
  26. Martens SN, Ustin SL, Rousseau RA (1993) Estimation of tree canopy leaf area index by gap fraction analysis. For Ecol Manage 61:91–108CrossRefGoogle Scholar
  27. Miller JB (1967) A formula for average foliage density. Aust J Bot 15:141–144CrossRefGoogle Scholar
  28. Montes F, Pita P, Rubio A, Cañellas I (2007) Leaf area index estimation in mountain even-aged Pinus silvestris L. stands from hemispherical photographs. Agric For Meteorol 145:215–228CrossRefGoogle Scholar
  29. Mussche S, Samson R, Nachtergale L, De Schrijver A, Lemeur R, Lust N (2001) A comparison of optical and direct methods for monitoring the seasonal dynamics of leaf area index in deciduous forests. Silva Fenn 35:373–384Google Scholar
  30. Nilson T (1971) A theoretical analysis of the frequency of gaps in plant stands. Agric Meteorol 8:25–38CrossRefGoogle Scholar
  31. Nobis M (2003) Sideview 1.0—imaging software to extract vertical vegetation structure from true-colour photographs; http://www.appleco.de
  32. Nobis M, Hunziker U (2005) Automatic thresholding for hemispherical canopy-photographs based on edge detection. Agric For Meteorol 128:243–250CrossRefGoogle Scholar
  33. Norman JM, Campbell GS (1989) Canopy structure. In: Pearcy RW, Ehleringer JR, Mooney HA, Rundel PW (eds) Plant physiological ecology: field methods and instrumentation. Chapman and Hall, London, pp 301–325Google Scholar
  34. Planchais I, Pontailler JY (1999) Validity of leaf areas and angles estimated in a beech forest from analysis of gap frequencies, using hemispherical photographs and a plant canopy analyzer. Ann For Sci 56:1–10CrossRefGoogle Scholar
  35. Ross J (1981) The radiation regime and architecture of plant stands. Junk, The HagueGoogle Scholar
  36. Running SW, Coughlan JC (1988) A general model of forest ecosystem processes for regional applications. 1. hydrologic balance, canopy gas-exchange and primary production processes. Ecol Model 42:125–154CrossRefGoogle Scholar
  37. Running SW, Gower ST (1991) Forest-BGC, a general model of forest ecosystem processes for regional applications. 2. Dynamic carbon allocation and nitrogen budgets. Tree Physiol 9:147–160PubMedGoogle Scholar
  38. Schleppi P, Conedera M, Sedivy I, Thimonier A (2007) Correcting non-linearity and slope effects in the estimation of the leaf area index of forests from hemispherical photographs. Agric For Meteorol 144:236–242CrossRefGoogle Scholar
  39. Soudani K, Trautmann J, Walter JM (2001) Comparison of optical methods for estimating canopy openness and leaf area index in broad-leaved forests. C R Acad Sci Ser III-Sci Vie 324:381–392Google Scholar
  40. Strachan IB, McCaughey JH (1996) Spatial and vertical leaf area index of a deciduous forest resolved using the LAI-2000 plant canopy analyzer. For Sci 42:176–181Google Scholar
  41. Thimonier A, Schmitt M, Cherubini P, Kräuchi N (2001) Monitoring the Swiss forest: building a research platform. In: Anfodillo T, Carraro V (eds) Monitoraggio ambientale: metodologie ed applicazioni Atti del XXXVIII Corso di Cultura in Ecologia, 2001. San Vito di Cadore, Centro Studi per l’Ambiente Alpino, Università degli Studi di Padova, pp 121–134Google Scholar
  42. Wang YS, Miller DR, Welles JM, Heisler GM (1992) Spatial variability of canopy foliage in an oak forest estimated with fisheye sensors. For Sci 38:854–865Google Scholar
  43. Weiss M, Baret F, Smith GJ, Jonckheere I, Coppin P (2004) Review of methods for in situ leaf area index (LAI) determination Part II. Estimation of LAI, errors and sampling. Agric For Meteorol 121:37–53CrossRefGoogle Scholar
  44. Zhang Y, Chen JM, Miller JR (2005) Determining digital hemispherical photograph exposure for leaf area index estimation. Agric For Meteorol 133:166–181CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Anne Thimonier
    • 1
    Email author
  • Isabella Sedivy
    • 1
  • Patrick Schleppi
    • 1
  1. 1.WSL-Swiss Federal Institute for Forest, Snow and Landscape ResearchBirmensdorfSwitzerland

Personalised recommendations