Skip to main content
SpringerLink
Log in

On the nature of canopy illumination due to differences in elemental orientation and aggregation for radiative transfer

  • Short Note
  • Published:
International Journal of Biometeorology Aims and scope Submit manuscript

Abstract

The nature of canopy radiative transfer mechanism (CRTM) describes the amount of beam penetration through a canopy and governs the nature of canopy illumination, i.e. the abundance of sunlit and shaded portions. Realistic representation of canopy illumination is critical for simulating various canopy biophysical processes associated with vegetated land surfaces. The adequate representation of CRTM can be attributed to the parameterizations of the two main canopy characteristics: the foliage projection (G-function) and the clumping effect (Ω function). Herein, using various types of G and Ω functions developed in a previous study, I tested 15 CRTM scenarios that combine different types of G and Ω functions to predict the dynamics of sunlit fraction (ε) of canopies having a wide range of plant area index (Ptotal) at various solar zenith angles (SZAs). It was observed that, for a given Ptotal, ε decreases as the SZA increases. However, ε significantly changed in accordance with the type of G and Ω functions used. Scenarios that employed random distribution of elements in space (S-4, S-9, and S-14) consistently returned larger ε values even at lower SZAs. This means that ignoring the clumping behavior of canopies could result in greater proportion of sunlit elements thereby reducing the beam penetration deeper into the canopy as opposed to those canopies where the elements are more aggregated. Beyond 70° SZA, almost all the scenarios returned similar ε values for a given Ptotal, which implied that the methods used is less sensitive at higher SZAs. The values of ε calculated by all the scenarios were significantly different from the S-6 (the ideal case). This observation highlights the importance of explicitly describing the G and Ω functions to adequately depict canopy illumination conditions.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3

References

  • Anisimov O, Fukshansky L (1997) Optics of vegetation: implications for the radiation balance and photosynthetic performance. Agric For Meteorol 85(1–2):33–49

    Article  Google Scholar 

  • Alton PB, Ellis R, Los SO, North PR (2007) Improved global simulations of gross primary product based on a separate and explicit treatment of diffuse and direct sunlight. J Geophys Res 112, D07203. doi:10.1029/2006JD008022

    Google Scholar 

  • Baldocchi DD, Hutchison BA, Matt DR, McMillen RT (1985) Canopy radiative-transfer models for spherical and known leaf inclination angle distributions: a test in an oak hickory forest. J Appl Ecol 22(2):539–555

    Article  Google Scholar 

  • Berbigier P, Bonnefond J-M (1995) Measurements and modeling of radiation transmission within a stand of maritime pine (Pinus pinaster Aït.). Ann des Sci forestières 52:23–42

    Article  Google Scholar 

  • Bonan GB (1989) A computer-model of the solar-radiation, soil-moisture, and soil thermal regimes in boreal forests. Ecol Model 45:275–306

    Article  Google Scholar 

  • Campbell GS (1990) Derivation of an angle density-function for canopies with ellipsoidal leaf angle distributions. Agric For Meteorol 49(3):173–176

    Article  Google Scholar 

  • Chen JM (1996) Optically-based methods for measuring seasonal variation in leaf area index of boreal conifer forests. Agric For Meteorol 80:135–163

    Article  Google Scholar 

  • Chen JM, Mo G, Pisek J, Liu J, Deng F, Ishizawa M, Chan D (2012) Effects of foliage clumping on the estimation of global terrestrial gross primary productivity, Global Biogeochem. Cycles 26, GB1019. doi:10.1029/2010GB003996

    Article  Google Scholar 

  • Chen JM, Liu J, Cihlar J, Guolden ML (1999) Daily canopy photosynthesis model through temporal and spatial scaling for remote sensing applications. Ecol Model 124:99–119

    Article  CAS  Google Scholar 

  • Chen JM, Rich PM, Gower TS, Norman JM, Plummer S (1997) Leaf area index of boreal forests: theory, techniques, and measurements. J Geophys Res 102:29,429–29,444

    Article  Google Scholar 

  • Chen JM, Black TA (1991) Measuring leaf-area index of plant canopies with branch architecture. Agric For Meteorol 57(1–3):1–12

    Article  Google Scholar 

  • Chen JM, Menges CH, Leblanc SG (2005) Global mapping of foliage clumping index using multi-angular satellite data. Remote Sensing Environ 97(4):447–457

    Article  Google Scholar 

  • De Pury DGG, Farquhar GD (1997) Simple scaling of photosynthesis from leaves to canopies without the errors of big-leaf models. Plant, Cell Environ 20:537–557. doi:10.1111/j.1365-3040.1997.00094.x

    Article  Google Scholar 

  • Dickinson RE, Sellers AH, Kennedy PJ, Wilson MF (1986) ‘Biosphere-atmosphere transfer scheme (BATS) for the NCAR community climate model’, InNCAR Tech. Note TN-275, National Center for Atmosphere Research, Boulder, Colorado, USA.

  • Fassnacht KS, Gower ST, Norman JM, Mcmirtrie RE (1994) A comparison of optical and direct methods in estimating foliage surface area in forests. Agric For Meteorol 71:183–207

    Article  Google Scholar 

  • Goel NS, Strebel DE (1984) Simple beta distribution representation of leaf orientation in vegetation canopies. Agrono J 76(5):800–802

    Article  Google Scholar 

  • Govind A, Guyon D, Roujean J-L, Yauschew-Raguenes N, Kumari J, Pisek P, Wigneron J-P (2013) Effects of canopy architectural parameterizations on the modeling of radiative transfer mechanism. Ecol Model 251(2013):114–126

    Article  Google Scholar 

  • Govind A, Chen JM, McDonnell J, Kumari J, Sonnentag O (2010) Effect of lateral hydrological processes on photosynthesis and evapotranspiration. Ecohydrology.3. (doi: 10.1002/eco.141).

  • Govind A, Chen JM, Margolis H, Ju W, Sonnentag O, Giasson MA (2009a) A spatially explicit hydro-ecological modeling framework (BEPS-TerrainLab V2.0): model description and test in a boreal ecosystem in Eastern North America. J Hydrol 367:200–216. doi:10.1016/j.jhydrol.2009.01.006

    Article  CAS  Google Scholar 

  • Govind A, Chen JM, Ju W (2009b) Spatially explicit simulation of hydrologically controlled carbon and nitrogen cycles and associated feedback mechanisms in a boreal ecosystem. Journal of Geophysical Research 114, G02006. doi:10.1029/2008JG000728

    Article  Google Scholar 

  • Govind A, Chen JM, Bernier PY, Margolis H, Guindon L, Beaudoin A (2011) Spatially distributed modeling of the long-term carbon balance of a boreal landscape. Ecological Modeling 222(15):2780–2795

    Article  CAS  Google Scholar 

  • Kucharik CJ, Norman JM, Gower ST (1999) Characterization of radiation regimes in nonrandom forest canopies: theory, measurements, and a simplified modeling approach. Tree Physiology 19(11):695–706

    Article  Google Scholar 

  • Lang ARG, Xiang Y (1986) Estimation of leaf area index from transmission of direct sunlight in discontinuous canopies. Agric For Meteorol 37(3):229–243

    Google Scholar 

  • Lemeur R, Blad BL (1974) A critical review of light models for estimating the shortwave radiation regime of plant canopies. Agric Meteorol 14(255):286

    Google Scholar 

  • Monsi M, Saeki T (1953) Über den Lichtfaktor in den Pflanzengesellschaften und seine Bedeutung für die Stoffproduktion. Japanese Journal of Botany 14:22–52

    Google Scholar 

  • Nilson T, Ross J (1997) Modeling radiative transfer through forest canopies: implications for canopy photosynthesis and remote sensing. The use of remote sensing in the modeling of forest productivity, pp. 23–60

  • Nilson T (1971) Theoretical analysis of frequency of gaps in plant stands. Agric Meteorol 8(1):25–38

    Article  Google Scholar 

  • Norman JM (1982) Simulation of microclimates. In: Hatfield JL, Thomason IJ (eds) Biometeorology in Integrated Pest Management. Academic, San Diego, Calif, pp 65–99

    Chapter  Google Scholar 

  • Pisek J, Chen JM, Nilson T (2011) Estimation of vegetation clumping index using MODIS BRDF data. International Journal of Remote Sensing 32(9):2645–2657

    Article  Google Scholar 

  • Ross J (1981) The radiation regime and architecture of plant stands. Dr. W. Junk, Norwell, Mass., USA, p. 391

  • Stenberg P, Linder S, Smolander H, Flower-Ellis J (1994) Performance of the LAI- (2000) Plant canopy analyzer in estimating leaf area index of some Scotspine stands. Tree Physiology 14:981–995

    Google Scholar 

  • Sterck FJ, Schieving F (2007) 3-D growth patterns of trees: effects of carbon economy, meristem activity, and selection. Ecol Monogr 77:405–420. doi:10.1890/06-1670.1

    Article  Google Scholar 

  • Walter J-MN, Fournier RA, Soudani K, Meyer E (2003) Integrating clumping effects in forest canopy structure: an assessment through hemispherical photographs. Canadian Journal of Remote Sensing 29:388–410

    Article  Google Scholar 

  • Wang Y-P, Leuning R (1998) A two-leaf model for canopy conductance, photosynthesis, and partitioning of available energy I: model description and comparison with a multi-layered model. Agric For Meteorol 91:89–111. doi:10.1016/S0168-1923(98)00061-6

    Article  Google Scholar 

  • Zhang YQ, Chen JM, Miller JR (2005) Determining digital hemispherical photograph exposure for leaf area index estimation. Agric For Meteorol 133(1–4):166–181

    Article  Google Scholar 

Download references

Acknowledgments

Prof. Jing Chen (U of Toronto) is acknowledged for inspiring me with his works on CRTM. I thank Dr. Jean-Louis Roujean (CNRM), Dr. Jyothi Kumari, Mr. Alain Kruszewski and Ms. Sylvia Dayau (EPHYSE) who helped me to collect Ω in the experimental campaign mentioned in Govind et al. (2013).

Author information

Authors and Affiliations

  1. INRA, UR 1263 EPHYSE, F-33140 Villenave d’Ornon, Centre INRA Bordeaux, Aquitaine, France

    Ajit Govind

Authors
  1. Ajit Govind
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Ajit Govind.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Govind, A. On the nature of canopy illumination due to differences in elemental orientation and aggregation for radiative transfer. Int J Biometeorol 58, 1803–1809 (2014). https://doi.org/10.1007/s00484-013-0769-1

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00484-013-0769-1

Keywords

Search

Navigation