Estimation on optical porosity or canopy closure for a forest stand with hemispherical images

Abstract

Abstract: Forest structure can not only influence the inhabited and biological factors in stands,but also determine the ecological functions of forest ecosystems.With the help of adjusting stand structure,reasonable forest management can come true.As one of the important indexes of forest structure,stand light transmission porosity or canopy closure can reflect the redistribution of light,water and other environmental factors entered the stand through forest canopy.It also plays a vital role on both forest management and many fine studies on forest ecology.Therefore,it is necessary to find a reasonable and accurate method to measure the light transmission porosity or canopy closure of a stand.This paper gave a detailed introduction on how to use hemispherical photograph to estimate canopy closure on the basis of the former related studies,and discussed in detail the selection of effective area of hemispherical photography,and some problems we have to pay attention to.

Key words: Urban soil, Heavy metal, Concentration, Principal component analysis, Nanjing

CLC Number:

S718.5

ZHU Jiaojun, KANG Hongzhang, HU Lile. Estimation on optical porosity or canopy closure for a forest stand with hemispherical images[J]. cje, 2005, (10): 1234-1240.

References

[1] 关文彬,李春平,李世锋,等.2002.林带疏透度数字化测度方法的改进及其应用研究[J].应用生态学报,13(6):651 657.
[2] 朱教君,李凤芹,松崎健,等.2002.间伐对黑松海岸林更新的影响[J].应用生态学报,13(11):1361～1367.
[3] 朱教君.2003.透光分层疏透度测定及其在次生林结构研究中的应用[J].应用生态学报,14(8):1229～1233.
[4] 李广文,李伟倩.1989.鱼眼全景像片在近景摄影测量中的应用[J].同济大学学报,17(1):89～97.
[5] 陈晃明,陈向颖.1989.鱼眼镜头光学设计[J].北京理工大学学报,9(3):35～42.
[6] 姜凤岐,付梦华,徐吉岩.1989.应用"数字图象处理法"测定林带疏透度[A] .见:向开馥.防护林研究[C] .哈尔滨:东北林业大学出版社,399～401.
[7] 姜凤岐,周新华,付梦华,等.1994.林带疏透度模型及其应用[J].应用生态学报,5:251 255.
[8] 姜凤岐,朱教君,周新华.1999.林带连续性经济效应模型及其应用的研究[J].林业科学,35(1):16～21.
[9] 姜凤岐,朱教君,曾德慧,等.2003.防护林经营学[M].北京:中国林业出版社,128～155.
[10] Baker PJ, Wilson JS. 2000. A quantitative technique for the identification of canopy stratification in tropical and temperate forest[J]. For. Ecol. Manag. , 127:77～86.
[11] Bean A, Alperi RW, Federer CA. 1975. A method for categorizing shelterbelt porosity[J]. Agric. Meteorol., 14:417 ～ 429.
[12] Chen JM, Black TA. 1991. Evaluation of hemispherical photography for determining plant area index and geometry of forest stand[J]. Agric . For. Meteorol . , 56:129～ 143.
[13] Englund SR, O'sBrien JJ, Clark DB. 2000. Evaluation of digital and film hemispherical photography and spherical densiometry for measuring forest light environments[J]. Can. J. For. Res., 30:1999～2005.
[14] Fouruier RA, Landry R, August NM, et al. 1996. Modelling light obstruction in three conifer forests using hemispherical photography and fine tree architecture [J]. Agri. For. Meteorol.,82:47～72.
[15] Frazer GW, Fournier A, Trofymous JA, et al. 2001. A comparison of digital and film fisheye photography for analysis of forest canopy structure and gap light[J]. Agric. For. Meteorol., 109:249～ 263.
[16] Heisler GM, DeWalle DR. 1988. Effects of windbreak structure on wind flow[J]. Agric. Ecosys. Environ., 22/23:41 ～69.
[17] Herbert TJ. 1987. Area projections of fisheye photographic lenses[J]. Agric. For. Meteorol. ,39:215～ 223.
[18] Jennings SB, Brown ND, Shell D. 1999. Assessing forest canopies and understorey illumination: canopy closure, canopy cover and other measures[J]. Forestry, 72: 59 ～ 74.
[19] Kenney WA. 1987. A method for estimating windbreak porosity using digitized photographic silhouettes [J]. Agric. For. Meteorol., 39:91 ～ 94.
[20] Loeffler AE, Gordon AM, Gillespie TJ. 1992. Optical porosity and windspeed reduction by coniferous windbreaks in Southern Ontario[J]. Agrofor. Sys., 17:119 ～ 133.
[21] Machado JL, Reich PB. 1999. Evaluation of several measures of canopy openness as predictiors of photosynthetic photon flux density in deeply shaded conifer-dominated forest understory [J].Can. J . For. Res., 29:1438～ 1444.
[22] Myers GP, Newton AC, Melgarejo O. 2000. The influence of canopy gap size on natural regeneration of Brazil nut ( Bertholletia excelsa ) in Bolvia[J]. For. Ecol. Manag., 127:119 ～ 128.
[23] Patrick M, John G, Antonio CM. 2000. Photographic method to measure the vertical distribution of leaf area density in forests[J]. Agric. For. Meteorol., 102:105 ～ 11 1.
[24] Steege H. 1994. Hemiphot, a programme to analyze vegetation indices, light and light quality from hemispherical photographs[M] . Wageningen, Netherlands The Tropenbos Foundation.
[25] Wang YS, Miller DR, Welles JM, et al. 1992. Spatial variability of canopy foliage in an Oak forest estimated with fisheye sensors[J]. For. Sci., 38:854 ～ 865.
[26] Yamamoto K. 2000. Estimation of the canopy - gap size using two photographs taken at different heights[J]. Ecol. Res., 12:203 ～ 208.
[27] Yasugi R, Kozeki H, Furutani M, et al. 1996. Biology Dictionary[M]. Tokyo Japan: Iwanami Shoten Press, . (in Japanese)
[28] Zhu J J, Matsuzaki T, Gonda Y, et al. 2000. Estimation of optical stratification porosity (OSP) in a pine coastal forest with different thinning intensities using hemispherical photographic silhouettes[J]. Bull. Facu. Agric. Niigata. Univ., 53 ( 1 ): 55 ～ 70.
[29] Zhu J J, Matsuzaki T, Gonda Y. 2003. Optical stratification porosity as a measure of vertical canopy structure in a Japanese coastal forest[J]. For. Ecol. Manag., 173( 1 - 3): 89 ～ 104.
[30] Zhu JJ, Matsuzaki T, Jiang FQ. 2004. Wind on Tree Windbreaks[M] . Beijing: China Forestry Publishing House, 10 ～ 47.