On the potential of kriging for estimation and mapping of forest plantation stock (Case study: Beneshki plantation)

Document Type : Research article

Authors

1 Assistant Prof., Research Institute of Forests and Rangelands

2 Professor, Institute of Forest Inventory and Remote Sensing. Georg-August-Universität Göttingen

Abstract

This research was conducted to investigate on spatial structure and estimationof tree attributes in a forest plantation in the Caspian region of Iran. Field sampling was performed based on a 50m×125m systematic grid in a maple stand (Acer velutinum Boiss.) at age of 18 years using circular samples of 200m2 area. Overall, 96 sample plots were measured in 63 hectare and 14.25 hectare was inventoried as full census area, as well. Experimental variograms for forest stem basal area, stem density and tree height attributes were calculated and plotted using the geo-referenced inventory plots. The calculated variograms of basal area and height showed a high spatial autocorrelation, which fitted by spherical models. However, stem density showed a large amount of nugget effect. Based on variography results, optimal sampling distance for stem basal area and density obtained 165m and 350m, respectively. Estimations for basal area and height were made by ordinary block (15m×15m) kriging and cross-validation results showed that all the estimations are accurate. Furthermore, the estimated kriged mean of basal area showed no significant difference to the real mean in the full census area, while kriging in term of statistical precision was two times better than sampling. Therefore, geostatistics is able to capture and describe the spatial variability as well as estimates tree attributes (not stem density) in this kind of forest plantation, accurately.

Keywords


- اخوان، ر.، 1383. بررسی استفاده از روش زمین آمار در برآورد موجودی جنگل در مقایسه با روش کلاسیک در جنگلهای خزری شمال ایران. رساله دکتری، دانشکده منابع طبیعی، دانشگاه تهران، 64 صفحه. 
- بی‌نام، 1365. طرح جامع جنگلهای شمال کشور (مرحله مقدماتی)، حوضه‌های آبخیز 33-32-31. سازمان جنگلها و مراتع کشور، دفتر فنی جنگل‌داری. 120 صفحه.
- حسنی پاک، ع.ا.، 1377. زمین‌آمار (ژئواستاتیستیک). انتشارات دانشگاه تهران، 314 صفحه.
- زبیری، م.، 1373. آماربرداری در جنگل. انتشارات دانشگاه تهران، 401 صفحه.
- قنبری، ف.، 1387. بررسی پیش‌بینی توزیع مکانی برخی خصوصیات آلومتریک جنگل با استفاده از زمین‌آمار و GIS درجنگل آموزشی و پژوهشی دکتر بهرام‌نیا. پایان‌نامه کارشناسی ارشد، دانشگاه علوم کشاورزی و منابع طبیعی گرگان. 155 صفحه.
- محمدی، ج.، شتایی جویباری، ش.، حبشی، ه. و یغمایی، ف.، 1387. مقایسه سنجش از دور و زمین‌آمار در برآورد تعداد درختان در هکتار در جنگلهای بلوط لوه گرگان. مجله علوم کشاورزی و منابع طبیعی، ویژه‌نامه منابع طبیعی، 15 (1): 21-10.
- Bellehumeur, C. and Legendre, P., 1998. Multiscale sources of variation in ecological variables: modeling spatial dispersion, elaborating sampling designs. Landscape Ecology, 13: 15-25.
- Biondi, F., Myers, D.E. and Avery, C.C., 1994. Geostatistically modeling stem size and increment in an old-growth forest. Canadian Journal of Forest Research, 24: 1354-1368.
- Cressie, N.A.C., 1993. Statistics for spatial data. John Willy and Sons, Inc., New York. 900 p.
- Duplat, P. and Peyrotte, G., 1981. Inventaire et accroissement, Annexe 4, Office national des Forèts, Section technique, Paris. 120 p.
- Freeman, E.A. and Moisen, G.G., 2007. Evaluating kriging as a tool to improve moderate resolution maps of forest biomass. Environmental Monitoring and Assessment, 128: 395-410.
- Ganawa, E.S.M. and Mohammad Sharif, A.R., 2003. Spatial variability of total nitrogen and available phosphorus of large rice field in Sawah Sepadan Malaysia. Science Asia Journal, 29: 7-12.
- Goovaerts, P., 1997. Geostatistics for natural resources evaluation. OxfordUniversity Press, New York. 483 p.
- Guibal, D., 1973. L´ estimation des oukoumés du Gabon, note interne 333, Centre de Morphologie Mathématique, Fontainebleau, France. 92 p.
- Gunnarsson, F., Holm, S., Holmgren, P. and Thuresson, T., 1998. On the potential of kriging for forest management planning. Scandinavian Journal of Forest Research, 13: 237- 245.
- Holmgren, P. and Thuresson, T., 1997. Applying objectively estimated and spatially continuous forest parameters in tactical planning to obtain dynamic treatment units. Forest Science, 43: 317-326.
- Houiller, F., 1986. Echantillonnage et modélisation de la dynamique des peuplements forestiers, thèse de doctorat, Université Claude Bernard, LyonI. 82 p.
- Husch, B., Miller, C.I. and Beers, T.W., 1982. Forest mensuration. 3rd ed. John Wiley & Sons, inc., New York. 443 p.
- Isaaks, E.H. and Srivastava, R.M., 1989. An introduction to applied geostatistics. OxfordUniversity Press, New York. 561p.
- Jost, A., 1993. Geostatistische analyse des Stichprobenfehlers systematischer Stichproben. Ph.D. thesis, academic press, University of Freiburg in Breisgau, Germany, 113 p.
- Kint, V., Meirvenne, M.V., Nachtergale, L., Geudens, G. and Lust, N., 2003. Spatial methods for quantifying forest stand structure development: a comparison between nearest neighbour indices and variogram analysis. Forest science, 49 (1): 36-49.
- Krige, D.G., 1951. A statistical approach to some mine valuation and allied problems on the Witwatersrand. Master’s thesis, University of Witwatersrand, 190 p.
- Mandallaz, D., 1993. Geostatistical methods for double sampling schemes: application to combined forest inventory. Technical report, ETH Zürich, chair of forest inventory and planning, 33 p.
- Mandallaz, D., 2000. Estimation of the spatial covariance in universal kriging: Application to forest inventory. Environmental and ecological statistics, 7: 263-284.
- Marbeau, P., 1976. Géostatistique forestière: état actuel et développements nouveaux pour l´ aménagement en forêt tropicale thèse, centre de Morphologie Mathématique, ENSM, Paris. 105 p.
- Matheron, G., 1965. La théorie des variables regionalisées et ses applications, Masson, Paris. 72 p.
- Montes, F., Hernandez, M.J. and Canellas, I., 2005. A geostatistical approach to cork production sampling in Quercus suber forests. Canadian Journal of Forest Research, 35: 2787-2796.
- Nanos, N. and Montero, G., 2001. Spatial prediction of diameter distribution models. Forest ecology and management, 161: 147-158.
- Nanos, N., Calama, R., Montero, G. and Gil, L., 2004. Geostatistical prediction of height/diameter models. Forest ecology and management, 195: 221-235.
- Samra, J.S., Gill, H.S. and Bhatia, V.K., 1989. Spatial stochastic modeling of growth and forest resource evaluation. Forest Science, 35: 663-676.   
- Tuominen, S., Fish, S. and Poso, S., 2003. Combining remote sensing, data from earlier inventories, and geostatistical interpolation in multi-source forest inventory. Canadian Journal of Forest Research, 33: 624- 634.
- Webster, R. and Oliver, M.A., 2000. Geostatistics for environmental scientists. Wiley press, 271 p.
- Zahedi Amiri, Gh., 1998. Relation between ground vegetation and soil characteristic in a mixed hardwood stand, Ph.D. thesis, academic press, University of Gent, Belgium, 319 p.