Allometric biomass equations for young broadleaved trees in plantations in Romania

Abstract The possibility of estimating young trees biomass is rather limited because forest yield tables are constructed starting from higher thresholds of proxy, such as diameter or height, and lack of availability of allometric equations. The aim of this study is to provide species-specific and general biomass equations for young plants often used for plantations on marginal lands in southern and eastern Romania. Power functions based on log-transformed data were applied to seven tree species (Robinia pseudoacacia (L.), Quercus sp., Populus alba (L.), Gleditsia triacanthos (L.), Elaeagnus angustifolia (L.), Salix alba (L.) and Fraxinus excelsior (L.)), one shrub (Rosa canina L.) and to the overall dataset with all the species pooled together (406 plants), using the diameter at collar height (Dch), diameter at breast height (Dbh) or height (H) as single predictor. Dch resulted as being the best predictor for each compartment for very young trees, but H also proved to be a promising individual predictor both for species-specific or general equations. Dbh could satisfactorily predict the aggregated aboveground biomass, but generally could not adequately estimate all biomass components (i.e., belowground biomass or foliage). The goodness of regression was lowest for the foliage and highest for the stem and aggregated biomass compartments. The scaling coefficient (a) and exponent (b) of power functions were influenced both by species-specific factors and by the growth stage of the trees. Parameters to be used for a general equation were also provided for each biomass compartment and predictor. Using Dch as independent variable, we observed that the value of the general scaling exponent estimated to predict total aboveground biomass was the same as the value (2.66) predicted by the WBE functional model. Using Dbh as predictor for the general allometric equation, the resulting value of b (2.36) coincided with the values empirically estimated by previous studies. Equations were finally compared against three independent datasets. Parameters provided by the general equation highlighted permanent overestimation for aggregated biomass compartments and underestimation for branches or roots, but always fell into the range provided by the upper and lower values estimated for a and b. This suggests that, at least for young trees, our equation could be applied without regard for local fertility conditions or plantation management.

[1]  Q. Ketterings,et al.  Reducing uncertainty in the use of allometric biomass equations for predicting above-ground tree biomass in mixed secondary forests , 2001 .

[2]  Karl J Niklas,et al.  A phyletic perspective on the allometry of plant biomass-partitioning patterns and functionally equivalent organ-categories. , 2006, The New phytologist.

[3]  Unfccc.  Kyoto Protocol to the United Nations Framework Convention on Climate Change , 1997 .

[4]  Lonnie W. Aarssen,et al.  The interpretation of stem diameter–height allometry in trees: biomechanical constraints, neighbour effects, or biased regressions? , 1999 .

[5]  F. Wagner,et al.  Good Practice Guidance for Land Use, Land-Use Change and Forestry , 2003 .

[6]  James H. Brown,et al.  A general model for the structure and allometry of plant vascular systems , 1999, Nature.

[7]  M. Ter-Mikaelian,et al.  Biomass equations for sixty-five North American tree species , 1997 .

[8]  Giorgio Alberti,et al.  Aboveground biomass relationships for mixed ash (Fraxinus excelsior L. and Ulmus glabra Hudson) stands in Eastern Prealps of Friuli Venezia Giulia (Italy) , 2005 .

[9]  B. Enquist.  Universal scaling in tree and vascular plant allometry: toward a general quantitative theory linking plant form and function from cells to ecosystems. , 2002, Tree physiology.

[10]  Maurizio Mencuccini,et al.  On simplifying allometric analyses of forest biomass , 2004 .

[11]  Dimitris Zianis,et al.  Predicting mean aboveground forest biomass and its associated variance , 2008 .

[12]  Allometric biomass equations for Scots pine (Pinus sylvestris L.) seedlings during the first years of establishment in dense natural regeneration , 2004 .

[13]  Christian Wirth,et al.  Generic biomass functions for Norway spruce in Central Europe--a meta-analysis approach toward prediction and uncertainty estimation. , 2004, Tree physiology.

[14]  Filippo Simini,et al.  Self-similarity and scaling in forest communities , 2010, Proceedings of the National Academy of Sciences.

[15]  M. Schoeneberger,et al.  Developing above-ground woody biomass equations for open-grown, multiple-stemmed tree species : Shelterbelt-grown russian-olive , 2007 .

[16]  K. Niklas.  Mechanical Properties of Black Locust ( Robinia pseudoacacia L.) Wood. Size- and Age-dependent Variations in Sap- and Heartwood , 1997 .

[17]  M. Carrer,et al.  Towards a functional and simplified allometry for estimating forest biomass , 2006 .

[18]  Hanns-Christof Spatz,et al.  Growth and hydraulic (not mechanical) constraints govern the scaling of tree height and mass. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[19]  L. Saint-Andre,et al.  Ontogeny partly explains the apparent heterogeneity of published biomass equations for Fagus sylvatica in central Europe , 2011 .

[20]  Karl J. Niklas,et al.  Botanical Scaling. (Book Reviews: Plant Allometry. The Scaling of Form and Process.) , 1994 .

[21]  J. Knoepp,et al.  Effects of forest management on soil carbon: results of some long-term resampling studies. , 2002, Environmental pollution.

[22]  Testing the allometric scaling laws. , 2004, Journal of theoretical biology.

[23]  D. Sprugel,et al.  Correcting for Bias in Log‐Transformed Allometric Equations , 1983 .

[24]  M. Casado,et al.  Funciones de estimación de la biomasa aérea de varias especies del matorral mediterráneo del centro de la península Ibérica , 1996 .

[25]  B. Parresol.  Assessing Tree and Stand Biomass: A Review with Examples and Critical Comparisons , 1999, Forest Science.

[26]  I. Abrudan,et al.  Biomass Conversion and Expansion Factors for Young Norway Spruce (Picea abies (L.) Karst.) Trees Planted on Non-Forest Lands in Eastern Carpathians , 2010 .

[27]  Raisa Mäkipää,et al.  Biomass and stem volume equations for tree species in Europe , 2005, Silva Fennica Monographs.

[28]  Sandra A. Brown.  Measuring carbon in forests: current status and future challenges. , 2002, Environmental pollution.

[29]  Comparison between empirical and theoretical biomass allometric models and statistical implications for stem volume predictions , 2006 .

[30]  Chuankuan Wang,et al.  Biomass allometric equations for 10 co-occurring tree species in Chinese temperate forests , 2006 .

[31]  Matthias Peichl,et al.  Allometry and partitioning of above- and belowground tree biomass in an age-sequence of white pine forests , 2007 .

[32]  Lutz Fehrmann,et al.  General considerations about the use of allometric equations for biomass estimation on the example of Norway spruce in central Europe , 2006 .

[33]  R. K. Bamber,et al.  Sapwood and heartwood: a review , 1985 .

[34]  James H. Brown,et al.  Allometric scaling of production and life-history variation in vascular plants , 1999, Nature.

[35]  Christian Wirth,et al.  Evaluating tree carbon predictions for beech (Fagus sylvatica L.) in western Germany , 2004 .

[36]  R. Bamber.  Heartwood, its function and formation , 1976, Wood Science and Technology.

[37]  T. Tokola,et al.  Functions for estimating stem diameter and tree age using tree height, crown width and existing stand database information , 2005 .