|
Abstract
|
Article Information:
Models for Predicting Stem Diameter from Crown Diameter of Open Grown Trees in Sondu-Nyando River Catchment, Kenya
J.M. Mugo, J.T. Njunge, R.E. Malimbwi, B.N. Kigomo, B.N. Mwasi and M.N. Muchiri
Corresponding Author: Joseph Mware Mugo
Submitted: 2010 December, 13
Accepted: 2011 January, 03
Published: 2011 March, 15 |
Abstract:
|
Information on stocks of trees on farm is scanty and in many cases lacking. Assessing the stocking
density of trees on farms require models relating tree bole diameter with its crown diameter. However, bolecrown
diameter models of open grown trees on farms is lacking in the Lake Victoria basin and indeed in Kenya.
The focus of this study was to develop regression equations that would predict individual tree Diameter at
Breast Height (DBH) from its crown diameter (Cd) for selected open grown tree species in Sondu-Nyando
River catchment. Stratified random sampling was used and GPS readings, DBH and Cd, collected from 20
unequal sized sample plots, along selected agro ecological gradients. The models were developed using DBH
and Cd measurements from 578 trees of five most dominant tree species (Cupressus lusitanica, Eucalyptus
saligna, Grevillea robusta, Persea americana and Croton megalocarpus). The DBH - Cd models displayed
good fit (R2 > 0.586). Persea americana had the highest adjusted R2 (0.875) and Eucalyptus saligna the lowest
(R2 = 0.586). F-test showed regression coefficients were significant in all the models. Residuals were more
concentrated in lower diameters, implying a negative exponential DBH distribution. The Linear, Exponential
and Power models performed well with the highest R2 (up to 0.875, 0.676 and 0.655). The developed models
are applicable across species groups and not across species.
Key words: species dominance, species groups, exponential function, power function, bole diameter, crown diameter ,
|
|
Abstract
|
PDF
|
HTML |
|
Cite this Reference:
J.M. Mugo, J.T. Njunge, R.E. Malimbwi, B.N. Kigomo, B.N. Mwasi and M.N. Muchiri, . Models for Predicting Stem Diameter from Crown Diameter of Open Grown Trees in Sondu-Nyando River Catchment, Kenya. Asian Journal of Agricultural Sciences, (2): 119-126.
|
|
|
|
 |
ISSN (Online): 2041-3890
ISSN (Print): 2041-3882 |
 |
| Information |
|
|
|
|
| Sales & Services |
|
|
|
|
