Cost-productivity analysis of South African pine sawtimber mechanised cut-to-length harvesting. Issue 4 (1st October 2016)

• Record Type: Journal Article
• Authors: Williams, Chloe; Ackerman, Pierre
• Is Part Of: Southern forests. Volume 78:Issue 4(2016)
• Page Start: 267
• Page End: 274
• Publication Date: 2016-10-01
• Subjects: forwarder -- fuel consumption -- harvester -- plantation -- productivity -- time study -- utilisation; Forests and forestry -- Southern Hemisphere -- Periodicals; Forests and forestry -- Periodicals; 634.9091814
• DOI: 10.2989/20702620.2016.1183096
• Languages: English
• ISSNs: 2070-2620

Abstract

Abstract : The South African forestry industry is experiencing an increase in the number of fully mechanised timber-harvesting systems. Understanding the productivity of these systems, for which data is currently limited for South Africa, is an important step to maximise the utilisation of machines being used. A time study of a mechanised cut-to-length system was conducted in Pinus elliottii sawtimber plantations in the Southern Cape forestry region of South Africa. A harvester and a forwarder were studied with the intention of analysing the division of work time amongst work elements, modelling each machine's productivity and cost, and estimate fuel consumption. For the harvester's productivity, a multiple regression model was developed using diameter at breast height (DBH), average distance moved per work cycle and slope class as predictors (adjusted R 2 = 0.80). The harvester had a mean productivity of 33.6 m 3 per productive machine hour (PMH0 ) under the current conditions with most of the productive time being used in the moving element. It consumed 25.5 L PMH0 −1 of diesel on average. The forwarder's fuel consumption was calculated as 16.8 L PMH0 −1, while productivity was 46.8 m 3 PMH0 −1 . The forwarder spent the longest portion of the work cycle in the loading and unloading phases. A productivity regression model was created that included load size and distance moved during the driving in the loaded phase (adjusted R 2 = 0.78).