Productivity Analysis of Tree-Length Harvesting using Farm Tractor in a Nordmann Fir Stand in Turkey

An increasing demand for forest products incites a large number of log transportation operations, which may lead to negative consequences for the soil and the ecosystem as a whole. This paper presents a mathematical model to estimate the soil deformation and compaction processes under the influence of individual components of the skidding system, such as the forwarder, limbs, butts, and tops of tree-lengths in high latitudes, permafrost soil, and forests of the cryolithic zone. The effectiveness of the proposed model was evaluated according to experimental results. Comparative analysis showed that the calculated data differ from the experimental data by no more than 10%. The deformation of the soil by the bunch of tree-length logs occurs due to shearing processes. It has been established that the initial vertical stress exceeds the radial stress by 30–40%. The result of estimating the dependency of the shelterbelt width on the number of tree-length logs showed that the limit values for logs amount to 4–6 units for the mild, medium, and solid soil categories. The obtained results and the developed model will allow for a qualitative and quantitative assessment of the technological impact on the soil during the projecting of maps for logging operations.

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Effects of riparian forest thinning by two types of mechanical harvest on stream fish and habitat in northern Minnesota

Canadian Journal of Forest Research ◽

10.1139/x07-157 ◽

2008 ◽

Vol 38 (2) ◽

pp. 247-256 ◽

Cited By ~ 14

Author(s):

Nathaniel A. Hemstad ◽

Eric C. Merten ◽

Raymond M. Newman

Keyword(s):

Repeated Measures ◽

Riparian Forest ◽

Canopy Cover ◽

Stream Habitat ◽

North Central ◽

Fine Sediments ◽

Repeated Measures Analysis ◽

Stream System ◽

Tree Length ◽

Wide Scale

The response of fish communities and stream habitat to four riparian harvest treatments was studied in north-central Minnesota to determine if riparian harvest with two different harvest systems degrades stream systems. Treatments included control (no harvest), riparian control, cut-to-length riparian thin, and tree length riparian thin. Fish and habitat data were collected from 50 m reaches above, within, and downstream of each treatment 1 year preharvest (1997) and 3 years postharvest (1998–2000). Repeated measures analysis revealed few effects due to treatment; however, there was a 6%–10% significant reduction in canopy cover. Percent fine sediments increased significantly (15%) system-wide following forest harvest and persisted through 2000. This increase in fine sediments was correlated with a decrease in fish biotic integrity (r = –0.31). Habitat and fish variables were influenced more by year-to-year variation than by harvest treatment, suggesting that factors operating at a broader basin-wide scale may influence fish and habitat or mask any site-level harvest effects in this low-gradient stream system. Residual riparian basal areas ≥12.3m2/ha along reaches ≤200 m in length may be adequate to protect fish and habitat in these low-gradient streams, but basin-wide effects of harvest deserve more scrutiny.

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Investigation of Feller-Buncher Performance Using Weibull Distribution

Forests ◽

10.3390/f12030284 ◽

2021 ◽

Vol 12 (3) ◽

pp. 284

Author(s):

Ebru Bilici

Keyword(s):

Weibull Distribution ◽

Shape Parameter ◽

B Value ◽

Productivity Analysis ◽

Volume Data ◽

Estimation Model ◽

Distribution Method ◽

Timber Volume ◽

C Value ◽

The Right

With the advancement of technology in forestry, the utilization of advanced machines in forest operations has been increasing in the last decades. Due to their high operating costs, it is crucial to select the right machinery, which is mostly done by using productivity analysis. In this study, a productivity estimation model was developed in order to determine the timber volume cut per unit time for a feller-buncher. The Weibull distribution method was used to develop the productivity model. In the study, the model of the theoretical (estimated) volume distributions obtained with the Weibull probability density function was generated. It was found that the c value was 1.96 and the b value was 0.58 (i.e., b is the scale parameter, and c is the shape parameter). The model indicated that the frequency of the volume data had moved away from 0 as the shape parameter of the Weibull distribution increased. Thus, it was revealed that the shape parameter gives preliminary information about the distribution of the volume frequency. The consistency of the measured timber volume with the estimated timber volume strongly indicated that this approach can be effectively used by decision makers as a key tool to predict the productivity of a feller-buncher used in harvesting operations.

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Dual Efficiency and Productivity Analysis of Renewable Energy Alternatives of OECD Countries

Sustainability ◽

10.3390/su13137401 ◽

2021 ◽

Vol 13 (13) ◽

pp. 7401

Author(s):

Sedef E. Kara ◽

Mustapha D. Ibrahim ◽

Sahand Daneshvar

Keyword(s):

Renewable Energy ◽

Solar Energy ◽

Wind Energy ◽

Oecd Countries ◽

Malmquist Productivity Index ◽

Productivity Index ◽

Scale Efficiency ◽

Productivity Analysis ◽

Average Efficiency ◽

Efficiency And Productivity

This paper examines the dual efficiency of bioenergy, renewable hydro energy, solar energy, wind energy, and geothermal energy for selected OECD countries through an integrated model with energy, economic, environmental, and social dimensions. Two questions are explored: Which renewable energy alternative is more dual efficient and productive? Which renewable energy alternative is best for a particular country? Data envelopment analysis (DEA) is used for the efficiency evaluation, and the global Malmquist productivity index is applied for productivity analysis. Results indicate bioenergy as the most efficient renewable energy alternative with a 20% increase in average efficiency in 2016 compared to 2012. Renewable hydro energy, wind energy, and solar energy show a 17.5%, 16%, and 11% increase, respectively. The average efficiency growth across all renewable energy alternatives signifies major advancement. Country performance in renewable energy is non-monolithic; therefore, they should customize their renewable energy portfolio accordingly to their strengths to enhance renewable energy efficiency. Renewable hydro appears to have the most positive productivity change in 2016 compared to 2012, while solar energy regressed in productivity due to its scale inefficiency. All renewable energy alternatives have relatively equal average pure efficiency change. The positive trend in efficiency and productivity provides an incentive for policy makers to pursue further development of renewable energy technologies with a focus on improving scale efficiency.

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Deploying cobots in collaborative systems: major considerations and productivity analysis

International Journal of Production Research ◽

10.1080/00207543.2020.1870758 ◽

2021 ◽

pp. 1-17

Author(s):

Yuval Cohen ◽

Shraga Shoval ◽

Maurizio Faccio ◽

Riccardo Minto

Keyword(s):

Collaborative Systems ◽

Productivity Analysis

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